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Isolation und Testung von rekombinanten Galektinen zur Prophylaxe der proliferativen Vitreoretinopathie
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Medizinalchemische Entwicklung von allosterischen Modulatoren für den nikotinischen Acetylcholinrezeptor zur Behandlung von Nervenkampfstoffvergiftungen
Get PDFVergleich und Charakterisierung zweier retroviraler KMT2A::MLLT1-Konstrukte mit und ohne intronischer Sequenz im Translokationsbereich
Get PDFOn the role of pre-pulses in laser-irradiation of isolated micro-spheres at relativistic intensities
Get PDFThe acceleration of particle in a plasma driven by an ultra-intense laser pulse holds promise to power the next generation of particle accelerators. A key element hereby is the target onto which the laser pulse is focused and from which the ions are accelerated. In particular isolated mass-limited targets with a size smaller than the laser focus can achieve highly efficient volumetric acceleration regimes.
In this thesis the effect of pre-pulses on the plasma properties just before the beginning of the acceleration process is investigated. Motivated by previous work at multiple national and international research facilities, experiments were performed at the ATLAS-3000 laser at CALA. The goal of these experiments was to determine whether a temporal laser contrast with a short pre-pulse and moderately long and intense rising edge before the main pulse is sufficient and possibly even beneficial for proton acceleration from isolated polystyrene micro-spheres. From the analysis of the transmitted laser light the position of the target with respect to the laser focus was reconstructed. As this reveals a systematic displacement of the target to areas of lower intensity, the interpretation of the results is ambiguous and requires further investigation. To this end a simple model was developed, which can be solved numerically to calculate the target conditions at the time of the main pulse from the experimental laser contrast. This model was compared to detailed radio-hydrodynamic simulations for verification. While the simulations reveal some features which are not included in the model, such as a prominent shock wave traveling through the target, the agreement on averaged densities and temperatures is remarkable.
Informed by the model and simulations, it is concluded that the experimentally observed offset between laser focus and target is due to systematic errors. The temporal contrast of the ATLAS-3000 is in fact expected to result in near-ideal conditions for proton acceleration from these targets. Further, the model is applied to other laser systems and general limits on the laser contrast for efficient acceleration from isolated targets are extracted.Die Beschleunigung von Teilchen in einem Plasma, durch einen ultrastarken Laserpuls, soll die nächste Generation von Teilchenbeschleunigern antreiben. Ein Schlüsselelement hierbei ist das Target, auf das der Laserpuls fokussiert wird und in dem die Ionen beschleunigt werden. Insbesondere isolierte massenlimitierte Targets mit einer Größe kleiner als der Laserfokus können hoch effiziente volumetrische Beschleunigungsregime erreichen.
In dieser Arbeit wird der Effekt von Vorpulsen auf die Plasmabedingungen kurz vor Beginn des Beschleunigungsprozesses untersucht. Motiviert durch frühere Arbeiten an verschiedenen nationalen und internationalen Forschungszentren wurden Experimente am ATLAS-3000 Laser in CALA durchgeführt. Ziel dieser Experimente war es festzustellen, ob ein zeitlicher Laser-Kontrast mit einem kurzen Vorpuls und einer moderat langen und intensiven ansteigenden Flanke vor dem Hauptpuls ausreichend und möglicherweise sogar vorteilhaft für die Beschleunigung von Protonen aus isolierten Polystyrol-Mikrokugeln ist. Durch die Analyse des transmittierten Laserlichts wurde die Position des Targets relativ zum Laserfokus rekonstruiert. Da dies eine systematische Verschiebung des Targets zu Bereichen niedrigerer Intensität offenbart, ist die Interpretation der Ergebnisse mehrdeutig und erfordert weitere Untersuchungen.
Zu diesem Zweck wurde ein einfaches Modell entwickelt, das numerisch gelöst werden kann, um die Plasmabedingungen zum Zeitpunkt des Hauptpulses aus dem experimentellen Laser-Kontrast zu berechnen. Dieses Modell wurde zur Verifizierung mit detaillierten radio-hydrodynamischen Simulationen verglichen. Während die Simulationen einige Merkmale offenbaren, die nicht im Modell enthalten sind, wie zum Beispiel eine prominente Schockwelle, die durch das Target propagiert, ist die Übereinstimmung bei gemittelten Dichten und Temperaturen bemerkenswert.
Auf Grundlage des Modells und der Simulationen wird geschlossen, dass die experimentell beobachtete Verschiebung zwischen Laserfokus und Target auf systematische Fehler zurückzuführen ist und der zeitliche Kontrast des ATLAS-3000 nahezu ideal zur Beschleunigung von Protonen aus diesen Targets geeignet ist. Weiterhin wird das Modell auf andere Lasersysteme angewandt und allgemeine Grenzen für den Laser-Kontrast für effiziente Beschleunigung aus isolierten Zielen werden extrahiert
Potential of interleukin-6 in cerebrospinal fluid for diagnosing EVD-associated ventriculitis in patients with subarachnoid hemorrhage, intracerebral hemorrhage or traumatic brain injury
Get PDFSocial contracts for adaptation to climate change
Get PDFAdaptation to the impacts of climate change is becoming increasingly urgent and challenging. Meeting the stark challenges of adaptation will require collective efforts from different actors of society (state, civil society, individuals, private sector, etc.), ideally with a shared understanding of adaptation goals and visions and a clear, agreed-upon distribution of roles and responsibilities. However, in reality, adaptation often occurs in a socially contested arena, characterized by multi-actor constellations with potentially diverging viewpoints on what different actors envision and expect in terms of adaptation priorities and the distribution of roles and responsibilities for adaptation. An urgent requirement to advance adaptation efforts is the need for coherent social contracts where actors ideally agree or find an arrangement, despite conflicting perspectives.
Despite the growing scientific research on adaptation, several gaps could be observed in the conceptual, theoretical, empirical, and methodological debates on understanding and assessing social contracts for adaptation in the current literature. Although previous literature has established the potential usefulness of a social contracts lens to adaptation debates, detailed conceptual and theoretical understanding in the adaptation context is largely lacking to date. Further, empirical evidence and conceptual literature on actors’ desired adaptation objectives and perceived distributions of roles and responsibilities have received some attention yet remain under-researched and often without an explicit social contracts lens. Given such perspectives' tacit and implicit nature, a related methodological challenge is the difficulty in capturing actors’ diverse viewpoints. A significant step toward achieving coherent social contracts for adaptation is understanding how different actors perceive and evaluate their solution spaces for adaptation in a multi-dimensional fashion, which has not received sufficient attention in the literature.
The above-identified gaps are most starkly illustrated in cities and urban areas, especially in countries with emerging markets, that are situated at the confluence of being on the frontlines of climate risk globally, faced with high adaptation pressure, changing patterns of social, economic, and demographic growth but at the same time also seen as frontrunners and role models of countries and regions. Mumbai, the financial capital of India, ranks among the top cities at risk of coastal flooding and the impact of rising sea levels in current and future rankings. The city is characterized by some of the heaviest adaptation challenges that one can find globally, along with stark inequalities, with almost half the population living in slums on the one end and a powerful elite on the other, with a growing aspirational middle class in between. Hence, the study draws on flood risk management in Mumbai, considered a highly relevant and important empirical case.
The study presented here aims to address the above-identified research gaps and adopts a three-fold objective. First, it seeks to advance the conceptual understanding of social contracts for adaptation by providing a framework to guide their assessment. Second, it aims to empirically assess how different actors perceive and evaluate adaptation solution spaces for their desirability and feasibility in a multi-dimensional fashion. Further, the study assesses actors’ desired adaptation objectives and expectations on the distribution of roles and responsibilities for adaptation to flood risk in Mumbai. Finally, in methodological terms, it aims to explore the potential of using social listening on Twitter to assess social contracts for adaptation in cities and other societal contexts.
Against this background, the study adopts a mixed methods approach and combines inductive exploration of the data with the deductive application of a social contracts theoretical lens. The study develops the approach of social listening using Twitter data to capture actors’ diverse viewpoints on adaptation priorities and expectations of roles and responsibilities for flood risk management in Mumbai, given that social media platforms are becoming increasingly important arenas of exchange. This involved collecting all flood-risk-related Tweets over four months of the monsoon season 2021 (ca. 70,000 Tweets), which were subsequently filtered for their dominance and analyzed. These findings are triangulated with semi-structured expert interviews conducted with key stakeholders across the state, civil society, and academic actors from Mumbai and field-based participant observation at workshops and meetings. The initially planned household survey had to be postponed due to the pandemic that heavily influenced the research design of this study.
Guided by the conceptual lens of social contracts and the mixed-methods approach, the study draws on the empirical analysis of flood risk management in Mumbai. The findings from the multi-dimensional evaluation of perceived solution spaces for adaptation revealed significant mismatches between state and non-state actors’ perceptions of desirability and the evaluation of the feasibility of different adaptation options. Overall, institutional changes and the pivotal role of institutional dimensions were most strongly identified, especially by non-state actors. At the same time, the starkest disparities were found between state and non-state actors on physical infrastructure measures. In operationalizing the conceptual framework of social contracts for adaptation, the study found surprisingly wide gaps and large contestations in the adaptation debates in Mumbai in two respects: between different actors and between what actors envisioned, observed in reality, and perceived as legally defined. Diverging viewpoints on actors’ desired adaptation objectives and target actors could be observed as well as strong rifts in the distribution of roles and responsibilities. In addition to the diverging perspectives, the findings also showed ambiguity in both regards, where actors did not clearly articulate their views. Social listening on Twitter allowed to capture actors' unsolicited, implicit, and tacit viewpoints in a large N sample in almost real-time. Further, the qualitative sentiment analysis proved to be a helpful entry point for understanding the gaps between actors’ viewpoints and expectations.
The study could make an empirical and analytical contribution to advance current feasibility assessments of adaptation options by including an actor-specific lens, distinguishing desirability from feasibility, and applying it to real-world settings. An explicit focus on actors’ desired adaptation objectives and target actors and the contestations revealed through the empirical findings emphasize the importance of assessing and aligning actors’ underlying priorities in negotiating the process of forming coherent social contracts for adaptation. The findings suggest aligning actors’ desired adaptation objectives as a first step toward shaping coherent social contracts for adaptation. Rifts and ambiguities in actors’ perceptions of who is or should be responsible for what tasks in adapting ultimately have severe implications on the distribution of burdens. These questions become critical when existing risk management regimes start to approach their limits not only in light of the changing feasibility or effectiveness of adaptation options but also in the face of evolving priorities in rapidly growing economies and aspirational societies such as India. The study's most novel contribution lies in its methodological development of social listening on Twitter to assess gaps in social contracts for adaptation. The study could contribute to the conceptual, empirical, and methodological realms of scientific knowledge on social contracts for adaptation and propose several questions for future research
Identifizierung der sekundären vestibulo-okulären Neurone beim Menschen und deren Tau-Pathologie in unterschiedlichen Stadien bei Fällen mit progressiver supranukleärer Parese (PSP)
Get PDFDie Bedeutung des oralen Mikrobioms im Zusammenspiel mit der Immunantwort in der Kieferorthopädie unter Berücksichtigung von Risikofaktoren für orale Dysbiosen und biomechanischen Aspekten
Get PDFStress und Resilienz im Zahnmedizinstudium
Get PDFTheoretischer Hintergrund: Psychische Gesundheit und Stress gelten als Trends der heutigen Gesellschaft und gewinnen insbesondere im Bereich Prävention zunehmend an Bewusstsein. Resilienz gilt als Fähigkeit, trotz außerordentlicher Stresssituationen, die eigene Gesundheit hochzuhalten bzw. sich nach Belastungsphasen schnell zu erholen. Unterschiede zwischen Berufsgruppen im Stress- und Gesundheitserleben werden immer wieder deutlich, wobei Personen im Gesundheitssektor besonders belastet erscheinen und der Bedarf an Interventionsmaßnahmen entsprechend groß ist. Dabei werden Zahnmediziner bislang selten separat untersucht und wenn doch, dann zeigen sie im Vergleich zu Humanmedizinern sogar oft die höheren Stressanfälligkeiten.(2) In einer der vorliegenden Arbeit vorausgehenden Befragung an der LMU Zahnklinik wurden Spezifika im Stresserleben bei Zahnmedizinstudierenden identifiziert. Diese sollen in einem angepassten Resilienztraining für Zahnmediziner konzeptionell aufgegriffen werden. Schließlich soll die Effektivität dieses Trainings als gesundheitliche Präventionsmaßnahme untersucht werden. Perspektivisch steht zur Diskussion, diese oder ähnliche Maßnahmen in Form von Wahlfächern nachhaltig ins zahnmedizinische Curriculum aufzunehmen.
Methodik: Das „Resilienztraining für Studierende der Medizin, Ärzte und Gesundheitsfachpersonal“(1) wurde anhand von fachspezifischen Stressoren für Zahnmedizinstudierende angepasst. Das Training wurde ab dem Sommersemester 2021 bis zum Wintersemester 2022/23 als freiwillige Blockveranstaltung an mehreren Wochenenden im Semesterverlauf angeboten (online mit der Videokonferenzsoftware „Zoom“). Nach jedem Trainingsdurchlauf wurde qualitatives Feedback von den Teilnehmenden eingeholt und als Prozessevaluation in das Konzept der weiteren Trainings eingearbeitet.
Für die Effektevaluation wurden Datenerhebungen Prä- und Post-Training durchgeführt und als sechsmonatige Längsschnittstudie analysiert, wobei ein besonderer Fokus auf die Resilienzentwicklung, das allgemeine Gesundheitsverhalten, sowie das subjektive Stresserleben gelegt wurde. Der für die Messung genutzte Fragebogen besteht als Testbatterie aus dem STQL-S (Fragebogen zur Stressbewältigung und Lebensqualität im Studium)(3) und der deutschsprachigen 10-Item Version der CD-RISC (Connor-Davidson Resilience Scale)(4). Die Prä- und Post-Trainingsdaten von Teilnehmenden wurden anhand persönlicher Passwörter gepaart, und mit Daten von Befragten verglichen, die an keinem Resilienztraining teilgenommen haben. Insgesamt fanden acht Befragungen über einen Zeitraum von 21 Monaten vom April 2021 bis Dezember 2022 statt. Neben der Längsschnittanalyse wurden alle primären Datenfälle auch als Querschnittsanalyse beleuchtet. Dabei wurde eine Aufteilung zwischen den Geschlechtern und dem Studienfortschritt vorgenommen. Für die statistische Auswertung wurden sowohl deskriptive als auch schließende, parametrische Verfahren genutzt. Die Analyse erfolgte mittels der Software IBM SPSS Statistics, Version 28 und 29.
Ergebnisse: Die erhobenen Daten zeigten nach schließender statistischer Auswertung, dass das angepasste Resilienztraining positiv assoziiert mit einer gesteigerten Resilienz von teilnehmenden Zahnmedizinstudierenden (Interventionsgruppe) ist (Interaktion zwischen der Zeit (T1 und T2) und den Untersuchungsgruppen (Interventions- und Vergleichsgruppe): Sphärizität angenommen F(1,54) = 4,93, p = 0,031, also p < 0,05, partielles η² = 0,084 (Mittlerer Effekt(5)). Zudem zeigte die Interventionsgruppe eine signifikante Minderung im subjektiven Stresserleben, sowie eine Steigerung in der allgemeinen Zufriedenheit. Qualitativ wurde gezeigt, dass das Resilienztraining eine geeignete Maßnahme darstellt, den sozialen Austausch hinsichtlich des psychischen Wohlergehens bei Zahnmedizinstudierenden zu stärken. Veränderungen im körperlichen Gesundheitsverhalten waren vielseitig und konnten nicht eindeutig im Zusammenhang mit dem Resilienztraining begründet werden.
Weiterhin konnte eine positive Entwicklung der Resilienz und Zufriedenheit, sowie eine negative Entwicklung des Stresserlebens zwischen Studierenden der vorklinischen Semester und fortgeschritteneren Studierenden der klinischen Semester dargestellt werden. Im Geschlechtervergleich zeigten sich die Frauen deutlich weniger resilient, stärker gestresst und ähnlich zufrieden wie die befragten Männer.
Diskussion: Die Ergebnisse zeigen, dass das angepasste Resilienztraining eine geeignete Präventionsmaßnahme für die psychische Gesundheit Zahnmedizinstudierender darstellt. Trotzdem birgt die vorliegende Arbeit einige Limitationen, welche in weitergehenden Untersuchungen reduziert werden sollten. Die Verstetigung des Trainingsangebots als Wahlfach im Rahmen der Umstrukturierung des Zahnmedizinstudiums sollte weiterverfolgt werden. Eine Übertragbarkeit des Projekts auf andere zahnmedizinische Standorte ist denkbar.Background: Mental health and stress are recognized trends in modern society, particularly gaining awareness in the realm of prevention. Resilience is acknowledged as the capacity to maintain one's health despite extraordinary stress situations or to recover quickly after peri-ods of strain. Disparities in stress and health experiences among professional groups are ev-ident, with individuals in the healthcare sector appearing particularly burdened, emphasizing the need for intervention measures. Dental practitioners have been infrequently studied separately, and when examined, they often exhibit higher susceptibility to stress compared to medical doctors.(2) Specificities in stress experiences among dental students were identified in a preceding survey conducted at the LMU Dental Clinic. These are to be conceptually addressed in an adapted resilience training program for dental practitioners. Finally, the effectiveness of this training as a health prevention measure is to be investigated. Perspectives include discussing the integration of such measures sustainably into the dental curriculum, e.g. in the form of elective courses.
Methodology: The "Resilience training for health care professionals and medical students"(1) was tailored based on specific stressors for dental students. The training was offered as a voluntary block event on several weekends throughout the semester, from the summer semester of 2021 to the winter semester of 2022/23 (online using the video conferencing software "Zoom"). Qualitative feedback was obtained from participants after each training session and incorporated into the concept of subsequent trainings as process evaluation. For the effects evaluation, data collection was conducted pre- and post-training and analyzed as a six-month longitudinal study, with a particular focus on resilience development, general health behavior, and subjective stress experiences. The measurement instrument utilized was a test battery comprising the STQL-S (Questionnaire on Stress Coping and Quality of Life in Studies)(3) and the German-language 10-Item version of the CD-RISC (Connor-Davidson Resili-ence Scale)(4). Pre- and post-training data from participants were paired using personal passwords and compared with data from respondents who did not participate in resilience training. Overall, eight surveys were conducted over a period of 21 months from April 2021 to December 2022. In addition to the longitudinal analysis, all primary data cases were also examined as cross-sectional analysis, with a division between genders and academic progress. Statistical analysis involved descriptive and inferential parametric methods, conducted using IBM SPSS Statistics, Version 28 and 29.
Results: The collected data, after conclusive statistical analysis, demonstrated that the adapted resilience training was positively associated with increased resilience among participating dental students (intervention group) (interaction between time (T1 and T2) and study groups (intervention and comparison group): assuming sphericity F(1, 54) = 4.93, p = 0.031, hence p < 0.05, partial η2 = 0.084 (medium effect(5)). Additionally, the intervention group showed a significant reduction in subjective stress experiences and an increase in overall satisfaction. Qualitatively, it was demonstrated that resilience training represents a suitable measure to enhance social exchange regarding the psychological well-being of dental students. Changes in physical health behavior were diverse and could not be unequivocally attributed to resilience training. Furthermore, a positive development in resilience and satisfaction, as well as a negative trend in stress experiences, was observed between students in preclinical and advanced clinical semesters. In gender comparison, women exhibited significantly less resilience, higher stress levels, and similar satisfaction levels to the surveyed men.
Discussion: The results demonstrate that the adapted resilience training constitutes a suitable preventive measure for the mental health of dental students. Nevertheless, the present study entails certain limitations that should be reduced in further investigations. The continuation of the training offer as an elective course within the restructuring of dental education should be pursued. The project's transferability to other dental sites is conceivable