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Hochtemperatur-Aquiferwärmespeicher erleichtern Wärmesystemen durch eine saisonale Lastverschiebung die Erschließung und Integration von erneuerbaren Wärmequellen. Ein mittleres Temperaturniveau von > 50 Grad Celsius ermöglicht zumeist eine direkte Entladung ohne einen anschließenden Temperaturhub über eine Wärmepumpe. Aufgrund der thermischen Trägheit von ATES-Systemen ist die Berücksichtigung von Lastfalländerungen durch jährlich variierende Lastprofile besonders in der Einschwingphase sinnvoll. Da es bis zu 20 Jahre dauern kann, bis der Aquifer einen quasistationären Zustand erreicht, konnte in Langzeitstudien ein großer Einfluss von unterschiedlichen Lastprofilen auf energetische und finanzielle Simulationsergebnisse nachgewiesen werden. Zur Verbesserung der Investitionsplanung wurde ein Verfahren entwickelt, das sowohl die Prognosefähigkeit als auch die Prognosegenauigkeit von Energiesystem- und Wirtschaftlichkeitsanalysen erhöht, indem über einen wahrscheinlichkeitsbasierten Ansatz (Monte-Carlo-Temperaturschätzung) Normalverteilungsfunktionen für gewünschte Auswertungsgrößen (z.B. Kapitalwert) abgeleitet werden können. Aus 2000 Simulationsjahren wurde über konzeptspezifische Verteilungsfunktionen der wahrscheinlichste Eintrittsfall abgeleitet und zu einem repräsentativen Szenario aggregiert. Das aggregierte Szenario mündet in ein konzeptspezifisches Gleichungssystem, das mit den Freiheitsgraden Energiepreise, Kalkulationszinssatz und Förderanteil gelöst wird. Im Gegensatz zu der etablierten Methode, die Wirtschaftlichkeitsberechnung im Anschluss an eine energetische Systemsimulation anzuhängen, wurde in dieser Arbeit ein holistisches Modell in TRNSYS entwickelt, das für jeden Simulationszeitschritt simultan Energie- und Zahlungsströme berechnet. In dem Modell konnten Verbesserungen in der Prognosegenauigkeit um den Faktor 20 nachgewiesen werden. Mit dem neuen Verfahren kann die Frage der Wirtschaftlichkeit nicht nur mit ja oder nein beantwortet werden, sondern zusätzlich mit der jeweiligen Eintrittswahrscheinlichkeit belegt werden.
The dissertation analyzes the role of large banks in the context of financial (in)stability. Based on the underlying “too big to fail”-problem (TBTF), the three included papers investigate the reasons for the instability of banking systems on a national and international level. Already in advance, but at least since the years 2007/2008 with the escalation of the financial crisis, especially large banks are under critical supervision of regulators and the society. There exist numerous aspects that should to be taken into account when addressing TBTF which complicates the finding of a solution to the problem. In particular, the thesis investigates three major issues in this context: 1.) The contribution of the size of a bank to the development of financial crises or the exposure of large banks to systematic risk and contagious spillovers. 2) The spillover effects from one banking system to another and the importance of banks’ foreign asset holdings for the transmission of sovereign risk on foreign banks. 3.) The impact of the degree of competition in the German banking market on the stability of the banking system.
The process perspective provides a unifying framework that has substantially contributed to our understanding of entrepreneurship. However, much of the research up to now has neglected this process oriented conception of entrepreneurship. There is therefore a need for studies that take the inherent dynamic processes into account and analyze the underlying mechanisms when researching entrepreneurship. This dissertation aims to improve our understanding of the entrepreneurial process. Specifically, this dissertation focuses on new venture creation and the processes of sustainable opportunity identification and opportunity deviation. Chapter 1 provides a general introduction that highlights the theoretical contributions of this dissertation and gives an overview over the conducted studies. Chapter 2 argues for a process model of entrepreneurship that places entrepreneurs and their actions center stage. The model combines different perspectives and levels of analysis and provides an integrative framework for researching new venture creation. In chapter 3 we establish and test a theoretical model of sustainable opportunity identification. The chapter explains how younger generations identify sustainable opportunities. The findings indicate that sustainable opportunity identification is a process with two transitions from problem to solution identification and from solution identification to sustainable opportunity identification. These transitions are contingent on awareness of consequences and entrepreneurial attitude. Chapter 4 offers insights into how deviation from the original opportunity increases the performance of entrepreneurial teams. The findings indicate that entrepreneurial teams with a high level of error orientation set themselves higher goals when deviating from their original opportunity. Higher goals then lead to higher team performance. Chapter 5 summarizes the overall findings and outlines the general theoretical and practical implications. Each chapter thus contributes to the process perspective by focusing on how different phases of the entrepreneurial process unfold and develop over time. Thereby, this dissertation advances our understanding of entrepreneurship as a process.
Die Öffnung der Universitäten in Deutschland für nicht-traditionelle Zielgruppen schafft neue Bildungsmöglichkeiten für Studienanwärterinnen und Studienanwärter mit beruflichen Vorbildungen. Eine entscheidende Funktion kommt hierbei den außeruniversitär akkumulierten Berufserfahrungen zu. Diese lassen sich mittlerweile auf Studienleistungen anrechnen. Vor dieser Ausgangslage werden Berufserfahrungen als ein in Berufsausbildung und Berufstätigkeit angeeignetes und akkumuliertes berufliches Kapital verstanden. Berufliches Kapital wird verstärkt von dieser neuen und nicht homogenen Gruppe zukünftiger Studierender als Zugangsmöglichkeit zur Universität genutzt. Zudem bieten Universitäten in wachsendem Umfang weiterbildende Studiengänge an, die den Erwerb von beruflichem Kapital synchron zum Erwerb von universitärem akademischem Kapital ermöglichen. Das Auftauchen neuer, nicht-traditioneller Studierendengruppen führt zu Veränderungen im System der Universität, auf welche die bereits etablierten Aktuere in diesem Feld, insbesondere die akademischen Mitarbeitenden, reagieren müssen. Die Dissertation untersuchte mit Hilfe eines Mixed-Method-Designs habitualisierte Verhaltens-, Denk- und Wahrnehmungsmuster von akademischen Hochschulmitarbeitenden im Hinblick auf Studierende mit beruflichem Kapital. Es wurde zum einen eine quantitative Befragung von akademischen Mitarbeitenden an einer Universität und zum anderen eine explorative qualitative Interviewstudie über akademische Hochschullehrende an insgesamt sechs deutschen Universitäten durchgeführt. Die Universiäten und Fächer in beiden Studien unterschieden sich in dem Grad, in dem die Hochschulöffnung bereits vorangeschritten war. In beiden Studien wurden geschlechtsbezogene, fachspezifische und organisationale Unterschiede analysiert, die Rückschlüsse auf den Habitus der Hochschulmitarbeitenden und deren Blick auf die (angehenden) Studierenden mit beruflichem Kapital ermöglichen. Die Analyse konnte in beiden Studien aufzeigen, dass akademische Hochschulmitarbeitende mehrheitlich Einstellungen geäußert haben, die zwischen Ambivalenz und einer ausgesprochen inklusiven Haltung gegenüber der Hochschulöffnung zu verorten sind. Durch die quantitative Studie ließ sich ermitteln, dass weibliche Befragte und Angehörige der sogennanten weichen Wissenschaften, hinsichtlich der Hochschulöffnung solche Positionen einnahmen, die durch ein hohes bzw. ein Höchstmaß an Inklusion gekennzeichnet sind. Die Auswertung der qualitativen Analyse konnte zeigen, dass Befragte, die ihrerseits offen auf die neuen Studierendengruppen zugehen, überwiegend auch eine konstruktivistische Lehr-Lern-Überzeugung haben und eine verstärkte Anwendungsorientierung in der Lehre praktizieren, organisationale Faktoren hatten hingegen einen vernachlässigbaren Einfluss auf die Einstellungen und den Habitus der untersuchten Wissenschaftlerinnen und Wissenschaftler.
Die Agenda 2030 der Vereinten Nationen und diverse daraus abgeleitete Nachhaltigkeitsstrategien wie beispielsweise die Deutsche Nachhaltigkeitsstrategie (Neuauflage 2016) 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 soll aus der Zusammenführung von Theorie und Praxis die Natur des inhaltlichen politischen Strategiebegriffs erforscht werden und zum anderen soll darauf aufbauend ein praxis- und erfahrungsorientiertes Anwendungsmodell entwickelt werden, 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 zeigen wird - eine simple Übertragung strategischer Allgemeinplätze aus Militär und Ökonomie von vornherein zum Scheitern verurteilt.
Lehrerinnen und Lehrer benötigen professionelle Kompetenzen um den spezifischen Bedürfnissen von mehrsprachigen Schülerinnen und Schülern gerecht zu werden. Gelegenheiten zum Kompetenzerwerb im Bereich sprachlicher Heterogenität sind daher unerlässlich in der Lehramtsausbildung. Um angemessene Lerngelegenheiten identifizieren und evaluieren zu können, werden in dieser Arbeit zum einen die kognitiven und motivational-affektiven Facetten professioneller Kompetenz für den Bereich Sprachliche Heterogenität modelliert. Zum anderen werden ein Testinstrument zur Messung der kognitiven Facetten (DaZKom-Test) sowie ein Fragebogen zur Erfassung motivational-affektiver Facetten vorgestellt. Die vorliegende Arbeit informiert über die Validierung der Testwertinterpretation des DaZKom-Tests, die Identifizierung von Typen bezogen auf ihre Überzeugungen zu Mehrsprachigkeit in der Schule bei angehenden Lehrkräften, und stellt ein erweitertes theoretisches Kompetenzmodell vor, welches einen internationalen Vergleich von Kompetenzen (angehender) Lehrkräfte ermöglicht. Anhand der gewonnenen Ergebnisse dieser Arbeit ist ein besseres Verständnis der Lehramtsausbildung in Bezug auf den Umgang mit mehrsprachigen Schülerinnen und Schülern möglich.
Restoration and management of abandoned, dry continental heathland and sandy grassland communities
(2018)
Land-use changes and long-term abandonment are main drivers that change ecosystem functioning and cause biodiversity loss of many semi-natural habitats, such as heathlands and grasslands. Traditional management measures such as low-intensity grazing created these semi-open landscapes and maintained a high species richness. However, from the middle of the 19th century onwards, traditional management practices began to decline due to socio-economic changes, and large areas of heathlands and grasslands were subjected to succession and reverted to woodland. Nowadays, dry heathlands as well as dry sandy grasslands are recognized as being of high conservation value and classified as ´habitats of community interest´ (´European dry heaths´, habitat code 4030; ´Xeric sand calcareous grasslands´, habitat code *6120). Whereas heathlands in the Atlantic biogeographical region have been in the centre of interest, dry heathland communities in the Continental biogeographical region have been widely neglected, even though they comprise 30 percent of all dry heaths as well as 89 percent of all dry sandy grasslands, respectively, in Europe. Thereby, the conservation status of both habitat types is listed as unfavourable-bad across the Continental biogeographical region. Surprisingly, no detailed studies are available on cost-efficient and sustainable restoration and management schemes to successfully restore and maintain highly degraded, long-abandoned Continental heaths and sandy grasslands, and thus, to counteract the poor conservation status of the habitat types. This shows the great need for research for the Continental biogeographical region (chapter I). Thus, the present thesis provides substantial knowledge about the population dynamics of the key plant species of dry heaths Calluna vulgaris (L.) HULL (henceforth referred to as Calluna) by investigating key processes in the biology of the species as well as about the restoration and management of long-abandoned, dry Continental heathland and sandy grassland communities. In order to better understand the process of successful Continental heathland restoration, I analysed the reproductive potential (seed production, soil seed bank, and germination ability of seeds) of degenerate Calluna stands as well as the effects of single and combined management options on the generative rejuvenation (i.e., recruitment and survival) of Calluna (chapter II). The results are based on a comprehensive three-year field experiment including the management options year-round, low-intensity cattle and horse grazing, one-time mowing and one-time shallow soil disturbances combined with greenhouse investigations on the soil seed bank content and germination ability of Calluna seeds. The results showed that even after long-term abandonment, seed production of degenerate Calluna stands and the germination ability of seeds proved to be high, being similar to Atlantic heathlands, whereas the soil seed bank is considerably reduced probably due to the dry conditions in the Continental region. In addition, low-intensity grazing with free-ranging robust breeds and the combination with one-time mowing at the beginning of the restoration process is an effective means of supporting the generative rejuvenation of this key plant species in degraded Continental heaths. The second study of this thesis (chapter III) focussed on the first-year establishment of Calluna in managed and unmanaged dry heaths and heaths in mosaics with dry sandy grasslands. The germination ability of seeds of different life-history phases of Calluna was analysed to determine if the predominance of the late life-history phase restricts the rejuvenation process of this key plant species. In addition, beside effects of management measures (year-round, low-intensity grazing, one-time mowing, one-time shallow soil disturbances) I analysed the most important safe site conditions that possibly influenced the germination and the first-year survival of Calluna. The results of the study combine field experiments with growth chamber investigations. I found that life-history phase of Calluna did not significantly affect seed germination and thus, the predominance of the degenerate life-history phase does not restrict the rejuvenation process. In addition, the results of my study revealed that grazing and thus trampling intensity must be temporarily and locally enhanced at the beginning of the restoration process of highly degraded heaths to increase safe site availability for successful Calluna establishment. Thereby, shadowing is the most important safe site condition that limit Calluna recruitment and survival in the first year in both degraded heaths as well as in mosaics with sandy grasslands, since seedlings receiving full sunlight die significantly more frequently than slightly or fully shaded seedlings. In the third study (chapter IV), I investigated the impacts of year-round low-intensity cattle and horse grazing on the development of the highly competitive grass Calamagrostis epigejos (henceforth referred to as Calamagrostis), as well as the vegetation structure and plant species richness of long-abandoned but nutrient-poor dry heathland and sandy grassland communities, their mosaics and Calamagrostis stands. Finally, I assessed the local conservation status of the habitat types after seven years of grazing in comparison to long-abandoned sites. The results are based on a comprehensive field study on two spatial scales (plot-level: 25 square meters, macroplot-level: 1 ha). I found that grazing successfully reduced the coverage and prevented the further spread of Calamagrostis, while simultaneously maintained or improved characteristic species richness and vegetation structure across the different nutrient-poor vegetation types over time, and thus enhanced the local conservation status of habitat types of community interest. In conclusion, the results of my studies considerably improved the understanding of dry, Continental heathland and sandy grassland restoration and management. They provide evidence that even after long-term management abandonment, year-round low-intensity cattle and horse grazing is a suitable management tool for restoring, maintaining and even improving nutrient-poor heathland and sandy grassland communities. However, at the beginning of the restoration process, additional management measures are necessary to faster restore abandoned habitats, especially highly degraded heaths.
The German energy system is under transformation. The so-called Energiewende (in English, Energy turn) relies, among other things, on renewable energies for building a more sustainable energy system. Regions (Landkreise) are one relevant level where different administrative bodies make decisions and plans both for the implementation and for the use of renewable energies. However, in order to realize the goals of the Energiewende, developments in the wider society are necessary. This is why, scientific research can and should foster such developments with more research on the social aspects of energy-related topics. The present work contributes to the understanding of transition processes towards a sustainable use of regional renewable energy by focusing on the role of contextual conditions, practical experiences, and temporal dynamics in the implementation and use of renewable energy in German regions. In this way, this work wants to contribute fostering the development of regional energy transition strategies for the realization of the Energiewende. The conceptual background for this piece of transformation research lies in three bodies of literature dealing respectively with transitions of socio-technical systems, transformations of socioecological systems, and time ecology. From a critical engagement with this literature, three main results have emerged. First, an evidence-based, spatially distinct analysis of contextual conditions for the use of renewable energy in all German regions has resulted in the identification of nine types of regions, so-called energy context types. Second, empirical research on practices in regional settings learned from the knowhow of actors from regional administration has shown that political and economic conditions are crucial as well as that process management, exchange, and learning are helpful for renewable energy implementation. Third, conceptual work about a deeper understanding of the temporal dimensions of transformation processes has made it possible to point out a three-step approach to include temporal dynamics into sustainability transformations management - the time-in-transformations-approach. The literature suggests that regions need to be treated individually; but developing an energy transition strategy for each region individually would be extremely resource intensive. Overall, my work outlines a compromise for a more efficient approach towards regional energy transition strategies which still considers the individuality of regions. As a result, I suggest to develop generic regional energy transition strategies that are adapted to each of the nine energy context types of German regions, that include the experiences of practitioners, and that consider temporal dynamics of transformation processes. Transdisciplinary research is a promising approach to meet many of the challenges for the realization of the Energiewende. A transdisciplinary steering board on the national level could create generic regional energy transition strategies that guide the energy transition and give clear goals and orientation for the realization of policies on the lower levels. On the regional level, these strategies would need to be adapted with regard to each region´s situation. Relying on the results of my research, I conclude that this could also be informed through transdisciplinary processes.
Social insects like honeybees (Apis mellifera) and stingless bees (Apidae: Meliponini) face a relatively high risk to be attacked by pests and pathogens. To decrease the risk of infection, in addition to an innate immune system, these species have evolved various cooperative defense mechanisms such as hygienic behavior or allo-grooming, which contribute to the overall health of the colonies and are therefore also referred to as social immunity. The collection and use of plant resin is another important strategy of social immunity. Resin is a sticky, often aromatic substance with antimicrobial and deterrent properties secreted by plants for protection of the vegetative tissue. Honeybees and stingless bees take advantage of these properties by using resins for nest construction (often mixtures of resin and wax called “propolis” or “cerumen”) and as defense against pests and pathogens. Plant resins, thus, play a crucial role for the ecology of these species and are an important resource for them. Nevertheless, how bees exploit available resin sources and if resin collection can protect colonies from diseases received comparatively little attention in the past. Therefore the aim of this thesis is to provide new insights into the plant origin and significance as well as the influence of resin resource diversity on bee colony health. Resource use and availability form fundamental prerequisites, having decisive influence on the viability of individuals and maintenance of populations. Information on the resources required by a species is thus important to effectively promote and preserve it. For honeybees (A. mellifera) in temperate regions, precise information about which resin sources they use is largely lacking. By chemical comparing bee-collected resins and tree resins, I traced back the resin sources used by individual bees. Results show that honeybees collect distinct resin types that are related to different tree species (several poplar species: Populus balsamifera, P. xcanadensis; Betula alba; Aesculus hippocastanum; several poplar species). With this study I provided the first evidence, that A. mellifera in temperate regions use a variety of different tree species as resin sources and, moreover, show preferences for specific resin sources. Maintenance of colony health is probably one of the major purposes of resin collection. Nevertheless, studies investigating the benefits of resins at the colony level are rare and there are only few evidences on the effects of raw propolis (unlike commonly used ethanol extracts) on colony health. For this reason, I conducted an experimental field study in which I investigated whether propolis, as it is naturally deposited in the nests, can protect honeybee colonies against some of the most important pathogens (Varroa destructor mite, Deformed Wing Virus). The results of this study showed that propolis in (semi-) natural conditions can increase the disease resistance of honeybee colonies, underscoring the importance of resins for honeybee health. Resin collection by stingless bees is comparatively well studied and it is known that these species commonly forage on a variety of different plant species. To increase knowledge on whether and how bees may profit from a diversity of resin resources, I tested how the protective function of a resin varied among different sources (and their mixtures) and various potential aggressors (predators, parasites and pathogens). The results of this study revealed that resins from different trees vary in their effectivity against different target organisms. Moreover, resin blends were more effective than some of the individual resins, suggesting that bees can benefit from a variety of resin resources. In summary, honeybees in temperate regions, similar to tropical stingless bees, use a variety of different tree species as resin sources. Because resins from different tree species varied in their protective function, this indicates that bees can profit from a variety of different resins/resin sources by improving the defense against diverse pests and pathogens. Conversely, the lack of resin had a negative impact on the disease resistance of colonies. Consequently, availability as well as the variety of suitable resin sources is of great importance for the health of bees. In addition to nectar and pollen, resin, as a further important resource, should therefore find more attention in beekeeping. Resin collection as the natural disease defense of bees should find more respect in beekeeping praxis and should be more strongly included in future consideration on how to promote bee colony health.
Organophosphorus flame retardants and plasticizers (OPEs) have been utilized for decades as plasticizers and, to a lesser extent, as flame retardants in various consumer products to improve their material properties. With the restriction and ban of the widely used brominated diphenyl ethers (PBDEs) by, ultimately, the Stockholm Convention due to their adverse effects on humans and the environment, the use of OPEs as replacements has increased rapidly. However, the potential adverse properties, environmental distribution and fate of OPEs are insufficiently understood. The research presented in this thesis investigated the occurrence, distribution and transport of OPEs with a focus on the coastal and estuarine environment. Due to the wide range of physicochemical properties of OPEs, the environmental fate and behaviour of OPEs was investigated over a range of compartments, starting from the atmospheric occurrence to the aquatic phase and the behaviour in sediments. The aim was to gather information on the OPE contamination situation in the coastal and estuarine environments, to identify specific contamination patterns for source assessment and to investigate the distribution behaviour of OPEs between gas- and particle-phases to evaluate their environmental transport mechanism. To achieve these scientific goals, sensitive and robust chemical analytical methods for the detection and quantification of OPEs in a variety of environmental samples using gas-chromatography coupled with tandem mass spectrometry were developed. Water samples were removed along the Elbe and Rhine Rivers to test the hypothesis of whether specific point sources, such as wastewater treatment plants, are the major input pathways for OPE contamination in rivers. A total of 65 water samples, including an intensive measurement campaign during the flood event in 2013 at the Elbe, was taken and analysed for OPEs. No obvious point sources were identified along either of the rivers analysed. No significant increase or decrease in the OPE concentrations or a change in patterns were observed over a transect of over 300 km at the Elbe, with an increase in water discharge of 2.5. This finding suggested that the OPE input in large rivers is primarily driven by diffuse sources, such as surface runoff, or by minor point sources rather than local point sources. To examine the specific pattern of OPE contamination in individual rivers and estuaries, 37 sediment samples from 8 rivers in Europe and China were analysed. With this analytical data, a fingerprint analysis of the OPE patterns identified could be conducted. All the rivers investigated in Europe displayed a very similar fingerprint, which can be explained by the common European market with consistent legislative regulations. In contrast, the fingerprint from China differed significantly from the one in Europe. For example, in China, the OPE restricted in Europe, Tris(2-chloroethly)phosphate, was found to be one of the major OPE components, while Tris(2-butoxyethyl) phosphate, a major compound in Europe, was negligible in China. The investigation showed that the fingerprinting analysis is a useful tool to identify different regions or characterize specific rivers regarding their OPE contamination. In addition, it could be shown that legislative restriction and processes have an impact on local or even EU-wide contamination patterns. At a coastal site next to the German city of Büsum, 58 air samples were taken over one year. Using the newly developed analytical method, it was possible to analyse the gas, as well as the particle phase, of the samples collected with very low detection limits for OPEs. In contrast to expectations, no annual trend in OPE concentrations, phase distributions or patterns was observed, but the investigation of the phase distribution challenged the previous scientific consensus that OPEs occur as primarily bound to particles in the atmosphere. Several compounds were detected in significant amounts in the gas phase. To validate these novel results, a model analysis based on the chemical properties of OPEs was conducted using three different phase distribution models. The results from the environmental data were strongly supported by the simulations, and the formal knowledge could be refuted. Consequently, the atmospheric transport assumptions and estimations about the long-range transport of OPEs have to be reassessed because compounds in the gas phase undergo other types of transport degradation and elimination mechanisms than particle-boundones. The novel findings presented in this thesis challenged an important aspect regarding the perceived scientific knowledge about the behaviour of OPEs in the environment and call on the scientific community to reassess the environmental behaviour of OPEs. The insights presented on the patterns highlight the impact of environmental policies and regulatory mechanisms to work towards the final goal of a good environmental status and the avoidance of adverse effects of discarded chemicals on humans and the environment.
Netzwerkbildung im Musiksektor Niedersachsen : Funktionsweisen und Mechanismen sozialer Formationen
(2018)
In Niedersachsen existiert eine florierende, ausdifferenzierte kulturelle Szene. Vor allem im Musikbereich sind zahlreiche, teilweise international agierende Initiativen und einige kleinere und mittlere Unternehmen wie auch Solokünstler aktiv, die in einem regen Austausch miteinander stehen. Diese Akteure treten in der Regel mit der Erwartung einer positiven Auswirkung und Nutzensteigerung einem Netzwerk bei. Selten wird jedoch hinterfragt oder im Anschluss evaluiert, inwiefern das jeweilige Netzwerk zur positiven Verstärkung der Einzelakteure, im ökonomischen wie auch im sozialen oder kulturellen Sinne geführt hat, beziehungsweise inwieweit Netzwerkbildungen auch zu negativen Effekten für ihre Akteure führen können. In dieser Dissertation wird mit qualitativen Methoden und auf theoretischer Basis der Relationalen Soziologie die Situation in Bezug auf Netzwerkbildungen im Musiksektor von Niedersachsen analysiert. Dies geschieht vor den Fragen, wer die Akteure in Niedersachsen sind, und welchen Funktionsweisen und Mechanismen ihre Vernetzungsbestrebungen unterliegen. Ferner werden die Interaktionen zwischen sozialen Akteuren und institutioneller Kulturarbeit im Musiksektor dargestellt und aufgezeigt, welche Prozesse in diesem Musiknetzwerk unter dem Einfluss institutioneller Strukturen ablaufen.
The emission of anthropogenic trace substances into the aquatic environment continuously poses challenges to water suppliers. The contamination of raw waters with organic trace substances requires complex water treatment processes to secure drinking water quality. The routine monitoring of these raw waters as well as the behavior and fate of organic trace substances during different treatment processes is of great interest to recognize and counter potential dangers at an early stage. Chromatographic separation techniques coupled to triple quadrupole mass spectrometers are conventionally used for the reliable monitoring of traces of known polar substances. However, such analytical techniques usually fail to recognize unknown compounds. This weakness presents a serious restriction with regard to the monitoring of treatment processes, since transformation products are often not - or not sufficiently - characterized and are thus only detected sporadically. Non-target screening using liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) allows the detection of thousands of compounds within a single run and covers known as well as unknown substances. Compared to the established analytical techniques, this is a decisive advantage for the monitoring of raw and process waters during water treatment. While the analytical technique LC-HRMS has undergone significant developments in recent years, the algorithms for data processing reveal clear weaknesses. This dissertation therefore deals with reliable processing strategies for LC-HRMS data. The first part of this work seeks to highlight the problematics of false positive and false negative findings. Based on repeated measurements, various strategies of data processing were assessed with regard to the repeatability of the results. To ensure that real peaks were barely or not removed by the filtering procedure, samples were spiked with isotope-labeled standards. The results emphasize that the processing of sample triplicates results in sufficient repeatability and that the signal fluctuation across the triplicates emerged as a powerful filtering criteria. The number of false positives and false negatives could be significantly reduced by the developed strategies which consequently improve the validity of the data. The second part of this thesis addresses the development of processing strategies particularly aimed at assessing water treatment processes. The detected signals were tracked across the treatment process and classified based on their fold changes. A more reliable signal classification was achieved by implementing a recursive integration approach. Special integration algorithms allow a reliable signal classification even though the signal to be compared was below the intensity threshold. Different combinations of replicates of process influents and effluents were processed for evaluating the repeatability. The good repeatability was indicated by the results of both the plausibility checks and the ozonation process (ozonation of pretreated river water) and thus points to high reliability. The developed procedure enables the assessment of water treatment processes based on the changes in the pattern of all detected signals and offers a more comprehensive picture of the treatment efficiency. Particularly with regard to transformation products, existing knowledge gaps can be reduced by this approach, albeit the entire variety of chemicals cannot be covered completely. The applicability of the developed strategies to real world applications is demonstrated in the last part of this work. Besides the prioritization of the generated results, the main focus was the identification of recognized compounds. The developed strategies clearly improve the validity of the underlying data. The combination of LC-HRMS analysis with reliable processing strategies opens up multiple possibilities for a more comprehensive monitoring of water resources and for the assessment of water treatment processes. The processing strategies and validation concepts may be easily transferred to other research fields.
In this cumulative thesis, I present four manuscripts and two appendixes. In the manuscripts I discuss mindsets and their relation to the effectiveness of negotiation training. My general claim is that mindsets promise to be relevant for training effectiveness. Still, more research needs to be done and my co-authors of chapter 3 and I present the Scale for the Integrative Mindset of Negotiators (SIM) that can be used for some of that research. In the appendixes, I present two negotiation training exercises. The first addresses an international refugee policy summit and the second a negotiation over the sale of a large solar pv park in Thailand.
Machinima sind aus einer partizipatorischen Medienkultur der Zweckentfremdung, Aneignung und Adaption von Medientechnologie hervorgegangen und haben sich als ein maßgeblicher ökonomischer, sozialer und kultureller Faktor der Unterhaltungsindustrie etabliert. Das Ziel der vorliegenden Doktorarbeit besteht darin, die emergente Entstehung von Quake Movies und deren Stabilisierung als Machinima, d. h. als Akteur-Netzwerke menschlicher und nichtmenschlicher Akteure zu beschreiben, die Intermedialität des Mediums über Bildanalysen zu identifizieren und Akteur-Netzwerke und mediale Formen in einen Zusammenhang mit medialer Ästhetik zu setzen. Die Gesamtentwicklung reflektierend, werden diese Zusammenhänge wiederholt analysiert und gemäß der unterschiedlichen Entwicklungsphasen der Invention, Innovation und Diffusion interpretiert. Das Ergebnis dieser Analysemethode ist die Konstruktion eines Entwicklungsnarrativs, das am Werk empirisch nachvollziehbar ist und bis dato eine Forschungslücke bzgl. der Erschließung der Geschichte und Theorie von Machinima schließt. Es werden des Weiteren Kernfragen der Medien und Bildgeschichte, der Medientheorie sowie der Technikforschung und Innovationsforschung behandelt.
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 so far underexplored in sustainability transitions scholarship 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.
Seit den frühen 1990er Jahren wird transdisziplinäre Nachhaltigkeitsforschung in Form von problemorientierten Forschungs- und Lernprojekten konzeptioniert und praktisch umgesetzt, an denen außeruniversitäre Akteur_innen beteiligt sind. Diese Forschungsarbeit verfolgt drei Ziele: Erstens, die Konzeptualisierung der Begriffe Kultur, Multi-, Inter- und Transkulturalität in der Literatur zur transdisziplinären Nachhaltigkeitsforschung zu untersuchen. Zweitens, die Konzeptionierung und Umsetzung von transdisziplinären Forschungs- und Lernprojekten in Hinblick auf kulturelles Differenzieren zu analysieren. Drittens, konzeptionelle Beiträge zur Gestaltung von transdisziplinären Forschungs- und Lernprojekten zu entwickeln. Methodisch wird auf Literaturanalysen und eine qualitative Untersuchung zweier transdisziplinärer Lernforschungsprojekte zurückgegriffen. Unter dem Begriff Forschungs- und Lernprojekt werden in dieser Forschungsarbeit sowohl Forschungsprojekte als auch Lehr-Lernforschungsprojekte gefasst. Zentrale Ergebnisse der Forschungsarbeit sind die Folgenden: Erstens wird der Kulturbegriff in der transdisziplinären Nachhaltigkeitsforschung zwar vielfältig verwendet, als Forschungsthema, Hintergrund von Beteiligten, Kooperationsweise, Projektkontext, in Hinblick auf Interkulturalität oder als Wissenskultur, allerdings kaum ausdifferenziert und konkretisiert. Zweitens besteht auf der Ebene der Konzeptionierung von transdisziplinären Forschungs- und Lernprojekten: 1) ein starkes Übergewicht von Integration und Konsens gegenüber einer Auseinandersetzung mit Differenz, 2) eine implizite Vorauswahl von Beteiligten durch bestimmte Begrifflichkeiten und methodologische Ansätze und 3) eine Reproduktion von Machtverhältnissen durch (dichotome) Symmetrie- und Ausgleichsvorstellungen. Drittens zeigt sich auf der Ebene der Umsetzung von Lernforschungsprojekten: 1) eine starke Prozessorientierung der Projekte, 2) ein Spannungsfeld zwischen einer Öffnung und Steuerung in Hinblick auf den Projektverlauf und 3) vielfältige Differenzaushandlungen in Interaktionen (wie Zeitlichkeit, Verantwortung, Erfahrung, Relevanz). Die Ergebnisse zeigen, dass politische Implikationen der Forschung und zentrale Ungleichheitskategorien der Kultur- und Sozialwissenschaften (u.a. race, class, gender, body) kaum thematisiert werden. Vorschläge zur Gestaltung transdisziplinärer Forschungs- und Lernprojekte werden in Hinblick auf ein Verständnis von Forschungsdesigns als Prozesse, einem Erkunden von Differenzierungen und Forscher_innen-Positionen und der Bedeutung eines Verlernens entwickelt. Die folgenden Vorschläge zur Gestaltung von transdisziplinären Forschungs- und Lernprojekten werden aus den Ergebnissen entwickelt: Kulturkonzepte sollten nicht als voneinander getrennt, sondern als miteinander verschränkt betrachtet werden. Generell sollten Kulturkonzepte stärker definiert werden. So können durch offene Kulturkonzepte problematische Implikationen (Stereotypen, Rassismus, Kulturalisierung) vorgebeugt werden, die Zielen transdisziplinärer Forschung entgegenstehen. In Hinblick auf die Arten und Weisen kulturellen Differenzierens sollte bewusster mit Differenzierungen umgegangen werden (Wer differenziert wen wie?). Dies schließt ein, eine Sensibilität gegenüber kulturellem Differenzieren zu entwickeln und Differenzierungen in Forschungsprozessen zu erkunden. Kulturelles Differenzieren entfaltet ein wichtiges epistemologisches und transformatives Potential in der transdisziplinären Forschung, um Selbstverständlichkeiten zu reflektieren und Gemeinsamkeiten zu entdecken.
Die Arbeit thematisiert den in der Frühen Bildung spezifischen Bereich des Leitens der Institution Kindertageseinrichtung´. Im Zentrum steht eine an Erkenntnissen der Führungsforschung und Educational Governance Forschung mehrebenenorientierte qualitative Studie zu den Kontexten bzw. Einflüssen auf Leiten. Durchgeführt werden mit insgesamt 35 Teilnehmerinnen und Teilnehmern aus dem System Kindertageseinrichtung fünf problemzentrierte Expertinnen- und Experteninterviews, sowie begleitend Mappingverfahren. Die Auswertung wird als zusammenfassende und inhaltlich-strukturierende qualitative Inhaltsanalyse realisiert. Es wird herausgearbeitet, dass das Leiten von Kindertageseinrichtungen eingebettet ist in ein komplexes und kontingentes Gefüge verschiedener Kontextfelder, die das Leiten mit gestalten. In den Ergebnissen spiegeln sich u.a. drei thematische Ergebniscluster wider, mit denen neben den in der Fachdiskussion häufig thematisierten personalen Kontexten, die mit der Person der Kita-Leiterinnen und Kita-Leiter selbst verknüpft sind, und strukturell verankerten Kontexten vielfach sozial-kommunikative Kontexte verschiedener Akteursgruppen im System Kindertageseinrichtung sowie kulturelle Kontexte sichtbar werden, die soziale Interaktionen als aufeinander bezogenes Handeln als bedeutsame Einflüsse auf Leiten beschreiben. Sie verdeutlichen die von den Expertinnen und Experten wahrgenommenen gegenwärtigen Einflüsse auf das Leiten von Kindertageseinrichtungen und zeigen auch für eine positive Zukunft auf, dass neben personalen Einflüssen auf der einen Seite und strukturbezogenen Einflüssen auf der anderen Seite in breitem Umfang der Zusammenarbeit, der Kooperation und Beteiligung im System Kindertageseinrichtung eine wesentliche Funktion zukommt.
The overall aim of this PhD-thesis is to develop empirical probabilistic frameworks that help to quantify the impacts of temporal and spatial scale dependencies and model uncertainties of climate projections regarding precipitation-dependent parameters. The thesis is structured in four journal articles. Article one is the first study that analyzed climate projections from the spatially highly resolved regional climate model (RCM) ensemble EURO-CORDEX. Additionally, the significance and the robustness of the projected changes are analyzed, and improvements related to the higher horizontal resolution of the new data set are discussed. A major finding is, that RCM simulations provide higher daily precipitation intensities, which are missing in the global climate model (GCM) simulations, and that they show a significantly different climate change of daily precipitation intensities with a smoother shift from low towards high intensities. The second article elaborates on impacts of temporal and spatial aggregation on extreme precipitation intensities. By combining radar data with cloud observations, the different temporal and spatial scaling behavior of stratiform and convective type precipitation events can be analyzed for the first time. The separation between convective and stratiform type events also allows to quantify the contribution of convective events to the extremes. Further, it is shown that temporal averaging has similar effects on the precipitation distribution as spatial averaging. Associated pairs of temporal and spatial resolutions that show comparable intensity distributions are identified. Using precipitation data from radar observations, a gauge station network and a spatially highly resolved regional climate model, the third paper optimizes the process that finds associated temporal and spatial scales (see second article). This information is used to develop a method that adjusts point measurements to the temporal and spatial scale of a previously defined model grid. The study shows that this procedure can be used to improve bias-adjustment methods in areas with a low gauge station density. It is known that the EURO-CORDEX ensemble overestimates precipitation and shows a common cold bias in the Alpine region. The fourth article evaluates how these biases are changing the temperature distribution and the temperature dependency of precipitation-frequencies. These biases are a source of uncertainty that is not captured by the robustness tests performed in the first article. A probabilistic-decomposition-framework is developed to quantify the impact of these biases on precipitation-frequency changes and to investigate causes for the ensemble spread.
The concept of empowerment has gained considerable attention in the field of international development. Institutions such as the World Bank and the United Nations invest considerable funds and efforts trying to facilitate empowerment in developing countries. This is because empowerment is seen as a positive phenomenon that can positively impact on people and their environment. Empowerment provides an implemental mindset that makes people look for the means to action and be ready to move forward toward their goals. Thus, empowerment becomes important when people need to take action and be innovative in overcoming scarcity and fighting against poverty. Research shows the positive effects of empowerment on entrepreneurship-related behavior and outcomes such as proactive behavior, goal achievement, and innovation. Yet, there is a dearth of research addressing the phenomenon of empowerment in entrepreneurship. This dissertation aims to contribute to the understanding of the role of empowerment in entrepreneurship and its effects. Particularly, this dissertation targets the interplay between empowerment and entrepreneurship in the context of developing countries. Chapter 1 provides a general overview of the different topics of this dissertation. Chapter 2, introduces the construct of psychological empowerment at work as the theoretical foundation to advocate for the importance of empowerment in entrepreneurship. The chapter takes initial steps in drawing the rationale and identifying empirical evidence for the relationship between empowerment and entrepreneurial behavior and outcomes. Specifically, the chapter links the components of psychological empowerment to concrete action characteristics in entrepreneurship such as effectuation and experimentation. Chapter 3 establishes a first empirical link between empowerment and entrepreneurship. The chapter provides the construct of entrepreneurial empowerment and develops a multidimensional measure to measure its dimensions. By means of a nomological network, the chapter reveals the relations of entrepreneurial empowerment with relevant constructs and outcomes derived from entrepreneurship and empowerment research such as innovation, self-reliance, and decision-making. Chapter 4 posits entrepreneurship training, particularly personal initiative training and business literacy training, as effective means to facilitate entrepreneurial empowerment and its effect on business performance. The chapter uncovers the mechanisms accounting for the relationship between entrepreneurship training and entrepreneurial empowerment. Chapter 5 provides general theoretical and practical contributions and finishes with a general conclusion. This dissertation contributes to the understanding of empowerment in entrepreneurship and its effects on business performance in the context of developing countries. The studies embedded in this dissertation can serve to further the development of theory and research that advances groundwork of empowerment in entrepreneurship. The construct of entrepreneurial empowerment can stimulate the use of more accurate indicators when conceptualizing and investigating the process and consequences of empowerment in entrepreneurship and international development.