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Institut
Im Zeitraum der Entstehung der vorliegenden Dissertation wurden über 60 Studien publiziert, die sich explizit mit dem Themenkomplex ´Zukunft der Arbeit´ beschäftigen, implizit aber auch immer Ableitungen für das Personalwesen enthalten. Da die Studien durchweg auf sozialwissenschaftlichen Methoden aufbauen bilden sie eine der wenigen direkten Schnittstellen zwischen wissenschaftlicher Theorie und Unternehmenspraxis. In allen diesen Studien finden sich als zentrale Aspekte die Herausforderung zunehmender Komplexität und die damit einhergehende Unsicherheit in strategischen Fragen. Daraus ergibt sich der Impuls für das Forschungsinteresse: Welchen Beitrag kann wissenschaftliche Theorie in der Praxis leisten und welche Transformationen sind notwendig, um die Potenziale der Theorie in der Praxis zu verankern? Bei der Konsolidierung der Praxisstudien mit wissenschaftlichen Ansätzen wird deutlich, dass häufig benutzte Begriffe wie ´Komplexität´, ´System´ oder ´Flexibilität´ als Bestandteile von Erklärungen dienen, kaum jedoch in ihrer wissenschaftstheoretischen Differenziertheit zur Kenntnis genommen werden. Um eine Basis für die Modellbildung zu erarbeiten werden die jeweils zugrunde liegenden theoretischen Modelle detailliert untersucht. Im Laufe dieser Analyse rücken zwei Aspekte in den Mittelpunkt der Untersuchung: Zum ersten das Konzept der Kompetenz im Umgang mit Komplexität als Ausdruck der Handlungsfähigkeit sowohl des Mitarbeiters (Subjekt) als auch der Organisation (System); zum zweiten als Scharnier zwischen diesen beiden Ebenen die Instanz eines entsprechend strukturierten Personalwesens als mögliches umsetzendes Organ. Ausgehend davon werden in der Dissertation konkrete Vorschläge für die Ausgestaltung der zukünftigen Rolle des Personalwesens gemacht und ein Instrument entwickelt, das individuelle Kompetenz als Schlüssel zum Komplexitätsmanagement im Unternehmen berücksichtigt, um maximale Flexibilität im Umgang mit unerwartet auftretenden Ereignissen aufzubauen.
This thesis makes an important contribution to better understanding biodiversity and ecosystem function relationships across trophic levels in forests - aspects that are still underrepresented in BEF research. Ongoing biodiversity loss can be expected to change important trophic interaction pathways in these ecosystems, making increased efforts in exploring the mechanisms underlying, and the drivers determining, the impact of trophic complexity on the relationships between biodiversity and ecosystem functioning a crucial objective for holistic approaches to BEF research.
Recent studies have confirmed that the aquatic ecosystem is being polluted with an unknown cocktail of pharmaceuticals, their metabolites and/or their transformation products (TPs). Although individual pharmaceuticals are typically present at low concentrations, their continuous input into the aquatic ecosystem and their toxic and persistent presence are the major environmental concerns. Therefore, it is necessary to assess the environmental risk caused by these aquatic pollutants. Data on exposure are required for quantitative risk assessment of parent compounds and their transformation products (TPs) and/or metabolites. Such data are mostly missing, especially for TPs, because of the non-availability of TPs and very often metabolites for experimental testing. Therefore, the application of different in silico tools for qualitative risk assessment can be used. Also, the presence of these micro-pollutants (active pharmaceutical ingredients, APIs) in the aquatic cycle are increasingly seen as a challenge to the sustainable management of water resources worldwide due to ineffective effluent treatment and other measures for their input prevention. Given the poor prognosis for effluent treatment (‘end of the pipe’ approach) for input prevention of APIs in the environment, it is necessary to focus on the ‘beginning of the pipe’ strategy. The very beginning of the pipe is the molecules themselves. Therefore, novel approaches are needed like designing greener pharmaceuticals, i.e. better biodegradable ones in the aquatic environment after their release. Therefore, the present research work focused on two important topics a) assessment of the environmental risk associated with the presence of highly prescribed drugs and their TPs; b) demonstrating the feasibility of the ‘benign by design’ concept for designing biodegradable drug derivatives, which will have the better biodegradability in the environment after their release. The present thesis includes four research articles (1-4) which address these approaches. The first article is about the qualitative environmental risk assessment using the example of transformation products formed during photolysis (photo-TPs) of Diatrizoic acid (DIAT). Photolysis is the chemical reaction in which the compound is broken down by photons and often in combination with hydroxyl radicals. Photolysis is the most common abatement process of micro-pollutants in the environment. The qualitative risk assessment of DIAT and selected photo-TPs was performed by the PBT approach (i.e. Persistence, Bioaccumulation and Toxicity), using chemical analysis, experimental biodegradation test assays, QSAR models with several different toxicological endpoints and in silico read-across approaches. The second article addresses a tiered approach of implementing green and sustainable chemistry principles for theoretically designing better biodegradable and pharmacologically potent pharmaceuticals derivatives. Photodegradation process coupled with LC-MSn analysis, biodegradability testing and in silico tools such as quantitative structure-activity relationships (QSAR) analysis and molecular docking proved to be a very significant approach for the preliminary stages of designing chemical structures that would fit into the ´benign by design´ concept in the direction of green and sustainable pharmacy. Metoprolol (MTL) was used as an example. The third article was also the conceptual framework to get new drug derivatives that are biodegradable in order to tackle the global challenge of micro-pollutants in the aquatic cycle. This study increased the knowledge about the role of the attachment of certain functionalities to the parent drug molecule for its biodegradability whilst conserving drug-likeness. This approach was in the past a totally neglected issue within drug development. Atenolol (ATL), a selective β1 blocker, was selected as an example to incorporate the additional attribute such as biodegradability into its molecular structure while conserving its substructures responsible for β adrenergic receptor blocker activity. In fourth article, the concept of designing green biodegradable pharmaceuticals has been proven through expanded experimental analysis setting out from the experiences collected as described in article two and three. This study could be considered as a more extensive feasibility study of rational design of green drug derivatives. The non-selective β-blocker Propranolol (PPL) was used as an example. The risk assessment study (Article #1) contributes in enhancing the existing knowledge about the life cycle and behavior (fate) of pharmaceuticals with a special focus on photo-TPs which are generally formed during advanced effluent treatment and enter as such into the environment. Based on the obtained results, the application of the in silico tools for qualitative risk assessment analysis increased knowledge space about the environmental fate of TPs in case of their non-availability for experimental testing. The benign by design studies (Article #2-4) were based on the knowledge and experience collected during the work on DIAT. It demonstrated the feasibility of a novel approach of designing comparatively better degradable and pharmacological potent derivatives through the implementation of ´green chemistry´ principles. However, the present approach is in the juvenile stage and further knowledge has to be collected beforehand for the full implementation of this approach into drug development.
This paper-based dissertation deals with the concepts of economic heterogeneity and environmental uncertainty from different perspectives, and at multiple levels of abstraction. At its core sits the observation that heterogeneity and uncertainty are deeply entangled, for there would be no uncertainty without heterogeneity of options to act regarding multiple future states of the world. At the same time, heterogeneity - in the form of diversification - has been suggested as a way to reduce uncertainty in portfolio theory (Markowitz 1952). The dissertation evolves around two research foci: (1) methodological implications of heterogeneity of scientific theories in the face of empirical data (Paper 1), and (2) two different forms of uncertainty are considered, environmental risk (Paper 2) and Knightian uncertainty (Paper 3). Paper 1 develops a new framework for model selection for the special case of fitting size distribution models to empirical data. It combines Bayesian and frequentist statistical approaches with the criterion of model microfoundation, which is to select, all other things considered being equal, the model that comes with a suitable micromodel, that explains, from the perspective of the individual constituent, the genesis of the overall size distribution. The approach is subsequently illustrated with size distribution data on commercial cattle farms in Namibia. We find that the double-Pareto lognormal distribution fits the data best. Our approach might have the potential to reconcile one of the oldest debates in current economics, i.e. the one about the best model to describe and explain the distribution of economic key variables such as income, wealth and city sizes in a country. The second paper revisits the Namibian commercial cattle farm data and uses it to put some theories from the agricultural economics literature regarding farm management under environmental risk to an empirical test. We focus on the relations between inter-annual variability in rainfall (environmental risk), risk preferences, farm size and stocking rate. We demonstrate that the Pareto distribution - which separates the distribution into two parts - is a statistically plausible description of the empirical farm size distribution when ´farm size´ is operationalized by herd size, but not by rangeland area. A statistical group comparison based on the two parts of the Pareto distribution shows that large farms are on average exposed to significantly lower environmental risk. Regarding risk preferences, we do not find any significant differences in mean risk attitude between the two branches. Our analysis confirms the central role of the stocking rate as farm management parameter, and shows that environmental risk and the farmer´s gender are key variables in explaining stocking rates in our data. Paper 3 develops a non-expected-utility approach to decision making under Knightian uncertainty which circumvents some of the conceptual problems of existing approaches. We understand Knightian uncertainty as income lotteries with known payoffs but unknown probabilities in each outcome. Based on seven axioms, we show that there uniquely (up to linear-affine transformations) exists an additive and extensive function from the set of Knightian lotteries to the real numbers that represents uncertainty preferences on the subset of lotteries with fixed positive sum of payoffs over all possible states of the world. We define the concept of uncertainty aversion such that it allows for interpersonal comparison of uncertainty attitudes. Furthermore, we propose Renyi´s (1961) generalized entropy as a one-parameter preference function, where the parameter measures the degree of uncertainty aversion. We illustrate it with a simple decision problem and compare it to other decision rules under uncertainty (maximin, maximax, Laplacian expected utility, minimum regret, Hurwicz).
Human activities have converted natural ecosystems worldwide, mostly for agricultural purposes. This change in land use has been recognized as one of the key drivers causing mass extinction of biodiversity. Yet, there are species which persist particularly in traditional, low-intensity agricultural areas. However, this farmland biodiversity is increasingly threatened by the consequences of land-use intensification and land abandonment. One effect of these two processes is the change in existing landscape structures. This dissertation aimed at quantifying the relationship between biodiversity and landscape structures because a better understanding of current biodiversity patterns and their drivers is needed to navigate biodiversity conservation for a sustainable development. Specifically, this dissertation anticipates the impacts of land-use change on biodiversity in Southern Transylvania, focusing on butterflies and plants as study groups. In a first step, a methodological baseline for subsequent biodiversity studies is developed by exploring an optimal survey strategy, allocating the available resources in a study design that enables high statistical power and covers a wide range of environmental conditions. This study shows that in the highly heterogeneous farmland mosaic of Southern Transylvania, survey effort can be moderately reduced while still showing similar patterns of species richness, species turnover and species composition (Chapter 2). In a second step, biodiversity patterns of plants and butterflies are empirically investigated in response to different landscape structures, particularly towards heterogeneity and woody vegetation cover. These studies provide evidence that all main land-use types in Southern Transylvania, namely arable land, grassland and forests, contribute to an overall landscape pool. Species richness of plants, but not of butterflies, differed significantly between arable land and grassland. Presence of woody vegetation in farmland had a positive effect on plant species richness. Heterogeneity has been found beneficial for butterfly species richness in arable land, but not in grasslands. Species composition of plants was determined by land-use, but butterfly species composition was widely overlapping in arable land and grassland (Chapters 3 & 4). Investigations on the potential spread of invasive plant species in the Transylvanian landscape exhibited that distance to roads and heterogeneity, especially in arable land, were key variables determining the invasibility of the landscape (Chapter 5). By studying movement patterns of butterflies in agricultural landscapes, land-use intensity could be revealed having an impact on butterfly movements. Furthermore, butterflies were found to prefer non-arable patches within farmland (Chapter 6). In a third step, this dissertation conceptually embeds socio-economic considerations into the local and international discourse on sustainable rural development: Reflections on a participatory projects on establishing butterfly monitoring in Romania conclude that involving citizens in biodiversity conservation is possible in Romania, but need tailored approaches which consider the unique social and cultural settings (Chapter 7). Current recommendations from scientific literature to increase the agricultural yield, for example in Eastern European landscapes, through ´sustainable intensification´ for global food security are scrutinized for their engagement with sustainability. This dissertation concludes that genuine sustainable solutions need to respect the various aspects of sustainability, including procedural and distributive justice. Furthermore, it is clarified that general recommendations for agricultural intensification, for instance in Romania, may lead to devastating impacts on biodiversity and ecosystem functions (Chapter 8). This dissertation provides evidence that the beneficial characteristics of the Translvanian farmland are linked to the fine spatial scale of the agricultural mosaic, the amount and distribution of semi-natural elements and the scattered woody vegetation throughout the landscape. Hence, the future of biodiversity depends on human interventions in the ancient cultural landscape. Navigating biodiversity conservation in Southern Transylvania thus needs genuine sustainable solutions, which integrate socially acceptable and ecological meaningful landscape management.
In der vorliegenden Arbeit werden zwei etablierte soziale Dilemmata (Beitragsund Verteilungsdilemma) auf das Feld der Verhandlungsforschung übertragen. Die Parteien mussten entweder über die Verteilung von geteilten Ressourcen oder über den Beitrag zu geteilten Ressourcen in einem integrativen Verhandlungssetting verhandeln. Zusätzlich wurde die Valenz der verhandelten Ressourcen variiert (positive vs. negative Ressourcen). In insgesamt vier Studien wurde demonstriert, dass die Kombination aus Allokationskontext (Beitrag vs. Verteilung) und Ressourcenvalenz (Profite vs. Lasten) zu distinkten regulatorischen Foki führt, welche wiederum die Qualität der Verhandlungsergebnisse beeinflussen. Darüberhinaus wird der Einfluss der regulatorischen Passung in Verhandlungen um Gegenstände mit unterschiedlichen Ergebnisstrukturen gezeigt, sowie die Relevanz der vorliegenden Forschung für die Forschungsfelder der Allmende-, und Sozialen- Dilemma-Forschung diskutiert.
Emotionen sind im Straßenverkehr überproportional vertreten und können negative Auswirkungen auf die Verkehrssicherheit haben. Die am häufigsten untersuchte Emotion in diesem Zusammenhang ist Ärger. Dieser führt zur Einengung der Aufmerksamkeit sowie einer optimistischeren Risikoeinschätzung. Zudem fallen ärgerliche Fahrer durch erhöhte Geschwindigkeiten auf - einer der Hauptursachen von Unfällen. Das Ziel der vorliegenden Arbeit war es, herauszufinden, durch welche kognitiven Bewertungsdimensionen im Sinne der Appraisaltheorie nach Lazarus (1993) Ärger im Straßenverkehr bestimmt wird. Der Fragestellung wurde sich in drei empirischen Schritten genähert. Zu Beginn wurde eine Onlinebefragung mit dem Ziel durchgeführt, einen allgemeinen Überblick darüber zu geben, welche Emotionen im Straßenverkehr auftreten und welche Rolle Ärger dabei spielt. Als Erfassungsmethode des Emotionsspektrums im Straßenverkehr wurde eine Onlinevariante der Vignettenstudie gewählt. Den Probanden wurden zwölf Textvignetten - Verkehrsszenarien in Textform - vorgelegt, in die sie sich hinein versetzen und angeben sollten, welche Emotionen sie dabei empfanden. Die Verkehrssituationen wurden anhand von vier Appraisaldimensionen (Verantwortlichkeit, Zielrelevanz, Zielkongruenz und Vorsatz) erstellt, um den Verkehrsraum in seiner Breite abzubilden. Es konnte bestätigt werden, dass Ärger sowohl die häufigste als auch stärkste Emotion war. Nachdem die Wichtigkeit der Emotion bestätigt werden konnte, wurde in einem zweiten Schritt untersucht, welche weiteren Bewertungskomponenten im Sinne der Appraisaltheorie bei der Entstehung von Ärger im Straßenverkehr eine Rolle spielen. Dafür wurde als Methode eine Simulatorstudie mit anschließendem, qualitativem Interview gewählt. Das vordergründige Ziel war es, die aus der Literatur bekannten Dimensionen auf ihre Relevanz im Kontext Straßenverkehr zu überprüfen und zu erweitern. Neben der Bestätigung der Dimension Zielrelevanz ergaben sich bei den Interviews zwei weitere Bewertungsdimensionen: die wahrgenommene Kontrolle sowie der Grad des Verständnisses für die Blockierung. Sobald eine Person sich den Grund für eine Blockierung vorstellen konnte war der Ärger weniger intensiv. Die Studie zeigte vor allem, dass die objektiven Kriterien einer Situation (z.B. keine Kontrolle gegeben) nicht zwangsläufig die individuellen Bewertungen dieser widerspiegelten, woraus die These eines multiplen Mediatormodells entwickelt und in einer dritten Studie quantitativ getestet wurde. Die Dimensionen Verständnis und Kontrolle wurden daher in objektive Situationsmerkmale und individuelle Bewertungen unterteilt. Das Mediatormodell konnte insgesamt bestätigt werden. Dabei wurde der Ärger (AV) hauptsächlich durch die individuellen Bewertungen (Mediatoren) bestimmt. Der Effekt der externen Manipulation (UV) der Dimensionen Verständnis und Kontrolle wurde fast vollständig über deren individuelle Abbildung vermittelt. Die objektiven Gegebenheiten einer Situation (z.B. Begründung für Verhalten) können zwar die Bewertung beeinflussen, jedoch nicht die Stärke der Emotion direkt vorhersagen. Besonders die Dimension Verständnis zeigte großen Einfluss auf die Intensität - je höher der Grad des Verständnisses, umso geringer der Ärger. Somit beeinflusst das Geben einer Begründung für eine Blockierung im Straßenverkehr das individuelle Verständnis und minimiert den Ärger signifikant. Daraus ergeben sich direkte Anwendungsmöglichkeiten, um Ärger im Straßenverkehr abzuschwächen und das Risiko eines Unfalls zu minimieren.
The concept of corporate entrepreneurship continues to occupy the minds of scholars and practitioners alike. This is not surprising as corporate entrepreneurship constitutes a major driver of organizational revitalization, learning, and growth within large and medium size organizations. However, despite extensive research on corporate entrepreneurship, there is still confusion about the interplay of its macro- and micro-level constituents. To unveil how the structures, practices, and behaviors, which constitute entrepreneurship in large, diversified firms, interact, I utilize a systemic reasoning and link the notion of corporate entrepreneurship to diverse theoretical positions in the strategic management field including intraorganizational ecology, institutional theory, and configuration theory - links that have been so far neglected in the literature on corporate entrepreneurship. I develop my arguments in three complementary articles. In the first article, I provide a review of the theoretical framework that to a large extent underpins my research: the Bower-Burgelman process model. In the second article, I take a qualitative case study approach to analyze how micro-level practices affect the intraorganizational and external environment in favor of an entrepreneurial initiative. In the third article, I identify four different design types on the basis of a qualitative meta-synthesis, which reflect coherent constellations of managerial interpretive-schemes, structures, and systems that cultivate entrepreneurial behavior. In sum, this dissertation contributes to a new understanding of corporate entrepreneurship as a system of entrepreneurially behaving actors who are constrained and simultaneously enabled by a set of social, cultural, political, and structural context factors.