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This study presents a high-throughput (HTP) micronucleus assay in multi-well plates with an automated evaluation for risk assessment applications. The evaluation of genotoxicity via the micronucleus assays according to international guidelines ISO 21427-2 with Chinese hamster (Cricetulus griseus) V79 cells was the starting point to develop our methodology. A drawback of this assay is that it is very time consuming and cost intensive. Our HTP micronucleus assay in a 48-well plate format allows for the simultaneous assessment of five different sample-concentrations with additional positive, negative and solvent controls with six technical replicates each within a quarter of the time required for the equivalent evaluation using the traditional slide method. In accordance with the 3R principle, animal compounds should be replaced with animal-free alternatives. However, traditional cell culture-based methods still require animal derived compounds like rat-liver derived S9-fraction, which is used to simulate the mammalian metabolism in in vitro assays that do show intrinsic metabolization capabilities. In the present study, a recently developed animal-free biotechnological alternative (ewoS9R) was investigated in the new high-throughput micronucleus assay. In total, 12 different mutagenic or genotoxic chemicals were investigated to assess the potential use of the animal-free metabolization system (ewoS9R) in comparison to a common rat derived product. Out of the 12 compounds, one compound did not induce micronuclei in any treatment and 2 substances showed a genotoxic potential without the need for a metabolization system. EwoS9R demonstrated promising potential for future applications as it shows comparable results to the rat-derived S9 for 6 of the 9 pro-genotoxic substances tested. The remaining 3 substances (2-Acetamidofluorene, Benzo[a]pyrene, Cyclophosphamide) were only metabolized by rat-derived S9. A potential explanation is that ewoS9R was investigated with an approx. 10-fold lower enzyme concentration and was only optimized for CYP1A metabolization that may be improved with a modified production procedure. Future applications of ewoS9R go beyond the micronucleus assay, but further research is necessary.

Achieving a more sustainable lifestyle is one of the most important challenges of the 21st century. Sustainable development, therefore, is one of the key objectives also for industrial nations such as Germany. Sustainable development is defined as the "development that meets the needs of the present without compromising the ability of future generations to meet their own needs" (WCED 1987, Chapter 2). This development, however, is not only based on environmental dimensions but also on economic and social dimensions. These are known as the three pillars of sustainability. According to the Global Sustainable Development Report (Messerli et al. 2019), there are four levers of transformation being most important to achieve sustainable development, one of which is science and technology. Information systems (IS) research investigates the application of information technology in organizational settings (Hevner et al. 2004). IS research considers itself as a socio-technical discipline (Briggs et al. 2010), which should investigate IS-related issues along a social-technical continuum (Sarker et al. 2019). In recent times, the field is discussing more intensively the application of IS for sustainability purposes (e.g., Melville 2010; Watson et al. 2010; Henkel and Kranz 2018). However, IS scholars claim for more work to be done regarding sustainable development (Seidel et al. 2017; Gholami et al. 2016; Parmiggiani and Monteiro 2018) and to develop knowledge along the social-technical continuum (Sarker et al. 2019). For this reason, the aim of this dissertation is to develop knowledge for IS to achieve sustainable development from different socio-technical perspectives. Therefore, this work applies pluralistic methodological approaches (qualitative methods, e.g., semi-structured interviews, and quantitative methods, e.g., data collection from a field study or online experiments). The theoretical contribution of this dissertation expands existing design knowledge in the field of IS for sustainability. Following Gregor and Hevner (2013), design knowledge can be grouped into two types: descriptive and prescriptive knowledge. On the one hand, descriptive knowledge contributes to the knowledge about natural phenomena and the sense-making relationships between phenomena (what). Descriptive knowledge provides the scientific base for the world we live in. On the other hand, prescriptive knowledge contributes to the knowledge about man-made artifacts to improve our world (how). Design theories are an abstract and coherent body of knowledge, which include both types of knowledge (Gregor and Hevner 2013). Overall, this work takes three different perspectives to develop both types of knowledge: the socio-technical perspective, the sociocentric perspective, and the technocentric perspective. First, to contribute to the socio-technical perspective, this thesis presents new approaches to analyze and improve individual driving behavior in individual road traffic. Personal traffic accounts for approximately 11% of carbon dioxide (CO2) emissions globally (Andor et al. 2020). Environmental driving behavior, therein, has a significant impact on the fuel consumption of vehicles (Lárusdóttir and Ulfarsson 2014), and reductions of fuel consumption up to 30% are possible. One promising approach to improve individual driving behavior is the application of eco-feedback to the driver. Therefore, this thesis presents prescriptive knowledge in the form of design artifacts for mobile eco-driving feedback information systems (EDFIS), which results from justificatory knowledge, a prototypical instantiation of a mobile EDFIS, and its application within a field study. The results indicate that eco-feedback affects environmentally friendly driving behavior. However, eco-feedback seems not to address all aspects of eco-driving behavior. Nowadays, the Internet-of-Things (IoT) has reached cars, and ever more embedded sensors allow for rich data analysis of individual driving behavior. Therefore, this thesis presents a factor model describing IoT-measured individual driving behavior to handle the resulting amount of IoT-data and analyzes the effect of eco-feedback on individual driving behavior. Second, to contribute to the sociocentric perspective, this thesis presents design knowledge on how to design social media platforms in order to counteract so-called fake news. Such misleading information – which has always been a problem but has recently found nutritious ground in social media – poses a major threat. In recent times, fake news is spread to impact political decision-making and elections. However, fake news is not only a challenge for politics but also for ecologically and economically sustainable development. For instance, fake news is spread to influence financial markets in order to affect the financial value of stocks and options (Maasberg et al. 2018). Furthermore, fake news is a popular means to undermine climate change, which in reality requires significant changes in the individual and collective behavior of people (van der Linden et al. 2017). This thesis presents two new approaches to empower people individually to recognize and report misleading information to counteract the spread of fake news. Firstly, related articles are an appropriate tool to improve social media users' ability to recognize fake news as such. Especially, the application of controversial related articles shows the best results. Secondly, social norm messages are an appropriate tool to encourage social media users to report fake news. This allows social media providers to effectively identify and remove misleading and deceptive information from their platforms. To contribute to the third and last, technocentric perspective, this thesis presents a new approach to analyze and design lean, digitally supported value creation processes in companies and organizations. In the light of ever more connected entities and the diffusion of digital technologies, innovative information flows enable various potentials in value creation processes and allow minimizing waste. For instance, rich information availability allows production with fewer resources or the more accurate usage of perishable materials. The presented Value Stream Modeling and Notation (VSMN) constitutes a domain-specific modeling language, which supports designers of economically sustainable value creation processes in times of digitalization. For evaluation purposes, we present, among others, the results of the application of VSMN while designing lean material logistics processes in hospitals. The results also constitute prescriptive knowledge for material logistic processes in hospitals, which are more efficient due to the targeted use of digital technologies. To sum up, this dissertation presents design knowledge – including both types, descriptive and prescriptive knowledge – and contributes to the knowledge base about IS for sustainability (Gholami et al. 2016; Seidel et al. 2017; Parmiggiani and Monteiro 2018) and sustainable development (Messerli et al. 2019). In addition, the thesis develops design knowledge along the social-technical continuum (Sarker et al. 2019). Using methodological pluralistic (qualitative and quantitative) approaches allows an extension of the existing knowledge from different perspectives (Venkatesh et al. 2013). Overall, the results of this thesis contribute to overcoming one of the greatest challenges of mankind and the greatest challenge of the 21st century.

Faktoren wie Globalisierung, Liberalisierung und verbesserte Produktionsfaktoren fungieren in den letzten Jahrzehnten als Treiber für ein kontinuierliches Wachstum im kommerziellen Luftverkehr. Dementsprechend ist auch die Steuerung des operativen Betriebes der einzelnen Fluggesellschaften durch ihre Verkehrszentralen immer komplexer und aufwändiger geworden. Störereignisse und deren Auswirkungen treffen die im starken Wettbewerb stehenden Fluggesellschaften heute härter denn je zuvor, so dass ein dringender Bedarf zur besseren Unterstützung von Entscheidungen innerhalb der Verkehrszentrale zur Reduktion von zusätzlichen Kosten existiert. Im Rahmen der vorliegenden Arbeit werden methodische Ansätze diskutiert, um die bisher überwiegend theoretisch existierenden und kaum genutzten Entscheidungsunterstützungssysteme zu praxistauglichen Systemen auszubauen. Insbesondere aus technologischer und funktionaler Sicht sind trotz der intensiven Forschung in den letzten 30 Jahren keine großen Veränderungen zu registrieren, da Annahmen über die unternehmerische Praxis regelmäßig zu sehr vereinfacht und zu wenig verallgemeinert werden. Durch die vorliegende Arbeit werden die Aufgaben, Organisationsgestaltung sowie Informationsund Kommunikationssysteme innerhalb der Verkehrszentrale systematisch dargestellt. Sowohl die Identifikation von Handlungsoptionen sowie den Rahmenbedingungen und dem Zusammenspiel einzelner Akteure sind von zentraler Bedeutung, um zu verstehen, wie Funktionsbereiche und Entscheider ihre täglichen Aufgaben erfüllen. Aufbauend auf diesen Erkenntnissen werden relevante Anwendungsfälle und Anforderungen abgeleitet. Gerade die Vielzahl möglicher Modelle und Algorithmen aus dem Bereich der mathematischen Optimierung, welche bereits durch die Forschungsarbeiten thematisiert worden sind, werden erneut durch diese Arbeit bewertet und weiterführend analysiert. Denn nur allgemeingültige und flexible Ansätze können dabei unterschiedlichen Fluggesellschaften mit möglichst geringen Anpassungen adressieren. Die Ergebnisse dieser Arbeit stützen sich zum großen Teil auf den Erkenntnissen, die im Rahmen eines vierjährigen Forschungsprojektes mit einem aus mehreren verschiedenen Fluggesellschaften bestehenden Konzern erarbeitet wurden. Im Rahmen der Kooperation ist als Ergebnis ein praxistaugliches Entscheidungsunterstützungssystem auf Basis dieser Arbeit entstanden, welches sich bereits parallel in zwei Verkehrszentralen des Forschungspartners im produktiven Betrieb befindet. Damit das Tool für weitere Fluggesellschaften innerhalb des Konzerns einfach ausgerollt werden kann, wurde die Optimierungslogik soweit wie möglich mittels eines Geschäftsregel- Managementsystems entkoppelt.

Dissertation, RWTH Aachen University, 2018; Aachen 1 Online-Ressource (XVI, 125 Seiten) : Illustrationen (2018). = Dissertation, RWTH Aachen University, 2018, The increasing industrialization and growth of population has led to an increase in the global energy and fuel demand, particularly in the transportation sector. However, the use of established fossil fuels, such as petroleum-derived diesel fuels, also poses a significant risk for the environment and the global climate. Therefore, research and development on alternative and renewable fuels is increasing rapidly. Biomass-derived fuels, so called biofuels, represent a promising alternative to fossil fuels. Biofuels are assumed to be more environmental friendly and sustainable than fossil fuels, particularly as they reduce greenhouse gas emissions, which are a positive influence on the global climate,. However, an important factor, the toxicity of these novel fuels, is often not considered. While the toxic potency of fossil fuels is largely known, almost no information with regard to the toxicity of biofuels is available. Results on the toxic potency of biofuel candidates can be integrated in the fuel development process and provide important information on potentially hazardous biofuels. Therefore, the aim of the present research was to investigate the applicability of an effect-based “Green Toxicology” approach as part of the development of novel biofuels within the DFG Cluster of Excellence “Tailor-made Fuels from Biomass” (TMFB). The potential biofuels investigated in this “Green Toxicology” approach were the furan 2-Methylfuran (2-MF), the tetrahydrofurans 2-Methyltetrahydrofuran (2-MTHF), 3-Methyltetrayhydrofuran (3-MTHF) and 2-Butyltetrahydrofuran (2-BTHF), the ether Di-n-butyl ether (DNBE), the ketones Methyl isopropyl ketone (MIPK) and 2-Butanone (MEK), the alcohol 1-Octanol (1-Oct), and the biohybrid fuels Dimethoxymethane (DMM) and Diethoxymethane (DEM). The testing of these biofuel candidates required a number of adaptions to the standardized test systems due to some special phyisco-chemical properties, which have been identified in the first part of this thesis. Briefly, the high volatility of some biofuel candidates as well as their tendency to solve plastics were addressed in modifications of the test systems, e.g., by sealing test systems and replacing plastic materials with glass materials. Methods for chemical analyses of the actual concentrations were established for validation of these modifications. In the second part of this research, toxicity testing of the biofuel candidates was performed with regard to their acute toxicity for Daphnia magna and Danio rerio as well as their genotoxicity for V79 cells was performed. The modified acute immobilisation assay with Daphnia magna and the modified Fish Embryo Toxicity (FET) test with Danio rerio embryos provide important information on the relative aquatic toxic potency of the biofuel candidates. The biofuel candidates 1-Oct, DNBE, 2-BTHF and 2-MF were found to induce a strong acute toxic potency. Moreover, 1-Oct and 2-MF induced very strong genotoxic effects, with 2-MF being the most potent inducer. 2-MTHF, 3-MTHF, MIPK, MEK, DMM and DEM induced only weak toxic effects in high concentrations that are not biologically relevant. Therefore, it is recommended that further biofuel development focus on the latter biofuel candidates that exhibited weaker toxic effects. Besides the investigation into the toxic potency of the biofuel candidates, two in silico prediction tools, the OECD QSAR-Toolbox and the Ecological Structure Activity Relationship (ECOSAR) predictive model, were investigated with regard to their applicability as part of the “Green Toxicology” approach. The OECD QSAR toolbox was used for the prediction of biofuels with high risks with respect to their ability to induce genotoxicity based on structural characteristics of the investigated substances and their metabolites. However, a comparison of experimental and predicted results from QSAR toolbox revealed discrepancies between the predicted and the observed genotoxicity of the biofuel candidates; the ECOSAR predictive model was used for prediction of the aquatic toxicity of the biofuel candidates, but it was found to overestimate the toxicity of many substances. Nonetheless, the ECOSAR predictive model could still be used estimating for an initial screening of new substances that might require experimental testing. In addition to the toxicity assessment of the biofuel candidates, methods for a reliable investigation of established fossil reference fuels, such as diesel fuel, were investigated. Fossil fuels are complex mixtures that cannot easily be tested in (eco)toxicological test systems. This challenge was addressed by establishing a passive dosing approach facilitated by silicone tubes in an aqueous phase/exposure system. Results from the passive dosing approach indicated a significantly lower toxicity of all biofuel candidates compared to fossil fuels for daphnids exposures. However, further improvements to this passive dosing approach, in particular with regard to the chemical analyses, are required. The results of the present research demonstrate that effect-based bioassays can provide important information for biofuel development and that a “Green Toxicology” approach can be successfully integrated into the fuel design process. The identification of the potentially hazardous biofuel candidates 2-MF, 1-Oct, DNBE and 2-BTHF suggest that focus should be towards the much less toxic biofuel candidates 2-MTHF, 3-MTHF, MIPK, MEK, DMM and DEM., Published by Aachen