Ein lokaler Beweis der Breuil-Mézard-Vermutung im Falle skalarer Halbvereinfachung

Das Hauptresultat der Dissertation ist ein lokaler Beweis der Breuil-Mezard-Vermutung im Falle einer stetigen 2-dimensionalen reduziblen Darstellung der absoluten Galoisgruppe von Qp mit skalarer Halbvereinfachung. Dabei benutzen wir einen allgemeinen Formalismus von Vytautas Paskunas, den wir in unserem Fall vereinfachen. Ausserdem geben wir eine explizite Darstellung der nichttrivialen universellen gerahmten (framed) Deformationsringe an, die crystalline Lifte der residualen Darstellung mit fixiertem Hodge-Typ und kleinen Hodge-Tate-Gewichten parametrisieren. Damit koennen wir zeigen, das die speziellen Fasern dieser Ringe geometrisch irreduzibel und generisch reduziert und ihre Hilbert-Samuel-Multiplizitaeten entweder 1, 2 oder 4 sind. In den letzten beiden Faellen sind die universellen Ringe nicht Cohen-Macaulay.The main result of this dissertation is a local proof of the Breuil-Mezard conjecture in the case of a continuous 2-dimensional reducible representation of the absolute Galois group of Qp with scalar semi-simplification. To prove this we use a general formalism of Vytautas Paskunas, that we simplify in our case. Moreover, we give an explicit presentation of the non-trivial deformation rings that parameterize crystalline lifts of the residual representation with fixed Hodge type when the Hodge-Tate weights are small. Thereby we can show that the special fibers of these rings are geometrically irreducible and generically reduced and that their Hilbert-Samuel multiplicities are either 1, 2 or 4. In the last two cases the universal rings are not Cohen-Macaulay

Die höhere Berufsbildung in der Schweiz. Strukturelle Determinanten des Übertritts und langfristige Erträge

Die höhere Berufsbildung stellt etwa ein Drittel aller Absolventen auf tertiärem Bildungsniveau in der Schweiz. Als Zulassungsvoraussetzung gilt meist eine abgeschlossene berufliche Grundbildung mit eidgenössischem Fähigkeitszeugnis und Berufspraxis. Das Dissertationsprojekt untersucht, wie individuelle und strukturelle Aspekte den Übergang in die höhere Berufsbildung bestimmen. Zudem ist die Schätzung langfristiger Lohnrenditen und die Erklärung von Renditeunterschieden nach einer HBB zwischen Berufsgruppen von Interesse. Abschliessend werden Bestimmungsgründe beruflicher (Lohn)Mobilität von HBB Absolvierenden und AkademikerInnen über den Erwerbsverlauf untersucht.In Switzerland, holders of professional qualifications account for roughly one-third of all holders of tertiary-level qualifications. In most cases, admission to professional education is open to holders of a Federal VET Diploma who have the requisite amount of work experience. This dissertation project examines individual and structural aspects influencing the transition to professional education. It further focuses on long-term private monetary returns to professional education and provides an explanation of respective differences in income levels between professional groups after completion of professional education. Finally, the determinants of professional (income) mobility over the course of one’s career for both holders of professional education qualifications and holders of higher education qualifications are explored.Parmi l’ensemble des personnes diplômées du niveau tertiaire, environ un tiers se prévaut d’une formation professionnelle supérieure. Pour être admis, il faut en général avoir achevé une formation professionnelle initiale sanctionnée par un certificat fédéral de capacité et avoir acquis une expérience pratique du monde du travail. Ce projet de thèse examine de quelle manière les aspects individuels et structurels déterminent la transition vers la formation professionnelle supérieure. L’estimation des rendements salariaux à long terme revêt également un intérêt, tout comme l’explication des différences de rendements entre les groupes professionnels après une telle formation. Il s’agit enfin de se pencher sur les facteurs de détermination de la mobilité (des salaires) au fil de la carrière des personnes ayant suivi une formation professionnelle supérieure ou un cursus universitaire

Anonymity in Bitcoin? – The Users’ Perspective

This article analyzes how users perceive the degree of anonymity provided by the Bitcoin network, to what extent they are concerned about anonymity when using Bitcoin, whether they are knowledgeable of and concerned about specific de-anonymization attacks, and if they are aware of and adopt privacy-preserving countermeasures. A user survey with 125 active Bitcoin users reveals that 70% associate a medium or high level of anonymity with the Bitcoin network and rate their concerns as either low or medium. But almost every 5th user has already considered abandoning Bitcoin because of being concerned about anonymity. Though one third are aware of the risk of de-anonymizing the Blockchain but are not concerned, another almost 50% indeed feel concerned. Our findings have implications for users and developers, suggesting that actions should be undertaken to increase privacy awareness and the level of anonymity provided by the Blockchain and the Bitcoin network

Medium and Long-Term Returns to Professional Education in Switzerland: Explaining Differences between Occupational Fields

In Switzerland, initial vocational education and training graduates may enter a track of the tertiary system called professional education. Professional education represents about one-third of the tertiary system, includes numerous vocational training courses, and prepares for managerial or expert positions. Despite its prevalence, the long-term returns to professional education have rarely been investigated due to lacking data. In order to fill this gap, we will estimate the long-term returns to professional education based on a novel methodological design. Secondly, we aim to explain the differences in the returns to professional education between occupational fields by making use of the task-based approach of Autor, Levy and Murnane (2003). Analyses are based on the Swiss Labour Force Survey from 1991–2016. Based on a quasi-panel with cohort fixed effects and on linear regression models, our results reveal average short-term returns to professional education of 7% and long-term returns of 11%. However, we find considerable differences in the returns between training fields, which can partly be attributed to differences in the change of task composition after completion of professional education between occupations

Nanoscale Near-Field Tomography of Surface States on (Bi(0.5)b(0.5))(2)Te-3

Three-dimensional topological insulators (TIs) have attracted tremendous interest for their possibility to host massless Dirac Fermions in topologically protected surface states (TSSs), which may enable new kinds of high-speed electronics. However, recent reports have outlined the importance of band bending effects within these materials, which results in an additional two-dimensional electron gas (2DEG) with finite mass at the surface. TI surfaces are also known to be highly inhomogeneous on the nanoscale, which is masked in conventional far-field studies. Here, we use near-field microscopy in the mid infrared spectral range to probe the local surface properties of customtailored (Bi0.5Sb0.5)(2)Te-3 structures with nanometer precision in all three spatial dimensions. Applying nanotomography and nanospectroscopy, we reveal a few-nanometer-thick layer of high surface conductivity and retrieve its local dielectric function without assuming any model for the spectral response. This allows us to directly distinguish between different types of surface states. An intersubband transition within the massive 2DEG formed by quantum confinement in the bent conduction band manifests itself as a sharp, surface-bound, Lorentzian-shaped resonance. An additional broadband background in the imaginary part of the dielectric function may be caused by the TSS. Tracing the intersubband resonance with nanometer spatial precision, we observe changes of its frequency, likely originating from local variations of doping or/and the mixing ratio between Bi and Sb. Our results highlight the importance of studying the surfaces of these novel materials on the nanoscale to directly access the local optical and electronic properties via the dielectric function

Reported and recorded sleepiness in obesity and depression

Civil war, flight, escape and expulsion are extremely stressful and assert a negative impact on refugees’ mental health. However scientific research about resilience and coping of refugees is scarce. Especially in the recent refugee crisis, calls have been made to consider factors contributing to coping and resilience in this vulnerable population. Therefore, the current research sought to investigate individual differences that could serve as antecedents of coping and contextual factors that might moderate these effects. Specifically, it took into account individual’s self-regulatory differences in terms of regulatory focus (i.e., a promotion focus on nurturance needs, ideals and gains vs. a prevention focus on security needs, oughts and losses). It furthermore explored contextual influences by considering Syrian refugees in Turkey (Sample 1, N = 273) and Germany (Sample 2, N = 169). Compared to Syrian refugees in Turkey, those in Germany had a stronger promotion focus. They also reported more problem-focused and less maladaptive coping, as well as less symptoms. Both promotion and prevention focus were positively related to problem-focused coping. Problem-focused coping, in turn, predicted more symptoms in Turkey but not in Germany. Furthermore, a stronger promotion focus was associated with less symptoms and maladaptive coping was associated with more symptoms in both samples. These results contribute to the coping literature in demonstrating that under certain conditions problem-focused coping can be maladaptive and extend the scarce previous work on self-regulation and coping. Most importantly, they highlight a promotion focus as a clear resilience factor and the role of maladaptive coping in increasing vulnerability. As such, they might inform the design of effective interventions among Syrian refugees and beyond

Clumping and X-Rays in cooler B supergiant stars

B supergiants (BSGs) are evolved stars with effective temperatures between 10 to 30 kK and are important to understand massive star evolution. Located on the edge of the line-driven wind regime, the study of their atmospheres is helpful to understand phenomena such as the bi-stability jump. Key UV features of their spectra have so far not been reproduced by models for types later than B1. Here, we aim to remedy this situation via spectral analysis that accounts for wind clumping and X-rays. In addition, we investigate the evolutionary status of our sample stars based on the obtained stellar parameters. We determined parameters via quantitative spectroscopy using CMFGEN and PoWR codes. The models were compared to UV and optical data of four BSGs: HD206165, HD198478, HD53138, and HD164353. We also study the evolutionary status of our sample using GENEC and MESA tracks. When including clumping and X-rays, we find good agreements between synthetic and observed spectra for our sample stars. For the first time, we reproduced key lines in the UV. For that, we require a moderately clumped wind (f_infty > ~0.5). We also infer relative X-ray luminosities of ~10^-7.5 to 10^-8 -- lower than the typical ratio of 10^-7. Moreover, we find a possible mismatch between evolutionary and spectroscopic masses, which could be related to the mass-discrepancy problem present in other OB stars. Our results provide evidence that X-rays and clumping are needed to describe the winds of cool BSGs. However, their winds seem less structured than in earlier type stars. This aligns with observational X-rays and clumping constraints as well as recent hydrodynamical simulations. The BSGs' evolutionary status appears diverse: some objects are potentially post-red supergiants or merger products. The wind parameters provide evidence for a moderate mass-loss rate increase around the bi-stability jump. Abstract abridgedComment: 27 pages, 22 figures, accepted for publication in A&