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Perfluoroalkyl and polyfluoroalkyl substances (PFASs) have been widely used since 1950 in various consumer products as well as in industrial applications owing to their unique properties, e.g. being hydrophobic and lipophobic at the same time. Nowadays, some of these persistent and man-made PFASs can ubiquitously be found in humans, wildlife and various environmental media. One prominent representative of concern, belonging to the subgroup of perfluorocarboxylates (PFCs) and their conjugate acids (PFCAs), is perfluorooctanoat (PFO) and its conjugate acid (PFOA). Because of its adverse effects on human health and its persistency in the environment industry has started to replace PFO(A) and related long chain chemicals (with seven and more fully fluorinated carbon atoms) with so-called short chain PFASs (less than seven fully fluorinated carbon atoms), including precursors of PFC(A)s. Also these short chain PFC(A)s are persistent and can already be found in humans, ground- and drinking water and in remote regions. However, knowledge gaps exist in understanding the partitioning and the resulting mobility of short chain PFC(A)s in the environment. This is due to the fact that partitioning data of PFC(A)s from standardised experiments can easily be biased by various artefacts, e.g. self-aggregation of the molecules. Therefore, the objectives of this thesis are (i) to quantify the partitioning of PFC(A)s into mobile environmental media, (ii) to show how results from non-standard tests can be used to assess substance properties of concern and (iii) to conclude on whether the environmental exposure to short chain PFC(A)s is of concern from a regulatory point of view. In the first part of this thesis, the environmental mobility of short chain C4-7-PFC(A)s was investigated by quantifying their partitioning under non-standardised semi-environmental conditions into mobile environmental media, focusing on water and air, and comparing it to long chain PFC(A)s. Results are: Partitioning between water and particles in the aeration tank, primary and secondary clarifier of a wastewater treatment plant (WWTP) showed no distinct differences for short chain PFC(A)s compared to their long chain homologues (Paper 1). In a water-saturated sandy sediment column short chain PFC(A)s were not retarded, whereas long chain homologues were retarded by sorption to the sediment (Paper 2). Atmospheric particle-gas partitioning showed a lower fraction sorbed to particles for short chain PFC(A)s compared to long chain ones in samples from a WWTP (Paper 3). Air-water concentration ratios based on samples from the tanks of a WWTP were found to be higher for short chain PFC(A)s compared to long chain PFC(A)s (Paper 1). Additionally, in a newly developed experimental set-up the water to air transfer was used to derive that the pKa of C4-11-PFCAs must be <1.6 instead of up to 3.8 as reported in the literature (Paper 4). Overall, in the investigated systems short chain PFC(A)s showed a higher mobility due to a more pronounced partitioning into mobile environmental media compared to long chain PFC(A)s. In the second part of the thesis it was shown how PFO(A) - owing to its persistent, bioaccumulative and toxic (PBT-)properties – was in the context of this thesis successfully assessed as a substance of very high concern according to the criteria of the European REACH Regulation (EC No 1907/2006) by using data from non-standard tests (Paper 5). In conclusion, based on the knowledge of the high environmental mobility of short chain PFC(A)s and taking into account the argumentation of the PBT-concern of PFO(A), environmental exposure to short chain PFC(A)s is of concern and existing knowledge is already sufficient to initiate measures to prevent emissions of short chain PFC(A)s and their precursors into the environment.
The fact that digitalization comes along with a lot of negative effects onto the environment is slightly known in the case of energy consumption by hardware, especially regarding mobile devices, having a limited battery life. However, awareness of environmental issues of software, being the driver of hardware, is mainly missing, even if the research field addressing corresponding issues is growing. Thus, the doctoral thesis at hand addresses the question How to draw (a) developers and (b) usersattention to environmental issues of software? By presenting (a) a calculation method of the carbon footprint of software projects and (b) a concept for an eco-label for software products, evaluated by a user survey, the doctoral thesis provides two strategies how to draw the attention to environmental issues of software. Summarizing, this thesis can act as a basis for further research in bridging from science to society in the context of environmental issues of software. Its findings can be seen as starting points for practical implementations of methods and tools supporting a more environmentally friendly way of developing software and informing about environmental issues of software usage. In order to get the implementation of the research results of the thesis going, it highlights practical implications for diverse groups of stakeholders - researchers, certifiers, public administration and professional purchasers, and environmental associations - that have been identified as being important for the practical implementation of the presented concepts and, thus, represent the target group of the doctoral thesis.
Environmental governance beyond borders: Governing telecoupled systems towards sustainability
(2023)
This doctoral dissertation analyses the environmental governance of long-distance social-ecological interactions in telecoupled systems in two issue domains: global commodity chains and infrastructure projects as part of China’s Belt and Road Initiative (BRI). Although both domains involve different governance actors, institutions and processes, they both concern the question of how the involved actors develop governance structures and institutional responses to telecoupling. This dissertation aims to contribute to a deeper understanding of how to govern environmental problems that are associated with global flows. Since many multilateral environmental governance initiatives have not yet produced the desired solutions to global problems, particular attention is directed at unilateral state-led governance approaches. This dissertation addresses the questions of (1) how to achieve a spatial fit between the scale of telecoupled systems and the scale of governance institutions, (2) how governance actors exercise agency in governing telecoupled systems, and (3) how state actors can govern the domestic and foreign environmental effects of telecoupled flows. The results show that creating a spatial fit in the governance of global commodity flows is challenging because boundary and resolution mismatches can emerge. Boundary mismatches denote situations where social-ecological problems transcend established jurisdictional boundaries, whereas resolution mismatches refer to governance institutions that have too coarse a spatial resolution to allow them to address the specific aspects of social-ecological problems effectively. No single governance institution is likely to avoid all mismatches, which highlights the need to align multiple governance approaches to effectively govern telecoupled systems.
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.
This study aims to answer four main research questions regarding the roles, strategies, barriers, and representation of the media and environmental nongovernmental organisations (ENGOs) in environmental communication in Malaysia. From a theoretical lens, this study has incorporated the essential concepts of media, ENGOs, and environmental communication from both Western and Asian, particularly Malaysian perspectives as primary points of reference. For the purpose of this study, a total of 13 interviewees from Media A and Media B and 11 interviewees from ENGO A and ENGO B were chosen for the qualitative interview while 2,050 environmental articles were collected as samples from Media A´s and Media B´s newspapers along with ENGO A´s and ENGO B´s newsletters from the period 2012 to 2014 for the quantitative content analysis. Specifically, the findings from interview confirmed that both the Malaysian media and ENGOs have shared quite similar roles in environmental communication, particularly in environmental legitimacy (creating trust, credibility, and relationships with the public), in democracy (acting as a watchdog and mobilising the public sphere), and in constructing public mind about environmental problems. Pictures undoubtedly were one of the most vital tools in social construction, especially for presenting the reality of the environmental problems to the public. This was in harmony with the results of the quantitative content analysis, where more than 60% of pictures were found on environmental articles in media newspapers and ENGOs newsletters. Malaysian media and ENGOs have shared two common strategies in environmental communication, namely campaigning and collaboration with other stakeholders, while the ENGOs have two extra strategies: advocacy and lobbying strategies. Malaysian media and ENGOs also have collaborated with each other and the level of collaboration between them was at the coordination (medium) level. Both social actors especially the media were also relied heavily on their sources for environmental articles and the result of quantitative content analysis showed that the government was the main source for media newspapers, whereas other ENGOs and laypersons were the main sources for ENGOs´ newsletters. There are also colossal barriers faced by both Malaysian media and ENGOs throughout the process of environmental communication and some of the barriers faced by both media and ENGOs include the problem with limited knowledge of the environment, while some other barriers, like media laws and ownership, were only faced by the media; other barriers such as funding problems were specifically faced by the ENGOs. In terms of representation of environmental information, the Malaysian media make more presentations on environmental problems, especially on topics like floods, wildlife and water crises in their newspapers, while ENGOs have given more attention to environmental effort topics such as conservation and sustainable living in their newsletters. Surprisingly, not only the media but also the ENGOs used the same (news) values like timeliness, proximity, and impact as criteria for the selection of environmental issues for their publications. Other factors such as the background of the organisation and the interest of journalists or editors also influence the selection of environmental issues. It is hoped that the proposed theoretical framework of this study can serve as a crucial guideline for the development of environmental communication studies, especially among the media and ENGOs not only in Malaysia but also in other (Southeast) Asian regions that share a similar background.
Using panel data from Spain Farinas and Ruano (IJIO 2005) test three hypotheses from a model by Hopenhayn (Econometrica 1992): (H1) Firms that exit in year t were in t-1 less productive than firms that continue to produce in t. (H2) Firms that enter in year t are less productive than incumbent firms in year t. (H3) Surviving firms from an entry cohort were more productive than non-surviving firms from this cohort in the start year. Results for Spain support all three hypotheses. This paper replicates the study using a unique newly available panel data sets for all manufacturing plants from Germany (1995 – 2002). Again, all three hypotheses are supported empirically.
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.
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.
Entrepreneurs and Freelancers: Are They Time and Income Multidimensional Poor? - The German Case
(2016)
Entrepreneurs and freelancers, the self-employed, commonly are characterized as not only to be relatively rich in income but also as to be rich in time because of their time-sovereignty in principle. Our introducing study scrutinises these results and notions about the well-being situation of self-employed persons not only by asking about traditional single income poverty but also by considering time poverty within the framework of a new interdependent multidimensional (IMD) poverty concept. The German Socio-economic panel with satisfaction data serves as the data base for the population wide evaluation of the substitution/compensation between genuine, personal leisure time and income. The available detailed Time Use Surveys of 1991/92 and 2001/2 of the Federal Statistics Office provide the data to quantify the multidimensional poverty in all the IMD poverty regimes. Important result: self-employed with regard to single income poverty, single time poverty and interdependent multidimensional time and income poverty in both years are much more affected by time and income poverty than all other active persons defining the working poor. A significant proportion of non-income-poor but time poor of the active population are not able to compensate their time deficit even by an above poverty income. These people are neglected so far within the poverty and well-being discussion, the discussion about the ´working poor´ and in the discussion about time squeeze and time pressure in general and in particular for the self-employed as entrepreneurs and freelancers.