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Amtliche Bekanntmachungen, 55. Jahrgang, Nr. 27
No full textAkkreditierungsbeschluss vom 23. Januar 2024 Cyber Security (M.Sc.) vom 14. April 202
Search for a heavy charged Higgs boson decaying into a <em>W</em> boson and a 125 GeV Higgs boson, in final states with leptons and jets, with the ATLAS experiment at the LHC
Get PDFThis thesis presents a first search for a heavy charged Higgs boson produced in association with a top- and a bottom-quark, and decaying into a W boson and a 125 GeV Higgs boson decaying subsequently into a pair of b-quarks. The search is performed in final states with leptons and jets using proton-proton collision data at a center-of-mass energy of 13 TeV, recorded with the ATLAS detector during Run 2 of the LHC at CERN. This dataset corresponds to a total integrated luminosity of 140 fb-1. Multivariate analysis techniques are used to reconstruct the charged Higgs boson candidate, and to improve the background rejection. The reconstructed invariant mass distribution of the charged Higgs boson candidate is scrutinised for an excess in data events in the mass range from 250 GeV to 3 TeV. No significant excess is observed, and 95% confidence level upper limits are set between 2.77 pb and 1.18 fb on the production cross section times branching ratio of the charged Higgs boson decays
Effects of structural differences of biflavonoids from fruits of the Brazilian peppertree (<em>Schinus terebinthifolius</em> Raddi) on food-associated microorganisms
Get PDFEconomic, health, or sensory aspects are affected by microbial contamination of food. The preservation of food is crucial for ensuring food safety and reducing economic losses. With increasing resistance, allergies, and intolerances to conventional preservatives, the interest of consumers in natural preservatives is growing. Plants, such as Schinus terebinthifolius, which belongs to the Anacardiaceae family, are known to contain a diverse range of phytochemicals with bioactive properties. Schinus fruits contain several phenolic compounds, including gallotannins and flavonoids. Flavonoids have a wide range of chemical structures that greatly affect their biological activity, e.g., as antioxidants, anti-inflammatory or antibacterial agents.
The present thesis aimed to investigate the effects of structural differences of flavonoids, including tetrahydroamentoflavone, amentoflavone, agathisflavone, and their monomers apigenin and naringenin, on planktonic cells, biofilm formation, bacterial membrane properties, and components of pigment-forming food-associated microorganisms.
Our investigations showed that the antibacterial efficacy of flavonoids is influenced by their degree of oxidation and dimerization. Tetrahydroamentoflavone, a biflavonoid with a reduced C-ring at positions I-2,3 and II-2,3, exhibited the highest antibacterial activity, particularly against Gram-positive microorganisms. A minimum bactericidal concentration of 0.063 mg/ml was observed against Bacillus subtilis. Tetrahydroamentoflavone also exhibited remarkable inhibitory effects of biofilm formation, reducing biofilms by up to 99% in Listeria innocua and Staphylococcus carnosus.
Analysis of the effects of flavonoids on bacterial lipids and membrane properties showed a significant influence on carotenoids, fatty acids, menaquinones, and membrane fluidity and suggested a stress response of the microorganisms to the envelope or adaptive mechanisms.
The addition of naringenin led to an increase in carotenoid content and a simultaneous decrease in membrane fluidity, causing changes in the fatty acid composition of the bacteria, such as an increase in longer-chain fatty acids. This led to the assumption of membrane stabilization and alteration of the penetration barrier. An adjustment of the permeability barrier can also be inferred from the addition of amentoflavone, as it reduces the total carotenoid content of Micrococcus luteus J3.
Tetrahydroamentoflavone addition mainly reduced the staphyloxanthin content in Staphylococcus xylosus strains and showed similar trends to naringenin exposure. Considering the reduction of staphyloxanthin, the impact on biofilm formation, and the CCS value of 220.99 ± 0.27 Å2, which suggests steric hindrance, interactions with external cell components, particularly cell wall interactions, are conceivable and might be crucial for the higher antibacterial efficacy of the biflavonoid tetrahydroamentoflavone as a promising antibacterial agent
Multimodal assessment of adult attention-deficit hyperactivity disorder using virtual reality
Get PDFAttention-deficit hyperactivity disorder (ADHD) is a complex and heterogeneous disorder. As a result of this heterogeneity, it has been difficult to identify reliable objective tests and markers for ADHD. The neuropsychological continuous performance test (CPT) has often been explored as a candidate, but it is neither sensitive nor specific enough to be used for diagnosis on its own. Adding physiological measures has been shown to improve ist diagnostic ability, suggesting that combining different assessment levels may better reflect the complexity of the disorder. Another reason for the limited usefulness of the classic CPT in ADHD assessment may also be the abstract, computer-based nature of the test. Here, a possible solution may be the addition of virtual reality (VR), as it allows the creation of immersive and realistic, yet standardized test environments. For the assessment of ADHD in children, VR-based CPTs have already shown promising results, but there is still very little research in adults.
Therefore, in this dissertation, a VR-based CPT test environment for adult ADHD, the virtual seminar room (VSR) was developed and evaluated. In addition to CPT performance, head actigraphy, eye tracking, electroencephalography, functional nearinfrared spectroscopy, and subjective experience were assessed to better capture the heterogeneity of the disorder. This multimodal VSR was evaluated in three consecutive studies. In study I, we tested the general feasibility and tolerability of the setup in a sample of healthy adults. Next, in study II, we investigated whether group differences between unmedicated adults with ADHD, medicated adults with ADHD, and healthy controls (HC) could be found in the different modalities. Finally, in study III, we used machine learning to investigate the extent to which, on a single-subject basis, unmedicated individuals with ADHD and HC could be correctly classified using the VSR parameters.
The results showed that the VSR setup was feasible and tolerable for both healthy individuals (study I and II) and those with ADHD (study II). While there was no clear evidence for a sensitivity of the VSR to medication effects in study II, significant Group differences between unmedicated individuals with ADHD and HC were found in CPT performance, actigraphy, eye tracking, and subjective experience. Further, combining these modalities via machine learning resulted in high accuracy in distinguishing the two groups in study III, underlining the diagnostic potential of the VSR and especially the importance of a multimodal approach in the assessment of adult ADHD. This potential needs to be further explored in future, large sample studies, for example by investigating the ability of the VSR to differentiate ADHD from other disorders
Integrated Robotic Learning and Planning for UAV-Based Information Gathering in Unknown Environments
No full textRobots increasingly automate tasks that require costly and precise measurements at scale. Combining advances in hardware development with recent progress in machine learning-based computer vision enables robots to collect data with onboard sensors and interpret measurements to gather information, e.g. monitoring crop conditions for breeders or cities for disaster management. Classical information-gathering missions might require the environment to be known before deployment and traditionally execute pre-programmed paths for robotic data collection. In unknown environments, robot autonomy is often limited by the need for human supervision or operation. To fully leverage the information-gathering potential, we need algorithms that enable the robot to plan actions onboard during its deployment. Mainly, robots must autonomously collect information and adapt their behaviour online in the unknown environment while considering onboard resource constraints, such as the limited energy and compute power of unmanned aerial vehicles (UAVs). This task is also known as the adaptive informative path planning problem.
The main contributions of this thesis are novel learning-based adaptive informative path planning approaches for UAV-based information gathering in unknown environments. Our approaches guide a resource-constrained UAV towards areas where it could collect informative measurements to enhance its understanding of the environment.
First, we present a new adaptive informative path planning method combining tree search-based planning with reinforcement learning to train strategies gathering continuous-valued information, such as surface temperature. Our learning-based method accelerates path replanning during deployment on a resource-constrained UAV compared to non-learning-based planning methods. In general, adaptive informative path planning methods are explicitly designed and trained for certain map representations capturing continuous-valued or discrete-valued environment information, e.g. semantic segmentation of weeds and crops. The second approach introduces a novel mathematical formulation of the adaptive informative path planning problem unifying arbitrary to-be-monitored environment information. Using our formulation, we train a single map-agnostic information-gathering strategy, performing on par or better than previous map-specific methods.
In missions that require semantically interpreting images using deep learning-based vision models, the model's prediction performance often degrades in unknown environments. Thus, costly human labelling of collected images is required to improve vision models. We propose a novel adaptive informative path planning framework for active learning of semantic segmentation models to improve a UAV's semantic vision in unknown environments. Our framework improves the model performance faster while drastically reducing the number of human-labelled images required to train the model compared to prior non-adaptive training data collection campaigns. Lastly, our fourth approach is a novel semi-supervised learning method for improving semantic vision in unknown environments to further reduce human labelling efforts. Overall, our semi-supervised method requires less than one per cent of the human-labelled pixels to maintain semantic segmentation performance similar to exhaustively labelling all image pixels.Roboter automatisieren zunehmend Aufgaben, die kostenintesive und präzise Messungen in großem Maßstab erfordern. Durch Fortschritte in der Hardwareentwicklung und im maschinellen Lernen können Roboter mittels Sensoren Daten sammeln und interpretieren, um Informationen, z. B. zur Analyse von Nutzpflanzen für Züchter oder von Städten zu Zwecken des Katastrophenmanagements, zu erfassen. Klassische Missionen zur Informationserfassung setzen eine bekannte Umgebung voraus und sammeln Daten entlang vorprogrammierter Pfade. Für die Datenerfassung in unbekannten Umgebungen ist häufig eine manuelle Überwachung oder Bedienung nötig. Um das Potenzial, Informationen zu erfassen voll auszuschöpfen, benötigen wir Algorithmen, die es dem Roboter ermöglichen, Aktionen direkt an Bord zu planen und auszuführen. Um effizient Informationen zu sammeln, müssen Roboter die unbekannte Umgebung autonom erkunden und dabei Ressourcenbeschränkungen wie z.B. begrenzte Energie- und Rechenkapazitäten eines unbemannten Luftfahrzeugs (UAV) berücksichtigen. Diese Aufgabe wird als adaptives Wegplanungsproblem bezeichnet.
Die Hauptbeiträge dieser Arbeit sind neue, lernbasierte, adaptive Wegplanungsmethoden für die UAV-basierte Informationserfassung in unbekannten Umgebungen. Unsere Methoden leiten ein ressourcenbeschränktes UAV in Regionen, in denen es informative Messungen sammeln könnte, um sein aktuelles Umgebungsverständnis zu verbessern.
Zuerst präsentieren wir eine adaptive Wegplanungsmethode, die eine Baumsuche mit bestärkenden Lernen kombiniert, um Strategien zur Erfassung von Informationen mit kontinuierlichen Werten, wie z. B. Oberflächentemperatur, zu trainieren. Unsere Methode beschleunigt die Wegplanung auf einem ressourcenbeschränkten UAV im Vergleich zu nicht lernbasierten Wegplanungsmethoden. Generell werden adaptive Wegplanungsmethoden für bestimmte Kartenrepräsentationen entwickelt und trainiert, die entweder Informationen mit kontinuierlichen oder diskreten Werten, wie z.B. die Segmentierung von Unkraut und Pflanzen, erfassen. Die zweite Methode führt eine neue Formulierung des adaptiven Wegplanungsproblems ein, die beliebige zu beobachtende Informationen vereinheitlicht, und es ermöglicht, eine karten-agnostische Strategie zur Informationserfassung zu trainieren, deren Leistung vergleichbar mit kartenspezifischen Methoden ist.
In Missionen, bei denen Bilder mittels lernbasierten Bildverarbeitungsmodellen semantisch interpretiert werden, verschlechtert sich die Modellvorhersage in unbekannten Umgebungen, sodass kostenintensive manuelle Annotationen der gesammelten Bilder zur Verbesserung des Modells erforderlich sind. Zur Verbesserung des semantischen Sehens eines UAV in unbekannten Umgebungen stellen wir ein neues adaptives Wegplanungssystem für das aktive Lernen von semantischen Segmentierungsmodellen vor. Im Vergleich zu vorherigen Kampagnen zur Trainingsdatensammlung verbessert unser System die semantische Segmentierung schneller und reduziert die Anzahl der benötigten manuell annotierten Bilder. Unsere vierte Methode ist ein halbüberwachtes Lernverfahren, um den Aufwand der manuellen Annotationen weiter zu reduzieren. Mit weniger als einem Prozent der manuell annotierten Pixeln erzielt unsere Methode eine ähnlich akkurate semantische Segmentierung wie bei der manuellen Annotation aller Pixel
Amtliche Bekanntmachungen, 55. Jahrgang, Nr. 28
No full textVierzigste Ordnung zur Änderung der Beitragsordnung der Studierendenschaft der Rheinischen Friedrich-Wilhelms-Universität Bonn - XL. Beitragsordnungsänderungsordnung (BOÄO XL) - vom 12. Mai 202
Economic geographies of large-scale renewable energies development in Kenya : Financing, governance and infrastructures
Get PDFEnergy transition theories and studies have made important contributions to our knowledge of the challenges and possibilities for achieving sustainable energy transition and more sustainable societies. However, this body of work can be enhanced through the incorporation of geographical perspectives and power relations as forces shaping the development and materialization of energy transition projects in practice. This thesis applies a geographic lens, as part of its analytical framework, to study the actor constellations, processes and linkages involved in the development of large-scale renewable energy (LSRE) projects in Kenya. It focuses on the key arrangements thereof, namely, financing, governance and infrastructures. The research questions of the study are answered through dedicated research contained in six chapters of the dissertation. The analysis is based on a mixed-method approach consisting of empirical fieldwork conducted in Kenya (2018-2021) as well as document and media information gathered from secondary sources. I conducted 120 expert and informal interviews, visited key field sites across Kenya (particularly in Nairobi, Nakuru and Baringo counties), and observed industry conferences and events. The findings from the fieldwork are complemented by results from the analysis relevant policy, regulatory and legal reports, and online media and archives.
Large-scale renewable energy infrastructures in Kenya are mainly driven by Kenya’s Vision 2030, an ambitious plan to transform Kenya into a newly industrializing, middle-income country. The Government of Kenya identifies energy as the critical enabler for unlocking these economic growth and industrialization visions. As result, the country’s energy sector has gone through processes of neoliberal reforms, including the privatization of previously public entities, private sector participation and devolution in energy sector governance and development. These changes have allowed for the involvement and participation of multifaceted actors and stakeholders at international, national, sub-national and community levels in the country’s energy sector development. The development of large-scale renewable energy projects in Kenya is governed by rules and processes of interactions and cross-scalar linkages among these various stakeholders, broadly classified in this dissertation as investors and communities. The various investor and community groups have different strategic roles, represent different interests and have divergent and sometimes conflicting expectations. The financing for these projects comes from public finances from international and national sources, as well as private equity finance from private firms and industries. Due to the capital-intensive and high-risk features of these projects, the highest percentage of financing for the projects comes from international development financial institutions in the forms of concessional loans, grants and mezzanine, and directed towards risk mitigation and market-readiness. Climate mitigation financing in the form of specialized funds and green bonds used for blended financing and carbon offsetting also play important catalytic roles in crowding-in investors, especially at the pre-completion phases of the projects. Due to the large and influential roles of the public sector financiers and the involvement of private developers and industries, processes of financialization are so far not observed in the financing landscape of large-scale renewable energy projects in Kenya.
The challenge in the development (‘future-making’) of these large-scale energy projects lies in connecting and balancing out the divergent ‘futures’ of the involved multi-actors. The divergent interests, aspirations and expectations among different investor and community groups lead to contestations and protests, which when escalated and left unmanaged can stop the progress of ‘future-making’ in this context. This is where cross-scalar consultations and negotiations among stakeholder groups become necessary. Investors are often faced with sustainability dilemmas and tensions as they attempt to simultaneously apply the sustainability triad (economic, social and environment) in LSRE projects development. Due to the complexities in managing this situation, the investors often implement these projects using a process of strategic selectivity, notwithstanding the existence of certain unresolved issues, especially regarding land and compensation. Given that most projects are pursued and advanced notwithstanding the existence of some unresolved issues (especially regarding land and compensation), national and international agencies and investors often implement Corporate Social Responsibility (CSR) infrastructure projects and activities, such as the provision of drinking water for people and their livestock in the communities, to smoothen relation with host communities. However, some of these endeavours fail to fully and sustainably address the socio-economic concerns of local communities, especially the project-affected persons (PAPs)
Das Hitzeschockprotein GRP78 als Biomarker für Diagnose und Prognose bei Patienten mit Koronarer Herzerkrankung
Get PDFDas Hitzeschockprotein Glucose-regulated-protein-78 (GRP78) hat einen entscheidenden Einfluss auf die Homöostase im endoplasmatischen Retikulum und ist maßgeblich an der Antwort auf Stress des endoplasmatischen Retikulums beteiligt. Dieser Stress steht nach neueren Erkenntnissen im Zusammenhang mit der Entwicklung einer KHK. Um den mutmaßlichen Zusammenhang zu untersuchen, wurde in dieser Promotionsstudie prospektiv die Serumkonzentration des Hitzeschockproteins GRP78 in 782 Patienten untersucht, die sich im Jahr 2020 im Universitätsklinikum Bonn einer Koronarangiographie unterzogen.
Dafür wurde zu Beginn der Koronarangiographie arterielles Blut der Patienten gewonnen und zu Serum verarbeitet. Anschließend erfolgte die Bestimmung der GRP78-Konzentrationen mittels einer Enzymimmunoassay-Untersuchung mit bekannten Standard¬konzentrationen und statistischen Verfahren.
Die ermittelten GRP78-Konzentrationen in diesem Kollektiv waren zwar zwischen verschiedenen Gruppen teils stark unterschiedlich, aber in ihrer Größenordnung insgesamt vergleichbar mit Ergebnissen aus anderen Studien. Es zeigte sich, dass Patienten, die an einer koronaren Herzerkrankung litten, durchschnittlich tatsächlich eine erhöhte Konzentration des GRP78 im Serum aufwiesen. Dabei bestand jedoch kein linearer Zusammenhang mit der Anzahl der betroffenen Koronarien.
Die rechtfertigende Indikation für die Koronarangiographie und besonders die Unterscheidung zwischen akutem und chronischem Leiden war nicht signifikant mit der GRP78-Konzentration assoziiert.
Darüber hinaus konnte für das GRP78 kein signifikanter Zusammenhang für die ungeplante Rehospitalisierung und die Überlebenszeit über ein Jahr gezeigt werden. Die Gesamtmortalität über ein Jahr war unabhängig von der GRP78-Konzentration, wenn man sie allein betrachtete. Unter Berücksichtigung von Confoundern zeigte sich jedoch für Patienten mit einer GRP78-Serumkonzentration oberhalb des Medians des Kollektivs ein protektiver Effekt durch das GRP78
Role of NLRP3-ASC inflammasomes on Glial Activation after mild Traumatic Brain lnjury
Get PDFMild traumatic brain injury (mTBI) is a major public health concern, yet its pathophysiology remains poorly defined. Using a controlled skull impact–mild closed head injury model, this study investigated the role of the NLRP3 inflammasome and its adaptor ASC in glial responses after mTBI. We found significant upregulation of NLRP3-related proteins, cleaved caspase-1, IL-1β, and TNF-α at 7 and especially 21 days post-injury. Immunohistochemistry revealed ASC aggregation and extracellular release in microglia, coinciding with hypertrophy, shrinkage, and giant-cell formation. Astrocytes displayed parallel morphological changes and direct interaction with ASC-positive microglia, suggesting ASC-mediated glial communication. NLRP3 or ASC knockout mice showed reduced inflammasome activation, cytokine release, and glial pathology, with ASC deficiency producing a stronger protective effect, implicating additional ASC-dependent inflammasomes. These findings highlight persistent inflammasome activation and glial remodeling as key mechanisms in mTBI pathology and provide a foundation for therapeutic strategies targeting the NLRP3–ASC axis.Leichte traumatische Hirnverletzungen (mTBI) stellen ein erhebliches Gesundheitsproblem dar, deren Pathophysiologie jedoch nur begrenzt verstanden ist. In dieser Arbeit wurde mit einem kontrollierten Schädelaufprall-Modell die Rolle des NLRP3-Inflammasoms und seines Adaptors ASC in glialen Reaktionen nach mTBI untersucht. Es zeigte sich eine deutliche Hochregulation von NLRP3-assoziierten Proteinen, gespaltenem Caspase-1, IL-1β und TNF-α besonders 21 Tage nach der Verletzung. Immunhistochemische Analysen belegten eine Aggregation und extrazelluläre Freisetzung von ASC in Mikroglia, verbunden mit Hypertrophie, Schrumpfung und Riesenzellbildung. Astrozyten zeigten parallele morphologische Veränderungen sowie Interaktionen mit ASC-positiven Mikroglia, was auf eine ASC-vermittelte gliale Kommunikation hinweist. NLRP3- oder ASC-Knockout-Mäuse wiesen eine reduzierte Inflammasom-Aktivierung, geringere Zytokinfreisetzung und abgeschwächte gliale Pathologien auf, wobei der Effekt bei ASC-Defizienz ausgeprägter war. Dies deutet auf die Beteiligung weiterer ASC-abhängiger Inflammasome hin. Insgesamt verdeutlichen die Ergebnisse, dass eine persistente Inflammasom-Aktivierung und gliales Remodeling zentrale Mechanismen der mTBI-Pathologie darstellen und eine Grundlage für zukünftige therapeutische Ansätze bilden, die auf die NLRP3–ASC-Achse abzielen
Die Zeit des Zweiten Weltkriegs in den Schulbüchern sechs arabischer Länder, Irans und der Türkei seit 1950
Get PDFSeit fast achtzig Jahren beschäftigt der arabisch-israelische Konflikt die Welt. Dabei unterscheiden sich die heutigen Debatten nicht wesentlich von denen der fünfziger Jahre: Ist eine Zweistaatenlösung zum Greifen nah oder liegt sie in weiter Ferne? Während sich die Berichterstattung oft nur mit den vordergründigen Ereignissen beschäftigt, bleiben die tiefer liegenden Ursachen meist im Dunkeln. Worauf aber beruht dieses scheinbar "ewige Problem"? Gibt es einen Zusammenhang zwischen seiner "Unlösbarkeit" und der in der arabisch-islamischen Welt häufig anzutreffenden Verehrung Adolf Hitlers?
Der Frage, welches Wissen über den Zweiten Weltkrieg, den Nationalsozialismus und den Holocaust im Nahen Osten vorhanden ist, geht diese Arbeit nach. Hierzu wurden offizielle Schulbuchtexte der Länder Ägypten, Syrien, Irak, Jordanien, Saudi-Arabien, Tunesien, Iran und Türkei zwischen 1950 und der Gegenwart ausgewertet und inhaltlich geordnet. Die thematisch strukturierte Präsentation der übersetzten originalen Quellen ermöglicht es dem Leser, sich selbst ein Urteil über die historische Sichtweise der jeweils Verantwortlichen zu bilden.
Die Untersuchung bietet aufschlussreiche Einblicke nicht nur hinsichtlich deutscher Geschichte, sondern auch in Bezug auf die untersuchten Staaten selbst und ihre Verortung im historischen Kontext. Zusammenfassend kann gesagt werden, dass die meisten Unterrichtsmaterialien ein großes Interesse am Zweiten Weltkrieg wie auch am deutschen Nationalsozialismus haben, die Einordnung und Beurteilung der Ereignisse aber von Land zu Land stark variiert. Anders verhält es sich mit dem Holocaust: Die Judenvernichtung wird in ihrem Ausmaß von allen Schulbüchern verschwiegen, kommt eine Diskriminierung zur Sprache, so dient sie dazu, den Juden selbst die Schuld an ihrer Verfolgung zu geben.
Eine längst überfällige Studie angesichts der politischen Brisanz des Themas.The Arab-Israeli conflict has engaged the world for almost eighty years. Yet today's debates are not significantly different from those of the 1950s:
Is a two-state solution within reach or is it still a distant prospect? While media coverage often focuses only on superficial events, the underlying causes usually remain obscure. But what is the cause of this seemingly "eternal problem"? Is there a connection between its "insolubility" and the veneration of Adolf Hitler that is often found in the Arab-Islamic world?
This thesis askes and explores what knowledge about World War II, National Socialism, and the Holocaust existing in the Middle East. To this end, official school textbooks from Egypt, Syria, Iraq, Jordan, Saudi Arabia, Tunisia, Iran, and Turkey in use between 1950 and the present were evaluated and organized by content. A thematically structured presentation of the translated original sources enables readers to form their own opinion about the historical perspective of those responsible.
The study offers illuminating perspectives not only on German history, but also on the countries thus examined and their place in the historical context. To summarize, it can be said that most teaching materials show a keen interest in World War II and German National Socialism, but the classification and assessment of events varies greatly from country to country. The situation is different with regard to the Holocaust: The extent of the exter-mination of the Jews is concealed in all school textbooks, and if discrimination is mentioned, blame for their persecution is put on the Jews themselves.
Given the topic's political sensitivity, this study is long overdue