@phdthesis{Djakowski2024, author = {Djakowski, Paul}, title = {Schulische politische Bildung in Deutschland und Polen. Eine kompetenzbasierte komparative Analyse der Leitf{\"a}cher f{\"u}r politische Bildung anhand von Stundentafeln und Curricula allgemeinbildender staatlicher Schulformen der Primarstufe sowie der Sekundarstufen I und II im Schuljahr 2019/20}, publisher = {W{\"u}rzburg University Press}, address = {W{\"u}rzburg}, isbn = {978-3-95826-230-0}, doi = {10.25972/WUP-978-3-95826-231-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-326799}, school = {W{\"u}rzburg University Press}, pages = {XXI, 593}, year = {2024}, abstract = {Politische Bildung {\"u}bt nicht nur einen großen Einfluss auf die zuk{\"u}nftige Konstellation des politischen Systems aus, sondern beeinflusst ebenfalls das soziale Miteinander pr{\"a}gend. Damit werden entscheidende Weichen f{\"u}r die Entwicklung der Gesellschaft, der Nation und des Staates gestellt. Im Zuge dieses Prozesses durchl{\"a}uft jeder junge B{\"u}rger einen politischen Bildungsweg an Schulen. Die Vorgaben dar{\"u}ber, wie schulische politische Bildung auszusehen hat und welche Kompetenzen Sch{\"u}ler in diesem Zusammenhang erwerben sollen, geben die Kultus- bzw. Bildungsministerien in Curricula vor, verbindlich f{\"u}r alle Lehrer. Durch eine komparative Analyse der Curricula kann damit eindeutig die staatlich vorgegebene politische, gesellschaftliche und soziale Richtung festgestellt werden, die junge Menschen einschlagen sollen. Welche edukativen Ziele der politischen Bildung werden verfolgt? Was sollen Sch{\"u}ler lernen, um mit diesen Kompetenzen die Zukunft ihres Kollektivs zu gestalten? Wo liegen die Gemeinsamkeiten und Unterschiede zweier Staaten, in unserem Fall Deutschlands und Polens, im Hinblick auf die schulische politische Bildung? Beantwortet werden diese Fragestellungen durch das Anwenden zweier Methoden der qualitativen Sozialforschung, der komparativen Inhaltsanalyse, zum einen der strukturierenden zum anderen der induktiven. Davor erfolgt eine komparativ quantitative Untersuchung, die den Umfang der Unterrichtszeit in den Leitf{\"a}chern f{\"u}r politische Bildung in allen Bundesl{\"a}ndern und in Polen vergleicht, was einer empirischen Totalerhebung der komplex umfangreichen Daten entspricht. Die quantitativen Forschungsergebnisse zeigen deutliche Differenzen zwischen Deutschland und Polen, in einem der beiden Staaten wird signifikant mehr Zeit f{\"u}r politische Bildung im Leitfach dieser Disziplin investiert als im anderen. Anhand der qualitativen Daten ist zu erkennen, dass einerseits eine gemeinsame Grundbasis von Kompetenzen der politischen Bildung zwischen Deutschland und Polen besteht. Anderseits stechen in beiden L{\"a}ndern eindeutige Unterschiede hervor, deren Ursprung zum einen historische Erfahrungen der Nationen und Staaten abbildet, zum anderen aktuell gegens{\"a}tzliche politische Interessen untermauert.}, subject = {Politische Bildung}, language = {de} } @phdthesis{Hartmann2024, author = {Hartmann, Oliver}, title = {Development of somatic modified mouse models of Non-Small cell lung cancer}, doi = {10.25972/OPUS-36340}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-363401}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {In 2020, cancer was the leading cause of death worldwide, accounting for nearly 10 million deaths. Lung cancer was the most common cancer, with 2.21 million cases per year in both sexes. This non-homogeneous disease is further subdivided into small cell lung cancer (SCLC, 15\%) and non-small cell lung cancer (NSCLC, 85\%). By 2023, the American Cancer Society estimates that NSCLC will account for 13\% of all new cancer cases and 21\% of all estimated cancer deaths. In recent years, the treatment of patients with NSCLC has improved with the development of new therapeutic interventions and the advent of targeted and personalised therapies. However, these advances have only marginally improved the five-year survival rate, which remains alarmingly low for patients with NSCLC. This observation highlights the importance of having more appropriate experimental and preclinical models to recapitulate, identify and test novel susceptibilities in NSCLC. In recent years, the Trp53fl/fl KRaslsl-G12D/wt mouse model developed by Tuveson, Jacks and Berns has been the main in vivo model used to study NSCLC. This model mimics ADC and SCC to a certain extent. However, it is limited in its ability to reflect the genetic complexity of NSCLC. In this work, we use CRISPR/Cas9 genome editing with targeted mutagenesis and gene deletions to recapitulate the conditional model. By comparing the Trp53fl/fl KRaslsl- G12D/wt with the CRISPR-mediated Trp53mut KRasG12D, we demonstrated that both showed no differences in histopathological features, morphology, and marker expression. Furthermore, next-generation sequencing revealed a very high similarity in their transcriptional profile. Adeno-associated virus-mediated tumour induction and the modular design of the viral vector allow us to introduce additional mutations in a timely manner. CRISPR-mediated mutation of commonly mutated tumour suppressors in NSCLC reliably recapitulated the phenotypes described in patients in the animal model. Lastly, the dual viral approach could induce the formation of lung tumours not only in constitutive Cas9 expressing animals, but also in wildtype animals. Thus, the implementation of CRISPR genome editing can rapidly advance the repertoire of in vivo models for NSCLC research. Furthermore, it can reduce the necessity of extensive breeding.}, subject = {CRISPR/Cas-Methode}, language = {en} } @phdthesis{Schwenkert2024, author = {Schwenkert, Marc}, title = {Zwei Burschenschafter als B{\"u}rgermeister im Dritten Reich. Theo Memmel in W{\"u}rzburg und Paul May in Halle im Vergleich.}, doi = {10.25972/OPUS-36096}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-360966}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {In der Dissertation „Zwei Burschenschafter als B{\"u}rgermeister im Dritten Reich. Theo Memmel in W{\"u}rzburg und Paul May in Halle im Vergleich." steht die Untersuchung der Lebenswege der beiden Wahlbeamten Dr. Paul May und Theodor Memmel anhand ihrer Biographien im Fokus. May glitt dank seiner sich stetig erweiternden Fachkenntnisse sowie seiner Anpassungsf{\"a}higkeit durchweg in Leistungspositionen problemlos durch vier politische Systeme - vom Kaiserreich bis zur DDR. Seiner b{\"u}rgerlichen politischen Ausrichtung blieb er hierbei stets treu. Memmel hingegen machte bedingt durch seine an-dere und gravierendere Weltkriegserfahrung einen Prozess vom politisch des-interessierten Front- und Freikorpsk{\"a}mpfer {\"u}ber die Bayerische Volkspartei hin zum {\"u}berzeugten Nationalsozialisten. Nach dem Untergang des Dritten Reichs stand er vor dem Nichts, sowohl in beruflicher als auch in politischer Hinsicht. In seiner Studentenverbindung fand er jedoch einen Raum, in dem er sich engagieren und Anerkennung finden konnte. Da May und Memmel durch ihre gemeinsame studentische Korporation gleich sozialisiert wurden und sie sich auf unterschiedliche Weise wie ein ro-ter Faden durch ihr Leben zog, erfuhr diese ebenfalls eine Untersuchung. Hierbei ergab sich, dass die Wandlung von der toleranten Progressverbindung Adelphia zur pflichtschlagenden Burschenschaft in der Deutschen Burschen-schaft im Jahr 1933 keinen pl{\"o}tzlichen Bruch darstellte, sondern vielmehr die Folge einer langj{\"a}hrigen Entwicklung war, wobei der Erste Weltkrieg als be-sonders einschneidender Faktor zu bewerten ist. Am letztendlichen Art- und Dachverbandswechsel hatte auch Memmel einen entscheidenden Anteil. Dass nach der Umwandlung der waffenstudentischen Verbindungen in NS-Kameradschaften diese (auch Adelphia) w{\"a}hrend des Zweiten Weltkriegs teil-weise in W{\"u}rzburg im Verborgenen wiedererstehen konnten, hing auch mit der Patronage durch Memmel und sein imposantes Netzwerk zusammen. Den dritten Untersuchungskomplex dieser Arbeit bildet die kommunale Entwicklung von Groß- und Gauhauptst{\"a}dten im Dritten Reich, da sowohl W{\"u}rzburg als auch Halle eine solche verk{\"o}rperten. Ein Vergleich mit anderen St{\"a}dten unter denselben Voraussetzungen l{\"a}sst darauf schließen: Wer 1933/34 Oberb{\"u}rgermeister einer Groß- und Gauhauptstadt wurde, verdank-te dies nicht seiner Qualifikation. Die Nationalsozialisten, die dieses Amt er-hielten, bem{\"u}hten sich noch nicht einmal darum, es zu bekommen. Vielmehr stellten sie einen Kompromiss aus den jeweiligen lokalen Macht- und Interes-senskonstellationen dar. Eine Ausnahme hiervon bilden nur die wenigen St{\"a}dte, in denen bereits vor 1933 ein NSDAP-Angeh{\"o}riger als Stadtoberhaupt kandidiert hatte. Der Status der Gauhauptstadt f{\"u}hrte f{\"u}r die jeweiligen Oberb{\"u}rgermeister zu einem ganz besonderen Unterstellungsverh{\"a}ltnis, das sich als zweiseitiges Schwert entpuppte: Einerseits erhielt ihre Kommune spezielle F{\"o}rderung, andererseits standen sie unter einem hohem Erwar-tungsdruck, der sich vielerorts in einem schlechten Verh{\"a}ltnis von Oberb{\"u}r-germeister und Gauleiter manifestierte. Das Oberb{\"u}rgermeisteramt im Drit-ten Reich stellte aus beruflicher Sicht einen doppelten Bruch mit der Zeit vor 1933 dar: Zum einen konnte man ohne die bis dahin {\"u}blichen Qualifikationen zum Wahlbeamten einer Großstadt aufsteigen, andererseits bedeutete dies auch gleichzeitig das Karriereende.}, subject = {Geschichte}, language = {de} } @phdthesis{Birke2024, author = {Birke, Claudius B.}, title = {Low Mach and Well-Balanced Numerical Methods for Compressible Euler and Ideal MHD Equations with Gravity}, doi = {10.25972/OPUS-36330}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-363303}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Physical regimes characterized by low Mach numbers and steep stratifications pose severe challenges to standard finite volume methods. We present three new methods specifically designed to navigate these challenges by being both low Mach compliant and well-balanced. These properties are crucial for numerical methods to efficiently and accurately compute solutions in the regimes considered. First, we concentrate on the construction of an approximate Riemann solver within Godunov-type finite volume methods. A new relaxation system gives rise to a two-speed relaxation solver for the Euler equations with gravity. Derived from fundamental mathematical principles, this solver reduces the artificial dissipation in the subsonic regime and preserves hydrostatic equilibria. The solver is particularly stable as it satisfies a discrete entropy inequality, preserves positivity of density and internal energy, and suppresses checkerboard modes. The second scheme is designed to solve the equations of ideal MHD and combines different approaches. In order to deal with low Mach numbers, it makes use of a low-dissipation version of the HLLD solver and a partially implicit time discretization to relax the CFL time step constraint. A Deviation Well-Balancing method is employed to preserve a priori known magnetohydrostatic equilibria and thereby reduces the magnitude of spatial discretization errors in strongly stratified setups. The third scheme relies on an IMEX approach based on a splitting of the MHD equations. The slow scale part of the system is discretized by a time-explicit Godunov-type method, whereas the fast scale part is discretized implicitly by central finite differences. Numerical dissipation terms and CFL time step restriction of the method depend solely on the slow waves of the explicit part, making the method particularly suited for subsonic regimes. Deviation Well-Balancing ensures the preservation of a priori known magnetohydrostatic equilibria. The three schemes are applied to various numerical experiments for the compressible Euler and ideal MHD equations, demonstrating their ability to accurately simulate flows in regimes with low Mach numbers and strong stratification even on coarse grids.}, subject = {Magnetohydrodynamik}, language = {en} } @phdthesis{Krings2024, author = {Krings, Moritz}, title = {Universit{\"a}re Psychiatrie um 1900 : Die Anfangsjahre der psychiatrischen Klinik in W{\"u}rzburg}, doi = {10.25972/OPUS-36140}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-361407}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Ende des 19. Jahrhunderts standen sich in Deutschland zwei verschiedene Arten psychiatrischer Institutionen gegen{\"u}ber, die Anstaltspsychiatrien auf der einen, die universit{\"a}ren psychiatrischen Kliniken auf der anderen Seite. Die psychiatriehistorische Forschung widmete sich {\"u}berwiegend psychiatrischen Anstalten w{\"a}hrend Kliniken hier unterrepr{\"a}sentiert sind. Die vorliegende Arbeit m{\"o}chte zur historischen Kenntnis universit{\"a}rer psychiatrischer Einrichtungen beitragen. Hierzu werden die Charakteristika einer psychiatrischen Klinik um 1900 anhand des Beispiels der psychiatrischen Klinik der Universit{\"a}t W{\"u}rzburg betrachtet. Der Fokus liegt hierbei neben Lage und Aufbau der Klinik sowie deren Personal auf den drei Bereichen Patient*innen, Forschung und Lehre.}, subject = {Julius-Maximilians-Universit{\"a}t W{\"u}rzburg}, language = {de} } @phdthesis{Ramirez2024, author = {Ramirez, Yesid A.}, title = {Structural basis of ubiquitin recognition and rational design of novel covalent inhibitors targeting Cdu1 from \(Chlamydia\) \(Trachomatis\)}, doi = {10.25972/OPUS-19168}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-191683}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {The WHO-designated neglected-disease pathogen Chlamydia trachomatis (CT) is a gram-negative bacterium responsible for the most frequently diagnosed sexually transmitted infection worldwide. CT infections can lead to infertility, blindness and reactive arthritis, among others. CT acts as an infectious agent by its ability to evade the immune response of its host, which includes the impairment of the NF-κB mediated inflammatory response and the Mcl1 pro-apoptotic pathway through its deubiquitylating, deneddylating and transacetylating enzyme ChlaDUB1 (Cdu1). Expression of Cdu1 is also connected to host cell Golgi apparatus fragmentation, a key process in CT infections. Cdu1 may this be an attractive drug target for the treatment of CT infections. However, a lead molecule for the development of novel potent inhibitors has been unknown so far. Sequence alignments and phylogenetic searches allocate Cdu1 in the CE clan of cysteine proteases. The adenovirus protease (adenain) also belongs to this clan and shares a high degree of structural similarity with Cdu1. Taking advantage of topological similarities between the active sites of Cdu1 and adenain, a target-hopping approach on a focused set of adenain inhibitors, developed at Novartis, has been pursued. The thereby identified cyano-pyrimidines represent the first active-site directed covalent reversible inhibitors for Cdu1. High-resolution crystal structures of Cdu1 in complex with the covalently bound cyano-pyrimidines as well as with its substrate ubiquitin have been elucidated. The structural data of this thesis, combined with enzymatic assays and covalent docking studies, provide valuable insights into Cdu1s activity, substrate recognition, active site pocket flexibility and potential hotspots for ligand interaction. Structure-informed drug design permitted the optimization of this cyano-pyrimidine based scaffold towards HJR108, the first molecule of its kind specifically designed to disrupt the function of Cdu1. The structures of potentially more potent and selective Cdu1 inhibitors are herein proposed. This thesis provides important insights towards our understanding of the structural basis of ubiquitin recognition by Cdu1, and the basis to design highly specific Cdu1 covalent inhibitors.}, subject = {Ubiquitin}, language = {en} } @phdthesis{Schulz2024, author = {Schulz, Daniel}, title = {Development of Inhibitory Control in Kindergarten Children}, doi = {10.25972/OPUS-35715}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357152}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {This dissertation explores the development and assessment of inhibitory control - a crucial component of executive functions - in young children. Inhibitory control, defined as the ability to suppress inappropriate responses (Verbruggen \& Logan, 2008), is essential for adaptable and goal-oriented behavior. The rapid and non-linear development of this cognitive function in early childhood presents unique challenges for accurate assessment. As children age, they often exhibit a ceiling effect in terms of response accuracy (Petersen et al., 2016), underscoring the need to consider response latency as well. Ideally, combining response latency with accuracy could yield a more precise measure of inhibitory control (e.g., Magnus et al., 2019), facilitating a detailed tracking of developmental changes in inhibitory control across a wider age spectrum. The three studies of this dissertation collectively aim to clarify the relationship between response accuracy, response latency, and inhibitory control across different stages of child development. Each study utilizes a computerized Pointing Stroop Task (Berger et al., 2000) to measure inhibitory control, examining the task's validity and the integration of dual metrics for a more comprehensive evaluation. The first study focuses on establishing the validity of using both response accuracy and latency as indicators of inhibitory control. Utilizing the framework of explanatory item-response modeling (De Boeck \& Wilson, 2004), the study revealed how the task characteristics congruency and item position influence both the difficulty level and timing aspects in young children's responses in the computerized Pointing Stroop task. Further, this study found that integrating response accuracy with latency, even in a basic manner, provides additional insights. Building upon these findings, the second study investigates the nuances of integrating response accuracy and latency, examining whether this approach can account for age-related differences in inhibitory control. It also explores whether response latencies may contain different information depending on the age and proficiency of the children. The study leverages novel and established methodological perspectives to integrate response accuracy and latency into a single metric, showing the potential applicability of different approaches for assessing inhibitory control development. The third study extends the investigation to a longitudinal perspective, exploring the dynamic relationship between response accuracy, latency, and inhibitory control over time. It assesses whether children who achieve high accuracy at an earlier age show faster improvement in response latency, suggesting a non-linear maturation pathway of inhibitory control. The study also examines if the predictive value of early response latency for later fluid intelligence is dependent on the response accuracy level. Together, these empirical studies contribute to a more robust understanding of the complex interaction between inhibitory control, response accuracy, and response latency, facilitating valid evaluations of cognitive capabilities in children. Moreover, the findings may have practical implications for designing educational strategies and clinical interventions that address the developmental trajectory of inhibitory control. The nuanced approach advocated in this dissertation suggests prioritizing accuracy in assessment and interventions during the early stages of children's cognitive development, gradually shifting the focus to response latency as children mature and secure their inhibitory control abilities.}, subject = {Kognitive Entwicklung}, language = {en} } @phdthesis{Bossert2024, author = {Bossert, Patrick}, title = {Statistical structure and inference methods for discrete high-frequency observations of SPDEs in one and multiple space dimensions}, doi = {10.25972/OPUS-36113}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-361130}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {The focus of this thesis is on analysing a linear stochastic partial differential equation (SPDE) with a bounded domain. The first part of the thesis commences with an examination of a one-dimensional SPDE. In this context, we construct estimators for the parameters of a parabolic SPDE based on discrete observations of a solution in time and space on a bounded domain. We establish central limit theorems for a high-frequency asymptotic regime, showing substantially smaller asymptotic variances compared to existing estimation methods. Moreover, asymptotic confidence intervals are directly feasible. Our approach builds upon realized volatilities and their asymptotic illustration as the response of a log-linear model with a spatial explanatory variable. This yields efficient estimators based on realized volatilities with optimal rates of convergence and minimal variances. We demonstrate our results by Monte Carlo simulations. Extending this framework, we analyse a second-order SPDE model in multiple space dimensions in the second part of this thesis and develop estimators for the parameters of this model based on discrete observations in time and space on a bounded domain. While parameter estimation for one and two spatial dimensions was established in recent literature, this is the first work that generalizes the theory to a general, multi-dimensional framework. Our methodology enables the construction of an oracle estimator for volatility within the underlying model. For proving central limit theorems, we use a high-frequency observation scheme. To showcase our results, we conduct a Monte Carlo simulation, highlighting the advantages of our novel approach in a multi-dimensional context.}, subject = {Stochastische partielle Differentialgleichung}, language = {en} } @phdthesis{Daum2024, author = {Daum, Stefanie}, title = {Nahrhafte Momente schaffen - Sinnbildgest{\"u}tzte Interviews (SigI) im Fallverstehen bei Lernbeeintr{\"a}chtigungen unter Ber{\"u}cksichtigung entwicklungsp{\"a}dagogischer Aspekte im K{\"o}nnen, Wissen und Wollen}, doi = {10.25972/OPUS-36035}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-360351}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {In den letzten Jahren stieg die Anzahl an f{\"o}rderbed{\"u}rftigen Sch{\"u}lern sowie an Sch{\"u}lern mit einer Migrations- bzw. Fluchtgeschichte an der Berufsschule. Damit entsteht eine neue Sch{\"u}lerklientel, die von einer hohen Sch{\"u}lerheterogenit{\"a}t und Lernstanddifferenz gepr{\"a}gt ist. Vermehrt sind auch eine sprachliche Armut sowie Lernbeeintr{\"a}chtigungen zu beobachten. Die Arbeit mit Sinnbildern im diagnostischen Prozess bei Lernbeeintr{\"a}chtigungen ist ein kleiner Baustein auf dem Weg dorthin, dass Lernen und damit auch ein Sich-Weiterentwickeln gelingen kann. Dabei pr{\"a}sentiert sich das l{\"o}sungs- sowie entwicklungsorientierte Verfahren als eine in Beziehung zueinander stehenden Einheit aus Lernbeeintr{\"a}chtigung, potenzielle L{\"o}sung und nahrhaften Boden. Lernbeeintr{\"a}chtigung: Der Trias liegt die Annahme zugrunde, dass der Lernprozess des Sch{\"u}lers gestoppt ist. Wenngleich der Sch{\"u}ler sp{\"u}rt, dass da etwas ist, das ihm beim Lernen im Weg steht, so ist er jedoch nicht in der Lage das Gesp{\"u}rte zu verbalisieren. Nahrhafter Boden: Mit Hilfe eines von Sinnbildern gest{\"u}tzten Interviews soll es gelingen, die vagen Vermutungen der Sch{\"u}ler hinsichtlich ihrer Lernbeeintr{\"a}chtigung zu versprachlichen. Dabei spielt die von den Bildern ausgehende Resonanz eine entscheidende Rolle. Durch sie k{\"o}nnen dem Sch{\"u}ler eigene implizite Denk- und Handlungsmuster gedanklich zug{\"a}nglich gemacht und versprachlicht werden. Potenzielle L{\"o}sung: Die im Rahmen des Sinnbildgest{\"u}tzten Interviews in Erfahrung gebrachten Informationen erm{\"o}glichen im besten Fall eine Sicht darauf, was dem Sch{\"u}ler in seinem gestoppten Lernprozess im Weg steht. Dabei geht es nicht darum eine kausale Ursache zu finden, sondern eine prozessorientierte sowie l{\"o}sungsorientierte Sichtweise einzunehmen. Die Versprachlichung der vagen Vermutungen erm{\"o}glicht ein Arbeiten mit dem Wissen in der realen Welt. Im Falle von Gelingen, kann der Interviewf{\"u}hrende die durch das Sinnbildgest{\"u}tzte Interview in Erfahrung gebrachten Lernbeeintr{\"a}chtigungen innerhalb der drei Lerndimensionen im K{\"o}nnen, Wissen und Wollen (Ellinger/Hechler 2021) verorten, um eine individuelle -auf die Lernbeeintr{\"a}chtigung zugeschnittene- Lernhilfe zu generieren.}, subject = {Symbol}, language = {de} } @phdthesis{Hegmann2024, author = {Hegmann, Reinhold}, title = {Pr{\"u}ferqualifikation und Pr{\"u}fungsqualit{\"a}t - Eine empirische Untersuchung privater pr{\"u}fungspflichtiger Unternehmen in Deutschland}, doi = {10.25972/OPUS-32254}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-322546}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Die Jahresabschlusspr{\"u}fung verfolgt das Ziel, die Verl{\"a}sslichkeit der Rechnungslegung zu best{\"a}tigen. Folglich kann sie einen wesentlichen Beitrag zu einem hohen Informationsniveau an den M{\"a}rkten leisten. Angesichts dieser großen {\"o}konomischen Bedeutung unternimmt der deutsche Gesetzgeber zahlreiche Anstrengungen, um eine hohe Pr{\"u}fungsqualit{\"a}t sicherzustellen. Die Sichtung der Wirtschaftspr{\"u}ferordnung zeigt hierbei, dass regulatorische Maßnahmen ergriffen werden, die am Kern der Jahresabschlusspr{\"u}fung ansetzen, n{\"a}mlich an den Berufsangeh{\"o}rigen selbst. So wurde der Zugang zum Berufsstand der vereidigten Buchpr{\"u}fer mehrmals geschlossen und wiederer{\"o}ffnet. Des Weiteren sind markante Anpassungen des Niveaus des Wirtschaftspr{\"u}fungsexamens im Zeitablauf zu erkennen. Bei der Jahresabschlusspr{\"u}fung der Unternehmen von {\"o}ffentlichem Interesse sind außerdem besondere Berufspflichten zu erf{\"u}llen. Zum einen ist diesen schweren Eingriffen in die Freiheit der Berufswahl und der Berufsaus{\"u}bung gemein, dass sie allesamt die Qualifikation des Abschlusspr{\"u}fers adressieren. Zum anderen werden die entsprechenden Gesetzes{\"a}nderungen mehrheitlich mit einer St{\"a}rkung der Pr{\"u}fungsqualit{\"a}t begr{\"u}ndet. Fraglich ist, inwiefern jene Facetten der Pr{\"u}ferqualifikation tats{\"a}chlich einen Einfluss auf die Pr{\"u}fungsqualit{\"a}t aus{\"u}ben. Aufgrund mangelnder Evidenz ergibt sich die Notwendigkeit, eine empirische Studie am deutschen Pr{\"u}fermarkt durchzuf{\"u}hren und somit den Beginn zur Schließung der identifizierten Forschungsl{\"u}cke zu setzen. Das Ziel der vorliegenden Dissertation besteht folglich darin, den Zusammenhang zwischen der Pr{\"u}ferqualifikation und der Pr{\"u}fungsqualit{\"a}t mittels Regressionsanalysen zu untersuchen. Dazu wurde ein einzigartiger Datensatz zu deutschen privaten pr{\"u}fungspflichtigen Kapitalgesellschaften mit unkonsolidierten Finanz- und Pr{\"u}ferinformationen im Zeitraum 2006-2018 mit insgesamt 217.585 grundlegenden Beobachtungen erhoben, bereinigt und aufbereitet. Da die Pr{\"u}fungsqualit{\"a}t nicht direkt beobachtbar ist, wird zwischen wahrgenommener Pr{\"u}fungsqualit{\"a}t und tats{\"a}chlicher Pr{\"u}fungsqualit{\"a}t unterschieden. Im Rahmen dieser Dissertation wird die wahrgenommene Pr{\"u}fungsqualit{\"a}t {\"u}ber Fremdkapitalkosten und die tats{\"a}chliche Pr{\"u}fungsqualit{\"a}t {\"u}ber absolute diskretion{\"a}re Periodenabgrenzungen approximiert. Die Ergebnisse der Hauptregressionen zeigen {\"u}berwiegend, dass kein Zusammenhang zwischen den Maßgr{\"o}ßen der Pr{\"u}ferqualifikation und der wahrgenommenen und tats{\"a}chlichen Pr{\"u}fungsqualit{\"a}t besteht. Die Zusatz- und Sensitivit{\"a}tsanalysen unterst{\"u}tzen diesen Befund. So k{\"o}nnen mit Blick auf die Berufszugangsregelungen keine Qualit{\"a}tsunterschiede zwischen den Berufsst{\"a}nden der Wirtschaftspr{\"u}fer und der vereidigten Buchpr{\"u}fer nachgewiesen werden. Auch innerhalb des Berufstandes der Wirtschaftspr{\"u}fer ergeben sich keine Hinweise auf ein Qualit{\"a}tsgef{\"a}lle zwischen den Pr{\"u}fergruppen, die unterschiedliche Examensanforderungen durchlebt haben. Hinsichtlich der Berufsaus{\"u}bungsregelungen ist zu beobachten, dass die zus{\"a}tzlichen Anforderungen an die Jahresabschlusspr{\"u}fung der Unternehmen von {\"o}ffentlichem Interesse nicht mit einer anderen Pr{\"u}fungsqualit{\"a}t bei privaten Unternehmen verbunden sind. Die beschriebenen regulatorischen Schritte des Gesetzgebers im Bereich der Pr{\"u}ferqualifikation erscheinen somit im Lichte einer verbesserten Pr{\"u}fungsqualit{\"a}t nicht zwingend gerechtfertigt.}, subject = {Pr{\"u}fungsqualit{\"a}t}, language = {de} } @phdthesis{Wagner2024, author = {Wagner, Tim Matthias}, title = {Characterization of 2D antimony lattices}, doi = {10.25972/OPUS-36329}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-363292}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Two-dimensional lattices are in the focus of research in modern solid state physics due to their novel and exotic electronic properties with tremendous potential for seminal future applications. Of particular interest within this research field are quantum spin Hall insulators which are characterized by an insulating bulk with symmetry-protected metallic edge states. For electrons within these one-dimensional conducting channels, spin-momentum locking enables dissipationless transport - a property which promises nothing short of a revolution for electronic devices. So far, however, quantum spin Hall materials require enormous efforts to be realized such as cryogenic temperatures or ultra-high vacuum. A potential candidate to overcome these shortcomings are two-dimensional lattices of the topological semi-metal antimony due to their potential to host the quantum spin Hall effect while offering improved resilience against oxidation. In this work, two-dimensional lattices of antimony on different substrates, namely Ag(111), InSb(111) and SiC(0001), are investigated regarding their atomic structure and electronic properties with complimentary surface sensitive techniques. In addition, a systematic oxidation study compares the stability of Sb-SiC(0001) with that of the two-dimensional topological insulators bismuthene-SiC(0001) and indenene-SiC(0001). A comprehensive experimental analysis of the \((\sqrt{3}\times\sqrt{3})R30^\circ\) Sb-Ag(111) surface, including X-ray standing wave measurements, disproves the proclaimed formation of a buckled antimonene lattice in literature. The surface lattice can instead be identified as a metallic Ag\(_2\)Sb surface alloy. Antimony on InSb(111) shows an unstrained Volmer-Weber island growth due to its large lattice mismatch to the substrate. The concomitant moir\'{e} situation at the interface imprints mainly in a periodic height corrugation of the antimony islands which as observed with scanning tunneling microscopy. On islands with various thicknesses, quasiparticle interference patterns allow to trace the topological surface state of antimony down to the few-layer limit. On SiC(0001), two different two-dimensional antimony surface reconstructions are identified. Firstly, a metallic triangular \$1\times1\$ lattice which constitutes the antimony analogue to the topological insulator indenene. Secondly, an insulating asymmetric kagome lattice which represents the very first realized atomic surface kagome lattice. A comparative, systematic oxidation study of elemental (sub-)monolayer materials on SiC(0001) reveals a high sensitivity of indenene and bismuthene to small dosages of oxygen. An improved resilience is found for Sb-SiC(0001) which, however, oxidizes nevertheless if exposed to oxygen. These surface lattices are therefore not suitable for future applications without additional protective measures.}, subject = {Antimon}, language = {en} } @phdthesis{Koerner2024, author = {K{\"o}rner, Jacob}, title = {Theoretical and numerical analysis of Fokker-Planck optimal control problems by first- and second-order optimality conditions}, doi = {10.25972/OPUS-36299}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-362997}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {In this thesis, a variety of Fokker--Planck (FP) optimal control problems are investigated. Main emphasis is put on a first-- and second--order analysis of different optimal control problems, characterizing optimal controls, establishing regularity results for optimal controls, and providing a numerical analysis for a Galerkin--based numerical scheme. The Fokker--Planck equation is a partial differential equation (PDE) of linear parabolic type deeply connected to the theory of stochastic processes and stochastic differential equations. In essence, it describes the evolution over time of the probability distribution of the state of an object or system of objects under the influence of both deterministic and stochastic forces. The FP equation is a cornerstone in understanding and modeling phenomena ranging from the diffusion and motion of molecules in a fluid to the fluctuations in financial markets. Two different types of optimal control problems are analyzed in this thesis. On the one hand, Fokker--Planck ensemble optimal control problems are considered that have a wide range of applications in controlling a system of multiple non--interacting objects. In this framework, the goal is to collectively drive each object into a desired state. On the other hand, tracking--type control problems are investigated, commonly used in parameter identification problems or stemming from the field of inverse problems. In this framework, the aim is to determine certain parameters or functions of the FP equation, such that the resulting probability distribution function takes a desired form, possibly observed by measurements. In both cases, we consider FP models where the control functions are part of the drift, arising only from the deterministic forces of the system. Therefore, the FP optimal control problem has a bilinear control structure. Box constraints on the controls may be present, and the focus is on time--space dependent controls for ensemble--type problems and on only time--dependent controls for tracking--type optimal control problems. In the first chapter of the thesis, a proof of the connection between the FP equation and stochastic differential equations is provided. Additionally, stochastic optimal control problems, aiming to minimize an expected cost value, are introduced, and the corresponding formulation within a deterministic FP control framework is established. For the analysis of this PDE--constrained optimal control problem, the existence, and regularity of solutions to the FP problem are investigated. New \$L^\infty\$--estimates for solutions are established for low space dimensions under mild assumptions on the drift. Furthermore, based on the theory of Bessel potential spaces, new smoothness properties are derived for solutions to the FP problem in the case of only time--dependent controls. Due to these properties, the control--to--state map, which associates the control functions with the corresponding solution of the FP problem, is well--defined, Fr{\´e}chet differentiable and compact for suitable Lebesgue spaces or Sobolev spaces. The existence of optimal controls is proven under various assumptions on the space of admissible controls and objective functionals. First--order optimality conditions are derived using the adjoint system. The resulting characterization of optimal controls is exploited to achieve higher regularity of optimal controls, as well as their state and co--state functions. Since the FP optimal control problem is non--convex due to its bilinear structure, a first--order analysis should be complemented by a second--order analysis. Therefore, a second--order analysis for the ensemble--type control problem in the case of \$H^1\$--controls in time and space is performed, and sufficient second--order conditions are provided. Analogous results are obtained for the tracking--type problem for only time--dependent controls. The developed theory on the control problem and the first-- and second--order optimality conditions is applied to perform a numerical analysis for a Galerkin discretization of the FP optimal control problem. The main focus is on tracking-type problems with only time--dependent controls. The idea of the presented Galerkin scheme is to first approximate the PDE--constrained optimization problem by a system of ODE--constrained optimization problems. Then, conditions on the problem are presented such that the convergence of optimal controls from one problem to the other can be guaranteed. For this purpose, a class of bilinear ODE--constrained optimal control problems arising from the Galerkin discretization of the FP problem is analyzed. First-- and second--order optimality conditions are established, and a numerical analysis is performed. A discretization with linear finite elements for the state and co--state problem is investigated, while the control functions are approximated by piecewise constant or piecewise quadratic continuous polynomials. The latter choice is motivated by the bilinear structure of the optimal control problem, allowing to overcome the discrepancies between a discretize--then--optimize and optimize--then--discretize approach. Moreover, second--order accuracy results are shown using the space of continuous, piecewise quadratic polynomials as the discrete space of controls. Lastly, the theoretical results and the second--order convergence rates are numerically verified.}, subject = {Parabolische Differentialgleichung}, language = {en} } @phdthesis{Kappes2024, author = {Kappes, Alexander}, title = {High-Redshift Blazars Observed by the International LOFAR Telescope}, doi = {10.25972/OPUS-36144}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-361444}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {This work presents the first ILT observations of high redshift blazars and their study in terms of jet evolution, morphology, and interaction with the surrounding medium. Each of these represents a highly topical area of astronomywith a large number of open questions. To better understand Active Galactic Nuclei (AGN) and their fundamental inner workings, new techniques are needed to exploit the full potential of the next generation of radio interferometers. Some of these tools are presented here and applied to one of the latest generation of software radio telescopes. A major focus of the studies presented is on the unification model, where the observed blazars are discussed for their properties to be rotated counterparts of Fanaroff-Riley Class II (FR-II) radio galaxies, when classified as Flat Spectrum Radio Quasars (FSRQs). In addition, multiwavelength information has been included in the analysis. Both studies are feasibility studies that will serve as a basis for future similar studies. The characteristics discussed and their interpretation do not allow conclusions to be drawn for their respective populations. However, by applying them to a larger number of targets, population studies will be possible. The first chapters introduce the necessary topics, AGN, principles of radio observations and ILT, in the necessary depth to provide the reader with a solid knowledge base. They are particularly important for understanding the current limits and influences of uncertainties in the observation, calibration and imaging process. But they also shed light on realistic future improvements. A particular focus is on the development and evolution of the LOw-Frequency ARray (LOFAR)-Very Long Baseline Interferometry (VLBI) pipeline. With the tools at hand, the first study addresses the high redshift blazar S5 0836+710 \$(z=2.218)\$, which has been observed at various wavelengths and resolutions. It has a disrupted one-sided jet with an associated extended region further out. Despite the excellent wavelength coverage, only the additional ILT observations provided a complete picture of the source. With the data, the extended region could be classified as a hotspot moving at slightly relativistic speeds.. With the ILT data it was also possible to extract the flux of the core region of the AGN, and in projection to reveal the mixed counter-hotspot behind it. This also allowed constraints on jet parameters and environmental properties to be modelled, which were previously inconclusive. Technically, this study shows that the ILT can be used as an effective VLBI array for compact sources with small angular scales. However, the detection of faint components beyond redshifts of \$z=2\$ may require the capabilities of the Square Kilometre Array (SKA) to provide a significant number of detections to enable statistical conclusions. The second study uses a much improved calibration pipeline to analyse the high redshift blazar GB1508+5714 \$(z=4.30)\$. The ILT data revealed a previously unseen component in the eastern direction. A spectral index map was generated from the Karl G. Jansky Very Large Array (VLA) data, showing spectral index values of \$-1.2_{-0.2}^{+0.4}\$ for the western component, steeper than \$-1.1\$ for the eastern region, and \$0.023 \pm 0.007\$ for the core. Using the information provided by the ILT observation, as well as multi-wavelength information from other observations ranging from the long radio wavelengths to the \$\gamma\$ regime, four models were developed to interpret the observed flux with different emission origins. This also allowed to test a proposed interaction channel of the electrons provided by the jet, to cool off via inverse compton scattering with the Cosmic Microwave Background (CMB) photons, rather than by the usual synchrotron emission. This is referred to as cmb quenching in the literature, which could be shown in the study, to be necessary in any case. Finally, one of the four models was considered in which the hotspots in the detected components are unresolved and mixed by the lobe emission, with the X-ray emission coming from the lobes and partially mixed by the bright core region. The results of this preferred model are consistent with hotspots in a state of equipartition and lobes almost so. The study shows that high redshift blazars can be studied with the ILT, and expanding the sample of high redshift blazars resolved at multiple frequencies will allow a statistical study of the population. Finally, this work successfully demonstrates the powerful capabilities of the ILT to address questions that were previously inaccessible. The current state of the LOFAR-VLBI pipeline, when properly executed, allows work on the most challenging objects and will only improve in the future. In particular, this gives a glimpse of the possibilities that SKA will bring to astronomy.}, subject = {Blazar}, language = {en} } @phdthesis{Zuber2024, author = {Zuber, Jonas Maximilian}, title = {Evaluation von Sedierungen und Allgemeinan{\"a}sthesien zur Durchf{\"u}hrung bildgebender Verfahren bei S{\"a}uglingen bis zum 6. Lebensmonat}, doi = {10.25972/OPUS-36111}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-361111}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Vorliegende Untersuchung am Universit{\"a}tsklinikum W{\"u}rzburg sowie die Befragung von An{\"a}sthesisten/An{\"a}sthesistinnen im Raum der 3 DACH-L{\"a}nder zeigen, dass bildgebende Verfahren bei S{\"a}uglingen mit einer niedrigen Rate an Komplikationen, zumeist in medikament{\"o}ser Sedierung mit Propofol, durchgef{\"u}hrt werden. Wie international {\"u}blich ist im S{\"a}uglingsalter die Magnetresonanztomographie das bildgebende Verfahren der Wahl und wird, mit {\"u}berzeugender H{\"a}ufigkeit, erfolgreich durchgef{\"u}hrt. Die Untersuchung am Universit{\"a}tsklinikum W{\"u}rzburg legt nahe, dass m{\"a}nnliche S{\"a}uglinge h{\"a}ufiger eine Bildgebung ben{\"o}tigen und h{\"a}ufiger h{\"o}heren ASA-Kategorie zugeschrieben werden. Dabei scheinen sie auch h{\"a}ufiger Komplikationen zu erleben und bed{\"u}rfen daher besonderer Aufmerksamkeit. Eine eventuelle Alternative zur Sedierung kann dabei die „feed-and-sleep" Methode darstellen. In unserer Umfrage konnten wir erheben, dass diese Methode bisher wenig verbreitet ist, obwohl in diesem Zusammenhang eventuell Abl{\"a}ufe und Prozesszeiten strukturiert und optimiert werden k{\"o}nnen, da beispielsweise die Nach{\"u}berwachung entf{\"a}llt. Vorstellbar w{\"a}re beispielsweise, mehrere S{\"a}uglinge zum gleichen Zeitpunkt ins MRT zu bestellen, um gegebenenfalls den am fr{\"u}hesten eingeschlafenen S{\"a}ugling vorzuziehen. Diese Methode sollte zuk{\"u}nftig Einzug in die wissenschaftliche Untersuchung von bildgebenden Verfahren bei S{\"a}uglingen finden. Die Umfrage im deutschsprachigen Raum zeigt eine Leitlinien-gerechte Betreuung von S{\"a}uglingen f{\"u}r bildgebende Verfahren, die mit einer hohen Qualit{\"a}t, und zumeist erfolgreich von erfahrenen An{\"a}sthesisten/An{\"a}sthesistinnen durchgef{\"u}hrt wird. Eventuelle Verbesserungen k{\"o}nnen im Bereich der Ausbildung nachfolgender {\"A}rztinnen/{\"A}rzte und in der h{\"a}ufigeren Verwendung der „feed-and-sleep" Methode liegen, die vielen Kollegen/Kolleginnen bekannt ist, aber nur selten durchgef{\"u}hrt wird. Ziel ist eine qualitativ hochwertige, schnellstm{\"o}glich durchgef{\"u}hrte Bildgebung, die ohne oder mit der niedrigst m{\"o}glichen Dosierung eines sedierenden Medikamentes zu erreichen ist.}, subject = {Sedierung}, language = {de} } @phdthesis{Fischer2024, author = {Fischer, Jonas Maria}, title = {Ph{\"a}notyp und Funktion von Follikul{\"a}ren Helfer Zell-{\"a}hnlichen T-Zellen im entz{\"u}ndeten Gelenk von Patientinnen und Patienten mit Juveniler Idiopathischer Arthritis}, doi = {10.25972/OPUS-36302}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-363022}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Innerhalb der Juvenilen Idiopathischen Arthritis (JIA) bilden Patienten mit Antinukle{\"a}ren Antik{\"o}rpern (ANA) Subgruppen-{\"u}bergreifend eine klinisch homogene Erkrankungsgruppe. Ob diesen klinischen Gemeinsamkeiten jedoch auch eine einheitliche Pathogenese zugrunde liegt, ist bisher unbekannt. Sogenannte periphere T-Helferzellen (TPH) spielen im Kontext zahlreicher Autoimmunerkrankungen eine entscheidende Rolle bei der Aktivierung autoreaktiver B-Zellen. Ziel dieser Arbeit war daher die ph{\"a}notypische und funktionelle Analyse von PD-1hiCXCR5-CD4+ TPH-Zellen, sowie deren Verteilung in der Synovialfl{\"u}ssigkeit von Patienten unterschiedlicher Subgruppen der JIA. Hierzu wurden Ph{\"a}notyp und Zytokinprofil von PD-1hiCD4+ T-Zellen durchflusszytometrisch analysiert. Der funktionelle Einfluss von PD-1hiCD4+ T-Zellen auf die B-Zell-Differenzierung wurde mittels in vitro Kokulturen FACS-sortierter TPH-Zellen der Synovialfl{\"u}ssigkeit untersucht. IL-21- und IL-17-produzierende T-Ged{\"a}chtniszellen der Synovialfl{\"u}ssigkeit zeigten eine negative Korrelation zueinander. Die IL-21-Produktion ging besonders von PD-1hiCXCR5-HLA-DR+CD4+ T-Zellen aus, welche besonders in den Gelenken ANA-positiver JIA-Patienten akkumulierten. Diese Population zeigte ph{\"a}notypische {\"A}hnlichkeit mit TPH-Zellen und leistete in vitro effiziente B-Zell-Hilfe zu Plasmazelldifferenzierung und Immunglobulinsekretion, induzierte jedoch zudem einen CD21lo/-CD11c+T-bet+ Ph{\"a}notyp in B-Zellen. Passend hierzu bestand auch ex vivo eine signifikante Korrelation zwischen TPH und CD21lo/-CD11c+T-bet+ doppelt-negativen B-Zellen (BDN). Es konnte also die Expansion einer spezifischen T-Zellpopulation mit ph{\"a}notypischen und funktionellen Charakteristika von TPH-Zellen beobachtet und deren funktioneller Zusammenhang mit CD21lo/-CD11c+T-bet+ BDN in der Synovialfl{\"u}ssigkeit von JIA-Patienten aufgezeigt werden. Dies k{\"o}nnte die Autoimmunantwort auf ubiquit{\"a}re Autoantigene innerhalb betroffener Gelenke ANA-positiver JIA-Patienten widerspiegeln.}, subject = {Rheumatologie}, language = {de} } @phdthesis{Swain2024, author = {Swain, Asim}, title = {Helically Twisted Graphene Nanoribbons: Bottom-up Stereospecific Synthesis and Characterization}, doi = {10.25972/OPUS-36016}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-360164}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Over the past decade, substantial progress has been made in synthesizing atomically precise carbon nanostructures, with a focus on graphene nanoribbons (NRs) through advanced synthetic techniques. Despite these advancements, precise control over the stereochemistry of twisted NRs remains challenging. This thesis introduces a strategic approach to achieve absolute control over the single-handed helical conformation in a cove-edged NR, utilizing enantiopure [n]helicenes as a molecular wrench to intricately dictate the overall conformation of the NR. Enantiopure [7]helicenes were stitched to the terminal K-regions of a conjugated pyrene NR using a stereospecific and site-selective palladium(II)-catalyzed annulative π-extension (APEX) reaction, resulting in a helically twisted NR with an end-to-end twist of 171°, the second-largest twist reported so far in the literature for twistacenes. The helical end-to-end twist increases with each addition of benzene ring to the central acene core, suggesting that the extra strain induced by the terminal [7]helicenes maintains such a high level of twist. The quantum chemical calculations were conducted to investigate the impact of twisting on the conformational population. At room temperature, the central backbone of the nanoribbon adopts the twisted helicity opposite to that of the attached [7]helicene, constituting around 99\% of the molecular population. For instance, (P)-[7]helicenes produce a left-handed helical nanoribbon, while (M)-[7]helicenes produce a right-handed helical nanoribbon. In the presence of helicenes of opposite chirality, the nanoribbon adopts a waggling conformation. The helically twisted nanoribbons are conformationally robust, as variable temperature chiroptical measurements showed no change in CD and CPL spectra. The proposed strategy, involving the late-stage addition of [n]helicene units through the APEX reaction, appears promising for streamlining the synthesis of diverse cove edge NR variants with desired conformations. In addition to single-handed helically twisted nanoribbons, the symmetry-based functional properties of C2 and C1 symmetric pyrene-fused single and double [n]helicene compounds were studied. Owing to its higher structural rigidity, the C1 symmetric heptagonal ring-containing molecules exhibited exceptional configurational stability along with remarkable chiroptical properties compared to their C2 symmetric as well as pristine helicene congeners.}, subject = {Helicene}, language = {en} } @phdthesis{deSunda2024, author = {de Sunda, Angela}, title = {Effekte der Tiefenhirnstimulation bei Patienten mit idiopathischem Parkinson-Syndrom auf Symptome der Stimme und des Sprechens}, doi = {10.25972/OPUS-36301}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-363014}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Sprech- und Stimmst{\"o}rungen sind h{\"a}ufige Symptome der Idiopathischen Parkinson Erkrankung (IPS), wobei bis zu 89\% der Patienten im Verlauf der Krankheit unter einer Dysarthrie leiden. Die Tiefenhirnstimulation des Nucleus subthalamicus (STN-DBS) ist eine etablierte Behandlung f{\"u}r die motorischen Symptome des IPS (Allert et al., 2004). W{\"a}hrend STN-DBS positive Effekte auf einige Teilfunktionsbereiche der Dysarthrie zu haben scheint, berichten die meisten Studien entweder {\"u}ber keine Verbesserung oder eine Verschlechterung der Sprech- und Stimmfunktionen nach Implantation der STN-DBS (Tsuboi et al., 2015; Wang et al., 2003; Wertheimer et al., 2014). Klinische Erfahrungswerte sowie Fallberichte und Studien lassen vermuten, dass diese sprachtherapeutisch relevanten Nebenwirkungen unabh{\"a}ngig von der therapeutischen Wirksamkeit der STN-DBS sind und daher als unerw{\"u}nschte, aber nicht therapieimmanente Interferenzfaktoren anzusehen sind (Bouthour et al., 2018), die es genauer zu untersuchen gilt, da die Lebensqualit{\"a}t von IPS-Erkrankten als stark einschr{\"a}nkend wahrgenommen wird (Hariz et al., 2010). Eine aufwendige und methodisch fundierte Klassifizierung wurde von Tsuboi und Kollegen vorgenommen, die im Zusammenhang mit STN-DBS f{\"u}nf Cluster von Sprech- und Stimmst{\"o}rungen identifizierten (Tanaka et al., 2020; Tsuboi et al., 2015, 2017). Dazu z{\"a}hlten die Ph{\"a}notypen „spastische Dysarthrie", „Stottern", „rigid-hypokinetischer Typ", „behauchte Stimme" und „gepresste Stimme". Erste Hinweise lassen darauf schließen, dass die Nebenwirkungen von STN-DBS auf die Stimulation spezifischer Gehirnkreise zur{\"u}ckzuf{\"u}hren sein k{\"o}nnte (Fox et al., 2014). In dieser Arbeit wird eine retrospektive Studie mit STN-DBS stimulierten IPS Erkrankten vorgestellt, die sprachtherapeutisch relevante Sprech- und Stimmst{\"o}rungen unter zwei Bedingungen bewertet (ein- und ausgeschaltete Stimulation) sowie eine prospektive Studie mit den beiden gleichen Bedingungen. Beide Studien haben das Ziel einer Replizierbarkeit der Ergebnisse von Tsuboi et al. (2015, 2017). Die zweite prospektive Studie bezieht außerdem konnektombasierte Daten ein. Die Ergebnisse beider Studien lassen quantitativ keine Signifikanzen hinsichtlich der o.g. dysarthrischen Ph{\"a}notypen zu, quantitativ lassen sich jedoch deutliche Tendenzen {\"a}hnlich der Ausgangsstudie erkennen. Zudem wurden das Cluster „Stottern" in der retrospektiven Studie als weiteres m{\"o}glicherweise STN-DBS immantentes Cluster identifiziert. In der prospektiven Studie wurde ein Cluster hinzugef{\"u}gt, da in den Beurteilungen zus{\"a}tzlich die Symptomatik „hasty speech" oder auch „hastiges Sprechen" beobachtet wurde.}, subject = {Dysarthrie}, language = {de} } @phdthesis{Roger2024, author = {Roger, Chantal}, title = {Photophysics and Spin Chemistry of Triptycene Bridge Donor-Acceptor-Triads}, doi = {10.25972/OPUS-36303}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-363031}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {The goal of this thesis was to investigate the influence of rotational restriction between individual parts and of the varying electron density in the bridging unit of D B A systems on the exchange interaction 2J, and thus the electronic coupling between a donor state and an acceptor state. A better understanding of how to influence the underlaying spin dynamics in such donor acceptor systems can open up the door to new technologies, such as modern molecular electronics or optoelectronic devices. Therefore, three series of molecules consisting of a TAA electron donor, a TTC or ATC bridging unit and a PDI electron acceptor were studied. To investigate the influence of rotational restriction on 2J and the electronic coupling, a series of four rotationally hindered triads (chapter 6) was synthesised. The dihedral angle between the TAA and the TTC as well as between the TTC and the PDI was restricted by ortho methyl groups at the phenylene linkers of the connecting ends to the TTC bridge, producing a twist around the linking single bond which minimises the π overlap. The triads exhibit varying numbers of ortho methyl groups and therefore different degrees of rotational restriction. In order to shine light on the influence of varying electron density on 2J and the electronic coupling, a series of four substituted triptycene triads (chapter 7) was synthesised. The electron density in the TTC bridging unit was varied by electron donating and electron withdrawing groups in 12,13 position of the TTC bridging unit and thus varying its HOMO/LUMO energy. The last series of two anthracene bridge triads (chapter 8) connected both approaches by restricting the rotation with ortho methyl groups and simultaneously by varying the bridge energies. In order to obtain the electronic properties, steady state absorption and emission spectra of all triads were investigated (chapter 4). Here, all triads show spectral features associated with the separate absorption bands of TAA and the PDI moiety. The reduced QYs, compared to the unsubstituted PDI acceptor, indicate a non radiative quenching mechanism in all triads. The CV data (chapter 5) were used to calculate the energies of possible CSSs and those results were used to assign the CR dynamics into the different Marcus regions. fs TA measurements reveal that all triads form a CSS upon excitation of the PDI moiety. The lifetimes of the involved states and the rate constants were determined by global exponential fits and global target analysis. The CR dynamics upon depopulation of the CSSs were investigated using external magnetic field dependent ns TA spectroscopy. The ns TA maps show that all triads recombine via CRT pathway populating the local 3PDI state in toluene and provided the respective lifetimes. The approximate QYs of triplet formation were determined using actinometry. The magnetic field dependent ns TA data reveal the exchange interaction 2J between singlet and triplet CSS for each triad. Those magnetic field dependent ns TA data in toluene were furthermore treated using a quantum mechanical simulation (done by U.E. Steiner) to extract the rate constants kT and kS for CRT and CRS, respectively. However, the error margins of kS were rather wide. Finally, the electronic couplings between the donor and the acceptor states were obtained by combining the aforementioned experimental results of the rate constants and applying the Bixon Jortner theoretical description of diabatic ET and Andersons perturbative theory of the exchange coupling. Therefore, the experimentally determined values of 2J and the calculated values of kCS and kT were used. The rate constant kS was calculated based on the electronic coupling V1CSS 1S0. The rotationally hindered triads (chapter 6) show a strong influence of the degree of rotational restriction on the lifetimes and rate constants of the CS processes. The rate constants of CS are increasing with increasing rotational freedom. The magnetic field dependent decay data show that the exchange interactions increase with increasing rotational freedom. Based on the CR dynamics, the calculated electronic couplings of the ET processes reflect the same trend along the series. Here, only singlet couplings turned out to be strongly influenced while the triplet couplings are not. Therefore, this series shows that the ET dynamics of donor acceptor systems can strongly be influenced by restricting the rotational freedom. In the substituted triptycene triads (chapter 7), decreasing electron density in the bridging unit causes a decrease of the CS rate constants. The magnetic field dependent decay data show that with decreasing electron density in the bridge the exchange interaction decreases. The CR dynamics-based rate constants and the electronic couplings follow the same trend as the exchange interaction. This series shows that varying the HOMO/LUMO levels of the connecting bridge between donor and acceptor strongly influences the ET processes. In the anthracene bridge triads (chapter 8), the CS process is slow in both triads. The CR was fast in the anthracene triad and is slowed down in the methoxy substituted anthracene bridge triad. The increase of the exchange interaction with increasing electron density in the bridge was more pronounced than in the substituted triptycene triads. Thus, the variation of electron density in the bridge strongly influences the ET processes even though the rotation is restricted. In this thesis, it was shown that the influence of the rotational hindrance as well as the electron density in a connecting bridge have strong influence on all ET processes and the electronic coupling in donor acceptor systems. These approaches can therefore be used to modify magnetic properties of new materials.}, subject = {Rotation}, language = {en} } @phdthesis{deGraafgebButtler2024, author = {de Graaf [geb. Buttler], Simone Linda}, title = {From Small to Large Data: Leveraging Synthetic Data for Inventory Management}, doi = {10.25972/OPUS-36136}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-361364}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {In a world of constant change, uncertainty has become a daily challenge for businesses. Rapidly shifting market conditions highlight the need for flexible responses to unforeseen events. Operations Management (OM) is crucial for optimizing business processes, including site planning, production control, and inventory management. Traditionally, companies have relied on theoretical models from microeconomics, game theory, optimization, and simulation. However, advancements in machine learning and mathematical optimization have led to a new research field: data-driven OM. Data-driven OM uses real data, especially time series data, to create more realistic models that better capture decision-making complexities. Despite the promise of this new research area, a significant challenge remains: the availability of extensive historical training data. Synthetic data, which mimics real data, has been used to address this issue in other machine learning applications. Therefore, this dissertation explores how synthetic data can be leveraged to improve decisions for data-driven inventory management, focusing on the single-period newsvendor problem, a classic stochastic optimization problem in inventory management. The first article, "A Meta Analysis of Data-Driven Newsvendor Approaches", presents a standardized evaluation framework for data-driven prescriptive approaches, tested through a numerical study. Findings suggest model performance is not robust, emphasizing the need for a standardized evaluation process. The second article, "Application of Generative Adversarial Networks in Inventory Management", examines using synthetic data generated by Generative Adversarial Networks (GANs) for the newsvendor problem. This study shows GANs can model complex demand relationships, offering a promising alternative to traditional methods. The third article, "Combining Synthetic Data and Transfer Learning for Deep Reinforcement Learning in Inventory Management", proposes a method using Deep Reinforcement Learning (DRL) with synthetic and real data through transfer learning. This approach trains a generative model to learn demand distributions, generates synthetic data, and fine-tunes a DRL agent on a smaller real dataset. This method outperforms traditional approaches in controlled and practical settings, though further research is needed to generalize these findings.}, subject = {Bestandsmanagement}, language = {en} } @phdthesis{Iosip2024, author = {Iosip, Anda-Larisa}, title = {Molecular Mechanosensing Mechanisms of the Carnivorous Plant \(Dionaea\) \(muscipula\)}, doi = {10.25972/OPUS-28764}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-287649}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Plants are able to sense mechanical forces in order to defend themselves against predators, for instance by synthesizing repellent compounds. Very few plants evolved extremely sensitive tactile abilities that allow them to perceive, interpret and respond by rapid movement in the milliseconds range. One such rarity is the charismatic Venus flytrap (Dionaea muscipula) - a carnivorous plant which relies on its spectacular active trapping strategy to catch its prey. The snapping traps are equipped with touch-specialised trigger hairs, that upon bending elicit an action potential (AP). This electrical signal originates within the trigger hairs' mechanosensory cells and further propagates throughout the whole trap, alerting the plant of potential prey. Two APs triggered within thirty seconds will set off the trap and more than five APs will initiate the green stomach formation for prey decomposition and nutrient uptake. Neither the molecular components of the plant's AP nor the Venus flytrap's fast closure mechanism have been fully elucidated yet. Therefore, the general objective of this study is to expound on the molecular basis of touch perception: from AP initiation to trap closure and finally to stomach formation. The typical electrical signal in plants lasts for minutes and its shape is determined by the intensity of the mechanical force applied. In contrast, the Venus flytrap's one-second AP is of all-or-nothing type, similar in shape to the animal AP. In order to gain more insight into the molecular components that give rise to the Venus flytrap's emblematic AP, the transcriptomic landscape of its unique mechanotransducer - the trigger hair - was compared to the rest of the non-specialised tissues and organs. Additionally, the transcriptome of the electrically excitable fully-developed adult trap was compared to non-excitable juvenile traps that are unable to produce sharp APs. Together, the two strategies helped with the identification of electrogenic channels and pumps for each step of the AP as follows: (1) the most specific to the trigger hair was the mechanosensitive channel DmMSL10, making up the best candidate for the initial AP depolarization phase, (2) the K+ outward rectifier DmSKOR could be responsible for repolarisation, (3) further, the proton pump DmAHA4, might kick in during repolarisation and go on with hyperpolarisation and (4) the hyperpolarization- and acid-activated K+ inward rectifier KDM1 might contribute to the re-establishment of electrochemical gradient and the resting potential. Responsible for the AP-associated Ca2+ wave and electrical signal propagation, the glutamate-like receptor DmGLR3.6 was also enriched in the trigger hairs. Together, these findings suggest that the reuse of genes involved in electrical signalling in ordinary plants can give rise to the Venus flytrap's trademark AP. The Venus flytrap has been cultivated ever since its discovery, generating more than one hundred cultivars over the years. Among them, indistinguishable from a normal Venus flytrap at first sight, the 'ERROR' cultivar exhibits a peculiar behaviour: it is unable to snap its traps upon two APs. Nevertheless, it is still able to elicit normal APs. To get a better understanding of the key molecular mechanisms and pathways that are essential for a successful trap closure, the 'ERROR' mutant was compared to the functional wild type. Timelapse photography led to the observation that the 'ERROR' mutants were able to leisurely half close their traps when repeated mechanostimulation was applied (10 minutes after 20 APs, 0.03 Hz). As a result of touch or wounding in non-carnivorous plants, jasmonic acid (JA) is synthesized, alerting the plants of potential predators. Curiously, the JA levels were reduced upon mechanostimulation and completely impaired upon wounding in the 'ERROR' mutant. In search of genes accountable for the 'ERROR' mutant's defects, the transcriptomes of the two phenotypes were compared before and after mechanostimulation (1h after 10 APs, 0.01 Hz). The overall dampened response of the mutant compared to the wild type, was reflected at transcriptomic level as well. Only about 50\% of wild type's upregulated genes after touch stimulation were differentially expressed in 'ERROR' and they manifested only half of the wild type's expression amplitude. Among unresponsive functional categories of genes in 'ERROR' phenotype, there were: cell wall integrity surveilling system, auxin biosynthesis and stress-related transcription factors from the ethylene-responsive AP2/ERF and C2H2-ZF families. Deregulated Ca2+-decoding as well as redox-related elements together with JA-pathway components might also contribute to the malfunctioning of the 'ERROR' mutant. As the mutant does not undergo full stomach formation after mechanical treatment, these missing processes represent key milestones that might mediate growth-defence trade-offs under JA signalling. This confirms the idea that carnivory has evolved by recycling the already available molecular machineries of the ubiquitous plant immune system. To better understand the mutant's defect in the trap snapping mechanism, the ground states (unstimulated traps) of the two phenotypes were compared. In this case, many cell wall-related genes (e.g. expansins) were downregulated in the 'ERROR' mutant. For the first time, these data point to the importance of a special cell wall architecture of the trap, that might confer the mechanical properties needed for a functional buckling system - which amplifies the speed of the trap closure. This study provides candidate channels for each of the AP phases that give rise to and shape the sharp Venus flytrap-specific AP. It further underlines the possible contribution of the cell wall architecture to the metastable ready-to-snap configuration of the trap before stimulation - which might be crucial for the buckling-dependent snapping. And finally, it highlights molecular milestones linked to defence responses that ensure trap morphing into a green stomach after mechanostimulation. Altogether, these processes prove to be interdependent and essential for a successful carnivorous lifestyle.}, subject = {Venusfliegenfalle}, language = {en} }