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Moss-microbe associations are often characterised by syntrophic interactions between the microorganisms and their hosts, but the structure of the microbial consortia and their role in peatland development remain unknown.
In order to study microbial communities of dominant peatland mosses, Sphagnum and brown mosses, and the respective environmental drivers, four study sites representing different successional stages of natural northern peatlands were chosen on a large geographical scale: two brown moss-dominated, circumneutral peatlands from the Arctic and two Sphagnum-dominated, acidic peat bogs from subarctic and temperate zones.
The family Acetobacteraceae represented the dominant bacterial taxon of Sphagnum mosses from various geographical origins and displayed an integral part of the moss core community. This core community was shared among all investigated bryophytes and consisted of few but highly abundant prokaryotes, of which many appear as endophytes of Sphagnum mosses. Moreover, brown mosses and Sphagnum mosses represent habitats for archaea which were not studied in association with peatland mosses so far. Euryarchaeota that are capable of methane production (methanogens) displayed the majority of the moss-associated archaeal communities. Moss-associated methanogenesis was detected for the first time, but it was mostly negligible under laboratory conditions. Contrarily, substantial moss-associated methane oxidation was measured on both, brown mosses and Sphagnum mosses, supporting that methanotrophic bacteria as part of the moss microbiome may contribute to the reduction of methane emissions from pristine and rewetted peatlands of the northern hemisphere.
Among the investigated abiotic and biotic environmental parameters, the peatland type and the host moss taxon were identified to have a major impact on the structure of moss-associated bacterial communities, contrarily to archaeal communities whose structures were similar among the investigated bryophytes. For the first time it was shown that different bog development stages harbour distinct bacterial communities, while at the same time a small core community is shared among all investigated bryophytes independent of geography and peatland type.
The present thesis displays the first large-scale, systematic assessment of bacterial and archaeal communities associated both with brown mosses and Sphagnum mosses. It suggests that some host-specific moss taxa have the potential to play a key role in host moss establishment and peatland development.
The increasing number of known exoplanets raises questions about their demographics and the mechanisms that shape planets into how we observe them today. Young planets in close-in orbits are exposed to harsh environments due to the host star being magnetically highly active, which results in high X-ray and extreme UV fluxes impinging on the planet. Prolonged exposure to this intense photoionizing radiation can cause planetary atmospheres to heat up, expand and escape into space via a hydrodynamic escape process known as photoevaporation. For super-Earth and sub-Neptune-type planets, this can even lead to the complete erosion of their primordial gaseous atmospheres. A factor of interest for this particular mass-loss process is the activity evolution of the host star. Stellar rotation, which drives the dynamo and with it the magnetic activity of a star, changes significantly over the stellar lifetime. This strongly affects the amount of high-energy radiation received by a planet as stars age. At a young age, planets still host warm and extended envelopes, making them particularly susceptible to atmospheric evaporation. Especially in the first gigayear, when X-ray and UV levels can be 100 - 10,000 times higher than for the present-day sun, the characteristics of the host star and the detailed evolution of its high-energy emission are of importance.
In this thesis, I study the impact of stellar activity evolution on the high-energy-induced atmospheric mass loss of young exoplanets. The PLATYPOS code was developed as part of this thesis to calculate photoevaporative mass-loss rates over time. The code, which couples parameterized planetary mass-radius relations with an analytical hydrodynamic escape model, was used, together with Chandra and eROSITA X-ray observations, to investigate the future mass loss of the two young multiplanet systems V1298 Tau and K2-198. Further, in a numerical ensemble study, the effect of a realistic spread of activity tracks on the small-planet radius gap was investigated for the first time. The works in this thesis show that for individual systems, in particular if planetary masses are unconstrained, the difference between a young host star following a low-activity track vs. a high-activity one can have major implications: the exact shape of the activity evolution can determine whether a planet can hold on to some of its atmosphere, or completely loses its envelope, leaving only the bare rocky core behind. For an ensemble of simulated planets, an observationally-motivated distribution of activity tracks does not substantially change the final radius distribution at ages of several gigayears. My simulations indicate that the overall shape and slope of the resulting small-planet radius gap is not significantly affected by the spread in stellar activity tracks. However, it can account for a certain scattering or fuzziness observed in and around the radius gap of the observed exoplanet population.
Development of a CRISPR/Cas gene editing technique for the coccolithophore Chrysotila carterae
(2024)
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.
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.
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.
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)
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.
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.
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.
Kochbücher à la religion
(2024)
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.
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.
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.
The landscape of software self-adaptation is shaped in accordance with the need to cost-effectively achieve and maintain (software) quality at runtime and in the face of dynamic operation conditions. Optimization-based solutions perform an exhaustive search in the adaptation space, thus they may provide quality guarantees. However, these solutions render the attainment of optimal adaptation plans time-intensive, thereby hindering scalability. Conversely, deterministic rule-based solutions yield only sub-optimal adaptation decisions, as they are typically bound by design-time assumptions, yet they offer efficient processing and implementation, readability, expressivity of individual rules supporting early verification. Addressing the quality-cost trade-of requires solutions that simultaneously exhibit the scalability and cost-efficiency of rulebased policy formalism and the optimality of optimization-based policy formalism as explicit artifacts for adaptation. Utility functions, i.e., high-level specifications that capture system objectives, support the explicit treatment of quality-cost trade-off. Nevertheless, non-linearities, complex dynamic architectures, black-box models, and runtime uncertainty that makes the prior knowledge obsolete are a few of the sources of uncertainty and subjectivity that render the elicitation of utility non-trivial.
This thesis proposes a twofold solution for incremental self-adaptation of dynamic architectures. First, we introduce Venus, a solution that combines in its design a ruleand an optimization-based formalism enabling optimal and scalable adaptation of dynamic architectures. Venus incorporates rule-like constructs and relies on utility theory for decision-making. Using a graph-based representation of the architecture, Venus captures rules as graph patterns that represent architectural fragments, thus enabling runtime extensibility and, in turn, support for dynamic architectures; the architecture is evaluated by assigning utility values to fragments; pattern-based definition of rules and utility enables incremental computation of changes on the utility that result from rule executions, rather than evaluating the complete architecture, which supports scalability. Second, we introduce HypeZon, a hybrid solution for runtime coordination of multiple off-the-shelf adaptation policies, which typically offer only partial satisfaction of the quality and cost requirements. Realized based on meta-self-aware architectures, HypeZon complements Venus by re-using existing policies at runtime for balancing the quality-cost trade-off.
The twofold solution of this thesis is integrated in an adaptation engine that leverages state- and event-based principles for incremental execution, therefore, is scalable for large and dynamic software architectures with growing size and complexity. The utility elicitation challenge is resolved by defining a methodology to train utility-change prediction models. The thesis addresses the quality-cost trade-off in adaptation of dynamic software architectures via design-time combination (Venus) and runtime coordination (HypeZon) of rule- and optimization-based policy formalisms, while offering supporting mechanisms for optimal, cost-effective, scalable, and robust adaptation. The solutions are evaluated according to a methodology that is obtained based on our systematic literature review of evaluation in self-healing systems; the applicability and effectiveness of the contributions are demonstrated to go beyond the state-of-the-art in coverage of a wide spectrum of the problem space for software self-adaptation.
Die vorliegende Masterarbeit widmet sich der Frage, inwiefern die neuesten Lehrwerke für den gymnasialen Französischunterricht, Découvertes 1 (Klett) und À plus 1 (Cornelsen) aus dem Jahr 2020, sprachvernetzende Inhalte nutzen, um auf vorgelernte Sprachen und frühere Spracherwerbsprozesse hinzuweisen oder darauf zurückzugreifen. Der Fokus liegt dabei auf der Schul- und/oder Erstsprache Deutsch sowie der ersten Fremdsprache Englisch, wobei auch andere auftretende Sprachen in die Untersuchung einbezogen werden.
Die Arbeit leistet einen Beitrag zum fachdidaktischen Diskurs bezüglich mehrsprachigkeitsdidaktischer Inhalte in Fremdsprachenlehrwerken. Darüber hinaus kann sie Lehrkräften aufzeigen, wie diese aktuellen Lehrwerke ihren mehrsprachigkeitsorientierten Unterricht begleiten können.
Die Einleitung betont die Relevanz der Sprachvernetzung für den Fremdsprachenunterricht, insbesondere im Hinblick auf die individuelle Mehrsprachigkeit der Schüler*innen. Es wird auf das Potenzial des interlingualen Transfers hingewiesen, das u. a. in einer Lernerleichterung sowie der Förderung der Sprachbewusstheit und der Sprachlernbewusstheit besteht.
In Kapitel 2 werden die theoretischen Grundlagen für die Analyse gelegt, indem Mehrsprachigkeit und Mehrsprachigkeitsdidaktik, Sprachvernetzung und ihr Potenzial näher betrachtet werden. Zudem wird anhand des Deutschen und Englischen aufgezeigt, welches sprachliche Transferpotenzial im Anfangsunterricht Französisch eingebracht werden könnte. Auch die Bedingungen dafür, dass Schüler*innen den interlingualen Transfer in ihrem Spracherwerb einsetzen, werden besprochen.
Kapitel 3 gibt einen Überblick über den Forschungsstand zu Sprachvernetzung und Mehrsprachigkeit in Fremdsprachenlehrwerken und identifiziert die Forschungslücke, die diese Arbeit zu schließen versucht.
In Kapitel 4 werden die Forschungsfrage und ihre Unterfragen formuliert, die untersuchten Lehrwerke beschrieben und die Auswahl der Lehrwerke und der untersuchten Lehrwerkskomponenten begründet. Zudem wird die Methodik der vergleichenden Lehrwerkanalyse erläutert.
Die Ergebnisse der Analyse werden in Kapitel 5 ausführlich dargestellt. Es wird aufgezeigt, welche sprachvernetzenden Inhalte in den jeweiligen Lehrwerken vorkommen – in welcher Form und unter Einbezug welcher Sprachen und sprachlichen Ebenen.
In Kapitel 6 werden die Ergebnisse diskutiert und analysiert, wobei auf die Mehrsprachigkeitskonzepte der Lehrwerke und die Trends bei den sprachvernetzenden Inhalten eingegangen wird.
Im abschließenden Kapitel 7 wird zusammenfassend betont, dass beide Lehrwerke viele sprachvernetzende Inhalte anbieten, die das Potenzial haben, mehrsprachigkeitsdidaktisches Arbeiten zu unterstützen. Insbesondere auf der Produktionsebene werden jedoch noch zu wenige Transferprozesse initiiert. Zudem wird aufgezeigt, welche weiteren Untersuchungen ergänzend möglich sind, z. B. hinsichtlich des Einsatzes der sprachvernetzenden Inhalte im Unterricht.
Unternehmenssteuerrecht
(2024)
Das Unternehmenssteuerrecht gilt als schwierige Spezialmaterie. Wer in diesem praktisch wichtigen Rechtsgebiet den Durchblick behalten will, muss die relevanten Zusammenhänge verstehen. Der stringente Aufbau und zahlreiche – zumeist an die BFH-Rechtsprechung angelehnte – Beispiele des „Hüttemann/Schön" erleichtern ebenso wie viele Querverweise den Überblick und die Durchdringung der Zusammenhänge.
Das Werk eröffnet nicht nur interessierten Studierenden der Rechtswissenschaften, Wirtschaftswissenschaften und Steuerwissenschaften einen systematischen Zugang zum Unternehmenssteuerrecht. Er richtet sich auch an Praktiker, die bei ihrer beratenden und gestaltenden Tätigkeit auf hinreichende Kenntnisse und ein vertieftes Verständnis dieses Rechtsgebiets angewiesen sind.
The public health insurance in Germany will face huge economic challenges in the upcoming years. New diagnostic and therapeutic methods as well as the demographic change contribute to constantly rising expenditure. Although incentives for health-promoting behaviour or financial sanctions for an unhealthy lifestyle have been already discussed in the past, there has been a general reluctance to legally establish corresponding mechanisms for fear of eroding solidarity and increasing state control. In the course of the Coronavirus pandemic however, a stronger awareness rose to the fact that personal health-related life choices can have a huge impact on the stability of the healthcare system including public health insurance. Not only in Germany but throughout much of Europe, the pandemic led to a new and more fundamental debate about the relationship between individual responsibility for personal health and the wider responsibility for public health assumed by the community of solidarity.
This work analyzed functional and regulatory aspects of the so far little characterized EPSIN N-terminal Homology (ENTH) domain-containing protein EPSINOID2 in Arabidopsis thaliana. ENTH domain proteins play accessory roles in the formation of clathrin-coated vesicles (CCVs) (Zouhar and Sauer 2014). Their ENTH domain interacts with membranes and their typically long, unstructured C-terminus contains binding motifs for adaptor protein complexes and clathrin itself. There are seven ENTH domain proteins in Arabidopsis. Four of them possess the canonical long C-terminus and participate in various, presumably CCV-related intracellular transport processes (Song et al. 2006; Lee et al. 2007; Sauer et al. 2013; Collins et al. 2020; Heinze et al. 2020; Mason et al. 2023). The remaining three ENTH domain proteins, however, have severely truncated C-termini and were termed EPSINOIDs (Zouhar and Sauer 2014; Freimuth 2015). Their functions are currently unclear. Preceding studies focusing on EPSINOID2 indicated a role in root hair formation: epsinoid2 T DNA mutants exhibited an increased root hair density and EPSINOID2-GFP was specifically located in non-hair cell files in the Arabidopsis root epidermis (Freimuth 2015, 2019).
In this work, it was clearly shown that loss of EPSINOID2 leads to an increase in root hair density through analyses of three independent mutant alleles, including a newly generated CRISPR/Cas9 full deletion mutant. The ectopic root hairs emerging from non-hair positions in all epsinoid2 mutant alleles are most likely not a consequence of altered cell fate, because extensive genetic analyses placed EPSINOID2 downstream of the established epidermal patterning network. Thus, EPSINOID2 seems to act as a cell autonomous inhibitor of root hair formation. Attempts to confirm this hypothesis by ectopically overexpressing EPSINOID2 led to the discovery of post-transcriptional and -translational regulation through different mechanisms. One involves the little characterized miRNA844-3p. Interference with this pathway resulted in ectopic EPSINOID2 overexpression and decreased root hair density, confirming it as negative factor in root hair formation. A second mechanism likely involves proteasomal degradation. Treatment with proteasomal inhibitor MG132 led to EPSINOID2-GFP accumulation, and a KEN box degron motif was identified in the EPSINOID2 sequence associated with degradation through a ubiquitin/proteasome-dependent pathway. In line with a tight dose regulation, genetic analyses of all three mutant alleles indicate that EPSINOID2 is haploinsufficient. Lastly, it was revealed that, although EPSINOID2 promoter activity was found in all epidermal cells, protein accumulation was observed in N-cells only, hinting at yet another layer of regulation.
Der russische Krimi
(2024)
Die erste umfassende Darstellung des Kriminalgenres in Russland. Sie geht auf Bücher und Filme ein und berücksichtigt die Debatten der Literaturkritik, da sich die Kulturpolitik während der sowjetischen Jahrzehnte schwer damit tat, dem Kriminalgenre überhaupt ein Existenzrecht zubilligen. Sympathie für die Miliz zu erzeugen wurde schließlich offizieller Zweck dieses politisch zu einer Nischenexistenz gedrängten Genres. Entsprechend liegt ein Akzent der Studie auf der Ideologie, besonders bei der Darstellung der Helden und ihrer Gegner und der Lebenswelt, die die Leser als ihre wiedererkennen sollten. Dabei erfahren sie eine Menge über die Gesellschaft, vor allem über deren sonst eher verschwiegene Schattenseiten.
Nicht zuletzt wegen der langen Entbehrung spannender Texte wurde der Krimi nach dem Ende des Sozialismus zu dem Bestsellergenre schlechthin. Am Bespiel des Frauenkrimis (Marinina und Nachfolgerinnen) und des postmodernen Krimis (Akunin) wird die postsowjetische Entwicklung bis in die 2010er Jahre gezeigt.
This thesis presents an attempt to use source code synthesised from Coq formalisations of device drivers for existing (micro)kernel operating systems, with a particular focus on the Linux Kernel.
In the first part, the technical background and related work are described. The focus is here on the possible approaches to synthesising certified software with Coq, namely the extraction to functional languages using the Coq extraction plugin and the extraction to Clight code using the CertiCoq plugin. It is noted that the implementation of CertiCoq is verified, whereas this is not the case for the Coq extraction plugin. Consequently, there is a correctness guarantee for the generated Clight code which does not hold for the code being generated by the Coq extraction plugin. Furthermore, the differences between user space and kernel space software are discussed in relation to Linux device drivers. It is elaborated that it is not possible to generate working Linux kernel module components using the Coq extraction plugin without significant modifications. In contrast, it is possible to produce working user space drivers both with the Coq extraction plugin and CertiCoq. The subsequent parts describe the main contributions of the thesis.
In the second part, it is demonstrated how to extend the Coq extraction plugin to synthesise foreign function calls between the functional language OCaml and the imperative language C. This approach has the potential to improve the type-safety of user space drivers. Furthermore, it is shown that the code being synthesised by CertiCoq cannot be used in kernel space without modifications to the necessary runtime. Consequently, the necessary modifications to the runtimes of CertiCoq and VeriFFI are introduced, resulting in the runtimes becoming compatible components of a Linux kernel module. Furthermore, justifications for the transformations are provided and possible further extensions to both plugins and solutions to failing garbage collection calls in kernel space are discussed.
The third part presents a proof of concept device driver for the Linux Kernel. To achieve this, the event handler of the original PC Speaker driver is partially formalised in Coq. Furthermore, some relevant formal properties of the formalised functionality are discussed. Subsequently, a kernel module is defined, utilising the modified variants of CertiCoq and VeriFFI to compile a working device driver. It is furthermore shown that it is possible to compile the synthesised code with CompCert, thereby extending the guarantee of correctness to the assembly layer. This is followed by a performance evaluation that compares a naive formalisation of the PC speaker functionality with the original PC Speaker driver pointing out the weaknesses in the formalisation and possible improvements. The part closes with a summary of the results, their implications and open questions being raised.
The last part lists all used sources, separated into scientific literature, documentations or reference manuals and artifacts, i.e. source code.
With the many challenges facing the agricultural system, such as water scarcity, loss of arable land due to climate change, population growth, urbanization or trade disruptions, new agri-food systems are needed to ensure food security in the future. In addition, healthy diets are needed to combat non-communicable diseases. Therefore, plant-based diets rich in health-promoting plant secondary metabolites are desirable. A saline indoor farming system is representing a sustainable and resilient new agrifood system and can preserve valuable fresh water. Since indoor farming relies on artificial lighting, assessment of lighting conditions is essential. In this thesis, the cultivation of halophytes in a saline indoor farming system was evaluated and the influence of cultivation conditions were assessed in favor of improving the nutritional quality of halophytes for human consumption. Therefore, five selected edible halophyte species (Brassica oleracea var. palmifolia, Cochlearia officinalis, Atriplex hortensis, Chenopodium quinoa, and Salicornia europaea) were cultivated in saline indoor farming. The halophyte species were selected for to their salt tolerance levels and mechanisms. First, the suitability of halophytes for saline indoor farming and the influence of salinity on their nutritional properties, e.g. plant secondary metabolites and minerals, were investigated. Changes in plant performance and nutritional properties were observed as a function of salinity. The response to salinity was found to be species-specific and related to the salt tolerance mechanism of the halophytes. At their optimal salinity levels, the halophytes showed improved carotenoid content. In addition, a negative correlation was found between the nitrate and chloride content of halophytes as a function of salinity. Since chloride and nitrate can be antinutrient compounds, depending on their content, monitoring is essential, especially in halophytes. Second, regional brine water was introduced as an alternative saline water resource in the saline indoor farming system. Brine water was shown to be feasible for saline indoor farming
of halophytes, as there was no adverse effect on growth or nutritional properties, e.g. carotenoids. Carotenoids were shown to be less affected by salt composition than by salt concentration. In addition, the interaction between the salinity and the light regime in indoor farming and greenhouse cultivation has been studied. There it was shown that interacting light regime and salinity alters the content of carotenoids and chlorophylls. Further, glucosinolate and nitrate content were also shown to be influenced by light regime. Finally, the influence of UVB light on halophytes was investigated using supplemental narrow-band UVB LEDs. It was shown that UVB light affects the growth, phenotype and metabolite profile of halophytes and that the UVB response is species specific. Furthermore, a modulation of carotenoid content in S. europaea could be achieved to enhance health-promoting properties and thus improve nutritional quality. This was shown to be dose-dependent and the underlying mechanisms of carotenoid accumulation were also investigated. Here it was revealed that carotenoid accumulation is related to oxidative stress.
In conclusion, this work demonstrated the potential of halophytes as alternative vegetables produced in a saline indoor farming system for future diets that could contribute to ensuring food security in the future. To improve the sustainability of the saline indoor farming system, LED lamps and regional brine water could be integrated into the system. Since the nutritional properties have been shown to be influenced by salt, light regime and UVB light, these abiotic stressors must be taken into account when considering halophytes as alternative vegetables for human nutrition.
-Ottmar Ette, Ingo Schwarz: „Ein junges, neues Geschlecht wird besseres liefern als das alte“. Ein Empfehlungsbrief Alexander von Humboldts für Carl Ludwig
-GAO Hong: Nachgedanken zur Übersetzung des ersten Bandes von Humboldts Kosmos
-Tobias Kraft: Neue Quellen zu Humboldts Kuba-Forschung. Das „Digitale Dossier“ des Proyecto Humboldt Digital (2019 – 2023)
-Vera Kutzinski: Off-Road Adventures: Reading Statistics in Alexander von Humboldt’s Political Essay on the Kingdom of New Spain
-Krzysztof Zielnica: Alexander von Humboldt und Polen – zum 150. Jahrestag seiner Reise nach Warschau. Mit einleitenden Worten von Ingo Schwarz