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Despite the great progress that has been made in the prophylaxis of oral diseases over the past decades, dental caries and periodontal diseases remain major challenges in the field of dentistry. Biofilm formation on dental hard tissues is strongly associated with the etiology of these oral diseases. Therefore, the process of bioadhesion and biofilm formation on tooth surfaces is of particular interest for dental research. The first stage of bioadhesion on dental surfaces is the formation of the pellicle layer. This mainly acellular film, composed largely of adsorbed proteins, glycoproteins, and lipids, is distinguished from the microbial biofilm (plaque). As the interface between teeth and the oral environment, the pellicle plays a key role in the maintenance of oral health and is of great physiological and pathophysiological importance. On the one hand, the pellicle shows protective properties for the underlying dental hard tissues. On the other hand, it also serves as the basis for dental plaque and therefore, for the development of oral diseases such as caries and periodontitis. Hydrophobic interactions, which are governed by lipophilic substances, are of high relevance for bacterial adherence. Therefore, pellicle lipids, which are a significant constituent of this biological structure, are an interesting target for dental research, as they could modulate oral surfaces, influence microbial interactions, and potentially impede bacterial adherence. Compared to the extensive work on the pellicle´s ultrastructure and protein/amino acid composition, little attention has been given to its lipid profile. Knowledge of the lipid composition of the pellicle may provide insight into several oral pathological states, including caries, dental erosion, and periodontal disease processes and could contribute to novel approaches in preventive dentistry. The principle aim of this thesis was the comprehensive characterization of the fatty acid (FA) profile of the in situ formed pellicle layer. This includes the influence of pellicle maturation on the FA profile as well as intra- and interindividual differences. Furthermore, investigations on the effect of rinses with edible oils on the pellicle´s FA composition were a focus of this work. For these purposes, an analytical method based on a combination of innovative specimen generation and convenient sample preparation with sensitive mass spectrometric analysis was successfully developed and comprehensively validated within this thesis. Pellicle samples were formed in situ on bovine enamel slabs mounted on individual upper jaw splints. After a comprehensive sample preparation, gas chromatography coupled with electron impact ionization mass spectrometry (GC-EI/MS) was used in order to characterize qualitatively and quantitatively a wide range of FA (C12-C24). The individual FA profiles of pellicle and saliva samples collected from ten research participants were investigated. The relative FA profiles of the pellicle samples gained from the different subjects were very similar, whereas the amount of FAs showed significant interindividual variability. Compared to the pellicle´s characteristic FA profile, higher proportions of unsaturated FAs were detected in the saliva samples, highlighting that FAs available in saliva are not adsorbed equivalently to the pellicle layer. This, in turn, shows that pellicle formation is a highly selective process that does not correlate directly with salivary composition. Additionally, pellicle samples collected after 3, 30, 60, 120, and 240 min of intraoral exposure were analyzed. It could be shown that pellicle maturation has only a minor impact on the FA composition. However, the FA content increased substantially with increasing oral exposure time. Modifying the pellicle´s lipid composition by using edible oils as a mouthwash could alter the physicochemical characteristics of the pellicle and strengthen its protective properties by delaying bacterial adhesion. Therefore, the impact of rinses with safflower oil on the pellicle´s FA composition was determined. The application of rinses with safflower oil resulted in an accumulation of its specific FAs in the pellicle, thus representing a possibility for modifying the pellicle´s lipid profile. The present work is the first to apply a validated method that combines in situ pellicle formation, sample preparation, and the comprehensive determination of FAs via a sensitive analytical method. The results provide valuable information regarding the pellicle´s FA composition which closes an existing knowledge gap in pellicle research. A broader knowledge of the lipid composition of the pellicle contributes to the understanding of oral bioadhesion processes and may help facilitate novel approaches in preventive dentistry.
Eine steigende Zahl älterer Menschen lebt in Deutschland im Zustand der Altersarmut oder ist von Altersarmut bedroht. Die Klärung von Dimensionen der Altersarmut in Deutschland steht im Zentrum der Dissertation. Anhand der Gerechtigkeitstheorie von Martha C. Nussbaum, dem Capability Approach, lassen sich globale Dimensionen von (Alters-)Armut ermitteln. Die Altersarmutswirklichkeit in Deutschland wird durch die christliche Sozialethik beschrieben und die globalen Armutsdimensionen werden in den bundesdeutschen Armutskontext gesetzt. Aus den ermittelten Grundlagen zur Altersarmut in Deutschland ergibt sich eine erste ganzheitliche Definition des Begriffs ‚Altersarmut’. Dieser Begriffsentwurf soll einer wissenschaftlichen, interdisziplinären Diskussion ausgesetzt werden. Die Ergebnisse der Forschungsarbeit ermöglichen Handlungsempfehlungen für Gesellschaft, Staat, Soziale Arbeit und die Menschen, die zum Abbau, zur Vermeidung und zur Bewältigung von Altersarmutszuständen beitragen können.
Depressionen spielen eine gewichtige Rolle im Forschungsfeld der mentalen Gesundheit. Durch eine zunehmende Digitalisierung erscheint es naheliegend, depressive Störungen auch mithilfe internetbasierter Maßnahmen zu behandeln. Für den effektiven Einsatz internetbasierter interventionen existiert bereits vielfältige Evidenz. Bisher gibt es allerdings nur begrenzte Erkenntnisse darüber, ob internetbasierte Maßnahmen zur Behandlung von majoren Depressionen auch aktiven Kontrollbedingungen überlegen sind. Die Ergebnisse einer randomisiert-kontrollierten Studie (RCT = randomized controlled trial) zum Vergleich einer internetbasierten Intervention mit reiner Online-Psychoedukation (Studie 1) zeigen, dass dies zutrifft. Darüber hinaus ist die Erkenntnislage für Personen mit subklinischen depressiven Symptomen hinsichtlich ihrer langfristigen Wirksamkeit inkonsistent. Eine Meta-Analyse auf Basis der individuellen Teilnehmerdaten (IPD-MA = individual participant data meta-analysis) zur Evaluation der Wirksamkeit internetbasierter Maßnahmen zur Behandlung von subklinischen depressiven Symptomen (Studie 2) führte zu einer kurz-, mittel- und langfristigen Überlegenheit der Behandlungsgruppe im Vergleich zur Kontrollgruppe. Eine zusätzliche Analyse ergab, dass das Risiko für die Entwicklung einer majoren Depression innerhalb von 12 Monaten in der Interventionsgruppe im Vergleich zur Kontrollgruppe 28 % geringer ist. Für die Implementierung internetbasierter Maßnahmen in die Routineversorgung ist es gegebenenfalls erforderlich, geeignete Maßnahmen zu ergreifen, um mit den Studienergebnissen vergleichbar hohe Effekte bei den Betroffenen zu erreichen. Die Identifizierung von Faktoren, die den Behandlungserfolg beeinflussen, ist von großem Interesse, um internetbasierte Maßnahmen geeigneten Populationen kosteneffektiv und mit maximalem Nutzen zur Verfügung stellen zu können. Die IPD-MA für Personen mit subklinischen Symptomen (Studie 2) zeigte, dass eine hohe initiale Symptomschwere und höheres Alter zu einer niedrigeren depressiven Symptomatik zum Post-Messzeitpunkt führten. Eine weitere IPD-MA für Personen mit majorer Depression (Studie 3) identifizierte darüber hinaus ein geringes Bildungsniveau als Risikofaktor für eine Symptomverschlechterung. Die Ergebnisse des RCT (Studie 1) lassen vermuten, dass für Teilnehmer mit vorangehender Psychotherapieerfahrung Online-Psychoedukation bereits hilfreich ist, während diese Maßnahme für Therapie-Neulinge keinen Nutzen zeigt, sie aber erheblich von der internetbasierten Intervention zur Behandlung ihrer Symptome profitieren. Angesichts der zunehmenden Nutzung internetbasierter Maßnahmen zur Behandlung von depressiven Symptomen erscheint es erforderlich, das Augenmerk neben dem Behandlungsnutzen auch auf die unerwünschten Nebenwirkungen zu lenken, für deren Berichterstattung und Handhabung es in diesem Forschungsfeld bisher kaum einen Konsens gibt. Die IPD-MA zur Behandlung von majoren Depressionen (Studie 3) konnte zeigen, dass das Risiko für eine reliable Verschlechterung von der Ausgangssituation bis zum Post-Messzeitpunkt in der Interventionsgruppe im Vergleich zur Kontrollgruppe signifikant geringer war. Eine langfristige Überlegenheit ließ sich nicht konsistent bestätigen. Der RCT (Studie 1) zeigte keinen signifikanten Unterschied in den Verschlechterungsraten zwischen den beiden Versuchsgruppen. In Studie 2 war die Interventionsgruppe der Kontrollgruppe zum Post-Messzeitpunkt und nach 12 Monaten hinsichtlich einer Symptomsteigerung um 50 % überlegen. Wie negative Effekte von internetbasierten Maßnahmen zukünftig idealerweise definiert und berichtet werden sollten, bedarf weiterer Klärung.
Wind energy is expected to become the largest source of electricity generation in Europe's future energy mix. As a consequence, future electricity generation will be exposed to an increasing degree to weather and climate. With planning and operational lifetimes of wind energy infrastructure reaching climate time scales, adaptation to changing climate conditions is of relevance to support secure and sustainable energy supply. Premise for success of wind energy projects is the ability to service financial obligations over the project lifetime. Though, revenues(viaelectricity generation) are exposed to changing climate conditions affecting the wind resource, operating conditions or hazardous events interfering with the wind energy infrastructure. For the first time, a procedure is presented to assess such climate change impacts specifically for wind energy financing. At first, a generalised financing chain for wind energy is prepared to (qualitatively) trace the exposure of individual cost elements to physical climate change. In this regard, the revenue through wind power production is identified as the essential component within wind energy financing being exposed to changing climate conditions. This implies the wind resource to be of crucial interest for an assessment of climate change impacts on the financing of wind energy. Therefore, secondly, a novel high-resolution experimental modelling framework with the non-hydrostatic extension of the regional climate model REMO is set up to generate physically consistent climate and climate change information of the wind resource across wind turbine operating altitudes. With this setup, enhanced simulated intra-annual and inter-annual variability across the lower planetary boundary layer is achieved, being beneficial for wind energy applications, compared to state-of-the-art regional climate model configurations. In addition, surrogate climate change experiments with this setup disclose vertical wind speed changes in the lower planetary boundary layer to be indirectly affected by temperature changes through thermodynamically-induced atmospheric stability alterations. Moreover, air density changes are identified to occasionally exceed the net impact of wind energy density changes originating from changes in wind speed. This supports the consideration of air density information (in addition to wind speed) for wind energy yiel assumptions. Thirdly, the generated climate and climate change information of the wind resource are transferred to a simplified but fully-fledged financial model to assess the financial risk of wind energy project financing with respect to changing climate conditions. Sensitivity experiments for an imaginary offshore wind farm located in the German Bight reveal the long-term profitability of wind energy project financing not to be substantially affected by changing wind resource conditions, but incidents with insufficient servicing of financial obligations experience changes exceeding -10% to 14%. The integration of wind energy-specific climate and climate change information into existing financial risk assessment procedures would illustrate a valuable contribution to enable climate change adaptation for wind energy.
In Zeiten des technologischen, wirtschaftlichen, gesellschaftlichen und demographischen Wandels, zunehmenden internationalen Wettbewerbs und des daraus resultierenden Veränderungs- und Innovationsdrucks für Unternehmen, ist das psychologische Band zwischen Organisation und Mit-arbeiter vielfältigen Belastungen ausgesetzt. Längst ist es nicht mehr selbstverständlich, dass Mitarbeiter ihr gesamtes Arbeitsleben in einem Unternehmen verbringen. Gleichzeitig ist es für den Erfolg von Unternehmen von großer Bedeutung, qualifizierte und engagierte Mitarbeiter an sich zu binden. Organisationale Identifikation und affektives Commitment beschreiben Formen emotionaler Bindung von Mitarbeitern an ihr Unternehmen, die zu hoher Leistung und freiwilligem Engagement motivieren. Die vorliegende Arbeit beschäftigt sich mit der Frage nach stabilen interpersonalen Unterschieden, die das Bedürfnis und die Fähigkeit zur sozialen Identifikation und emotionalen Verbundenheit mit Organisationen grundsätzlich determinieren. Zentral ist die Annahme, dass die soziale Orientierung von Mitarbeitern ihre Bindungs- und Identifikationsbereitschaft erheblich beeinflusst: Das Ausmaß von kollektivistischer und individualistischer Orientierung sollte die Erwartungen, das Erleben und Verhalten von Mitarbeitern in Organisationen erheblich mitprägen. Für Menschen mit ausgeprägt kollektivistischer Orientierung wird ein starkes Bedürfnis nach Gruppenzugehörigkeiten zur Ableitung sozialer Identität unterstellt. Die Mitgliedschaft in der Gruppe, ihre Merkmale und Erfolge sollten selbstbeschreibend wirken und das persönliche Verhalten stark an den Interessen und Normen der Gruppe orientiert sein. Bei Menschen mit ausgeprägt individualistischer Orientierung werden demgegenüber persönliche Merkmale, Eigenschaften und Leistungen als zentral für die Selbstbewertung und Selbstdefinition angenommen. Gruppenzugehörigkeiten werden als relativ austauschbare Bezugsrahmen für das eigene Handeln und die Erreichung persönlicher Ziele erwartet. Der Arbeit liegt die Annahme zugrunde, dass die Entstehung und Ausprägung von Commitment und Identifikation in Abhängigkeit von der sozialen Orientierung der Mitarbeiter variiert. Mitarbeiter mit stärker kollektivistischer Orientierung sollten eine größere Bereitschaft haben, sich mit ihrer Organi-sation und Arbeitsgruppe zu identifizieren. Die Entstehung von affektivem Commitment und Identifikation sollte dabei primär von Faktoren geprägt werden, die die Befriedigung ihres Bedürfnisses nach sozialer Zugehörigkeit und Anerkennung fördern, wie z.B. die Beziehung zu Vorge-setzten und Kollegen. Die emotionale Bindung und Identifikation von Mitarbeitern mit stärker individualistischer Orientierung wird demgegenüber als geringer ausprägt erwartet. Bei diesen sollte die kalkulatorische Bindung an das Unternehmen überwiegen. Anders als bei stärker kollektivistisch orientierten Mitarbeitern sollten vor allem die Möglichkeiten der Karriere und Weiterbildung sowie die Qualität der Arbeitsinhalte (Interessantheit, Eigenverantwortung, Herausforderung) eine gewichtige Rolle für das Ausmaß der emotionalen Verbundenheit spielen. Zur Untersuchung der vermuteten Zusammenhänge wurde im Jahr 2006 in einem namhaften Industrieunternehmen eine Fragebogenstudie durchgeführt, an der sich 499 Mitarbeiter beteiligten. Obwohl die Unterschiede zwischen „Kollektivisten“ (N = 154) und „Individualisten“ (N = 151) weniger deutlich ausfallen als erwartet, erweist sich ihre Beziehung zum Unternehmen doch als different. Bei den Individualisten überwiegt die kalkulatorische Bindung an die Organisation erwartungs-konform gegenüber der emotionalen Verbundenheit. Individualisten erscheinen, trotz grundsätz-licher Zufriedenheit und einer gewissen emotionalen Gebundenheit, als relativ autonom und bei attraktiven Alternativen geneigt, das Unternehmen zu wechseln. Eine übermäßige Verbundenheit mit der persönlichen Karriere kann nicht bestätigt werden. Bei den Kollektivisten erweist sich hypothesenkonform die Beziehung zu Organisation und Arbeits-gruppe als von tiefgehend emotionaler Natur, der das Karriere-Commitment nachgeordnet ist. Auch deuten sich in den Regressionsanalysen Unterschiede in den Entstehungsbedingungen der betrachteten Foci an, die ebenfalls einen signifikanten Einfluss der sozialen Orientierung nahelegen und zu weitergehenden Analysen ermutigen.
Fostering socio-economic development throughout all Member States is a fundamental goal of the European Union. With one third of its budget, the EU tries to support regional development in lessdeveloped regions and improve the life of its citizens. To reach its goal, a shift can be observed from a single sided focus on factor mobility and thus transportation and other infrastructure facilities to a higher diversity in approaches, including culture, the arts and creativity. Here, creative industries and innovation are keywords within Structural Funds, the main instrument of EU regional policies. However, very little is known on how cultural operators in the form of artists, opera houses etc. contribute to regional development by implementing Structural Funds projects. The framework conditions set on EU level are very open, allowing the sector to contribute in their own way to socioeconomic development. To improve the understanding of how cultural operators access Structural Funds this dissertation was guided by the question: What kind of strategies do cultural operators use to access Structural Funds in Poland? Or on a more abstract level: What are the formal and informal norms within the application process for cultural operators, and in which way do they impact the application strategies of cultural operators in Poland? By working on those questions, this dissertation is providing an insight into how cultural operators on the ground approach Structural Funds. The case study on cultural operators in Poland serves as a concrete example and gives a clearer picture of access strategies, barriers and facilitators within this process. Because research is scarce on this subject, a choice for an in-depth case study analysis within one country was taken. With a theoretical framework of sociological Neo Institutionalism, especially a model developed by Victor Nee and Paul Ingram (1998), the research focusses on different levels of interaction and the role of formal and informal norms. The model was modified to support the analysis of actors’ strategies, and explain the application process of cultural operators. Here, the focus was on the micro level (cultural operators) and its interaction with the meso level (national). The model was enriched at the end of the research with elements of Bourdieu’s theory of practise, namely his concepts of fields and capital. Poland was selected as case study country due to its unique position as the biggest new Member State with its long cultural tradition at the heart of Europe and a very positive formal framework for cultural projects within Structural Funds. The focus was on the years 2004-2007 and thus covered mainly the first funding period for Poland. As empirical evidence, 27 expert interviews were carried out with cultural operators and their environment in Poland. They were analysed on a qualitative basis, using Atlas.ti, and co-occurrence network views. The author conducted all interviews within a period of two months, and most of the interviews were conducted in English. Important steps within the analysis were the emergence of a project idea, the ‘melting’ of this idea into a project application, different challenges linked to the application process and information gathering as a crucial factor within this process. In the end, the findings were validated by three EU experts from the Commission and the European Parliament. Conclusions: Findings show that the application strategy is driven by a set of formal and informal norms. Among them one can find elements linked to financing and co-financing, access and distribution of information and capacity building in the form of knowledge gathering and experience. The informal channels proved to be especially valuable. Further, the organisation resources have a significant impact when applying for Structural Funds. This is not limited to sufficient financial means but also related to existing networks and knowledge of whom to ask for information and support. Here, reference can be made e.g. to Bourdieu’s concept of capitals. Based on those findings, a typology of three different actors’ groups with different challenges and project profiles was developed. It can be shown that their positions and strategies are influenced, not only by formal rules and norms, but also to a high level, by informal norms and structures. As a result, projects were generally implemented by rather big and well-established organisations. Most of them focussed on the conservation of cultural heritage or the construction of new, ‘classical’ cultural infrastructure such as museums and opera houses. However, innovation and creativity are thought to grow especially in smaller, often younger and ‘different’ settings. As the EU is interested in those elements to find a region-tailored solution to socio-economic development needs, a nearly exclusive focus on rather traditional flagship projects implemented by well-established organisations appears insufficient: In other words, there is a discrepancy between proclaimed possibilities and attempts within political statements and Structural Funds rules on one side and the picture on the ground on the other side. Thus, if the fostering of socio-economic development through innovation and new approaches is to emerge, attempts need to be taken to increasingly support cultural operators with less favourable given capital. The thesis presented enhances knowledge within these processes and therefore contributes to the improvement of the situation. Because only if conditions are analysed and known, processes on national and EU level can change and alternatives be considered. As a conclusion for the micro level, a strong networking and gathering of know-how independently from formal structures seems the most promising short-term approach. From a long-term perspective, a formalisation of networks and stronger lobbying, especially on national level but also on EU level will be needed if framework conditions are to change in favour of a more diversified and flexible approach.
Tropical forests worldwide support high biodiversity and contribute to the sustenance of local people’s livelihoods. However, the conservation and sustainability of these forests are threatened by land-use changes and a rapidly increasing human population. This dissertation, therefore, aimed to characterize biodiversity patterns in the moist Afromontane forests of southwestern Ethiopia and to examine how biodiversity patterns are affected by land-use and land-use changes (mediated by coffee management intensity, landscape attributes and housing development) in a context of a rapidly growing rural population. To achieve this goal, the author takes an interdisciplinary approach where, first, she examined the effects of coffee management intensity on diversity patterns of woody plants and birds, spanning a gradient of site-level disturbance from nearly undisturbed forest interior to highly managed shade coffee forests. Results showed that specialized species of woody plants (forest specialists) and birds (forest specialists, insectivores and frugivores) were affected by coffee management intensity. The richness of forest specialist trees and the richness and/or abundance of insectivores, frugivores and forest specialist birds decrease with increasing levels of disturbance. Second, the author investigated the effects of landscape context on woody plants, birds and mammals. Community composition and specialist species of woody plants and birds were sensitive to landscape context, where woody plants responded positively to gradients of edge-interior and birds to gradients of edge-interior and forest cover. Further results showed that a diverse mammal community, with 26 species, occurs at the forest edge of shade coffee forests and that the leopard, an apex predator in the region depended on large areas of natural forest. A closer examination of leopard activity patterns revealed a shift in the diel activity as a response to human disturbance inside the forest, further highlighting the importance of natural undisturbed forests for leopards in the region. Together, these findings demonstrate the value of low managed shade coffee forests for biodiversity, and importantly, emphasize the irreplaceable value of undisturbed natural forests for biodiversity. Third, the researcher investigated the effects of prospective rural population growth (mediated by housing development) on the forest mammal community. Here, population growth was projected to negatively influence several mammal species, including the leopard. Housing development that encroached the forest entailed worse outcomes for biodiversity than a combination of prioritized development in already developed areas and coffee forest protection. Fourth, to understand the motivations behind high human fertility rates in the region, she examined the determinants of women fertility preferences, including their perceptions on social and biophysical stressors affecting local livelihoods such as food insecurity and environmental degradation. Fertility preferences were influenced by underlying social norms and mindsets, a perceived utilitarian value of children and male dominance within the household, and were only marginally affected by perceptions of social and biophysical stressors. The findings suggest the need for new deliberative and culturally sensitive approaches that engage with pervasive social norms to slow down population growth. Overall, this dissertation demonstrates the key value of moist Afromontane forests in southwestern Ethiopia for biodiversity conservation. It indicates the need to promote coffee management practices that reduce forest degradation and highlights that high priority should be given to the conservation of undisturbed natural forests. It also suggests the need to integrate conservation goals with housing development in landscape planning. A promising approach to achieve the above conservation priorities would be the creation of a Biosphere Reserve and to promote the ecological connectivity between the larger forest remnants in the region. Finally, this dissertation demonstrates the importance of placed-based holistic approaches in conservation that consider both proximate and distal drivers of forest biodiversity decline.
Transformative learning is increasingly set to become an essential component in sustainability transformation. Despite, little has been done to systematically explore the contribution to sustainability transformation. This learning theory developed decades ago independently of sustainability discourses; however, it provides an analytical framework for understanding the learning processes, outcomes and conditions in individual and social learning towards sustainability transformation. Against this background, the following research question arises: To which extent can transformative learning lead to sustainability transformation? This doctoral work aims to explore transformative learning processes, outcomes, and conditions occurring and advancing towards sustainability transformation of the textile-fashion industry in Mexico. Taking an exploratory approach, the methods employed were literature reviews to untangle concepts and to construct theoretical pillars to support the empirical research design and data analysis. For data collection, snowball-sampling techniques were used to explore the practice field of the textile-fashion industry in Mexico. Qualitative interviews were employed to gather data about the learning experiences of actors. Qualitative and quantitative methods were required to perform the respective data analysis, the qualitative codification of interviewees' responses. Analysis of social media content was also utilised to understand the communication and business practices of projects involved in the transformation of the textile-fashion sector. As a result, this work comprises three articles, one a systematic literature review and two empirical research articles, investigating the transformative learning processes of entrepreneurs in the development of sustainability niches. As for the findings of this doctoral work, the use of transformative learning in sustainability transformation requires a careful study of the theory and its conceptual elements. Regarding the case study, transformative learning is inherent in forming and developing sustainability niches as entrepreneurs venture into them: It is individual prior learning, expectations and actions that initiate the path of sustainability transformation while disorienting dilemmas, critical reflection, and discourse accelerate them. Through these stages, it is when individual learning turns into social learning. On the other hand, based on the multi-level perspective, the interplay between the niche, regime and landscape levels generates a space for sustainability transformation and transformative learning.
Wood-pastures have been present in Europe for thousands of years. This form of grazed landscape, combining herbaceous vegetation with trees and shrubs, has often co-evolved with its human users into complex social-ecological systems (SES). Wood-pastures are associated with high cultural and biodiversity values and are an example of the sustainable use of resources. However, due to their often relatively labour-intensive management and low productivity, large areas of wood-pastures have been lost over the last century. The loss of these areas means not only the loss of biodiversity on both local and landscape scales, but also the loss of traditional farming and cultural heritage in some regions. Across the European Union, wood-pastures are facing different problems and are embedded in different social systems and ecological environments. Yet they are all affected by global change and common European policies. To understand the challenges for wood-pastures in a changing world, a holistic approach combining different disciplines is needed. This dissertation therefore is analyzing wood-pastures across Europe as a Social-ecological System, combining ecology and social science with the aim to identify the barriers and drivers for wood-pastures persistence into the future.
Human activities have become a major driver of global change, so that global society and economy are facing consequences such as climate change, increasing scarcity of resources, environmental pollution and degradation as well as disturbances of ecosystem functioning and services.In order to meet these main challenges in an appropriate way, adequate starting points and solutions must be pursued at all levels to shift the current socio-economic pathway from an unsustainable to a safe operating and thus sustainable development within the planetary boundaries. One of the application concepts in industrial contexts is Industrial Symbiosis (IS), which deals with the set-up of advanced circular/cascading systems, in which the energy and material flows are prolonged for multiple material and energetic (re-)utilization within industrial systems in order to increase resource productivity and efficiency, while reducing environmental impacts. The overarching goal of the research project was to identify and develop approaches to enable the evolution of Industrial Symbiosis (IS) in Industrial Parks (IPs). IS is a collaborative cross-sectoral approach to connect the resource supply and demand of various industries in order to optimize the resource use through exchange of materials, energy, water and human resources across different companies, while generating ecological, technical, social and economic benefits. Many Information Communication Technology (ICT) tools have been developed to facilitate IS, but they predominantly focus on the as-is analysis of the IS system, and do not consider the development of a common desired target vision or corresponding possible future scenarios as well as conceivable transformation paths from the actual to the defined (sustainability) target state. This gap shall be addressed in this work, presenting the software requirements engineering results for a holistic IT-supported IS tool covering system analysis, transformation simulation and goal-setting. This study also aims to present the conceptual IT-supported IS tool and its corresponding prototype, developed for the identification of IS opportunities in IPs. This IS tool serves as an IS facilitating platform, providing transparency among market players and proposing potential cooperation partners according to selectable criteria (e.g. geographical radius, material properties, material quality, purchase quantity, delivery period). Therefore a quantitative indicator system was compiled and recurring patterns were identified to utilize this knowledge in the comprehensive IT-supported IS tool. So this IS tool builds the technology-enabled environment for the processes of first screening of IS possibilities and initiation for further complex business-driven negotiations and agreements for long-term IS business relationships.
Determinants of Emotional Experiences in Traffic Situations and Their Impact on Driving Behaviour
(2013)
Emotions play a prominent role in explaining maladaptive driving and resulting motor vehicle accidents (MVAs). Above all, traffic psychologists have focussed their attention on anger and anxiety, including the origins and influence of these emotions on driving behaviours. This dissertation contributes to the field with three manuscripts that build upon each other. Those manuscripts have three separate objectives. The first identifies the broad range of emotions in traffic that should be analysed. Second, the impact of specific emotions on driving behaviour is focussed. Finally, the research investigates how situational and personal factors can influence emotional experiences and influence driving behaviour. The first article tackles the bandwidth of emotions in traffic. In two consecutive online studies (study one: = 100; study two: n = 187), different emotional experiences were assessed using the Geneva Emotion Wheel (and an advanced version). The stimulus material consisted of written traffic situations structured around specific factors (in these studies, predominantly goal congruence, goal relevance and blame). It could be shown that the properties of the situation can elicit emotions such as anger, anxiety and happiness, but also pride, guilt and shame. The second article saw a transfer of those situational factor structures from online-presented text to simulated driving. At this time, the focus of interest was the driving behaviour influenced by the elicited emotions. The simulator study (n = 79) revealed that anger, contempt and anxiety led to similar declines in driving performance profiles. Performance declines included driving at higher speeds, more frequent speeding and worse lateral control. The third article examined to what extent anger and personal characteristics could negatively influence driving behaviour. Two studies were conducted (study one: n = 74; study two; n = 80). The results indicated that specific characteristics of the person (male, little driving experience, high driving motivation, high trait-driving anger) could influence driving behaviour in negative ways, both directly and indirectly, via triggered anger emotions. It can be concluded from these results that the range of emotions in traffic encompasses much more than just anger and anxiety. Furthermore, the second and third articles show that within simulated environments, minimal but effective emotional intensities can be triggered, and those emotions (especially anger and anxiety) create similar performance patterns. Personal characteristics should be considered when explaining the elicitations of emotion and subsequent driving behaviour. The papers of this dissertation echo the call for new comprehensive models to explain the relationships among emotions and traffic behaviours.
The dissertation consists of three scientific papers and a synopsis. The synopsis addresses the relevance of the dissertation and lists the key factors for the sustainability transition in the electricity system as a common denominator of the three papers. The relevance of the dissertation results, on the one hand, from the urgency of the sustainability transition in the electricity system and an insufficient transition willingness of the eastern European Member States. On the other hand, the Multi-Level-Perspective as one of the most important scientific frameworks to grasp transitions does not provide a sufficient explanation of its mechanisms. Moreover, Demand Response aggregators as new enterprises on the European electricity market and potential reform initiators are still under researched. The following key factors for the sustainability transition of the electricity system have been identified: supply security concerns, Europeanisation, policy making and the dominance of short-term oriented economic evaluation. Paper#1 sheds light on the roots of this problem in the context of Poland. It suggests that unfavorable regulation is symptomatic of the real, underlying barriers. In Poland, these barriers are coal dependence and political influence on energy enterprises. As main drivers, supply security concerns, EU regulatory pressure, and a positive cost-benefit profile of DR in comparison to alternatives, are revealed. A conceptual model of DR uptake in electricity systems is proposed. Applying a social mechanisms approach to the Multi-Level Perspective, paper#2 conceptualizes mechanisms of socio-technical transitions and of gaining legitimacy for transitions as co-evolutionary drivers and outcomes. Situational, action-formational, and transformational mechanisms that operate as drivers of change in a socio-technical transition require corresponding framing and framing contests to achieve legitimacy for that transition. The study illustrates the conceptual insight with the case of the coal dependent Polish electricity system. Paper #3, a qualitative study reveals Demand Response (DR) aggregators as institutional entrepreneurs that struggle to reform the still largely supply-oriented European electricity market. Unfavourable regulation, low value of flexibility, resource constraints, complexity, and customer acquisition are the key challenges DR aggregators face. To overcome them they apply a combination of strategies: lobbying, market education, technological proficiency, and upscaling the business. The study highlights DR aggregation as an architectural innovation that alters the interplay between key actors of the electricity system and provides policy recommendations including the necessity to assess the real value of DR in comparison to other flexibility sources by taking all externalities into account, a technology-neutral approach to market design and the need for simplification of DR programmes, and common standards to reduce complexity and uncertainty for DR providers.
The Macro Polity Revisited
(2021)
This dissertation includes six articles tied together by the overarching question of how changes in public opinion, economics and public policy co-evolve in mature democracies, with a focus on redistributive (in seven European democracies) and secessionist preferences (in Catalonia and Scotland). The theoretical inspiration derives from three sources: 1. the Macro Polity model by Erikson, MacKuen/Stimson, 2. the Thermostatic Responsiveness model by Soroka and Wlezien, and 3. the literature on representation gap models by Gilens, Elsaesser and others. The Macro Polity and Thermostatic Responsiveness models come with an optimistic undertone, emphasizing that public policies adapt to public opinion, producing the policy-opinion congruence that defines responsive government. The Representation Gap model, by contrast, is more pessimistic in highlighting that the preferences of low-income groups are generally worse represented in public policies than the preferences of middle-income and especially high-income groups. While there is evidence in favor of these models for the majoritarian political systems in the US, Canada and the UK, less is known about the validity of these models in proportional democracies of continental Europe. The contributions in this dissertation address this research gap by integrating the three models and combining nearly 500 surveys to study the evolution of European public opinion at the national and subnational level.
Both practitioners and researchers alike assign considerable importance to innovation. However, the process of how innovation unfolds over time is still not well understood. It is the aim of this dissertation to introduce an elaborated picture of innovation processes over time and to discuss the implications of the dynamics of the innovation process for individuals working in innovative contexts, that is, leaders and team members of innovative teams. The first paper of lays the theoretical and empirical groundwork of my dissertation in demonstrating that within the boundaries of the gradual development of innovation activities over time innovation processes are recursive and highly dynamic. These dynamics make the innovation process a challenge for everyone involved in it. In the second and third paper of my dissertation, I discuss this challenge in greater detail for leaders and team members of innovative work teams. Thus, with this dissertation I do not only to give a more elaborate picture of how innovation projects unfold over time, but also describe the challenges attached to the innovation process and give first answers to the question of how individuals involved in this process may be able to master these challenges.
Ziel dieser Arbeit ist es, empirisch gesicherte Aussagen über die schriftliche Textplanung von Mittelstufenschülern beim schriftlichen Argumentieren treffen zu können. Somit wird hier das argumentative Schreiben und Planen von schriftlichen Texten von Siebtklässlern betrachtet und untersucht. Die Daten resultieren aus dem Forschungsprojekt "!!Fach-an-Sprache-an-Fach!!". Im Rahmen dieses Projektes nahmen Schüler der 7. Klassen von insgesamt sieben Schulen in Niedersachsen und Hamburg an einer 15-wöchigen Intervention teil, um u.a. ihre schriftlichen persuasiven Argumentationsfähigkeiten zu verbessern. In diesem Zusammenhang arbeiteten die Schüler mit einem selbst entwickelten Planungstool, um argumentative Texte zu verschiedenen Aufgabenstellungen zu verfassen. In der Arbeit werden von 33 Fokusfällen die bearbeiteten Planungstools sowie die dazugehörigen argumentativen Texte in einem mehrstufigen qualitativen und quantitativen Analyseverfahren betrachtet. In dem Analyseverfahren wird u.a. mit der formal, strukturierenden qualitativen Inhaltsanalyse und mit einem gattungsspezifischen Textanalyseverfahren gearbeitet.
Vor dem Hintergrund der 2004 durchgeführten Reform auf dem Handwerksmarkt sollte anhand einer theoretisch-empirischen Analyse überprüft werden, ob Informationsasymmetrien bezüglich der Qualität auf dem Handwerksmarkt in unterschiedlicher Stärke auftreten und dementsprechend auch eine differenzierte Regulierung erfordern sowie inwieweit marktendogene und wirtschaftspolitische Lösungsmöglichkeiten zum Abbau von Informationsasymmetrien auf dem deutschen Handwerksmarkt wirken. Als empirische Datengrundlage wurde dazu eine Haushaltsumfrage durchgeführt, die neben der Ermittlung des Informationsnachfrageverhaltens auch die Beurteilung handwerklicher Qualität durch private Bauherren zum Ziel hatte. Die Befragung zeigt, dass trotz des Meisterbriefes Informationsasymmetrien auf den einzelnen Märkten bestehen, so dass eine über alle Gewerke geltende und den Wettbewerb stark einschränkende Regulierung in Frage gestellt werden muss. Die aus den Ergebnissen der Befragung deutlich gewordene Anwendung marktendogener Reputationsmechanismen zur Lösung von Informationsasymmetrien macht gleichzeitig den Schutz der Konsumenten als Regulierungsbegründung fraglich. Dies wird verstärkt durch die in der Befragung deutlich gewordene hohe Nutzung spezialisierter Dritter, die aufgrund ihrer Fachkenntnis keinen expliziten Verbraucherschutz benötigen sollten. Die Handwerksnovelle 2004 stellt somit insbesondere durch die Auflockerung der Marktzutrittsbeschränkungen aus informationsökonomischer Sicht einen Schritt in die richtige Richtung dar.
This dissertation contributes to research on generating actionable knowledge for coastal governance to enhance the resilience of coastal social-ecological systems (SES) to climate change. It does this by providing theoretical, methodological and empirical insights on three research questions (RQs). These are: (1) what is a more actionable concept for applying the concept of resilience in coastal governance?; (2) what methods and approaches are suitable to generate actionable knowledge for coastal governance?; (3) what obstacles to knowledge co-production exist for early-career researchers (ECRs) and how can they be overcome? The RQs are addressed in five publications. For answering RQ1, the dissertation applies a research synthesis to bring together common themes and challenges documented in resilience, climate change and environmental governance literature. For answering RQ2, different methods and approaches for generating actionable knowledge are proposed and tested using a case-study in the SES of Algoa Bay, South Africa. These include (i) the analysis of stakeholder agency; (ii) the application of a stakeholder analysis; and (iii) the combination of a capital approach framework, and fuzzy cognitive mapping. Finally, for answering RQ3, the thesis provides a perspective on the obstacles that especially ECRs face, and actions that are needed to create the conditions under which knowledge co-production processes can be successful. This is done by applying a multi-method approach combining an online survey and workshop targeted at ECRs in the marine sciences. Key findings suggest that system and transformative knowledge are particularly important when applying the concept of resilience in coastal governance to generate actionable knowledge. The different methods and approaches that are proposed and tested contribute to generating both system and transformative knowledge. Firstly, they provide an overview of the capacities of different stakeholders to act, shed light on current collaboration and knowledge exchange, and enable the identification of different governance processes for coastal governance and climate change adaptation (system knowledge). Secondly, results have implications for how to improve knowledge exchange and identify leverage points that can enhance overall governance performance, thus providing recommendations on actions and processes that can enhance climate resilience in the case-study area (transformative knowledge). It is also highlighted how knowledge co-production can contribute to generating system and transformative knowledge together with stakeholders, and what actions are needed to build the capacities to translate knowledge into action. Additionally, the findings of this dissertation put forward actions that are needed at different organisational levels of the academic system to facilitate knowledge co-production processes with stakeholders involved in coastal governance. The results of this dissertation have implications for stakeholders and decision-making in the case-study area, as well as for environmental governance, climate change adaptation and broader sustainability research. Implications for stakeholders include recommendations for implementing formal commitments to share climate information across levels and sectors, establishing the role of information providers in the municipality, and reinforcing human capital within the local municipality in Algoa Bay. Findings also suggest the need for a more integrated approach to climate change adaptation in coastal planning and management frameworks. It also suggests that the conservation of environmental assets presents an important bottleneck for resilience management and needs to be further prioritised within decision-making. Implications for research include the applicability of methods beyond the context of this dissertation; a more actionable concept for approaching resilience in (coastal) governance systems; and a more critical reflection on how transformative research is conducted, and what academic foundation is needed so that it can fulfil its societal goal.
'Bildung für das Leben in der Weltgesellschaft' – eine dokumenten- und fallanalytisch gestützte Untersuchung des Bildungskonzepts der UNESCO-Projektschulen Deutschlands. Die vorliegende Studie begibt sich auf die Suche, eine bildungstheoretische Antwort auf die Herausforderungen unserer Zeit zu finden. Schon 1953 hat die UNESCO vor diesem Hintergrund mit dem ASP-net ein Modellprojekt initiiert, das in dieser Dissertation nachgezeichnet und auf deutscher Ebene eruiert werden soll. Im Titel der Dissertation wird bewusst das Bildungsziel der UNESCO-Projektschulen aufgenommen, da die Untersuchung eine Generierung von Leitbildern gelungenen Lernens und Lebens in Schulen einer globalisierten Gesellschaft verfolgt. Es gilt zu untersuchen, inwiefern der anfängliche Auftrag, neue Methoden und Inhalte einer „Erziehung zu internationaler Verständigung“ zu entwickeln, realisiert wird. Hierfür werden die wichtigsten Referenzdokumente der UN und der UNESCO analysiert. Ihre Umsetzung wird anhand von vier Einzelfallstudien und der Auswertung der Jahresberichte von 177 Schulen des deutschen Netzwerks überprüft.
The Sustainable Development Goals (SDGs) recognize the importance of the inextricable link between social and ecological systems and human quality of life (QoL) and biodiversity. Therefore, understanding the feedback and interactions between biodiversity, nature’s contributions to people (NCP), and QoL plays a central role in advancing toward sustainability. In this context, the social-ecological systems (SES) approach has advanced on the subject, particularly in recent decades; however, much remains to be done to comprehensively understand these relationships and interactions, especially at local decision-making scales. In this thesis, through the lenses of the SES approach, the researcher investigates connections between biodiversity, NCP, and QoL in a tropical dry forest (TDF) on the Western coast of Mexico. This place is one of the best-known Neotropical TDF and has been the focus of SES research in the past 20 years, making it an excellent case study for exploring these connections. First, to approach the need for dialogue among different global and local scales and between global and local frameworks, the thesis identifies five key components of the SES dynamics-(1) ecological supply, (2) co-production of NCP, (3) management, (4) demand, and (5) benefits - and three local decision-making scales of analysis: individual plot, smallholder, and land tenure or governance units. A literature review was performed on the social-ecological indicators for the last 11 years in the Chamela-Cuixmala region to operationalize this framework. Second, this thesis uses social-ecological information to identify social-ecological systems units (SESU) spatially explicitly. A methodology was provided to spatially identify the components of social-ecological systems that environmental conditions and management practices have shaped at three previously stated relevant decision-making scales: plots owned by individuals, plot owners, and governance units. To do so, the research group identified and characterized: (1) ecological clusters (EC), (2) social-management clusters (SC), and (3) SESU in a TDF in western Mexico. The findings suggested that decision-makers (ejidatarios, i.e., type of ownership (related to agrarian reform), that in most cases the land allocated is small-smallholders) are bounded by the topographical characteristics and the public policies that determine communal (or private) governance and the number of resources available to them. Finally, the thesis examines the self-perceived QoL across the different SESU, finding 48 QoL items, which were grouped into six categories: 1) social capital, 2) economic capital, 3) agency, 4) nature, 5) peasant non-work activities, and 6) government and services; and two additional dimensions referred to obstacles and enablers of QoL. The researchers found that the more land cover transformation, the more enablers, and obstacles of QoL are identified; emphasis was put on economic capital to achieve QoL. As management is intensified and governance fosters individualism across SES, the higher the Current Welfare Index, and the lower the self-perceived material and non-material satisfaction.
Though the loss of biological diversity is an ecological phenomenon, it also has a social dimension. This makes the study of the social landscape, encompassing the multitude of perspectives and aspirations by different stakeholders, highly relevant for better navigating trade-offs between biodiversity conservation and other land use objectives. Engaging with and addressing contextual understandings of biodiversity is vital to develop socially palatable solutions for biodiversity loss. This dissertation, therefore, takes a place-based approach to studying biodiversity conservation trade-offs and seeks to understand how the perspectives and aspirations of different stakeholders shape them. First, it aims to identify shared viewpoints as ensembles of perceptions and meanings about human-nature relations and biodiversity. Second, it aims to understand how biodiversity is valued and constructed in stakeholders’ aspirations towards their landscape. To this end, a convergent mixed methods approach and case study design are used. Two cases were selected that face different underlying drivers of land-use change, resulting in loss of biodiversity. The Muttama Creek Catchment area is a farming landscape in south-eastern Australia where the ongoing intensification of agricultural production threatens native biodiversity. In the Spreewald Biosphere Reserve in north-eastern Germany, land abandonment and the resulting loss of the biodiversity-rich wet meadows presents a key challenge for biodiversity conservation. Narratives and discourses provide conceptual lenses through which the author studies biodiversity conservation trade-offs. Drawing on Q-methodology, this dissertation identifies biodiversity-production discourses for the first case study and cultural landscape narratives for the second case study. Moreover, based on a participatory futures approach, the Three Horizons Framework, it elicits narratives of change that highlight opportunities for biodiversity conservation in farming landscapes. The findings highlight that despite some overlap in how stakeholders perceive biodiversity, contrasting problem framings and different biodiversity priorities present hindrances to concerted action to protect biodiversity and for collaboration. The findings also identify shared values among stakeholders. However, there is polarity and contestation around the role and importance of biodiversity in rural development.
The world wide population growth and the increasing water scarcity endanger more and more the human society. Water saving measures alone will not be sufficient to solve all associated problems. Therefore, people in arid countries might come back to any kind of water available. In this context the way people regard wastewater must change in terms that it has to be recognized as a water resource. The reuse of wastewater, treated and untreated, for irrigation purposes in agriculture is already established in some semi-arid and arid countries. Countries with absolute water scarcity like Israel might not only be forced to reduce their water consumption, but even to transfer reused water to other sectors. Concerns of authorities and the general public about potential health risks are completely understandable. The health risks of wastewater are mainly originating from pathogens which are negatively correlated with its treatment. Therefore, the quality of a wastewater effluent derived from mechanical-biological treatment can be further improved by additional treatment steps like soil aquifer treatment (SAT). This process is adopted at the Israeli Shafdan facility in the south of Tel Aviv. Conventionally treated wastewater is applied on surface basins from where it percolates into the coastal plain aquifer which supplies approximately one quarter of Israel ́s drinking water. After a certain residence time in the subsurface the water is recovered by wells surrounding the recharge area. Although the pumping regime creates a hydraulic barrier to the pristine groundwater, concerns exist that a contamination of the surrounding drinking water wells could occur. So far, little is known about the removal of organic trace pollutants during the SAT process in general and for the Shafdan site in particular. Consequently, the need arose to study the purification power of the SAT process in terms of the removal of organic trace pollutants. For this purpose reliable wastewater tracers are essential to be able to differentiate between degradation and sorption processes on the one hand and dilution with pristine groundwater on the other hand. Based on their chemical properties, their worldwide usage in a variety of foodstuffs and beverages, and first data about the fate and occurrence of sucralose, artificial sweeteners came into the focus as promising tracer candidates.
Thus, in the present work an analytical method for the simultaneous determination of seven commonly used artificial sweeteners in different water matrices, like surface water and wastewater, was developed (see chapter 2). The method is based on the solid phase extraction (SPE) of the analytes by a styrene-divinylbenzene (SDB) copolymer material, and the analysis by liquid chromatography-electrospray ionization tandem mass-spectrometry (LC-ESI- MS/MS). The sensitivity in negative ionization mode was considerably enhanced by postcolumn addition of the alkaline modifier tris(hydroxymethyl) aminomethane. In potable water, except for aspartame and neohesperidine dihydrochalchone, absolute recoveries >75 % were obtained for all analytes under investigation, but were considerably reduced due to matrix effects in treated wastewater. The widespread distribution of the artificial sweeteners acesulfame, saccharin, cyclamate, and sucralose in the aquatic environment was proven. Concentrations in two German wastewater treatment plant (WWTP) influents ranged up to 190 μg/L for cyclamate, several tens of μg/L for acesulfame and saccharin, and about 1 μg/L for sucralose. For saccharin and cyclamate removal rates >90 % during wastewater treatment were observed, whereas acesulfame and sucralose turned out to be very persistent. As a result of high influent concentrations and low removal rates in WWTPs, acesulfame was the dominant sweetener in German surface waters with concentrations up to 2.7 μg/L. The detection of acesulfame and sucralose in recovery wells in the Shafdan SAT site in Israel in the μg/L range was a promising sign for their possible use as anthropogenic markers. As acesulfame and sucralose showed a pronounced stability in WWTPs and were detected in recovery wells of the SAT site in Israel it became worthwhile to assess their tracer suitability compared to other organic trace pollutants suggested as anthropogenic markers in the past (see chapter 3). Therefore, the prediction power of the two sweeteners was evaluated in comparison with the antiepileptic drug carbamazepine (CBZ), the X-ray contrast medium diatrizoic acid (DTA) and two benzotriazoles (1H-benzotriazole (BTZ) and its 4-methyl analogue (4TTri)). The concentrations of these compounds and their ratios were tracked from WWTPs with different treatment technologies, to recipient waters and further to river bank filtration (RBF) wells. Additionally, acesulfame and sucralose were compared with CBZ during advanced wastewater treatment by SAT in Israel. Only the persistent compounds acesulfame, sucralose, and CBZ showed stable ratios when comparing influent and effluent
concentrations of four German WWTPs with conventional wastewater treatment. However, by the additional application of powdered activated carbon in a fifth WWTP CBZ, BTZ, and 4-TTri were selectively removed resulting in a pronounced shift of the concentration ratios towards the nearly unaffected sweeteners. Results of a seven months monitoring program along the rivers Rhine and Main showed an excellent correlation between CBZ and acesulfame concentrations (r2 = 0.94), and still good values when correlating the concentrations with both benzotriazoles (r2 = 0.66 - 0.82). In RBF wells acesulfame and CBZ were again the compounds with the best concentration correlation (r2 = 0.85).
As human rights evolved to become part of a dominant moral discourse in world politics, regional organisations (ROs) often portray themselves in the language of human rights. Facing growing contestation and politicisation, they have also gradually begun to legitimate their authority drawing on human rights. Yet not all ROs do so to the same extent, in the same manner, or consistently over time. This begs the question: why and how do ROs use human rights for self-legitimation? To answers this research question, I combine a macro analysis using qualitative comparative analysis (QCA) on 23 ROs from 1980 to 2019 with a micro analysis via process-tracing in two cases - Arab League (LoAS) and the Caribbean Community (CARICOM). Ultimately, ROs use human rights in their legitimation because they strive for congruence. When norms, values, and moral principles purported and embodied by the RO are congruent with those of its core constituency and all relevant audiences, The researcher observes human rights legitimation. She argues that the degree of congruence combines with different degrees of delegitimation stemming from the distinct constellation of agents and audiences of legitimation. Shee circumscribes this via four types of human rights legitimisers. Testing existing theories on legitimacy, legitimation, and human rights, the QCA suggests that "Self-containing Legitimisers" are ROs with a status quo of congruence between the RO and its core constituency. "Signalling Legitimisers" irregularly use human rights legitimation as a signal to respond to additional audiences. Thanks to the case studies, the author further refines existing theory. CARICOM constitutes a case of a "Reviving Legitimisers" where delegitimation towards their core constituency occurs to which it reacts by reviving what it embodies which entails including human rights in its legitimation. With LoAS, the author observes a "Brokering Legitimisers" in which case delegitimation is on the verge of a legitimacy crisis, but its Secretary General manages to broker human rights to two diverging audiences thanks to localisation. Thus, this book provides an explanation of how a distinct norm is used in self-legitimation, nuances our understanding of agents and audiences of legitimation, and introduces the concept of localisation to the study of legitimation.
Polyzyklische Aromatische Verbindungen (PAV) im Grundwasser teerölkontaminierter Altlastenstandorte
(2010)
Es wurde das Grundwasser von sieben verschiedenen mit teerölkontaminierten Altlastenstandorten in Deutschland (Stuttgart, Düsseldorf, Wülknitz, Lünen, Offenbach, Karlsruhe) und Österreich (Brunn am Gebirge) untersucht. 45 Einzelverbindungen, darunter PAK, NSO(hetero)-PAV sowie Derivate und Metabolite der PAK und PAV, konnten dabei in signifikanten Konzentrationen nachgewiesen werden. Für alle betrachteten Standorte ergab sich ein vergleichbares Schadstoffmuster. Allein 22 Verbindungen konnten für alle Standorte nachgewiesen werden. Die Identifizierung und Quantifizierung der PAK und PAV erfolgte mittels flüssig-flüssig-Extraktion und an-schließender GC-(EI)-MS Messung der Proben. Besonders zwei Standorte (Karlsruhe, Brunn a.G.) mit einer reaktiven Wand als Sanierungsverfahren wurden genauer betrachtet. Die Untersuchungen ergaben, dass es ab Inbetriebnahme der Anlagen mit Hilfe des reaktiven Reaktormaterials Aktivkohle über 10 Jahre möglich war, neben den hinlänglich bekannten EPA-PAK, auch die polareren, gut wasserlöslichen und in erhöhten Konzentrationen auftretenden NSO(hetero)-PAV sowie deren Derivate und Metabolite erfolgreich aus dem kontaminierten Grundwasserstrom zu entfernen.
This work investigates how managers/consultants (practitioners) of different ranks are engaged in patterns of behavior (practices) in socially situated contexts (practice) attempting to shape preferred shared interpretations of reality to achieve their goals. Following this line of inquiry, the work aims at (1) advancing our understanding of the role of practitioners in shaping managerial realities and (2) investigating how practitioners actually shape managerial realities, particularly focusing on "reality-shaping" practices and their content. The dissertation comprises a set of four complementary articles investigating these research questions empirically based on in-depth, empirical case studies and theoretically within various managerial contexts (client-consultant relationship, CEO post-succession strategic change process, evolutionary initiative development) and considering different actor perspectives (top managers, middle managers, consultants and clients). Resulting from this variety, the articles rely on and contribute to different, at times distant, research fields and therewith scholarly discussions. However, the literature on sensemaking and sensegiving offers a suitable overarching theoretical frame which is used in this work to synthesize the key contributions of the four articles.
In Deutschland weitet sich die ganztägige Beschulung aus. Damit geht für Kinder und Jugendliche ein Rückgang der freien Zeit einer. Diese ist für die Ausbildung und Intensivierung von Freundschaften und Peerbeziehungen gerade in der Adoleszenz bedeutend. Im Fokus dieser Dissertation steht die Frage nach der Gestaltung einer peer-gerechten Schule, in der die Entwicklungsbedürfnisse Jugendlicher berücksichtigt werden. Anhand der Triangulation von Ergebnissen aus Befragungen von ca. 400 Jugendlichen aus Halbtags- und Ganztagsschulen zu Beginn und zum Ende der siebten Klasse mittels einer offenen Frage im Fragebogen zu Aspekten einer peer-gerechten Schule und der mit einem teilstrukturierten Interview zur Qualität ihrer Freundschaften erhobenen Antworten von 14 Jugendlichen aus einer Ganztagsschule aus der siebten Jahrgangsstufe wird in dieser qualitativ-empirischen, explorativen und deskriptiven Untersuchung dargestellt, wie in der Schule die Entstehung und Aufrechterhaltung von intimen, im psychologischen Sinne vertrauensvollen, Freundschaften unterstützt werden kann, welchen aus entwicklungspsychologischer Sicht eine besondere Bedeutung zugeschrieben wird.
Due to the financial markets disturbances of 2007/2008, a considerable number of financial intermediaries such as banks, credit institutions and asset management companies noticed substantial liquidity shortages, difficulties to refinance their operations as a result of a drying out of appropriate refinancing sources, and withdrawals of deposits by consumers. These turbulences in the financial markets forced governments and central banks to increase liquidity provisions to ensure a sufficient aggregate liquidity of the financial industry. Furthermore, policy-makers decided on bailouts of banks or on supporting financial intermediaries by governmental warranties or liquidity provisions to avoid a substantial number of insolvencies of banks and other financial institutions that may have rapidly deteriorated the global financial industry. In the aftermath of the crisis, politicians and economists discussed these decisions controversially because interventions by governments and central banks appear to have a deep impact on the global economy particularly in the financial industry. Moreover, legislative and regulatory authorities decided on increasing their vigilance, particularly with focus on principal-agent problems within certain sectors of the financial industry. A considerable amount of recent research papers has focused on the dynamics of liquidity shortages that suggest the recent crisis being related to both an increasing funding liquidity risk and an emerging market liquidity risk. Self-amplifying interdependencies appear to connect these two dimensions of liquidity risk that during the period 2007 to 2008 have led to the contagion effects in the global financial industry. Only little research work so far has provided evidence from the financial crisis in 2007/2008 while focusing on the German financial industry. Thus, my doctoral dissertation covers three research papers that address the occurrence of substantial liquidity risk and default probability within the German financial industry over the course of the financial crisis of 2007/2008. My first publication co-authored with Daniel Schmidt, Leuphana University of Lüneburg, entitled ‘Consumer reaction to tumbling funds - Evidence from retail fund outflows during the financial crisis 2007/2008’ focuses on funding liquidity risk of German retail funds. Contrary to the findings reported in some of the extant literature, our study indicates that over the past few years a change in investors’ behavior patterns means that investment decisions are made at short notice, and that shares are redeemed in a discriminatory manner when funds perform poorly. By using data assembled from 1672 retail funds in Germany over the period March 2008 to April 2010, we are able to show that in general, both the prior fund performance and prior net redemptions have a statistically significant influence on fund outflows. Moreover, there are indications that in recent crises situations that have resulted in the withdrawal of shares investors react fast to market signals. My second research paper entitled ‘Leveraging and risk-taking within the German banking system: Evidence from the financial crisis in 2007 and 2008’ examines the risk-taking attitudes of distinguishable German banking sectors. This study intends to examine whether the German banking system displays pro-cyclical behavior during 2000 to 2011, and to what extent specific sectors of the German banking system show significant balance sheet operations to increase their leverage during years of booming asset prices. The results of this study demonstrate that different sectors of the German banking system did operate their business more or less pro-cyclical. It also provides empirical evidence that certain banking sectors did favor refinancing their assets by short-term borrowing in the interbank market to increase their leverage during periods of extraordinary high returns in financial markets. Moreover, this study shows that banks, which operate above average leverages, tend to report a high volatility of return on assets and low distances-to-default. Finally, my third paper entitled ‘Are private banks the better banks? An insight into the ownership structure and risk-taking attitudes of German banks.’, and co-authored with Thomas Wein, Leuphana University of Lüneburg, tries to enlighten the influence of the different principal-agent relationships on the risk-taking attitudes of German banks. In this study, we propose our hypothesis that the distinguishable principal-agent relationships of German banks are significantly influencing the risk-taking attitudes of bank managers. Particularly, we intend to substantiate the theory that banks owned by dispersed shareholders or federal state authorities face a higher relevance of principal-agent problems than other banking sectors due to a missing ability to monitor bank managers. Our results underline that these problems appear to mislead bank managers showing an unreasonable risk-taking behavior. In a first stage, we rely on a theoretical model explaining that from the bank owners’ viewpoint three factors of the principal-agent relationships are determining the probability of choosing the optimal portfolio of risky assets. These factors cover the ability to control bank managers, the risk pooling capabilities of bank owners and bank managers, and the incentives of seeking high returns. To support our hypothesis we apply an empirical study to the distances-to-default of different German banking sectors. This demonstrates that risk-taking attitudes of banks are closely related to banks’ ownership. Consequently, our findings offer evidence, that legislative and regulatory authorities should increase their vigilance in terms of principal-agent problems within certain sectors of the banking industry.
In recent years, both scientists and practitioners have become interested in the affectivemotivational concept of work engagement and research on work engagement has strongly accumulated. Engaged people invest physical, affective, and cognitive resources in their work tasks and activities (Sonnentag, Dormann, & Demerouti, 2010) and high levels of work engagement involve positive consequences both for the individual and the organization (Rich, Lepine, & Crawford, 2010). The objective of this dissertation is twofold. The first and second empirical studies help to advance knowledge on antecedents of work engagement and to extend theoretical models in which work engagement is embedded. The third study aims at expanding present knowledge of the role of specific work events as proximal antecedents of distinct affective states and as distal antecedents of job attitudes and affective consequences such as work engagement by developing a taxonomy of work events. This dissertation suggests ideas for future research and provides practical implications regarding work design and human resource practices that are based on the empirical findings reported. Study 1 investigates the cognitive-motivational concept of focus on opportunities (i.e. the number of goals, plans, and possibilities employees believe themselves to have in their future) as a predictor of work engagement and a personal resource that buffers for low levels in employee’s job control. By using a cross-sectional survey study based on a sample of bluecollar workers (N = 174), and a daily diary study based on a sample of administrative employees (N = 64), this study revealed that job control was less strongly related to work engagement when people’s focus on opportunities was reported to be high. Employees with a high focus on opportunities compensated for low job control. This finding refines theoretical models of antecedents of work engagement by supporting the role of focus on opportunities as a motivational resource. The goal of Study 2 was to examine self-efficacy regarding a person‘s work role as a personal resource that helps employees to effectively regulate affective states in a way to show high levels of work engagement. The study was conducted based on a sample of 111 full-time employees who completed daily online questionnaires on affective experiences and work engagement twice a day over ten working days. Results of multilevel linear regression analysis showed that self-efficacy acted as a moderator on the relationship between daily negative affect and daily work engagement. Self-efficacy enabled people to show high levels of work engagement on days when they experience negative affective states. Moreover, the relationship between self-efficacy and work engagement was mediated by an increase of positive affect during the day. Through the mechanism of up-regulating positive affect, people high in self-efficacy succeed in maintaining daily work engagement. These results extend existing theoretical frameworks of work engagement by indicating that self-efficacy is an important personal resource that enables people to effectively regulate affective states and show high levels of work engagement. Study 3 addresses the development of a comprehensive taxonomy of daily work events that provides a frame of reference for future studies to more systematically test propositions of Affective events theory (AET) (Weiss & Cropanzano, 1996). AET provides a theoretical framework that emphasizes the role of work events as proximal antecedents of affect but does not formulate specific propositions about which kind of work events elicit distinct affective states. Based on 559 positive and 383 negative work events mentioned in three daily diary studies by an overall of 218 employees, the qualitative concept mapping methodology was used to establish the taxonomy on work events. Explorative statistical analyses resulted in four positive and seven negative work events clusters. The study provides evidence for the validity of the taxonomy by testing the relationships of the events clusters with distinct positive and negative activating and deactivating affective states.
Considering the recent success of right-wing populist candidates and parties in the United States and across Europe, there has for some years now been talk among scholars (and the wider public) about a worldwide democratic recession. The younger generations appear to be especially unsupportive of democracy’s liberal principles and more willing to express support for authoritarian alternatives. What these authors overlook, however, is that the publics of advanced industrial societies have experienced an intergenerational value shift. In fact, populations in industrial democracies have become more liberal overall, but not everyone’s mindset is changing at the same speed. It is mainly – but not exclusively – the members of the lower classes that do not keep up. While societies have generally become more liberal, there is increasing alienation between the social classes over these liberal values. Drawing on a more recent trend in social class research with a social cognitive approach, this dissertation contributes to the study of growing anti-democratic tendencies around the world by analyzing the interplay between inequality dynamics and value orientations. The focus lies on investigating the effect socio-cultural polarization (i.e., ideological polarization between social classes) has on civic culture in the mature democracies of the West. The findings suggest that it is not ideological polarization between the social classes that has the greatest negative effect on civic culture, or general civic attitudes and behavior, for that matter. It is the increasing dissent in society about whether the country’s elites are still to be trusted with making the right decisions to increase the average citizen’s quality of life. This difference in opinion manifests itself in a decline in some civic attitudes.
Im Rahmen der Arbeit wird ein neues Struktur-Prozess-Modell (OASIS-Modell) zur Abbildung von Informationsprozessen im Rahmen touristischer Entscheidungs-prozesse erarbeitet und begründet. Teilaspekte des Modells werden mit Hilfe eines Mehr-Methoden-Ansatzes empirisch überprüft. Ein wesentliches Ziel der Arbeit ist die Untersuchung der Methoden zur Erhebung der Informations-verarbeitung. Dazu liegen eigene Ergebnisse mit drei verschiedenen empirischen Methoden (Befragungen, IDM-Experimente, Eye-Tracking-Experimente) vor. Ein Schwerpunkt der Methodenentwicklung und des Methodeneinsatzes wurde auf die Information Display Matrix gelegt. Dazu wurde mit dem IDM Visual Processors ein komplett neues Experimentalsystem erarbeitet. Das Programm verknüpft flexible Experimentalsituationen mit einer integrierten Auswertungslogik, so dass die Datenanalyse erheblich vereinfacht oder überhaupt erst mit vertretbarem Aufwand ermöglicht wird. Vom System noch nicht geleistete Analyseaufgaben können aufgrund der verwendeten Standarddatenbank mit Hilfe einfacher Datenexports in anderen Systemen erledigt werden. Im Rahmen der Analyselogik werden erstmals auch dreischrittige Transitionen in Echtzeit berechnet. Damit ist es möglich, weitere abgeleitete Koeffizienten mit vertretbarem Analyseaufwand zu generieren.Zentrales inhaltliches Ergebnis der Arbeit ist die Erstellung eines Modells zur Strukturierung und empirischen Überprüfung des Informationsverhaltens von Urlaubsreisenden. Dieses nach seinen fünf zentralen Dimensionen benannte OASIS-Modell vereint 1. Ein fünfdimensionales Informationsfeld 2. Ein Strukturmodell der möglichen Einflussfaktoren nach vier Dimensionen 3. Die Integration der beiden Modellelemente in eine funktionale und zeitliche Dimension des Entscheidungs- und Informationsprozesses. Die Entwicklung des Modells beruhte auf der genauen Analyse von ca. 20 bereits bestehenden Prozess- und Strukturmodellen sowohl des allgemeinen als auch des touristischen Entscheidungs- und Informationsverhaltens. Im Vergleich zu bestehenden Modellansätzen sind damit vor allem die folgenden Fortschritte gelungen: 1. Das Informationsfeld wird durch die Teilung in fünf Dimensionen für die Analyse besser fassbar: Sowohl die Wirkung der persönlichen, situationalen, produktbezogenen und externen Einflussfaktoren auf jede der Dimensionen als auch die Wechselwirkungen zwischen den Dimensionen können empirisch überprüft werden. Zwar ergibt sich allein innerhalb der Dimensionen des Informationsfeldes eine Zahl von 10 bi-dimensionalen und 45 multidimensionalen Wirkungsfeldern, die durch entsprechende Analysen hinterlegt werden müssten. Damit wird aber lediglich die Komplexität des tatsächlichen Informations- und Entscheidungsverhaltens abgebildet. 2. Die vier Dimensionen der Einflussfaktoren erlauben wiederum die Analyse ihrer Wirkung auf das Informationsfeld, aber auch die Analyse ihrer Wechselbeziehungen. 3. Die Einbettung des Strukturmodells in einen längeren Prozess und die Definition einer vier-schrittigen Informationsepisode wird postuliert. Im Zuge der Untersuchung ist es gelungen, mit Hilfe verschiedener Erhebungs- und Analysemethoden Teilbereiche des Modells zu prüfen und zu erklären. Ein gesamtheitliche Überprüfung des Modells wird aber auch in Zukunft kaum gelingen. Insofern gibt es für die zukünftige Forschung nur zwei Wege: Entweder die Komplexität des Modells so weit zu reduzieren, dass es mit einem einheitlichen Analyseansatz greifbar wird (wogegen aber die große Zahl bereits vorhandener Teilmodelle spricht), oder das Modell als Arbeitsrahmen zu sehen, in dem Teilbereiche sukzessive untersucht und überprüft werden. Dieser Weg ist mit der vorliegenden Untersuchung begonnen worden.
Die Arbeit beschäftigt sich mit dem Thema der Erlebnisqualitätsmessung. Hierfür werden sowohl der Erlebnisbegriff als auch der Customer Experience Management Ansatz herangezogen als auch Modelle zur Qualitätsmessung analysiert. Das Customer Experience Management kann als Weiterentwicklung des klassischen Qualitätsmanagements verstanden werden und integriert insbesondere die Ansätze des Markenmanagements. Schließlich liefert der empirische Teil der Arbeit wesentliche Erkenntnisse darüber, wie Erlebnisqualität gemessen werden kann und wodurch sie beeinflusst wird. Dies erfolgt am Beispiel einer durch einen Reiseveranstalter organisierten Badepauschalreise, sodass die Ergebnisse unmittelbar in Implikationen für die künftige Gestaltung einer Urlaubsreise münden.
This cumulative dissertation presents how commercial banks in Germany communicate their ambitions and commitment regarding corporate responsibility - i.e., CSR. The results of the first article show that the quality of mandatory non-financial reporting needs to be improved and that certain characteristics (e.g., previous reporting experience, reporting format and standard) have a positive influence on reporting quality. The second article shows that the CSR reporting scope on bank websites also has room for improvement and that various banking characteristics such as size, capital market orientation, media visibility or public ownership have an influence on communication. The third article illustrates that credit institutions in Germany are increasingly using social media for CSR communication, but that CSR communication strategies differ (Facebook vs. Twitter). The fourth article discusses CSR communication using advertisements and shows that the conceptual design of advertisements should be in line with the credit institution's business model and is therefore beneficial.
Die Agenda 2030 der Vereinten Nationen und diverse daraus abgeleitete Nachhaltigkeitsstrategien setzen einen zeitlich fest definierten Rahmen bis in das Jahr 2030. Für die Umsetzung dieser Strategien sind zwei Aspekte entscheidend - ein fundiertes inhaltliches Verständnis von politischer Strategie und ein darauf aufbauendes praxistaugliches Instrument, das den politischen Strategen bei einer erfolgreichen Umsetzung und Implementierung einer Strategie unterstützt. Diese Arbeit möchte zu beiden Aspekten einen Beitrag leisten. Zum einen wird aus der Zusammenführung von Theorie und Praxis die Natur des inhaltlichen politischen Strategiebegriffs erforscht. Zum anderen wird darauf aufbauend ein praxis- und erfahrungsorientiertes Anwendungsmodell entwickelt, das typische potentielle Herausforderungen und entsprechende potentielle Handlungsoptionen je Strategieabschnitt benennt. Durch die Subsumierung von Erfahrungswissen unterstützt das Modell dabei vor allem das praktische Urteilsvermögen des politischen Strategen bei der Erreichung politikstrategischer Ziele. Um zu dem praxisrelevanten Anwendungsmodell zu gelangen ist es notwendig, sich zuvor Klarheit über die besonderen Anforderungen und Herausforderungen des speziellen politischen Strategiebegriffs zu verschaffen. Die politische Umwelt mit ihren spezifischen Mechanismen unterscheidet sich fundamental von den bisher bekannten Strategiefeldern Militär und Betriebswirtschaft. Da eine Strategie immer die konkrete Umweltsituation und die individuellen Situationsmerkmale berücksichtigen muss, ist - wie diese Arbeit zeigt - eine simple Übertragung strategischer Allgemeinplätze aus Militär und Ökonomie von vornherein zum Scheitern verurteilt.
This study examines the perspective of German venture capitalists on the success factors of digital startups and follows an explorative three-dimensional research approach that integrates the micro perspective on the entrepreneurial personality, the macro perspective on the entrepreneurial context, and the meso perspective on the business model. Thus, the study operates in a very young field of entrepreneurship research. One of the purposes of this research project is to work out the significance of particular characteristics at each research level for the economic success of a digital start-up from the perspective of German venture capitalists. Furthermore, the study sheds light on the view of this group of experts on the relevance of an entire group of characteristics. To answer the central research questions, qualitative research methods and a mixed-methods approach are pursued, with quantitative and qualitative primary data being collected by means of theory-driven semi-structured expert interviews. As a result, a total of four articles have been produced: three articles that focus on presenting the results of qualitative research from only one of the three aforementioned research perspectives each, and a fourth article that combines methods from qualitative and quantitative research and derives an integrated, evidence-based working model of the economic success of digital startups from the perspective of German venture capital (VC) investors.
Diese Dissertation verfolgt einerseits das Ziel der umfassenden Sichtung der technischen, psychologischen, philosophischen und neurobiologischen Grundlagen der Künstlichen Intelligenz und damit die Etablierung einer epistemischen und ontologischen Eingrenzung der Technologie und andererseits das Ziel der moralphilosophischen Beurteilung und Risikobewertung. Die zentrale Hypothese unterstellt der Technologie, die überhaupt nur durch die rasanten Fortschritte der Natur- und Ingenieurwissenschaften und damit durch die Aufklärung ermöglicht wurde, eine Unterwanderung der zentralen Prinzipien und Werte der Aufklärung. Zu befürchten ist eine selbstverschuldete Unmündigkeit des Menschen durch die Künstliche Intelligenz. Wesentlich in der Argumentation ist das Aufgeben von menschlicher Autonomie zugunsten einer Technologie, die selbst nicht autonom sein kann, die Verlagerung von Verantwortlichkeiten in einen neu entstandenen rechtsfreien Raum, der Verlust der menschlichen Individualität und letztlich die Preisgabe der Menschenwürde durch den Übergang in ein "Reich ohne Notwendigkeit", aus dem es kein Entkommen gibt. Eine Ethik der Künstlichen Intelligenz muss, so die normative Schlussfolgerung, die Wahrung der menschlichen Autonomie, Verantwortlichkeit, Individualität und Würde in den Vordergrund stellen, sodass ein individueller und kollektiver Rückfall des Menschen in die Unmündigkeit verhindert wird.
Freiwilligenarbeit spielt in der Schweiz wie in vergleichbaren Ländern eine wichtige Rolle für Nonprofit- und öffentliche Organisationen. Betroffen sind die Anbieter von Freiwilligenarbeit vom gesellschaftlichen Wertewandel, den Herausforderungen der Globalisierung, den Chancen und Risiken neuer Technologien, dem Umgang mit demographischen und bildungspolitischen Entwicklungen, mit konkreten Auswirkungen auf die Arbeitstätigkeit der Freiwilligen. Die zunehmende Spezialisierung der Freiwilligenarbeit erfordert zusätzliche Investitionen in Aus- und Weiterbildungsmöglichkeiten, differenzierte Formen der Anerkennung und neue Karrieremuster. Ebenso zeichnet sich eine zunehmende Formalisierung in den personalen und sozialen Rahmenbedingungen ab, mit denen die Anbieter von Freiwilligenarbeit konfrontiert sind. Diese Trends belasten in erster Linie die personal- und finanzschwächeren Organisationen mit limitierten Ressourcen und Wissenspotenzialen. Während die Bedeutung der Freiwilligenarbeit für Gesellschaft, Wirtschaft und NPO gut dokumentiert ist, insbesondere anlässlich des UNO-Jahres der Freiwilligen und der Studien in dessen Folge, geben nur wenige Studien detailliert Auskunft über das Management von Freiwilligen. Da der Begriff Freiwilligenmanagement ebenso unklar und unerforscht ist wie die benötigten Werkzeuge und Instrumente, Strategien und Ansätze und die sich ergebenden Konsequenzen, wird auch die Frage der Relevanz eines Managements von Freiwilligen in der Literatur kontrovers diskutiert. Erste Recherchen brachten Quellen zu Tage, die sich mit unterschiedlichen Aspekten des Managements von NPO befassen. In grossem Umfang liegt Literatur vor zu Organisation, Marketing und Unternehmensführung. Spezifische Publikationen, die sich ganzheitlich mit der systematischen Führung von Freiwilligen befassen, sind dünn gesät. Angesichts der Tatsache, dass sich NPO zunehmend mit einer Professionalisierung der Freiwilligenarbeit auseinandersetzen müssen, besteht hier ein Defizit an theoretischer und praxisorientierter Literatur. Grundsätzlich lässt sich erkennen, dass sich die Wissenschaft allgemein schwer tut, quantitativ- empirische Erkenntnisse über NPO zu gewinnen, da die staatlichen Kontrollen und damit auch die gesetzliche Datenerfassung häufig ungenügend sind. Bis anhin existiert für die Schweiz kein Gesamtbild darüber, wie Freiwilligenmanagement praktiziert wird. Grundsätzlich kann man davon ausgehen, dass NPO den Einsatz von Freiwilligen bewusst führen und managen. Allerdings stützen sie sich dabei eher auf praktische Erfahrung als auf systematisiertes Managementwissen. Angesichts der vorgefundenen Forschungsdefizite möchte die vorliegende Arbeit helfen, das Gesamtverständnis über das Freiwilligenmanagement zu verbessern, sowohl hinsichtlich der vorliegenden Praxis als auch der dazugehörigen Personalpolitik. Im engeren Fokus stehen Notwendigkeit und Entwicklung des Freiwilligenmanagements innerhalb Schweizer NPO und die Frage, wieweit Freiwilligenmanagement relevant ist im Kontext unbezahlter Arbeit sowie die Identifikation relevanter Einflussgrössen. Das Ziel dieser Studie ist es, basierend auf einer Bestandsaufnahme des Freiwilligenmanagements in NPO der Schweiz, einen Überblick zu vermitteln zum Verständnis der Rolle des Freiwilligenmanagements im Kontext der Organisation und der unterschiedlichen Ausprägungen insbesondere der personalen Arbeit innerhalb der unterschiedlichen Typen von NPO. Es wird versucht, verschiedene Ansätze des Freiwilligen-managements zu qualifizieren und grössenklassen-adäquate Empfehlungen zu geben für die Gestaltung effizienter und effektiver Einsätze des Freiwilligenmanagements im Sinne des Auftrags der NPO. Darüber hinaus steht die Entwicklung eines Praxisführers an. Abschliessend wird im engeren Kontext der Arbeit auf offene Forschungsfragen hingewiesen.
Süßwasserökosysteme stellen für menschliche Gesellschaften verschiedene Ökosystemdienstleistungen wie zum Beispiel Trinkwasser oder Fischressourcen bereit. In der modernen Landwirtschaft kommen große Mengen von Agrochemikalien zum Einsatz, die in die Fließgewässer gelangen und dort zur Schädigung des Ökosystems führen können. Die vorliegende Arbeit trägt wichtige Erkenntnisse zur Abschätzung von Exposition und Effekten bei, die aus dem Eintrag von Pestiziden in Fließgewässerökosysteme resultieren können. Dabei wird eine der umfangreichsten Feldstudien zu den Auswirkungen der Pestizidbelastung in kleinen landwirtschaftlichen Fließgewässern vorgestellt. Die Feldstudie wurde an 29 Bächen in zwei Gebieten Finnlands und Frankreichs durchgeführt und umfaßte die Aufnahme der Zusammensetzung der Invertebratengemeinschaften und eines wichtigen Ökosystemprozesses, dem Blattabbau. Des Weiteren wurde ein Pestizidmonitoring für Verbindungen durchgeführt, die nach den Ergebnissen behördlicher Untersuchungen in ökotoxikologisch relevanten Konzentrationen in den Gewässern vorkommen. Nach der Einleitung (Kapitel 1), werden in den Kapiteln 2-4 neue Methoden zur Erfassung der Pestizidbelastung von Fließgewässern vorgestellt und bewertet. Die Ergebnisse aus der Feldstudie zu den Auswirkungen von Pestiziden werden im Kapitel 5 präsentiert. Im 2. Kapitel wird eine neue Methode zur Erfassung von schwebstoffadsorbierten Pestiziden vorgestellt, bei der die Extraktion mit der beschleunigten Lösemittelextraktion (ASE) durchgeführt wurde. Die Methode zeigte gute Ergebnisse bezüglich Exaktheit und Genauigkeit der Wiederfindung bei der Extraktion 10 polarer und semi-polarer Pestizide verschiedener chemischer Klassen. Bei der Anwendung der Methode auf Schwebstoffproben aus den französischen Bächen wurden Konzentrationen gefunden, die auf Invertebraten toxisch wirken könnten. Zusätzlich wurde in dieser Studie die Geeignetheit von deuterierten Standards der Analyten zur Verwendung als interne Standards während der Extraktion, Aufreinigung und Analytik untersucht. Dabei zeigte sich, daß bei deuterierten Standards mit weniger als 10 Deuteriumatomen Unterschiede im Verhalten zur nicht-deuterierten Verbindung auftreten können. Das folgende Kapitel stellt ein Kalibrationsexperiment zur Ermittlung von Sammelraten für den Chemcatcher® Passivsammler mit polarer Empfängerphase vor. Sammelraten für Passivsammler werden benötigt, um nach der Ausbringung in Gewässern zeitlich-gewichtete Durchschnittskonzentrationen (engl. TWA) berechnen zu können. Für den Chemcatcher® bewegten sich die Sammelraten im Bereich von 0.1 bis 0.5 L pro Tag. Das Kalibrationsexperiment ergab zudem, daß der Chemcatcher® ohne diffusionslimitierende Membran für Felduntersuchungen mit bis zu 14 Tagen Expositionszeit geeignet ist. Die ermittelten Sammelraten werden im 4. Kapitel verwendet, um TWAs für die Freilandexposition des Chemcatchers® in den französischen Bächen zu berechnen. Ferner wird die Leistungsfähigkeit des Chemcatchers® mit zwei weiteren Verfahren zur Erfassung von gewässerbezogener Pestizidbelastung verglichen. Dabei zeigte sich, daß die Probenahme der Wasserphase mit dem Chemcatcher® oder einem ereignisbezogenen Wasserprobenehmer bei polaren und semipolaren Pestiziden ein angemesseneres Bild der Belastung liefert als die Probenahme der Schwebstoffphase. Das 5. Kapitel ist den Auswirkungen von Pestiziden gewidmet und präsentiert eine Risikoabschätzung für die Auswirkungen der Pestizideinträge in die französischen und finnischen Gewässer. Zusätzlich werden potentielle Effekte auf den Blattabbau untersucht und die Anwendbarkeit des „Gefährdete Arten“ (SPEcies At Risk - SPEAR) Index für das länderübergreifende Biomonitoring beurteilt. Das Hauptergebnis der Studie ist, daß Pestizide selbst in Konzentrationen, die bisher als unbedeutend angesehen wurden, sowohl die Struktur der Invertebratengemeinschaften verändern als auch den Blattabbau hemmen können. Des Weiteren war der SPEAR Indikator geeignet, Effekte von Pestiziden über verschiedene Regionen hinweg nachzuweisen. Zusammenfassend weist diese Arbeit nach, daß Pestizide einen wichtigen Störfaktor für Fließgewässerökosysteme darstellen können und liefert Methoden zur Expositions- und Effektabschätzung die in zukünftigen Studien Anwendung finden könnten.
Sustainability transitions research proposes fundamental changes of societal systems' organisation to overcome persistent societal challenges, such as climate change or biodiversity loss, and allowing systems to become more sustainable. This thesis adresses an underlying tension in sustainability transitions research: between transitions as an open-ended process of fundamental change and the normative direction of this change: sustainability. In doing so, three themes are in the focus of the research: individual agency, normativity and transdisciplinary collaboration. Thereby, the thesis aims to strengthen process-oriented and potentially transformative approaches to sustainability transition research, in contrast to primarily descriptive-analitical approaches. Transition management as a recent and salient example of transdisciplinary transition research is chosen to provide research framework and application context. Based on conceptual-theoretic, empirical case study and reflexive work, three main results are contributed: First, a psychologically enriched understanding of individual and sustainability related agency in conceptual and empirical understandings of transition management is developed. This builds on two perspectives: a psychologically enriched capability approach as well as the analysis of social effects (social learning, empowerment and social capital development) of transition management to capture sustainability oriented agency increases. As second main result, normative considerations, namely sustainability, are included into transition management on conceptual and empirical levels. Therein, substantive, procedural and intentional aspects of sustainability are combined: Substantive aspects are covered by proposing capabilities, behavioral freedoms to live a valuable life, as normative yardsticks to measure developments. Procedural aspects include a detailed understanding of facilitating a learning journey towards making sustainability meaningful in the local transition management cases and setting up experiments for its realiziation. Intentional aspects are addressed by linking social effects of transition management to awareness, motivations and feelings of responsibility towards sustainability. As a third main result, the transdisciplinary collaboration in transition management of creating an arena as an interactive learning space is conceptualized and explored, as well as the roles of the researchers therein. Key issues of this learning space, the community arena, are drawn out and ideal-type roles and activities of researchers in addressing these issues are proposed and empirically analysed. As synthesis of thesis results, ten principles of sustainability transition management are proposed.
Members of Western organizations differ in various diversity attributes. In response, research aims to provide evidence-based recommendations on how to effectively manage diversity in teams. Within diversity research, the diversity faultlines approach has been particularly fruitful. It considers the impact of the alignment of multiple diversity attributes in teams. Strong diversity faultlines are associated with the emergence of relatively homogeneous subgroups in teams and have an overall negative impact on team processes and outcomes. This dissertation investigates factors that mitigate the detrimental consequences of strong diversity faultlines in teams, namely pro-diversity beliefs. It extends faultline literature beyond the conventional focus on processes and outcomes related to team members by emphasizing the leaders' perspective. The three empirical papers included in this dissertation systematically examine how strong pro-diversity beliefs can help unleashing the positive effects of team diversity despite strong faultlines. The first paper highlights the role of leaders' pro-diversity beliefs in mitigating the negative impact of diversity faultlines on two team processes: perceived cohesion and social loafing. Moreover, it compares the impact of socio-demographic faultlines (based on gender and age) and experience-based faultlines (based on team tenure and education level). Data was collected in a multisource field sample with 217 team members nested in 44 teams and the corresponding leaders. The second paper takes the impact of members' pro-diversity beliefs into account. It examines whether the impact of sociodemographic faultlines on performance is contingent on leaders' and members' pro-diversity beliefs. Moreover, the research group assumed that aggregate LMX would mediate this relationship. In a multisource data set obtained from 41 teams with 219 members and the corresponding leaders working for the German Ministry of Foreign Affairs, the investigators found partial support for their hypotheses. As expected, the impact of strong socio-demographic faultlines on diplomats' performance was least negative when both leaders and members held strong pro-diversity beliefs. The third paper zooms into processes and outcomes related to team leaders. It investigates how leaders' pro-diversity beliefs and their perceptions of members' prodiversity beliefs in teams with strong socio-demographic faultlines impact leaders´ task role assignment, performance expectation, and motivation. The research group conducted two experimental studies with students, one in Germany (N=55) and one in the US (N=134). Findings showed that strong pro-diversity beliefs held and perceived by leaders made them assign task roles that cross-cut rather than aligned with the subgroup structure created by faultlines. Moreover, leaders' perceptions of members' pro-diversity beliefs, but not their own beliefs, had a positive impact on their motivation, mediated by their performance expectation.
Mittlerweile wird auch im Hinblick auf Kindertageseinrichtungen (Kitas) zunehmend über die Verwendung digitaler Medien diskutiert. Die pädagogischen Fachkräfte stoßen dabei auf neue Herausforderungen. Einerseits geht es um die Nutzung digitaler Medien bei der unmittelbaren Arbeit mit den Kindern, andererseits um die Nutzung digitaler Medien für mittelbare Aufgaben wie die Verwaltung oder beispielsweise die Bildungs- und Entwicklungsdokumentation. Der Einsatz digitaler Medien im Rahmen der Bildungs- und Entwicklungsdokumentation in Kindertageseinrichtungen erfolgt nicht einheitlich. Mittlerweile gibt es auch sogenannte Dokumentations-Apps, mit denen Kindertageseinrichtungen ihre Dokumentation ausschließlich digital durchführen können. Im Rahmen dieser Dissertation geht es im Schwerpunkt um eine Auseinandersetzung mit diesen Dokumentations-Apps für Kindertageseinrichtungen. Nach einer Bestandsaufnahme zum Thema Bildungsdokumentation und Entwicklungsdokumentation in Kindertageseinrichtungen, die durch die erste Teiluntersuchung vorgenommen wurde, werden durch die zweite Teiluntersuchung die Sichtweisen von Kita-Leitungen und Erzieherinnen / Erziehern zum Einsatz von Dokumentations-Apps in Kindertageseinrichtungen betrachtet. Dabei werden die Akzeptanz sowie die tatsächliche Nutzung der Dokumentations-Apps von Seiten der pädagogischen Fachkräfte untersucht. Zudem werden Vor- und Nachteile der Verwendung von Dokumentations-Apps aus Sicht der pädagogischen Fachkräfte herausgearbeitet, wobei diese auf die Qualität der Dokumentation bezogen werden. Mithilfe des Rahmenpapiers werden die im Rahmen der zwei Teiluntersuchungen konzipierten drei Beiträge theoretisch eingebettet und in einen übergeordneten Zusammenhang gebracht. Die Ergebnisse werden abschließend im Hinblick auf die Implementierung und Nutzung von Dokumentations-Apps in Kindertageseinrichtungen diskutiert.
Die selektive katalytische Reduktion (SCR) mit Ammoniak als Reduktionsmittel gehört zu den bedeutenden Stickoxidminderungsmaßnahmen bei Personenkraftwagen. Aufgrund des Gefahrenpotentials von Ammoniak wird eine wässrige Harnstofflösung mit einem Harnstoffgehalt von 32,5 % als Reduktionsmittelträger verwendet. Die technischen Herausforderungen im Umgang mit diesem Reduktionsmittelträger liegen in der Kältestabilität mit einem Gefrierpunkt von -11,5°C, der begrenzten Haltbarkeit und der Gefahr zur Bildung von Harnstoffablagerungen in der Abgasanlage. In der Arbeit wird das Ablagerungs- und Alterungsverhalten dieser wässrigen Harnstofflösung unter möglichst realen Bedingungen untersucht. Die Alterung des Reduktionsmittels wird durch verschiedene Fahrzeug- und Umwelteinflüsse während des Betriebes verursacht. Neben der thermischen Alterung als größte Einflussquelle werden ebenfalls tiefe Temperaturen mit Phasenwechseln, die Art der Behälterentgasung, die Fahrdynamik, der Luftdruck und die Hydrolyse hinsichtlich eines Alterungseinflusses untersucht. Auf Basis dieser Daten wird ein empirisches Alterungsmodell entwickelt, was die Bestimmung eines maximalen Alterungszustandes der wässrigen Harnstofflösung erlaubt. Die veränderten chemisch-physikalischen Eigenschaften des gealterten Reduktionsmittels sowie dessen Auswirkungen auf die Emissionen werden in dieser Arbeit bestimmt. Ablagerungen in der Abgasanlage entstehen ausgehend von einer Wandfilmbildung bei niedriger Verdampfungsrate und hoher Verweilzeit des Reduktionsmittels auf kühlen Flächen. Der auskristallisierte Harnstoff wandelt sich je nach Dauer und Ausmaß der thermischen Belastung in Folgeprodukte um. Die Ablagerungsbildung wird im Realbetrieb phänomenologisch beschrieben und charakterisiert. Auf dieser Basis wird das reale Ablagerungsverhalten auf einen Prüfzyklus übertragen und eine geeignete Bewertungsmethode entwickelt. In einer systematischen Untersuchung wird der Einfluss der Wandtemperatur, der Einspritzfrequenz, des Einspritzdrucks, des Einspritzwinkels, der Tropfengröße, der Oberflächenspannung und der Reduktionsmittelalterung experimentell ermittelt. Daraus werden allgemein Möglichkeiten zur Minderung von Harnstoffablagerungen in der Abgasanlage entwickelt und beschrieben.
Audit quality is of crucial importance because it underpins the integrity of financial markets and thus enables complex international transactions. However, despite extensive research on audit quality, the interaction between structures, practices, and behaviors within accounting firms still remains a ´black box´. To open up the ´black box´ I draw on insights from the field of error management which has been highlighted to be central to gain a better understanding of audit quality. In this dissertation, I develop my arguments in three articles that build on each other. In the first paper, I systematically review the literature on the antecedents of audit quality and I suggest future research directions. In the second paper, I take an inductive case study approach to gain an in-depth understanding of error management in accounting firms. The resulting socio-cognitive model of error management informs both the field of error management, as well as the field of audit quality. In the third paper, I examine a crucial component of the socio-cognitive model: the individual. In a two-phase mixed methods study I investigate individual differences in error management and their implications for learning and performance. Taken together, the three articles of this dissertation contribute by providing an innovative approach to our understanding of both error management and audit quality.
Die Innovationsfähigkeit von Unternehmen ist von zentraler Bedeutung für deren Wettbewerbsfähigkeit. Insbesondere kleine und mittelständische Unternehmen (KMU) bedürfen aufgrund ihrer in der Regel vergleichsweise geringen Ressourcennausstattungen und der marktmächtigen Konkurrenz von Großunternehmen einer besonderen Innovationsfähigkeit, um sich am Markt behaupten zu können. Wie mittelständische Unternehmen diese Fähigkeiten jedoch zur Generierung von Innovationen einsetzen, gilt in der Forschung weiterhin als ‚Black Box‘, über die viel zu wenig geforscht wird. Gerade dieser Prozess der Innovationsgenerierung muss jedoch verstanden werden, um Unterschiede in der Innovativität mittelständischer Unternehmen zu erklären. Auf Grundlage einer empirischen Analyse von 41 mittelständischen Innovationssystemen werden in dieser Studie Erfolgsfaktoren der Innovation identifiziert. Anhand von Fallstudien wird erörtert, wie diese Erfolgsfaktoren zusammenwirken und wie diese Faktoren gezielt durch das Management zur Verbesserung der Innovationsfähigkeiten beeinflusst werden können. Mit dieser Dissertation wird nicht nur ein umfassendes Bild von der Entstehung und Konfiguration der Innovationsfähigkeit in mittelständischen Unternehmen gezeichnet, sondern auch die Herausforderungen erörtert, die sich für das Management aus der Steuerung von Innovationsprozessen ergibt. Durch praxisnahe Handlungsempfehlungen bietet diese Dissertation konkrete Lösungsansätze die Innovationsfähigkeit durch eine zielgerichtete Konfiguration nachhaltig zu verbessern und somit einen nachhaltigen Wettbewerbsvorteil zu erzielen.
Die Arbeit thematisiert die Erklärung der Wahrnehmung von Produkt-, Marken- und Preiseigenschaften und die Bildung von Produkt- und Markenpräferenzen bei Auswahlentscheidungen von Urlaubsreisenden in Bezug auf die Urlaubspauschalreise und deren Einzelleistungsträger Urlaubsdestination, Reiseveranstalter und Hotel mit Hilfe des Involvementkonzeptes. Im theoretischen Teil der Arbeit werden aufgrund konzeptioneller Vorüberlegungen und einer Bewertung bestehender Involvement-Konzepte und Involvementmessinstrumente die konzeptionellen Anforderungen an ein Involvement-Messmodell formuliert. Zum Abschluss des Theorieteils wird ein allgemeines theoretisches Modell, das Involvement-Präferenz-Modell entwickelt. Ziel des Erklärungsmodells ist die Erfassung und Systematisierung der relevanten Faktoren, die das Entscheidungsverhalten von Urlaubern abbilden unter Fokussierung auf das Involvement als zentraler Steuerungsgröße. Aufgrund der herausgehobenen Stellung des Reiseveranstalters bei der Buchungsentscheidung wurde dieser in den Mittelpunkt der empirischen Analyse gestellt. Dabei galt es insbesondere kausale Abhängigkeiten zwischen den Ursachen, Formen und Konsequenzen von Involvement zu untersuchen. Die Auswertung wurde mit LISREL durchgeführt. Die Untersuchung hat gezeigt, dass unterschiedliche Involvementzustände distinkte Wahrnehmungsmuster in Bezug auf Produktqualität, Marke und Preis erzeugen und damit Form und Intensität des Entscheiderinvolvements einen kausalen Einfluss auf die Wahrnehmungsstrukturen von Urlaubsentscheidern im Hinblick auf die Wahrnehmung von Produkt-, Marken- und Preiseigenschaften von Reiseveranstaltern besitzen. Die Implikationen für das touristische Marketing und die Einsatzmöglichkeiten des Modells für die Konsumentenforschung werden zum Abschluss der Arbeit diskutiert.
Die Verwendung lokaltypischer Baumaterialien gilt als ein wichtiges prägendes Merkmal von Städten mit historischer Bausubstanz. Für Norddeutschland ist es i. d. R. der sichtbar verbaute rote Backstein, dem diese prägende Wirkung zugeschrieben wird. Mit Begriffen wie ›Backsteingotik‹ oder ›Backsteinstadt‹ wird die herausragende Bedeutung des Materials für Architektur und Stadtbild noch betont. Die niedersächsische Stadt Lüneburg ist eine solche ›Backsteinstadt‹. Backsteine wurden hier schon im Mittelalter hergestellt und verbaut; keine Fassadengestaltung wird auch bei Neubauten als so selbstverständlich angesehen wie die aus rotem Ziegelmaterial. Die vorliegende Arbeit geht der Frage nach, warum das Material Backstein für das Stadtbild von Lüneburg eine so zentrale Rolle spielt. Es wird untersucht inwieweit sich dieses Stadtbild als logische Folge der Nutzung lokal vorhandener Rohstoffe erklären lässt und in welchem Maß weitere Umstände Einfluss auf die Bausubstanz und das Bild der Stadt hatten bzw. haben. Um sowohl rohstoffgeologische, technik- und bauhistorische Aspekte als auch den zeitspezifischen Wandel gesellschaftlicher Aneignungsprozesse und deren Auswirkungen in die Untersuchungen einbeziehen zu können, wird ein bestehender kulturgeographisch-konstruktivistischer Ansatz aus der Landschaftsforschung um eine historisch-geographische Perspektive erweitert und auf den Begriff des Stadtbilds übertragen. Diese Herangehensweise ermöglicht es, bisher ungeklärte Fragen zum Lüneburger Backstein zu beantworten und übergeordnete Zusammenhänge zu verdeutlichen. Darüber hinaus wird klar, wie unauflösbar dicht die physisch-materielle Dimension der Backsteinstadt mit der Historizität ihrer sozialen Konstruktion verwoben ist.
This dissertation includes an introduction and five empirical papers focusing on the educational and career decision-making process of individuals in Germany. The five papers embrace different determinants of educational and career decisions including school performance, social background, leisure activities as well as professional expectations, and contribute to the existing literature in this research area. Chapter 2 of this dissertation begins by analysing the nexus between students’ time allocation and school performance in terms of grades and satisfaction with their own performance in mathematics, the German language and a first foreign language, as well as overall achievement. This chapter looks at the heterogeneity of three important extracurricular activities: student jobs, sports and participation in music. Moreover, the heterogeneity of each activity is addressed by accounting for different types of the particular activity and differences in the number of years the activity has been pursued. For this purpose, data from the German SOEP, as a representative panel survey of private households and people in Germany, in particular cross-sectional survey data of 3388 students who are about 17 years old and enrolled in a German secondary school, were used. The main findings are that having a job as a student is negatively correlated with school performance, whereas participation in sports and music is positively correlated. However, the results reveal heterogeneity in each activity, especially with respect to intensity. Chapter 3 addresses the concrete post-school decision of school students, in particular whether to study or to enter the German VET system (Vocational Education and Training). It focuses on individual risk preferences and the social background of individuals and how these determinants affect the ultimate decision to enrol in university or to start an apprenticeship given the same level of qualification. For the empirical approach data from the German SOEP were used, in particular information on individuals' educational decisions between 2007 and 2013. The results indicate that (i) individual risk preferences do not have an overall effect on the real transition; (ii) privileged individuals are more likely to take up higher education; and (iii) compared to highly educated parents, parents without an academic background are less likely to guide their children into tertiary education, regardless of how much they support their children with their school work. Chapter 4 deals with the reconsideration of educational decisions in terms of early contract cancellations in VET. In particular, the effects of a second job on the intention to cancel a VET contract early are analysed for apprentices in Germany. For the empirical approach the representative German firm-level study "BIBB Survey Vocational Training from the Trainee's Point of View 2008", conducted by the Federal Institute for Vocational Education and Training (BIBB), is used. The survey contains 5901 apprentices that were interviewed during their second year of apprenticeship (205 schools, 340 classes, and 15 common occupations). Furthermore, it includes the design, procedures, basic conditions, and quality criteria of apprenticeships. The applied probit regressions show a higher intention to quit if apprentices require a secondary job to cover their living costs. In Chapter 5, new data on 191 apprentices from a vocational school, located in a northern German federal state, are used to validate the empirical results of Chapter 4. This chapter presents new insights into secondary-job-related burdens during apprenticeship. Due to limitations in the data, the applied empirical approach in Chapter 4 lacks to analyse how holding multiple jobs increases the intention to leave an apprenticeship early. Therefore, Chapter 5 includes the investigations of burdens related to the second job. The results indicate a lower intention to quit the apprenticeship if an apprentice holds a second job to cover living costs. However, secondary jobs are linked to lower quality of training, which, on the other hand, increases the intention to leave the apprenticeship early. Furthermore, the probability of secondary-job-related burdens increases with the number of working hours. Chapter 6 concludes the thesis by investigating subjective determinants of early contract cancellations in VET. It examines ten questions on what apprentices want to achieve and how unfulfilled expectations affect the intention to leave the apprenticeship early. The findings of this investigation contributes to the existing research on early contract cancellation. The questions considered include information on the performance, personal development, career development and prospects or position in society and their meaning to apprentices. For the research approach, the "BIBB Survey Vocational Training from the Trainee's Point of View 2008" is considered again. The probit and ordered probit regressions applied show significant effects of job characteristics that represent job security. The expectation of being retained after an apprenticeship and the encouragement to consistently train further decrease the intention to leave the apprenticeship early. Furthermore, women appear to be more affected by job security signals than men, but they also sort more often into occupations with lower retention probabilities. Consequently, this result may be an indication of occupational segregation rather than a sign of differences between sexes.
Die Arbeit analysiert den Einfluss von Arbeitsmarktregimen auf das Sparverhalten privater Haushalte in Deutschland und Großbritannien aus einer vergleichenden Perspektive. Im Zentrum steht dabei die Frage, ob das Sparvermögen abhängig beschäftigter Personen durch ihre Angst vor Arbeitslosigkeit beeinflusst wird. Die Untersuchung widmet sich dem Einfluss von Institutionen auf individuelles Verhalten in unterschiedlichen nationalen Kontexten: geringere Dynamik des deutschen Arbeitsmarktes – operationalisiert über die durchschnittliche Verweildauer in Arbeitslosigkeit – und entsprechend höhere individuelle Angst vor Arbeitslosigkeit tragen demnach zur Erklärung bei, warum die aggregierten Sparquoten privater Haushalte in kontinental-europäischen deutlich höher sind als in angelsächsischen Wohlfahrtsstaaten. Die theoretische Fundierung auf der Mikroebene liefert ein Buffer-Stock Saving-Modell, wonach sich Individuen gegen Einkommensvolatilität durch das Anhäufen von Sparvermögen absichern (Vorsichtssparen). Anhand von Panel-Daten abhängig beschäftigter Personen in Deutschland (SOEP) und Großbritannien (BHPS) ergibt sich unter Kontrolle für Konsumpräferenzen und weitere Einflussfaktoren in Deutschland bei Einverdiener-Haushalten ein Vorsichtsmotiv, das durchschnittlich einem Drittel des liquiden Vermögens entspricht, wohingegen sich kein vergleichbarer Effekt in Großbritannien zweigt.