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In the discourse on pharmaceuticals in the environment, hardly any attention has been paid to anticancer drugs. Because of their none-selective modes of action, that is, because they affect both cancerous and healthy cells, these drugs are regarded as potentially carcinogenic, genotoxic, mutagenic, and teratogenic substances. It is, however, not known how and to what extent these substances affect organisms and the environment in the long run. For this reason, this dissertation evaluated, addressing several endpoints and using organisms from different trophic levels and in silico predictions, the fate (bio- and photo degradation) and ecotoxicity of these substances. Four anticancer drugs (cyclophosphamide (CP), 5-fluorouracil (5-FU), methotrexate (MTX), and imatinib (IM) were selected. None of these anticancer compounds can be classified as ´readily biodegradable,´ a classification that indicates that biodegradation will only play a minor role in the elimination of these compounds and that they cannot be removed by the conventional processes used in sewage treatment plants and will most likely remain in the water cycle. Despite the high degrees of mineralization achieved in advanced (photo)oxidation processes, it was not possible to fully mineralize the compounds, a result that indicates that transformation products were created during these reactions. The ecotoxicity assays performed with V. fischeri indicated that 5-FU was, of all the substances tested, likely to be the most toxic (very toxic), followed by MTX (toxic) and IM (toxic/harmful), whereas CP was nontoxic. MTX presented the highest phytoxicity activity in the Lactuca sativa assay, followed by 5-FU, IM, and CP. The results of the tests performed with A. cepa showed cytotoxic (5-FU, MTX, and CP) and genotoxic effects (5-FU, CP, and IM) and mutagenic activity (5-FU, MTX, CP, and IM) of the compounds. Photo transformation products (PTPs) of CP, MTX, and 5-FU were nontoxic towards V. fischeri. However, some PTPs formed during the photodegradation of 5-FU led to positive mutagenic and genotoxic alerts in several in silico models. Not one of the compounds examined in this dissertation is likely to be fully eliminated from the water cycle by (natural) photolysis and/or advanced oxidation. Moreover, some of the treatments resulted in the formation of stable intermediates that were even less biodegradable than parent compounds. This finding shows that it is not enough to focus on primary elimination because TPs are not necessarily better biodegradable than their respective parent compounds. As indicated by the genotoxic and mutagenic positive alerts presented by different in silico models, the PTPs observed here are likely to require, despite their lower toxicity in comparison to the parent compounds, screening after treatments.
Traditional farming landscapes have been created in coexistence of rural dwellers and local ecosystems over long time spans, and can be considered tightly coupled ´social-ecological systems´ (SES). Since these landscapes typically embody exceptionally high levels of biological diversity and multiple socio-cultural values, their protection is critical from a sustainability perspective. Due to the pressures of globalization and social change, however, rural livelihoods and farmland biodiversity are at risk. While the focus of research is often on the Southern hemisphere, there are traditional farming landscapes in the former socialist countries of Central and Eastern Europe (CEE) which are equally affected by rapid change, and thus deserve particular attention. Since the institutional breakdown of socialism in 1989, the CEE states have not only been confronted with an unprecedented socio-economic and environmental transition. Their integration into the multi-level governance regime of the European Union (EU) further resulted in the transformation of decision-making structures and competition within the EU common market. In light of the profound changes traditional farming landscapes of Central and Eastern Europe are confronted with, they serve as a valuable source of learning about the institutional design necessary to harmonize socio-economic development and biodiversity conservation within regional social-ecological systems worldwide. This thesis is the result of an in-depth analysis of one traditional farming landscape of Central and Eastern Europe, namely Southern Transylvania (Romania). Based on empirical research involving diverse stakeholder groups, this thesis assessed the impact of EU policy on the area, the institutional features characterizing local-level governance in Southern Transylvania, and the barriers and bridges towards sustainable rural development. This thesis finds that while rural dwellers are highly dependent on smallholder farming and local ecosystems for their livelihoods, Southern Transylvania is currently confronted with a range of structural development barriers. These are likely to be exacerbated by a governance system consisting of historically grounded ´elite social networks´, and by EU policies which often do not fit rural realities. The findings of this dissertation underline that entrenched informal institutions, political will, and historical legacies play a critical role for the governance of traditional social-ecological systems since these ´social system features´ do not only mediate how external policies act on the local level. They may further restrict local adaptive and innovation capacities which, however, are critical for the transformation towards sustainable development. This thesis further finds that there are no blueprint solutions for the design of rural development strategies. Instead, (supra-) national policies should take better account of local socio-economic and cultural particularities.
Entrepreneurship is an important means for economic development and poverty alleviation . Due to the relevance of entrepreneurship, scholars call for research that contributes to the understanding of successful business creation. In order to best understand new venture creation, research needs to investigate barriers of entrepreneurship. A barrier that has received wide attention in the literature on new venture creation is capital requirements. Scholars argue that capital requirements are an entry barrier for new venture creation, as most people who start businesses have difficulties in acquiring the necessary amount of capital needed for starting the businesses. Particularly in developing countries, scholars and practitioners regard improvements in access to capital as a major solution to support new venture creation. However, besides improving access to capital, there are alternative solutions that help to deal with the problems of capital requirements and capital constraints in the process of new venture creation. In this dissertation, I argue that a possible means to master capital requirements and capital constraints in business creation is action-oriented entrepreneurship training. I draw on actionregulation theory (Frese & Zapf, 1994), theories supporting an interactionist approach (Endler & Edwards, 1986; Terborg, 1981) and on theories about career development (Arthur, 1994; Briscoe & Hall, 2006) to reason that action-oriented entrepreneurship training allows for handling capital requirements and capital constraints with regard to business creation. Specifically, I argue that action-oriented entrepreneurship training helps to deal with financial requirements and capital constraints in two ways: First, the training reduces the negative effect of capital constraints on business creation through the development of financial mental models. Second, the training supports finding employment and receiving employment income, which enable businesses creation.
Fire plays an important role in the earth system by influencing ecosystems and climate, but climate in turn also influences fire. The system became more complex when humans started using fire as a tool. Understanding the interaction between humans, fire and climate is the major aim of paleofire research. Understanding changes in these three aspects in the past will help predicting future climate, fire and human interactions. The use of lake sediment cores as natural archives for reconstructing past fire activity by counting charcoal particles is well established. This present dissertation is dedicated to the evaluation and application of specific organic molecular markers for biomass burning: levoglucosan, mannosan and galactosan were used as proxies for reconstructing past fire activity in lake sediments thorough the entire Holocene. First, a new analytical method was developed using high-performance anion exchange chromatography combined with mass spectrometry to separate and detect these three monosaccharide anhydrides in lake sediments. The suitability of this analytical method was proven by comparing the levoglucosan, mannosan and galactosan results in selected lake sediment samples from Lake Kirkpatrick, New Zealand and by correlating the results with macroscopic charcoal. Furthermore, the method was successfully applied to a lake sediment core from Lake Petén Itzá, Guatemala to reconstruct regional Holocene fire history. The analyses of levoglucosan were combined with fecal sterols to reconstruct late Holocene human fire interactions at Lake Trasimeno, Italy, demonstrating low fire activity during the Roman period. This combination of studies proves that these molecular markers are valid fire proxies in sediments from multiple locations around the globe. Comparison of levoglucosan, mannosan and galactosan concentrations with macroscopic charcoal trends in Lake Kirkpatrick and Lake Petén Itzá, suggests that the molecular markers represent more regional fire history and low temperature fires in contrast to macroscopic charcoal, which is a local fire proxy. In addition, vegetation changes (Lake Kirkpatrick and Lake Petén Itzá) and charcoal morphotypes (Lake Petén Itzá) were compared to the levoglucosan/mannosan and levoglucosan/(mannosan+galactosan) ratios suggesting that these ratios may be a suitable tool to track burned fuel. Biodegradation tests demonstrate the potential degradation of levoglucosan, mannosan and galactosan if dissolved in water, but findings in ancient sediment samples suggest that particle-bound levoglucosan, mannosan and galactosan can be buried in sediments over millennial time scales. Although uncertainties still exist, the results of this research suggests that organic molecular markers are a suitable regional fire proxy and isomer ratios may help understand changes in burned vegetation.
The importance of a social perspective on the relationships between humans and nature has longbeen acknowledged. The field of social-ecological systems research in particular is striving toachieve a holistic understanding of human-nature relationships by balancing social andecological perspectives. Here I sought to develop a social understanding of the Saxon area inCentral Romania, by exploring aspects of human-nature relationships as seen from theperspective of local people. To this end, I employed the concepts of social-ecological systems(SES), ecosystem services (ES) and cultural landscapes to assess perceptions of locals throughempirical case studies.I first conducted a literature review to acquire an overview of a particular type of human-naturerelationship mediated by non-consumptive use and non-use values (“cultural ecosystemservices”). Second, to isolate and address the interaction from the social system to the ecologicalsystem, I investigated the different ways locals perceived the role of landscapes in SouthernTransylvania. I conceptually mapped these landscape preferences by revealing their potentialland use and management implications. Third, to approach the human-nature relationship fromthe ecological system to the social system, I studied the flow of ES to disaggregated humanbeneficiaries. Specifically, I studied which factors, beyond ecosystem processes and functions,influenced nature derived human well-being from the perspective of potential beneficiaries. Iconceptualised the mediating role of a range of contextual factors underpinning the currentdistribution of ES, with regard to the relation between ES and human well-being. Fourth, inorder to explore an example of bidirectional human-nature relationship, I studied the particularcase of human-carnivore coexistence and the suite of mechanisms shaping it.Despite building throughout this thesis a more complex and in-depth understanding of the humandimensions of the studied system, I chose four main cross-cutting themes to explain the human-nature connection in Southern Transylvania. These four themes may serve as pillars of a sociallyminded understanding, as well as potential research and policy foci. First, the values held bylocals are key for understanding the endemic human-nature relationships and should not beoverlooked in future social-ecological assessments or policy interventions. Second, the culturallandscape of Southern Transylvania is both a physical and virtual space of social-ecologicalinteraction fostering human-nature experiences and social-ecological knowledge integration.Third, the identified diversity of the social system in terms of landscape aspirations and ESbeneficiaries is expanding the range of human-nature connections, but at the same time, may infuture be a source of conflict or disconnection if not managed appropriately. Finally, small-scalefarmers, through their interactions with the land and resultant belief system, play a major role inmaintaining the human-nature relationships, but their values and lifestyle are threatened.
This dissertation deals with the investigation of success factors in the field of entrepreneurship, especially entrepreneurship training, from a psychological perspective. In particular, I argue that the identification of certain psychological aspects helps to better understand the underlying mechanisms for successful entrepreneurship trainings and thus, enables successful entrepreneurship. In the second chapter I theoretically examined planning as a fundamental action an entrepreneur hast to undertake in order to succeed. Scholars are in disagreement about the question if planning is crucial for the entrepreneurship. Thus, I provide a comprehensive overview of the advantages and disadvantages of planning in entrepreneurship from a psychological perspective. I explain negative aspects (e.g., lack of knowledge, difficulty to predict the future, and inflexibility) as well as positive aspects (e.g., legitimating, action-regulatory, and learning function) about planning in entrepreneurship. Furthermore, I develop a theoretical model that combines both the positive and negative aspects of planning in entrepreneurship. With this theoretical model, I integrate different types of planning (e.g., formal and informal plans) as well as positive and negative functions of planning (e.g., learning or stickiness, inflexibility) to provide a first approximation for a theory of entrepreneurial planning. In the third chapter, to focus on the field of entrepreneurial trainings, I empirically examine the under-researched field of the relation between trainer and trainee. I use the transformational leadership theory (Bass, 1985) and a theory of learning outcome (Kraiger, Ford, & Salas, 1993), to hypothesize that the trainers´ charisma has a positive effect on the trainees´ entrepreneurial self-efficacy. Additionally, I search for possible moderators for the hypothesized trainer-trainee-relationship in an explorative manner, using insight from different research areas (e.g., pedagogy, philosophy). To test the hypotheses, I conducted a 12-week entrepreneurship training by which I had 12 measurement waves across four classes with 161 students and 12 trainers, which lead to 919 observations. In the fourth chapter, to broaden the perspective on the mechanisms within entrepreneurship training, which lead to a successful outcome, I empirically examined the short- and long-term effects of entrepreneurship training on life satisfaction. To do so, I developed a theoretical model based on theories of life satisfaction, that explain the underlying mechanisms of the short- and long-term effects of the entrepreneurship training on life satisfaction. With this model I hypothesize, that entrepreneurship training has a positive short- effect on life satisfaction, which is mediated through entrepreneurial self-efficacy. I furthermore hypothesize, that the long-term effect of the entrepreneurship training is mediated through self-employment. The short term-effect acts like a boost and vanishes over time, whereas the long-term effect holds in the long run. To test these hypotheses, I conducted entrepreneurship training as part of a randomized controlled field experiment with five measurement waves over a total period of 2.5 years. Using discontinuous growth modeling to take into account the temporality of our hypothesized effects we statistically analyzed the 1,092 observations from 312 students. Chapter 5 concludes this dissertation with general discussion of the three chapters.
Traditional farming landscapes typically support exceptional biodiversity. They evolved as tightly coupled social-ecological systems, in which traditional human land-use shaped highly heterogeneous landscapes. However, these landscapes are under severe threats of land-use change which potentially pose direct threats to biodiversity, in particular through land-use intensification and land abandonment. Navigating biodiversity conservation in such changing landscapes requires a thorough understanding of the drivers that maintain the social-ecological system. This dissertation aimed to identify system properties that facilitate biodiversity conservation in traditional farming landscape, focusing specifically on birds and large carnivores in the rapidly changing traditional farmland region of Southern Transylvania, Romania. In order to identify these properties, I first examined the effects of local and landscape scale land-use patterns on birds and large carnivores and how they may be affected by future land-use change (Chapters II-V). Second, to gauge the role of particular traditional land-use elements for biodiversity I focused on the conservation value of traditional wood pastures (Chapters VI-VIII). Third, I took a social-ecological systems approach to understand how links between the social and ecological parts of the system affect human-bear coexistence (Chapters IV and IX). Bird diversity was supported by the broad gradients of woody vegetation cover and compositional heterogeneity. Land-use intensification, and hence the loss of woody vegetation cover and homogenization of land covers, would thus negatively affect biodiversity. This was especially evident from predictions on the distribution of the corncrake (Crex crex) in response to potential future land cover homogenization. Here, a moderate reduction of land cover diversity could drastically reduce the extent of corncrake habitat. Further results showed that the brown bear (Ursus arctos) would mainly be affected by land-use change through the fragmentation of large forest blocks, especially if land-use change would reduce habitat connectivity to the presumed source population in the Carpathian Mountains. Moreover, this dissertation revealed that large carnivores (brown bear and wolf, Canis lupus) may have important and often ignored roles in structuring the ecosystem of traditional farming landscapes by limiting herbivores. Wood pastures were found to have a high conservation value. The combination of low-intensity used grasslands with old scattered trees provided important supplementary habitat for different forest species such as woodpeckers and the brown bear. Worryingly, current management of wood pastures differed from traditional techniques in several aspects, which may threaten their persistence in the landscape. The majority of people had a positive perception on human-bear coexistence. The use of traditional sheep herding techniques combined with the tolerance of some shepherds to occasional livestock predation facilitated coexistence in a region where both carnivores and livestock are present. More generally, the genuine links between people and their environment were important drivers of people´s positive views on coexistence. However, perceived failures of top-down managing institutions could potentially erode these links and reduce people´s tolerance towards bears. Through the consideration of two different animal taxa, this dissertation revealed six important system properties facilitating biodiversity conservation in traditional farming landscapes. Similar proportions of the main land-use types (arable land, grassland, and forests) support species richness at the regional scale possible through habitat connectivity and continuous spill-over between land-use types. Heterogeneous landscapes can further support biodiversity through complementation and supplementation of habitat at the landscape scale. Gradients of woody vegetation cover and heterogeneity, supported biodiversity at both local and landscape scales possibly through the provision of a wide range of resources. The heterogeneous character of the landscape is tightly linked to traditional land-use practices, which also maintain specific traditional land-use elements and facilitate human-carnivore coexistence. Top-down limitation of large carnivores on herbivores possibly enhances vegetation growth and tree regeneration. The genuine links between humans and nature support human-bear coexistence, and these links may form the core of people´s values and sustainable use of natural resources.
This PhD thesis examines the connections between sustainability knowledge management (SKM) and sustainability management tools in small and medium-sized enterprises (SMEs). While previous literature has established that knowledge is essential for the application of sustainability management tools, the effects of such tools on knowledge management are under-researched in the sustainability context. Drawing on multiple academic papers and utilizing various research methods, including a systematic literature review, several quantitative surveys and a multiple case study approach, the thesis systematically examines how such tools can facilitate the identification, acquisition, conversion, application and retention of sustainability knowledge, and potentially lead to the improvement of SKM effectiveness in SMEs. Furthermore, it examines how support functions for sustainability management tools and SKM correspond with each other. The findings reveal that sustainability management tools facilitate the SKM processes (identification, acquisition, conversion, application and retention), and align with the support factors (e.g. top management support, shared vision, employee qualifications) to advance SKM in SMEs. Particularly, such tools permit the institutionalization of sustainability knowledge into the daily routines and practices in SMEs. Additionally, tools create a support structure for SKM, embedding and preserving sustainability knowledge in documents, policies, procedures and norms for an enterprise´s collective knowledge for sustainability management. The thesis concludes with complementing areas of future research and offers practical implications for SME management.
A characteristic of the German health care market is the high complexity, amongst others due to the plurality of actors and interest groups. With so many players involved, health care reforms necessarily are the outcome of a quest for influence reflecting the relative power of interest groups. However, in much of the health economics literature, this fact is neglected, with the consequence that public regulation fails to have the intended effect. The treatment of social (interest) groups is central to understand political economic processes. Basic models in this area are the models of Olson (1965), Peltzman (1976) and Becker (1983). The objective of such model considerations in the health care market is to maximize efficiency and quality of care and thereby reduce expenditures. The section “The German health care market and its players: An overview from an economic perspective” analyses the structure of the health care market in Germany together with selected health challenges of the last decade. It questions to which extent the new political economy in contrast to welfare economy is able to explain health economic aspects. The section “Drug Prices and Pressure Group Activities in the German Health Care Market: An Application of the Becker Model” analyses the shift of power and influence among the pharmaceutical industry, the pharmacies and the social health insurers (SHI). Since the health care reform in 2004, these interest groups have been negotiating the structure of surcharges and discounts among each other without any intervention from the government. This reflects the assumption of a passive government in the Becker (1983) model and makes this model to a good choice for application. The negotiations and the resulting amendments of this ordinance express the shift of power and influence among the involved interest groups in the German health care market after 2004. The first assumption is a closed system based on the theoretical work by Becker. The amount of total budget and the amount of total influence is constant and defined as 10. In such a standardized system, the influence by producers and pharmacies decreases about 0.007 units of political pressure to the value 9.989, whereas the influence by SHI increases about 0.007 units to the value 0.011 between 2008 and 2010. More realistic is the second assumption, the assumption of an open system where the amount of total budget and the amount of total influence can change over the years. With this assumption a trend becomes apparent which shows an increase in political pressure by SHI about 0.015 units to the value 0.036 and a decrease of political pressure by pharmacies and producers about 18.326 units to the value 34.022 between 2008 and 2010. This reflects the cost control trend in combination with the empowerment incentives for SHI. Noteworthy is the high pressure level of producers compared to the other interest groups. As a conclusion one can say that the last years show a movement to more competition between the interest groups. This leads to more balanced power relations. But nevertheless, the most powerful group is still the producer group and the influence of the SHI is still very low. However, the government does not always behave passively. On sensitive issues for voters such as co-payments, the government tries to maximize votes. So, in the section “Drug Prices, Rents, and Votes in the German Health Care Market: An Application of the Peltzman Model”, the reaction of consumers (insured persons) and producers (pharmaceutical industry) based on electoral behavior and relating to drug prices and co-payments imposed on drugs is analyzed, using the health care reform of 2004 as an experience. The changes in prices and medications after this reform make it to a natural choice. For the analysis, the interest group model by Peltzman (1976) is applied to the German health care market. The vote-maximizing government has to find the optimal combination of rent and price of regulation. For the optimum solution, the variation of votes on the part of pharmaceutical industry has to equal the variation of votes on the part of consumers. Reflecting different power structures leads to drug prices ranging from 5 to 50 Euros, associated with a co-payment of 5 Euros. Prices between 50 and 100 Euros are possible as well, reflecting a balance of power facing the pharmaceutical industry. These prices are associated with a co-payment of 10% of the selling price. Concerning the transition from 1989 reference price regime to the 2004 reform one can say that producers who had accepted the reference price had an incentive to increase their price while lowering their sales volume.