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Captive Red Army soldiers made up the majority of victims of Nazi Germany’s starvation policy against Soviet civilians and other non-combatants and thus constituted the largest single victim group of the German war of annihilation against the Soviet Union. Indeed, Soviet prisoners of war were the largest victim group of all National Socialist annihilation policies after the European Jews. Before the launch of Operation Barbarossa, it was clear to the Wehrmacht planning departments on exactly what scale they could expect to capture Soviet troops. Yet, they neglected to make the necessary preparations for feeding and sheltering the captured soldiers, who were viewed by the economic staffs and the military leadership alike as direct competitors of German troops and the German home front for precious food supplies. The number of extra mouths to feed was incompatible with German war aims. The obvious limitations on their freedom of movement and the relative ease with which large numbers could be segregated and their rations controlled were crucial factors in the death of over 3 million Soviet POWs, the vast majority directly or indirectly as a result of deliberate policies of neglect, undernourishment, and starvation while in the ‘care’ of the Wehrmacht. The most reliable figures for the mortality of Soviet POWs in German captivity reveal that up to 3.3 million died from a total of just over 5.7 million captured between June 1941 and February 1945 — a proportion of almost 58 percent. Of these, 2 million were already dead by the beginning of February 1942. In English, there is still neither a single monograph nor a single edited volume dedicated to the subject. This article now provides the first detailed stand-alone synthesis in that language addressing the whole period from 1941 to 1945.
Begrenztes Cottbus?
(2024)
In diesem Band ermöglicht Mario Kaun ausgewählte Einblicke in die Lebenswelt der Cottbuser Exklavengesellschaft des 18. Jahrhunderts. Erstmalig erscheint hiermit für diesen Untersuchungsraum eine grundlegende Studie, die in umfassender Weise die Exklave und das Verhältnis von Militär und Gesellschaft näher erforscht sowie die wirtschaftliche Funktion der Garnison in einer aufstrebenden Stadt kritisch hinterfragt. Der Autor lenkt hierbei das Augenmerk auf etliche, bisher völlig unbekannte Perspektiven, die darüber hinaus einen wichtigen Beitrag zur Stadt- und Regionalgeschichtsforschung von Cottbus und der Niederlausitz leisten. Insbesondere die Befassung mit der brandenburgisch-preußischen Exklave stellt eine wertvolle Ergänzung zur bislang rudimentären Forschungslage dar.
The inclusion of exotic germplasm serves as a crucial means to enhance allelic and
consequently phenotypic diversity in inbred crop species. Such species have experienced a reduction in diversity due to artificial selection focused on a limited set of traits. The natural biodiversity within ecosystems presents an opportunity to explore various traits influencing plant survival, reproductive fitness and yield potential. In agricultural research, the study of wild species closely related to cultivated plants serves as a means to comprehend the genetic foundations of past domestication events and the polymorphisms essential for future breeding efforts to develop superior varieties. In order to examine the metabolic composition, pinpoint quantitative trait loci (QTL) and facilitate their resolution an extensive large-scale analysis of metabolic QTL (mQTL) was conducted on tomato backcross inbred lines (BILs) derived from a cross between the wild species S. pennellii (5240) incorporated into the background of S. lycopersicum cv. LEA determinate inbred which can be grown in open fields and cv. TOP indeterminate which can be grown in greenhouse conditions. A large number of mQTL associated with primary secondary and lipid metabolism in fruit were identified across the two BIL populations. Epistasis, the interactions between genes at different loci, has been an interest in molecular and quantitative genetics for many decades. The study of epistasis requires the analysis of very large populations with multiple independent genotypes that carry specific genomic regions. In order to understand the genetic basis of tomato fruit metabolism, I extended the work to investigate epistatic interactions of the genomic regions. In addition, two candidate genes were identified through quantitative trait loci underlying fruit-specific sucrose and jasmonic acid derivatives. Finally, in this study, I assessed the genetic framework of fruit metabolic traits with a high level of detail, utilizing the newly created Solanum pennellii (5240) backcrossed introgression lines (n=3000). This investigation resulted in the discovery of promising candidate loci associated with significant fruit quality traits, including those to the abundance of glutamic acid and aspartic acid crucial elements contributing to the development of acidity and flavors.
Diese Arbeit zeigt auf, wie historisch und rechtlich eine Ungleichheit zwischen Schwarzen und Weißen in Deutschland gewachsen ist und geht der Frage nach, welche Anforderungen das Verfassungsrecht, die Rechtspraxis und die Politik erfüllen müssen, um sie auszugleichen.
Eingangs wird die Entwicklung des Verbots der rassischen Diskriminierung im internationalen und nationalen Recht dargelegt. Folglich zeichnet die Verfasserin die Diskriminierungsgeschichte von Schwarzen Menschen nach. Zur Überwindung der nach wie vor bestehenden strukturellen Diskriminierung schlägt sie ein positives Recht vor, das sich auf Menschenrechtsstandards und Lösungsansätzen aus Rechtsvergleichen stützt und die Gleichberechtigung von Schwarzen Menschen bewirken soll.
HPI Future SOC Lab
(2024)
The “HPI Future SOC Lab” is a cooperation of the Hasso Plattner Institute (HPI) and industry partners. Its mission is to enable and promote exchange and interaction between the research community and the industry partners.
The HPI Future SOC Lab provides researchers with free of charge access to a complete infrastructure of state of the art hard and software. This infrastructure includes components, which might be too expensive for an ordinary research environment, such as servers with up to 64 cores and 2 TB main memory. The offerings address researchers particularly from but not limited to the areas of computer science and business information systems. Main areas of research include cloud computing, parallelization, and In-Memory technologies.
This technical report presents results of research projects executed in 2020. Selected projects have presented their results on April 21st and November 10th 2020 at the Future SOC Lab Day events.
Der Fall des T. Annius Milo bietet für den Lateinunterricht großes didaktisches Potenzial. Denn an seinem Beispiel kann die Lektüre eines lateinischen Textes hervorragend mit realienkundlichen Aspekten verknüpft und es können plausible Bezüge zur Gegenwart hergestellt werden. Die vorliegende Masterarbeit zeigt, welch reiches Themenspektrum in Ciceros Rede Pro Milone steckt. Dazu zählen der historische Kontext des Falls, der Tatbestand des Mordes und der Ablauf des damaligen Gerichtsverfahrens. Darüber hinaus wird das römische Recht mit dem heutzutage in Deutschland geltenden Strafrecht verglichen. Und zu guter Letzt wird hier die Glaubwürdigkeit verschiedener schriftlicher Zeugnisse geprüft, insbesondere die Frage, ob die überlieferte Rede das einstige Prozessgeschehen in authentischer Weise widerspiegelt.
Diglossic translanguaging
(2024)
This book examines how German-speaking Jews living in Berlin make sense and make use of their multilingual repertoire. With a focus on lexical variation, the book demonstrates how speakers integrate Yiddish and Hebrew elements into German for indexing belonging and for positioning themselves within the Jewish community. Linguistic choices are shaped by language ideologies (e.g., authenticity, prescriptivism, nostalgia). Speakers translanguage when using their multilingual repertoire, but do so in a diglossic way, using elements from different languages for specific domains
Der vorliegende Beitrag, der sich weniger als Fachbeitrag, sondern vielmehr als Erfahrungsbericht aus der Praxis versteht, berichtet von unterschiedlichen Versuchen, die Mensch-Tier-Beziehung in den schulischen Kontext einzubringen und somit der unzureichenden Beachtung der Thematik entgegenzuwirken. Nachdem überblicksartig die Relevanz der Mensch-Tier-Thematik herausgestellt und auf diese Weise die Notwendigkeit einer unterrichtlichen Beschäftigung mit dem Verhältnis von Menschen und anderen Tieren begründet wird, wird zunächst von einem ersten Versuch berichtet, (angehende) Lehrkräfte im Rahmen eines Workshops am Studienseminar Potsdam für die Relevanz der Mensch-Tier-Thematik zu sensibilisieren sowie über eine mögliche Umsetzung in den verschiedenen Unterrichtsfächern zu informieren. Anschließend werden – exemplarisch für den Politikunterricht – zwei Unterrichtsstunden, die die Mensch-Tier-Beziehung auf verschiedene Weise in den Politikunterricht einbeziehen, sowie die im Rahmen der Durchführung gesammelten Erfahrungen vorgestellt.
Wem wird geglaubt und wem nicht? Wessen Wissen wird weitergegeben und wessen nicht? Wer hat eine Stimme und wer nicht? Theorien der epistemischen Ungerechtigkeit befassen sich mit dem breiten Feld der ungerechten oder unfairen Behandlung, die mit Fragen des Wissens, Verstehens und Kommunizierens zusammenhängen, wie z.B. die Möglichkeit, vom Wissen oder von kommunikativen Praktiken ausgeschlossen zu werden oder zum Schweigen gebracht zu werden, aber auch Kontexte, in denen die Bedeutungen mancher systematisch verzerrt oder falsch gehört und falsch dargestellt werden, in denen manchen misstraut wird oder es an epistemischer Handlungsfähigkeit mangelt. In diesem Buch wird eine Übersicht über die breite Debatte epistemischer Ungerechtigkeit, epistemischer Unterdrückung und epistemischer Gewalt gegeben, in dem unterschiedliche Theorien, die sich auf der Schnittstelle von Gerechtigkeitstheorie und epistemischen Fragen befinden, systematisch und kritisch diskutiert sowie theoretische Vorgänger dieser Theorien beleuchtet werden.
In the debate on epistemic injustice, it is generally assumed that testimonial injustice as one form of epistemic injustice cannot be committed (fully) deliberately or intentionally because it involves unconscious identity prejudices. Drawing on the case of sexual violence against refugees in European refugee camps, this paper argues that there is a form of testimonial injustice—willful testimonial injustice—that is deliberate. To do so, the paper argues (a) that the hearer intentionally utilizes negative identity prejudices for a particular purpose and (b) that the hearer is aware of the fact that the intentionally used prejudices are in fact prejudices. Furthermore, the paper shows how testimonial injustice relates to recognition failures both in terms of a causal as well as a constitutive claim. In fact, introducing willful testimonial injustice can support the constitutive claim of such a relation that has so far received little attention. Besides arguing for a novel form of testimonial injustice and contributing to the recent debate on the relation between epistemic injustice and recognition failures, this paper is also motivated by the attempt to draw attention to the inhumane conditions for refugees at the border of Europe as well as elsewhere.
Global warming, driven primarily by the excessive emission of greenhouse gases such as carbon dioxide into the atmosphere, has led to severe and detrimental environmental impacts. Rising global temperatures have triggered a cascade of adverse effects, including melting glaciers and polar ice caps, more frequent and intense heat waves disrupted weather patterns, and the acidification of oceans. These changes adversely affect ecosystems, biodiversity, and human societies, threatening food security, water availability, and livelihoods. One promising solution to mitigate the harmful effects of global warming is the widespread adoption of solar cells, also known as photovoltaic cells. Solar cells harness sunlight to generate electricity without emitting greenhouse gases or other pollutants. By replacing fossil fuel-based energy sources, solar cells can significantly reduce CO2 emissions, a significant contributor to global warming. This transition to clean, renewable energy can help curb the increasing concentration of greenhouse gases in the atmosphere, thereby slowing down the rate of global temperature rise.
Solar energy’s positive impact extends beyond emission reduction. As solar panels become more efficient and affordable, they empower individuals, communities, and even entire nations to generate electricity and become less dependent on fossil fuels. This decentralized energy generation can enhance resilience in the face of climate-related challenges. Moreover, implementing solar cells creates green jobs and stimulates technological innovation, further promoting sustainable economic growth. As solar technology advances, its integration with energy storage systems and smart grids can ensure a stable and reliable energy supply, reducing the need for backup fossil fuel power plants that exacerbate environmental degradation.
The market-dominant solar cell technology is silicon-based, highly matured technology with a highly systematic production procedure. However, it suffers from several drawbacks, such as: 1) Cost: still relatively high due to high energy consumption due to the need to melt and purify silicon, and the use of silver as an electrode, which hinders their widespread availability, especially in low-income countries. 2) Efficiency: theoretically, it should deliver around 29%; however, the efficiency of most of the commercially available silicon-based solar cells ranges from 18 – 22%. 3) Temperature sensitivity: The efficiency decreases with the increase in the temperature, affecting their output. 4) Resource constraints: silicon as a raw material is unavailable in all countries, creating supply chain challenges.
Perovskite solar cells arose in 2011 and matured very rapidly in the last decade as a highly efficient and versatile solar cell technology. With an efficiency of 26%, high absorption coefficients, solution processability, and tunable band gap, it attracted the attention of the solar cells community. It represented a hope for cheap, efficient, and easily processable next-generation solar cells. However, lead toxicity might be the block stone hindering perovskite solar cells’ market reach. Lead is a heavy and bioavailable element that makes perovskite solar cells environmentally unfriendly technology. As a result, scientists try to replace lead with a more environmentally friendly element. Among several possible alternatives, tin was the most suitable element due to its electronic and atomic structure similarity to lead.
Tin perovskites were developed to alleviate the challenge of lead toxicity. Theoretically, it shows very high absorption coefficients, an optimum band gap of 1.35 eV for FASnI3, and a very high short circuit current, which nominates it to deliver the highest possible efficiency of a single junction solar cell, which is around 30.1% according to Schockly-Quisser limit. However, tin perovskites’ efficiency still lags below 15% and is irreproducible, especially from lab to lab. This humble performance could be attributed to three reasons: 1) Tin (II) oxidation to tin (IV), which would happen due to oxygen, water, or even by the effect of the solvent, as was discovered recently. 2) fast crystallization dynamics, which occurs due to the lateral exposure of the P-orbitals of the tin atom, which enhances its reactivity and increases the crystallization pace. 3) Energy band misalignment: The energy bands at the interfaces between the perovskite absorber material and the charge selective layers are not aligned, leading to high interfacial charge recombination, which devastates the photovoltaic performance. To solve these issues, we implemented several techniques and approaches that enhanced the efficiency of tin halide perovskites, providing new chemically safe solvents and antisolvents. In addition, we studied the energy band alignment between the charge transport layers and the tin perovskite absorber.
Recent research has shown that the principal source of tin oxidation is the solvent known as dimethylsulfoxide, which also happens to be one of the most effective solvents for processing perovskite. The search for a stable solvent might prove to be the factor that makes all the difference in the stability of tin-based perovskites. We started with a database of over 2,000 solvents and narrowed it down to a series of 12 new solvents that are suitable for processing FASnI3 experimentally. This was accomplished by looking into 1) the solubility of the precursor chemicals FAI and SnI2, 2) the thermal stability of the precursor solution, and 3) the potential to form perovskite. Finally, we show that it is possible to manufacture solar cells using a novel solvent system that outperforms those produced using DMSO. The results of our research give some suggestions that may be used in the search for novel solvents or mixes of solvents that can be used to manufacture stable tin-based perovskites.
Due to the quick crystallization of tin, it is more difficult to deposit tin-based perovskite films from a solution than manufacturing lead-based perovskite films since lead perovskite is more often utilized. The most efficient way to get high efficiencies is to deposit perovskite from dimethyl sulfoxide (DMSO), which slows down the quick construction of the tin-iodine network that is responsible for perovskite synthesis. This is the most successful approach for achieving high efficiencies. Dimethyl sulfoxide, which is used in the processing, is responsible for the oxidation of tin, which is a disadvantage of this method. This research presents a potentially fruitful alternative in which 4-(tert-butyl) pyridine can substitute dimethyl sulfoxide in the process of regulating crystallization without causing tin oxidation to take place. Perovskite films that have been formed from pyridine have been shown to have a much-reduced defect density. This has resulted in increased charge mobility and better photovoltaic performance, making pyridine a desirable alternative for use in the deposition of tin perovskite films.
The precise control of perovskite precursor crystallization inside a thin film is of utmost importance for optimizing the efficiency and manufacturing of solar cells. The deposition process of tin-based perovskite films from a solution presents difficulties due to the quick crystallization of tin compared to the more often employed lead perovskite. The optimal approach for attaining elevated efficiencies entails using dimethyl sulfoxide (DMSO) as a medium for depositing perovskite. This choice of solvent impedes the tin-iodine network’s fast aggregation, which plays a crucial role in the production of perovskite. Nevertheless, this methodology is limited since the utilization of dimethyl sulfoxide leads to the oxidation of tin throughout the processing stage. In this thesis, we present a potentially advantageous alternative approach wherein 4-(tert-butyl) pyridine is proposed as a substitute for dimethyl sulfoxide in regulating crystallization processes while avoiding the undesired consequence of tin oxidation. Films of perovskite formed using pyridine as a solvent have a notably reduced density of defects, resulting in higher mobility of charges and improved performance in solar applications. Consequently, the utilization of pyridine for the deposition of tin perovskite films is considered advantageous.
Tin perovskites are suffering from an apparent energy band misalignment. However, the band diagrams published in the current body of research display contradictions, resulting in a dearth of unanimity. Moreover, comprehensive information about the dynamics connected with charge extraction is lacking. This thesis aims to ascertain the energy band locations of tin perovskites by employing the kelvin probe and Photoelectron yield spectroscopy methods. This thesis aims to construct a precise band diagram for the often-utilized device stack. Moreover, a comprehensive analysis is performed to assess the energy deficits inherent in the current energetic structure of tin halide perovskites. In addition, we investigate the influence of BCP on the improvement of electron extraction in C60/BCP systems, with a specific emphasis on the energy factors involved. Furthermore, transient surface photovoltage was utilized to investigate the charge extraction kinetics of frequently studied charge transport layers, such as NiOx and PEDOT as hole transport layers and C60, ICBA, and PCBM as electron transport layers. The Hall effect, KP, and TRPL approaches accurately ascertain the p-doping concentration in FASnI3. The results consistently demonstrated a value of 1.5 * 1017 cm-3. Our research findings highlight the imperative nature of autonomously constructing the charge extraction layers for tin halide perovskites, apart from those used for lead perovskites.
The crystallization of perovskite precursors relies mainly on the utilization of two solvents. The first one dissolves the perovskite powder to form the precursor solution, usually called the solvent. The second one precipitates the perovskite precursor, forming the wet film, which is a supersaturated solution of perovskite precursor and in the remains of the solvent and the antisolvent. Later, this wet film crystallizes upon annealing into a full perovskite crystallized film. In our research context, we proposed new solvents to dissolve FASnI3, but when we tried to form a film, most of them did not crystallize. This is attributed to the high coordination strength between the metal halide and the solvent molecules, which is unbreakable by the traditionally used antisolvents such as Toluene and Chlorobenzene. To solve this issue, we introduce a high-throughput antisolvent screening in which we screened around 73 selected antisolvents against 15 solvents that can form a 1M FASnI3 solution. We used for the first time in tin perovskites machine learning algorithm to understand and predict the effect of an antisolvent on the crystallization of a precursor solution in a particular solvent. We relied on film darkness as a primary criterion to judge the efficacy of a solvent-antisolvent pair. We found that the relative polarity between solvent and antisolvent is the primary factor that affects the solvent-antisolvent interaction. Based on our findings, we prepared several high-quality tin perovskite films free from DMSO and achieved an efficiency of 9%, which is the highest DMSO tin perovskite device so far.
Knowledge about causal structures is crucial for decision support in various domains. For example, in discrete manufacturing, identifying the root causes of failures and quality deviations that interrupt the highly automated production process requires causal structural knowledge. However, in practice, root cause analysis is usually built upon individual expert knowledge about associative relationships. But, "correlation does not imply causation", and misinterpreting associations often leads to incorrect conclusions. Recent developments in methods for causal discovery from observational data have opened the opportunity for a data-driven examination. Despite its potential for data-driven decision support, omnipresent challenges impede causal discovery in real-world scenarios. In this thesis, we make a threefold contribution to improving causal discovery in practice.
(1) The growing interest in causal discovery has led to a broad spectrum of methods with specific assumptions on the data and various implementations. Hence, application in practice requires careful consideration of existing methods, which becomes laborious when dealing with various parameters, assumptions, and implementations in different programming languages. Additionally, evaluation is challenging due to the lack of ground truth in practice and limited benchmark data that reflect real-world data characteristics.
To address these issues, we present a platform-independent modular pipeline for causal discovery and a ground truth framework for synthetic data generation that provides comprehensive evaluation opportunities, e.g., to examine the accuracy of causal discovery methods in case of inappropriate assumptions.
(2) Applying constraint-based methods for causal discovery requires selecting a conditional independence (CI) test, which is particularly challenging in mixed discrete-continuous data omnipresent in many real-world scenarios. In this context, inappropriate assumptions on the data or the commonly applied discretization of continuous variables reduce the accuracy of CI decisions, leading to incorrect causal structures.
Therefore, we contribute a non-parametric CI test leveraging k-nearest neighbors methods and prove its statistical validity and power in mixed discrete-continuous data, as well as the asymptotic consistency when used in constraint-based causal discovery. An extensive evaluation of synthetic and real-world data shows that the proposed CI test outperforms state-of-the-art approaches in the accuracy of CI testing and causal discovery, particularly in settings with low sample sizes.
(3) To show the applicability and opportunities of causal discovery in practice, we examine our contributions in real-world discrete manufacturing use cases. For example, we showcase how causal structural knowledge helps to understand unforeseen production downtimes or adds decision support in case of failures and quality deviations in automotive body shop assembly lines.
Portal Transfer 2024
(2024)
Liebe Leserinnen und Leser, die eigene „Blase“ verlassen, Perspektiven wechseln, Silo-Mentalität überwinden – was der Wissenschaft in ihrem Innern gelingt, ja gelingen muss, um erfolgreich zu sein, stellt sie in ihrer Außenwirkung noch immer vor Herausforderungen. Dabei gehört es doch inzwischen zum Selbstverständnis moderner Universitäten, öffentlich zu erklären, woran in ihren Räumen geforscht wird, sich in gesellschaftliche Diskurse einzubringen und ihre Erkenntnisse zügig in die Praxis zu überführen.
Die Universität Potsdam hat diese Transferaufgaben neben Lehre und Forschung als dritte Säule installiert und ihrem Gebäude damit noch mehr Stabilität verliehen. Seit Jahren gehört sie im nationalen Vergleich zu den erfolgreichsten Hochschulen, wenn es darum geht, Start-ups zu fördern und aus der Forschung heraus Unternehmen zu gründen: In diesem Magazin berichten wir von der Potassco Solutions GmbH des Informatikers Torsten Schaub, der mit seinem KI-System Clingo komplexe Optimierungsprobleme in Betrieben löst. Oder von der SEQSTANT GmbH, die mit innovativer Diagnostik Erreger von Atemwegserkrankungen in Echtzeit bestimmen kann. Wir zeigen aber auch, wie Forschungsteams mit der Industrie kooperieren, zum Beispiel mit der K-UTEC im thüringischen Sondershausen, um mit wissenschaftlichem Knowhow dazu beizutragen, dass dort in Produktionsabfällen kein wertvolles Lithium verloren geht.
Richtet sich der Technologietransfer vor allem an die Wirtschaft, so hilft der Wissenstransfer der gesamten Gesellschaft. Besonders stark ist die Universität Potsdam hier in der Bildung, denn mit ihren Lehramtsabsolventen schickt sie auch gleich den aktuellen Stand der Unterrichtsforschung in die Schulpraxis. Immer häufiger zieht dabei die Digitalisierung in die Klassenzimmer ein. Wie das gut gelingen kann, ist in diesem Magazin zu lesen. Zudem erklären wir, was die Sportwissenschaft zur Therapie von Depressionen beitragen kann oder wie die Umweltforschung das Risikomanagement in von Hochwasser bedrohten Regionen verbessern will. Ob in öffentlichen Verwaltungen oder politischen Institutionen – überall ist wissenschaftliche Expertise gefragt. Wir zeigen das am Beispiel von Frauke Brosius-Gersdorf, die als Juristin die Bundesregierung zur Regulierung des Schwangerschaftsabbruchs berät.
Der kürzeste Weg des Wissens aus der Universität in die Praxis führt zweifelsohne über die Alumni, die als Fach- und Führungskräfte im Land und darüber hinaus wirksam werden. Dass dieser Weg schon während des Studiums beginnen kann, beweisen die vielen studentischen Initiativen, die hier zu Wort kommen. Sie alle scheuen nicht das Rampenlicht: ob bei Science Slams auf den Bühnen im Land Brandenburg, bei den TEDx-Talks im Hans Otto Theater, beim Kunst-Rundgang in der Potsdamer Waschhaus-Arena oder mit englischsprachigem Schauspiel an der Uni. Öffentlich in Erscheinung treten, neue Formen finden, um Wissen in die Breite der Bevölkerung zu tragen – auch das gehört zum Transfer. Genau wie dieses Magazin.
In many churches nowadays, there has been a standardized approach to premarital counseling for couples involving social, pastoral, and psychological perspectives. In contrast, many rabbis and other Jewish officials still concentrate on legal aspects alone. The need for resolving important issues on the verge of wedlock is too often left to secular experts in law, psychology, or counseling. However, in recent years, this lack of formal training for marriage preparation has also been acknowledged by the Jewish clergy in order to incorporate it in the preparatory period before the bond is tied. This case study focuses on Jewish and Roman Catholic conceptions of marriage, past and present. We intend to do a comparative analysis of the prerequisites of religious marriage based on the assumption that both Judaism and the Roman Catholic Church have a distinct legal framework to assess marriage preparation.
Long-term bacteria-fungi-plant associations in permafrost soils inferred from palaeometagenomics
(2024)
The arctic is warming 2 – 4 times faster than the global average, resulting in a strong feedback on northern ecosystems such as boreal forests, which cover a vast area of the high northern latitudes. With ongoing global warming, the treeline subsequently migrates northwards into tundra areas. The consequences of turning ecosystems are complex: on the one hand, boreal forests are storing large amounts of global terrestrial carbon and act as a carbon sink, dragging carbon dioxide out of the global carbon cycle, suggesting an enhanced carbon uptake with increased tree cover. On the other hand, with the establishment of trees, the albedo effect of tundra decreases, leading to enhanced soil warming. Meanwhile, permafrost thaws, releasing large amounts of previously stored carbon into the atmosphere. So far, mainly vegetation dynamics have been assessed when studying the impact of warming onto ecosystems. Most land plants are living in close symbiosis with bacterial and fungal communities, sustaining their growth in nutrient poor habitats. However, the impact of climate change on these subsoil communities alongside changing vegetation cover remains poorly understood. Therefore, a better understanding of soil community dynamics on multi millennial timescales is inevitable when addressing the development of entire ecosystems. Unravelling long-term cross-kingdom dependencies between plant, fungi, and bacteria is not only a milestone for the assessment of warming on boreal ecosystems. On top, it also is the basis for agriculture strategies to sustain society with sufficient food in a future warming world.
The first objective of this thesis was to assess ancient DNA as a proxy for reconstructing the soil microbiome (Manuscripts I, II, III, IV). Research findings across these projects enable a comprehensive new insight into the relationships of soil microorganisms to the surrounding vegetation. First, this was achieved by establishing (Manuscript I) and applying (Manuscript II) a primer pair for the selective amplification of ancient fungal DNA from lake sediment samples with the metabarcoding approach. To assess fungal and plant co-variation, the selected primer combination (ITS67, 5.8S) amplifying the ITS1 region was applied on samples from five boreal and arctic lakes. The obtained data showed that the establishment of fungal communities is impacted by warming as the functional ecological groups are shifting. Yeast and saprotroph dominance during the Late Glacial declined with warming, while the abundance of mycorrhizae and parasites increased with warming. The overall species richness was also alternating. The results were compared to shotgun sequencing data reconstructing fungi and bacteria (Manuscripts III, IV), yielding overall comparable results to the metabarcoding approach. Nonetheless, the comparison also pointed out a bias in the metabarcoding, potentially due to varying ITS lengths or copy numbers per genome.
The second objective was to trace fungus-plant interaction changes over time (Manuscripts II, III). To address this, metabarcoding targeting the ITS1 region for fungi and the chloroplast P6 loop for plants for the selective DNA amplification was applied (Manuscript II). Further, shotgun sequencing data was compared to the metabarcoding results (Manuscript III). Overall, the results between the metabarcoding and the shotgun approaches were comparable, though a bias in the metabarcoding was assumed. We demonstrated that fungal shifts were coinciding with changes in the vegetation. Yeast and lichen were mainly dominant during the Late Glacial with tundra vegetation, while warming in the Holocene lead to the expansion of boreal forests with increasing mycorrhizae and parasite abundance. Aside, we highlighted that Pinaceae establishment is dependent on mycorrhizal fungi such as Suillineae, Inocybaceae, or Hyaloscypha species also on long-term scales.
The third objective of the thesis was to assess soil community development on a temporal gradient (Manuscripts III, IV). Shotgun sequencing was applied on sediment samples from the northern Siberian lake Lama and the soil microbial community dynamics compared to ecosystem turnover. Alongside, podzolization processes from basaltic bedrock were recovered (Manuscript III). Additionally, the recovered soil microbiome was compared to shotgun data from granite and sandstone catchments (Manuscript IV, Appendix). We assessed if the establishment of the soil microbiome is dependent on the plant taxon and as such comparable between multiple geographic locations or if the community establishment is driven by abiotic soil properties and as such the bedrock area. We showed that the development of soil communities is to a great extent driven by the vegetation changes and temperature variation, while time only plays a minor role. The analyses showed general ecological similarities especially between the granite and basalt locations, while the microbiome on species-level was rather site-specific. A greater number of correlated soil taxa was detected for deep-rooting boreal taxa in comparison to grasses with shallower roots. Additionally, differences between herbaceous taxa of the late Glacial compared to taxa of the Holocene were revealed.
With this thesis, I demonstrate the necessity to investigate subsoil community dynamics on millennial time scales as it enables further understanding of long-term ecosystem as well as soil development processes and such plant establishment. Further, I trace long-term processes leading to podzolization which supports the development of applied carbon capture strategies under future global warming.
Does working in a gender-atypical occupation reduce individuals’ likelihood of finding a different-sex romantic partner, and do such occupational partnership penalties contribute to occupational gender segregation? To answer this question, we theorized partnership penalties for working in gender-atypical occupations by drawing on insights from evolutionary psychology, social constructivism, and rational choice theory and exploited the stability of occupational pathways in Germany. In Study 1, we analyzed observational data from a national probability sample (N= 1,634,944) to assess whether individuals in gender-atypical occupations were less likely to be partnered than individuals who worked in gender typical occupations. To assess whether the observed partnership gaps found in Study 1 were causally related to the gender typicality of men’s and women’s occupations, we conducted a field experiment on a dating app (N = 6,778). Because the findings from Study 2 suggested that young women and men indeed experienced penalties for working in a gender-atypical occupation (at least when they were not highly attractive), we employed a choice-experimental design in Study 3 (N = 1,250) to assess whether women and men were aware of occupational partnership penalties and showed that anticipating occupational partnership penalties may keep young and highly educated women from working in gender-atypical occupations. Our main conclusion therefore is that that observed penalties and their anticipation seem to be driven by unconscious rather than conscious processes.
Das Forschungsprojekt „Workflow-Management-Systeme für Open-Access-Hochschulverlage (OA-WFMS)” ist eine Kooperation zwischen der HTWK Leipzig und der Universität Potsdam. Ziel ist es, die Bedarfe von Universitäts- und Hochschulverlagen und Anforderungen an ein Workflow-Management-Systeme (WFMS) zu analysieren, um daraus ein generisches Lastenheft zu erstellen. Das WFMS soll den Publikationsprozess in OA-Verlagen erleichtern, beschleunigen sowie die Verbreitung von Open Access und das nachhaltige, digitale wissenschaftliche Publizieren fördern.
Das Projekt baut auf den Ergebnissen der Projekte „Open-Access-Hochschulverlag (OA-HVerlag)“ und „Open-Access-Strukturierte-Kommunikation (OA-STRUKTKOMM)“ auf. Der diesem Bericht zugrunde liegende Auftaktworkshop fand 2024 in Leipzig mit Vertreter:innen von zehn Institutionen statt. Der Workshop diente dazu, Herausforderungen und Anforderungen an ein WFMS zu ermitteln sowie bestehende Lösungsansätze und Tools zu diskutieren.
Im Workshop wurden folgende Fragen behandelt:
a. Wie kann die Organisation und Überwachung von Publikationsprozessen in wissenschaftlichen Verlagen durch ein WFMS effizient gestaltet werden?
b. Welche Anforderungen muss ein WFMS erfüllen, um Publikationsprozesse optimal zu unterstützen?
c. Welche Schnittstellen müssen berücksichtigt werden, um die Interoperabilität der Systeme zu garantieren?
d. Welche bestehenden Lösungsansätze und Tools sind bereits im Einsatz und welche Vor- und Nachteile haben diese?
Der Workshop gliederte sich in zwei Teile : Teil 1 behandelte Herausforderungen und Anforderungen (Fragen a. bis c.), Teil 2 bestehende Lösungen und Tools (Frage d.). Die Ergebnisse des Workshops fließen in die Bedarfsanalyse des Forschungsprojekts ein.
Die im Bericht dokumentierten Ergebnisse zeigen die Vielzahl der Herausforderungen der bestehenden Ansätze bezüglich des OA-Publikationsmanagements . Die Herausforderungen zeigen sich insbesondere bei der Systemheterogenität, den individuellen Anpassungsbedarfen und der Notwendigkeit der systematischen Dokumentation. Die eingesetzten Unterstützungssysteme und Tools wie Dateiablagen, Projektmanagement- und Kommunikationstools können insgesamt den Anforderungen nicht genügen, für Teillösungen sind sie jedoch nutzbar. Deshalb muss die Integration bestehender Systeme in ein zu entwickelndes OA-WFMS in Betracht gezogen und die Interoperabilität der miteinander interagierenden Systeme gewährleistet werden. Die Beteiligten des Workshops waren sich einig, dass das OA-WFMS flexibel und modular aufgebaut werden soll. Einer konsortialen Softwareentwicklung und einem gemeinsamen Betrieb im Verbund wurde der Vorrang gegeben.
Der Workshop lieferte wertvolle Einblicke in die Arbeit der Hochschulverlage und bildet somit eine solide Grundlage für die in Folge zu erarbeitende weitere Bedarfsanalyse und die Erstellung des generischen Lastenheftes.
Diskursive Perspektiven auf internationale Politik haben in den vergangenen Jahren an Relevanz und Popularität gewonnen. Der vorliegende Beitrag gibt zunächst einen Überblick über verschiedene Spielarten diskursiver Ansätze in den Internationalen Beziehungen, um sich dann vor allem poststrukturalistisch inspirierten Diskursarbeiten zu widmen. Poststrukturalistische Ansätze, so argumentieren wir, sind besonders interessant für die Disziplin der IB, da sie vier spezifische Gewinne bieten: Erstens erlauben sie eine kritische Perspektive auf Fragen internationaler Politik, zweitens hilft eine poststrukturalistische Perspektive dabei, den oft übersehenen politischen Charakter sozialer Realität herauszustellen, drittens halten sie dazu an, die eigene Sichtweise des/der Forschenden zu reflektieren und viertens erlaubt es eine poststrukturalistische Vorgehensweise mit ihrem Fokus auf „Wie-möglich-Fragen“, eine alternative analytische Perspektive zu dominanten erklärenden Ansätzen einzunehmen.
Cross-sectional associations of dietary biomarker patterns with health and nutritional status
(2024)
Der Data Act
(2024)
Der Data Act bildet den vorläufigen Schlussstein der EU-Datenregulierung. Die verschiedenen Instrumente der Verordnung tarieren vor allem die Beziehungen der Datenökonomie mit Datenzugangsrechten, weitreichenden Regelungen zu Datenverträgen und Cloud-Services sowie mit spezifischen Interoperabilitätsvorgaben neu aus. Der Beitrag gibt – mit einem Schwerpunkt im Datenwirtschaftsrecht – einen Überblick über die Neuregelungen, zeigt übergreifende Weichenstellungen auf und benennt strukturelle Herausforderungen.
Resolving the evolutionary history of two hippotragin antelopes using archival and ancient DNA
(2024)
African antelopes are iconic but surprisingly understudied in terms of their genetics, especially when it comes to their evolutionary history and genetic diversity. The age of genomics provides an opportunity to investigate evolution using whole nuclear genomes. Decreasing sequencing costs enable the recovery of multiple loci per genome, giving more power to single specimen analyses and providing higher resolution insights into species and populations that can help guide conservation efforts. This age of genomics has only recently begun for African antelopes. Many African bovids have a declining population trend and hence, are often endangered. Consequently, contemporary samples from the wild are often hard to collect. In these cases, ex situ samples from contemporary captive populations or in the form of archival or ancient DNA (aDNA) from historical museum or archaeological/paleontological specimens present a great research opportunity with the latter two even offering a window to information about the past. However, the recovery of aDNA is still considered challenging from regions with prevailing climatic conditions that are deemed adverse for DNA preservation like the African continent. This raises the question if DNA recovery from fossils as old as the early Holocene from these regions is possible.
This thesis focuses on investigating the evolutionary history and genetic diversity of two species: the addax (Addax nasomaculatus) and the blue antelope (Hippotragus leucophaeus). The addax is critically endangered and might even already be extinct in the wild, while the blue antelope became extinct ~1800 AD, becoming the first extinct large African mammal species in historical times. Together, the addax and the blue antelope can inform us about current and past extinction events and the knowledge gained can help guide conservation efforts of threatened species. The three studies used ex situ samples and present the first nuclear whole genome data for both species. The addax study used historical museum specimens and a contemporary sample from a captive population. The two studies on the blue antelope used mainly historical museum specimens but also fossils, and resulted in the recovery of the oldest paleogenome from Africa at that time.
The aim of the first study was to assess the genetic diversity and the evolutionary history of the addax. It found that the historical wild addax population showed only limited phylogeographic structuring, indicating that the addax was a highly mobile and panmictic population and suggesting that the current European captive population might be missing the majority of the historical mitochondrial diversity. It also found the nuclear and mitochondrial diversity in the addax to be rather low compared to other wild ungulate species. Suggestions on how to best save the remaining genetic diversity are presented. The European zoo population was shown to exhibit no or only minor levels of inbreeding, indicating good prospects for the restoration of the species in the wild. The trajectory of the addax’s effective population size indicated a major bottleneck in the late Pleistocene and a low effective population size well before recent human impact led to the species being critically endangered today.
The second study set out to investigate the identities of historical blue antelope specimens using aDNA techniques. Results showed that six out of ten investigated specimens were misidentified, demonstrating the blue antelope to be one of the scarcest mammal species in historical natural history collections, with almost no bone reference material. The preliminary analysis of the mitochondrial genomes suggested a low diversity and hence low population size at the time of the European colonization of southern Africa.
Study three presents the results of the analyses of two blue antelope nuclear genomes, one ~200 years old and another dating to the early Holocene, 9,800–9,300 cal years BP. A fossil-calibrated phylogeny dated the divergence time of the three historically extant Hippotragus species to ~2.86 Ma and demonstrated the blue and the sable antelope (H. niger) to be sister species. In addition, ancient gene flow from the roan (H. equinus) into the blue antelope was detected. A comparison with the roan and the sable antelope indicated that the blue antelope had a much lower nuclear diversity, suggesting a low population size since at least the early Holocene. This concurs with findings from the fossil record that show a considerable decline in abundance after the Pleistocene–Holocene transition. Moreover, it suggests that the blue antelope persisted throughout the Holocene regardless of a low population size, indicating that human impact in the colonial era was a major factor in the blue antelope’s extinction.
This thesis uses aDNA analyses to provide deeper insights into the evolutionary history and genetic diversity of the addax and the blue antelope. Human impact likely was the main driver of extinction in the blue antelope, and is likely the main factor threatening the addax today. This thesis demonstrates the value of ex situ samples for science and conservation, and suggests to include genetic data for conservation assessments of species. It further demonstrates the beneficial use of aDNA for the taxonomic identification of historically important specimens in natural history collections. Finally, the successful retrieval of a paleogenome from the early Holocene of Africa using shotgun sequencing shows that DNA retrieval from samples of that age is possible from regions generally deemed unfavorable for DNA preservation, opening up new research opportunities. All three studies enhance our knowledge of African antelopes, contributing to the general understanding of African large mammal evolution and to the conservation of these and similarly threatened species.
Die vorliegende Arbeit thematisiert die Synthese und die Polymerisation von Monomeren auf der Basis nachwachsender Rohstoffe wie zum Beispiel in Gewürzen und ätherischen Ölen enthaltenen kommerziell verfügbaren Phenylpropanoiden (Eugenol, Isoeugenol, Zimtalkohol, Anethol und Estragol) und des Terpenoids Myrtenol sowie ausgehend von der Rinde einer Birke (Betula pendula) und der Korkeiche (Quercus suber). Ausgewählte Phenylpropanoide (Eugenol, Isoeugenol und Zimtalkohol) und das Terpenoid Myrtenol wurden zunächst in den jeweiligen Laurylester überführt und anschließend das olefinische Strukturelement epoxidiert, wobei 4 neue (2-Methoxy-4-(oxiran-2-ylmethyl)phenyldodecanoat, 2-Methoxy-4-(3-methyl-oxiran-2-yl)phenyldodecanoat, (3-Phenyloxiran-2-yl)methyldodecanoat, (7,7-Dimethyl-3-oxatricyclo[4.1.1.02,4]octan-2-yl)methyldodecanoat) und 2 bereits bekannte monofunktionelle Epoxide (2-(4-Methoxybenzyl)oxiran und 2-(4-Methoxyphenyl)-3-methyloxiran) erhalten wurden, die mittels 1H-NMR-, 13C-NMR- und FT-IR-Spektroskopie sowie mit DSC untersucht wurden. Die Photo-DSC Untersuchung der Epoxidmonomere in einer kationischen Photopolymerisation bei 40 °C ergab die maximale Polymerisationsgeschwindigkeit (Rpmax: 0,005 s-1 bis 0,038 s-1) sowie die Zeit (tmax: 13 s bis 26 s) bis zum Erreichen des Rpmax-Wertes und führte zu flüssigen Oligomeren, deren zahlenmittlerer Polymerisationsgrad mit 3 bis 6 mittels GPC bestimmt wurde. Die Umsetzung von 2-Methoxy-4-(oxiran-2-ylmethyl)phenyldodecanoat mit Methacrylsäure ergab ein Isomerengemisch (2-Methoxy-4-(2-hydroxy-3-(methacryloyloxy)propyl)phenyldodecanoat und 2-Methoxy-4-(2-(methacryl-oyloxy)-3-hydroxypropyl)phenyldodecanoat), das mittels Photo-DSC in einer freien radikalischen Photopolymerisation untersucht wurde (Rpmax: 0,105 s-1 und tmax: 5 s), die zu festen in Chloroform unlöslichen Polymeren führte.
Aus Korkpulver und gemahlener Birkenrinde wurden selektiv 2 kristalline ω-Hydroxyfettsäuren (9,10-Epoxy-18-hydroxyoctadecansäure und 22-Hydroxydocosansäure) isoliert. Die kationische Photopolymerisation der 9,10-Epoxy-18-hydroxyoctadecansäure ergab einen nahezu farblosen transparenten und bei Raumtemperatur elastischen Film, welcher ein Anwendungspotential für Oberflächenbeschichtungen hat. Aus der Reaktion von 9,10-Epoxy-18-hydroxyoctadecansäure mit Methacrylsäure wurde ein bei Raumtemperatur flüssiges Gemisch aus zwei Konstitutionsisomeren (9,18-Dihydroxy-10-(methacryloyloxy)octadecansäure und 9-(Methacryloyloxy)-10,18-dihydroxyoctadecansäure) erhalten (Tg: -60 °C). Die radikalische Photopolymerisation dieser Konstitutionsisomere wurde ebenfalls mittels Photo-DSC untersucht (Rpmax: 0,098 s-1 und tmax: 3,8 s). Die Reaktion von 22-Hydroxydocosansäure mit Methacryloylchlorid ergab die kristalline 22-(Methacryloyloxy)docosansäure, welche ebenfalls in einer radikalischen Photopolymerisation mittels Photo-DSC untersucht wurde (Rpmax: 0,023 s-1 und tmax: 9,6 s).
Die mittels AIBN in Dimethylsulfoxid initiierte Homopolymerisation der 22-(Methacryloyloxy)docosansäure und der Isomerengemische bestehend aus 2-Methoxy-4-(2-hydroxy-3-(methacryloyloxy)propyl)phenyldodecanoat und 2-Methoxy-4-(2-(methacryl-oyloxy)-3-hydroxypropyl)phenyldodecanoat sowie aus 9,18-Dihydroxy-10-(methacryloy-loxy)octadecansäure und 9-(Methacryloyloxy)-10,18-dihydroxyoctadecansäure ergab feste lösliche Polymere, die mittels 1H-NMR- und FT-IR-Spektroskopie, GPC (Poly(2-methoxy-4-(2-hydroxy-3-(methacryloyloxy)propyl)phenyldodecanoat / 2-methoxy-4-(2-(methacryloyloxy)-3-hydroxypropyl)phenyldodecanoat): Pn = 94) und DSC (Poly(2-methoxy-4-(2-hydroxy-3-(methacryloyloxy)propyl)phenyldodecanoat / 2-methoxy-4-(2-(methacryloyloxy)-3-hydroxypropyl)phenyldodecanoat): Tg: 52 °C; Poly(9,18-dihydroxy-10-(methacryloyloxy)-octadecansäure / 9-(methacryloyloxy)-10,18-dihydroxyoctadecansäure): Tg: 10 °C; Poly(22-(methacryloyloxy)docosansäure): Tm: 74,1 °C, wobei der Schmelzpunkt mit dem des Photopolymers (Tm = 76,8 °C) vergleichbar ist) charakterisiert wurden.
Das bereits bekannte Monomer 4-(4-Methacryloyloxyphenyl)butan-2-on wurde ausgehend von 4-(4-Hydroxyphenyl)butan-2-on hergestellt, welches aus Birkenrinde gewonnen werden kann, und unter identischen Bedingungen für einen Vergleich mit den neuen Monomeren polymerisiert. Die freie radikalische Polymerisation führte zu Poly(4-(4-methacryloyloxyphenyl)butan-2-on) (Pn: 214 und Tg: 83 °C). Neben der Homopolymerisation wurde eine statistische Copolymerisation des Isomerengemisches 2-Methoxy-4-(2-hydroxy-3-(methacryl-oyloxy)propyl)phenyldodecanoat / 2-Methoxy-4-(2-(methacryloyloxy)-3-hydroxypropyl)-phenyldodecanoat mit 4-(4-Methacryloyloxyphenyl)butan-2-on untersucht, wobei ein äquimolarer Einsatz der Ausgangsmonomere zu einem Anstieg der Ausbeute, der Molmassenverteilung und der Dispersität des Copolymers (Tg: 44 °C) führte. Die unter Verwendung von Diethylcarbonat als „grünes“ Lösungsmittel mittels AIBN initiierten freien radikalischen Homopolymerisationen von 4-(4-Methacryloyloxyphenyl)butan-2-on und von Laurylmethacrylat ergaben vergleichbare Polymerisationsgrade der Homopolymere (Pn: 150), welche jedoch aufgrund ihrer Strukturunterschiede deutlich unterschiedliche Glasübergangstemperaturen hatten (Poly(4-(4-methacryloyloxyphenyl)butan-2-on): Tg: 70 °C, Poly(laurylmethacrylat) Tg: -49 °C. Eine statistische Copolymerisation äquimolarer Stoffmengen der beiden Monomere in Diethylcarbonat führte bei einer Polymerisationszeit von 60 Minuten zu einem leicht bevorzugten Einbau des 4-(4-Methacryloyloxyphenyl)butan-2-on in das Copolymer (Tg: 17 °C). Copolymerisationsdiagramme für die freien radikalischen Copolymerisationen von 4-(4-Methacryloyloxyphenyl)butan-2-on mit n-Butylmethacrylat beziehungsweise 2-(Dimethylamino)ethylmethacrylat (t: 20 min bis 60 min; Molenbrüche (X) für 4-(4-Methacryloyloxyphenyl)butan-2-on: 0,2; 0,4; 0,6 und 0,8) zeigten ein nahezu ideales azeotropes Copolymerisationsverhalten, obwohl ein leicht bevorzugter Einbau von 4-(4-Methacryloyloxyphenyl)butan-2-on in das jeweilige Copolymer beobachtet wurde. Dabei korreliert ein Anstieg der Ausbeute und der Glasübergangstemperatur der erhaltenen Copolymere mit einem zunehmenden Gehalt an 4-(4-Methacryloyloxyphenyl)butan-2-on im Reaktionsgemisch. Die unter Einsatz der modifizierten Gibbs-DiMarzio-Gleichung berechneten Glasübergangstemperaturen der Copolymere stimmten mit den gemessenen Werten gut überein. Das ist eine gute Ausgangsbasis für die Bestimmung der Glasübergangstemperatur eines Copolymers mit einer beliebigen Zusammensetzung.
Sigmund Freud, the founder of psychoanalysis, began his intellectual life with the Jewish Bible and also ended it with it. He began by reading the Philippson Bible together, especially with his father Jacob Freud, and ended by studying the figure of Moses. This study systematically traces this preoccupation and shows that the Jewish Bible was a constant reference for Freud and determined his Jewish identity. This is shown by analysing family documents, religious instruction and references to the Bible in Freud's writings and correspondence.
Plate tectonic boundaries constitute the suture zones between tectonic plates. They are shaped by a variety of distinct and interrelated processes and play a key role in geohazards and georesource formation. Many of these processes have been previously studied, while many others remain unaddressed or undiscovered. In this work, the geodynamic numerical modeling software ASPECT is applied to shed light on further process interactions at continental plate boundaries. In contrast to natural data, geodynamic modeling has the advantage that processes can be directly quantified and that all parameters can be analyzed over the entire evolution of a structure. Furthermore, processes and interactions can be singled out from complex settings because the modeler has full control over all of the parameters involved. To account for the simplifying character of models in general, I have chosen to study generic geological settings with a focus on the processes and interactions rather than precisely reconstructing a specific region of the Earth.
In Chapter 2, 2D models of continental rifts with different crustal thicknesses between 20 and 50 km and extension velocities in the range of 0.5-10 mm/yr are used to obtain a speed limit for the thermal steady-state assumption, commonly employed to address the temperature fields of continental rifts worldwide. Because the tectonic deformation from ongoing rifting outpaces heat conduction, the temperature field is not in equilibrium, but is characterized by a transient, tectonically-induced heat flow signal. As a result, I find that isotherm depths of the geodynamic evolution models are shallower than a temperature distribution in equilibrium would suggest. This is particularly important for deep isotherms and narrow rifts. In narrow rifts, the magnitude of the transient temperature signal limits a well-founded applicability of the thermal steady-state assumption to extension velocities of 0.5-2 mm/yr. Estimation of the crustal temperature field affects conclusions on all temperature-dependent processes ranging from mineral assemblages to the feasible exploitation of a geothermal reservoir.
In Chapter 3, I model the interactions of different rheologies with the kinematics of folding and faulting using the example of fault-propagation folds in the Andean fold-and-thrust belt. The evolution of the velocity fields from geodynamic models are compared with those from trishear models of the same structure. While the latter use only geometric and kinematic constraints of the main fault, the geodynamic models capture viscous, plastic, and elastic deformation in the entire model domain. I find that both models work equally well for early, and thus relatively simple stages of folding and faulting, while results differ for more complex situations where off-fault deformation and secondary faulting are present. As fault-propagation folds can play an important role in the formation of reservoirs, knowledge of fluid pathways, for example via fractures and faults, is crucial for their characterization.
Chapter 4 deals with a bending transform fault and the interconnections between tectonics and surface processes. In particular, the tectonic evolution of the Dead Sea Fault is addressed where a releasing bend forms the Dead Sea pull-apart basin, while a restraining bend further to the North resulted in the formation of the Lebanese mountains. I ran 3D coupled geodynamic and surface evolution models that included both types of bends in a single setup. I tested various randomized initial strain distributions, showing that basin asymmetry is a consequence of strain localization. Furthermore, by varying the surface process efficiency, I find that the deposition of sediment in the pull-apart basin not only controls basin depth, but also results in a crustal flow component that increases uplift at the restraining bend.
Finally, in Chapter 5, I present the computational basis for adding further complexity to plate boundary models in ASPECT with the implementation of earthquake-like behavior using the rate-and-state friction framework. Despite earthquakes happening on a relatively small time scale, there are many interactions between the seismic cycle and the long time spans of other geodynamic processes. Amongst others, the crustal state of stress as well as the presence of fluids or changes in temperature may alter the frictional behavior of a fault segment. My work provides the basis for a realistic setup of involved structures and processes, which is therefore important to obtain a meaningful estimate for earthquake hazards.
While these findings improve our understanding of continental plate boundaries, further development of geodynamic software may help to reveal even more processes and interactions in the future.
The automotive industry is a prime example of digital technologies reshaping mobility. Connected, autonomous, shared, and electric (CASE) trends lead to new emerging players that threaten existing industrial-aged companies. To respond, incumbents need to bridge the gap between contrasting product architecture and organizational principles in the physical and digital realms. Over-the-air (OTA) technology, that enables seamless software updates and on-demand feature additions for customers, is an example of CASE-driven digital product innovation. Through an extensive longitudinal case study of an OTA initiative by an industrial- aged automaker, this dissertation explores how incumbents accomplish digital product innovation. Building on modularity, liminality, and the mirroring hypothesis, it presents a process model that explains the triggers, mechanisms, and outcomes of this process. In contrast to the literature, the findings emphasize the primacy of addressing product architecture challenges over organizational ones and highlight the managerial implications for success.
Assessing the impact of global change on hydrological systems is one of the greatest hydrological challenges of our time. Changes in land cover, land use, and climate have an impact on water quantity, quality, and temporal availability. There is a widespread consensus that, given the far-reaching effects of global change, hydrological systems can no longer be viewed as static in their structure; instead, they must be regarded as entire ecosystems, wherein hydrological processes interact and coevolve with biological, geomorphological, and pedological processes. To accurately predict the hydrological response under the impact of global change, it is essential to understand this complex coevolution. The knowledge of how hydrological processes, in particular the formation of subsurface (preferential) flow paths, evolve within this coevolution and how they feed back to the other processes is still very limited due to a lack of observational data.
At the hillslope scale, this intertwined system of interactions is known as the hillslope feedback cycle. This thesis aims to enhance our understanding of the hillslope feedback cycle by studying the coevolution of hillslope structure and hillslope hydrological response. Using chronosequences of moraines in two glacial forefields developed from siliceous and calcareous glacial till, the four studies shed light on the complex coevolution of hydrological, biological, and structural hillslope properties, as well as subsurface hydrological flow paths over an evolutionary period of 10 millennia in these two contrasting geologies. The findings indicate that the contrasting properties of siliceous and calcareous parent materials lead
to variations in soil structure, permeability, and water storage. As a result, different plant species and vegetation types are favored on siliceous versus calcareous parent material, leading to diverse ecosystems with distinct hydrological dynamics. The siliceous parent material was found to show a higher activity level in driving the coevolution. The soil pH resulting from parent material weathering emerges as a crucial factor, influencing vegetation development, soil formation, and consequently, hydrology. The acidic weathering of the siliceous parent material favored the accumulation of organic matter, increasing the soils’ water storage capacity and attracting acid-loving shrubs, which further promoted organic matter accumulation and ultimately led to podsolization after 10 000 years. Tracer experiments revealed that the subsurface flow path evolution was influenced by soil and vegetation development, and vice versa. Subsurface flow paths changed from vertical, heterogeneous matrix flow to finger-like flow paths over a few hundred years, evolving into macropore flow, water storage, and lateral subsurface flow after several thousand years. The changes in flow paths among younger age classes were driven by weathering processes altering soil structure, as well as by vegetation development and root activity. In the older age
class, the transition to more water storage and lateral flow was attributed to substantial organic matter accumulation and ongoing podsolization. The rapid vertical water transport in the finger-like flow paths, along with the conductive sandy material, contributed to podsolization and thus to the shift in the hillslope hydrological response.
In contrast, the calcareous site possesses a high pH buffering capacity, creating a neutral to basic environment with relatively low accumulation of dead organic matter, resulting in a lower water storage capacity and the establishment of predominantly grass vegetation. The coevolution was found to be less dynamic over the millennia. Similar to the siliceous site, significant changes in subsurface flow paths occurred between the young age classes. However, unlike the siliceous site, the subsurface flow paths at the calcareous site only altered in shape and not in direction. Tracer experiments showed that flow paths changed from vertical, heterogeneous matrix flow to vertical, finger-like flow paths after a few hundred to thousands of years, which was driven by root activities and weathering processes. Despite having a finer soil texture, water storage at the calcareous site was significantly lower than at the siliceous site, and water transport remained primarily rapid and vertical, contributing to the flourishing of grass vegetation.
The studies elucidated that changes in flow paths are predominantly shaped by the characteristics of the parent material and its weathering products, along with their complex interactions with initial water flow paths and vegetation development. Time, on the other hand, was not found to be a primary factor in describing the evolution of the hydrological response. This thesis makes a valuable contribution to closing the gap in the observations of the coevolution of hydrological processes within the hillslope feedback cycle, which is important to improve predictions of hydrological processes in changing landscapes. Furthermore, it emphasizes the importance of interdisciplinary studies in addressing the hydrological challenges arising from global change.
Protected cultivation in greenhouses or polytunnels offers the potential for sustainable production of high-yield, high-quality vegetables. This is related to the ability to produce more on less land and to use resources responsibly and efficiently. Crop yield has long been considered the most important factor. However, as plant-based diets have been proposed for a sustainable food system, the targeted enrichment of health-promoting plant secondary metabolites should be addressed. These metabolites include carotenoids and flavonoids, which are associated with several health benefits, such as cardiovascular health and cancer protection.
Cover materials generally have an influence on the climatic conditions, which in turn can affect the levels of secondary metabolites in vegetables grown underneath. Plastic materials are cost-effective and their properties can be modified by incorporating additives, making them the first choice. However, these additives can migrate and leach from the material, resulting in reduced service life, increased waste and possible environmental release. Antifogging additives are used in agricultural films to prevent the formation of droplets on the film surface, thereby increasing light transmission and preventing microbiological contamination.
This thesis focuses on LDPE/EVA covers and incorporated antifogging additives for sustainable protected cultivation, following two different approaches. The first addressed the direct effects of leached antifogging additives using simulation studies on lettuce leaves (Lactuca sativa var capitata L). The second determined the effect of antifog polytunnel covers on lettuce quality. Lettuce is usually grown under protective cover and can provide high nutritional value due to its carotenoid and flavonoid content, depending on the cultivar.
To study the influence of simulated leached antifogging additives on lettuce leaves, a GC-MS method was first developed to analyze these additives based on their fatty acid moieties. Three structurally different antifogging additives (reference material) were characterized outside of a polymer matrix for the first time. All of them contained more than the main fatty acid specified by the manufacturer. Furthermore, they were found to adhere to the leaf surface and could not be removed by water or partially by hexane.
The incorporation of these additives into polytunnel covers affects carotenoid levels in lettuce, but not flavonoids, caffeic acid derivatives and chlorophylls. Specifically, carotenoids were higher in lettuce grown under polytunnels without antifog than with antifog. This has been linked to their effect on the light regime and was suggested to be related to carotenoid function in photosynthesis.
In terms of protected cultivation, the use of LDPE/EVA polytunnels affected light and temperature, and both are closely related. The carotenoid and flavonoid contents of lettuce grown under polytunnels was reversed, with higher carotenoid and lower flavonoid levels. At the individual level, the flavonoids detected in lettuce did not differ however, lettuce carotenoids adapted specifically depending on the time of cultivation. Flavonoid reduction was shown to be transcriptionally regulated (CHS) in response to UV light (UVR8). In contrast, carotenoids are thought to be regulated post-transcriptionally, as indicated by the lack of correlation between carotenoid levels and transcripts of the first enzyme in carotenoid biosynthesis (PSY) and a carotenoid degrading enzyme (CCD4), as well as the increased carotenoid metabolic flux. Understanding the regulatory mechanisms and metabolite adaptation strategies could further advance the strategic development and selection of cover materials.
Microalgae have been recognized as a promising green production platform for recombinant proteins. The majority of studies on recombinant protein expression have been conducted in the green microalga C. reinhardtii. While promising improvement regarding nuclear transgene expression in this alga has been made, it is still inefficient due to epigenetic silencing, often resulting in low yields that are not competitive with other expressor organisms. Other microalgal species might be better suited for high-level protein expression, but are limited in their availability of molecular tools.
The red microalga Porphyridium purpureum recently emerged as candidate for the production of recombinant proteins. It is promising in that transformation vectors are episomally maintained as autonomously replicating plasmids in the nucleus at a high copy number, thus leading to high expression values in this red alga.
In this work, we expand the genetic tools for P. purpureum and investigate parameters that govern efficient transgene expression. We provide an improved transformation protocol to streamline the generation of transgenic lines in this organism. After being able to efficiently generate transgenic lines, we showed that codon usage is a main determinant of high-level transgene expression, not only at the protein level but also at the level of mRNA accumulation. The optimized expression constructs resulted in YFP accumulation up to an unprecedented 5% of the total soluble protein. Furthermore, we designed new constructs conferring efficient transgene expression into the culture medium, simplifying purification and harvests of recombinant proteins. To further improve transgene expression, we tested endogenous promoters driving the most highly transcribed genes in P. purpureum and found minor increase of YFP accumulation.
We employed the previous findings to express complex viral antigens from the hepatitis B virus and the hepatitis C virus in P. purpureum to demonstrate its feasibility as producer of biopharmaceuticals. The viral glycoproteins were successfully produced to high levels and could reach their native confirmation, indicating a functional glycosylation machinery and an appropriate folding environment in this red alga. We could successfully upscale the biomass production of transgenic lines and with that provide enough material for immunization trials in mice that were performed in collaboration. These trials showed no toxicity of neither the biomass nor the purified antigens, and, additionally, the algal-produced antigens were able to elicit a strong and specific immune response.
The results presented in this work pave the way for P. purpureum as a new promising producer organism for biopharmaceuticals in the microalgal field.
Column-oriented database systems can efficiently process transactional and analytical queries on a single node. However, increasing or peak analytical loads can quickly saturate single-node database systems. Then, a common scale-out option is using a database cluster with a single primary node for transaction processing and read-only replicas. Using (the naive) full replication, queries are distributed among nodes independently of the accessed data. This approach is relatively expensive because all nodes must store all data and apply all data modifications caused by inserts, deletes, or updates.
In contrast to full replication, partial replication is a more cost-efficient implementation: Instead of duplicating all data to all replica nodes, partial replicas store only a subset of the data while being able to process a large workload share. Besides lower storage costs, partial replicas enable (i) better scaling because replicas must potentially synchronize only subsets of the data modifications and thus have more capacity for read-only queries and (ii) better elasticity because replicas have to load less data and can be set up faster. However, splitting the overall workload evenly among the replica nodes while optimizing the data allocation is a challenging assignment problem.
The calculation of optimized data allocations in a partially replicated database cluster can be modeled using integer linear programming (ILP). ILP is a common approach for solving assignment problems, also in the context of database systems. Because ILP is not scalable, existing approaches (also for calculating partial allocations) often fall back to simple (e.g., greedy) heuristics for larger problem instances. Simple heuristics may work well but can lose optimization potential.
In this thesis, we present optimal and ILP-based heuristic programming models for calculating data fragment allocations for partially replicated database clusters. Using ILP, we are flexible to extend our models to (i) consider data modifications and reallocations and (ii) increase the robustness of allocations to compensate for node failures and workload uncertainty. We evaluate our approaches for TPC-H, TPC-DS, and a real-world accounting workload and compare the results to state-of-the-art allocation approaches. Our evaluations show significant improvements for varied allocation’s properties: Compared to existing approaches, we can, for example, (i) almost halve the amount of allocated data, (ii) improve the throughput in case of node failures and workload uncertainty while using even less memory, (iii) halve the costs of data modifications, and (iv) reallocate less than 90% of data when adding a node to the cluster. Importantly, we can calculate the corresponding ILP-based heuristic solutions within a few seconds. Finally, we demonstrate that the ideas of our ILP-based heuristics are also applicable to the index selection problem.
Im Rahmen einer explorativen Entwicklung wurde in der vorliegenden Studie ein Konzept zur Wissenschaftskommunikation für ein Graduiertenkolleg, in dem an photochemischen Prozessen geforscht wird, erstellt und anschließend evaluiert. Der Grund dafür ist die immer stärker wachsende Forderung nach Wissenschaftskommunikation seitens der Politik. Es wird darüber hinaus gefordert, dass die Kommunikation der eigenen Forschung in Zukunft integrativer Bestandteil des wissenschaftlichen Arbeitens wird. Um junge Wissenschaftler bereits frühzeitig auf diese Aufgabe vorzubereiten, wird Wissenschaftskommunikation auch in Forschungsverbünden realisiert.
Aus diesem Grund wurde in einer Vorstudie untersucht, welche Anforderungen an ein Konzept zur Wissenschaftskommunikation im Rahmen eines Forschungsverbundes gestellt werden, indem die Einstellung der Doktoranden zur Wissenschaftskommunikation sowie ihre Kommunikationsfähigkeiten anhand eines geschlossenen Fragebogens evaluiert wurden. Darüber hinaus wurden aus den Daten Wissenschaftskommunikationstypen abgeleitet. Auf Grundlage der Ergebnisse wurden unterschiedliche Wissenschaftskommunikationsmaßnahmen entwickelt, die sich in der Konzeption, den Rezipienten, sowie der Form der Kommunikation und den Inhalten unterscheiden.
Im Rahmen dieser Entwicklung wurde eine Lerneinheit mit Bezug auf die Inhalte des Graduiertenkollegs, bestehend aus einem Lehr-Lern-Experiment und den dazugehörigen Begleitmaterialien, konzipiert. Anschließend wurde die Lerneinheit in eine der Wissenschaftskommunikationsmaßnahmen integriert. Je nach Anforderung an die Doktoranden, wurden die Maßnahmen durch vorbereitende Workshops ergänzt.
Durch einen halboffenen Pre-Post-Fragebogen wurde der Einfluss der Wissenschaftskommunikationsmaßnahmen und der dazugehörigen Workshops auf die Selbstwirksamkeit der Doktoranden evaluiert, um Rückschlüsse darauf zu ziehen, wie sich die Wahrnehmung der eigenen Kommunikationsfähigkeiten durch die Interventionen verändert. Die Ergebnisse deuten darauf hin, dass die einzelnen Wissenschaftskommunikationsmaßnahmen die verschiedenen Typen in unterschiedlicher Weise beeinflussen. Es ist anzunehmen, dass es abhängig von der eigenen Einschätzung der Kommunikationsfähigkeit unterschiedliche Bedürfnisse der Förderung gibt, die durch dedizierte Wissenschaftskommunikationsmaßnahmen berücksichtigt werden können.
Auf dieser Grundlage werden erste Ansätze für eine allgemeingültige Strategie vorgeschlagen, die die individuellen Fähigkeiten zur Wissenschaftskommunikation in einem naturwissenschaftlichen Forschungsverbund fördert.
This thesis focuses on the molecular evolution of Macroscelidea, commonly referred to as sengis. Sengis are a mammalian order belonging to the Afrotherians, one of the four major clades of placental mammals. Sengis currently consist of twenty extant species, all of which are endemic to the African continent. They can be separated in two families, the soft-furred sengis (Macroscelididae) and the giant sengis (Rhynchocyonidae). While giant sengis can be exclusively found in forest habitats, the different soft-furred sengi species dwell in a broad range of habitats, from tropical rain-forests to rocky deserts.
Our knowledge on the evolutionary history of sengis is largely incomplete. The high level of superficial morphological resemblance among different sengi species (especially the soft-furred sengis) has for example led to misinterpretations of phylogenetic relationships, based on morphological characters. With the rise of DNA based taxonomic inferences, multiple new genera were defined and new species described. Yet, no full taxon molecular phylogeny exists, hampering the answering of basic taxonomic questions. This lack of knowledge can be to some extent attributed to the limited availability of fresh-tissue samples for DNA extraction. The broad African distribution, partly in political unstable regions and low population densities complicate contemporary sampling approaches. Furthermore, the DNA information available usually covers only short stretches of the mitochondrial genome and thus a single genetic locus with limited informational content.
Developments in DNA extraction and library protocols nowadays offer the opportunity to access DNA from museum specimens, collected over the past centuries and stored in natural history museums throughout the world. Thus, the difficulties in fresh-sample acquisition for molecular biological studies can be overcome by the application of museomics, the research field which emerged from those laboratory developments.
This thesis uses fresh-tissue samples as well as a vast collection museum specimens to investigate multiple aspects about the macroscelidean evolutionary history. Chapter 4 of this thesis focuses on the phylogenetic relationships of all currently known sengi species. By accessing DNA information from museum specimens in combination of fresh tissue samples and publicly available genetic resources it produces the first full taxon molecular phylogeny of sengis. It confirms the monophyly of the genus Elephantulus and discovers multiple deeply divergent lineages within different species, highlighting the need for species specific approaches. The study furthermore focuses on the evolutionary time frame of sengis by evaluating the impact of commonly varied parameters on tree dating. The results of the study show, that the mitochondrial information used in previous studies to temporal calibrate the Macroscelidean phylogeny led to an overestimation of node ages within sengis. Especially soft-furred sengis are thus much younger than previously assumed. The refined knowledge of nodes ages within sengis offer the opportunity to link e.g. speciation events to environmental changes.
Chapter 5 focuses on the genus Petrodromus with its single representative Petrodromus tetradactylus. It again exploits the opportunities of museomics and gathers a comprehensive, multi-locus genetic dataset of P. tetradactylus individuals, distributed across most the known range of this species. It reveals multiple deeply divergent lineages within Petrodromus, whereby some could possibly be associated to previously described sub-species, at least one was formerly unknown. It underscores the necessity for a revision of the genus Petrodromus through the integration of both molecular and morphological evidence. The study, furthermore identifies changing forest distributions through climatic oscillations as main factor shaping the genetic structure of Petrodromus.
Chapter 6 uses fresh tissue samples to extent the genomic resources of sengis by thirteen new nuclear genomes, of which two were de-novo assembled. An extensive dataset of more than 8000 protein coding one-to-one orthologs allows to further refine and confirm the temporal time frame of sengi evolution found in Chapter 4. This study moreover investigates the role of gene-flow and incomplete lineage sorting (ILS) in sengi evolution. In addition it identifies clade specific genes of possible outstanding evolutionary importance and links them to potential phenotypic traits affected. A closer investigation of olfactory receptor proteins reveals clade specific differences. A comparison of the demographic past of sengis to other small African mammals does not reveal a sengi specific pattern.
Kochbücher à la religion
(2024)
Zur Auswertung der Umfrage
(2024)
Religionen sind wichtige Akteurinnen der Zivilgesellschaft. Die Frage, wie sie miteinander umgehen, ist von entscheidender Bedeutung für die Zukunft pluraler, offener Gesellschaften. Für dieses Buch haben sich vier Akteure der interreligiösen Verständigung erstmals zusammengetan: Die national und international agierenden Organisationen Religions for Peace und Stiftung Weltethos, der Bundeskongress der Räte der Religionen als Verbund kommunaler interreligiöser Initiativen sowie die Forschungsschnittstelle Forum Religionen im Kontext an der Universität Potsdam. Das Buch enthält Steckbriefe von siebzig interreligiösen Organisationen und Initiativen. Ergänzt wird es durch Reflexionen über die Geschichte und die Zukunft des interreligiösen Dialogs in Deutschland sowie über die Rolle von Religion in der Zivilgesellschaft.
Der Föderalismus, dessen Wurzeln bis in das Mittelalter zurückreichen, gehört zu den Grundtatsachen der deutschen Geschichte. Dieses historische Erbe spiegelt sich in der heutigen deutschen Staatlichkeit wider, wie sie im Grundgesetz verankert ist und von Bund, Ländern und Kommunen mit Leben erfüllt wird. Renommierte Historiker, Politologen und Rechtswissenschaftler zeichnen in diesem Band die grundlegenden Entwicklungen der Föderalismusgeschichte in Deutschland seit der Gründung des deutschen Nationalstaats (1871) nach. Sie zeigen dabei die Kontinuitäten und Systembrüche deutscher Staatlichkeit auf – vom Kaiserreich über die Weimarer Republik und den NS-Staat bis hin zur Gegenwart in der Bundesrepublik Deutschland.
Zum Werk
Der Band zum Eigentümer-Besitzer-Verhältnis erscheint nunmehr in 10. Auflage und behandelt in bewährter Darstellungsform die wichtigsten in den Übungen und im Examen zur Bearbeitung gestellten Streitfragen aus diesem Bereich des Sachenrechts.
Die einzelnen Probleme werden anhand von Beispielfällen erklärt, die in Lehre und Rechtsprechung vertretenen Meinungen werden einander dabei gegenübergestellt, die sie tragenden Argumente werden in Kürze herausgearbeitet und an weiteren Fällen erprobt. Auf diese Weise entwickeln Studierende das für die Falllösung relevante juristische Problembewusstsein sowie die Fähigkeit, die verschiedenen Ansichten und Argumente gegeneinander abzuwägen, eine eigene Meinung zu bilden und sie überzeugend zu begründen.
Vorteile auf einen Blick alle relevanten Probleme zum Eigentümer-Besitzer-Verhältnis in einem Band umfassende Fundstellensammlung für die in Lehre und Rechtsprechung vertretenen Meinungen
Zur Neuauflage
Für die Neuauflage wurden die aktuelle Literatur sowie die neueste Rechtsprechung eingearbeitet sowie ein Abschnitt zum Aufbau von Meinungsstreits in Prüfungen ergänzt.
Zielgruppe
Für Studierende der Rechtswissenschaften, Rechtsreferendarinnen und -referendare und AG-Leiterinnen und -Leiter.
Jahresbericht 2023
(2024)
Dieser Jahresbericht umfasst den Berichtszeitraum 2023, in dem Forschung und Lehre wieder in Präsenz stattfinden konnten. Begegnung und Austausch in Hörsaal und Seminarraum, auf Konferenzpaneln und während Kaffeepausen sind wieder möglich, aber die Möglichkeiten von Homeoffice und Onlinekommunikation bleiben weiter bestehen, wie die Erfahrung zeigt.
Das MenschenRechtsZentrum als interdisziplinär arbeitende, zentrale wissenschaftliche Einrichtung der Universität Potsdam hat es im Berichtszeitraum erneut unternommen, juristische, philosophische, geschichts- und kultur- sowie politikwissenschaftliche Perspektiven auf das Thema Menschenrechte in Forschung und Lehre miteinander zu verbinden.
Die Wissenschaftler*innen des MenschenRechtsZentrums lehren an den Fakultäten, denen sie angehören. Hier werden daher nur diejenigen Aktivitäten angeführt, die einen Bezug zur Arbeit des MenschenRechtsZentrums sowie zu menschenrechtlichen Fragestellungen haben; weitergehende Informationen finden sich auf den Homepages der jeweiligen Personen.
Purpose
With shorter product cycles and a growing number of knowledge-intensive business processes, time consumption is a highly relevant target factor in measuring the performance of contemporary business processes. This research aims to extend prior research on the effects of knowledge transfer velocity at the individual level by considering the effect of complexity, stickiness, competencies, and further demographic factors on knowledge-intensive business processes at the conversion-specific levels.
Design/methodology/approach
We empirically assess the impact of situation-dependent knowledge transfer velocities on time consumption in teams and individuals. Further, we issue the demographic effect on this relationship. We study a sample of 178 experiments of project teams and individuals applying ordinary least squares (OLS) for regression analysis-based modeling.
Findings
The authors find that time consumed at knowledge transfers is negatively associated with the complexity of tasks. Moreover, competence among team members has a complementary effect on this relationship and stickiness retards knowledge transfers. Thus, while demographic factors urgently need to be considered for effective and speedy knowledge transfers, these influencing factors should be addressed on a conversion-specific basis so that some tasks are realized in teams best while others are not. Guidelines and interventions are derived to identify best task realization variants, so that process performance is improved by a new kind of process improvement method.
Research limitations/implications
This study establishes empirically the importance of conversion-specific influence factors and demographic factors as drivers of high knowledge transfer velocities in teams and among individuals. The contribution connects the field of knowledge management to important streams in the wider business literature: process improvement, management of knowledge resources, design of information systems, etc. Whereas the model is highly bound to the experiment tasks, it has high explanatory power and high generalizability to other contexts.
Practical implications
Team managers should take care to allow the optimal knowledge transfer situation within the team. This is particularly important when knowledge sharing is central, e.g. in product development and consulting processes. If this is not possible, interventions should be applied to the individual knowledge transfer situation to improve knowledge transfers among team members.
Social implications
Faster and more effective knowledge transfers improve the performance of both commercial and non-commercial organizations. As nowadays, the individual is faced with time pressure to finalize tasks, the deliberated increase of knowledge transfer velocity is a core capability to realize this goal. Quantitative knowledge transfer models result in more reliable predictions about the duration of knowledge transfers. These allow the target-oriented modification of knowledge transfer situations so that processes speed up, private firms are more competitive and public services are faster to citizens.
Originality/value
Time consumption is an increasingly relevant factor in contemporary business but so far not been explored in experiments at all. This study extends current knowledge by considering quantitative effects on knowledge velocity and improved knowledge transfers.
With the further development of more and more production machines into cyber-physical systems, and their greater integration with artificial intelligence (AI) techniques, the coordination of intelligent systems is a highly relevant target factor for the operation and improvement of networked processes, such as they can be found in cross-organizational production contexts spanning multiple distributed locations. This work aims to extend prior research on managing their artificial knowledge transfers as coordination instrument by examining effects of different activation types (respective activation rates and cycles) on by Artificial Neural Network (ANN)-instructed production machines. For this, it provides a new integration type of ANN-based cyber-physical production system as a tool to research artificial knowledge transfers: In a design-science-oriented way, a prototype of a simulation system is constructed as Open Source information system which will be used in on-building research to (I) enable research on ANN activation types in production networks, (II) illustrate ANN-based production networks disrupted by activation types and clarify the need for harmonizing them, and (III) demonstrate conceptual management interventions. This simulator shall establish the importance of site-specific coordination mechanisms and novel forms of management interventions as drivers of efficient artificial knowledge transfer.
Traditionally, business models and software designs used to model the usage of artificial intelligence (AI) at a very specific point in the process or rather fix implemented application. Since applications can be based on AI, such as networked artificial neural networks (ANN) on top of which applications are installed, these on-top applications can be instructed directly from their underlying ANN compartments [1]. However, with the integration of several AI-based systems, their coordination is a highly relevant target factor for the operation and improvement of networked processes, such as they can be found in cross-organizational production contexts spanning multiple distributed locations. This work aims to extend prior research on managing artificial knowledge transfers among interlinked AIs as coordination instrument by examining effects of different activation types (respective activation rates and cycles) on by ANN-instructed production machines. In a design-science-oriented way, this paper conceptualizes rhythmic state descriptions for dynamic systems and associated 14 experiment designs. Two experiments have been realized, analyzed and evaluated thereafter in regard with their activities and processes induced. Findings show that the simulator [2] used and experiments designed and realized, here, (I) enable research on ANN activation types, (II) illustrate ANN-based production networks disrupted by activation types and clarify the need for harmonizing them. Further, (III) management interventions are derived for harmonizing interlinked ANNs. This study establishes the importance of site-specific coordination mechanisms and novel forms of management interventions as drivers of efficient artificial knowledge transfer.
Die interventionelle Behandlung des Vorhofflimmerns verursacht häufiger als in der Vergangenheit wahrgenommen eine Beeinträchtigung benachbarter Gewebe und Organe. Im Vordergrund der Betrachtungen dieser Arbeit stehen Schäden des Oesophagus, die aufgrund der schlechten Vorhersagbarkeit, des zeitlich verzögerten Auftretens und der fatalen Prognose bei Ausbildung einer atrio-oesophagealen Fistel besondere Relevanz haben.
Das Vorhofflimmern selbst ist nicht mit einer unmittelbaren vitalen Bedrohung verbunden, aber durch seine Komplikationen (z.B. Herzinsuffizienz, Schlaganfall) dennoch prognostisch relevant. Durch Antiarrhythmika gelingt keine Verbesserung der Rhythmuskontrolle (Arrhythmie-Freiheit), eine katheterinterventionelle Behandlung ist der medikamentösen Therapie überlegen. Durch eine frühzeitige und erfolgreiche Behandlung des Vorhofflimmerns konnte eine Verbesserung klinischer Endpunkte und der Prognose erreicht werden. Das Risiko einer invasiven Behandlung (insbesondere hinsichtlich des Auftretens prognoserelevanter Komplikationen) muss jedoch bei der Indikationsstellung und der Prozedur-Durchführung bedacht und gegenüber den günstigen Effekten der Behandlung abgewogen werden.
Untersuchungen zur Vermeidung der sehr seltenen atrio-oesophagealen Fisteln bedienen sich Surrogat-Parametern, hier bisher ausschließlich den ablationsinduzierten Schleimhaut-Läsionen des Oesophagus. Die Untersuchungen dieser Arbeit zeigen ein komplexeres Bild der (peri)-oesophagealen Schädigungen nach Vorhofflimmern-Ablation mit thermischen Energiequellen.
(1) Neue Definition der Oesophagus-Schäden: Oesophageale und perioesophageale Beeinträchtigungen treten sehr häufig auf (nach der hier verwendeten erweiterten Definition bei zwei Drittel der Patienten) und sind unabhängig von der verwendeten Ablationsenergie. Unterschiede finden sich in den Manifestationen der Oesophagus-Schäden für die verschiedenen Energie-Protokolle, ohne dass der Mechanismus hierfür aufgeklärt ist. Diese Arbeit beschreibt die unterschiedlichen Ausprägungen thermischer Oesophagus-Schäden, deren Determinanten und pathophysiologische Relevanz.
(2) Die Detektion (zum Teil subtiler) Oesophagus-Schäden ist maßgeblich von der Intensität der Nachsorge abhängig. Eine Beschränkung auf subjektive Schilderungen (z.B. Schmerzen beim Schluckakt, Sodbrennen) ist irreführend, die Mehrzahl der Veränderungen bleibt asymptomatisch, die Symptome der ausgebildeten atrio-oesophagealen Fistel (meist nach mehreren Wochen) bereits mit einer sehr schlechten Prognose belastet. Eine Endoskopie der Speiseröhre findet in den meisten elektrophysiologischen Zentren nicht oder nur bei anhaltenden Symptomen statt und kann ausschließlich Mukosa-Läsionen nachweisen. Damit wird das Ausmaß des oesophagealen und perioesophagealen Schadens bei Weitem unterschätzt. Veränderungen des perioesophagealen Raums, deren klinische Relevanz (noch) unklar ist, werden nicht erfasst, und damit ein Wandödem und Schäden im Gewebe zwischen linkem Vorhof und Speiseröhre (einschl. Nerven und Gefäßen) ignoriert.
Die Studien tragen auch zur Neubewertung etablierter Messgrößen und Risikofaktoren der Oesophagus-Schäden bei.
(3) Das Temperaturmonitoring im Oesophagus anhand der Maximalabweichungen ist erst für Extremwerte aussagekräftig und dadurch nicht hilfreich, Oesophagus-Läsionen zu vermeiden. Die komplexe Analyse der Temperatur-Rohdaten (bisher nur offline möglich) liefert in der AUC für RF-Ablationen einen prädiktiven Parameter für Oesophagus-Schäden, der eine Strukturierung der weiteren endoskopischen Diagnostik erlaubt. Ein vergleich¬barer Wert für die Cryoablationen konnte in den Analysen nicht gefunden werden.
(4) Eine chronische Entzündung des unteren Oesophagus-Drittels behindert nicht nur das Abheilen einer thermischen Oesophagus-Läsion, sondern kann das Auftreten solcher Läsionen durch die Ablation begünstigen. Die große Zahl vorbestehender Oesophagus-Veränderungen, die eine erhöhte Vulnerabilität anzeigen, und die Bedeutung für die Ent¬stehung thermischer Läsionen können der Ansatzpunkt präventiver Maßnahmen sein.
Ergänzend werden Ausprägungen der Oesophagus-Schäden durch umfangreiche Diagnostik erfasst und beschrieben, die aus pathophysiologischen Überlegungen relevant sein können.
(5) Die systematische Erweiterung der bildgebenden Diagnostik auf den perioesophagealen Raum durch Endosonographie zeigte, dass Schleimhaut-Läsionen alleine nur einen geringen Teil der Oesophagus-Schäden darstellen. Schleimhaut-Läsionen infolge einer instrumentellen Verletzung sind nicht mit dem Risiko der Ausbildung einer atrio-oesophagealen Fistel verbunden und unterstreichen die pathophysiologische Relevanz der perioesophagealen Veränderungen.
(6) Eine funktionelle Diagnostik thermischer Schäden des perioesophagealen Vagus-Plexus identifiziert Patienten mit Oesophagus-Schäden, die bildgebend nicht erfasst wurden, jedoch in ihren Auswirkungen (Nahrungsretention und gastro-oesophagealer Reflux) zur Läsionsprogression beitragen können.
Nils-Hendrik Grohmann beschäftigt sich mit dem noch andauernden Stärkungsprozess der UN-Menschenrechtsvertragsorgane. Er analysiert, welche rechtlichen Befugnisse die Ausschüsse haben, ob sie von sich aus Vorschläge einbringen können und inwieweit sie ihre Verfahrensweisen bisher aufeinander abgestimmt haben. Ein weiterer Schwerpunkt liegt auf der Zusammenarbeit zwischen den verschiedenen Ausschüssen und der Frage, welche Rolle das Treffen der Vorsitzenden bei der Stärkung spielen kann.
Nils-Hendrik Grohmann beschäftigt sich mit dem noch andauernden Stärkungsprozess der UN-Menschenrechtsvertragsorgane. Er analysiert, welche rechtlichen Befugnisse die Ausschüsse haben, ob sie von sich aus Vorschläge einbringen können und inwieweit sie ihre Verfahrensweisen bisher aufeinander abgestimmt haben. Ein weiterer Schwerpunkt liegt auf der Zusammenarbeit zwischen den verschiedenen Ausschüssen und der Frage, welche Rolle das Treffen der Vorsitzenden bei der Stärkung spielen kann.
Organic-inorganic hybrids based on P3HT and mesoporous silicon for thermoelectric applications
(2024)
This thesis presents a comprehensive study on synthesis, structure and thermoelectric transport properties of organic-inorganic hybrids based on P3HT and porous silicon. The effect of embedding polymer in silicon pores on the electrical and thermal transport is studied. Morphological studies confirm successful polymer infiltration and diffusion doping with roughly 50% of the pore space occupied by conjugated polymer. Synchrotron diffraction experiments reveal no specific ordering of the polymer inside the pores. P3HT-pSi hybrids show improved electrical transport by five orders of magnitude compared to porous silicon and power factor values comparable or exceeding other P3HT-inorganic hybrids. The analysis suggests different transport mechanisms in both materials. In pSi, the transport mechanism relates to a Meyer-Neldel compansation rule. The analysis of hybrids' data using the power law in Kang-Snyder model suggests that a doped polymer mainly provides charge carriers to the pSi matrix, similar to the behavior of a doped semiconductor. Heavily suppressed thermal transport in porous silicon is treated with a modified Landauer/Lundstrom model and effective medium theories, which reveal that pSi agrees well with the Kirkpatrick model with a 68% percolation threshold. Thermal conductivities of hybrids show an increase compared to the empty pSi but the overall thermoelectric figure of merit ZT of P3HT-pSi hybrid exceeds both pSi and P3HT as well as bulk Si.
Learning in virtual, immersive environments must be well-designed to foster learning instead of overwhelming and distracting the learner. So far, learning instructions based on cognitive load theory recommend keeping the learning instructions clean and simple to reduce the extraneous cognitive load of the learner to foster learning performance. The advantages of immersive learning, such as multiple options for realistic simulation, movement and feedback, raise questions about the tension between an increase of excitement and flow with highly realistic environments on the one hand and a reduction of cognitive load by developing clean and simple surroundings on the other hand. This study aims to gain insights into learners' cognitive responses during the learning process by continuously assessing cognitive load through eye-tracking. The experiment compares two distinct immersive learning environments and varying methods of content presentation.
This paper provides novel evidence on the impact of public transport subsidies on air pollution. We obtain causal estimates by leveraging a unique policy intervention in Germany that temporarily reduced nationwide prices for regional public transport to a monthly flat rate price of 9 Euros. Using DiD estimation strategies on air pollutant data, we show that this intervention causally reduced a benchmark air pollution index by more than eight percent and, after its termination, increased again. Our results illustrate that public transport subsidies – especially in the context of spatially constrained cities – offer a viable alternative for policymakers and city planers to improve air quality, which has been shown to crucially affect health outcomes.
This study aims to bring together scattered research findings on user satisfaction with mobile government apps into a unified framework. The researchers analyzed 70 high-quality papers from leading journals and conferences and systematically integrated different frameworks and case studies to reflect the importance of the field over time while also highlighting methodological and geographical research gaps. The study achieved a significant methodological advance by developing codebooks for empirical analysis utilizing the App Store. This approach validated the framework’s dimensions on 8,524 reviews, demonstrating the framework’s applicability to platform-based apps and identifying critical areas for future research. Combining academic insights with practical findings, this research provides comprehensive guidance for developing and evaluating user-centered mobile government apps, facilitating improved service delivery and alignment with user expectations.