The Billiard Configuration Space was first introduced by Farber and Tabachnikov to explore the number of periodic billiard trajectories within a smooth, strictly convex domain in Euclidean space. Estimating the Lusternik–Schnirelmann category of the Billiard Configuration Space for a sphere is crucial for establishing bounds on the number of such periodic trajectories. A related concept—topological complexity—was introduced by Farber to address problems in motion planning. Farber, in collaboration with Yuzvinsky and later with Grant, computed the topological complexity of the (standard) Configuration Space in a series of papers. This thesis aims to extend these ideas by providing bounds on the topological complexity and calculating the Lusternik–Schnirelmann category of the Billiard Configuration Space using obstruction theory. Furthermore, we present two Salvetti-type cellular models: the first is applied to compute the fundamental group of the Billiard Configuration Space, while the second allows for the application of obstruction theory.

The first long-distance observations made by Perseverance from the Kodiak butte con- firmed Gilbert-type delta deposition within a closed-lake system in Jezero crater, Mars. Several outcrops at the delta proper were also imaged later during science campaign but their geology and potential relationship to Kodiak needed to be explored. In this thesis, Perseverance image data with a focus on Mastcam-Z and Supercam was used in digital outcrop modeling, applying the Structure-From-motion (SFM) photogram- metry software Agisoft Metashape and georeferenced with SPICE-derived position and orientation. The digital outcrop models (DOMs) were analyzed in the Pro3D software, extracting dip and strike measurements as well as scale bars for determining 2D-clast size-frequency distributions with the ImageJ software. Seven high-resolution, textured and accurate digital outcrop models were created. Evidence gathered from the DOMs shows sedimentary facies associated with Gilbert-type delta stratal architectures. Fore- set and lower foreset facies were identified at the outcrops Franklin Cliff, Whale Moun- tain, Kodiak and Scarp A. Topset facies were found at every outcrop, except Scarp D. “Whale Mountain“ also displays a prominent mouth bar deposit. Six clast samples were collected, all associated with a fluvial origin. Three samples were identified as channel base deposits in a topset environment, one interpreted as a foreset debrite, one debris flow, and one high-energy flood conglomerate. Topset-foreset boundaries differ in alti- tude between outcrops, suggesting different phases of delta progradation. Inferred paleo flows from Whale Mountain and Franklin Cliff link those to the delta strata found at Kodiak, further indicating that the butte was once part of the delta. This thesis demon- strates how digital outcrop models can be used to conduct virtual fieldwork also in the remote environment of Mars.

The relation between Charles Mills and the Enlightenment has often been overlooked or seen as antithetical. Yet Mills considered his philosophy a part of the (black) radical Enlightenment. The latter, he claimed, is true to the core principles of Enlightenment philosophy – objectivism, universalism, and rationalism – but radicalizes them with a focus on actual (racial) socio-political domination. In this paper, I argue that the principles of Enlightenment philosophy play a fundamental role in Mills’s project of locating real-world racial domination and the struggle against it at the center of philosophical reflection. I also show that, according to Mills, only the radical Enlightenment is able to substantively realize these principles. More generally, my discussion sheds light on Mills’s understanding of Enlightenment philosophy and the radical Enlightenment in particular.

A Chinese food network specializing in vegetable crops has existed since the onset of labor migration from southeast China to British Columbia in the 19th century. By 1940, the network achieved market prominence in the local production and distribution of vegetables. This thesis examines the socio-economic history of the network’s emergence and development during the historical period between 1880 and 1940 – the height of white supremacy and discriminatory policies. It seeks to explain how the economic success came about under structural disadvantages. Two theoretical concerns guide the methodologies and historical analysis: How do social relations bear on economic actions? How do migrants interact with the environment in which they find themselves? To deconstruct the narrative that Chinese market gardeners, peddlers, and greengrocers were victims simply pushed into the agri-food sector, this thesis reads for economic difference from data scattered across secondary literature, archival materials, and oral histories. Economic subjectivities and actions are re-aligned to present an alternative picture: small-business entrepreneurship in agriculture as a vehicle to a good life. Adopting mixed embeddedness approach, it traces the interplay between the actors within the network and the structural context of colonialism and capitalism. It identifies the ways in which they utilized resources and devised strategies to adapt to and transform societies. Furthermore, the multifaceted ways in which social relations, especially migrant networks, influenced the emergence and development of the Chinese food network are elaborated.

The biodiversity crisis of rapid species extinction is met with conservation measures on a global scale. The current thesis examines the case of German development cooperation as the biggest financier of biodiversity conservation in the Global South, focusing on the in-volvement of Indigenous Peoples and local communities (IP&LC) in the planning and imple-mentation of biodiversity projects in Bolivia, Colombia, Ecuador, and Peru. Based on inter-views with practitioners in German development cooperation and the protocol of a Bundes-tag hearing it is worked out how German conservation approaches often (still) follow a logic of ecological modernisation. On the other hand, the involvement of IP&LC is gaining sali-ence. By applying a post-colonial political ecology perspective, it is shown that on the imple-mentation level German development actors are aware of the importance of integrating the rights, worldviews and contributions of IP&LC into conservation. However, when it comes to policymaking, IP&LC are often still excluded due to structural obstacles. This bears the risk that IP&LC are merely included for the implementation of Western-designed conservation projects. Conversely, there is a chance that the growing awareness for IP&LC will translate into more participatory conservation that places human well-being at the centre.

Higher-order logic (HOL) offers a simple syntax and semantics for representing and reasoning about typed mathematical concepts. There are many state-of-the-art automated theorem provers for HOL. But the type system of HOL lacks advanced features where types may depend on terms. This is useful as many mathematical notions are inherently dependent typed. Dependent type theory offers such a rich type system but has rather substantial conceptual differences to HOL and isn’t supported as well by automated theorem provers. We introduce a dependently typed extension DHOLP of HOL that supports dependent types while retaining the style and conceptual framework of HOL. Moreover, we describe one translation from DHOLP and a second one from one of its fragments to HOL and prove the soundness and completeness of the translations. We implement both translations within the MMT system—a system for formalizing mathematics—where they are combined with a HOL prover into an automated theorem prover for DHOLP. Finally, we formalize basic set theory notions in DHOLP and outline how such a formalization can be combined with a recent translation of the language of the Mizar proof assistant to MMT to obtain an automated theorem prover for problems in the language of the Mizar proof assistant.

Phosphate homeostasis is essential for survival in eucaryotes. It is mediated by inositol phosphates, which are synthesized by a sequence of kinases. One such kinase in humans is diphosphoinositol pentakisphosphate kinase 2 (PPIP5K2). However, the exact mechanism of phosphate homeostasis in general and PPIP5K2 specifically are still subject to research. To date knockouts and mutations are used for research, but an inhibitor for PPIP5K2 is heavily sought after. Bartsch and Fiedler, who carry out research concerning PPIP5K2, performed a high-throughput screening of 60 000 compounds revealing a single ATP-competitive inhibitor. With an IC50 of 15:5 M the affinity is comparably poor. The presented thesis aims at utilizing computer-aided drug design (CADD) methods to identify additional and ideally more potent PPIP5K2 ligands. We employed the binding mode of the lead compound to perform a pharmacophore-based virtual screening. A second approach deriving pharmacophore features from the PPIP5K2 apo structure was included to broaden the chemical space of potential active compounds further. We wrapped the pharmacophore screenings in a pipeline with additional CADD methods to evaluate the screening hits in more detail. Hits not fitting the binding pocket were discarded first. Then we used molecular docking to place the molecules in the binding pocket and filtered them based on matching the respective pharmacophore hypothesis and on the binding affinity score. Selected hits were simulated using molecular dynamics (MD) and the stability was evaluated by calculating the root-mean-square deviation (RMSD) and fluctuation (RMSF). We identified nine candidates from the lead-based screening and eight from the apo structure-based screening. All candidates conform to their respective pharmacophore, score sufficiently high and are stable in MD simulations. Proposed candidates were handed over to our collaboration partners at FMP and will be tested invitro. If confirmed active, these compounds will aid building a library of PPIP5K2 ligands to be used in research and for further virtual screening and lead optimization campaigns.

Gegen ein allgemein-abstraktes Verständnis ist der spezifisch akademische Antisemitismus zu bestimmen, der sich als Ideologie an das akademische Feld anpasst: So wird Wissenschaftsfreiheit als defensives Individualrecht und die wissenschaftliche Form beansprucht, während sich antisemitische Ressentiments und Wissenschaftsfeindlichkeit zeigen. Die Bedrohung für die Wissenschaftsfreiheit ist aus seiner irrationalen, antagonistischen und spaltenden Logik zu begreifen. Denn er geht mit Täter-Opfer-Umkehr, Leugnungen und weiteren sozialen Abwehrhandlungen einher, die Antisemitismuskritik erschweren und einen verschwörerischen ‚jüdischen‘ Feind imaginieren, der ‚Kritik‘ unterdrücke. Antisemitisch Agierende profitieren von einer organisationskulturellen Neutralität in den deutschen Universitäten, die selten Sanktionen folgen lassen – wenn sie das Problem überhaupt benennen. Denn die institutionelle Selbstregulierung und ihr Ideal der Wissenschaftsfreiheit scheitern an einem systemisch reproduzierten Antisemitismus und einer spiegelbildlichen Selbstidealisierung: Die zumeist liberalen Theorien (hier: Elif Özmen) der Wissenschaftsfreiheit gründen auf den Dualismen wissenschaftlich/ unwissenschaftlich und wissenschaftlich /ideologisch, mit der das Ideologische ausgeblendet wird. Während Özmen auf der Trias von Rechtsstaat, demokratischer Gesellschaft und akademischer Selbstregulierung vertraut, zieht sie keine Konsequenz aus ihrer Erfahrung, dass die meisten Professor:innen bei "Vorfällen“ schweigen. In ihrem Zweckrationalismus, Pragmatismus und Formalismus blendet Özmen von der real unvernünftigen Gesellschaft ab, die systemisch pathisch-projektive Bedürfnisstrukturen, entsprechende Deutungsmuster und mit Alltagsgewalt verbundene strukturelle Angstregime reproduziert. Für Jüdinnen und Juden gehören Universitäten zu jenen Regimen, da im akademischen Milieu mit dem „progressiven“ Ticket, das auf bestimmten schützenswerten, rigiden Gruppenidentitäten gründet, die Widerstandskraft gegen jede Form des Antisemitismus (insb. israelbezogen) schwindet. Indirekt können humanistische Kernmissionen der Akademie (A. Rosenfeld) und ihre Strukturprinzipien (R. K. Merton) Schlimmeres verhindern. Allerdings wäre eine kritische Theorie skeptisch, da jene humanen Missionen und Prinzipien im Antisemitismus als einer „Ontologie der Reklame“ (Adorno) verhöhnt würden. Mehr noch, die ‚Grenzen der Aufklärung‘ stecken in der Wissenschaftsfreiheit selbst: Unter der formalrechtlichen Freiheit kann sich der antisemitische Wahn in wissenschaftlichen Meinungen ‚frei‘ äußern und reproduzieren – das ist der ‚Antagonismus im freien wissenschaftlichen Meinen‘ (in Anlehnung an Adorno). Eine kritische Theorie zielt auf eine antinomische Moralkritik unter den Bedingungen des herrschenden Allgemeinen, die jede sozial und von vernünftigen Zwecken abstrahierende Ethik zur schlechten Unendlichkeit verleiten. Die formale Freiheit zur Wissenschaft bedarf mündiger Subjekte, die diese in bewusster gesellschaftlicher Negativität entfalten und Verfolgte unterstützen. Nicht zuletzt würden sie sich gegen instrumentalisierende Praxisanweisungen stellen und für den Vorrang des zu erkennenden Objekts eintreten, von dem keine unliebsamen Erscheinungen subjektiv abzuwehren sind.

Berlín es reconocida como una de las ciudades más inclusivas y diversas de Alemania, de ahí que se considere como la capital de lo queer-trans*. Aspecto que motivó mi interés personal y académico por comprender de qué manera se inscriben las diferentes identidades en este espacio diaspórico creado en Berlín, y como esta comunidad queertrans* latinoamericana, logra configurarse en un espacio donde ser Queer hace parte de la normalidad. Desde un enfoque interseccional y de género logro profundizar en estas dinámicas y comprender los contextos en que surge la agencia de la diáspora queer y trans* latinx, en relación con su construcción identitaria y su posicionamiento en este nuevo entorno como resultado de su proceso migratorio. Utilizando una metodología cualitativa, exploré los significados otorgados a las prácticas y relaciones migratorias, así como los itinerarios y puntos de inflexión que moldean su experiencia. Se concluye que la agencia surge en contextos de constreñimiento, se caracteriza por ser adaptativa, centrándose en el cuerpo como un espacio de significado y en la interacción constante con el entorno. La creación de un espacio diaspórico, constituye igualmente, una forma de agencia colectiva que proporciona seguridad y les ayuda a enfrentar la pérdida y la expatriación. La capacidad reflexiva y la adaptación al entorno son evidentes, lo que les permite deconstruirse y recrear sus identidades a partir de la configuración de espacios seguros para expresar sus creatividades y resistencias.

Vor dem Hintergrund, dass sich das Schulbildungssystem hin zu einem Ganztagsschulbetrieb wandelt und Lehrer*innen zunehmend zu den ersten persönlichen Ansprechpersonen für Schüler*innen zählen, kommt den Lehrkraft-Lernenden-Beziehungen eine immer größer werdende Bedeutung zu. Viele Lehrer*innen fühlen sich jedoch in Hinblick auf ihren Beratungsauftrag für Schüler*innen und deren Eltern oft überfordert und nicht gut ausgebildet und vermeiden Beratungsgespräche. Als ein wesentlicher Gelingens-Faktor bei Beratungsgesprächen wird die professionelle Haltung und eine entsprechende Selbstwirksamkeit eingeschätzt. Die Methode der Gewaltfreien Kommunikation (GFK) nach Marshall Rosenberg wird als eine Methode empfohlen, die sich besonders gut für Konfliktlösungen eignet. In dieser Arbeit wird untersucht, inwiefern sich die Anwendung der GFK-Methode auf die Haltung und das Selbstwirksamkeitserleben von beratenden Lehrer*innen bei schulischen Konflikt-und Beratungsgesprächen auswirkt. Dazu wurden vier Lehrerinnen interviewt, die von sich angaben eine Ausbildung als Beratungslehrerin absolviert zu haben und die GFK-Methode bei Konflikt- und Beratungsgesprächen anzuwenden. Die Interviewpartnerinnen berichteten, dass sich die Verwendung der GFK positiv auf die professionelle Haltung und das Selbstwirksamkeitserleben auswirkt und beschrieben eine Zunahme an Handlungsfähigkeit in Hinblick auf Konflikt- und Beratungsgespräche.

Terahertz (THz) spectral range covers frequencies from 0.1 to 50 THz [1]. Due to its photon energy, THz radiation is a powerful tool for low-energy excitations. The excitation of spin-waves [2], phonons [3; 4], and ionization of excitons [5] are possible. Additionally, ultrafast spin dynamics can be investigated by the study of THz emission [6]. There are multiple sources to generate THz radiation. Firstly, photoconductive antennas, which are used for linear THz spectroscopy with limited bandwidth <6 THz [7; 8]. Secondly, organic crystals with a bandwidth from 1-10 THz and a major detriment of having gaps in their emission spectrum [9]. Thirdly, the lithium niobate crystal (LiNbO3) with a bandwidth of 0.1-2.5 THz creates high peak amplitudes for non-linear THz spectroscopy [10; 11]. Lastly, the spintronic terahertz emitter covers a range of 0.3-15 THz [12] and was recently improved to match its peak amplitude to the commonly used LiNbO3 [13]. With regards to detection, usually, electro-optic sampling (EOS) using a pump-probe scheme is utilized [14]. With this, a multi-shot approach is used by which the timing between the THz pump and probe is modified to measure the temporal change in the refractive index of the material, which is proportional to the THz amplitude [15]. This approach has some disadvantages. The shot-to-shot fluctuations (noise) of the multiple sampling pulses may easily exceed small signal amplitudes. Therefore, a long averaging time is necessary to obtain an acceptable signal-to-noise ratio. The single-shot EOS (SEOS) could overcome these drawbacks because it requires only one probe pulse to measure the time-resolved change in the refractive index of the material over the whole duration of the THz pulse [17]. This work showcases the successful implementation of a single-shot approach for broadband THz detection. The efficacy of this approach was ascertained through a comparison with the established multi-shot EOS (MEOS) methodology. Furthermore, to gain deeper insights into the underlying dynamics at play, theoretical modeling of the SEOS technique was also carried 3 out. Collectively, these investigations provide a comprehensive understanding of the advantages and limitations offered by the SEOS approach in THz detection.

Sprechen heißt handeln: Auf dem Hintergrund der linguistischen Pragmatik und eines dynamischen Kulturbegriffes untersucht die Arbeit, inwiefern Instagram als heutzutage von Studierenden meistbenutztes soziales Medium eingesetzt werden kann, um die kommunikativ-pragmatische Kompetenz von DaF-Lernenden zu fördern. Kern dieser Masterarbeit ist der Vorschlag kursbegleitender Projekte (Speech acts - Sprechakte, (un)höflich), die DaF-Lernenden pragmatische Aspekte wie Illokutionen und Sozialdeixis näherbringen sowie ihre alltäglichen Lebenserfahrungen zu Beispielen authentischer Kommunikation in der Fremdsprache verwandeln.