Die Ausstellung „Fakt – Fake“ der Universitätsbibliothek Würzburg im Herbst 2024 war Anlass, sich mit der wohl bekanntesten Fossilienfälschung des 18. Jahrhunderts, den sogenannten Würzburger Lügensteinen, erneut zu beschäftigen. Durch die Untersuchung bislang unberücksichtigter zeitgenössischer Quellen – zu den beteiligten Personen und zu den Lebensbedingungen in Eibelstadt, dem „Fundort“ der Steine – gelingt ein differenzierterer Blick auf die Hintergründe der Affäre. Ein eigenes Kapitel befasst sich mit der Rezeptionsgeschichte. Deren Analyse zeigt, dass zahlreiche Behauptungen, die scheinbar gesichert sind, sich als spätere Zutaten erweisen, die mehr über ihre eigene Entstehungszeit aussagen als über die Vorgänge selbst. Im Anhang sind die Verhörprotokolle der amtlichen Untersuchung aus dem Jahr 1726, die sich heute im Staatsarchiv Würzburg befinden, abgebildet und transkribiert, womit weitere Forschungen zu diesem Thema erleichtert werden.

Trypanosoma, a genus of parasitic protists, is responsible for trypanosomiasis, a disease that affects both humans and animals, with a wide impact across 36 countries in sub-Saharan Africa. The transmission of these parasites is intimately linked to their blood-sucking vector, the tsetse fly. Once the tsetse fly takes up trypanosomes during a bloodmeal, the parasites undergo a complex developmental process within the fly's alimentary tract before reaching the fly's salivary glands or mouthparts and differentiating back into a mammalian infective stage. This intricate relationship underscores the importance of understanding the interaction between trypanosomes and tsetse flies in combating the spread of this neglected tropical disease. Subspecies of Trypanosoma brucei are the main cause of human African trypanosomiasis (HAT) while also playing a large role in animal African trypanosomiasis (AAT). In the mammalian host, T. brucei has two bloodstream forms, the long, proliferative slender form and the short-lived, cell cycle-arrested stumpy form. Slender forms dominate early on in infections and differentiate into stumpy forms in a density-dependent manner. The dogma of the past two decades suggested that the transition from slender to stumpy forms was thought to accomplish two functions. The first was to regulate the parasite load in the host, thereby reducing virulence, prolonging infections, and consequently increasing the chances of transmission. The second was that the stumpy form was thought to be the only developmental form able to infect the tsetse fly and spread the disease. This was called into question in 2021 however, when it was shown that slender forms could also infect tsetse flies (Schuster et al., 2021). This finding caused a debate as to whether slender forms can truly infect tsetse flies without using the infection-enhancing methods for fly infections commonly applied in a laboratory setting. The differentiation from stumpy cells to the first fly-resident form, the procyclic form has been studied in depth. While it has been known that slender cells can be differentiated to procyclic forms in vitro, the relevance of this to in vivo fly infections has not been extensively considered. The possibility that both bloodstream form trypanosomes might be able to infect the tsetse fly would have major implications in disease epidemiology. The main focus of this thesis was to confirm that slender bloodstream forms can infect tsetse flies in a natural infection, as well as to look at the marker proteins involved and how the timing of their expression compares to the stumpy form. To do this, fly infections were carried out using monomorphic trypanosomes, which are unable to become stumpy forms, with and without the addition of infection enhancing chemicals. Fly infections with pleomorphic trypanosomes, able to become slender or stumpy, were also carried out with flies of different ages, as these more fully represent flies in the wild. This showed that slender forms can infect tsetse flies in low numbers without additional chemicals, and in both young and old flies. This study further explored the slender to procyclic differentiation process using molecular markers and RNA sequencing, providing evidence that slender forms can directly differentiate to procyclic forms and complete their life cycle within the fly. The second part of this thesis focused on T. congolense, a sympatric trypanosome species responsible for AAT. Unlike T. brucei, T. congolense is monomorphic, possessing only one bloodstream form. This bloodstream form appears to rely on attachment to host red blood cells (RBCs) rather than active motility to survive in the mammalian bloodstream. The attachment mechanism has long been speculated to involve an enzyme called trans-sialidase (TS), responsible for transferring host sugars to the parasite surface. While the importance of TS for T. brucei survival in the tsetse fly and the American trypanosome T. cruzi in its mammalian hosts has been established, the role of TS in T. congolense remains incompletely understood. Therefore, the second objective of this thesis was to carry out preliminary experiments to investigate whether TS is responsible for T. congolense attachment to host cells. This was done by generating TS expressing T. brucei cells and checking for RBC attachment. In summary, this work uncovers greater plasticity in the development of trypanosomes than previously known. The linear life cycle originally ascribed to T. brucei has been challenged, revealing multiple forms that can infect tsetse flies. This change in the life cycle and the investigation of molecular signals involved in this transition have significant implications not only for the basic understanding of the parasite, but also for advancing efforts to eliminate trypanosomiasis. Furthermore, the identification of signals crucial for certain trypanosome species, such as TS, which may operate in different life cycle stages in other trypanosomes, highlights the plasticity of trypanosomes and provides insights into the optimal strategies for combatting the various parasite species contributing to trypanosomiasis.

Periodic shadowing, a concept used in spectroscopy for stray light reduction, has been implemented to improve the temporal contrast of streak camera imaging. The capabilities of this technique are first proven by imaging elastically scattered picosecond laser pulses and are further applied to fluorescence lifetime imaging, where more accurate descriptions of fluorescence decay curves were observed. This all-optical approach can be adapted to various streak camera imaging systems, resulting in a robust technique to minimize space-charge induced temporal dispersion in streak cameras while maintaining temporal coverage and spatial information.

In this paper we study shells of matter and black holes on the expanding bubbles realizing de Sitter space, that were proposed in [4]. We construct explicit solutions for a rigid shell of matter as well as black hole like solutions. The latter of these can also be used to construct Randall-Sundrum braneworld black holes in four dimensions.

We propose a BGK model of the quantum Boltzmann equation for gas mixtures. We also provide a sufficient condition that guarantees the existence of equilibrium coefficients so that the model shares the same conservation laws and -theorem with the quantum Boltzmann equation. Unlike the classical BGK for gas mixtures, the equilibrium coefficients of the local equilibriums for quantum multi-species gases are defined through highly nonlinear relations that are not explicitly solvable. We verify in a unified way that such nonlinear relations uniquely determine the equilibrium coefficients under the condition, leading to the well-definedness of our model.