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Wie hängen „Work Logics“, Vorstellungen gesellschaftlichen Zusammenhalts und politische Orientierungen zusammen? : Studienreport
No full textDieser Studienbericht beschreibt die qualitative Studie "Work Logics" die im Rahmen des Forschungszentrums Gesellschaftlicher Zusammenhalt (FGZ) an der Universität Bremen durchgeführt wurde. Das Forschungsprojekt untersuchte Zusammenhänge zwischen sog. Work Logics (Oesch 2006a; 2006b), Vorstellungen gesellschaftlichen Zusammenhalts und politischen Orientierungen. Hierfür wurden in den Jahren 2023 und 2024 insgesamt 8 Gruppendiskussionen mit 7 verschiedenen Berufsgruppen (Lehrer:innen, Pastor:innen, Servicemitarbeiterinnen, Verwaltungsangestellte, Klinikclowns, Ingenieur:innen, Unternehmer:innen) durchgeführt. In den Gruppendiskussionen stand das subjektive Erleben der gesellschaftlichen und politischen Entwicklungen der letzten Jahre im Zentrum. Exmanente Fragen thematisierten die Themenbereiche Zusammenhalt, Politik und Staatlichkeit, eigenes Handeln sowie Partei- und Politikpräferenzen, um die Orientierungsrahmen und Problemlösungsstrategien der unterschiedlichen Berufsgruppen zu rekonstruieren. Der archivierte Datensatz bietet Nachnutzungspotenziale im Bereich der Arbeitssoziologie, politischen Soziologie oder Sozialstrukturanalyse.Bundesministerium für Bildung und Forschung (BMBF
Migration von subsaharischen Flüchtlingen nach Deutschland und Frankreich – Ursachen und Integrationssituationen
No full textDie Arbeit befasst sich mit der Migration von subsaharischen Flüchtlingen nach Deutschland und Frankreich und ihrer Lebenssituation dort. Die hauptsächlichen Fragestellungen, die dabei verfolgt werden, lauten: Welches sind die Ursachen und wie ist der Verlauf von Migrationen der Flüchtlinge aus Subsahara-Afrika in die Aufnahmeländer? Wie sehen die Lebens- und Integrationssituationen der subsaharischen Flüchtlinge in Deutschland und Frankreich aus?
Diese Fragen werden anhand von Fallstudien für aus Subsahara-Afrika stammende Flüchtlinge in Deutschland und in Frankreich untersucht. Im Mittelpunkt stehen die Fragen nach den Verläufen und Ursachen der Migrationen nach Europa, nach den Rahmenbedingungen, unter denen subsaharische Flüchtlinge in den Aufnahmeländern leben, nach den Möglichkeiten, die sich ihnen dort bieten, sowie nach den unterschiedlichen Handlungsoptionen bzw. Überlebensstrategien, die sie entwickelt haben, um den täglichen Bedürfnissen des Lebens in einem fremden Land gerecht zu werden.
Darüber hinaus wird die Integrationssituation der Flüchtlinge in den Aufnahmeländern untersucht. Ein wesentlicher Schwerpunkt liegt dabei auf ihr jeweiliges Bürgerbewusstsein gelegt werden
Unidirectional sensing via dual-sensitivity bi-axial flexible sensors. Based on electrically aligned carbon nanotube nanocomposites
No full textImagine a regular flexible pressure sensor that can be integrated inside a host material (e.g. an industrial sealing) to measure the applied pressure. With pressure, the sensor changes its vertical dimensions and changing its intrinsic resistance. However, aside from the vertical change, the pressure also causes lateral strain in the sensor, changing its outer dimensions and affecting the measurement value of the sensor. A possibility to minimize this cross-sensitivity is by creating unidirectional sensitive sensors. A sensor that only response to a force from a single direction, and is insensitive to all other.
This research presents the fabrication and characterization of flexible polymer-based sensors that can measure externally applied pressures and forces. A polymer substrate is implemented as a substrate to ensure its flexibility. Carbon nanotubes (CNTs) are integrated in the polymer to achieve a piezoresistive polymer. The working principle follows the fact that with an externally applied pressure, the polymer volume decreases, effectively decreasing the distance between individual CNTs. This in turn increases the composites conductivity, which can be measured.
This work is divided into two major parts: flexible sensors with integrated carbon nanotubes that are either randomly dispersed within the polymer or aligned by means of an electrical field. The dissertation goes through all fabrication steps of dispersing the carbon nanotubes in the polymer, and the different available methods. Afterwards, the first strain and pressure results are shown with the two chosen polymers: Polydimethylsiloxane (PDMS) and Polyimide (PI). The advantages of both polymers and sensor types are discussed, followed by the introduction of the possibility to decrease the cross-sensitivity of the sensors by aligning the carbon nanotubes in the polymer before it is cured.
The principle of the induced dipole moment within the CNT, causing the rotation in the presence of an electric field is highlighted. Numerical and analytical models are included to support the experimental results found in this research. The possibility of creating highly sensitive piezoresistive sensors based on aligned carbon nanotubes is attributed due to the electron tunneling effect. Carbon nanotubes that are within a few nanometer can ‘tunnel’, jumping over a short distance of non-conductive material. The resistance of such connections increases exponentially with distance, giving rise to highly sensitive sensors with Gauge factors up to 10^3 found in this research. The aligned PDMS-based sensors show a high degree of alignment, which can be even improved further by utilizing functionalized carbon nanotubes. Experiential results show a greater strain region for the sensor, and more controllable and connected carbon nanotube alignment.
Finally, the randomly CNT-oriented and stable polyimide pressure sensors are integrated into rubber sealings in order to monitor the condition and applied pressure on the sealings
Competitive Query Minimization for Stable Matching with One-Sided Uncertainty
No full textWe study the two-sided stable matching problem with one-sided uncertainty for two sets of agents A and B, with equal cardinality. Initially, the preference lists of the agents in A are given but the preferences of the agents in B are unknown. An algorithm can make queries to reveal information about the preferences of the agents in B. We examine three query models: comparison queries, interviews, and set queries. Using competitive analysis, our aim is to design algorithms that minimize the number of queries required to solve the problem of finding a stable matching or verifying that a given matching is stable (or stable and optimal for the agents of one side). We present various upper and lower bounds on the best possible competitive ratio as well as results regarding the complexity of the offline problem of determining the optimal query set given full information.17:117:2
„Masstige Marketing“ – Über die Relevanz eines neuartigen Phänomens für die identitätsbasierte Führung von Luxusmarken
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In vivo study of the role of the chaperone HSP110 in amyloid beta (Aβ) aggregation
No full textProtein misfolding and aggregation are characteristic events in most neurodegenerative diseases. To prevent proteotoxicity, the cell has evolved a protein homeostasis (proteostasis) network comprised of molecular chaperones and proteolytic pathways. Molecular chaperones can regulate protein folding by e.g. prevention of protein aggregation, refolding of proteins and protein disaggregation. Molecular chaperones can be used as targets for pharmacological intervention against neurodegenerative diseases. HSP110 is a poorly characterised molecular chaperone and its functional spectrum is not yet fully elucidated. Nevertheless, HSP110 has recently been implicated in various neurodegenerative diseases, including Alzheimer´s disease (AD). Aggregation of the amyloid beta peptide (Aβ) is one of the hallmarks of AD. In vitro studies have shown that human HSP110 can inhibit Aβ1-42 fibril formation either alone or in combination with HSC70 and a J-domain protein. However, the beneficial versus detrimental implications of HSP110 in neurodegenerative physiological contexts are still under debate.
Therefore, I investigated the effect of HSP-110 and its interplay with Aβ1-42 in vivo using C. elegans as a model organism. I generated a novel C. elegans model that overexpressed hsp-110 pan-neuronally and I also depleted hsp-110 by RNAi-mediated knockdown. I analyzed the role of HSP-110 in Aβ1-42 aggregation using a pan-neuronal Aβ C. elegans model. In addition, I performed transcriptomic and proteomic analyses of pan-neuronal and muscular Aβ C. elegans strains to reveal global changes in gene expression and protein levels in these AD models. I could show that hsp-110 overexpression exacerbated Aβ1-42 aggregation in vivo. Conversely, hsp-110 depletion reduced Aβ1-42 aggregation significantly in the IL2 neurons, which mark the onset of Aβ1-42 aggregation in C. elegans. Moreover, HSP-110 is a modulator of the autophagy pathway, with overexpression of hsp-110 impairing and depletion of hsp-110 inducing autophagy. HSP-110 appears to regulate multiple nodes of the proteostasis network and further studies are necessary to fully unravel the effect on Aβ1-42. In addition, I gained a preliminary understanding of the biological changes associated with Aβ1-42 aggregation in C. elegans using transcriptomic and proteomic analyses. Surprisingly, of the molecular chaperones, only small HSPs showed an increased abundance
Influence of international organisations on social policy making in vulnerable countries: The case of Croatian healthcare financing policy
No full textThis dissertation investigates the influence of international organisations (IOs) on healthcare financing policy in Croatia, focusing on the period from 1990 to 2019. It analyses how IOs prescribe and interact with domestic policymakers. The central argument of the dissertation is that while IOs play a significant role in shaping healthcare financing policy, their influence is not absolute. The findings challenge perceptions of IOs, particularly the World Bank, as inflexible and hegemonic actors able to unilaterally impose policies on vulnerable countries. Instead, the dissertation emphasises their capacity for pragmatism and cooperation in the policy transfer process. The thesis argues that this approach is driven by a combination of factors, including a desire to promote development in aid-recipient countries and a self-interest in maintaining a long-term relationship that facilitates future lending and influence
School-Parent-Communication as a Question of Attitude
No full textFür eine gelinge Zusammenarbeit zwischen Schule und Eltern ist Kommunikation unerlässlich. In dieser Kommunikation sind Schulen dazu aufgefordert, die vielfältigen Bedürfnisse und Voraussetzungen von Eltern in der Migrationsgesellschaft zu berücksichtigen. Wie dies gelingen kann, stellt sich eher als eine Haltungs- und nicht als Methodenfrage heraus. Zentral sind z.B. frühzeitige und proaktive Kontakte zum Aufbau von gegenseitigem Verständnis, die Anerkennung der Orientierungs- und Informationsfunktion von Schule sowie die Kooperation mit Schlüsselpersonen und -organisationen auch aus migrantischen Communities
Method development for the DFT calculation of charge-assisted surface reactions in a periodic model
No full textMany important processes of great technological importance can be modeled by properly designed charged systems. A common example is photocatalysis, where photon absorption promotes electrons from the valence band of a semiconductor photocatalyst to its conduction band, generating electrons and holes. Density functional theory is widely used for investigating the properties of defects in bulk and on the surface of solids. However, Local or semi-local approximations in the density functional may cause incorrect occupation of defect states and incorrect formation energies. These methods also underestimate the localization of defect states, missing the formation of small polarons.
I show that, by making the atom- and angular-momentum-dependent parameters of the Lany-Zunger polaron correction also coordination-dependent, it is possible to correctly describe charge trapping in small polaron states on the anatase (101) and rutile (110) surfaces at a low computational cost.
I implemented Komsa and Pasquarello correction scheme for charged models in a user-friendly code and extended the method to handle mediums with anisotropic dielectric tensors as well as cases where the extra charge is localized at multiple sites. In slab models with a large vacuum between the layers, a posteriori charge correction methods may not be adequate, and self-consistent correction may be needed to eliminate the spurious effects. I introduce a self-consistent potential correction method, co-developed by myself, that is capable of dealing with those cases.
Finally, I use the developed framework to investigate the photocatalytic CO oxidation on the anatase (101) surface. For the restoration of the pristine surface, I propose a mechanism to eliminate the surface oxygen vacancies by including electron-scavenging oxygen molecules in the gas phase. With the proposed mechanism, it is possible to achieve a complete catalytic cycle for the oxidation of CO over the anatase (101) surface
Unsupervised deep machine learning methods to discriminate icequakes in seismological data from Neumayer Station, Antarctica
No full textUnsupervised machine learning methods are gaining attention in the seismological community as more and larger datasets of continuous waveforms are collected, since they tackle the chal- lenging task of learning without using hand-labelled data. In this thesis, we present some neural network approaches to the task of unsupervised learning, and apply them to discriminate and cluster different seismological events, including icequakes and earthquakes. We focus mainly on contrastive learning, which has recently been showing great success in the field of computer vision and other domains, and we transfer these methods to the domain of seismology. We implemented and tested data augmentation strategies for seismological data, and applied the contrastive learning method SimCLR as well as the deep clustering method DEC. For this pur- pose, we created and partially labelled different datasets containing various waveforms including many icequakes detected by an STA/LTA algorithm on continuous waveform recordings from the geophysical obervatory at Neumayer station, Antarctica. We demonstrate the effectiveness of our approach using quantitative evaluation on the labelled dataset as well as qualitative evaluation of the clustering on a larger unlabelled dataset