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Thousands of chemicals from daily use are being discharged from civilization into the water cycle via different pathways. Ingredients of personal care products, detergents, pharmaceuticals, pesticides, and industrial chemicals thus find their way into the aquatic ecosystems and may cause adverse impacts on the ecology. Pharmaceuticals for instance, represent a central group of anthropogenic chemicals, because of their designed potency to interfere with physiological functions in organisms. Ecotoxicological effects from pharmaceutical burden have been verified in the past. Therapeutic groups with pronounced endocrine disrupting potentials such as steroid hormones gain increasing focus in environmental research as it was reported that they cause endocrine disruption in aquatic organisms even when exposed to environmentally relevant concentrations. This thesis considers the comprehensive investigation of the occurrence of corticosteroids and progestogens in wastewater treatment plant (WWTP) effluents and surface waters as well as the elucidation of the fate and biodegradability of these steroid families during activated sludge treatment. For the first goal of the thesis, a robust and highly sensitive analytical method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed in order to simultaneously determine the occurrence of around 60 mineralocorticoids, glucocorticoids and progestogens in the aquatic environment. A special focus was set to the compound selection due to the diversity of marketed synthetic steroids. Some analytical challenges have been approved by individual approaches regarding sensitivity enhancement and compound stabilities. These results may be important for further research in environmental analysis of steroid hormones. Reliable and low quantification limits are the perquisite for the determination of corticosteroids and progestogens at relevant concentrations due to low consumption volumes and simultaneously low effect-based trigger values. Achieved quantification limits for all target analytes ranged between 0.02 ng/L and 0.5 ng/L in surface water and 0.05 ng/L to 5 ng/L in WWTP effluents. This sensitivity enabled the detection of three mineralocorticoids, 23 glucocorticoids and 10 progestogens within the sampling campaign around Germany. Many of them were detected for the first time in the environment, particularly in Germany and the EU. To the best of our knowledge, this in-depth steroid screening provided a good overview of single steroid burden and allowed for the identification of predominantly steroids of each steroid
type analyzed for the first time. The frequent detection of highly potent synthetic steroids (e.g. triamcinolone acetonide, clobetasol propionate, betamethasone valerate, dienogest, cyproterone acetate) highlighted insufficient removal during conventional Summary wastewater treatment and indicated the need for regulation to control their emission since the steroid concentrations were found to be above the reported effect-based trigger values for biota. Overall, the study revealed reliable environmental data of poorly or even not analyzed steroids. The results complement the existing knowledge in this field but also providednew information which can beused particularly for compound prioritization in ecotoxicological research and environmental analysis. Based on the data obtained from the monitoring campaign, incubation experiments were conducted to enable the comparison of the biodegradability and transformation processes in activated sludge treatment for structure-related steroids under aerobic and standardized experimental conditions. The compounds were accurately selected to cover manifold structural moieties of commonly used glucocorticoids, including non-halogenated and halogenated steroids, their mono- and diesters, and several acetonide-type steroids. This approach allowed for a structure-based interpretation of the results. The obtained biodegradation rate constants suggested large variations in the biodegradability (half-lifes ranged from < 0.5 h to > 14 d). An increasing stability was identified in the order from non-halogenated steroids (e.g. hydrocortisone), over 9α-halogenated steroids (e.g. betamethasone), to C17-monoesters (e.g. betamethasone 17-valerate, clobetasol propionate), and finally to acetonides (e.g. triamcinolone acetonide), thus suggesting a strong relationship of the biodegradability with the glucocorticoid structure. Some explanations for this behavior have been received by identifying the transformation products (TPs) and elucidating individual transformation pathways. The results revealed the identification of the likelihood of transformation reactions depending on the chemical steroid structure for the first time. Among the identified TPs, the carboxylates (e.g. TPs of fluticasone propionate, triamcinolone acetonide) have been shown persistency in the subsequent incubation experiments. The newly identified TPs furthermore were frequently detected in the effluents of full-scale wastewater treatment plants. These findings emphasized i) the transferability of the lab-scale degradation experiments to real world and that ii) insufficient removals may cause adverse effects in the aquatic environment due to the ability of the precursor steroids and TPs to interact with the endocrine system in biota. For the last goal, the conceptual study for glucocorticoids was applied to progestogens.
Here, two sub-types of the steroid family frequently used for hormonal contraception were selected (17α-hydroxyprogesterone and 19-norstestosterone type). The progestogens showed a fast and complete degradation within six hours, and thus empathizes pronounced biodegradability. However, cyproterone acetate and dienogest Summary have been found to be more recalcitrant in activated sludge treatment. This was consistent with their ubiquitously occurrence during the previous monitoring campaign. The elucidation of TPs again revealed some crucial information regarding the observed behavior and highlighted furthermore the formation of hazardous TPs. It was shown that 19-nortestosterone type steroids are able to undergo aromatization at ring A in contact with activated sludge, leading to the formation of estrogen-like TPs with a phenolic moiety at ring A. In the case of norethisterone the formation of 17α-ethinylestradiol was confirmed, which is a well-known potent synthetic estrogen with elevated ecotoxicological potency. Thus, the results indicated for the very first time an unknown source of estrogenic compounds, particularly for 17α-ethinylestradiol. In conclusion, some steroids were found to be very stable in activated sludge treatment, others degrade well, and others which do degrade but predominantly to active TPs depending on their chemical structure. Fluorinated acetal steroids such as triamcinolone acetonide and fluocinolone acetonide are poorly biodegradable, which is reflected in high concentrations detected ubiquitously in WWTP effluents. Endogenous steroids and their most related synthetic once such as hydrocortisone, prednisolone or 17α-hydroxyprogesterone are readily biodegradable. Regardless their high influent concentrations, they are almost completely removed in conventional WWTPs. Steroids between this range have been found to form elevated quantities of TPs which are partially still active, which particularly the case for betamethasone, fluticasone propionate, cyproterone acetate or dienogest. The thesis illustrates the need for an extensive evaluation of the environmental risks and carried out that corticosteroids and progestogens merit more attention in environmental regulatory and research than it is currently the case
Der Wettbewerb um die besten Technologien zur Realisierung des autonomen Fahrens ist weltweit in vollem Gange.
Trotz großer Anstrengungen ist jedoch die autonome Navigation in strukturierter und vor allem unstrukturierter Umgebung bisher nicht gelöst.
Ein entscheidender Baustein in diesem Themenkomplex ist die Umgebungswahrnehmung und Analyse durch passende Sensorik und entsprechende Sensordatenauswertung.
Insbesondere bildgebende Verfahren im Bereich des für den Menschen sichtbaren Spektrums finden sowohl in der Praxis als auch in der Forschung breite Anwendung.
Dadurch wird jedoch nur ein Bruchteil des elektromagnetischen Spektrums genutzt und folglich ein großer Teil der verfügbaren Informationen zur Umgebungswahrnehmung ignoriert.
Um das vorhandene Spektrum besser zu nutzen, werden in anderen Forschungsbereichen schon seit Jahrzehnten \sog spektrale Sensoren eingesetzt, welche das elektromagnetische Spektrum wesentlich feiner und in einem größeren Bereich im Vergleich zu klassischen Farbkameras analysieren. Jedoch können diese Systeme aufgrund technischer Limitationen nur statische Szenen aufnehmen. Neueste Entwicklungen der Sensortechnik ermöglichen nun dank der \sog Snapshot-Mosaik-Filter-Technik die spektrale Abtastung dynamischer Szenen.
In dieser Dissertation wird der Einsatz und die Eignung der Snapshot-Mosaik-Technik zur Umgebungswahrnehmung und Szenenanalyse im Bereich der autonomen Navigation in strukturierten und unstrukturierten Umgebungen untersucht. Dazu wird erforscht, ob die aufgenommen spektralen Daten einen Vorteil gegenüber klassischen RGB- \bzw Grauwertdaten hinsichtlich der semantischen Szenenanalyse und Klassifikation bieten.
Zunächst wird eine geeignete Vorverarbeitung entwickelt, welche aus den Rohdaten der Sensorik spektrale Werte berechnet. Anschließend wird der Aufbau von neuartigen Datensätzen mit spektralen Daten erläutert. Diese Datensätze dienen als Basis zur Evaluation von verschiedenen Klassifikatoren aus dem Bereich des klassischen maschinellen Lernens.
Darauf aufbauend werden Methoden und Architekturen aus dem Bereich des Deep-Learnings vorgestellt. Anhand ausgewählter Architekturen wird untersucht, ob diese auch mit spektralen Daten trainiert werden können. Weiterhin wird die Verwendung von Deep-Learning-Methoden zur Datenkompression thematisiert. In einem nächsten Schritt werden die komprimierten Daten genutzt, um damit Netzarchitekturen zu trainieren, welche bisher nur mit RGB-Daten kompatibel sind. Abschließend wird analysiert, ob die hochdimensionalen spektralen Daten bei der Szenenanalyse Vorteile gegenüber RGB-Daten bieten
Scientific and public interest in epidemiology and mathematical modelling of disease spread has increased significantly due to the current COVID-19 pandemic. Political action is influenced by forecasts and evaluations of such models and the whole society is affected by the corresponding countermeasures for containment. But how are these models structured?
Which methods can be used to apply them to the respective regions, based on real data sets? These questions are certainly not new. Mathematical modelling in epidemiology using differential equations has been researched for quite some time now and can be carried out mainly by means of numerical computer simulations. These models are constantly being refinded and adapted to corresponding diseases. However, it should be noted that the more complex a model is, the more unknown parameters are included. A meaningful data adaptation thus becomes very diffcult. The goal of this thesis is to design applicable models using the examples of COVID-19 and dengue, to adapt them adequately to real data sets and thus to perform numerical simulations. For this purpose, first the mathematical foundations are presented and a theoretical outline of ordinary differential equations and optimization is provided. The parameter estimations shall be performed by means of adjoint functions. This procedure represents a combination of static and dynamical optimization. The objective function corresponds to a least squares method with L2 norm which depends on the searched parameters. This objective function is coupled to constraints in the form of ordinary differential equations and numerically minimized, using Pontryagin's maximum (minimum) principle and optimal control theory. In the case of dengue, due to the transmission path via mosquitoes, a model reduction of an SIRUV model to an SIR model with time-dependent transmission rate is performed by means of time-scale separation. The SIRUV model includes uninfected (U) and infected (V ) mosquito compartments in addition to the susceptible (S), infected (I) and recovered (R) human compartments, known from the SIR model. The unknwon parameters of the reduced SIR model are estimated using data sets from Colombo (Sri Lanka) and Jakarta (Indonesia). Based on this parameter estimation the predictive power of the model is checked and evaluated. In the case of Jakarta, the model is additionally provided with a mobility component between the individual city districts, based on commuter data. The transmission rates of the SIR models are also dependent on meteorological data as correlations between these and dengue outbreaks have been demonstrated in previous data analyses. For the modelling of COVID-19 we use several SEIRD models which in comparison to the SIR model also take into account the latency period and the number of deaths via exposed (E) and deaths (D) compartments. Based on these models a parameter estimation with adjoint functions is performed for the location Germany. This is possible because since the beginning of the pandemic, the cumulative number of infected persons and deaths
are published daily by Johns Hopkins University and the Robert-Koch-Institute. Here, a SEIRD model with a time delay regarding the deaths proves to be particularly suitable. In the next step, this model is used to compare the parameter estimation via adjoint functions with a Metropolis algorithm. Analytical effort, accuracy and calculation speed are taken into account. In all data fittings, one parameter each is determined to assess the estimated number of unreported cases.
Mathematical models of species dispersal and the resilience of metapopulations against habitat loss
(2021)
Habitat loss and fragmentation due to climate and land-use change are among the biggest threats to biodiversity, as the survival of species relies on suitable habitat area and the possibility to disperse between different patches of habitat. To predict and mitigate the effects of habitat loss, a better understanding of species dispersal is needed. Graph theory provides powerful tools to model metapopulations in changing landscapes with the help of habitat networks, where nodes represent habitat patches and links indicate the possible dispersal pathways between patches.
This thesis adapts tools from graph theory and optimisation to study species dispersal on habitat networks as well as the structure of habitat networks and the effects of habitat loss. In chapter 1, I will give an introduction to the thesis and the different topics presented in this thesis. Chapter 2 will then give a brief summary of tools used in the thesis.
In chapter 3, I present our model on possible range shifts for a generic species. Based on a graph-based dispersal model for a generic aquatic invertebrate with a terrestrial life stage, we developed an optimisation model that models dispersal directed to predefined habitat patches and yields a minimum time until these patches are colonised with respect to the given landscape structure and species dispersal capabilities. We created a time-expanded network based on the original habitat network and solved a mixed integer program to obtain the minimum colonisation time. The results provide maximum possible range shifts, and can be used to estimate how fast newly formed habitat patches can be colonised. Although being specific for this simulation model, the general idea of deriving a surrogate can in principle be adapted to other simulation models.
Next, in chapter 4, I present our model to evaluate the robustness of metapopulations. Based on a variety of habitat networks and different generic species characterised by their dispersal traits and habitat demands, we modeled the permanent loss of habitat patches and subsequent metapopulation dynamics. The results show that species with short dispersal ranges and high local-extinction risks are particularly vulnerable to the loss of habitat across all types of networks. On this basis, we then investigated how well different graph-theoretic metrics of habitat networks can serve as indicators of metapopulation robustness against habitat loss. We identified the clustering coefficient of a network as the only good proxy for metapopulation robustness across all types of species, networks, and habitat loss scenarios.
Finally, in chapter 5, I utilise the results obtained in chapter 4 to identify the areas in a network that should be improved in terms of restoration to maximise the metapopulation robustness under limited resources. More specifically, we exploit our findings that a network’s clustering coefficient is a good indicator for metapopulation robustness and develop two heuristics, a Greedy algorithm and a deducted Lazy Greedy algorithm, that aim at maximising the clustering coefficient of a network. Both algorithms can be applied to any network and are not specific to habitat networks only.
In chapter 6, I will summarize the main findings of this thesis, discuss their limitations and give an outlook of future research topics.
Overall this thesis develops frameworks to study the behaviour of habitat networks and introduces mathematical tools to ecology and thus narrows the gap between mathematics and ecology. While all models in this thesis were developed with a focus on aquatic invertebrates, they can easily be adapted to other metapopulations.
Previous research concerned with early science education revealed that guided play can support young children’s knowledge acquisition. However, the questions whether guided play maintains other important prerequisites such as children’s science self-concept and how guided play should be implemented remain unanswered. The present dissertation encompasses three research articles that investigated 5- to 6-year-old children’s science knowledge, science theories, and science self-concept in the stability domain and their relation to interindividual prerequisites. Moreover, the articles examined whether children’s science knowledge, science theories, and science self-concept can be supported by different play forms, i.e., guided play with material and verbal scaffolds, guided play with material scaffolds, and free play. The general introduction of the present dissertation first highlights children’s cognitive development, their science self-concept, and interindividual prerequisites, i.e., fluid and crystallised intelligence, mental rotation ability, and interest in block play. These prerequisites are applied to possible ways of supporting children during play. The first article focused on the measurement of 5-to-6-year-old children’s stability knowledge and its relation to interindividual prerequisites. Results suggested that children’s stability knowledge could be measured reliably and validly, and was related to their fluid and crystallised intelligence. The second article was concerned with the development of children’s intuitive stability theories over three points of measurement and the effects of guided and free play, children’s prior theories as well as their intelligence on these intuitive theories. Results implied that guided play with material and verbal scaffolds supported children’s stability theories more than the other two play forms, i.e., guided play with material scaffolds and free play. Moreover, consistency of children’s prior theories, their fluid and crystallised intelligence were related to children’s theory adaptation after the intervention. The third article focused on the effect of the playful interventions on children’s stability knowledge and science self-concept over three points of measurement. Furthermore, the reciprocal effects between knowledge acquisition and science self-concept were investigated. Results implied that guided play supported knowledge acquisition and maintained children’s science self-concept. Free play did not support children’s stability knowledge and decreased children’s science self-concept. No evidence for reciprocal effects between children’s stability knowledge and their science self-concept was found. Last, in a general discussion, the findings of the three articles are combined and reflected amidst children’s cognitive development. Summarising, the present dissertation shows that children’s science knowledge, science theories, and science self-concept can be supported through guided play that considers children’s cognitive development.
Ray tracing acceleration through dedicated data structures has long been an important topic in computer graphics. In general, two different approaches are proposed: spatial and directional acceleration structures. The thesis at hand presents an innovative combined approach of these two areas, which enables a further acceleration of the tracing process of rays. State-of-the-art spatial data structures are used as base structures and enhanced by precomputed directional visibility information based on a sophisticated abstraction concept of shafts within an original structure, the Line Space.
In the course of the work, novel approaches for the precomputed visibility information are proposed: a binary value that indicates whether a shaft is empty or non-empty as well as a single candidate approximating the actual surface as a representative candidate. It is shown how the binary value is used in a simple but effective empty space skipping technique, which allows a performance gain in ray tracing of up to 40% compared to the pure base data structure, regardless of the spatial structure that is actually used. In addition, it is shown that this binary visibility information provides a fast technique for calculating soft shadows and ambient occlusion based on blocker approximations. Although the results contain a certain inaccuracy error, which is also presented and discussed, it is shown that a further tracing acceleration of up to 300% compared to the base structure is achieved. As an extension of this approach, the representative candidate precomputation is demonstrated, which is used to accelerate the indirect lighting computation, resulting in a significant performance gain at the expense of image errors. Finally, techniques based on two-stage structures and a usage heuristic are proposed and evaluated. These reduce memory consumption and approximation errors while maintaining the performance gain and also enabling further possibilities with object instancing and rigid transformations.
All performance and memory values as well as the approximation errors are measured, presented and discussed. Overall, the Line Space is shown to result in a considerate improvement in ray tracing performance at the cost of higher memory consumption and possible approximation errors. The presented findings thus demonstrate the capability of the combined approach and enable further possibilities for future work.
Since the Bologna reform a continuous improvement of the lessons’ quality at school, which is often connected with the professionalization of the future teachers and the teaching post education, is aimed by Alliance and federal states. The quality of the lessons is connected with the professionalization of the future teacher and the teaching post education. In most studies about quality improvement the consideration occurs predominantly from the university view and it is seldom related on the subject Sport. The quality study is established on these two points and leads to the main question: Are there any differences in the teachers‘ and learners‘ perceptions of the professionalization of sport teachers in the certain education phases in Rheinland-Pfalz?
With the help of 101 guide interviews and the evaluation according to the Grounded Theory this source question can be answered straight. There were interviewed teachers of the universities, of the state study seminars and the school, as well as learners, to that refer trainees and students. During the study the „missing school relation” crystallizes consistent in all personal groups as key element (core category) in the first and second education phase. The interviewed, which belong to different school forms, give relevant concrete, specific for sport and partially subject covering optimization proposals. As a result a main focus forms untimely relations to the school everyday life and at the same time collect teaching experiences with learning groups at school to get to know their different motor abilities and skills. The improvement approaches concern the university phase and the training period in the study seminars and schools, and the involved consider for necessary a more intensive interlinking of the individual institutions. A mutual, continuous cooperation for the professionalization in the sportsman's education and therefore the optimization of the sports teacher training is very important for all involved.
The sediments of surface waters are temporary or final depository of many chemical compounds, including trace metals and metalloids (metal(loid)s) from natural and anthropogenic sources. Whether they act as a source or sink of metal(loid)s depends strongly on the dynamics of the biogeochemical processes that take place at the sediment-water interface (SWI). Important information on biogeochemical processes as well as on the exposure, the fate and the transport of pollutants at the SWI can be obtained by determining chemical concentration profiles in the sediment pore water. A major challenge is to conduct experiments with a spatial resolution, which allows to adequately record existing gradients and to log all the parameters needed, to describe and better understand the complex processes at the SWIs. At the same time, it is from major importance to prevent the formation of any artifacts during sampling, which may occur due to the labile nature of the SWIs and the very steep biogeochemical gradients.
In this context, in the first part of this work, a system was developed and tested that enables the automated, minimal invasive sampling of sediment pore water of undisturbed or manipulated sediments while simultaneously recording parameters such as redox potential, oxygen content and pH value. In an incubation experiment the impact of acidification and mechanical disturbance (re-suspension) on the mobility of 13 metal(loid)s was investigated using a triple quadrupole inductively coupled plasma-mass spectrometry (ICP-QQQ-MS) multi-element approach. Most metals were released as consequence of sulfide weathering whereas mechanical disturbance had a major impact on the mobility of the oxide forming elements As, Mo, Sb, U and V. Additionally, options were demonstrated to address with the system the size fractionation of metal(loid)s in pore water samples and the speciation of As(III/V) and Sb(III/V).
In the second part, the focus, with a similar experimental design, was placed on the processes leading to the release of metal(loid)s. For this purpose, two incubation experiments with different oxygen supply were conducted in parallel. For the first time the nonmetals carbon, phosphorus and sulfur were analyzed simultaneous to 13 metal(loid)s in sediment pore water by ICP-QQQ-MS. Throughout the experiment metal(loid) size fractionation was monitored. It was confirmed that resuspension promotes the mobility of metalloids such as As, Sb and V, while the release of most metals was largely attributed to pyrite weathering. The colloidal (0.45-16 μm) contribution in terms of mobilization was only relevant for a few elements.
Finally, the sampling system was used as part of a new approach to sediment risk assessment. Undisturbed sediment cores from differently contaminated positions in the Trave estuary were examined, considering 16 metal(loid)s, the non-metals C, P and S and the ions NH4+, PO43- and SO42-. By the first in-depth comparison with in-situ dialysis-based pore water sampling the ability of the suction-based approach to represent field conditions was proven. The pore water studies together with supplementing resuspension experiments in bio-geochemical microcosms and sequential extraction identified the most “pristine” sediment of the study area as posing the greatest risk of metal(loid) release. However, the potentially released amounts per kg of sediment are only a few parts per thousand of the average daily loads of the Trave river.
Enterprise Collaboration Systems (ECS) have become substantial for computer-mediated communication and collaboration among employees in organisations. As ECS combine features from social media and traditional groupware, a growing number of organisations implement ECS to facilitate collaboration among employees. Consequently, ECS form the core of the digital workplace. Thus, the activity logs of ECS are particularly valuable since they provide a unique opportunity for observing and analysing collaboration in the digital workplace.
Evidence from academia and practice demonstrates that there is no standardised approach for the analysis of ECS logs and that practitioners struggle with various barriers. Because current ECS analytics tools only provide basic features, academics and practitioners cannot leverage the full potential of the activity logs. As ECS activity logs are a valuable source for understanding collaboration in the digital workplace, new methods and metrics for their analysis are required. This dissertation develops Social Collaboration Analytics (SCA) as a method for measuring and analysing collaboration activities in ECS. To address the existing limitations in academia and practice and to contribute a method and structures for applying SCA in practice, this dissertation aims to answer two main research questions:
1. What are the current practices for measuring collaboration activities in Enterprise Collaboration Systems?
2. How can Social Collaboration Analytics be implemented in practice?
By answering the research questions, this dissertation seeks to (1) establish a broad thematic understanding of the research field of SCA and (2) to develop SCA as a structured method for analysing ac-tivity logs of ECS. As part of the first research question, this dissertation documents the status quo of SCA in the academic literature and practice. By answering the second research question, this dissertation contributes the SCA framework (SCAF), which guides the practical application of SCA. SCAF is the main contribution of this dissertation. The framework was developed based on findings from an analysis of 86 SCA studies, results from 6 focus groups and results from a survey among 27 ECS user companies. The phases of SCAF were derived from a comparison of established process models for data mining and business intelligence. The eight phases of the framework contain detailed descriptions, working steps, and guiding questions, which provide a step by step guide for the application of SCA in practice. Thus, academics and practitioners can benefit from using the framework.
The constant evaluation of the research outcomes in focus groups ensures both rigour and relevance. This dissertation employs a qualitative-dominant mixed-methods approach. As part of the university-industry collaboration initiative IndustryConnect, this research has access to more than 30 leading ECS user companies. Being built on a key case study and a series of advanced focus groups with representatives of user companies, this dissertation can draw from unique insights from practice as well as rich data with a longitudinal perspective.
The flexible integration of information from distributed and complex information systems poses a major challenge for organisations. The ontology-based information integration concept SoNBO (Social Network of Business Objects) developed and presented in this dissertation addresses these challenges. In an ontology-based concept, the data structure in the source systems (e.g. operational application systems) is described with the help of a schema (= ontology). The ontology and the data from the source systems can be used to create a (virtualised or materialised) knowledge graph, which is used for information access. The schema can be flexibly adapted to the changing needs of a company regarding their information integration. SoNBO differs from existing concepts known from the Semantic Web (OBDA = Ontology-based Data Access, EKG = Enterprise Knowledge Graph) both in the structure of the company-specific ontology (= Social Network of Concepts) as well as in the structure of the user-specific knowledge graph (= Social Network of Business Objects) and makes use of social principles (known from Enterprise Social Software). Following a Design Science Research approach, the SoNBO framework was developed and the findings documented in this dissertation. The framework provides guidance for the introduction of SoNBO in a company and the knowledge gained from the evaluation (in the company KOSMOS Verlag) is used to demonstrate its viability. The results (SoNBO concept and SoNBO framework) are based on the synthesis of the findings from a structured literature review and the investigation of the status quo of ontology-based information integration in practice: For the status quo in practice, the basic idea of SoNBO is demonstrated in an in-depth case study about the engineering office Vössing, which has been using a self-developed SoNBO application for a few years. The status quo in the academic literature is presented in the form of a structured literature analysis on ontology-based information integration approaches. This dissertation adds to theory in the field of ontology-based information integration approaches (e. g. by an evaluated artefact) and provides an evaluated artefact (the SoNBO Framework) for practice.
We are living in a world where environmental crises come to a head. To curb aggravation of these problems, a socio-ecological transformation within society is needed, going along with human behavior change. How to encourage such behavior changes on an individual level is the core issue of this dissertation. It takes a closer look at the role of individuals as consumers resulting in purchase decisions with more or less harmful impact on the environment. By using the example of plastic pollution, it takes up a current environmental problem and focuses on an understudied behavioral response to this problem, namely reduction behavior. More concrete, this dissertation examines which psychological factors can encourage the mitigation of plastic packaging consumption. Plastic packaging accounts for the biggest amount of current plastic production and is associated with products of daily relevance. Despite growing awareness of plastic pollution in society, behavioral responses do not follow accordingly and plastic consumption is still very high. As habits are often a pitfall when implementing more resource-saving behavior, this dissertation further examines if periods of discontinuity can open a ’window of opportunity’ to break old habits and facilitate behavior change. Four manuscripts approach this matter from the gross to the subtle. Starting with a literature review, a summary of 187 studies addresses the topic of plastic pollution and human behavior from a societal-scientific perspective. Based on this, a cross-sectional study (N = 648) examines the deter-minants of plastic-free behavior intentions in the private-sphere and public-sphere by structural equation modeling. Two experimental studies in pre-post design build upon this, by integrating the determinants in intervention studies. In addition, it was evaluated if the intervention presented during Lent (N = 140) or an action month of ‘Plastic Free July’ (N = 366) can create a ‘window of opportunity’ to mitigate plastic packaging consumption. The literature review emphasized the need for research on behavioral solutions to reduce plastic consumption. The empirical results revealed moral and control beliefs to be the main determinants of reduction behavior. Furthermore, the time point of an intervention influenced the likelihood to try out the new behavior. The studies gave first evidence that a ‘window of opportunity’ can facilitate change towards pro-environmental behavior within the application field of plastic consumption. Theoretical and practical implications of creating the right opportunity for individuals to contribute to a socio-ecological transformation are finally discussed.
Graph-based data formats are flexible in representing data. In particular semantic data models, where the schema is part of the data, gained traction and commercial success in recent years. Semantic data models are also the basis for the Semantic Web - a Web of data governed by open standards in which computer programs can freely access the provided data. This thesis is concerned with the correctness of programs that access semantic data. While the flexibility of semantic data models is one of their biggest strengths, it can easily lead to programmers accidentally not accounting for unintuitive edge cases. Often, such exceptions surface during program execution as run-time errors or unintended side-effects. Depending on the exact condition, a program may run for a long time before the error occurs and the program crashes.
This thesis defines type systems that can detect and avoid such run-time errors based on schema languages available for the Semantic Web. In particular, this thesis uses the Web Ontology Language (OWL) and its theoretic underpinnings, i.e., description logics, as well as the Shapes Constraint Language (SHACL) to define type systems that provide type-safe data access to semantic data graphs. Providing a safe type system is an established methodology for proving the absence of run-time errors in programs without requiring execution. Both schema languages are based on possible world semantics but differ in the treatment of incomplete knowledge. While OWL allows for modelling incomplete knowledge through an open-world semantics, SHACL relies on a fixed domain and closed-world semantics. We provide the formal underpinnings for type systems based on each of the two schema languages. In particular, we base our notion of types on sets of values which allows us to specify a subtype relation based on subset semantics. In case of description logics, subsumption is a routine problem. For
the type system based on SHACL, we are able to translate it into a description
logic subsumption problem.
Water scarcity is already an omnipresent problem in many parts of the world, especially in sub-Saharan Africa. The dry years 2018 and 2019 showed that also in Germany water resources are finite. Projections and predictions for the next decades indicate that renewal rates of existing water resources will decline due the growing influence of climate change, but that water extraction rates will increase due to population growth. It is therefore important to find alternative and sustainable methods to make optimal use of the water resources currently available. For this reason, the reuse of treated wastewater for irrigation and recharge purposes has become one focus of scientific research in this field. However, it must be taken into account that wastewater contains so-called micropollutants, i.e., substances of anthropogenic origin. These are, e.g., pharmaceuticals, pesticides and industrial chemicals which enter the wastewater, but also metabolites that are formed in the human body from pharmaceuticals or personal care products. Through the treatment in wastewater treatment plants (WWTPs) as well as through chemical, biological and physical processes in the soil passage during the reuse of water, these micropollutants are transformed to new substances, known as transformation products (TPs), which further broaden the number of contaminants that can be detected within the whole water cycle.
Despite the fact that the presence of human metabolites and environmental TPs in untreated and treated wastewater has been known for a many years, they are rarely included in common routine analysis methods. Therefore, a first goal of this thesis was the development of an analysis method based on liquid chromatography - tandem mass spectrometry (LC-MS/MS) that contains a broad spectrum of frequently detected micropollutants including their known metabolites and TPs. The developed multi-residue analysis method contained a total of 80 precursor micropollutants and 74 metabolites and TPs of different substance classes. The method was validated for the analysis of different water matrices (WWTP influent and effluent, surface water and groundwater from a bank filtration site). The influence of the MS parameters on the quality of the analysis data was studied. Despite the high number of analytes, a sufficient number of datapoints per peak was maintained, ensuring a high sensitivity and precision as well as a good recovery for all matrices. The selection of the analytes proved to be relevant as 95% of the selected micropollutants were detected in at least one sample. Several micropollutants were quantified that were not in the focus of other current multi-residue analysis methods (e.g. oxypurinol). The relevance of including metabolites and TPs was demonstrated by the frequent detection of, e.g., clopidogrel acid and valsartan acid at higher concentrations than their precursors, the latter even being detected in samples of bank filtrate water.
By the integration of metabolites, which are produced in the body by biological processes, and biological and chemical TPs, the multi-residue analysis method is also suitable for elucidating degradation mechanisms in treatment systems for water reuse that, e.g., use a soil passage for further treatment. In the second part of the thesis, samples from two treatment systems based on natural processes were analysed: a pilot-scale above-ground sequential biofiltration system (SBF) and a full-scale soil aquifer treatment (SAT) site. In the SBF system mainly biological degradation was observed, which was clearly demonstrated by the detection of biological TPs after the treatment. The efficiency of the degradation was improved by an intermediate aeration, which created oxic conditions in the upper layer of the following soil passage. In the SAT system a combination of biodegradation and sorption processes occurred. By the different behaviour of some biodegradable micropollutants compared to the SBF system, the influence of redox conditions and microbial community was observed. An advantage of the SAT system over the SBF system was found in the sorption capacity of the natural soil. Especially positively charged micropollutants showed attenuation due to ionic interactions with negatively charged soil particles. Based on the physicochemical properties at ambient pH, the degree of removal in the investigated systems and the occurrence in the source water, a selection of process-based indicator substances was proposed.
Within the first two parts of this thesis a micropollutant was frequently detected at elevated concentrations in WWTPs effluents, which was not previously in the focus of environmental research: the antidiabetic drug sitagliptin (STG). STG showed low degradability in biological systems and thus it was investigated to what extend chemical treatment by ozonation can ensure attenuation of it. STG contains an aliphatic primary amine as the principal point of attack for the ozone molecule. There is only limited information about the behaviour of this functional group during ozonation and thus, STG served as an example for other micropollutants containing aliphatic primary amines. A pH-dependent degradation kinetic was observed due to the protonation of the primary amine at lower pH values. At pH values in the range 6 - 8, which is typical for the environment and in WWTPs, STG showed degradation kinetics in the range of 103 M-1s-1 and thus belongs to the group of readily degradable substances. However, complete degradation can only be expected at significantly higher pH values (> 9). The transformation of the primary amine moiety into a nitro group was observed as the major degradation mechanism for STG during ozonation. Other mechanisms involved the formation of a diketone, bond breakages and the formation of trifluoroacetic acid (TFA). Investigations at a pilot-scale ozonation plant using the effluent of a biological degradation of a municipal WWTP as source water confirmed the results of the laboratory studies: STG could not be removed completely even at high ozone doses and the nitro compound was formed as the main TP and remained stable during further ozonation and subsequent biological treatment. It can therefore be assumed that under realistic conditions both a residual concentration of STG and the formed main TP as well as other stable TPs such as TFA can be detected in the effluents of a WWTP consisting of conventional biological treatment followed by ozonation and subsequent biological polishing steps.
Identifizierung und Quantifizierung von Mikroplastik mittels quantitativer ¹H-NMR Spektroskopie
(2021)
Plastic, and so microplastics (MP), are globally present and represent an increasingly significant problem for the environment. In order to understand the distribution and impact of MP it is important to identify and quantify MP over a wide range of sizes and to ensure comparability of studies. However, comparability of studies is made difficult or even impossible by different MP concentration data. There still is a great need for research in the field of size-independent, quantitative analysis of MP in environmental samples, especially with regard to mass-based MP concentration information. Therefore, this thesis aims to utilize quantitative ¹H-NMR spectroscopy (qNMR) as an alternative method in MP analysis. The qNMR method is a size-independent, mass-based method which can be used as an alternative for MP analysis and has potential for routine analysis. The proof-of-concept was demonstrated for LDPE, PET and PS particles (Chapter 2). Additionally, PVC, PA, and ABS particles were tested to cover the most important polymer types for MP-analysis (Chapter 3). Moreover, using PET, PVC and PS as examples it was examined whether the qNMR method can also be transferred to the more cost-effective NoD method (Chapter 4). Results of method validation of both methods (1D and NoD) show that quantification using the qNMR method is not only possible in principle, but also shows high accuracy (88.0-110 %) and detection limits (1 – 84 µg) that lie within the environmentally relevant range. Furthermore, it was examined whether not only high-field instruments are suitable for MP analysis, but also benchtop devices (low-field instruments), which are much more cost-effective in purchase and maintenance. Increasing measurement times for PET and PS to 30 min and for PVC to 140 min, the lower measuring frequency especially concerning resolving capacity could be compensated (Chapter 4). To address the question of potential matrix effects of environmental samples, matrix effects and recovery rates of sample preparation procedures, which have been developed specifically for the application of the qNMR method were investigated using PET fibers as an example (Chapter 5). It could be shown that environmental matrices do not interfere with the quantitative analysis of MP using qNMR methods. Specific sample preparation methods developed for qNMR analysis can be used with recovery rates > 80 % for different environmental matrices (Chapter 5). Finally, first orienting investigations for the simultaneous determination of several polymer types in one sample are reported (Chapter 6).
There has been little research on out-of-school places of learning and their effec-tiveness in the context of ESD education measures. With the help of a multi-stage analysis, this study identifies out-of-school places of learning with reference to the ESD education concept in the Rhineland-Palatinate study area. To this end, qualita-tive literature analyses were first used to generate ESD criteria, which were opera-tionalised as a methodological instrument in the form of an ESD checklist for out-of-school places of learning. The data obtained in this way provide the basis for the creation of a geographically oriented learning location database with ESD refer-ence. A cartographic visualisation of the data results in a spatial distribution pattern: Thus, there are districts and cities that are well supplied with ESD learning loca-tions, but also real ESD learning location deserts where there is a need to catch up. Furthermore, there is an accumulation of ESD learning sites in areas close to for-ests.
A guideline-based explorative interview with two ESD experts provides additional insights into the question of how ESD has been implemented in the federal state of Rhineland-Palatinate, the extent to which there is a need for optimisation, and which continuing measures are being taken for ESD outside schools within the framework of Agenda 2030.
In addition, a quantitative questionnaire study was carried out with 1358 pupils at 30 out-of-school places of learning after participation in an educational measure, in which environmental awareness, attitudes towards environmental behaviour and local learning were also considered. By including non-ESD learning locations, a comparative study on the effectiveness of ESD learning locations became possible. The statistical data evaluation leads to a variety of interesting results. Contra-intuitively, for instance, the type of learning location (ESD or non-ESD learning lo-cation) is not a significant predictor for the environmental awareness and environ-mental behaviour of the surveyed students, whereas communication structures within educational measures at extracurricular learning locations, the multimediality and action orientation and the duration of educational measures have a significant influence.
Keywords: extracurricular learning locations, education for sustainable develop-ment (ESD), ESD criteria, learning location landscape Rhineland-Palatinate, ESD learning locations, environmental awareness, environmental behaviour.
Successful export sectors in manufacturing and agribusiness are important drivers of structural transformation in Sub-Sahara African countries. Backed by industrial policies and active state involvement, a small number of successful productive export sectors has emerged in Sub-Saharan Africa. This thesis asks the question: How do politics shape the promotion of export-driven industrialisation and firm-level upgrading in Sub-Saharan Africa? It exemplifies this question with an in-depth, qualitative study of the cashew processing industry in Mozambique in the period from 1991 until 2019. Mozambique used to be one of the world’s largest producers and processors of cashew nuts in the 1960s and 1970s. At the end of the 20th century, the cashew processing industry broke down completely but has re-emerged as one of the country’s few successful agro-processing exports.
The thesis draws on theoretical approaches from the fields of political science, notably the political settlements framework, global value chain analysis and the research on technological capabilities to explore why the Mozambican Government supported the cashew processing industry and how Mozambican cashew processors acquired the technological capabilities needed to access the global cashew value chain and to upgrade. It makes an important theoretical contribution by linking the political settlements framework and the literature on upgrading in global value chains to study how politics shaped productive sector promotion and upgrading in the Mozambican cashew processing industry. The findings of the thesis are based on extensive primary data, including 58 expert interviews and 10 firm surveys, that was collected in Mozambique in 2018 as well as a broad base of secondary literature.
The thesis argues that the Mozambican Government supported the cashew processing industry because it became important for the Government’s political survival. Promoting the cashew sector formed part of an electoral strategy for the ruling FRELIMO coalition and a means to keep FRELIMO factions united by offering economic opportunities to key constituencies. In 1999, it adopted a protectionist cashew law that created strong incentives for cashew processing in Mozambique. This not only facilitated the re-emergence of the cashew processing industry after its breakdown. The law and the active involvement of the National Cashew Institute (INCAJU) also affected the governance of the local cashew value chain, the creation of backward linkages, and the upgrading paths of cashew processors. The findings of the thesis suggest that the cashew law reduced the pressure on the cashew processing industry to upgrade. The law further created opportunities for formal and informal rent creation for members of the political elite and lower level FRELIMO officials that prevented a far-reaching reform of the law. The thesis shows that international buyers do not promote upgrading among Sub-Sahara African firms in global value chains with market-based or modular governance. Moreover, firms that operate in countries where industrial policies are not enforced effectively cannot draw on the support of government institutions to enhance their capabilities and to upgrade. Firms therefore mainly depended on costly learning channels at firm level, e.g. learning by doing or hiring skilled labour, and/or on technical assistance from donors to build the technological capabilities needed to access global value chains and to remain competitive.
The findings of the thesis suggest that researchers, governments, development practitioners and consultants need to rethink their understanding of upgrading in GVCs in four ways. First, they need to move away from understanding upgrading in terms of moving towards more complex, higher value-added activities in GVCs (functional upgrading). Instead, it is important to consider the potential of other, more realistic types of upgrading for firms in low-income countries, such reducing risks by diversifying suppliers and buyers or increasing rewards by making production processes more efficient. Second, they need to replace an overly positive view on upgrading that neglects possible side-effects at sector and/or country level. Third, GVC participation on its own does not promote upgrading among local supplier firms in Sub-Saharan Africa. The interests of lead firms and Sub-Sahara African supplier firms may not be aligned or even conflicting. Targeted industrial policies and the creation of institutions that effectively promote capability building among firms therefore become even more important. Finally, upgrading needs to be understood as a process that is not only shaped by interactions between firms, but also by local domestic politics.
The findings of the thesis are highly relevant for scholars from the fields of political science, development studies, and economics. Its practical implications and tools, e.g. a technological capabilities matrix for the cashew industry, are of interest for development practitioners, members of public institutions in Sub-Sahara African countries, local entrepreneurs, and representatives of local business associations that are involved in promoting export sectors and upgrading among local firms.
Water is used in a way as if it were available infinitely. Droughts, increased rainfall or flooding already lead to water shortages and, thus, deprive entire population groups of the basis of their livelihoods. There is a growing fear that conflicts over water will increase, especially in arid climate zones, because life without water - whether for humans, animals or plants - is not possible.
More than 60 % of the African population depend on land and water resources for their livelihoods through pastoralism, fishing and farming. The water levels of rivers and lakes are decreasing. Hence, the rural population which is dependent on land and water move towards water-rich and humid areas. This internal migration increases the pressure on available water resources. Driven by the desire to strengthen the economic development, African governments align their political agendas with the promotion of macro international and national economic projects.
This doctoral thesis examines the complex interrelationships between water shortages, governance, vulnerability, adaptive capacity and violent and non-violent conflicts at Lake Naivasha in Kenya and Lake Wamala in Uganda. In order to satisfy the overall complexity, this doctoral thesis combines various theoretical and empirical aspects in which a variety of methods are applied to different geographical regions, across disciplines, and cultural and political boundaries.
The investigation reveals that Lake Naivasha is more affected by violent conflicts than Lake Wamala. Reasons for this include population growth, historically grown ethnic conflicts, corruption and the preferential treatment of national and international economic actors. The most common conflict response tools are raiding and the blockage of water access. However, deathly encounters, destruction of property and cattle slaughtering are increasingly used to gain access to water and land.
The insufficient implementation of the political system and the governments’ prioritization to foster economic development results, on the one hand, in the commercialization of water resources and increases, on the other hand, non-violent conflict between national and sub-national political actors. While corruption, economic favours and patronage defuse this conflict, resource access becomes more difficult for the local population. Resulting thereof, a final hypothesis is developed which states that the localization of the political conflict aggravates the water situation for the local population and, thereby, favours violent conflicts over water access and water use in water-rich areas.
Within the field of Business Process Management, business rules are commonly used to model company decision logic and govern allowed company behavior. An exemplary business rule in the financial sector could be for example:
”A customer with a mental condition is not creditworthy”. Business rules are
usually created and maintained collaboratively and over time. In this setting,
modelling errors can occur frequently. A challenging problem in this context is
that of inconsistency, i.e., contradictory rules which cannot hold at the same
time. For instance, regarding the exemplary rule above, an inconsistency would
arise if a (second) modeller entered an additional rule: ”A customer with a mental condition is always creditworthy”, as the two rules cannot hold at the same
time. In this thesis, we investigate how to handle such inconsistencies in business
rule bases. In particular, we develop methods and techniques for the detection,
analysis and resolution of inconsistencies in business rule bases
Rivers play an important role in the global water cycle, support biodiversity and ecological integrity. However, river flow and thermal regimes are heavily altered in dammed rivers. These impacts are being exacerbated and become more apparent in rivers fragmented by multiple dams. Recent studies mainly focused on evaluating the cumulative impact of cascade reservoirs on flow or thermal regimes, but the role of upstream reservoirs in shaping the hydrology and hydrodynamics of downstream reservoirs remains poorly understood. To improve the understanding of the hydrodynamics in cascade reservoirs, long-term observational data are used in combination with numerical modeling to investigate the changes in flow and thermal regime in three cascade reservoirs at the upper reach of the Yangtze River. The three studied reservoirs are Xiluodu (XLD), Xiangjiaba (XJB) and Three Gorges Reservoir (TGR). In addition, the effects of single reservoir operation (at seasonal/daily time scale) on hydrodynamics are examined in a large tributary of TGR. The results show that the inflow of TGR has been substantially altered by the two upstream reservoirs with a higher discharge in spring and winter and a reduced peak flow in summer. XJB had no obvious contribution to the variations in inflow of TGR. The seasonal water temperature of TGR was also widely affected by the upstream two reservoirs, i.e., an increase in winter and decrease in spring, associated with a delay in water temperature rise and fall. These effects will probably be intensified in the coming years due to the construction of new reservoirs. The study also underlines the importance of reservoir operation in shaping the hydrodynamics of TGR. The seasonal dynamics of density currents in a tributary bay of TGR are closely related to seasonal reservoir operations. In addition, high-frequency water level fluctuations and flow velocity variations were observed in response to periodic tributary bay oscillations, which are driven by the diurnal discharge variations caused by the operation of TGR. As another consequence of operation of cascade reservoirs, the changes in TGR inflow weakened spring thermal stratification and caused warming in spring, autumn and winter. In response to this change, the intrusions from TGR occurred more frequently as overflow and earlier in spring, which caused a sharp reduction in biomass and frequency of phytoplankton blooms in tributary bays of TGR. This study suggests that high-frequency bay oscillations can potentially be used as an efficient management strategy for controlling algal blooms, which can be included in future multi-objective ecological conservation strategies.
Method development for the quantification of pharmaceuticals in aqueous environmental matrices
(2021)
As a consequence of the world population increase and the resulting water scarcity, water quality is the object of growing attention. In that context, organic anthropogenic molecules — often defined as micropollutants— represent a threat for water resources. Among them, pharmaceuticals are the object of particular concerns due to their permanent discharge, their increasing consumption and their effect-based structures. Pharmaceuticals are mainly introduced in the environment via wastewater treatment plants (WWTPs), along with their metabolites and the on-site formed transformation products (TPs). Once in the aquatic environment, they partition between the different environmental compartments in particular the aqueous phase, suspended particulate matter(SPM) and biota. In the last decades, pharmaceuticals have been widely investigated in the water phase. However, extreme polar pharmaceuticals have rarely been monitored due to the lack of robust analytical methods. Moreover, metabolites and TPs have seldom been included in routine analysis methods although their environmental relevance is proven. Furthermore, pharmaceuticals have been only sporadically investigated in SPM and biota and adequate multi-residue methods are lacking to obtain comprehensive results about their occurrence in these matrices. This thesis endeavors to cover these gaps of knowledge by the development of generic multi-residue methods for pharmaceuticals determination in the water phase, SPM and biota and to evaluate the occurrence and partition of pharmaceuticals into these compartments. For a complete overview, a particular focus was laid on extreme polar pharmaceuticals, pharmaceutical metabolites and TPs. In total, three innovative multi-residue methods were developed, they include analytes covering a broad range of physico-chemical properties. First, a reliable multi-residue method was developed for the analysis of extreme polar pharmaceuticals, metabolites and TPs dissolved in water. The selected analytes covered a significant range of elevated polarity and the method would be easily expendable to further analytes. This versatility could be achieved by the utilization of freeze-drying as sample preparation and zwitterionic hydrophilic interaction liquid chromatography (HILIC) in gradient elution mode. The suitability of HILIC chromatography to simultaneously quantify a large range of micropollutants in aqueous environmental samples was thoroughly studied. Several limitations were pointed out: a very complex and time-consuming method development, a very high sensitivity with regards to modification of the acetonitrile to water ratio in the eluent or the diluent and high positive matrix effects for certain analytes. However, these limitations can be overcome by the utilization of a precise protocol and appropriate labeled internal standards. They are overmatched by the benefits of HILIC which permits the chromatographic separation of extreme polar micropollutants. Investigation of environmental samples showed elevated concentrations of the analytes in the water phase. In particular, gabapentin, metformin, guanylurea and oxypurinol were measured at concentrations in the µg/L range in surface water. Subsequently, a reliable multi-residue method was established for the determination of 57 pharmaceuticals, 47 metabolites and TPs sorbed to SPM down to the low ng/g range. This method was conceived to cover a large range of polarity in particular with the inclusion of extreme polar pharmaceuticals. The extraction procedure was based on pressurized liquid extraction (PLE) followed by a clean-up via solvent exchange and detection via direct injection-reversed-phase LC-MS/MS and freeze-drying HILIC-MS/MS. Pharmaceutical sorption was examined using laboratory experiments. Derived distribution coefficients Kd varied by five orders of magnitude among the analytes and confirmed a high sorption potential for positively charged and nonpolar pharmaceuticals. The occurrence of pharmaceuticals in German rivers SPM was evaluated by the investigation of annual composite SPM samples taken at four sites at the river Rhine and one site at the river Saar between the years 2005 and 2015. It revealed the ubiquitous presence of pharmaceuticals sorbed to SPM in these rivers. In particular, positively charged analytes, even very polar and nonpolar pharmaceuticals showed appreciable concentrations. For many pharmaceuticals, a distinct correlation was observed between the annual quantities consumed in Germany and the concentrations measured in SPM. Studies of composite SPM spatial distribution permitted to get hints about specific industrial discharge by comparing the pollution pattern along the river. For the first time, these results showed the potential of SPM for the monitoring of positively charged and nonpolar pharmaceuticals in surface water. Finally, a reliable and generic multi residue method was developed to investigate 35 pharmaceuticals and 28 metabolites and TPs in fish plasma, fish liver and fish fillet. For this matrix, it was very challenging to develop an adequate clean-up allowing for the sufficient separation of the matrix disturbances from the analytes. In the final method, fish tissue extraction was performed by cell disruption followed by a non-discriminating clean-up based on silica gel solid-phase extraction(SPE) and restrictive access media (RAM) chromatography. Application of the developed method to the measurement of bream and carp tissues from German rivers revealed that even polar micropollutants such as pharmaceuticals are ubiquitously present in fish tissues. In total, 17 analytes were detected for the first time in fish tissues, including 10 metabolites/TPs. The importance of monitoring metabolites and TPs in fish tissues was confirmed with their detection at similar concentrations as their parents. Liver and fillet were shown to be appropriate for the monitoring of pharmaceuticals in fish, whereas plasma is more inconvenient due to very low concentrations and collection difficulties. Elevated concentrations of certain metabolites suggest possible formation of human metabolites in fish. Measured concentrations indicate a low bioaccumulation potential for pharmaceuticals in fish tissues.
Real-time operating systems for mixed-criticality systems
must support different types of software, such as
real-time applications and general purpose applications,
and, at the same time, must provide strong spatial and
temporal isolation between independent software components.
Therefore, state-of-the-art real-time operating systems
focus mainly on predictability and bounded worst-case behavior.
However, general purpose operating systems such as Linux
often feature more efficient---but less deterministic---mechanisms
that significantly improve the average execution time.
This thesis addresses the combination of the two contradicting
requirements and shows thread synchronization mechanisms
with efficient average-case behavior, but without sacrificing
predictability and worst-case behavior.
This thesis explores and evaluates the design space of fast paths
in the implementation of typical blocking synchronization
mechanisms, such as mutexes, condition variables, counting
semaphores, barriers, or message queues. The key technique here
is to avoid unnecessary system calls, as system calls have high
costs compared to other processor operations available in user
space, such as low-level atomic synchronization primitives.
In particular, the thesis explores futexes, the state-of-the-art
design for blocking synchronization mechanisms in Linux
that handles the uncontended case of thread synchronization
by using atomic operations in user space and calls into the
kernel only to suspend and wake up threads. The thesis also
proposes non-preemptive busy-waiting monitors that use an
efficient priority ceiling mechanism to prevent the lock holder
preemption problem without using system calls, and according
low-level kernel primitives to construct efficient wait and
notify operations.
The evaluation shows that the presented approaches
improve the average performance comparable
to state-of-the-art approaches in Linux.
At the same time, a worst-case timing analysis shows
that the approaches only need constant or bounded temporal
overheads at the operating system kernel level.
Exploiting these fast paths is a worthwhile approach
when designing systems that not only have to fulfill
real-time requirements, but also best-effort workloads.
Schizophrenia is a chronic mental health disorder, which changes rapidly the life of the persons and their families, who suffer from it. It causes high biological and psychological vulnerability as well as cognitive, emotional and behavioral disorders. Nowadays, evidence-based pharmacotherapy and psychotherapy are available aiming the rehabilitation and recovery of individuals with schizophrenia. A democratic society is obliged to give these people the opportunity to have an access to those treatments.
The following three published studies present this dissertation thesis and have a common focus on the implementation of evidence-based psychotherapy in individuals with schizophrenia.
The first study evaluates the efficacy of the Integrated Psychological Therapy (IPT) in Greece, one of the most evaluated rehabilitation programs. IPT was compared to
Treatment as Usual (TAU) in a randomized controlled trial (RCT) with 48 individuals with schizophrenia. Significant effects favouring IPT were found in working memory,
in social perception, in negative symptoms, in general psychopathology and in insight. This study supports evidence for the efficacy of IPT in Greece.
The second study evaluates a second hypothesis, when IPT is more and less effective regarding treatment resistant schizophrenia (TRS) and non treatment resistant
schizophrenia (NTRS). It is a part of the first paper. Significant effects favouring NTRS were found for verbal memory, for symptoms, for functioning and quality of
life. Effect sizes showed superiority of NTRS in comparison to TRS. IPTTRS showed on the other side some significant improvements. This study presents the initial findings of a larger study to be conducted internationally for the first time.
The third study is a systematic review, which aims to evaluate the efficacy of Cognitive Behavioral Therapy (CBT), of Meta Cognitive Therapy (MCT), Metacognitive Training (MCTR), Metacognitive Reflection and Insight Therapy
(MERIT), of various Rehabilitation Programs and Recovery Programs in individuals with schizophrenia. 41 RCTs and 12 Case Studies were included. The above interventions are efficacious in the improvement of cognitions, symptoms, functional outcome, insight, self-esteem, comorbid disorders and metacognitive capacity.
The three studies provide insight regarding the importance of evidence-based psychotherapy in persons with schizophrenia leading to recovery and reintegration into
society. Future RCTs with larger samples and long-term follow up, combining evidence-based psychotherapies for individuals with schizophrenia need to be done.
Internationale Bildungsstudien (TIMSS und PISA) offenbarten, dass es deutschen Schülern nur begrenzt gelingt, ihr erworbenes Wissen im Physikunterricht zur Problemlösung in neuen Kontexten zu nutzen. Als Grund nennen die Studien die gering ausgeprägte Kompetenz-erwartung in Bezug zum Fach Physik. Die Folge ist eine geringe Motivation der Lernenden, physikalische Aufgaben zu lösen. Studien zeigen aber auch, dass die Motivation beim Lernen durch den Einsatz digitaler Lernmedien gesteigert werden konnte. Aus diesem Grund wird in dieser Arbeit untersucht, ob das Vertrauen in die eigenen Fähigkeiten durch das Lernen in einer integrierten Lernumgebung gefördert werden kann. Im Rahmen eines Design-Based-Research-Forschungsansatzes (DBR) wurde eine integrierte Lernumgebung „Wärmelehre“ mit digitalen Lernmedien für den Physikunterricht gestaltet, die dann in zwei Schulformen (IGS und Gymnasium) innerhalb einer quasi-experimentellen Feldstudie erprobt wurde. Im 1. Zyklus des DBR wurden die Wirkungen des selbstständigen Lernens mit digitalen/analogen Medien in Einzelarbeit untersucht. Die Ergebnisse der Wissenstests zeigen einen höheren Lernerfolg bei den Lernenden der Experimentalgruppen, der sich aber nicht signifikant von den Lernenden der Kontrollgruppen (analoge Medien) unterscheidet. Die Lernenden konnten sich in der integrierten Lernumgebung mit Unterstützung beider Medienformate selbstständig Fachwissen aneignen und problembasierte Textaufgaben lösen. Die Ergebnisse der Befragungen der Lernenden zeigen, dass sich die Lerngruppen signifikant in ihrem erlebten Grad der Selbststeuerung unterscheiden. Die Lernenden beider Experimentalgruppen bewerten ihren Handlungsspielraum besser als die Lernenden der beiden Kontrollgruppen. Ebenfalls konnte festgestellt werden, dass sich die individuellen Lernvoraussetzungen, der Lernstiltyp, das Kompetenzerleben und die Aspekte der Medien-gestaltung wechselseitig beeinflussen und auf den Lernerfolg wirken. Die Ergebnisse der Lernstilanalyse zeigen, dass sich selbst kleine Lerngruppen heterogen zusammensetzen. Demnach scheint es für einen guten Lernerfolg notwendig zu sein, dass die Lehrenden, die Lernumgebung an die individuellen Lernpräferenzen der Lernenden der Lerngruppe anpassen. Aus den Ergebnissen lässt sich als Konsequenz für den Physikunterricht ableiten, dass Selbstlernphasen mit digitalen Lernmedien regelmäßig in den Unterricht integriert werden sollten, um die Problemlöse- und die Selbststeuerungskompetenz zu fördern. Es ist von Vorteil, wenn die Lehrenden für die Gestaltung einer Lernumgebung, das Vorwissen, die individuellen Lernvoraussetzungen und die Zusammensetzung der Lerngruppe (Lernstiltyp) als Qualitätsdimensionen erfassen. Im Re-Design werden Vorschläge unterbreitet, wie die integrierte Lernumgebung lernstilgerecht weiterentwickelt werden kann. Im 2. Zyklus soll dann erforscht werden, ob sich Unterschiede im Lernerfolg und in den untersuchten Aspekten zeigen, wenn die Lernenden in Einzelarbeit, in Partnerarbeit oder in ihrer Lernstilgruppe selbstgesteuert lernen, um die Lernumgebung zyklisch weiterzuentwickeln.
This thesis examined two specific cases of point and diffuse pollution, pesticides and salinisation, which are two of the most concerning stressors of Germany’s freshwater bodies. The findings of this thesis were organized into three major components, of which the first component presents the contribution of WWTPs to pesticide toxicity (Chapter 2). The second component focuses on the current and future background salt ion concentrations under climate change with the absence of anthropogenic activities (Chapter 3). Finally, the third major component shows the response of invertebrate communities in terms of species turnover to levels of salinity change, considered as a proxy for human-driven salinisation (Chapter 4).
Obwohl Kinder beim Bauen mit Bauklötzen bereits früh Erfahrungen mit Aspekten der Stabilität von Bauwerken, wie z. B. Kräfteverteilung, Standfestigkeit sowie Gleich- und Gegengewicht, sammeln und es verschiedene Studien gibt, die den fächerübergreifenden Lerngehalt von Bauklötzen hervorheben, ist das Verständnis bezüglich der Stabilität von Bauklotzanordnungen bisher kaum erforscht. Daher wurde untersucht, welche Vorstellungen sechs- bis siebenjährige Kinder zur Stabilität von Bauklotzanordnungen zeigen und welche Unterstützungsmaßnahmen eine Vorstellungsveränderung anregen. In Studie 1 und 2 zeigt sich, dass Kinder in der Schuleingangsphase erste Vorstellungen zur Stabilität von Bauklotzanordnungen haben. Über verschiedene Analysen wurden schwierigkeitsbestimmende Merkmale bzw. lösungsrelevante Dimensionen identifiziert. Kinder mit ca. fünf Jahren orientieren sich eher an der geometrischen Mitte und beziehen somit die Abstandsdimension ein, bei Neunjährigen berücksichtigen hingegen knapp über die Hälfte bereits den Massenmittelpunkt. Folglich reicht die „Bauerfahrung“ von Kindern bis zum neunten Lebensjahr nicht aus, um die Fähigkeit, Bauklotzanordnungen bezüglich ihrer Stabilität zu beurteilen, vollständig zu entwickeln. Deshalb wurde in Studie 3 untersucht, inwieweit sich eine Vorstellungsveränderung zur Stabilität von Bauklotzanordnungen mithilfe verschiedener Unterstützungsmaßnahmen innerhalb einer kurzen Lerneinheit anregen lässt. Dabei wurden verschiedene materiale und verbale Unterstützungsmaßnahmen in Form von Fotos und gezielten sprachlichen Instruktionen in einem systematischen Vergleich gegenübergestellt. Die Ergebnisse weisen nach, dass bereits mit einer kurzen Lerneinheit ein Wissenszuwachs bei Siebenjährigen angeregt werden kann, insbesondere wenn sie durch Fotos und gezielte sprachliche Instruktionen unterstützt werden. Die Ergebnisse sind ein erster Schritt für die Entwicklung eines naturwissenschaftlichen Unterrichts zur Stabilität von Bauklotzanordnungen.
Das Hauptziel der vorliegenden Arbeit ist die Absicherung der Qualität eines pharmazeutischen Produktionsprozesses durch die Überprüfung des Volumens mikroskopischer Polymerstäbchen mit einem hochgenauen 3D Messverfahren. Die Polymerstäbchen werden für pharmazeutische Anwendungen hergestellt. Aus Gründen der Qualitätssicherung muss das Istgewicht überprüft werden. Derzeit werden die Polymerstäbchen stichprobenartig mit einer hochpräzisen Waage gewogen. Für die nächste Generation von Polymeren wird angenommen, dass die Produktabmessungen weiter reduziert werden sollen und die Produktionstoleranzen auf 2,5% gesenkt werden. Die daraus resultierenden Genauigkeitsanforderungen übersteigen jedoch die Möglichkeiten der Wiegetechnik. Bei homogenen Materialien ist die Masse proportional zum Volumen. Aus diesem Grund kommt dessen Bestimmung als Alternative in Frage. Dies verschafft Zugang zu optischen Messverfahren und deren Flexibilität und Genauigkeitpotenzial. Für den Entwurf eines auf die Fragestellung angepassten Messkonzeptes sind weiterhin von Bedeutung, dass das Objekt kontaktlos, mit einer Taktzeit von maximal fünf Sekunden vermessen und das Volumen approximiert wird. Die Querschnitte der Polymerstäbchen sind etwa kreisförmig. Aufgrund der Herstellung der Fragmente kann nicht davon ausgegangen werden, dass die Anlageflächen orthogonal zur Symmetrieachse des Objektes sind. Daher muss analysiert werden, wie sich kleine Abweichungen von kreisförmigen Querschnitten sowie die nicht idealen Anlageflächen auswirken. Die maximale Standardabweichung für das Volumen, die nicht überschritten werden sollte, beträgt 2,5%. Dies entspricht einer maximalen Abweichung der Querschnittsfläche um 1106 µm² (Fehlerfortpfanzung). Als Bewertungskriterium wird der Korrelationskoeffzient zwischen den gemessenen Volumina und den Massen bestimmt. Ein ideales Ergebnis wäre 100%. Die Messung zielt auf einen Koeffzienten von 98% ab. Um dies zu erreichen, ist ein präzises Messverfahren für Volumen erforderlich. Basierend auf dem aktuellen Stand der Technik können die vorhandenen optischen Messverfahren nicht verwendet werden. Das Polymerstäbchen wird von einer Kamera im Durchlicht beobachtet. Daher sind der Durchmesser und die Länge sichtbar. Das Objekt wird mittels einer mechanischen Vorrichtung um die Längsachse gedreht. So können Bilder von allen Seiten aufgenommen werden. Der Durchmesser und die Länge werden mit der Bildverarbeitung berechnet. Das neue Konzept vereint die Vorteile der Verfahren: Es ist unempfindlich gegen Farb-/Helligkeitsänderungen und die Bilder können in beliebiger Anzahl aufgenommen werden. Außerdem sind die Erfassung und Auswertung wesentlich schneller. Es wird ein Entwurf und die Umsetzung einer Lösung zur hochpräzisen Volumenmessung von Polymerstäbchen mit optischer Messtechnik und Bildverarbeitung ausgearbeitet. Diese spezielle Prozesslösung in der Prozesslinie (inline) sollte eine 100%ige Qualitätskontrolle während der Produktion garantieren. Die Zykluszeiten des Systems sollte fünf Sekunden pro Polymerstäbchen nicht überschreiten. Die Rahmenbedienungen für den Prozess sind durch die Materialeigenschaften des Objekts, die geringe Objektgröße (Breite = 199 µm, Länge = 935 µm bis 1683 µm) und die undeffinierte Querschnittsform (durch den Trocknungsprozess) vorgegeben. Darüber hinaus sollten die Kosten für den Prozess nicht zu hoch sein. Der Messaufbau sollte klein sein und ohne Sicherheitsvorkehrungen oder Abschirmungen arbeiten. Das entstandene System nimmt die Objekte in verschiedenen Winkelschritten auf, wertet mit Hilfe der Bildverarbeitung die Aufnahmen aus und approximiert das Volumen. Der Korrelationskoffizient zwischen Volumen und Gewicht beträgt für 77 Polymerstäbchen mit einem Gewicht von 37 µg bis 80 µg 99; 87%. Mit Hilfe eines Referenzsystems kann die Genauigkeit der Messung bestimmt werden. Die Standardabweichung sollte maximal 2,5% betragen. Das entstandene System erzielt eine maximale Volumenabweichung von 1,7%. Die Volumenvermessung erfüllt alle Anforderungen und kann somit als Alternative für die Waage verwendet werden.
Perfluorocarboxylic acids (PFCA) are substances of anthropogenic origin and have been used for several decades. These compounds are a new class of environmental pollutants. Their high surface activity, thermal stability, amphipathicity and weak intermolecular interactions lead to persistence and bioaccumulation. Therefore, there is a great need for reliable analytical methods for detecting the presence and determination of concentration in both environmental samples and everyday products. GC-MS is a cost-effective alternative and supplement to established LC-MS/MS methods. The greatest challenge in the method development is the derivatization reaction. Many of the previously published derivatization reactions for PFCA are time consuming and require high reaction temperatures or toxic reagents.
In the present dissertation, two new derivatization reactions for PFCA have been developed and optimized. The first part of the thesis shows the development and optimization of the reaction with triethylsilanol in water. In addition to optimizing the reaction, classical solid-phase extraction was modified to simplify the sample preparation.
In the second part of the work, the reaction products of perfluorooctanoic acid (PFOA) with N,N-dimethylformamide dimethyl acetal (DMF-DMA) and -diethyl acetal (DMF-DEA) were identified. From these measurements, it follows that both DMF-DMA and DMF-DEA in the presence of PFOA form an iminium cation, which leads to salt formation. This PFOA salt react further in the GC injector and a corresponding amine is produced.
In the last part of the thesis, an analytical method based on the DMF-DMA reaction was developed. The matrix effects have been described in detail. The method has been successfully applied for three different types of samples: dental floss, textiles and sewage sludge. The results were verified by LC-MS/MS analysis in an external laboratory. The differences between the PFCA values for a spiked sample measured by GC-MS and LC-MS/MS were less than 10%.
Eine zutreffende Diagnose über den aktuellen Kenntnisstand der jeweiligen Schülerinnen und Schüler ist notwendig, um adäquat in Gruppenarbeitsprozesse intervenieren zu können. Von diesem Zusammenhang wird in der Literatur weit-gehend ausgegangen, jedoch gibt es bisher kaum empirische Studien, die diesen belegen. Die vorliegende Arbeit widmet sich schwerpunktmäßig dem Interventi-onsverhalten von Studierenden. Dabei wird die prozessdiagnostische Fähigkeit „Deuten“ zugrundegelegt, um unterschiedliches Interventionsverhalten auf diese Fähigkeit zurückführen zu können. Sowohl beim Aufbau diagnostischer Fähig-keiten als auch bei der (Weiter-)Entwicklung des eigenen Lehrerhandelns gilt Reflexion als hilfreich. Entsprechend wird auch das Zusammenspiel von Pro-zessdiagnose und Reflexionsverhalten sowie von Interventionsverhalten und Reflexionsverhalten untersucht.
Für die Erhebung der prozessdiagnostischen Fähigkeit „Deuten“ wurden drei Videovignetten erstellt und in das Videodiagnosetool ViviAn eingebunden. Die Videovignetten zeigen jeweils vier Schülerinnen, die sich mit dem Thema „Ter-me“ beschäftigen. Im Rahmen eines Lehr-Lern-Labores wurden über vier Se-mester hinweg alle teilnehmenden Studierenden dazu angehalten, die Videovig-netten zu bearbeiten. Ebenso konzipierten sie jeweils zu dritt eine Laborstation im Mathematik-Labor „Mathe ist mehr“ und erprobten diese mit einer Schul-klasse. Dabei wurden die Interventionen der Studierenden in die Gruppenarbeits-prozesse der Schülerinnen und Schüler videographiert. Anschließend reflektierten die Studierenden in Kleingruppen über die Erprobungen und über die getätigten Interventionen. Die Reflexionsgespräche wurden ebenfalls videographiert.
Es zeigt sich, dass die Studierenden, die sich zum Zeitpunkt der Erhebung im Masterstudium befanden, noch Entwicklungsspielraum in Bezug auf ihre pro-zessdiagnostische Fähigkeit „Deuten“ besitzen. Im Hinblick auf die Interventio-nen waren responsive Interventionen häufiger angemessen als invasive Interven-tionen, wobei responsive Internvetionen auch vergleichsweise häufiger dazu führten, dass mehr Schülerinnen und Schüler nach der Intervention aktiv waren. Studierende mit höherer prozessdiagnostischer Fähigkeit „Deuten“ intervenierten jedoch häufiger invasiv und tätigten dabei trotzdem angemessenere und aktivie-rendere Interventionen als ihre Kommilitoninnen und Kommilitonen. Entspre-chend scheint sich die prozessdiagnostische Fähigkeit „Deuten“ positiv auf die Interventionen der Studierenden auszuwirken und sollte daher bereits im Rah-men des (Lehramts-)Studiums verstärkt geschult werden.
Warum kann ich mir nicht vorstellen, meine Haare wachsen zu lassen, insbesondere meine Körperhaare? Diese Frage und das damit verbundene Unbehagen motivierten mich 2016 zur Entwicklung meines Dissertationsprojektes.
Die Suche nach einer Antwort führt zu einer Studie, die einen feministisch-phänomenologischen Erfahrungsbegriff zentral setzt. Bedeutsam für die Entwicklung eines solchen Begriffs sind die phänomenologischen Beiträge „Zur poststrukturalistischen Kritik an der Erfahrung im Kontext der feministischen Philosophie“ (Stoller 2005) von Silvia Stoller und „Phänomenologie, Poststrukturalismus und feministische Theorie. Zum Begriff der Erfahrung“ (Alcoff 1997) von Linda Martín Alcoff. Darauf aufbauend verfolgt das Dissertationsprojekt zunächst das Anliegen, Erfahrungen sichtbar zu machen, indem sie veranschaulicht und zur Sprache gebracht werden. Auf diese Weise wird es möglich, Erfahrungen hinterfragen zu können, um anschließend Antworten entwickeln zu können. Demnach beruhen mein Unvermögen, Körperhaare wachsen zu lassen, sowie das damit einhergehende Unbehagen darauf, eine drohende Erfahrung der Fremdheit mir selbst gegenüber abwenden zu wollen. Zu einer solchen Fremderfahrung würde es kommen, wenn ich durch meine Körperhaare damit konfrontiert werde, dass ich mir fremd bin. Jedoch um sich selbst kennenzulernen sind Menschen nach phänomenologischem Verständnis (vgl. Meyer-Drawe 2001: 141-142) auf andere Menschen angewiesen, da sie sich selbst erst durch andere bewusst werden können. Doch stellt es angesichts des gelebten Ideals der Haarlosigkeit (vgl. Labre 2002: 120-122, Strmljan 2018: 406) eine Herausforderung dar, meine drohende Fremderfahrung, aufgrund der Konfrontation mit meinen Körperhaaren, im Kontakt mit anderen Menschen zu überwinden, sodass ich eine solche Fremderfahrung vermeide, indem ich meine Körperhaare entferne. Als Resultat verbleibt mein Unbehagen darüber, dem Ideal der Haarlosigkeit zu entsprechen.
Zu einer solchen Antwort gelange ich anhand einer Studie, die folgender Forschungsfrage folgt:
Wie erfahren sich Menschen beim Waxing in einem Kosmetikstudio unter den Bedingungen der binären Geschlechterordnung?
Dass die Erfahrungen in einem Kosmetikstudio erforscht werden, begründet sich damit, dass in einem solchen der Zugang zu Erfahrungen bei der Entfernung von Körperhaaren möglich wird. Körperhaare zu entfernen ist zwar ein alltäglicher Umgang mit Körpern, jedoch intim und persönlich, sodass ein Zugang schwierig wird. Eine Lösung stellt hierfür ein Kosmetikstudio dar. Als Praktikantin in dem Kosmetikstudio Beautystudio werden mir Erfahrungen beim Waxing – einer kosmetischen Technik der Haarentfernung – zugänglich.
Auf solche Weise Daten zu erheben folgt dem ethnographischen Vorgehen der teilnehmenden Beobachtung. Forscher*innen nehmen beobachtend vor Ort teil und erheben Daten, indem sie Notizen, Protokolle und schließlich Studien erstellen. Mittels eines solchen Forschungsstils können Forscher*innen Erfahrungen in einer Studie zentral setzen, da sie so Erfahrungen selbst machen können und Zugang zu den Erfahrungen anderer erhalten (vgl. Amann/ Hirschauer 1997: 29-30, Breidenstein et al. 2013: 86-87, 103, 177-178).
Im Zuge der Datenerhebung zeigt sich wiederum, dass im Umgang mit Körperhaaren die Bedingungen der binären Geschlechterordnung wirksam werden. Beispielsweise wird in vielen Situationen die dichotome Differenz zwischen Männern und Frauen betont, ohne dass es konkret für die kosmetische Anwendung notwendig zu sein scheint. So erklärt sich, dass für die Analyse und das Hinterfragen der zur Sprache gebrachten Erfahrungen ein geschlechtertheoretisches Konzept herangezogen wird, welches Erfahrungen hinsichtlich der Bedingungen der binären Geschlechterordnung befragen kann. Eine solche Betrachtung der Daten bietet Gesa Lindemanns Konzept „Der leiblich-affektiven Konstruktion des Geschlechts“ (1992).
Basierend auf dem feministisch-phänomenologischen Erfahrungsbegriff, dem ethnographischen Vorgehen und dem Geschlechterkonzept Lindemann zeigt sich, dass Menschen beim Waxing erfahren (können), mit anderen Menschen verbunden und sich selbst unverbunden zu sein. Dabei wird die Haut zum Kristallisationspunkt der Verbindung zu anderen Menschen (und auch Apparaten). Durch die Berührungen wird einerseits Verbundenheit gestaltet und eine gegenseitige Zuwendung erfahrbar, andererseits wird diese aber auch unterbrochen, wenn durch das Waxing Schmerz zugefügt wird oder Menschen durch Blicke entblößt werden. So wird die Haut zum Medium zwischen den Erfahrungen der Verbundenheit und Unverbundenheit.
(Hinweisen möchte ich an dieser Stelle, dass alle Namen und Orte anonymisiert sind. Demnach handelt es sich beim Beautystudio um den anonymisierten Namen des Kosmetikstudios, in welchem ich forschte. Auf diese Weise soll die Persönlichkeit der Kontaktpersonen im Feld gewahrt bleiben.)
Literaturhinweise:
Alcoff, Linda M. (1997): Phänomenologie, Poststrukturalismus und feministische Theorie. Zum Begriff der Erfahrung. In: Stoller, Silvia/ Vetter, Helmuth (Hg.): Phänomenologie und Geschlechterdifferenz. Wien: WUV-Universitäts-Verlag: 227-271.
Amann, Klaus/ Hirschauer, Stefan (1997): Die Befremdung der eigenen Kultur. Ein Programm. In: Hirschauer, Stefan/ Amann, Klaus (Hg.): Die Befremdung der eigenen Kultur: Zur ethnographischen Herausforderung soziologischer Empirie. Frankfurt am Main: Suhrkamp Verlag: 7-52.
Breidenstein, Georg/ Hirschauer, Stefan/ Kalthoff, Stefan/ Nieswand, Boris (2013): Ethnografie. Die Praxis der Feldforschung. Konstanz & München: UVK Verlagsgesellschaft
Labre Peixoto, Magdala (2002): The Brazilian Wax: New Hairlessness Norm for Women? In: Journal of Communication Inquiry: 26 (2): 113-132.
Lindemann, Gesa (1992): Die leiblich-affektive Konstruktion des Geschlechts. Für eine Mikrosoziologie des Geschlechts unter der Haut. In: Zeitschrift für Soziologie: 21 (5): 330-346.
Meyer-Drawe, Käte (2001): Leiblichkeit und Sozialität. München: Wilhelm Fink Verlag.
Stoller, Silvia (2005): Zur poststrukturalistischen Kritik an der Erfahrung im Kontext der feministischen Philosophie. In: Stoller, Silvia/ Vasterling, Veronica/ Fisher, Linda (Hg.): Feministische Phänomenologie und Hermeneutik. Würzburg: Königshausen & Neumann GmbH: 139-170.
Strmljan, Alina (2018): Haare zum Schämen? Weibliche Körperbehaarung und ihre Entfernung – Normen, Tabus und Trivialisierungen. In: Breuss, Susanne (Hg.): Mit Haut und Haar. Frisieren, Rasieren, Verschönern. Wien: Metroverlag: 404-410.
In this thesis we examined the question whether personality traits of early child care workers influence process quality in preschool.
Research has shown that in educational settings such as preschool, pedagogical quality affects children’s developmental outcome (e.g. NICHD, 2002; Peisner-Feinberg et al., 1999). A substantial part of pedagogical quality known to be vital in this respect is the interaction between teacher and children (e.g., Tietze, 2008). Results of prior classroom research indicate that the teachers’ personality might be an important factor for good teacher-child-interaction (Mayr, 2011). Thus, personality traits might play a vital role for the interaction in preschool. Therefore, the aims of this thesis were to a) identify pivotal personality traits of child care workers, b) assess ideal levels of the identified personality traits and c) examine the relationship between pivotal personality traits and process quality. On that account, we conducted two requirement analyses and a video study. The results of these studies showed that subject matter experts (parents, child care workers, lecturers) partly agreed as to which personality traits are pivotal for child care workers. Furthermore, the experts showed high consensus with regard to the minimum, ideal and maximum personality trait profiles. Furthermore, child care workers whose profiles lay closer to the experts’ ideal also showed higher process quality. In addition, regression analyses showed that the child care workers’ levels of the Big Two (Communion and Agency) related significantly to their process quality.
Spektroskopie zweiatomiger Moleküle bei Einstrahlung ultrakurzer Laserpulse und ihre Anwendung
(2020)
Even with moderate pulse energies and average powers, ultrashort pulse lasers achieve very high peak powers, whose effect on matter is fundamentally different from that of other light sources. The high electric field strength does not only cause an increase of optically nonlinear effects such as second harmonic generation, but it is also responsible for the “cold“ ablation, which leads to colder plasmas. An investigation of these two circumstances in terms of a simplification of the pulse duration measurement and an improvement of the molecular formation in cooling plasmas is the topic of this work. In this context, it is shown that when selecting suitable process parameters, especially when purposefully defocusing the medium, the use of ultrashort pulse lasers improves the spectroscopy of several emitting molecules such as aluminum oxide. Therefore, their detection is possible even without the time-resolving spectrometers required in literature. In addition, ultrashort pulses enable spatially resolved crystallization of zinc oxide on zinc surfaces prepared by basic means. The resulting wurtzites usually align their c-axis approximately perpendicular to the underlying surface and can be used to generate scattered second harmonics. Fiber-based femtosecond lasers with pulse energies in the microjoule range, pulse durations of a few 100fs and very low maintenance requirements have proven to be a powerful instrument for these purposes. For measuring the pulse duration, the high pulse energy also enables the usage of frequency doublers with much lower conversion eciencies. Despite nonuniform crystal axes, the scattering second harmonic generating aluminum nitride has proven to be particularly suitable for optical autocorrelation. Compared to the commonly used monocrystalline beta-barium borate, the sintered aluminum nitride ceramic plates facilitate the adjustment, simplify the material handling and reduce the expenses by two to three orders of magnitude. The method developed in this work is therefore also suitable for confirmatory measurements of the pulse duration during the production process of such systems – especially when the occurring pulse energies are high or rather too high for beta-barium borate.
The history of human kind is characterized by social conflict. Every conflict can be the starting point of social change or the escalation into more destructive forms. The social conflict in regard to rising numbers of refugees and their acceptance that arose in most host countries in 2015 already took on destructive forms – in Germany, right-wing extremists attacked refugee shelters and even killed multiple people, including political leaders who openly supported refugees. Thus, incompatible expectancies and values of different parts of the society led to violent action tendencies, which tremendously threaten intergroup relations. Psychological research has developed several interventions in past decades to improve intergroup relations, but they fall short, for example, when it comes to the inclusion of people with extreme attitudes and to precisely differentiate potential prosocial outcomes of the interventions. Thus, this dissertation aimed to a) develop psychological interventions, that could also be applied to people with more extreme attitudes, thereby putting a special emphasis on collecting a diverse sample; b) gain knowledge about target- and outcome specific effects: Who benefits from which intervention and how can specific prosocial actions be predicted in order to develop interventions that guide needs-based actions; and c) shed light on potential underlying mechanisms of the interventions.
The dissertation will be introduced by the socio-political background that motivated the line of research pursued, before providing an overview of the conceptualization of social conflicts and potential psychological inhibitors and catalyzers for conflict transformation. Based on past research on socio-psychological interventions and their limitations, the aims of the dissertation will be presented in more detail, followed by a short summary of each manuscript. Overall, the present thesis comprises four manuscripts that were summarized in the general discussion into a road map for social-psychological interventions to put them into a broader perspective. The road map aspires to provide recommendations for increasing – either approach-oriented or support-oriented actions – by the socio-psychological interventions for a variety of host society groups depending on their pre-existing attitude towards refugees.
A Paradoxical Intervention targeting central beliefs of people with negative attitudes towards refugees influenced inhibitory and catalyzing factors for conflict transformation over the course of three experiments – thereby providing an effective tool to establish approach-oriented action tendencies, such as the willingness to get in contact with refugees. Further, the dissertation presents a novel mechanism – namely Cognitive Flexibility – which could explain the Paradoxical Interventions’ effect of past research. By positively affecting a context-free mindset, the Paradoxical Intervention could impact more flexible thought processes in general, irrespective of the topic tackled in the Paradoxical Intervention itself. For people with rather positive attitudes addressing emotions may increase specific support-oriented action tendencies. The dissertation provides evidence of a positive relation between moral outrage and hierarchy-challenging actions, such as solidarity-based collective action, and sympathy with prosocial hierarchy-maintaining support-oriented actions, such as dependency-oriented helping. These exclusive relations between specific emotions and action intentions provide important implications for the theorizing of emotion-behavior relations, as well as for practical considerations. In addition, a diversity workshop conducted with future diplomats showed indirect effects on solidarity-based collective action via diversity perception and superordinate group identification, thereby extending past research by including action intentions and going beyond the focus on grassroot-initiatives by presenting an implementable intervention for future leaders in a real world context.
Taken together, this dissertation provides important insights for the development of socio-psychological interventions. By integrating a diverse sample, including members of institutions on meso- and macro-levels (non-governmental organizations and future politicians) of our society, this dissertation presents a unique multi-perspective of host society members on the social conflict of refugee acceptance and support. Thereby, this work contributes to theoretical and practical advancement of how social psychology can contribute not only to negative peace – by for example (indirectly) reducing support of violence against refugees – but also to positive peace – by for example investigating precursors of hierarchy-challenging actions that enable equal rights.
The scientific interest in nonsuicidal self-injury (NSSI) has increased in the last two decades. High prevalence and comorbidity rates, low quality of life and increased risk of suicidality highlight the importance of this research field. The present thesis focuses on intra- and interpersonal factors associated with the development and maintenance of NSSI.
The aim of study 1 was the examination of personality traits of adolescents with NSSI without Borderline Personality Disorder (NSSI-BPD), adolescents with NSSI and BPD (NSSI+BPD), clinical controls (CC) and nonclinical controls (NC). Results showed that adolescents with NSSI disorder scored significantly higher on novelty seeking and harm avoidance and lower on persistence, self-directedness, and cooperativeness than CC. In adolescents with NSSI+BPD this personality pattern was even more pronounced than in adolescents with NSSI-BPD.
Adolescents´ NSSI leads to distress that affects the whole family system, often resulting in conflicts and disrupted family communication and functioning. Parents report feelings of distress, insecurity and helplessness. Adolescents with NSSI report more parental criticism and control and less support than adolescents without NSSI. Study 2 investigated the parenting behavior in families of adolescents with NSSI. Adolescents with NSSI reported less maternal warmth and support than NC adolescents. Mothers of adolescents with NSSI showed higher psychopathology scores than NC mothers and less parental satisfaction than CC and NC mothers.
Siblings are also reported to suffer from changes in family dynamics. The aim of study 3 was to examine the sibling relationship quality of adolescents with NSSI, CC and NC. Siblings reported a wide range of negative emotional and familial consequences as a result of their sister´s NSSI. Siblings of adolescents with NSSI experienced significantly more coercion in the relationship with their sister compared to CC and NC siblings. Adolescents with NSSI reported significantly less warmth and empathy in the sibling relationship and higher rivalry scores between their siblings and themselves than NC adolescents. For both, adolescents with NSSI and their siblings, associations were found between sibling relationship quality and internalizing problems.
Study 4 aimed to further explore the family emotional climate. Therefore, the level of expressed emotion (EE) was assessed in adolescents with NSSI, CC, NC and their mothers. Parental high EE (HEE) is linked to adolescent NSSI, especially parental criticism seems to be strongly associated with NSSI. Previous research into NSSI and EE has focused on parental EE, however, the conceptualization of EE as a unidirectional construct from parent to child may present an incomplete picture. Therefore, the current study included both, adolescent and maternal EE. Adolescents in the NSSI and CC group more often met criteria for HEE than NC. Adolescents with NSSI exhibited significantly more covert criticism and critical tone toward their mothers than CC and NC. HEE of adolescents with NSSI was associated with a range of difficulties in emotion regulation. For the total sample, moderate concordance was found between adolescents and mothers EE-status.
The research presented in this thesis has important clinical implications. The differences in personality traits of adolescents with NSSI with and without BPD underline the need for a dimensional personality assessment as well as specific treatment programs for adolescents with NSSI-BPD. Problems within the family are frequent triggers for NSSI. Therefore, interventions for adolescents with NSSI should include both, the improvement of emotion regulation and family interaction and communication. Along with the reduction of negative relationship aspects, psychotherapy should also focus on the enhancement of positive relationship quality. The emotional burden of family members stresses the need for emotional and practical support for parents and siblings.
In the context of augmented reality we define tracking as a collection of methods to obtain the position and orientation (pose) of a user. By means of various displaying techniques, this ensures a correct visual overlay of graphical information onto the reality perceived. Precise results for calculation of the camera pose are gained by methods of image processing, usually analyzing the pixels of an image and extracing features, which can be recognized over the image sequence. However, these methods do not regard the process of image synthesis or at least in a very simplyfied way. In contrast, the class of model-based methods assumes a given 3D model of the observed scene. Based on the model data features can be identified to establish correspondences in the camera image. From these feature correspondences the camera pose is calculated. An interesting approach is the strategy of analysis-by-synthesis, regarding the computer graphics rendering process for extending the knowledge about the model by information from image synthesis and other environment variables.
In this thesis the components of a tracking system are identified and further it is analyzed, to what extend information about the model, the rendering process and the environment can contribute to the components for improvement of the tracking process using analysis-by-synthesis. In particular, by using knowledge as topological information, lighting or perspective, the feature synthesis and correspondence finding should lead to visually unambiguous features that can be predicted and evaluated to be suitable for stable tracking of the camera pose.
Die Studien der vorliegenden Arbeit untersuchen geschlechtsspezifisch-emotionale Reaktionsmuster auf stärkere und weniger stark emotionalisierte Texte verschiedener Textarten zu negativen Themen. Zusätzlich finden verschiedene Ausprägungen von Geschlechterstereotypen und dahingehend mögliche Zusammenhänge mit emotionalen Reaktionen Berücksichtigung. Versuchspersonen wurden mit Textmaterial konfrontiert und sollten daraufhin mit Hilfe des Emotionsfragebogens M-DAS ihre emotionalen Reaktionen bewerten. Frauen zeigten eine stärkere Ergriffenheit in Bezug auf das Textmaterial im Allgemeinen und besonders auf emotionalisiertes Textmaterial. Gemischte Ergebnisse zeigten sich in Bezug auf geschlechtertypische Textarten. Eine Sachtextpräferenz der Männer ließ sich ebensowenig signifikant belegen wie die erwartete stärkere Vorliebe der Frauen für literarische Texte. Geschlechtsspezifische Emotionen wurden weitestgehend erwartungskonform berichtet: Frauen reagierten mit stärkerer Angst und Trauer auf das Textmaterial, Männer mit stärkerer Verachtung. Die Ergebnisse in Bezug auf Wut sind gemischt, in einigen Fällen wurde Wut jedoch stärker von den Frauen berichtet. Die Untersuchung der Zusammenhänge zwischen internalisierten Stereotypen ergab Einflüsse hauptsächlich von weiblichen Stereotypen auf emotionale Reaktionen, männliche Stereotype konnten nur in einer Teilfragestellung als Einflussfaktor ausgemacht werden. Emotionsbezogene Stereotype wiesen keine Zusammenhänge mit emotionalen Reaktionen auf. Insgesamt belegen die Ergebnisse der Arbeit, dass sich geschlechterspezifische Unterschiede in emotionalen Reaktionen finden lassen.
Initial goal of the current dissertation was the determination of image-based biomarkers sensitive for neurodegenerative processes in the human brain. One such process is the demyelination of neural cells characteristic for Multiple sclerosis (MS) - the most common neurological disease in young adults for which there is no cure yet. Conventional MRI techniques are very effective in localizing areas of brain tissue damage and are thus a reliable tool for the initial MS diagnosis. However, a mismatch between the clinical fndings and the visualized areas of damage is observed, which renders the use of the standard MRI diffcult for the objective disease monitoring and therapy evaluation. To address this problem, a novel algorithm for the fast mapping of myelin water content using standard multiecho gradient echo acquisitions of the human brain is developed in the current work. The method extents a previously published approach for the simultaneous measurement of brain T1, T∗ 2 and total water content. Employing the multiexponential T∗ 2 decay signal of myelinated tissue, myelin water content is measured based on the quantifcation of two water pools (myelin water and rest) with different relaxation times. Whole brain in vivo myelin water content maps are acquired in 10 healthy controls and one subject with MS. The in vivo results obtained are consistent with previous reports. The acquired quantitative data have a high potential in the context of MS. However, the parameters estimated in a multiparametric acquisition are correlated and constitute therefore an ill-posed, nontrivial data analysis problem. Motivated by this specific problem, a new data clustering approach is developed called Nuclear Potential Clustering, NPC. It is suitable for the explorative analysis of arbitrary dimensional and possibly correlated data without a priori assumptions about its structure. The developed algorithm is based on a concept adapted from nuclear physics. To partition the data, the dynamic behavior of electrically even charged nucleons interacting in a d-dimensional feature space is modeled. An adaptive nuclear potential, comprised of a short-range attractive (Strong interaction) and a long-range repulsive term (Coulomb potential), is assigned to each data point. Thus, nucleons that are densely distributed in space fuse to build nuclei (clusters), whereas single point clusters are repelled (noise). The algorithm is optimized and tested in an extensive study with a series of synthetic datasets as well as the Iris data. The results show that it can robustly identify clusters even when complex configurations and noise are present. Finally, to address the initial goal, quantitative MRI data of 42 patients are analyzed employing NPC. A series of experiments with different sets of image-based features show a consistent grouping tendency: younger patients with low disease grade are recognized as cohesive clusters, while those of higher age and impairment are recognized as outliers. This allows for the definition of a reference region in a feature space associated with phenotypic data. Tracking of the individual's positions therein can disclose patients at risk and be employed for therapy evaluation.
Abdriftbedingte Pflanzenschutzmittelrückstände in unbehandelten Kulturen auf angrenzenden Flächen
(2020)
Die vorliegende Arbeit beschäftigt sich mit der Abdrift von Pflanzenschutzmitteln (PSM), die auf Lebensmittelkulturen in angrenzenden Flächen, insbesondere in benachbarte Haus- und Kleingärten, gelangt. In einer Reihe von Windtunnelversuchen wurde die Abdrift von PSM aus Flächen- und Raumkulturen während der Applikation mit zwei verschiedenen Testsystemen nachgestellt. Das Testsystem Flächenkultur simuliert die Applikation auf Flächenkulturen, das Testsystem Raumkultur die auf Raumkulturen. Auf der Nicht-Zielfläche wurden die auf Grund von Abdrift entstandenen Rückstände des verwendeten Tracers Pyranin nach der Applikation entfernungsabhängig auf den Lebensmittelkulturen Kopfsalat, Erdbeeren und Tomaten gemessen. Durch die gleichzeitige Messung der Bodendeposition konnten die Messwerte mit Hilfe von Regressionsgleichungen (R² = 0,88 bis 0,97) in Bezug zu den Abdrifteckwerten (AEW) gebracht werden. Dadurch war es möglich, erste Abschätzungen der Höhe von Rückständen vorzunehmen, die über Abdrift von landwirtschaftlichen Flächen auf benachbarte Lebensmittelkulturen im Freiland gelangen können. Diese Abschätzung ist zunächst limitiert auf die drei Versuchspflanzen. Die Versuche zeigen, dass sich die meisten durch Abdrift entstehenden Rückstände auf Salatköpfen wieder finden, gefolgt von Erdbeeren und Tomaten.
Neben dem experimentellen Teil wurden Analysen mit Geoinformationssystemen (GIS) durchgeführt, um die Nachbarschaftsverhältnisse zwischen landwirtschaftlich genutzten Flächen und Gartenflächen für ganz Deutschland und speziell für Rheinland-Pfalz (RLP) zu analysieren. Dazu wurden für die deutschlandweiten Berechnungen die Daten des amtlichen topographisch-kartographischen Informationssystems (ATKIS) und für die RLP-weiten Berechnungen die Daten des amtlichen Liegenschaftskatasterinformationssystem (ALKIS) verwendet. Beachtet werden muss, dass auf Grund der Datenbeschaffenheit eine Abgrenzung der Gartenflächen zu Wohnflächen nicht möglich ist. Deutschlandweit liegen etwa 1,1 % aller potentiellen Gartenflächen innerhalb eines 5 m Pufferbereichs um Raumkulturen bzw. innerhalb eines 2 m Pufferbereichs um Flächenkulturen. Für RLP sind es 0,75 %. Mit Hilfe eines Landbedeckungsdatensatzes der Fa. RLP AgroScience GmbH und den ALKIS-Daten konnte jedoch die exakte Gartenfläche für RLP auf 47.437 ha bestimmt werden. Basierend auf dieser Datengrundlage liegen 1,2 % der Gartenfläche von RLP innerhalb der genannten Pufferbereiche. Des Weiteren ergaben Berechnungen, dass 3 % der Gärten in RLP direkt angrenzend zu landwirtschaftlich genutzten Flächen liegen.
Im Rahmen dieser Arbeit wurden nicht nur Gärten betrachtet, die an landwirtschaftliche Flächen grenzen, sondern auch Nachbarschaftsverhältnisse zwischen ökologisch und konventionell bewirtschafteten Flächen untersucht. Diese Berechnungen erfolgten mit den Daten des Integrierten Verwaltungs- und Kontrollsystems (InVeKoS). Insgesamt grenzen in RLP 47,1 % aller ökologisch bewirtschafteten Flächen unmittelbar an konventionell bewirtschaftete Flächen an.
Stream ecosystems are one of the most threatened ecosystems worldwide due to their exposure to diverse anthropogenic stressors. Pesticides appear to be the most relevant stressor for agricultural streams. Due to the current mismatch of modelled and measured pesticide concentrations, monitoring is necessary to inform risk assessment or improve future pesticide approvals. Knowing if biotic stress responses are similar across large scales and long time frames could ultimately help in estimating protective stressor thresholds.
This thesis starts with an overview of entry pathways of pesticides to streams as well as the framework of current pesticide monitoring and gives an outline of the objectives of the thesis. In chapter 2, routine monitoring data based on grab sampling from several countries is analysed to identify the most frequently occurring pesticide mixtures. These mixtures are comprised of relatively low numbers of pesticides, of which herbicides are dominating. The detected pesticide mixtures differ between regions and countries, due to differences in the spectrum of analysed compounds and limits of quantification. Current routine monitoring does not include sampling during pesticide peaks associated with heavy rainfall events which likely influences the detected pesticide mixtures. In chapter 3, sampling rates of 42 organic pesticides for passive sampling are provided together with recommendations for the monitoring of field-relevant peaks. Using this information, in chapter 4 a pesticide gradient is established in an Eastern European region where agricultural intensity adjacent to sampled streams ranges from low to high. In contrast to current routine monitoring, rainfall events were sampled and a magnitude of pesticides were analysed. This led to the simultaneous detection of numerous pesticides of which one to three drive the pesticide toxicity. The toxicity, however, showed no relationship to the agricultural intensity. Using microcosms, the stress responses of fungal communities, the hyphomycetes, and the related ecosystem function of leaf decomposition, is investigated in chapter 5. Effects of a field-relevant fungicide mixture are examined across three biogeographical regions for three consecutive cycles of microbial leaf colonisation and decomposition. Despite different initial communities, stress responses as well as recoveries were similar across biogeographical regions, indicating a general pattern.
Overall, this thesis contributes to an improved understanding of occurrence and concentrations of pesticides mixtures in streams, their monitoring and impact on an ecosystem function. We showed that estimated pesticide toxicities reach levels that affect non-target organisms and thereby potentially whole ecosystems. Routine monitoring, however, likely underestimates the threat by pesticides. Effects leading to a loss in biodiversity or functions in streams ecosystems can be reduced by reassessing approved pesticides with ongoing targeted monitoring and increased knowledge of effects caused by these pesticides.
In dieser Arbeit werden die schottischen Liedbearbeitungen Ludwig van Beethovens auf ihre möglichen gälischen Vorläufer untersucht und in ihrem historischen Kontext aus einer gälischen Perspektive betrachtet. Ihre Liedbiographien werden um Vorläufer ergänzt und vervollständigt, die vom dem schottischen Auftraggeber Beethovens, George Thomson teilweise vorsätzlich unterschlagen wurden. Gründe hierfür sind in der politischen und kulturellen Unterdrückung der gälischen Sprachgemeinschaft Schottlands zu finden. Handelt es sich wirklich um anonyme Volkslieder, oder auch um Kompositionen bekannter Musiker aus der gälischen Kultur? Welche Veränderungen erfuhren sie im Zuge der Anonymisierung und der Degradierung zur Volksmusik, sowie der anschließenden Neuausrichtung in der schottischen Nationalmusik? Zu 12 der schottischen Lieder Beethovens sind ausführliche Liedbiographien mit allen gälischen Liedtexten, deutscher Übersetzung und den historischen Hintergründen der gälischen Vorläufer und ihrer Notierungen entstanden.
The three biodegradable polymers polylactic acid (PLA), polyhydroxybutyrate (PHB) and polybutylene adipate terephthalate (PBAT) were coated with hydrogenated amorphous carbon layers (a-C:H) in the context of this thesis. A direct alignment of the sample surface to the source was chosen, resulting in the deposition of a robust, r-type a-C:H. At the same time, a partly covered silicon wafer was placed together with the polymers in the coating chamber and was coated. Silicon is a hard material and serves as a reference for the applied layers. Due to the hardness of the material, no mixed phase occurs between the substrate and the applied layer (no interlayer formation). In addition, the thickness of the applied layer can be estimated with the help of the silicon sample.
The deposition of the layer was realized by radio frequency plasma enhanced chemical vapor deposition (RF-PECVD). For the coating the samples were pre-treated with an oxygen plasma. Acetylene was used as precursor gas for the plasma coating. Coatings with increasing thickness in 50 nm steps from 0-500 nm were realised.
The surface analysis was performed using several techniques: The morphology and layer stability were analyzed with scanning electron microscopy (SEM) measurements. The wettability was determined by contact angle technique. In addition, the contact angles provide macroscopic information about the bond types of the carbon atoms present on the surface. For microscopic analysis of the chemical composition of the sample and layer surfaces, diffuse reflectance Fourier transform infrared spectroscopy (DRIFT) as well as synchrotron based X-ray photon spectroscopy (XPS) and near edge X-ray absorption fine structure spectroscopy (NEXAFS) were used.
All coated polymers showed several cases of layer failure due to internal stress in the layers. However, these were at different layer thicknesses, so there was a substrate effect. In addition, it is visible in the SEM images that the coatings of PLA and PHB can cause the applied layer to wave, the so-called cord buckling. This does not occur with polymer PBAT, which indicates a possible better bonding of the layer to the polymer. The chemical analyses of the layer surfaces show for each material a layer thickness dependent ratio of sp² to sp³ bonds of carbon, which alternately dominate the layer. In all polymers, the sp³ bond initially dominates, but the sp² to sp³ ratio changes at different intervals. Although the polymers were coated in the same plasma, i.e. the respective layer thicknesses (50 nm, 100 nm, ...) were applied in the same plasma process, the respective systems differed considerably from each other. A substrate effect is therefore demonstrably present. In addition, it was found that a change in the dominant bond from sp³ to sp² is an indication ofan upcoming layer failure of the a-C:H layer deposited on the polymer. In the case of PLA, this occurs immediately with change to sp² as the dominant bond; in the case of PHB and PBAT, this occurs with different delay to increased layer thicknesses (at PHB 100 nm, at PBAT approx. 200 nm.
Overall, this thesis shows that there is a substrate effect in the coating of the biodegradable polymers PLA, PHB and PBAT, since despite the same coating there is a different chemical composition of the surface at the respective layer thicknesses. In addition, a layer failure can be predicted by analyzing the existing bond.
Studies in recent years have demonstrate adolescents and young adults to have a deficient data protection competence, however children and adolescents between the ages of ten and 13 were mostly not focus of these studies. Therefore, the guiding question of the work is how data protection competence is developed in children and adolescents at a young age in order to be able to infer suitable, educational concepts for this age group. At the beginning of the work, a data protection competence model is derived from a media competence model, which serves as the basis for the further field investigation. A survey was carried out at general secondary schools in Rhineland-Palatinate, which shows that the respondents still have sufficiently developed Risk Assessment Competence, but were insufficiently developed in terms of knowledge, Selection and Usage Competence and the Implementation Competence. Recommendations for actions are given in the last part of the work – containing learning goal descriptions to be possibly implemented in an educational framework – in order to address this issue.
Data-minimization and fairness are fundamental data protection requirements to avoid privacy threats and discrimination. Violations of data protection requirements often result from: First, conflicts between security, data-minimization and fairness requirements. Second, data protection requirements for the organizational and technical aspects of a system that are currently dealt with separately, giving rise to misconceptions and errors. Third, hidden data correlations that might lead to influence biases against protected characteristics of individuals such as ethnicity in decision-making software. For the effective assurance of data protection needs,
it is important to avoid sources of violations right from the design modeling phase. However, a model-based approach that addresses the issues above is missing.
To handle the issues above, this thesis introduces a model-based methodology called MoPrivFair (Model-based Privacy & Fairness). MoPrivFair comprises three sub-frameworks: First, a framework that extends the SecBPMN2 approach to allow detecting conflicts between security, data-minimization and fairness requirements. Second, a framework for enforcing an integrated data-protection management throughout the development process based on a business processes model (i.e., SecBPMN2 model) and a software architecture model (i.e., UMLsec model) annotated with data protection requirements while establishing traceability. Third, the UML extension UMLfair to support individual fairness analysis and reporting discriminatory behaviors. Each of the proposed frameworks is supported by automated tool support.
We validated the applicability and usability of our conflict detection technique based on a health care management case study, and an experimental user study, respectively. Based on an air traffic management case study, we reported on the applicability of our technique for enforcing an integrated data-protection management. We validated the applicability of our individual fairness analysis technique using three case studies featuring a school management system, a delivery management system and a loan management system. The results show a promising outlook on the applicability of our proposed frameworks in real-world settings.
Amphibian populations are declining worldwide for multiple reasons such as habitat destruction and climate change. An example for an endangered European amphibian is the yellow-bellied toad Bombina variegata. Populations have been declining for decades, particularly at the northern and western range margin. One of the extant northern range centres is the Westerwald region in Rhineland-Palatinate, Germany. To implement informed conservation activities on this threatened species, knowledge of its life-history strategy is crucial. This study therefore focused on different developmental stages to test predictions of life-history theory. It addressed (1) developmental, (2) demographic and (3) genetic issues of Bombina variegata as a model organism: (1) Carry-over effects from larval environment to terrestrial stages and associated vulnerability to predators were investigated using mesocosm approaches, fitness tests and predation trials. (2) The dynamics and demography of B. variegata populations were studied applying a capture-mark-recapture analysis and skeletochronology. The study was complemented through (3) an analysis of genetic diversity and structuring of B. variegata populations using 10 microsatellite loci. In order to reveal general patterns and characteristics among B. variegata populations, the study focused on three geographical scales: local (i.e. a former military training area), regional (i.e. the Westerwald region) and continental scale (i.e. the geographical range of B. variegata). The study revealed carry-over effects of larval environment on metamorph phenotype and behaviour causing variation in fitness in the early terrestrial stage of B. variegata. Metamorph size and condition are crucial factors for survival, as small-sized individuals were particularly prone to predator attacks. Yellow-bellied toads show a remarkable fast-slow continuum of the life-history trait longevity. A populations’ position within this continuum may be determined by local environmental stochasticity, i.e. an extrinsic source of variation, and the efficiency of chemical antipredator protection, i.e. an intrinsic source of variation. Extreme longevity seems to be an exception in B. variegata. Senescence was absent in this study. Weather variability affected reproductive success and thus population dynamics. The dispersal potential was low and short-term fragmentation of populations caused significant genetic differentiation at the local scale. Long-term isolation resulted in increased genetic distance at the regional scale. At the continental scale, populations inhabiting the marginal regions were deeply structured with reduced allelic richness. As consequence of environmental changes, short-lived and isolated B. variegata populations at the range margin may face an increased risk of extinction. Conservation measures should thus improve the connectivity among local populations and reinforce annual reproductive success. Further research on the intraspecific variation in B. variegata skin toxins is required to reveal potential effects on palatability and thus longevity.
Microbial pollution of surface waters poses substantial risks for public health, amongst others during recreational use. Microbial pollution was studied at selected sampling sites in rivers Rhine, Moselle and Lahn (Germany) on the basis of commonly used fecal indicator organisms (FIO) indicating bacterial (Escherichia coli, intestinal enterococci) and viral (somatic coliphages) fecal contamination. In addition, blaCTX-Mantibiotic resistance genes (ARG) were quantified at twosites in river Lahn and were used as markers for tracking the spread of antibiotic resistance in the aquatic environment. The impact of changes in climate-related parameters on FIO was examined by studying monitoring results of contrasting flow conditions at rivers Rhine and Moselle. Analyses at all studied river sites clearly indicate that high discharge and precipitation enhance the influx of FIO, ARG and thus potentially (antibiotic resistant) pathogens into rivers. In contrast, a decrease in hygienic microbial pollution was observed under high solar irradiation and increasing water temperatures. Based on identified contributing key factors, multiple linear regression (MLR) models for five sites at a stretch of river Lahn were established that allow a timely assessment of fecal indicator abundances. An interaction between abiotic and biotic factors (i.e. enhanced grazing pressure) considerably contributed to the formation of seasonal patterns among FIO abundances. This was enhanced during extraordinary low flow conditions in rivers with pronounced trophic interactions, clearly hampering a transfer of model approaches between rivers of different biological and hydrological characteristics. Bacterial indicatorswere stronger influenced by grazing pressure than phages. Hence, bacterial indicators alone do not sufficiently describe viral pollution in rivers. BlaCTX-Mgenes were omnipresent in Lahn River water and corresponded to distribution patterns of FIO, indicating fecal sources. Agriculture and waste watertreatment plant effluents contributed to ARG loads and participants in non-bathing water sports were found to be at risk of ingesting antibiotic resistant bacteria (ARB) including ARG, bearing the risk of infection or colonization. Results of the present study highlight the need to be aware of such risks not only in designated bathing waters. ARG abundance at both riverine sampling sites could largely be explained by E. coliabundance and may thus also be incorporated into multiple regression models using E. colispecific environmental predictors. It can be expected that the frequency of short-term microbial pollution events will increase over the next decades due to climate change. Several challenges were identified with regard to the implementation of early warning systems to protect the public from exposure to pathogens in rivers. Most importantly, the concept of the Bathing Water Directive (Directive 2006/7/EC) itself as well as the lack of harmonization in the regulatory framework at European Union (EU) level are major drawbacks and require future adjustments to reliably manage health risks related to microbial water pollution in waters used in multifunctional ways.
This dissertation presents the application of the molecular LIBS method, a novelapproach of Laser-Induced Breakdown Spectroscopy (LIBS), to optimize the detection of pitting chlorides in concrete structures, which are e.g. contaminated bydeicing salt in winter. Potentiometric titration as the standard method for chloride determination in building material analysis is costly and time-consuming. Ithas the decisive disadvantage that the determination of chloride concentrationis based on the total mass of the concrete and not on the cement content asrequired by the European standard EN 206. The imaging capabilities of LIBS forphase separation of the concrete meet this requirement. LIBS was already usedby BAM in 1998 in building material analysis, but the detection of chlorides withLIBS requires expensive helium purging and spectrometers outside the visiblespectral range to detect emissions of atomic chlorine. The approach of molecular LIBS is to quantify the emission of chloride-containing molecular radicalsformed during the cooling phase of the laser-induced plasma. The advantagescompared to conventional LIBS method are the emission in the visible spectralrange and the applicability without noble gas purging. In this thesis the influenceof the experimental components on the time behaviour of the relevant molecularemission bands is investigated, signal deviations due to plasma fluctuations aresignificantly reduced and for plasma analysis the molecular formation is simulated on atomistic scales and compared with standard methods. In simultaneousmeasurements, atomic and molecular Cl emission are directly compared and the quantification is optimized by data combination. Molecular LIBS will be extended to a quantifying and imaging method that can detect chlorides withoutnoble gas purging.
Lastkraftwagen werden weltweit in verschiedenen Konfigurationen für den Transport von Gütern und für Spezialanwendungen genutzt. Das sichere Navigieren solcher Großfahrzeuge stellt eine herausfordernde Aufgabe für den Fahrer und unter Umständen für automatische Steuerungssysteme, z. B. im semi-autonomen oder autonomen Betrieb, dar. Insbesondere in kinematisch schwierigen Situationen, auf unebenem Untergrund oder bei engen Platzverhältnissen steigt die Komplexität des sicheren Steuerns.
Umso verwunderlicher ist es, dass unterstützende Systeme, welche die speziellen Belange von LKW und insbesondere LKW-Gespannen adressieren, im Vergleich zum Angebot auf dem PKW-Markt nur in rudimentärem Maß angeboten werden. Das Gefahrenpotential, dass von Großfahrzeugen ausgeht, wird zunehmend in der aktuellen Tagespolitik diskutiert. Unter anderem wird die verpflichtende Einführung von Fahrerassistenzsystemen gefordert.
In dieser Arbeit werden zwei Themen behandelt, die sich mit den speziellen Anforderungen von Nutzfahrzeugen befassen. Im ersten Themenblock wird die Erfassung der Artikulation in einem LKW-Anhänger-Gespann mit Drehschemelanhänger bearbeitet. Dabei wird ein neuartiges Verfahren vorgestellt, das auf an der Universität Koblenz-Landau geleisteten Vorarbeiten aufbaut. Es ermöglicht die Erfassung von Knickwinkeln in mehreren Dimensionen und ist daher auch für den Einsatz auf unebenem Grund, wie beispielsweise in Baustellen- oder Agrarszenarien geeignet. Das Verfahren nutzt dabei eine Kamera und ein künstliches Muster, um den Gespannzustand zu ermitteln.
Im zweiten Bereich wird die Umfeldvisualisierung durch eine Vogelperspektivenansicht thematisiert. Herkömmliche Systeme weisen systembedingte Verzerrungen auf, die unnatürlich wirkende Ansichten zur Folge haben. Diesem Problem wird durch die Entwicklung einer neuen Herangehensweise begegnet: Mit den Tiefendaten von Stereokameras wird eine Umgebungsmodellierung realisiert, die im nächsten Schritt perspektivisch korrekt mit Kamerabildern fusioniert wird. Mittels einer speziell für diesen Fall erweiterten Stereo-Hinderniserkennung wird zudem eine zusätzliche Umfeldüberwachung ermöglicht.
Die beiden in dieser Dissertation vorgestellten Verfahren beinhalten grundlegende Arbeiten, die für die Entwicklung maßgeschneiderter Assistenzsysteme für LKW angewandt werden können.
Die Biopolyester Cutin und Suberin stellen hydrophobe Grenzbarrieren dar, die sich im Laufe der Evolution der Landpflanzen entwickelt haben. Cutin bildet den Hauptbestandteil der Cuticula, die den Pflanzen Schutz vor unkontrollierter Transpiration bietet. Die Einlagerung von Suberin in die Zellwände definierter Zellen des Wurzelgewebes ermöglicht eine kontrollierte Aufnahme von Wasser und Nährstoffen. Zu den wichtigsten monomeren Bestandteilen dieser biologischen Polyester gehören langkettige α,ω-Dicarbonsäuren und ω-Hydroxycarbonsäuren. Bisher wurde der mikrobielle Abbau der Makromoleküle unzureichend erforscht. Zur Entschlüsselung der Zersetzung ist es notwendig, den Kreislauf der monomeren Bestandteile im Boden zu betrachten. Hierzu eignen sich vor allem Experimente mit positionsspezifisch ¹³C -markierten α,ω-Dicarbonsäuren und ω-Hydroxycarbonsäuren, die in der vorliegenden Arbeit erstmals synthetisch zugänglich gemacht wurden. Die Synthesen umfassten Dicarbonsäuren der geradzahligen Kettenlängen C12 bis C30, deren Carboxygruppen ¹³C -markiert sind. Ebenfalls wurde die Synthese von ω-Hydroxycarbonsäuren der Kettenlängen C14, C18, C22 und C30 mit ¹³C-Markierung an der Carboxygruppe realisiert. Weitere Zielverbindungen waren ω-Hydroxycarbonsäuren der Kettenlängen C14, C15, C18, C22 und C30, deren terminales hydroxyliertes Kohlenstoffatom mit ¹³C markiert ist. Im Rahmen der durchgeführten Arbeit gelang es, alle 19 Zielcarbonsäuren erfolgreich in hohen Ausbeuten und Reinheiten darzustellen. Die Synthese der isotopenmarkierten Verbindungen erforderte die Entwicklung spezieller auf die jeweiligen Zielsubstanzen individuell angepasster Syntheserouten, die den Einbau des Kohlenstoffisotops ¹³C ermöglichten. Für alle Zielverbindungen erfolgte die Einführung des ¹³C durch die Verwendung von ¹³C -markiertem Kaliumcyanid (99 at%). Wegen der hohen Kosten des ¹³C -markierten Ausgangsstoffes wurden alle Reaktionen zunächst unter der Verwendung analoger unmarkierter Edukte optimiert. Der letzte Teil der Arbeit bestand in der Ausführung eines Inkubationsexperimentes mit den ¹³C -markierten α,ω-Dicarbonsäuren der Kettenlängen C12, C18, C22 und C30. Mittels Phospholipidfettsäure-Analyse konnte gezeigt werden, dass die ¹³C -Dicarbonsäuren zu unterschiedlichen Anteilen von verschiedenen Mikroorganismengruppen zum Aufbau von Phospholipidfettsäuren verwendet wurden. Außerdem konnte durch die Anreicherung des CO2 mit dem Isotop ¹³C nachgewiesen werden, dass die ¹³C -markierten Fettsäuren von den Mikroorganismen zur Energiegewinnung abgebaut wurden. Für zukünftige Arbeiten wäre es interessant, Ausschnitte der Cutin- und Suberinstruktur nachzubilden. Durch die Veresterung der ¹³C -markierten α,ω-Dicarbonsäuren und der ¹³C -markierten ω-Hydroxycarbonsäuren untereinander oder mit Alkoholen könnten Dimere und Oligomere hergestellt werden.
Because silver nanoparticles (Ag NPs) are broadly applied in consumer products, their leaching will result in the continuous release of Ag NPs into the natural aquatic environment. Therefore, bacterial biofilms, as the prominent life form of microorganisms in the aquatic environment, are most likely confronted with Ag NPs as a pollutant stressor. Notwithstanding the significant ecological relevance of bacterial biofilms in aquatic systems, and though Ag NPs are expected to accumulate within these biofilms in the environment, the knowledge on the environmental and ecological impact of Ag NPs, is still lagging behind the industrial growth of nanotechnology. Consequently, aim of this thesis was to perform effect assessment of Ag NP exposure on bacterial biofilms with ambient Ag NPs concentrations and under environmentally relevant conditions. Therefore, a comprehensive set of methods was applied in this work to study if and how Ag NPs of two different sizes (30 and 70 nm) affect bacterial biofilms i.e. both monospecies biofilms and freshwater biofilms in environmentally relevant concentrations (600 - 2400 µg l-1). Within the first part of this work, a newly developed assay to test the mechanical stability of
monospecies biofilms of the freshwater model bacterium Aquabacterium citratiphilum was validated. In the first study, to investigate the impact of Ag NPs on the mechanical stability of bacterial biofilms, sublethal effects on the mechanical stability of the biofilms were observed with negative implications for biostabilization. Furthermore, as it is still challenging to monitor the ecotoxicity of Ag NPs in natural freshwater environments, a mesocosm study was performed in this work to provide the possibility for the detailed investigation of effects of Ag NPs on freshwater biofilms under realistic environmental conditions. By applying several approaches to analyze biofilms as a whole in response to Ag NP treatment, insights into the resilience of bacterial freshwater biofilms were obtained. However, as revealed by t-RFLP fingerprinting combined with phylogenetic studies based on the 16S gene, a shift in the bacterial community composition, where Ag NP-sensitive bacteria were replaced by more Ag NP-tolerant species with enhanced adaptability towards Ag NP stress was determined. This shift within the bacterial community may be associated with potential detrimental effects on the functioning of these biofilms with respect to nutrient loads, transformation and/or degradation of pollutants, and biostabilization. Overall, bringing together the key findings of this thesis, 4 general effect mechanisms of Ag NP treatment have been identified, which can be extrapolated to natural freshwater biofilms i.e. (i) the identification of Comamonadaceae as Ag NP-tolerant, (ii) a particular resilient behaviour of the biofilms, (iii) the two applied size fractions of Ag NPs exhibited similar effects independent of their sizes and their synthesis method, and (iv) bacterial biofilms show a high uptake capacity for Ag NPs, which indicates cumulative enrichment.
Bio-medical data comes in various shapes and with different representations.
Domain experts use such data for analysis or diagnosis,
during research or clinical applications. As the opportunities to obtain
or to simulate bio-medical data become more complex and productive,
the experts face the problem of data overflow. Providing a
reduced, uncluttered representation of data, that maintains the data’s
features of interest falls into the area of Data Abstraction. Via abstraction,
undesired features are filtered out to give space - concerning the
cognitive and visual load of the viewer - to more interesting features,
which are therefore accentuated. To address this challenge, the dissertation
at hand will investigate methods that deal with Data Abstraction
in the fields of liver vasculature, molecular and cardiac visualization.
Advanced visualization techniques will be applied for this purpose.
This usually requires some pre-processing of the data, which will also
be covered by this work. Data Abstraction itself can be implemented
in various ways. The morphology of a surface may be maintained,
while abstracting its visual cues. Alternatively, the morphology may
be changed to a more comprehensive and tangible representation.
Further, spatial or temporal dimensions of a complex data set may
be projected to a lower space in order to facilitate processing of the
data. This thesis will tackle these challenges and therefore provide an
overview of Data Abstraction in the bio-medical field, and associated
challenges, opportunities and solutions.
The analysis of three-dimensional and complex motion sequences
of human gait and therefore the most important question
of kenesiology ”why are we falling?” is the essence of this
paper. The gerontology and its science of movement is currently
limited to simple and one-dimensional methods and models. An
extensive literature research shows the latest state of research of
the three common methods to determine the stability of human
gait. To assess the margin of stability, local stability and orbital
stability it is shown, how those methods are applicable to evaluate
the subject’s ability to recover from any disturbences of
the subject’s gait. Based on this assessment and the method’s
advantages and disadvantages a new method will be derived
that allows spatial analysis of dynamic instability of linear and
non-linear human gait. A motion capture system and the timed
up and go test serve as a basis for this new method and will be
explained. A numerical approximation to optimise the number
of markers within a marker-set of a motion capture analysis
and its maximum correlation with the full-body-marker-set will
be given. This simplification is very helpful for further clinical
or scientific research. To validate the new method a trial
with subjects will be shown and discussed. New appreciable
variables and snapshots of specific situations during the gait
offer new and different interpretations of the human gait. The
new method is the most applicable and appropriate assessment
of human gait and the individual development of the human
gait while aging, as well as to detect and prevent falling and
associated injuries. Especially directional change of a non-linear
gait become assessable with the new method.
The increase in plastic particles (< 5 mm) in the environment is a global problem, which is in direct correlation to the increasing production quantity and variety. Through direct input (primary) or through the degradation of macroplastics (secondary), particles enter the environmental compartments water and/or soil via conventional material transportation paths. The research and development work on the sustainable removal of microplastic particles (inert organic chemical stressors, IOCS) from wastewater is based on the construction of polymer inclusion compounds. IOCS describe a group of organic chemical molecules, which demonstrate a high level of persistence upon entry in the ecosystem and whose degradation is limited.
Following the principle of Cloud Point Technology, a novel separation technique has been developed which induces particle growth in microplastics and allows easier separation from the water by volume increase according to the state of the art. The concept for the sustainable removal of microplastics from Herbort and Schuhen is based on a three-step synthesis. This concept was further optimized as part of the research and adapted to the criteria of resource efficiency and profitability. The fundamental research is premised on the hypothesis that van der Waals forces with short ranges and localized hydrophobic interactions between precursors and/or material and the IOCS to be connected can induce a fixation through the formation of an inclusion compound with particle growth. Through the addition of silicon-based ecotoxicologically irrelevant coagulation and inclusion units, it is possible to initiate molecular self-organization with the hydrophobic stressors in an aggregation process induced through water. It results in adhesive particle growth around the polymer particles and between particles. Subsequently, the polymer extract can be separated from aquatic media through simple and cost-effective filtration processes (e.g. sand trap, grease trap), due to the 10,000 times larger volume microplastic agglomerates.
The European landscape is dominated by intensive agriculture which leads to widespread impact on the environment. The frequent use of agricultural pesticides is one of the major causes of an ongoing decline in flower-visiting insects (FVIs). The conservation of this ecologically diverse assemblage of mobile, flying insect species is required by international and European policy. To counteract the decrease in species numbers and their abundances, FVIs need to be protected from anthropogenic stressors. European pesticide risk assessment was devised to prevent unacceptable adverse consequences of pesticide use on FVIs. However, there is an ongoing discussion by scientists and policy-makers if the current risk assessment actually provides adequate protection for FVI species.
The first main objective of this thesis was to investigate pesticide impact on FVI species. The scientific literature was reviewed to identify groups of FVIs, summarize their ecology, and determine their habitat. This was followed by a synthesis of studies about the exposure of FVIs in their habitat and subsequent effects. In addition, the acute sensitivity of one FVI group, bee species, to pesticides was studied in laboratory experiments.
The second main objective was to evaluate the European risk assessment for possible deficits and propose improvements to the current framework. Regulatory documents were screened to assess the adequacy of the guidance in place in light of the scientific evidence. The suitability of the honey bee Apis mellifera as the currently only regulatory surrogate species for FVIs was discussed in detail.
The available scientific data show that there are far more groups of FVIs than the usually mentioned bees and butterflies. FVIs include many groups of ecologically different species that live in the entire agricultural landscape. Their habitats in crops and adjacent semi-natural areas can be contaminated by pesticides through multiple pathways. Environmentally realistic exposure of these habitats can lead to severe effects on FVI population parameters. The laboratory studies of acute sensitivity in bee species showed that pesticide effects on FVIs can vary greatly between species and pesticides.
The follow-up critical evaluation of the European FVI risk assessment revealed major shortcomings in exposure and effect assessment. The honey bee proved to be a sufficient surrogate for bee species in lower tier risk assessment. Additional test species may be chosen for higher tier risk assessment to account for ecological differences. This thesis shows that the ecology of FVIs should generally be considered to a greater extent to improve the regulatory process. Data-driven computational approaches could be used as alternative methods to incorporate ecological trait data in spatio-temporal scenarios. Many open questions need to be answered by further research to better understand FVI species and promote necessary changes to risk assessment. In general, other FVI groups than bees need to be investigated. Furthermore, comprehensive data on FVI groups and their ecology need to be collected. Contamination of FVI habitat needs to be linked to exposure of FVI individuals and ecologically complex effects on FVI populations should receive increased attention. In the long term, European FVI risk assessment would benefit from shifting its general principles towards more scientifically informed regulatory decisions. This would require a paradigm shift from arbitrary assumptions and unnecessarily complicated schemes to a substantiated holistic framework.
Die Entwicklung von naturwissenschaftlichen Konzepten und Bildungssprache beginnt schon vor dem Schuleintritt und bildungssprachliche und naturwissenschaftliche Kompetenzen werden als wichtige Faktoren für Schulerfolg angesehen (Ehlich, Bredel & Reich, 2008; Saçkes, Trundle & Bell, 2013). Die frühe Förderung dieser Kompetenzen ist deshalb sinnvoll.
Lernumgebungen, die naturwissenschaftliche Konzepte fördern (Hardy, Möller & Stern, 2006; Leuchter, Saalbach & Hardy, 2014), zeichnen sich ebenso wie Lernumgebungen, die Bildungssprache fördern (Gibbons, 2006; Quehl & Trapp, 2013), dadurch aus, dass sie zum Sammeln eigener Erfahrungen (z.B. beim Experimentieren) und zum Versprachlichen und Begründen eigener Gedanken anregen (z.B. in Planungs- und Reflexionsphasen). Die zur Förderung von Bildungssprache erforderliche sprachliche Komplexität wird besonders in Gesprächen herausgefordert, die außerhalb der Experimentiersituation, d.h. kontext-reduziert, stattfinden (Gibbons, 2006; Quehl & Trapp, 2013). Bisherige Forschung untersucht allerdings entweder sprachliche oder konzeptuelle Fortschritte und dies überwiegend im schulischen Kontext. Eine gemeinsame Betrachtung beider Bereiche bei Vorschulkindern fehlt bisher. Die zentrale Forschungsfrage der Arbeit lautet daher: „Welche Effekte haben kontext-reduzierte Gespräche auf Vorstellungen von Vorschulkindern zu zweiseitigen Hebeln und deren bildungssprachliche Lexik und Grammatik?“
Die Effekte kontext-reduzierter Gespräche wurden in einem quasi-experimentellen Design (N = 90) mit drei Gruppen untersucht. Alle Gruppen nahmen an Experimentierphasen zu zweiseitigen Hebeln teil. Zwei Gruppen erhielten außerdem Planungs- und Reflexionsphasen mit verbalen Unterstützungsmaßnahmen. In der kontext-reduzierten Bedingung fanden die Planungs- und Reflexionsgespräche in raum-zeitlicher Trennung zum Experimentiermaterial statt, in der kontextualisierten Bedingung stand den Kindern das Material auch während der Planungs- und Reflexionsphasen zur Verfügung.
Zwischen kontext-reduzierten und kontextualisierten Gesprächen konnten weder signifikante Unterschiede im naturwissenschaftlichen Konzept noch in den bildungssprachlichen Kompetenzen gefunden werden. Ein signifikanter Fördereffekt von Planungs- und Reflexionsgesprächen gegenüber der reinen Experimentierphase ohne Gespräche zeigt sich für konzeptuelle Vorstellungen zu zweiseitigen Hebeln, jedoch nicht für bildungssprachliche Lexik und Grammatik. Diese Ergebnisse lassen sich aus dem theoretischen Hintergrund nur bedingt erklären und geben Anlass für weitere Forschung.
Environmental processes transforming inorganic nanoparticles: implications on aquatic invertebrates
(2020)
Engineered inorganic nanoparticles (EINPs) are produced and utilized on a large scale and will end up in surface waters. Once in surface waters, EINPs are subjected to transformations induced by environmental processes altering the particles’ fate and inherent toxicity. UV irradiation of photoactive EINPs is defined as one effect-inducing pathway, leading to the formation of reactive oxygen species (ROS), increasing EINP toxicity by exerting oxidative stress in aquatic life. Simultaneously, UV irradiation of photoactive EINP alters the toxicity of co-occurring micropollutants (e.g. pesticides) by affecting their degradation. The presence of natural organic matter (NOM) reduces the agglomeration and sedimentation of EINPs, extending the exposure of pelagic species, while delaying the exposure of benthic species living in and on the sediment, which is suggested as final sink for EINPs. However, the joint impact of NOM and UV irradiation on EINP-induced toxicity, but also EINP-induced degradation of micropollutants, and the resulting risk for aquatic biota, is poorly understood. Although potential effects of EINPs on benthic species are increasingly investigated, the importance of exposure pathways (waterborne or dietary) is unclear, along with the reciprocal pathway of EINPs, i.e. the transport back from aquatic to terrestrial ecosystems. Therefore, this thesis investigates: (i) how the presence of NOM affects the UV-induced toxicity of the model EINP titanium dioxide (nTiO2) on the pelagic organism Daphnia magna, (ii) to which extent UV irradiation of nTiO2 in the presence and absence of NOM modifies the toxicity of six selected pesticides in D. magna, (iii) potential exposure pathway dependent effects of nTiO2 and silver (nAg) EINPs on the benthic organism Gammarus fossarum, and (iv) the transport of nTiO2 and gold EINPs (nAu) via the merolimnic aquatic insect Chaetopteryx villosa back to terrestrial ecosystems. nTiO2 toxicity in D. magna increased up to 280-fold in the presence of UV light, and was mitigated by NOM up to 12-fold. Depending on the pesticide, UV irradiation of nTiO2 reduced but also enhanced pesticide toxicity, by (i) more efficient pesticide degradation, and presumably (ii) formation of toxic by-products, respectively. Likewise, NOM reduced and increased pesticide toxicity, induced by (i) protection of D. magna against locally acting ROS, and (ii) mitigation of pesticide degradation, respectively. Gammarus’ energy assimilation was significantly affected by both EINPs, however, with distinct variation in direction and pathway dependence between nTiO2 and nAg. EINP presence delayed C. villosa emergence by up to 30 days, and revealed up to 40% reduced lipid reserves, while the organisms carried substantial amounts of nAu (~1.5 ng/mg), and nTiO2 (up to 2.7 ng/mg). This thesis shows, that moving test conditions of EINPs towards a more field-relevant approach, meaningfully modifies the risk of EINPs for aquatic organisms. Thereby, more efforts need to be made to understand the relative importance of EINP exposure pathways, especially since a transferability between different types of EINPs may not be given. When considering typically applied risk assessment factors, adverse effects on aquatic systems might already be expected at currently predicted environmental EINP concentrations in the low ng-µg/L range.
The distributed setting of RDF stores in the cloud poses many challenges. One such challenge is how the data placement on the compute nodes can be optimized to improve the query performance. To address this challenge, several evaluations in the literature have investigated the effects of existing data placement strategies on the query performance. A common drawback in theses evaluations is that it is unclear whether the observed behaviors were caused by the data placement strategies (if different RDF stores were evaluated as a whole) or reflect the behavior in distributed RDF stores (if cloud processing frameworks like Hadoop MapReduce are used for the evaluation). To overcome these limitations, this thesis develops a novel benchmarking methodology for data placement strategies that uses a data-placement-strategy-independent distributed RDF store to analyze the effect of the data placement strategies on query performance.
With this evaluation methodology the frequently used data placement strategies have been evaluated. This evaluation challenged the commonly held belief that data placement strategies that emphasize local computation, such as minimal edge-cut cover, lead to faster query executions. The results indicate that queries with a high workload may be executed faster on hash-based data placement strategies than on, e.g., minimal edge-cut covers. The analysis of the additional measurements indicates that vertical parallelization (i.e., a well-distributed workload) may be more important than horizontal containment (i.e., minimal data transport) for efficient query processing.
Moreover, to find a data placement strategy with a high vertical parallelization, the thesis tests the hypothesis that collocating small connected triple sets on the same compute node while balancing the amount of triples stored on the different compute nodes leads to a high vertical parallelization. Specifically, the thesis proposes two such data placement strategies. The first strategy called overpartitioned minimal edge-cut cover was found in the literature and the second strategy is the newly developed molecule hash cover. The evaluation revealed a balanced query workload and a high horizontal containment, which lead to a high vertical parallelization. As a result these strategies showed a better query performance than the frequently used data placement strategies.
Nowadays, almost any IT system involves personal data processing. In
such systems, many privacy risks arise when privacy concerns are not
properly addressed from the early phases of the system design. The
General Data Protection Regulation (GDPR) prescribes the Privacy by
Design (PbD) principle. As its core, PbD obliges protecting personal
data from the onset of the system development, by effectively
integrating appropriate privacy controls into the design. To
operationalize the concept of PbD, a set of challenges emerges: First, we need a basis to define privacy concerns. Without such a basis, we are not able to verify whether personal data processing is authorized. Second, we need to identify where precisely in a system, the controls have to be applied. This calls for system analysis concerning privacy concerns. Third, with a view to selecting and integrating appropriate controls, based on the results of system analysis, a mechanism to identify the privacy risks is required. Mitigating privacy risks is at the core of the PbD principle. Fourth, choosing and integrating appropriate controls into a system are complex tasks that besides risks, have to consider potential interrelations among privacy controls and the costs of the controls.
This thesis introduces a model-based privacy by design methodology to handle the above challenges. Our methodology relies on a precise definition of privacy concerns and comprises three sub-methodologies: model-based privacy analysis, modelbased privacy impact assessment and privacy-enhanced system design modeling. First, we introduce a definition of privacy preferences, which provides a basis to specify privacy concerns and to verify whether personal data processing is authorized. Second, we present a model-based methodology to analyze a system model. The results of this analysis denote a set of privacy design violations. Third, taking into account the results of privacy analysis, we introduce a model-based privacy impact assessment methodology to identify concrete privacy risks in a system model. Fourth, concerning the risks, and taking into account the interrelations and the costs of the controls, we propose a methodology to select appropriate controls and integrate them into a system design. Using various practical case studies, we evaluate our concepts, showing a promising outlook on the applicability of our methodology in real-world settings.
Gel effect induced by mucilage in the pore space and consequences on soil physical properties
(2020)
Water uptake, respiration and exudation are some of the biological functions fulfilled by plant roots. They drive plant growth and alter the biogeochemical parameters of soil in the vicinity of roots, the rhizosphere. As a result, soil processes such as water fluxes, carbon and nitrogen exchanges or microbial activity are enhanced in the rhizosphere in comparison to the bulk soil. In particularly, the exudation of mucilage as a gel-like substance by plant roots seems to be a strategy for plants to overcome drought stress by increasing soil water content and soil unsaturated hydraulic conductivity at negative water potentials. Although the variations of soil properties due to mucilage are increasingly understood, a comprehensive understanding of the mechanisms in the pore space leading to such variations is lacking.
The aim of this work was to elucidate the gel properties of mucilage in the pore space, i.e. interparticulate mucilage, in order to link changes of the physico-chemical properties in the rhizosphere to mucilage. The fulfilment of this goal was confronted to the three following challenges: The lack of methods for in situ detection of mucilage in soil; The lack of knowledge concerning the properties of interparticulate mucilage; The unknown relationship between the composition and the properties of model substances and root mucilage produced by various species. These challenges are addressed in several chapters.
In a first instance, a literature review picked information from various scientific fields about methods enabling the characterization of gels and gel phases in soil. The variation of soil properties resulting from biohydrogel swelling in soil was named the gel effect. The combined study of water entrapment of gels and gel phases in soil and soil structural properties in terms of mechanical stability or visual structures proved promising to disentangle the gel effect in soil.
The acquired methodical knowledge was used in the next experiments to detect and characterize the properties of interparticulate gel. 1H NMR relaxometry allows the non-invasive measure of water mobility in porous media. A conceptual model based on the equations describing the relaxation of water protons in porous media was developed to integrate the several gel effects into the NMR parameters and quantify the influence of mucilage on proton relaxation. Rheometry was additionally used to assess mucilage viscosity and soil microstructural stability and ESEM images to visualize the network of interparticulate gel. Combination of the results enabled to identify three main interparticulate gel properties: The spider-web effect restricts the elongation of the polymer chains due to the grip of the polymer network to the surface of soil particles. The polymer network effect illustrates the organization of the polymer network in the pore space according to the environment. The microviscosity effect describes the increased viscosity of interparticulate gel in contrast to free gel. The impact of these properties on soil water mobility and microstructural stability were investigated. Consequences on soil hydraulic and soil mechanical properties found in the literature are further discussed.
The influence of the chemical properties of polymers on gel formation mechanism and gel properties was also investigated. For this, model substances with various uronic acid content, degree of esterification and amount of calcium were tested and their amount of high molecular weight substances was measured. The substances investigated included pectic polysaccharides and chia seed mucilage as model polymers and wheat and maize root mucilage. Polygalacturonic acid and low-methoxy pectin proved as non-suitable model polymers for seed and root mucilage as ionic interactions with calcium control their properties. Mucilage properties rather seem to be governed by weak electrostatic interactions between the entangled polymer chains. The amount of high molecular weight material varies considerably depending on mucilage´s origin and seems to be a straight factor for mucilage’s gel effect in soil. Additionally to the chemical characterization of the high molecular weight compounds, determination of their molecular weight and of their conformation in several mucilages types is needed to draw composition-property profiles. The variations measured between the various mucilages also highlight the necessity to study how the specific properties of the various mucilages fulfill the needs of the plant from which they are exuded.
Finally, the integration of molecular interactions in gel and interparticulate gel properties to explain the physical properties of the rhizosphere was discussed. This approach offers numerous perspectives to clarify for example how water content or hydraulic conductivity in the rhizosphere vary according to the properties of the exuded mucilage. The hypothesis that the gel effect is general for all soil-born exudates showing gel properties was considered. As a result, a classification of soil-born gel phases including roots, seeds, bacteria, hyphae and earthworm’s exuded gel-like material according to their common gel physico-chemical properties is recommended for future research. An outcome could be that the physico-chemical properties of such gels are linked with the extent of the gel effect, with their impact on soil properties and with the functions of the gels in soil.
The bio-insecticide Bacillus thuringiensis israelensis (Bti) has worldwide become the most commonly used agentin mosquito control programs that pursue two main objectives: the control of vector-borne diseases and the reduction of nuisance, mainly coming frommosquitoes that emerge in large quantities from seasonal wetlands. The Upper Rhine Valley, a biodiversity hotspot in Germany, has been treated withBti for decades to reduce mosquito-borne nuisance and increase human well-being.Although Btiis presumed to be an environmentally safe agent,adverse effects on wetland ecosystems are still a matter of debate especially when it comes to long-term and indirect effects on non-target organisms. In light of the above, this thesis aims at investigating direct and indirect effects of Bti-based mosquito control on non-target organisms within wetland food chains.Effects were examinedin studies with increasingeco(toxico)logical complexity, ranging from laboratory over mesocosm to field approaches with a focus on the non-biting Chironomidae and amphibian larvae (Rana temporaria, Lissotriton sp.).In addition, public acceptance of environmentally less invasive alternative mosquito control methods was evaluated within surveys among the local population.
Chironomids were the most severely affected non-target aquatic invertebrates. Bti substantially reduced larval and adult chironomid abundances and modified their species composition. Repeated exposures to commonly used Bti formulations induced sublethal alterations of enzymatic biomarkers activityin frog tadpoles. Bti-induced reductions of chironomid prey availability indirectly decreased body size of newts at metamorphosis and increased predation on newt larvae in mesocosm experiments. Indirect effects of severe reductions in midge biomassmight equally be passed through aquatic but also terrestrial food chains influencing predators of higher trophic levels. The majority ofaffectedpeople in the Upper Rhine Valley expressed a high willingness to contributefinancially to environmentally less harmful mosquito control.Alternative approaches could still include Bti applications excepting treatment of ecologically valuable areas. Potentially rising mosquito levels could be counteracted with local acting mosquito traps in domestic and urban areas because mosquito presence was experienced as most annoying in the home environment.
As Bti-based mosquito control can adversely affect wetland ecosystems, its large-scale applications, including nature conservation areas, should be considered more carefully to avoid harmful consequences for the environmentat the Upper Rhine Valley.This thesis emphasizesthe importance to reconsiderthe current practice of mosquito control and encourage research on alternative mosquito control concepts that are endorsed by the local population. In the context ofthe ongoing amphibian and insect declinesfurther human-induced effects onwetlands should be avoided to preserve biodiversity in functioning ecosystems.
Die vorliegende Dissertation beschäftigt sich mit euroskeptischen Äußerungen in der Parteienkommunikation und der Medienberichterstattung im Vorfeld der Europawahl 2014. Die Arbeit verwendet ein akteurszentriertes Forschungsdesign, welches eine differenzierte Betrachtung der öffentlichen Debatte europäischer Themen erlaubt. Die Analyse deckt auf, welche nationalen Parteien euroskeptische Positionen vertreten und inwiefern diese Einzug in die mediale Berichterstattung finden. Auch die Positionierung der Medien selbst wird durch die Untersuchung meinungsbezogener Artikel berücksichtigt. Die den Studien zu Grunde liegende Konzeptualisierung des Euroskeptizismus-Begriff umfasst neben globalen und konkreten negativen Bewertungen der EU auch die Zuschreibung von Problemverantwortung als weitere Spielart euroskeptischer Äußerungen. Die Arbeit nimmt weiterhin eine international vergleichende Perspektive ein, um den Einfluss nationaler Kontextfaktoren auf die Verbreitung euroskeptischer Positionen aufzuzeigen.
Die Ergebnisse der Analyse decken zunächst auf, dass das Vorhandensein erstarkender euroskeptischer Oppositionsparteien nicht zwangsläufig zu einer Politisierung der europäischen Debatte führt, da sich die europhilen Mainstream-Parteien verschiedener Strategien zur Vermeidung einer solchen Kontroversen bedienen. Die Analysen ergeben weiterhin, dass europhile Regierungsparteien zwar mehrheitlich vor konkreten negativen Bewertungen der EU zurückschrecken, diese aber in Bezug auf die europäische Finanzkrise vorwiegend als Verursacher von Problemlagen skizzieren. Letztlich verdeutlichen die Ergebnisse, dass die mediale Berichterstattung zu Themen mit EU-Bezug eine starke Synchronizität zwischen Nachrichten- und Meinungsteil aufzeigt. Dies gilt sowohl in Bezug auf die geäußerten Bewertungen zur Europäischen Union als auch hinsichtlich der Darstellung von Verantwortlichkeit.
In der vorliegenden Studie geht es um den möglichen und tatsächlichen Beitrag von sogenannten Geschäftsmodellen im Kontext eines reflexiven Bildungsmanagements im Feld der wissenschaftlichen Weiterbildung an (öffentlichen) Hochschulen in Deutschland.
Im Anschluss an Behrmann (2006) wird ein reflexives Bildungsmanagement verwendet, um mögliche strategische und entwicklungsrelevante Orientierungen für die strategische (Neu-)Positionierung von Weiterbildungseinrichtungen bzw. reflexive Entwicklung von Hochschulen im Handlungs- bzw. Geschäftsfeld der wissenschaftlichen Weiterbildung zu strukturieren. In diesem Zusammenhang unterstützen Geschäftsmodelle die Realisierung des (Weiter-)Bildungsauftrags von (öffentlichen) Hochschulen bzw. von deren Weiterbildungseinrichtungen. Diese möglichen Orientierungen wurden im Rahmen von qualitativen Inhaltsanalysen nach Kuckartz (2016) auf der Grundlage von visualisierten Gruppendiskussionen nach Kühl (2009) rekonstruiert. Der Feldzugang erfolgte mit Unterstützung der Deutschen Gesellschaft für wissenschaftliche Weiterbildung und Fernstudium e.V. (DGWF).
Absicherung der analytischen Interpretation von Geolokalisierungsdaten in der Mobilfunkforensik
(2019)
Abstract
Location based services maybe are within one of the most outstanding features of modern mobile devices. Despite the fact, that cached geolocation data could be used to reconstruct motion profiles, the amount of devices capable to provide these information in the field of criminal investigations is growing.
Motivation
The aim of this work is to generate in-depth knowledge to questions concerning geolocation in the field of mobile forensics, making especially somehow cached geolocation data forensically valuable. On top, tools meeting the specific requirements of law enforcement personnel shall be developed.
Problems
Geolocation processes within smartphones are quite complex. For the device to locate its position, different reference systems like GPS, cell towers or WiFi hot\-spots are used in a variety of ways. The whole mobile geolocation mechanism is proprietary to the device manufacturer and not build with forensic needs in mind. One major problem regarding forensic investigations is, that mainly reference points are being extracted and processed instead of real life device location data. In addition, these geolocation information only consist of bits and bytes or numeric values that have to be securely assigned to their intended meaning. The location data recovered are full of gaps providing only a part of the process or device usage. This possible loss of data has to be determined deriving a reliable measurement for the completeness, integrity and accuracy of data. Last but not least, as for every evidence within a criminal investigation, it has to be assured, that manipulations of the data or errors in position estimation have no disadvantageous effect on the analysis.
Research Questions
In the context of localisation services in modern smartphones, it always comes back to similar questions during forensic everyday life:
* Can locations be determined at any time?
* How accurate is the location of a smartphone?
* Can location data from smartphones endure in court?
Approach
For a better understanding of geolocation processes in modern smartphones and to evaluate the quality and reliability of the geolocation artefacts, information from different platforms shall be theoretically analysed as well as observed in-place during the geolocation process. The connection between data points and localisation context will be examined in predefined live experiments as well as desktop- and native applications on smartphones.
Results
Within the scope of this thesis self developed tools have been used for forensic investigations as well as analytical interpretation of geodata from modern smartphones. Hereby a generic model for assessing the quality of location data has emerged, which can be generally applied to geodata from mobile devices.
This dissertation deals with the opportunities and restrictions that parties face in an election campaign at the supranational level of the EU. Using communication science concepts of agenda-setting (focus: media) and agenda-building (focus: political parties), the first part of the study is based on the election campaign for the European Parliament (EP) in 2014. It analyses to what extent political parties put the EU on the agenda. Second, it is examined whether parties have used their structural advantage of being able to influence the media agenda at the supranational level during the election campaign in the context of the EP election campaign. Third, it is examined whether parties can gain an advantage for the visibility of their campaigns by rejecting EU integration and the associated conflictual communication. Fourth and final, it will be explored whether agenda-building can influence the rankings of specific policy issues on the media agenda in the European context.
First, the analyses show that a European political focus of election campaign communication can no longer be found only on the part of the small (eurosceptic) parties. Second, parties have a good chance of being present in media coverage if the they pursue a European political focus in their campaign communication. Third, a negative tone in party communication turns out not to be decisive for the parties' visibility in the election campaign. Fourth, a clear positioning on political issues also prepares parties for restrictions of the further development of a European thematic agenda. After a discussion of these results, the paper concludes with an assessment of the analysis limitations and an outlook on further research approaches.
Software systems have an increasing impact on our daily lives. Many systems process sensitive data or control critical infrastructure. Providing secure software is therefore inevitable. Such systems are rarely being renewed regularly due to the high costs and effort. Oftentimes, systems that were planned and implemented to be secure, become insecure because their context evolves. These systems are connected to the Internet and therefore also constantly subject to new types of attacks. The security requirements of these systems remain unchanged, while, for example, discovery of a vulnerability of an encryption algorithm previously assumed to be secure requires a change of the system design. Some security requirements cannot be checked by the system’s design but only at run time. Furthermore, the sudden discovery of a security violation requires an immediate reaction to prevent a system shutdown. Knowledge regarding security best practices, attacks, and mitigations is generally available, yet rarely integrated part of software development or covering evolution.
This thesis examines how the security of long-living software systems can be preserved taking into account the influence of context evolutions. The goal of the proposed approach, S²EC²O, is to recover the security of model-based software systems using co-evolution.
An ontology-based knowledge base is introduced, capable of managing common, as well as system-specific knowledge relevant to security. A transformation achieves the connection of the knowledge base to the UML system model. By using semantic differences, knowledge inference, and the detection of inconsistencies in the knowledge base, context knowledge evolutions are detected.
A catalog containing rules to manage and recover security requirements uses detected context evolutions to propose potential co-evolutions to the system model which reestablish the compliance with security requirements.
S²EC²O uses security annotations to link models and executable code and provides support for run-time monitoring. The adaptation of running systems is being considered as is round-trip engineering, which integrates insights from the run time into the system model.
S²EC²O is amended by prototypical tool support. This tool is used to show S²EC²O’s applicability based on a case study targeting the medical information system iTrust.
This thesis at hand contributes to the development and maintenance of long-living software systems, regarding their security. The proposed approach will aid security experts: It detects security-relevant changes to the system context, determines the impact on the system’s security and facilitates co-evolutions to recover the compliance with the security requirements.
Im Zentrum der Untersuchung steht die Entwicklung des künstlerischen Siebdrucks in Deutschland seit dem Zweiten Weltkrieg. Nach der thematischen Einführung und einer ersten kritischen Bestandsaufnahme der Forschung zum Siebdruck wird im Folgenden der Verlauf und die methodische Vorgehensweise der Arbeit verdeutlicht. Im zweiten Kapitel „Etablierung einer künstlerischen Technik“ wird zuerst die Geschichte des Siebdrucks dem Rahmen dieser Arbeit gemäß nachgezeichnet. Nachfolgend wird in einem Unterkapitel dargestellt, wie sich die Serigrafie als künstlerisches Verfahren parallel zum industriellen Siebdruck etablierte. In der Folge wendet sich die Untersuchung der Entstehung und Entwicklung des künstlerischen Siebdrucks in Deutschland zu. Dabei wird Willi Baumeister als Beispiel für die erste Generation von Künstlern in Deutschland herangezogen, die sich mit der Serigrafie beschäftigte. Im nächsten Schritt wird ein Überblick zu den Willi Baumeister nachfolgenden deutschen bzw. deutschsprachigen Serigrafie–Künstlern präsentiert. In dem sich anschließenden Exkurs-Kapitel liegt der Schwerpunkt auf der Zusammenarbeit zwischen Künstler und Drucker. Dabei werden an Beispielen namhafter Drucker wie Luitpold Domberger und Hans-Peter Haas unter anderem Einflüsse der Drucker auf die Entstehung und den Ausdruck der Kunstwerke aufgezeigt.Nach einer Einführung in die Entstehung und Geschichte der Serigrafie in Deutschland und einem ersten Überblick über deutsche Serigrafie-Künstler wird im vierten Kapitel der Einsatz der Serigrafie-Technik bei verschiedenen Künstlern aus unterschiedlichen Zeiträumen eingehend untersucht. Besonderes Augenmerk gilt dabei dem Einfluss der Technik auf die Ausdrucksmöglichkeiten und Inhalte der Werke, die Anwendung innerhalb einer und verschiedener Kunstrichtungen sowie die Experimente, die mit der Siebdrucktechnik gemacht wurden. Dazu werden Werke ausgewählter Künstler analysiert. Im Fokus stehen Künstler der Pop Art, des Neuen und des Kritischen Realismus, der Abstrakten und Konkreten Kunst. Ferner werden Künstler, deren Werk durch einen expressiven, bisweilen primitiven Charakter geprägt ist, in die Betrachtung mit einbezogen. Eine weitere Gruppe bilden Künstler, die die Serigrafie in einen Zusammenhang zur Architektur und zum öffentlichen Raum stellen. Die aus der Untersuchung hervorgehenden Ergebnisse dienen insbesondere dazu, die Charakteristika der Technik in ihrer künstlerischen Verwendung herauszustellen und Aspekte einer künstlerisch motivierten Weiterentwicklung aufzuzeigen. Die Entwicklung des druckgraphischen Werkes und der Technik von Gerd Winner werden in Kapitel 5 eingehend untersucht. Auf diese Weise lässt sich eine systematische, nicht rein formale, sondern ästhetische und inhaltliche Darstellung der Serigrafie in Deutschland erstellen. Ein besonderes Augenmerk liegt dabei auf der Frage, wie sich die Technik und deren Neuerungen auf den Inhalt auswirkten.
Politische Steuerung in nationalen Bologna-Prozessen in Deutschland, Österreich und der Schweiz
(2019)
Das Ziel der Dissertation besteht in der Erklärung und Analyse grundlegender Steuerungsmuster zwischen Politik und Universitätssystem in den nationalen Bologna-Prozessen in Deutschland, Österreich und der Schweiz: Wurde die Studienreform primär staatlich verordnet, im Dialog mit den Hochschulen implementiert oder die Ausgestaltung der Reform der Wissenschaft weitgehend überlassen - und welche Instrumente wurden dabei weshalb genutzt? Damit schließt die Arbeit an den aktuellen Forschungsstand zu vertikalen Vermittlungsprozessen (übernational-national) im Bologna-Prozess an: Nationale Hochschulsysteme konvergieren nicht zu einem einheitlichen Modell, sondern nationale Faktoren (z.B. Problemdeutungen und Einflussmöglichkeiten von Bildungspolitik, Universitäten u.a.) führen dazu, dass Bologna jeweils länderspezifisch verstanden und interpretiert wird.
Vor diesem Hintergrund wird im theoretischen Teil zur Anleitung eines systematischen Vergleichs ein analytischer Rahmen entworfen, dessen Elemente sowohl aus der Politikwissenschaft (Instrumenteforschung, Politische Steuerung, Governance etc.) als auch aus der Hochschulforschung stammen. In den anschließenden empirischen Kapiteln zu den drei Ländern werden die Akteurkonstellationen und faktisch zu beobachtenden Instrumentarien beschrieben, analysiert und interpretiert. Die methodische Basis bilden neben der Analyse zahlreicher Dokumente 37 leitfadengestützte Interviews mit Expertinnen und Experten.
Grundsätzlich lassen sich auf Basis der empirischen Teile die folgenden zentralen Ergebnisse der Studie festhalten:
Deutschland: Aufgrund der relativ starken Kompetenzen der Länder und der Einflussschwäche der Universitäten ist für den deutschen Bologna-Prozess ein primär interventionistisches Muster kennzeichnend. Dieses wurde und wird bis heute dadurch verstärkt, dass die Umsetzung von Bologna durch spezifische Problemwahrnehmungen und -lösungen von KMK und HRK in den 90er Jahren geprägt ist (z.B. Modularisierung als Antwort auf unstrukturierte Studiengänge, Akkreditierung als Fortführung der tradierten Input-Steuerung). `Bologna` wurde so mit genuin nationalen Instrumenten verquickt, die z.T. quer zum tradierten Lehrhabitus vieler Hochschullehrerinnen und -lehrer lag und liegt (z.B. Modularisierung oder Kompetenzorientierung). Verstärkend trat hinzu, dass die Reform u.a. aufgrund des Bund/Länder-Konflikts in der Bildungspolitik im Vorfeld der Föderalismusreform I nicht finanziell unterstützt wurde. Plastisch formuliert ist der deutsche Bologna-Prozess regulativ über- und finanziell untersteuert, was auch zu den Studierendenprotesten 2009/2010 beitrug.
Österreich: Der Bologna-Prozess lief in Österreich parallel zu einem umfassenden Neuordnungsprozess, innerhalb dessen die Universitäten in ihrer Autonomie erheblich gestärkt wurden und sich das zuvor zentrale Wissenschaftsministerium in seinen Kompetenzen erheblich limitierte. Dieses hatte die Reform unmittelbar 1999 noch angestoßen, zog sich anschließend jedoch im Rahmen einer `minimalen Steuerung` zurück und übernahm auch keine Reformmehrkosten. Da unterhalb der in die Autonomie entlassenen Universitäten kein nationaler Dialog über die Reform in Gang kommen konnte, fand der Bologna-Prozess vor allem auf der Ebene der jeweils eigenständigen Universitäten `vor Ort` statt. Diese erhebliche regulative und finanzielle Untersteuerung führte 2009/2010 zu massiven Studierendenprotesten, die angesichts der schwachen Position des Ministeriums auch nur unzureichend kanalisiert werden konnten.
Schweiz: In der Schweiz hingegen ist eine austarierte regulative und finanzielle Steuerung zu beobachten. Bund und Kantone übertrugen Anfang der 2000er Jahre wenige, aber wesentliche Kompetenzen auf ein gemeinsames Organ, das seinerseits per Gesetz eng mit der Rektorenkonferenz zusammenarbeiten sollte. Bologna stärkte dieses bis dato auf dem Papier bestehende Muster: Vor dem Hintergrund einer übergreifend geteilten prozessualen Subsidiaritätsnorm sowie weitgehender Präferenzenübereinstimmung zwischen Politik und Universitäten finanzierte der Staat gezielt die Reformmehrkosten sowie strategische Projekte und delegiert die Formulierung, Implementierung und Weiterentwicklung zentraler Vorgaben auf der Basis des Entscheidungsvorbehalts an die Rektorenkonferenz bzw. Universitäten. Probleme werden innerhalb dieses Arrangements z.T. identifiziert und bearbeitet. Die Politik greift nur subsidiär im Ausnahmefall ein. Die Schweiz kommt daher dem Idealtypus der strukturierenden Steuerung sehr nahe.
Die Befunde werden abschließend in einen größeren Bezugsrahmen eingeordnet, um sie über Bologna hinaus für die Analyse des deutschen Hochschulsystems fruchtbar zu machen. Maßstab hierfür sind ausgewählte normative Kriterien zur Güte von Steuerungsmustern. So wird z.B. gezielt die politische Entscheidungskapazität in den beobachteten Mustern betrachtet: Während etwa in Deutschland auf die Studierendenproteste 2009 im Rahmen des interventionistischen Musters mit verbindlichen Instrumenten wie Strukturvorgaben, Akkreditierung und letztlich dem Qualitätspakt Lehre nicht nur symbolisch reagiert werden konnte, stand das Wiener Wissenschaftsministerium den starken Protesten durch den Verzicht auf regulative und finanzielle Ressourcen hilflos gegenüber.
Auf dieser Basis werden abschließend einige grundlegende Anregungen zur Weiterentwicklung des deutschen Hochschulsystems gegeben. Unter anderem wird dafür plädiert, den hochschulpolitischen Reformdiskurs, der sich oftmals nur zwischen den Polen `mehr Staat` und `mehr Wettbewerb` zu bewegen scheint, gezielt um alternative Handlungslogiken und Akteure zu erweitern: Die Ergebnisse der Arbeit legen nahe, Verbände und Organisationen (Rektorenkonferenzen, Fachgesellschaften, Fakultätentage u.a.) politisch zu stärken, um diese Sichtweisen und Expertisen in zukünftigen Reformprozessen (z.B. aktuell Digitalisierung) systematischer als zuvor miteinzubeziehen. Denn eine zu starke Entkopplung von politischen und wissenschaftlichen Rationalitäten führt unweigerlich zu nicht intendierten Effekten, die ihrerseits wieder Handlungsdruck erzeugen (z.B. Proteste).
Ecological assessment approaches based on benthic invertebrates in Euphrates tributaries in Turkey
(2019)
Sustainable water management requires methods for assessing ecological stream quality. Many years of limnological research are needed to provide a basis for developing such methods. However, research of this kind is still lacking in Turkey. Therefore, the aim of this doctoral thesis was to provide basic research in the field of aquatic ecology and to present methods for the assessment of ecological stream quality based on benthic invertebrates. For this purpose, I selected 17 tributaries of the Euphrates with a similar typology/water order and varying levels of pollution or not affected by pollution at all. The characterisation of the natural mountain streams was the first important step in the analysis of ecological quality. Based on community indices, I found that the five selected streams had a very good ecological status. I also compared the different biological indications, collected on two occasions ¬– once in spring (May) and once in autumn (September) – to determine the optimal sampling time. The macroinvertebrate composition differed considerably between the two seasons, with the number of taxa and Shannon index being significantly higher in autumn than in spring. In the final step, I examined the basal resources of the macroinvertebrates in the reference streams with an isotope analysis. I found that FPOM and biofilm were the most relevant basal resources of benthic invertebrates. Subsequently, based on the similarity of their community structures, I divided the 17 streams into three quality classes, supported by four community indices (EPT [%], EPTCBO [%], number of individuals, evenness). In this process, 23 taxa were identified as indicators for the three quality classes. In the next step, I presented two new or adapted indices for the assessment of quality class. Firstly, I adapted the Hindu Kush-Himalaya biotic index to the catchment area of the Euphrates and created a new, ecoregion-specific score list (Euph-Scores) for 93 taxa. The weighted ASPT values, which were renamed the Euphrates Biotic Score (EUPHbios) in this study, showed sharper differentiations of quality classes compared to the other considered ASPT values. Thus, this modified index has proved to be very effective and easy to implement in practical applications. As a second biological index, I suggested the proportion of habitat specialists. To calculate this index, the habitat preferences of the 20 most common benthic invertebrates were identified using the new habitat score. The proportion of habitat specialists differed significantly among the three quality classes with higher values in natural streams than in polluted streams. The methods and results presented in this doctoral thesis can be used in a multi-metric index for a Turkish assessment programme.
Streams are coupled with their riparian area. Emerging insects from streams can be an important prey in the riparian area. Such aquatic subsidies can cause predators to switch prey or increase predator abundances. This can impact the whole terrestrial food web. Stressors associated with agricultural land use can alter insect communities in water and on land, resulting in complex response patterns of terrestrial predators that rely on prey from both systems.
This thesis comprises studies on the impact of aquatic nsects on a terrestrial model ecosystem (Objective 1, hapter 2), the influence of agricultural land use on riparian spiders’ traits and community (Objective 2, Chapter 3), and on the impact of agricultural land use on the contribution of different prey to spider diet (Objective 3, Chapter 4).
In chapter 2, I present a study where we conducted a mesocosm experiment to examine the effects of aquatic subsidies on a simplified terrestrial food web consisting of two types of herbivores (leafhoppers and weevils), plants and predators (spiders). I focused on the prey choice of the spiders by excluding predator immigration and reproduction. In accordance with predator switching, survival of leafhoppers increased in the presence of aquatic subsidies. By contrast, the presence of aquatic subsidies indirectly reduced weevils and herbivory.
In chapter 3, I present the results on the taxonomic and trait response of riparian spider communities to gradients of agricultural stressors and environmental variables, with a particular emphasis on pesticides. To capture spiders with different traits and survival strategies, we used multiple collection methods. Spider community composition was best explained by in-stream pesticide toxicity and shading of the stream bank, a proxy for the quality of the habitat. Species richness and the number of spider individuals, as well as community ballooning ability, were negatively associated with in-stream pesticide toxicity. In contrast, mean body size and shading preference of spider communities responded strongest to shading,
whereas mean niche width (habitat preference for moisture and shading) responded strongest to other environmental variables.
In chapter 4, I describe aquatic-terrestrial predator-prey relations with gradients of agricultural stressors and environmental variables. I sampled spiders, as well as their aquatic and terrestrial prey along streams with an assumed pesticide pollution gradient and determined their stable carbon and nitrogen signals. Potential aquatic prey biomass correlated positively with an increasing aquatic prey contribution of T. montana. The contribution of aquatic prey to the diet of P. amentata showed a positive relationship with increasing toxicity in streams.
Overall, this thesis contributes to the emerging discipline of cross-ecosystem ecology and shows that aquatic-terrestrial linkages and riparian food webs can be influenced by land use related stressors. Future manipulative field studies on aquatic-terrestrial linkages are required that consider the quality of prey organisms, fostering mechanistic understanding of such crossecosystem effects. Knowledge on these linkages is important to improve understanding of consequences of anthropogenic stressors and to prevent further losses of ecosystems and their biodiversity.
Die Nachhaltigkeitsberichterstattung kann als ein zentrales Element einer konsequenten Unternehmensstrategie zur Umsetzung der gesellschaftlichen Verantwortung (Corporate Social Responsibility) angesehen werden. Um die Unternehmen bei dieser Aufgabe zu unterstützen stellt die Global Reporting Initiative (GRI) mit ihren G4 Leitlinien einen Orientierungsrahmen bereit, dessen Anwendung sich allerdings für Klein und Mittelunternehmen sehr komplex gestaltet. Ein branchenspezifisches Sector Supplement für den Weinbau existiert derzeit noch nicht.
Ziel der vorliegenden Arbeit ist es, diese Forschungslücke durch die Entwicklung weinbauspezifischer Nachhaltigkeitsaspekte und Indikatoren zu schließen, um den Betrieben eine selbstständige GRI-konforme Berichterstattung zu ermöglichen.
Der Prozess zur Identifikation wesentlicher Nachhaltigkeitsaspekte und -indikatoren erfolgt mittels Erhebungs- und Auswertungsmethoden der qualitativen Sozialforschung in Form
von Workshops, betrieblichen Vorortanalysen und Experteninterviews.
Parallel dazu erfolgt eine umfassende Analyse der weinbaulichen Wertschöpfungskette in Form einer Internet- und Literaturrecherche. Diese umfasst vorrangig die ökologischen Nachhaltigkeitsaspekte als diejenigen Bestandteile weinbaulicher Tätigkeiten, die sich sowohl positiv als auch negativ auf die Umwelt auswirken können. Anschließend erfolgt die zentrale Priorisierung der identifizieren Handlungsfelder und Nachhaltigkeitsthemen durch die Stakeholder. Zur Visualisierung der bewerteten Handlungsfelder dient das Instrument der Wesentlichkeitsanalyse.
Auf dieser Basis erfolgt die Entwicklung eines Handlungsleitfadens zur Erstellung von Nachhaltigkeitsberichten in der Weinwirtschaft. Hiermit erlangen Weingüter die praktische Kompetenz ein eigenes Nachhaltigkeitsreporting anzugehen.
Im Rahmen der Arbeit wurde auch ein elektronisches Tool entwickelt, das den Betrieben die Möglichkeit eröffnet, betriebliche Umweltaspekte zu erfassen und zu bewerten. Gleichzeitig wird den Anwendern damit die Generierung eines überbetrieblichen Vergleichs der Umweltleistung ermöglicht (Benchmarking).
Eine weitere Forschungsfrage der vorliegenden Arbeit beschäftigt sich mit der Biodiversitätserfassung und -bewertung für Rebland. Hintergrund sind die bisher nur geringen Funde auf der durch das Bundesamt für Naturschutz festgelegten Kennartenlisten bzw. den HNV-Stichprobenflächen (High nature value farmland-Indikator) für Rebland.
Hierzu wurde mittels Geoinformationssystemen das Artenvorkommen in rheinland-pfälzischen Weinanbaugebieten analysiert und 30 Pflanzenarten als Indikatorarten für den Weinbau abgeleitet. Ergänzend wurden weinbergstypische, geschützte Tierarten als „Bonusarten“ identifiziert. Die Indikatorarten werden den Winzern als ein Instrument zur eigenständigen Erfassung der Biodiversität in den Weinbergen dienen und im Rahmen einer Nachhaltigkeitsberichterstattung herangezogen werden können.
Refractory dry-vibratable mixes, which consist of a mineral filling material and an organic or anorganic binder system, are widely used for linings in industrial aggregates, where a very high temperature resistance is required (e.g. steel industry). During lining, all compounds are mixed and hardening is chemically or thermally initiated. The time span required for hardening is of special relevance for the application of refractory dry-vibratable mixes. It should be long enough for adequate processability, but simultaneously avoid too long downtimes. Prediction or regulation of the hardening time, necessary for an ideal processing, is currently limited. One the one hand, this is a result of the lack of an appropriate method for time-dependent determination of the harding process. On the other hand, the mechanisms responsible for this very complex process have not yet been investigated in detail and the effect of influencing factors, like the temperature or the composition of the refractory dry-vibratable mixes, are poorly documented.
To make a contribution to the understanding of the hardening mechanism of refractory dry-vibratable mixes, it was the aim of the present work, to develop an appropriate test method for the time-dependent investigation of this process. This was realized by means of the dynamic-mechanical analysis. In addition, the hardening mechanism was described for a refractory dry-vibratable mix with a binder system, which consists of a waterglass and a phosphate hardener (AlPO4 und BPO4), using supplement gravimetric investigations and determining solubility behavior of the phosphates. By means of X-ray diffraction analysis, nuclear magnetic resonance spectroscopy and scanning electron microscopy, the impact of the hardening mechanism on the crystal and amorphous structure was studied. It could be shown, that according to the two phosphates, the hardening leads to different network structures in respect of their link denseness. These structure characteristics correlate with the speed of the hardening reactions. In addition, the impact on selected properties (thermal linear deformation, temperature-dependent phase development and phase transition) could be deducted.
Gegeben sei eine Basis b>=10 und eine Ziffer a0 aus der Menge {0,..., b − 1}. Wir untersuchen, ob es unendlich viele Primzahlen gibt, die in ihrer b-adischen Zifferndarstellung die Ziffer a0 nicht besitzen. Ferner schätzen wir die Anzahl dieser Primzahlen, die kleiner sind als X = b^k, nach oben und unten ab.
Damit gelingt uns eine Verallgemeinerung von Maynards Beweis für den Fall b = 10 und wir nutzen hierzu auch die in seiner Arbeit verwendeten Werkzeuge. Unter Anderem benötigen wir die Hardy-Littlewoodsche Kreismethode sowie diverse Siebmethoden, um die Minor Arcs zu kontrollieren.
Schließlich sehen wir, dass wir Maynard's Aussage vor allem dann auf beliebige Basen b>= 10 und ausgeschlossene Ziffern a0 aus {0, ..., b − 1} übertragen können, wenn zwei betragsmäßig größte Eigenwerte von Matrizen, die von b und a0 parametrisiert werden, bestimmte Abschätzungen erfüllen. Dass diese Abschätzungen im Fall b>=102 erfüllt sind, beweisen wir im letzten Kapitel. Für die Fälle b = 10 und b = 11 liegt ebenfalls ein Mathematica-Code vor, der die Abschätzungen bestätigt.
Groundwater is essential for the provision of drinking water in many areas around the world. The ecosystem services provided by groundwater-related organisms are crucial for the quality of groundwater-bearing aquifers. Therefore, if remediation of contaminated groundwater is necessary, the remediation method has to be carefully selected to avoid risk-risk trade-offs that might impact these valuable ecosystems. In the present thesis, the ecotoxicity of the in situ remediation agent Carbo-Iron (a composite of zero valent nano-iron and active carbon) was investigated, an estimation of its environmental risk was performed, and the risk and benefit of a groundwater remediation with Carbo-Iron were comprehensively analysed.
At the beginning of the work on the present thesis, a sound assessment of the environmental risks of nanomaterials was impeded by a lack of guidance documents, resulting in many uncertainties on selection of suitable test methods and a low comparability of test results from different studies with similar nanomaterials. The reasons for the low comparability were based on methodological aspects of the testing procedures before and during the toxicity testing. Therefore, decision trees were developed as a tool to systematically decide on ecotoxicity test procedures for nanomaterials. Potential effects of Carbo-Iron on embryonic, juvenile and adult life stages of zebrafish (Danio rerio) and the amphipod Hyalella azteca were investigated in acute and chronic tests. These tests were based on existing OECD and EPA test guidelines (OECD, 1992a, 2013a, 2013b; US EPA, 2000) to facilitate the use of the obtained effect data in the risk assessment. Additionally, the uptake of particles into the test organisms was investigated using microscopic methods. In zebrafish embryos, effects of Carbo-Iron on gene expression were investigated. The obtained ecotoxicity data were complemented by studies with the waterflea Daphnia magna, the algae Scenedesmus vacuolatus, larvae of the insect species Chironomus riparius and nitrifying soil microorganisms.
In the fish embryo test, no passage of Carbo-Iron particles into the perivitelline space or the embryo was observed. In D. rerio and H. azteca, Carbo-Iron was detected in the gut at the end of exposure, but no passage into the surrounding tissue was detected. Carbo-Iron had no significant effect on soil microorganisms and on survival and growth of fish. However, it had significant effects on the growth, feeding rate and reproduction of H. azteca and on survival and reproduction in D. magna. Additionally, the development rate of C. riparius and the cell volume of S. vacuolatus were negatively influenced.
A predicted no effect concentration of 0.1 mg/L was derived from the ecotoxicity studies based on the no-effect level determined in the reproduction test with D. magna and an assessment factor of 10. It was compared to measured and modelled environmental concentrations for Carbo-Iron after application to an aquifer contaminated with chlorohydrocarbons in a field study. Based on these concentrations, risk quotients were derived. Additionally, the overall environmental risk before and after Carbo-Iron application was assessed to verify whether the chances for a risk-risk trade-off by the remediation of the contaminated site could be minimized. With the data used in the present study, a reduced environmental risk was identified after the application of Carbo-Iron. Thus, the benefit of remediation with Carbo-Iron outweighs potential negative effects on the environment.
The dissertation examines the self-concept of Indian religious women in German care institutions. For the analysis, the method of grounded theory was selected from empirical social research. The investigation field interviewed 26 Indian religious women and 5 employers. The theoretical foundations of mission history were the standard of the missionary ministry, the expression of the German and Indian concept of care, the concept of culture in its structural conditionality of dimensions and models with reference to the organization "religious community".
The direct relation to the research question was served by the hierarchical self-concept model according to Shalveson and another model by Bracken, which was used to interpret the empirical results. In the five core categories and their subcategories, the main motive was "being a missionary". Indian religious women refer to themselves as "European missionaries" and want to bring the love of Christ to the sick, the needy and the elderly through their care and nursing work.
In order for the Indian religious women to be able to work even more optimally in their self-concept in Germany, it is advisable to develop a requirement profile, to consider certain framework conditions in advance and to design new models of life.
Sediment transport contributes to the movement of inorganic and organic material in rivers. The construction of a dam interrupts the continuity of this sediment transport through rivers, causing sediments to accumulate within the reservoir. Reservoirs can also act as carbon sinks and methane can be released when organic matter in the sediment is degraded under anoxic conditions. Reservoir sedimentation poses a great threat to the sustainability of reservoirs worldwide, and can emit the potent greenhouse gas methane into the atmosphere. Sediment management measures to rehabilitate silted reservoirs are required to achieve both better water quantity and quality, as well as to mitigate greenhouse gas emissions.
This thesis aims at the improvement of sediment sampling techniques to characterize sediment deposits as a basis for accurate and efficient water jet dredging and to monitor the dredging efficiency by measuring the sediment concentration. To achieve this, we investigated freeze coring as a method to sample (gas-bearing) sediment in situ. The freeze cores from three reservoirs obtained were scanned using a non-destructive X-Ray CT scan technique. This allows the determination of sediment stratification and character-ization of gas bubbles to quantify methane emissions and serve as a basis for the identi-fication of specific (i.e. contaminated) sediment layers to be dredged. The results demon-strate the capability of freeze coring as a method for the characterization of (gas-bearing) sediment and overcomes certain limitations of commonly used gravity cores. Even though the core’s structure showed coring disturbances related to the freezing process, the general core integrity seems to not have been disturbed. For dredging purposes, we analyzed the impact pressure distribution and spray pattern of submerged cavitating wa-ter jets and determined the effects of impinging distances and angles, pump pressures and spray angles. We used an adapted Pressure Measurement Sensing technique to enhance the spatial distribution, which proved to be a comparatively easy-to-use meas-urement method for an improved understanding of the governing factors on the erosional capacity of cavitating water jets. Based on this data, the multiple linear regression model can be used to predict the impact pressure distribution of those water jets to achieve higher dredging accuracy and efficiency. To determine the dredging operational efficien-cy, we developed a semi-continuous automated measurement device to measure the sediment concentration of the slurry. This simple and robust device has lower costs, compared to traditional and surrogate sediment concentration measurement technolo-gies, and can be monitored and controlled remotely under a wide range of concentrations and grain-sizes, unaffected by entrained gas bubbles
Computer modelling of human partial body structures is becoming increasingly important for medical application. This is an interdisciplinary field of research in which new methods can be developed through the cooperation of physics, mathematics, computer visualistics and medicine. These methods can be used to make more precise statements about the mechanical loads of internal force-transmitting structures, such as intervertebral discs, ligaments, joints and muscles, during motion sequences.
At the beginning of this work, the importance of the need for research in computer modeling, specialized in the area of the spine, is presented.
In the following, the basic anatomical structures will be discussed, including intervertebral discs, ligaments, facet joints and musculature.
Algorithms are then developed to create individual lumbar spine models from CT data in a short time and semi-automatically. Methods will be developed to model the presented force transmitting structures of the spine, such as the intervertebral discs, ligaments, facet joints and muscles.
In addition different imaging methods (MRT data, x-ray film, x-ray functional images) will be presented and validate the lumbar spine models.
Finally, the algorithms developed will be used to create a larger number of individual lumbar spine models, which will then be examined for similarities and differences with regard to internal loads as well as for physiologically correct movement sequences. In particular, the relative momentary center of rotation between two adjacent vertebrae is calculated.
While the existing literature on cooperative R&D projects between firms and public research institutes (PRI) has made valuable contributions by examining various factors and their influence on different outcome measures, there has been no investigation of cooperative R&D project success between firms and PRI from a product competitive advantage perspective. However, insights into the development of a meaningful and superior product (i.e., product competitive advantage) are particularly important in the context of cooperative R&D projects between PRI and (mainly small and medium-sized) firms in the biotechnology industry in response to increasing competition to raise capital funds necessary for survival.
The objectives of this thesis are: (1) to elaborate the theoretical foundations which explain the achievement of a product competitive advantage in cooperative R&D projects between biotechnology firms and PRI, (2) to identify and empirically evaluate the determining factors for achieving a product competitive advantage in cooperative R&D projects between biotechnology firms and PRI, and (3) to show how cooperative R&D projects between biotechnology firms and PRI should be designed and executed to support the achievement of a product competitive advantage.
To accomplish these objectives, a model of determinants of product competitive advantage in cooperative R&D projects between biotechnology firms and PRI is developed by drawing from the theoretical foundations of resource-based theory and information-processing theory. The model is evaluated using data from 517 questionnaires on cooperative R&D projects between at least one biotechnology firm and one PRI. The data are analyzed using variance-based structural equation modeling (i.e., PLS-SEM) in order to conduct hypotheses testing. The evaluation of the empirical data includes an additional mediation analysis and the comparison of effects in subsamples.
The results demonstrate the importance of available resources and skills, as well as the proficient execution of marketing-related and technical activities for the achievement of a product competitive advantage in cooperative R&D projects between biotechnology firms and PRI. By identifying project-related and process-related factors affecting product competitive advantage and empirically testing their relationships, the research findings should be valuable for both researchers and practitioners. After discussing contributions and implications for research and practice, the present thesis concludes with limitations and avenues for future research.
In the present dissertation, the structural interaction between potassium waterglass and aluminium metaphosphates (aluminium tetrametaphosphate and aluminium hexametaphosphate) were investigated in terms of the resettlement behaviour of the metaphosphates as hardening agents. The crystalline phase composition was described qualitatively and quantitatively in terms of powder diffraction patterns combined with Rietveld refinement. The amorphous phase content was determined by different spectroscopic methods (e.g. solid-state NMR, ATR-IR, and Raman spectroscopy). The solubility behaviour of the chemical hardening agents was investigated by optical emission spectroscopy and electron absorption spectroscopy. The mechanical properties of the samples were measured by three-point bending tests, resonance damping frequency analysis, and acid test. The structural framework of the chemically hardened waterglasses was explored by scanning electron microscopy method. It could be proven, that the reaction mechanism of the resettlement is strongly dependent on the structure of the aluminium metaphosphate. After the dissolution of the aluminium ions of aluminium tetrametaphosphate through the alkalic environment of the potassium waterglass, a potassium tetrametaphosphate is developed through an ion-exchange reaction with the waterglass` potassium ions. In the hexametaphosphate system, no analogous structure could be proven. Parallel to the ion-exchange reaction an incremental depolymerization of the cyclic metaphosphate structure to the final crystalline product potassium dihydrogen phosphate occurs. The drop in pH value due to the addition of the respective aluminium metaphosphate initiates a polycondensation of the potassium waterglass due to the decreasing stabilization of the waterglass. This process is increased by the depolymerization products of the metaphosphate, that remove further quantities of the alkali ions, which accelerates the polycondensation reaction due to a further decrease in pH value. The dissolved aluminium ions from the aluminium metaphosphate penetrate into the amorphous, hardening silica network and develops an alumosilicate binder matrix. Furthermore, amorphous hydrated aluminium phosphate phases develop in separate domains beside silicate, alumosilicate phases, and the crystalline phase contents e.g. potassium dihydrogenphosphate and the incomplete reacted aluminium metaphosphate. Consequently, the chemically hardened potassium waterglass binder is not necessarily homogenous. Regarding the mechanical and chemical properties, in summary with increasing alkali modulus the mechanical flexural strength, and the young modulus drop, while the chemical resistance towards acid attack, and the porosity of the samples increase. The change in the cyclic structure from aluminium tetrametaphosphate to aluminium hexametaphosphate leads to a drop in the acid resistance, the porosity of the samples, the flexural strength, and the young modulus.
Carabids, which are frequently distributed in agricultural landscapes, are natural enemies of different pests including slugs. Semi-natural habitats are known to affect carabids and thus, their potential to support natural pest control.
The impact of semi-natural habitats was investigated on carabids and slugs within different non-crop habitats (chapter 2). Most carabids and Deroceras reticulatum showed preferences for herbaceous semi-natural habitats, while Arion spp. occured mainly in woody habitats. An increase of predatory carabid abundance, which was linked to an inclining amount of semi-natural habitats in the landscape, and a decrease of Arion spp. densities, indicated a high potential for slug control in structural rich landscapes.
Effects of semi-natural habitats were investigated on predatory carabids and slugs in 18 wheat fields (chapter 3). Predatory carabid species richness was positively affected by the increasing amount of semi-natural habitats in the landscape, whereas predatory carabid abundance was neither influenced by adjacent habitat type nor by the proportion of semi-natural habitats in the landscape. The target pest species showed divergent patterns, whereas Arion spp. densities were highest in structural poor landscapes near woody margins. D. reticulatum was not affected by habitat type or landscape, reflecting its adaptation to agriculture. Results indicate an increased control of Arion spp. by carabids in landscapes with a high amount of semi-natural habitats.
Effects of semi-natural habitats and the influence of farming system was tested on carabid distribution within 18 pumpkin fields (chapter 4). Carabid species richness generally increased with decreasing distance to the field margins, whereas carabid abundance responded differently according to the adjacent habitat type. Farming system had no effect on carabids and landscape heterogeneity only affected carabids in organic pumpkin fields.
Slug and slug egg predation of three common carabid species was tested in single and double species treatments in the laboratory (chapter 5). Results show additive and synergistic effects depending on the carabid species. In general, semi-natural habitats can enhance the potential of slug control by carabids. This counts especially for Arionid slugs. Semi-natural habitats can support carabid communities by providing shelter, oviposition and overwintering sites as wells as complementary food sources. Therefore, it is important to provide a certain amount of non-crop habitats in agricultural landscapes.
Previous research revealed that teachers hold beliefs about gifted students combining high intellectual ability with deficits in non-cognitive domains, outlined in the so-called disharmony hypothesis. Since teachers’ beliefs about giftedness can influence which students they identify as gifted, the empirical investigation of beliefs is of great practical relevance. This dissertation comprises three research articles that investigated teacher beliefs about gifted students’ characteristics in samples of pre-service teachers using an experimental vignette approach. Chapter I starts with a general introduction into beliefs, and presents the research aims of the present dissertation. The first article (Chapter II) focused on the interaction of beliefs about giftedness and gender in a sample of Australian pre-service teachers and tested if social desirability occurred when using the vignette design. Beside evidence for beliefs in line with the disharmony hypothesis, results revealed typical gender stereotypes. However, beliefs about giftedness appeared not to be gender specific and thus, to be similar for gifted girls and boys. The vignette approach was found to be an adequate design for assessing teacher beliefs. The second article (Chapter III) investigated teacher beliefs and their relationship to motivational orientations for teaching gifted students in a cross-country sample of German and Australian pre-service teachers. Motivational orientations comprise cognitive components (self-efficacy) and affective components (enthusiasm). Findings revealed beliefs in the sense of the disharmony hypothesis for pre-service teachers from both countries. Giftedness when paired with beliefs about high maladjustment was found to be negatively related to teachers’ self-efficacy for teaching gifted students. The third article (Chapter IV) examined the role of teachers’ belief in a just world for the formation of beliefs using a sample of Belgian pre-service teachers. It was found that the stronger pre-service teachers’ belief in a just world was, the more they perceived gifted students’ high intellectual ability as unfair and thus, neutralized that injustice by de-evaluating students’ non-cognitive abilities. In a general discussion (Chapter V), findings of the three articles are combined and reflected. Taken together, the present dissertation showed that teacher beliefs about gifted students’ characteristics are not gender specific, generalizable over countries, negatively related to teacher motivation and can be driven by fairness beliefs.
Grapevine growers have struggled with defending their crops against pests and diseases since the domestication of grapevine over 6000 ears ago. Since then, new growing methods paired with a better nderstanding of the ecological processes in the vineyard ecosystem continue to improve quality and quantity of grape harvests. In this thesis I am describing the effects of two recent innovations in viticulture on pest and beneficial arthropods in vineyards; Fungus-resistant grapevine cultivars (PIWIs) and the pruning system semi-minimal pruned hedge (SMPH). The SMPH pruning system allows for a drastic reduction of manual labor in the vineyard, and PIWIs are resistant to two of the most common fungal diseases of grapevine and therefore allow a drastic reduction of fungicide applications compared to conventional varieties. Heavy use of pesticides is linked to a number of problems, including pollution of waterways, negative effects on human health, and biodiversity loss. Here, I studied the effects of fungicide reduction and minimal pruning on arthropods that are beneficial for natural pest suppression in the vineyard ecosystem such as predatory mites, spiders, ants, earwigs, and lacewings. All of these groups either benefitted from the reduction of fungicide sprayings or were not significantly affected. Structural changes in the canopy of SMPH grapevines altered the microclimate in the canopy which in turn influenced some of the arthropods living in it. Overall, my findings suggest that PIWIs and SMPH, both in combination or separately, improve conditions for natural pest control. This adds to other advantages of these innovative management practices such as a reduction in production cost and a smaller impact on the environment.
Will Eisners Graphic Novels zeugen von einer tiefgehenden Identitifation mit dem Judentum als Volkszugehörigkeit, Religion und Kultur und spiegeln das Judentum in all seinen Facetten wider. Dabei ist besonders hervorzuheben, dass die Entwicklung des Gesamtwerks parallel verläuft zur Geschichte der Emanzipation der jüdischen Bevölkerung in New York City. Der Band clustert die jüdischen Aspekte in Eisners Werk in beispielsweise Faktoren kollektiver Erinnerung, Umgang mit und Kampf gegen Antisemitismus und religiöse Besonderheiten.
Invasive species often have a significant impact on the biodiversity of ecosystems and the species native to it. One of the worst invaders worldwide is Aphanomyces astaci, the causative agent of the crayfish plague, an often fatal disease to crayfish species not native to North America. Aphanomyces astaci originates from North America and was introduced to Europe in the midst of the 19th century. Since then, it spread throughout Europe diminishing the European crayfish populations. The overall aim of this thesis was to evaluate the threat that A. astaci still poses to European crayfish species more than 150 years after its introduction to Europe. In the first part of the thesis, crayfish specimens, which are available in the German pet trade, were tested for infections with A. astaci. Around 13% of the tested crayfish were clearly infected with A. astaci. The study demonstrated the potential danger the pet trade poses for biodiversity through the import of alien species and their potential pathogens, in general. In the second part of the thesis, the A. astaci infection prevalence of crayfish species in wild populations in Europe was tested. While the stone crayfish, Austropotamobius torrentium, showed high susceptibility to different haplogroups of A. astaci, the narrow-clawed crayfish, Astacus leptodactylus, was able to survive infections, even by haplogroup B, which is considered to be highly virulent. In the last part of the thesis, A. astaci was traced back to its original distribution area of North America. While the crayfish plague never had such a devastating effect on crayfish in North America as it had in Europe, the reasons for the success of invasive crayfish within North America are not yet fully understood. It is possible that A. astaci increases the invasion success of some crayfish species. Several populations of the rusty crayfish, Orconectes rusticus, in the Midwest of North America were confirmed to be infected with A. astaci and a new genotype was identified, possibly indicating that each crayfish host is vector of a unique A. astaci genotype, even in North America. Overall, the present thesis provides evidence that A. astaci is still a major threat to the crayfish species indigenous to Europe. Crayfish mass mortalities still occur in susceptible crayfish species like A. torrentium even 150 years after the first introduction of A. astaci. While there are some indications for increased resistances through processes of co-evolution, the continuous introduction of crayfish species to Europe threatens to cause new outbreaks of the crayfish plague through the parallel introduction of new, highly virulent A. astaci strains.
Gefährdete Weltmacht USA
(2017)
Aims and findings of the dissertation
The completed research uses holistic, politological and historical approaches to present how, during the studied period of the administrations of Clinton to Obama, the liberal, rule-based world order system is gradually supplemented and replaced by a system of realist imposition of vital interests that have short-term effects, preferring military means combined with continuous military optimisation. This also explains a continuity between the leading-power policy of administrations in this study (1993-2017) and the subsequent period of the “transactional leadership of Trump”(1), with its recognizable, far-reaching effects of aiming to reduce idealistic Grand Strategy elements and measures of a benevolent order by passing on costs to and reducing the benefits of European NATO allies. The results of this dissertation, such as the increasingly evident dissolution of a multilateral fundamental order, therefore indicate that Trump’s foreign and security policy to date should be regarded as a clearly noticeable crisis symptom, rather than the cause of a decline in the world order established after 1945. This decline is synonymous with the erosion of the transatlantically initiated bipolar “American system”. Its implementation was the result of the “lesson of two world wars”, based on modern concepts of order introduced by the Enlightenment and the founding criteria of the United States: thus its dissolution is also an indicator of the failure of contemporary criteria of order that thrive in the “American way of life”.
The cause of the described development is shown to be a constantly exacerbating overall threat, from Clinton to Obama, which is connected to the consistent erosion of US supremacy. Among other aspects, this is based on climate change effects postulated in 1979, which multiply the threat while coinciding with American peak production of fossil fuels and increased demand on resources in the context of dwindling raw material resources. Furthermore, during the period of this study, the “US conservative revolution”, which began in the 1980s, increasingly affected foreign and security policy, combining with a consolidation in the influence of corporations and lobby groups in fields such as policy implementation and new underlying conditions. They include the onset of digitisation, entailing a high consumption of resources, and a growing world population faced with specific demographic indicators. Additionally, the maintenance of the armaments sector, originally a result of bipolar development, as the economic basis of military supremacy and the slow decline of the Dollar hegemony since around 1973, should also be taken into account. Complex interaction between Grand Strategy implementation according to the premise of expanding US-American dominance under neoconservative and Christian Right-wing influences, as well as asymmetrical and reactivated conventional security threats and threat multipliers clearly indicate the linear development of the overall threat in the period between 1993 and 2017: in the context of Grand Strategy statements, above all the understanding of defence against this threat, of the latter’s multiplying factors and the market economy explains the following with respect to the US far-right in a complex interaction with the growth of transnational corporations, lobby groups, individuals(2), informal networks and state actors with respect to objects of threat and threat multipliers(3) in connection with the post-bipolar, global anchoring of US economic and consumer patterns: US adaptation of its reaction to this threat – while consolidating imperial presidency(4) and weakening the system of checks and balances – including its implications of a bipolar liberal order. In this way, the necessary continued leadership within NATO through the US-proposed NATO reform can be seen as an appropriate implementation of transformed threat-reaction measures and the legitimisation of systemic adaptation. It equally becomes clear that the established threat reaction measures only provide a short-term defence: instead, they enhance the asymmetric and conventional threat, as well as threat multipliers – by introducing arms races and breaking down arms control – thereby heightening the overall threat. The consequence is the consistently growing likelihood of a conflict of hitherto unimaginable proportions. At the same time, the urgent need to mobilise transatlantic cooperation with respect to supporting global cooperation between state and non-government actors is illustrated with respect to the roots of the threat and its deteriorating underlying conditions: each increase in the overall threat, the adapted US security policy and its continuation in NATO is connected to an erosion of rule-based underlying criteria during the studied period. This continuously and consistently undermines the basis of the above-stated, ever-increasingly important cooperation, to prevent or at least limit the successive erosion of the bipolar “American system” under future dystopias. The research results completely overturn the state of research to date, since for instance it is possible to show that, by means of NATO transformation findings, no transatlantic sharing of burdens on an equal footing and no NATO reform in accordance with its founding principles can be achieved. The same also applies to European opposition to the actual anchoring of NATO transformation positions(5), which is based on the erosion of the bipolar liberal order system and the maintenance of US advantages as well as the consolidation of particular interests they facilitate. Furthermore, it is apparent that a line of continuity in the threat-reaction measures from Clinton to Obama exists with varying external effects, along with an underlying pattern of “Battleship America” – as opposed to a multilaterally orientated foreign and security policy under Clinton, which merged into a unilateral, radical swing under G. W. Bush 43 following 9/11, but was reverted by the Obama administration. A comprehensive wealth of literature was used of the doctoral thesis, as reflected by the extensive bibliography: they firstly include diverse American and European publications, monographs and relevant secondary literature, including biographies, publications of various kinds of important political planning and implementation, as well as collected volumes and research articles from specialist journals on all fields of research and politological methodology and theory. The same applies to publications by leading European and American institutions, research centres and think tanks. Furthermore, this author used publications and documents by governments, foreign ministries, defence ministries, other government bodies and Nato.
Dissertation structure
This dissertation is divided into two volumes and one Appendix: Volume 1 discusses Focus 1, namely a process-tracing in the context of offensive neorealist positioning. Volume 2 presents Focus 2, which is based on the preceding focus in making a structured, focussed comparison in the context of defensive neorealist positioning. The Appendix volume contains further discussion of Chapter 1, Volume 1 with respect to the state of research, literature and sources, theoretical positioning and the choice of the region of study and selected European NATO partners. Furthermore, a historical chapter provides underlying information for process-tracing in Chapter 2, Volume 1, an index of images and abbreviations, and a bibliography.
The entire dissertation uses qualitative methods to focus on these two mutually supporting, building on each other, themes to investigate the following from a US-perspective: firstly the overriding US security-policy reaction to a new overall threat and secondly, its continuation combined with the opportunity of for enabling and legitimising it within and through NATO during the studied period from Clinton to Obama.
Based on the first part of this hypothesis, Focus 1 (Volume 1) establishes a connection between, on the one hand, maintaining the bipolar Grand Strategy target of consolidating the USA as a leading, regulating power, bipolar foreign-policy Grand Strategy indicators and a new overall threat that is developing in a complex way, and, on the other, the necessity of its continued leadership within NATO and the required NATO transformation according to US-proposed NATO transformation positions.
Focus 2 (Volume 2) is based on the second part of the hypothesis, investigating the transatlantic negotiation process to establish these US-proposed NATO transformation positions: in this context, Volume 2 investigates whether the attempt to actually secure and consolidate such US supremacy was unsuccessful in the face of resistance from selected European NATO partners, namely France, Germany and the United Kingdom.
The overall result shows that due to a complex, developing, linear increase in the overall threat, the chance for the USA to consolidate its status as a leading power is steadily diminishing. This must be compensated by adapting US security policy. The resulting American security-policy realignment based on the initiated “revolution in military affairs” in turn modifies the indicators of bipolar collective security guarantees. Everything is enabled and legitimised by means of actually securing US NATO-transformation positions. The actual implementation of such NATO transformation – representing the consistent adaptation of US security policy – enables a mission-orientated, rapid response, flexible, global security projection. It also creates conditions for “alliances of choice” within NATO. Furthermore, the modification of a “bipolar NATO” exacerbates the erosion of key achievements of civilisation as a result of adapted US security policy, as well as undermining the tasks of bipolar collective security guarantees through diminished benefits to European NATO partners.
The actual anchoring of NATO transformation positions is achieved by reactivating the conventional threat in the context of the Ukraine crisis of 2014 and the extension of NATO partnership rings on a global level, without providing them with NATO membership status, thus avoiding globalisation in a mutual defence case. The German and French resistance is particularly intensive through the involvement of European founder states, while the formation of a European leadership triumvirate consisting of France, Germany and the United Kingdom does not take place.
Moreover, a relevant investigation of causes particularly shows that despite constant mutually supporting US security reaction measures with varying international effects and actual continued leadership within NATO, the overall threat is not receding: this leads to a constant increase in the overall threat, a loss of influence of state actors, the diffusion and concentration of power and the increased probability of reactive conventional, nuclear, cyber and ecological destruction scenarios. On this basis, the consequence is an increasingly comprehensive and rapidly responding precision defence combined with growing securitization to compensate for the ongoing containment of US supremacy. This developing process steadily diminishes the reach and power of a liberal, rule-based, bipolar “American system” and the establishment of “idealistic, liberal” elements of US-Grand Strategy. This entails a further reduction in benefits for European NATO allies and increasing US cost-cutting demands – based on the successive NATO transformation positions that build on each other and Obama’s “smart power”(6) during the period studied in this dissertation. Thus the chance is receding of developing the post-bipolar, globally adopted American way of life with individual national character, which is regarded as “non-negotiable”: for instance its articulation is expressed through increasing right-wing populism, the election of outsider-candidates, the dissolution of traditional party systems, isolationist tendencies combined with burgeoning ethnic, regional movements, the rejection of supranationalism, and religious fundamentalism. At the same time, the ongoing erosion of global public goods is apparent.
This all paves the way to limiting the benevolent American regulating power and state actors’ leverage – and therefore to a return to classic power politics in the context of a resulting diffusion and concentration of power. In view of the urgency of a long-term containment of asymmetrical or conventional threats to security, or aspects that exacerbate such threats or clusters thereof, as well as underlying global conditions, this undermines the ability to achieve the following: to achieve transatlantic cooperation by broadening the range of levels and actors in the spirit of proactive and expanded, networked security to achieve according global cooperation with respect to containing the root causes of threats.
Overall, this research work reveals how and why the anticipated “peace dividend” and the notion of an “age of hope”, as postulated by President Clinton, were hardly perceptible during the period of study between 1993 and 2017.
Notes
(1) Cf. Braml, Josef (2018), Trumps transaktionaler Transatlantizismus, in: Jäger, Thomas (Hrsg.), Zeitschrift für Außen- und Sicherheitspolitik, Oktober 2018, Volume 11, Ausgabe 4, S. 439-448, Wiesbaden.
(2) Cf. National Intelligence Council (Ed.) (2012), Global Trends 2013: Alternative Worlds (NIC 2012-001), https://publicintelligence.net/global-trends-2030/, last accessed: 12.04.19. See also the “international financial leadership, self-selected at Davos” cit. McCoy, Alfred W. (2017), In the Shadows of the American Century. The Rise and Decline of US Global Power, Chicago.
(3) In 1990, the threat-enhancing nature of climate change was already postulated with respect to asymmetric objects of threat as well as conventional and complex clusters: “Over the next half century, the global average temperature may increase by approximately 4 degrees C. (…) All nations will be affected. (…) How much time will there be to confirm the amount of change and then to act? (…) However, many believe that we will have waited too long to avoid major dislocation, hardship and conflict – on a scale not as yet seen by man“. Cf. Kelley, Terry P. (1990), Global Climate Change. Implications For The United States Navy (The United States Naval War College, Newport, RI), http://documents.theblackvault.com/documents/weather/climatechange/globalclimatechange-navy.pdf, last accessed: 30.03.19. Cf. Mazo, Jeffrey (2010), Climate Conflict. How global warming threatens security and what to do about it, London, Abingdon.
This supports the thesis of a developing, constant overall threat during the period between 1993 and 2017.
(4) Cf. Schlesinger, Arthur M., Jr. (1973), The Imperial Presidency, Boston.
(5) In this dissertation, the proposed US positions on NATO adaptation, the NATO Response Force and the Global Partnership Initiative are described as “NATO transformation positions”: Their actual establishment was connected to a NATO transformation with the consistent continuation of adapted US security policy.
(6) Cf. Nossel, Suzanne (2004), Smart Power. Reclaiming Liberal Internationalism, http://www.democracyarsenal.org/SmartPowerFA.pdf, last accessed: 26.08.17, Nye, Joseph S. Jr. (2011), The Future of Power, New York, Nye, Joseph S. Jr. (2011), Macht im 21sten Jahrhundert. Politische Strategien für ein neues Zeitalter, München, Rodham Clinton, Hillary (2010), Leading Through Civilan Power. Redefining American Diplomacy and Development, in: Foreign Affairs, November/December 2010, Vol. 89, No.6, S. 13-24.
Fachdidaktische und pädagogische Kompetenzen angehender Mathematiklehrkräfte für die Realschule
(2019)
Studien zur Wirksamkeit der Ausbildung von Lehrerinnen und Lehrern sind in der Regel fragebogenbasiert. In der vorliegenden Untersuchung wird ein anderer Ansatz gewählt, um die Kompetenzen angehender Mathematiklehrkräfte zu erheben und zu evaluieren. Die Studie untersucht anhand der unterrichtlichen Performanz, welche Kompetenzen Anwärterinnen und Anwärter in ihrer praktischen Ausbildung erworben haben. Der Analyse liegen 137 anonymisierte Niederschriften zu benote-ten Lehrproben von Anwärterinnen und Anwärtern im Fach Mathematik zugrunde. Diese bilden die Ausbildungsjahrgänge von 2004 bis 2011 ab. Die Anwärterinnen und Anwärter werden unterrichtspraktisch anhand der Niederschriften in Anlehnung an eine qualitative Inhaltsanalyse auf ihre Kompetenzausprägungen hin getestet. Dies erfolgt schwerpunktmäßig in den Bereichen Fachdidaktik, Fachmethodik, Classroom-Management und Gesprächsführung. Im Verlauf der Untersuchung wird deutlich, dass die Teilneh-mergruppe vor allem Stärken im methodischen Bereich hat. Hier können durchgehend gute Kompetenzausprägungen festgestellt werden. Über den gesamten Erhebungszeitraum zeigen sich hingegen in den Bereichen Classroom-Management und Gesprächsführung deutliche Defizite. Die fachdidaktischen Kompetenzen der angehenden Lehrkräfte entwickeln sich negativ: Ist zu Beginn der Erhebung noch etwa die Hälfte der Anwärterinnen und Anwärter im Bereich der Fachdidaktik zufriedenstellend einzustufen, gilt das im letzten Erhebungsjahrgang nur noch für knapp ein Fünftel der Probandinnen und Probanden. Es kann gezeigt werden, dass eine gute Notenfestsetzung eng mit den er-forderlichen Kompetenzen in der Fachdidaktik zusammenhängt.
Die vorliegende Studie bestätigt im Bereich der Fachdidaktik die Ergebnisse jener Studien, die auf Fragebögen basieren.
Es konnte zudem ein statistischer Zusammenhang zwischen den fachdidaktischen Fähigkeiten und den Steuerungskompetenzen hergestellt werden.
Student misbehavior and its treatment is a major challenge for teachers and a threat to their well-being. Indeed, teachers are obliged to punish student misbehavior on a regular basis. Additionally, teachers’ punishment decisions are among the most frequently reported situations when it comes to students’ experiences of injustice in school. By implication, it is crucial to understand teachers’ treatment of student misbehavior vis-à-vis students’ perceptions. One key dimension of punishment behavior reflects its underlying motivation and goals. People generally intend to achieve three goals when punishing misbehavior, namely, retribution (i.e., evening out the harm caused), special prevention (i.e., preventing recidivism of the offender), and general prevention (i.e., preventing imitation of others). Importantly, people’s support of these punishment goals is subject to hierarchy and power, implying that teachers’ and students’ punishment goal preferences differ. In this dissertation, I present three research projects that shed first light on teachers’ punishment and its goals along with the students’ perception of classroom intervention strategies pursuing these goals. More specifically, I first examined students’ (i.e., children’s) general support of each of the three punishment goals sketched above. Furthermore, I applied an attributional approach to understand and study the goals teachers intend to achieve when punishing student misbehavior. Finally, I investigated teachers’ and students’ support of the punishment goals regarding the same student misbehavior to directly compare their views on these goals and reactions pursuing them. In sum, the findings show that students generally prefer retribution and special prevention to general prevention, whereas teachers prefer general prevention and special prevention to retribution. This ultimately translates into a "mismatch" of teachers and students in their preferences for specific punishment goals, and the findings suggest that this may indeed enhance students’ perception of injustice. Overall, the results of the present research program may be valuable for the development of classroom intervention strategies that may reduce rather than enhance conflicts in student-teacher-interactions.
Die didaktische Konzeption der Schreibkonferenz ist soweit etabliert, dass sie bereits in den rheinland-pfälzischen Rahmenplan für die Grundschule für das Fach Deutsch übernommen wurde. Bisher liegt eine Reihe von Erfahrungsberichten zur Schreibkonferenz vor, jedoch wurden dazu bislang kaum systematisch empirische Untersuchungen durchgeführt. Die empirische Studie dieser Arbeit, welche an die VERA-Studie angeschlossen ist, untersucht, ob im Grundschulunterricht (in der dritten und vierten Klasse) der Einsatz von Schreibkonferenzen im Vergleich zur konventionellen Aufsatzdidaktik zu einer Verbesserung der Schreibleistungen, des eigenen Lernens, zu positiven Veränderungen des eigenen Verhaltens sowie zur Förderung der Motivation der Schüler beim Schreiben führt. Dabei wird von folgenden Überlegungen ausgegangen: Zum einen sollte die Schreibkonferenz im Gegensatz zur traditionellen Aufsatzdidaktik das selbstständige Arbeiten der Schüler mit Texten im Deutschunterricht fördern, zum anderen sollte sie zu einer intensiveren Auseinandersetzung mit Texten und damit zu einer Verbesserung des Aufsatzschreibens führen.
Engineering criminal agents
(2019)
This PhD thesis with the title "Engineering Criminal Agents" demonstrates the interplay of three different research fields captured in the title: In the centre are Engineering and Simulation, both set in relation with the application field of Criminology - and the social science aspect of the latter. More precisely,
this work intends to show how specific agent-based simulation models can be created using common methods from software engineering.
Agent-based simulation has proven to be a valuable method for social science since decades, and the trend to increasingly complex simulation models is apparent, not at least due to advancing computational and simulation techniques. An important cause of complexity is the inclusion of 'evidence' as basis of simulation models. Evidence can be provided by various stakeholders, reflecting their different viewpoints on the topic to model.
This poses a particular burden by interrelating the two relevant perspectives on the topic of simulation: on the one hand the user of the simulation model who provides the requirements and is interested in the simulation results, on the other hand the developer of the simulation model who has to program a verified and validated formal model. In order to methodically link these two perspectives, substantial efforts in research and development are needed, where this PhD thesis aims to make a contribution.
The practical results - in terms of software - were achieved by using the multi-faceted approach mentioned above: using methods from software engineering, in order to become able to apply methods from computational social sciences, in order to gain insights into social systems, such as in the internal dynamics of criminal networks.
The PhD thesis shows the research involved to create these practical results, and gives technical details and specifications of the developed software.
The frame for research and development to achieve these results was provided mainly by two research projects: OCOPOMO and GLODERS.
Zum Inhalt:
Die Dissertation ist in einem empirisch-qualitativen Forschungssetting eingebettet, bei der das Team-Teaching als Unterrichtsmethode im Forschungsfokus steht. Die Erhebung des empirischen Datenmaterials erfolgt einerseits mittels teilnehmender Beobachtung im Forschungsfeld und andererseits durch ein Gruppeninterview, das mit Lehrkräften geführt wird, die über einen gewissen Beobachtungszeitraum Erfahrungen mit der Unterrichtsmethode des Team-Teaching gesammelt haben. Für die hier zu Grunde gelegte Feldforschung wird das „theoretical sampling“ zum Einsatz kommen, das 1967 von Glaser und Strauss im Rahmen einer empirischen Untersuchung begründet worden ist.
Zum Aufbau:
In der Einleitung wird das Forschungsinteresse, der Forschungsstand und die zentrale Forschungsfrage der Dissertation beschrieben. Im zweiten Kapitel folgt der theoretische Teil mit einer differenzierten Definition des Team-Teachings als Unterrichtsmethode. Es folgt eine allgemeine Definition zum Unterricht, um die spezifischen Merkmale des Team-Teachings differenziert herausarbeiten zu können. Die empirischen Daten werden im Rahmen einer teilnehmenden Beobachtung im Unterricht der Oberstufe einer Förderschule mit dem Förderschwerpunkt Lernen und sozial-emotionale Entwicklung erhoben. Deshalb sind im Theorieteil der Förderschwerpunkt und die curricularen Aspekte zum Förderschwerpunkt dargestellt. Die Bedeutung der Unterrichtsmethode des Team-Teachings für das Unterrichtssetting in einer Förderschule mit dem sozial-emotionalem Förderschwerpunkt ist ebenfalls im Theorieteil verortet.
Im dritten Kapitel werden die qualitativen und quantitativen Erhebungsinstrumente beschrieben und Hypothesen formuliert. Die Darstellung der Methoden zur Aufbereitung des Datenmaterials ist im vierten Kapitel verortet. Die Interpretation der Forschungsergebnisse erfolgt im fünften Kapitel. Die qualitative und quantitative Datenauswertung des empirischen Datenmaterials ist im sechsten Kapitel dargestellt. Die Dissertation schließt im siebten Kapitel mit einen Fazit und Ausblick.
Nanotemplates for the combined structural and functional analysis of membrane-associated proteins
(2019)
Plasma membranes are essential for life because they give cells an identity. Plasma membranes are almost impermeable to fluids and substances. Still, transport between inside and outside needs to be possible. An important transport way is endocytosis. This mechanism relies on membrane-associated proteins that sense and induce curvature to the plasma membrane. However, the physics and structural dynamics behind proteins acting on membranes is not well understood. There is a standard method in vitro to investigate membrane-associated proteins sensing spherical geometries: They are incubated on unilamellar vesicles. This procedure allows to analyze these proteins in their bound state. This approach is inappropriate for GRAF1 (GTPase Regulator Associated with Focal Adhesion Kinase-1), a key player in endocytosis because it senses tubular geometries instead. However, GRAF1 extrudes lipid tubes from vesicles that can be analyzed. Still, this is a limited method because these tubes suffer from inhomogeneity and they do not enable the observation of intermediate and lower concentration binding states. To overcome this issue they can be incubated on pre-tubular structures called nanotemplates. There have been studies using carbon nanotubes and Galactosylceramide lipid tubes as nanotemplates. These approaches require complex chemical modifications or expensive components and they are not necessarily flexible. In this work we present a simple and easy new approach to prepare nanotemplates using Folch lipid mixture. We show on the basis of BPG, a truncate of GRAF1, that our nanotemplates are suitable for Cryo-EM and that it is possible to use IHRSR (Iterative Helical Real Space Reconstruction) to analyze the structure of BPG in its bound state. Moreover, the qualification for Cryo-EM allows to use plunge freezing to interrupt the incubation on our nanotemplates abruptly. This enables the analysis of intermediate binding states to understand the binding process.
In this thesis, I present the results of my studies on taxonomy, systematics, and biogeography of Impatiens (Balsaminaceae) in Madagascar and the Comoro islands.
In Chapter 1 I reviewed the literature on taxonomy and classification of Balsaminaceae, on habitat, world distribution, morphology, molecular phylogenetics and infrageneric classification of the genus Impatiens. In Chapters 2-15 (Fischer & Rahelivololona 2002, 2003, 2004, 2007, 2015a, 2015b, 2015c, 2016, Fischer et al. 2004. 2017, 2018a, b submitted, Rahelivololona et al. 2003) I presented the first results of a revision of Balsaminaceae of Madagascar and the Comoro islands including the description of 78 new species. In Chapter 16 (Yuan et al. 2004) we worked on the phylogeny and biogeography of Balsaminaceae inferred from ITS sequences using combined results from molecular phylogenetic and morphological analyses. In Chapter 17 (Rahelivololona et al. 2018) we conducted a phylogeny and assessment of the infrageneric classification of species in the Malagasy Impatiens (Balsaminaceae) with a particular emphasis on taxa collected from Marojejy.
Below I summarise the most important findings of each chapter and provide an outlook for future studies.
How many species of Impatiens occur in Madagascar and the Comoro islands?
To provide additional information on the taxonomic revision of Impatiens in Madagascar and the Comoro islands, the identification of already described species as well as the description of new species was conducted. Based on herbarium specimens from BR, G, K, NEU, P, TAN and on living plants collected during several field trips, 78 new species and 6 nomina nova have been published and another 70 new taxa are already identified. Actually more than 260 species occur in Madagascar and the Comoro islands and all of them are endemic. For each species, a description of the morphology, phenology, ecology and known distribution range was provided. Apart from new taxa, the delimitation of already described species like Impatiens firmula Baker and Impatiens hildebrandtii Baill. could be clarified by studying the types and by observing the variability in the field.
Are the groups of Impatiens in Madagascar monophyletic, and what is the systematic position of Trimorphopetalum?
Yuan & al. (2004) conducted a molecular phylogenetic study to examine the morphological and karyological evolution, and the historical biogeography of the Balsaminaceae family by using nucleotide sequence data of internal transcribed spacer regions of nuclear ribosomal DNA. The results support the monophyly of the Malagasy endemic section Trimorphopetalum and show that the cleistogamous Impatiens inaperta should be included in the sect. Trimorphopetalum which is the most derived within Impatiens. Therefore, the section Preimpatiens proposed by Perrier de la Bâthie (1934) is paraphyletic.
Rahelivololona & al. (2018) provided a phylogenetic study focused on three subdivisions (based on macromorphological characters) proposed by Perrier de la Bâthie (1934). The analysis was done using two nuclear AP3/DEF homologues (ImpDEF1 and ImpDEF2) and the plastid atpB-rbcL spacer to reassess or assess the monophyly of the Malagasy Impatiens, of the sections Preimpatiens (Humblotianae and Vulgare groups) and Trimorphopetalum. A focus was on the species of Impatiens from the Marojejy National Park and of the morphologically variable species I. elatostemmoides, I. “hammarbyoides”, I. inaperta and I. manaharensis, using monophyly as the primary criterion.
As results the Malagasy Impatiens are paraphyletic and the section Preimpatiens sensu Perrier de la Bâthie (1934) (= subgen. Impatiens sensu Fischer & Rahelivololona 2002) was not resolved as a monophyletic group. The section Trimorphopetalum sensu Perrier de la Bâthie (1934) (= subgen. Trimorphopetalum sensu Fischer & Rahelivololona 2002), however, was strongly confirmed as a monophyletic lineage (BS: 92; BPP: 1). Neither the Humblotianae group nor the Vulgare group was supported as monophyletic. None of the morphologically variable species appeared to be monophyletic and the sampled species of Impatiens from the Marojejy National Park do also not form a monophyletic group.
What are the biogeographical position and the distribution patterns of Impatiens in Madagascar and the Comoro islands?
Investigation of the geographical affinities and species distribution of section Impatiens (including Humblotianae group and Vulgare group) and section Trimorphopetalum were conducted and the origin and evolution as well as species richness and endemism were discussed.
The isolation, the climate and the complex topography of Madagascar have generated the microhabitats and ecological niches favourable to the diversification of Impatiens species. Impatiens of Madagascar with 260 endemic species is actually the largest genus in Madagascar. Therefore, Madagascar and the Comoro islands are among the most species-rich regions in the world for Impatiens.
Future studies
In Impatiens on Madagascar, there remain numerous unresolved questions that need to be adressed:
• A further study based on a much larger molecular data set and sampling from the entire geographic ranges of Impatiens in Madagascar is needed to retest the monophyly of the different subgenera and sections, as well as a molecular dating of the Malagasy Impatiens.
• The study of pollinators as a key for understanding the radiation and species richness is required: Within Impatiens the different shapes of spur are related to pollinators (bees, birds, butterflies and moths). Therefore pollinator observation of specific species need to be done to understand the radiation of species by adaptation and coevolution with these pollinators. A pollination study with a large number of species within section Trimorphopetalum will help to understand the mechanism of complete disappearance of the spur, the shift of pollinators and the evolution of species richness.
• The destruction of the natural habitats of Impatiens and the subsequent reduction of humidity in logged area constitute a severe threat for the survival of many species. The conservation and reforestation of vulnerable areas such as Ankaratra, Daraina, Mandraka and Col des Tapia near Antsirabe is required.
• In terms of conservation and to mitigate the threat on the genus, a study on the ex-situ-conservation of Malagasy Impatiens species is very important as long as some species are suitable for horticultural purposes (e.g. Impatiens mayae-valeriae, Impatiens emiliae and species with broad red spur).
• Finally, the publication of the revision of Impatiens of Madagascar and the Comoro islands will help other botanists to identify the species and will thus increase our knowledge on the group.
Lakes and reservoirs are important sources of methane, a potent greenhouse gas. Although freshwaters cover only a small fraction of the global surface, their contribution to global methane emission is significant and this is expected to increase, as a positive feedback to climate warming and exacerbated eutrophication. Yet, global estimates of methane emission from freshwaters are often based on point measurements that are spatio-temporally biased. To better constrain the uncertainties in quantifying methane fluxes from inland waters, a closer examination of the processes transporting methane from sediment to atmosphere is necessary. Among these processes, ebullition (bubbling) is an important transport pathway and is a primary source of uncertainty in quantifying methane emissions from freshwaters. This thesis aims to improve our understanding of ebullition in freshwaters by studying the processes of methane bubble formation, storage and release in aquatic sediments. The laboratory experiments demonstrate that aquatic sediments can store up to ~20% (volumetric content) gas and the storage capacity varies with sediment properties. The methane produced is stored as gas bubbles in sediment with minimal ebullition until the storage capacity is reached. Once the sediment void spaces are created by gas bubble formation, they are stable and available for future bubble storage and transport. Controlled water level drawdown experiments showed that the amounts of gas released from the sediment scaled with the total volume of sediment gas storage and correlated linearly to the drop in hydrostatic pressure. It was hypothesized that not only the timing of ebullition is controlled by sediment gas storage, but also the spatial distribution of ebullition. A newly developed freeze corer, capable of characterizing sediment gas content under in situ environments, enabled the possibility to test the hypothesis in a large subtropical lake (Lake Kinneret, Israel). The results showed that gas content was variable both vertically and horizontally in the lake sediment. Sediment methane production rate and sediment characteristics could explain these variabilities. The spatial distribution of ebullition generally was in a good agreement with the horizontal distribution of depth-averaged (surface 1 m) sediment gas content. While discrepancies were found between sediment depth-integrated methane production and the snapshot ebullition rate, they were consistent in a long term (multiyear average). These findings provide a solid basis for the future development of a process-based ebullition model. By coupling a sediment transport model with a sediment diagenetic model, general patterns of ebullition hotspots can be predicted at a system level and the uncertainties in ebullition flux measurements can be better constrained both on long-term (months to years) and short-term (minutes to hours) scales.
Small headwater streams comprise most of the total channel length and catchment area in fluvial networks. They are tightly connected to their catchments and, thus, are highly vulnerable to changes in catchment hydrologic budgets and land use. Although these small, often fishless streams are of little economic interest, they are vital for the ecological and chemical state of larger water bodies. Although numerous studies investigate the impact of various anthropogenic stressors or altered catchment conditions, we lack an in-depth understanding of the natural conditions and processes in headwater streams. This natural state, however, largely affects how a headwater stream responds to anthropogenic or climatic changes. One of the major threats to aquatic ecosystems is the excessive anthropogenic input of nutrients leading to eutrophication. Nutrients exert a bottom-up effect in the food web, foremost affecting primary producers and their consumers, i.e. periphyton and benthic grazers in headwater streams. The periphyton-grazer link is the main path of autochthonous (in-stream) production into the stream food web and the strength of this link largely determines the effectiveness of this pathway. Therefore, this thesis aims at elucidating important biological processes with the explicit focus on periphyton-grazer interactions. I assessed different aspects of periphyton-grazer interactions using laboratory experiments to solve methodological problems, and using a field study to compare the benthic communities of three morphologically similar, phosphorus-limited, near-natural headwater streams. With the results of the laboratory experiments, I was able to show that periphyton RNA/DNA ratios can be used as proxy for periphyton growth rates in controlled experiments and that the fatty acid composition of grazing mayfly nymphs responds to changes in fatty acids provided by the diet after only two weeks. The use of the RNA/DNA ratio as a proxy for periphyton growth rate allows a comparison of these growth rates even in simple experimental set-ups and thereby permits the inclusion of this important process in ecotoxicological or ecological experiments. The observed fast turnover rates of fatty acids in consumer tissues show that even short-term changes in available primary producers can alter the fatty acid composition of primary consumers with important implications for the supply of higher trophic levels with physiologically important polyunsaturated fatty acids. With the results of the field study, I revealed gaps in the understanding of the linkages between catchment and in-stream phosphorus availability under near-natural conditions and demonstrated that seemingly comparable headwater streams had significantly different benthic communities. These differences most likely affect stream responses to environmental changes.
Within the framework of a participatory action research approach, teachers and their students were accompanied scientifically with a focus on Montessori pedagogy and music in an upper secondary grammar school for three years (from 2012-2015).
Based on attitude- and self-efficacy-theories, inclusive instruction as well as agent-based research, the aim was to examine the implementation of an inclusive learning - and school-culture at this grammar school – an institution which is part of the highly selective education system at secondary II level in Austria.
It has been possible to reconstruct the understanding of teachers concerning inclusion and conceptions of man as well as their selfefficacy of competences to teach in an inclusive environment by means of qualitative and quantitative data. To examine attitudes and selfefficacy of teacher competences, international and national tested scales SACIE-R (Sentiments, Attitudes and Concerns about Inclusive Education-Revised) and TEIP (Teacher Efficacy for Inclusive Practice) were used in a German version. Furthermore, the empirical survey was extended by a webbased national questionnaire for teachers in different types of schools, from primary to secondary level (n= 427) to allow comparative analysis. Interviews, which were evaluated content-analytically and ques-tionnaires for parents (n=37) and students (n=19) offered an indepth insight into everyday educational practice from different perspectives.
The synopsis of the result shows, that it was possible for a rather young team of teachers with very positive attitudes towards inclusion, to implement a supportive and vivid learning - and school culture. Nevertheless, the efforts of the teachers did not exceed the system limits. The development towards a ‘school for all’, a logical consequence of theoretical approaches concerning inclusion, was not discovered. The current research is verifying the corefindings of inclusive - and agent-based research. Further findings can be related to the selective structures of the education system in secondary II.
Navigation is a natural way to explore and discover content in a digital environment. Hence, providers of online information systems such as Wikipedia---a free online encyclopedia---are interested in providing navigational support to their users. To this end, an essential task approached in this thesis is the analysis and modeling of navigational user behavior in information networks with the goal of paving the way for the improvement and maintenance of web-based systems. Using large-scale log data from Wikipedia, this thesis first studies information access by contrasting search and navigation as the two main information access paradigms on the Web. Second, this thesis validates and builds upon existing navigational hypotheses to introduce an adaptation of the well-known PageRank algorithm. This adaptation is an improvement of the standard PageRank random surfer navigation model that results in a more "reasonable surfer" by accounting for the visual position of links, the information network regions they lead to, and the textual similarity between the link source and target articles. Finally, using agent-based simulations, this thesis compares user models that have a different knowledge of the network topology in order to investigate the amount and type of network topological information needed for efficient navigation. An evaluation of agents' success on four different networks reveals that in order to navigate efficiently, users require only a small amount of high-quality knowledge of the network topology. Aside from the direct benefits to content ranking provided by the "reasonable surfer" version of PageRank, the empirical insights presented in this thesis may also have an impact on system design decisions and Wikipedia editor guidelines, i.e., for link placement and webpage layout.
Im Fokus der Arbeit steht die Frage des Kompetenzzuwachses in und durch außerunterrichtliche Sport- und Bewegungsangebote an rheinland pfälzischen Ganztagsschulen, die von Trainerinnen und Trainern angeboten und durchgeführt werden. Um dieser Fragestellung nachzugehen, wurden zunächst Schul- und Unterrichtsqualitätsmodelle auf das außerunterrichtlichen Sport- und Bewegungsangebot übertragen, um das zu untersuchende Setting im Kontext der rheinland-pfälzischen Ganztagsschullandschaft zu verorten und mögliche Einflussfaktoren und Wechselwirkungen vor dem Hintergrund des Kompetenzzuwachses der Teilnehmerinnen und -nehmer aufzuzeigen. Dem nachgestellt wurden während der Darlegung theoretischer Vorüberlegungen, wie z.B. Aspekte zum außerschulischen Bildungsverständnis und Sport und Bewegung in den Erziehungswissenschaften, Kategorien und Kriterien ermittelt, deren Nachweis den Kompetenzzuwachs der Schülerinnen und Schüler stark vermuten lassen. Die Untersuchungsleitlinie dieser Arbeit wurde ein qualitatives Forschungsdesign eingebunden. Die herangezogene Forschungsstrategie bildet eine vergleichende Fallanalyse. Als Erhebungsmethode dient das Experteninterview; ein problemorientiertes Interview im Übungsleiterinnen und -leitern, die für die Planung und Durchführung der in rheinland-pfälzischen Ganztagsschulen implementierten Sport- und Bewegungsangebote verantwortlich zeichnen. Die Auswertung erfolgte über eine modifizierte Form der qualitativen Inhaltsanalyse. In der Summe konnte aufgezeigt werden, dass es sich bei den untersuchten Sport- und Bewegungsangeboten um hochwertige Settings handelt, in denen Kriterien und hypothetische Annahmen aus den Schul- und Unterrichtsqualitätsmodellen aufgezeigt werden konnten und somit günstige Voraussetzungen –die aktive Teilnahme vorausgesetzt– für den Kompetenzerwerb der Schülerinnen und Schüler an Ganztagsschulen vorliegen.
Technologische Fortschritte auf dem Gebiet der integrierten Halbleitertechnik, die unter anderem auch zur gestiegenen Leistungsfähigkeit der Kamerasensoren beitragen, konzentrierten sich bisher primär auf die Schnelligkeit und das Auflösungsvermögen der Sensoren. Die sich ständig verändernde Entwicklung hat jedoch direkte Folgen auf das physikalische Verhalten einer Kamera und damit auch Konsequenzen für die erreichbare geometrische Genauigkeit einer photogrammetrischen 3D-Rekonstruktion. Letztere stand bisher nicht im Fokus der Forschung und ist eine Aufgabe, der sich diese Arbeit im Sinne der Photogrammetrie und Messtechnik stellt. Aktuelle Untersuchungen und Erfahrungen aus industriellen Projekten zeigen in diesem Zusammenhang, dass das geometrisch-physikalische Verhalten digitaler Kameras - für höchste photogrammetrische Ansprüche - noch nicht ausreichend modelliert ist. Direkte Aussagen zur erreichbaren Genauigkeit bei gegebener Hardware erweisen sich daher bislang als unzureichend. Ferner kommt es aufgrund der unpräzisen Modellierung zu Einbußen in der Zuverlässigkeit der erreichten Ergebnisse. Für den Entwickler präziser kamerabasierter Messverfahren folgt daraus, dass zu einer optimalen Schätzung der geometrischen Genauigkeit und damit auch vollständigen Ausschöpfung der Messkamera geeignete mathematische Modelle erforderlich sind, die das geometrisch physikalische Verhalten bestmöglich beschreiben. Diese Arbeit beschreibt, wie die erreichbare Genauigkeit einer Bündelblockausgleichung, schon a priori mithilfe des EMVA1288 Standards approximiert werden kann. Eine in diesem Zusammenhang wichtige Teilaufgabe ist die Schaffung einer optimalen Messanordnung. Hierzu gehören Untersuchungen der üblicherweise verwendeten Kalibrierkörper und die Beseitigung von systematischen Fehlern vor und nach der Bündelblockausgleichung. Zum Nachweis dieser Systematiken wird eine auf statistischem Lernen basierende Methode beschrieben und untersucht. Erst wenn alle genauigkeitsmindernden Einflüsse berücksichtigt sind, wird der Anteil des Sensors in den Messdaten sichtbar und damit auch mathematisch parametrisierbar. Die Beschreibung des Sensoreinflusses auf die erreichbare Genauigkeit der Bündelblockausgleichung erfolgt in drei Schritten. Der erste Schritt beschreibt den Zusammenhang zwischen ausgewählten EMVA1288-Kennzahlen und der Unsicherheit eines Grauwertes. Der zweite Schritt ist eine Modellierung dieser Grauwertunsicherheit als Zentrumsunsicherheit einer Zielmarke. Zur Beschreibung dieser Unsicherheit innerhalb der Bündelblockausgleichung wird ein stochastisches Modell, basierend auf dem EMVA1288-Standard, vorgeschlagen. Ausgehend vom Rauschen des Zielmarkenmittelpunktes wird im dritten Schritt die Unsicherheit im Objektraum beispielhaft mit Hilfe von physikalisch orientierten Simulationen approximiert. Die Wirkung der vorgeschlagenen Methoden wird anhand von Realkalibrierungen nachgewiesen. Abschließend erfolgt die Diskussion der vorgeschlagenen Methoden und erreichten Ergebnisse sowie ein Ausblick auf kommende Untersuchungen.
The cytological examination of bone marrow serves as clarification of variations in blood smears. It is also used for the clarification of anemia, as exclusion of bone marrow affection at lymphoma and at suspicion of leukemia. The morphological evaluation of hematopoietic cells is the basis for the creation of the diagnosis and for decision support for further diagnostics. Even for experienced hematologists the manual classification of hematopoietic cells is time-consuming, error-prone and subjective. For this reason new methods in the field of image processing and pattern recognition for the automatic classification including preprocessing steps are developed for a computer-assisted microscopy system. These methods are evaluated by means of a huge reference database. The proposed image analysis procedures comprise methods for the automated detection of smears, for the determination of relevant regions, for the localization and segmentation of single hematopoietic cells as well as for the feature extraction and classification task. These methods provide the basis for the first system for the automated, morphological analysis of bone marrow aspirates for leukemia diagnosis and are therefore a major contribution for a better and more efficient patient care in the future.
Retrospektive Analyse der Ausbreitung und dynamische Erkennung von Web-Tracking durch Sandboxing
(2018)
Aktuelle quantitative Analysen von Web-Tracking bieten keinen umfassenden Überblick über dessen Entstehung, Ausbreitung und Entwicklung. Diese Arbeit ermöglicht durch Auswertung archivierter Webseiten eine rückblickende Erfassung der Entstehungsgeschichte des Web-Trackings zwischen den Jahren 2000 und 2015. Zu diesem Zweck wurde ein geeignetes Werkzeug entworfen, implementiert, evaluiert und zur Analyse von 10000 Webseiten eingesetzt. Während im Jahr 2005 durchschnittlich 1,17 Ressourcen von Drittparteien eingebettet wurden, zeigt sich ein Anstieg auf 6,61 in den darauffolgenden 10 Jahren. Netzwerkdiagramme visualisieren den Trend zu einer monopolisierten Netzstruktur, in der bereits ein einzelnes Unternehmen 80 % der Internetnutzung überwachen kann.
Trotz vielfältiger Versuche, dieser Entwicklung durch technische Maßnahmen entgegenzuwirken, erweisen sich nur wenige Selbst- und Systemschutzmaßnahmen als wirkungsvoll. Diese gehen häufig mit einem Verlust der Funktionsfähigkeit einer Webseite oder mit einer Einschränkung der Nutzbarkeit des Browsers einher. Mit der vorgestellten Studie wird belegt, dass rechtliche Vorschriften ebenfalls keinen hinreichenden Schutz bieten. An Webauftritten von Bildungseinrichtungen werden Mängel bei Erfüllung der datenschutzrechtlichen Pflichten festgestellt. Diese zeigen sich durch fehlende, fehlerhafte oder unvollständige Datenschutzerklärungen, deren Bereitstellung zu den Informationspflichten eines Diensteanbieters gehören.
Die alleinige Berücksichtigung klassischer Tracker ist nicht ausreichend, wie mit einer weiteren Studie nachgewiesen wird. Durch die offene Bereitstellung funktionaler Webseitenbestandteile kann ein Tracking-Unternehmen die Abdeckung von 38 % auf 61 % erhöhen. Diese Situation wird durch Messungen von Webseiten aus dem Gesundheitswesen belegt und aus technischer sowie rechtlicher Perspektive bewertet.
Bestehende systemische Werkzeuge zum Erfassen von Web-Tracking verwenden für ihre Messung die Schnittstellen der Browser. In der vorliegenden Arbeit wird mit DisTrack ein Framework zur Web-Tracking-Analyse vorgestellt, welches eine Sandbox-basierte Messmethodik verfolgt. Dies ist eine Vorgehensweise, die in der dynamischen Schadsoftwareanalyse erfolgreich eingesetzt wird und sich auf das Erkennen von Seiteneffekten auf das umliegende System spezialisiert. Durch diese Verhaltensanalyse, die unabhängig von den Schnittstellen des Browsers operiert, wird eine ganzheitliche Untersuchung des Browsers ermöglicht. Auf diese Weise können systemische Schwachstellen im Browser aufgezeigt werden, die für speicherbasierte Web-Tracking-Verfahren nutzbar sind.
Changing Lives through Relocation - Ethnography of a Socialized Housing Project in the Philippines
(2018)
Changing lives through relocation - This is the vision of a socialized housing project in the Philippines which is subject of this dissertation. It is a polyphonic ethnography that investigates the transition process from an informal, marginalized, self-organized lifestyle in squatter areas and dumpsite settlements to an institutionalized and policy-based life in the socialized housing project. The transition process is analyzed from a material cultural perspective taking into account selected aesthetic theories. With this approach, the dissertation aims to contribute to the study of the aesthetic dimension of everyday life from an ethnographic perspective. Aesthetics are applied on three levels: (1) On the theoretical level, the concepts of social aesthetics and atmospheres enrich the analysis of the interrelation between the residents and their new house in the socialized housing project. (2) On the methodological level, the relevance of aesthetic experiences for the ethnographic knowledge process are discussed. And (3) on the descriptive level, selected and thematically relevant sensory and aesthetic experiences of the researcher inform the ethnographic account in the form of memoirs. By incorporating aesthetic theories, the dissertation gives a more holistic account of the dynamics active in the transition process. It shows that the change of lifestyle is experienced sensorily through the daily physical engagement with the new material environment, i.e. its specific materiality and infrastructure, its affordances and constraints giving rise to new experiences and needs. In this process, the residents become aware of the differences between the past and present way of life and thus experience the new challenges through their physical being in the new material environment. On the one hand, this evokes a nostalgic attitude towards their previous life, but on the other hand, it also gives form to ideas of a possible future.
Maßnahmen der Führungskräfteentwicklung verfolgen das Ziel den Führungsnachwuchs des Unternehmens zu bilden und für einen reibungslosen Einstieg in die Füh-rungsaufgabe zu sorgen. In der Literatur gibt es zahlreiche Theorien und Modelle zu Führung und deren Entwicklung, doch offen bleibt meist, wie es um den praktischen Einsatz und die Effektivität steht. Das Ziel dieser Arbeit ist die Identifikation wesentlicher Bestandteile der Führungskräfteentwicklung, die effektiv Einfluss auf (Nachwuchs-)Führungskräfte nehmen. Drei Studien beschäftigen sich jeweils mit unter-schiedlichen Schwerpunkten mit der Gestaltung und Wirksamkeit von modularen Programmen der Führungskräfteentwicklung. Zur Beschreibung der Gestaltung wurde eine Expertenbefragung unter Verantwortlichen für Führungskräfteentwicklung in 4 Großunternehmen durchgeführt. Zur Prüfung der Wirksamkeit wurden zwei Prädiktoren erfolgreichen Führens, die praktische Führungsintelligenz und die Führungswirksamkeitserwartung (FWE), in zwei repräsentativen modularen Programmen gemessen. Dafür wurden zwei quasiexperimentelle Designs mit Prätest-Posttest durchgeführt: ein Design mit zusätzlicher Kontrollgruppe (Nexp = 14, Nkontr = 12), ein Design mit zusätzlicher Fremdeinschätzung (N = 11 bis N =57 je nach Messzeitpunkt und beteiligten Variablen). Die praktische Führungsintelligenz wurde anhand eines für die Untersuchung entwickelten Situational Judgment Tests (SJTs) gemessen. Neben der FWE (in Anlehnung an die Skala zur Erfassung der beruflichen Selbstwirksamkeitserwartung, BSW-Skala) wurden weitere Konstrukte wie Selbstregulation (Locomotion-Assessment-Fragebogen, L-A-F), Optimismus (Skala Optimismus-Pessimismus-2, SOP2) Selbstmanagement (Fragebogens zur Erfassung von Ressourcen und Selbstmanagementfähigkeiten, FERUS) erfasst, sowie explorativ entwicklungsförderliche Merkmale erhoben. Entsprechend der Annahme verdichten sich die Ergebnisse auf drei Merkmale wirksamer Trainingsgestaltung: Erfahrungssammlung, Feedback, Selbstreflexion. Es konnte nachgewiesen werden, dass Programme mit hohem erfahrungsorientiertem Trainingsanteil, die Erfolgserlebnisse und Modelllernen fördern sowie persönliche Gespräche und Feedback beinhalten, die FWE (ŋ2 = .24, ŋ2 = .50) und die praktische Führungsintelligenz (ŋ2 = .54). signifikant (p<.05) steigern. Deutlich wurde auch der enge Zusammenhang zwischen Merkmalen der Person (wie Ausprägung der FWE oder Selbstregulationsfähigkeiten) und der Wirksamkeit der Programme. Aus den Ergebnissen werden Empfehlungen zur praktischen Umsetzung in der Führungskräfteentwicklung abgeleitet und Anregungen für zukünftige Forschung diskutiert.
The concept of hard and soft news (HSN) is regarded as one of the most important concepts in journalism research. Despites this popularity, two major research voids can be assigned to the concept. First, it lacks conceptual clarity: the concept gets used interchangeably with related concepts such as sensationalism, which has led to fuzzy demarcations of HSN. Also, it is still not agreed on of which dimensions the concept in composed. Second, little is known about the factors that influence the production of news in terms of their hard or soft nature. The present disserta-tion casts a twofold glance on the HSN concept – it aims to assess the conceptual status of the concept and production of hard and soft news.
At the outset, this dissertation delineates the theoretical base for three manuscripts in total and presented considerations on concepts in social sciences in general and hard and soft news in particular as well as the production of news, particularly of hard and soft news. The first paper proposed a theoretical frame-work model to distinguish HSN and related concepts. Based on a literature review of in total five concepts, this model suggested a hierarchy in which these concepts can be discerned according to their occurrence in media content. The second pa-per focused on the inner coherence of the HSN concept in its most recent academ-ic understanding. The results of a factorial survey with German newspaper jour-nalists showed that, indeed, four out of five dimensions of the HSN concept com-prised what the journalists understood by it. Hence, the most recent academic un-derstanding is to a great extent coherent. The third study shed light on the produc-tion of HSN, focusing on the influence of individual journalists’ and audience’s characteristics on whether news was presented in hard or soft way. The findings of a survey with simulated decision scenarios among German print journalists showed that the HSN dimensions were susceptible to different journalistic influ-ences and that a perceived politically uninterested audience led to a softer cover-age. The dissertation concluded with connecting these findings with the considera-tions on concept evaluation and the production of news. Implications for research on and with the concept of HSN were presented, before concluding with limitations and suggestions for future research.