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Evaluation der Qualifizierungsreihe „Wie ich bin, bin ich gut!“ - Untersuchung einer Peer-Qualifizierung für Menschen mit Beeinträchtigungen Masterarbeit im Studiengang Psychologie (anwendungsorientiert)
Full text linkIn der vorliegenden Arbeit wird die Qualifizierungsreihe „Wie ich bin, bin ich gut!“ evaluiert,
eine Schulungsmaßnahme für angehende Peer-Berater*innen mit Beeinträchtigungen. Ziel
der Studie war es, die Wirkungen der Qualifizierung aus Sicht der Teilnehmenden zu erfassen
und mögliche Optimierungspotenziale aufzuzeigen. Die Grundlage der Evaluation bilden
sieben qualitative Interviews mit Teilnehmenden, ergänzt durch teilnehmende
Beobachtungen. Die Datenauswertung erfolgte mittels Qualitativer Inhaltsanalyse nach
Mayring mithilfe der Software QCAmap. Die Ergebnisse zeigen, dass die Qualifizierung zum
Empowerment der teilnehmenden Personen und deren Beratungskompetenz beiträgt,
besonders durch den systemischen Ansatz, die Vielfalt der Methoden und das Verhalten und
Eigenschaften der Seminarleiterinnen. Zudem wurde das gemeinsame Lernen von Menschen
mit unterschiedlichen Beeinträchtigungen als besonderes Herausstellungsmerkmal dieser
Qualifizierungsreihe sehr positiv bewertet. Herausforderungen zeigten sich im Umgang mit
Abgrenzung in der Beratungsarbeit und in der Heterogenität der Vorerfahrungen sowie in
strukturellen Rahmenbedingungen der Peer-Beratung. Die Studie gibt Hinweise auf die
Wirksamkeit der Qualifizierung und macht Vorschläge für deren Weiterentwicklung. Zudem
verweist sie auf den Bedarf nach mehr Standardisierung und struktureller Unterstützung in
der bundesweiten Umsetzung von Peer-Beratung
Re-examining Intercultural Competence: Three Case Studies in Chinese Higher Education
Full text linkThe present research aims to re-examine intercultural competence within the context of Chinese higher education. Intercultural competence is regarded as a critical skill in 21st-century China due to the increasingly globalized world, which facilitates interactions among individuals from different countries shaped by different values, beliefs, and experiences. China commenced research on intercultural competence in 2000, with theoretical frameworks originating from abroad. Predominant understandings of intercultural competence in China emphasize the individual, neglecting external factors and not considering these as integral to the role individuals play. Additionally, this perspective overlooks the social action aspects of communication and the outcomes of co-constructed (inter)actions, which are foundational to our comprehension of intercultural competence. Furthermore, intercultural competence is perceived as a tangible reality, encompassing actual experiences of cultural interactions and engagements encountered by individuals from various countries. Interpreting these so-called realities, knowledge, and culture through a static, fixed perspective without recognizing the necessity for interpretation and examination leads to stereotyping and biases. Moreover, the educational system in China presents intercultural knowledge as natural and neutral. However, serving China's strategic policies inherently includes political purposes and ideological elements, resulting in contradictions and conflicts. These contradictions and conflicts are primary sources of the concept's dilemma, confining discussions of intercultural competence in China to the seemingly neutral domains of language and individual skills.
To address these issues encountered by the concept of intercultural competence, I have abandoned the traditional individual-centered approach, instead conceptualizing intercultural competence as a network. I adopted the Actor-Network Theory (ANT), a theoretical framework that provides a unique perspective on intercultural competence. ANT considers and observes all participating actors within an integrated system, including human and non-human elements. It disrupts conventional thinking by encompassing human and non-human actors, prompting a re-examination of intercultural competence. This approach shifts the focus from understanding intercultural competence as an individual-centric concept to examining the relational network and identifying which actors have the potential to act. By moving away the notion that intercultural competence is solely an individual's responsibility, we can understand actors as enacted by the relational network. Their characteristics are determined entirely by the connections within the network; that is, actors derive their capacities and potentials through their relationships with others. This approach prompts us to consider how actors in a network relate to one another
Characterizing the role of Hepatocyte Nuclear Factor 4 in regulating intestinal lipid metabolism in Drosophila
Full text linkPatientenportale als Förderer des Engagements von Patienten mit Diabetes und chronischen Herzerkrankungen: ein Scoping Review zu Nutzung und Usability
Full text linkPatientenportale haben das Potential, die Versorgung chronisch kranker Patienten zu verbessern, indem sie sie in ihre Behandlung einbeziehen. Diese Portale können zum Beispiel als eigenständige Selbstmanagement-Intervention oder als Bindeglied zwischen Gesundheitsanbietern und Patienten in der Routineversorgung funktionieren. Es gibt viele verschiedene Arten von Portalen für unterschiedliche Patientengruppen, die unterschiedliche Funktionen bieten. Ziel dieser Dissertation war es, die aktuelle Literatur zu Patientenportalen für Patienten mit Diabetes mellitus und chronischen Herzerkrankungen hinsichtlich Nutzungsverhalten und Usability zusammenzufassen.
Dieser Review wurde gemäß dem PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) Statement für Scoping Reviews durchgeführt. Es erfolgten Datenbankrecherchen in PubMed, PsycINFO und CINAHL, sowie zusätzliche Suchen in Fachzeitschriften, Reviews und Referenzlisten. In Frage kamen qualitative und quantitative Studien sowie Studien mit beiden Ansätzen, die das Nutzungsverhalten oder die Usability von Patientenportalen analysierten. Die Funktionen der Portale wurden breiten thematischen Kategorien zugeordnet und die Ergebnisse der eingeschlossenen Studien getrennt nach Ergebnis und Forschungsdesign zusammengefasst.
Mithilfe der Auswahlkriterien wurden 85 Studien identifiziert. Die meisten Studien betrafen Patienten mit Diabetes, schlossen Patienten unter 65 Jahren ein und wurden in den Vereinigten Staaten durchgeführt. Die meisten Portale boten bildungs-, überwachungs- und kommunikationsbezogene Funktionen an. Die Studien berichteten über das Nutzungsverhalten einschließlich der zugehörigen Variablen, der Usability und der Verbesserungsvorschläge. Häufig wurde über einen deutlichen Rückgang der Portalnutzung im Laufe der Zeit berichtet. Das Alter wurde am häufigsten im Zusammenhang mit der Portalnutzung untersucht, gefolgt von Geschlecht, Bildung und E-Health-Kompetenz. Jüngeres Alter und höhere Bildung wurden häufig mit einer höheren Portalnutzung in Verbindung gebracht. In zwei Dritteln der Studien, die über die Usability von Portalen berichteten, wurden die Portale als benutzerfreundlich und verständlich eingestuft, obwohl die Messung und Berichterstattung heterogen waren. Die Portale wurden als hilfreich für das Selbstmanagement angesehen, da sie sich positiv auf die Motivation, das Gesundheitsbewusstsein und die Verhaltensänderungen auswirkten. Barrieren für die Portalnutzung waren allgemeiner Art (zum Beispiel Aspekte des Designs oder der allgemeinen Usability), bezogen sich auf bestimmte Situationen während der Portalnutzung (zum Beispiel Anmeldeverfahren) oder waren nicht portalspezifisch (zum Beispiel Fähigkeiten und Präferenzen der Nutzer). Häufige Themen waren Aspekte des Designs, der Usability und der Technologie. Die Verbesserungsvorschläge bezogen sich hauptsächlich auf technische Fragen und den Bedarf an Unterstützung.
Der aktuelle Forschungsstand unterstreicht die Bedeutung der Einbeziehung von Patienten in die Entwicklung und Evaluation von Patientenportalen. Um genauere Aussagen zur Usability treffen zu können und konkrete Schlussfolgerungen für die Praxis abzuleiten, empfiehlt es sich, die vielen unterschiedlichen Bewertungsgrundlagen zu vereinheitlichen oder bereits in die Auswahlkriterien aufzunehmen. Standardisierte Instrumente zur Messung der Usability wären hilfreich, um die Ergebnisse verschiedener E-Health-Interventionen interpretieren und konkrete Schlussfolgerungen ziehen zu können. Zukünftige Forschung sollte sich unter anderem auf das Nutzungsverhalten und die Usability bei älteren Patienten konzentrieren
Pushing and Shaking of Skyrmion Lattices
Full text linkMagnetic skyrmions are topologically non-trivial spin textures that attract great interest, offering a possible avenue towards novel spintronics applications. One of the reasons for it is the small critical current density of about needed to depin the skyrmion lattice. Pinning by disorder remains arguably one of the most important obstacles for all skyrmion-based non-equilibrium experiments and the creation of useful skyrmion devices.
In the presence of a current but in the absence of an oscillating magnetic field, only two phases describe the skyrmion lattice: a pinned phase, where the skyrmions are not moving and an unpinned phase, where skyrmions are moving. We study the unpinning process with the help of slowly oscillating tilted magnetic fields, so-called shaking fields. Strikingly, the depinning happens already at tiny transverse magnetic fields of only a few mT, which corresponds to a small tilting angle of the magnetic field of around 1 degree.
In the first Part of this Thesis, we introduce an elastic model for skyrmion strings in the bulk of a skyrmion-hosting material in the presence of pinning forces under oscillating magnetic fields. We study the dynamics of this system using the Thiele-like approach and provide an analytic solution in the adiabatic limit. Using this model, we predict three phases and find the signatures of phase transitions in the Time-Involved Small Angle Neutron scattering Experiment (TISANE). We examine the unpinning process for different materials, including the metallic systems , with x=0, 0.02, 0.04, 0.06 and the insulator . We find a high degree of universality in the unpinning processes across all these materials.
In the second Part, we study the dynamics within our model under the simultaneous application of a shaking field and an external current. A remarkably rich non-equilibrium phase diagram appears, which includes the so-called "walking" and "running" phases. Strikingly, the critical current density to depin the lattice drops to zero upon shaking the MnSi skyrmion lattice, starting from the critical magnetic field amplitude. Results obtained from this effective model qualitatively reproduce the experimental findings from the transverse susceptibility measurements on MnSi.
In the third Part, we find, from the symmetry analysis of the skyrmion lattice, the periodic magnetic driving schemes under which a directed motion of skyrmion strings becomes possible. We are arguing that counterintuitively, pinning might facilitate a more efficient motion of skyrmion lines.
This Thesis was conducted in close collaboration with Prof. Christian Pfleiderer's group, where most of the relevant experiments were performed. In this Thesis we aim to show that we have acquired important new insights into the nature of pinning in the bulk of skyrmion lattices
Maintenance of mitochondrial DNA integrity in Muscle Satellite Cells
Full text linkMutations in the mitochondrial DNA (mtDNA) have been linked to skeletal muscle atrophy and sarcopenia. Muscle satellite cells (MuSCs), responsible for regenerating new muscle fibres, are generally quiescent but become activated during muscle biogenesis in the course of development and growth, exercise, or damage. The regenerative capacity of MuSCs declines with age, and this is thought to be a contributing factor to sarcopenia. With the ever-increasing age of the global population, it is essential to understand the consequences of disturbed mtDNA integrity in MuSCs in the context of sarcopenia. To explore how mtDNA mutations affect the regeneration capacity of MuSCs, we employed a mouse model expressing a dominant negative mutation of TWINKLE (K320E-Twinkle), the mtDNA helicase, under the control of tamoxifen, specifically in the MuSCs or in skeletal muscle, respectively. This mutation is known to accelerate the accumulation of mtDNA alterations. Acute activation of muscle regeneration in adult mice by cardiotoxin induced degeneration of M. tibialis anterior (TA) induced the dramatic accumulation of fibres with mitochondrial dysfunction and enhanced inflammation. Our studies using the mitoTIMER reporter, along with induction of K320E-Twinkle in MuSCs in vitro, pointed to an initial increase in mitochondrial biogenesis and turnover. In contrast, when K320E-Twinkle is activated upon muscle biogenesis during normal development, we do not observe mitochondrial dysfunction. However, histological analyses showed a reduced cross-sectional area and a prominent fibre type shift, from glycolytic to oxidative in the TA. Interestingly, this was observed only in the glycolytic TA muscle and not in the predominantly oxidative M. soleus. Additionally, in vitro analysis of MuSC differentiation showed that K320E-Twinkle impairs muscle fibre differentiation by reducing mitochondrial biogenesis. Accordingly, K320E-Twinkle-C2C12 cells also showed disturbed differentiation, along with reduced myogenic fusion, respiratory chain defects, and progressive mtDNA depletion. Proximity proteomics revealed a decrease of mitochondrial proteins in the proteome of the mutant cells. In conclusion, our results demonstrate that interfering with mtDNA replication in MuSCs impairs muscle differentiation and alters muscle architecture. Our data reveals a link between mtDNA integrity and the altered metabolic shift from glycolytic to oxidative, similar to that observed in aged sarcopenic muscle of long-lived organisms
Quantification of echo intensity in fascicle-aligned ultrasound: ex-vivo validation of spatial gain sonography
Full text linkThe breadth of functions attributed to muscle has only recently been grasped, augmenting it from mere body locomotor to important metabolic and endocrine organ. Its structure, supported by intramuscular connective tissue, is cause and consequence of many functional changes in the muscle. Each muscle fiber is surrounded by endomysium; perimysium in turn engulfs several muscle fibers forming a fascicle. Epimysium forms the outermost layer of a muscle and is also known as fascia in clinical contexts. In pennate muscles, fascicles are not parallel to the epimysium but lie at an angle allowing for more force to be generated per muscle cross-sectional area. Changes of intramuscular connective tissue are difficult to track in a non-invasive and inexpensive way. While ultrasound offers a chance to do so, it lacks reliability as each measurement is highly dependent on operator and subject variables such as probe tilt, ultrasound device settings, muscle pennation angle and subcutaneous fat layer.
Ultrasound waves are emitted from a probe and travel through connective tissue and muscle at different speeds of sound. At each tissue interface a portion of them is reflected to the probe. B-mode ultrasound images consist of pixels of different gray values determined by the sound energy received at the probe, which is also called echo intensity.
Echo intensity in muscle increases with age and immobilization, but also in muscular dystrophy, which may be attributed to muscle atrophy and denser intramuscular connective tissue under these circumstances. This relationship allows for tracking muscle quality with ultrasound and eventually could help with early detection of muscle pathology. However, echo intensity decreases with increasing pennation angle if not corrected for. Similarly, different probe tilts lead to differing echo intensities, i.e., a low inter-rater reliability. This study aimed to establish a relationship between the insonation angle and echo intensity in order to mathematically integrate this relationship in future measurements or even implement it in future devices.
From the laws of specular reflection, we hypothesized (1) that the highest echo intensity would result from a perpendicular insonation of muscle fascicles, i.e., with the probe parallel to the fascicle. The mean gray value (MGV) of the ultrasound image at 0° of fascicle probe angle (FPA) would then be comparable between muscles without the bias of probe tilt or pennation angle. Next, we hypothesized (2) that the relationship between MGV and FPA could be mathematically modeled and (3) that this would result in a trigonometric function.
51 muscles of Bos taurus from overall 10 different anatomical locations were scanned post-mortem at 5 different insonation angles using an angulated ultrasound gel pad. The ultrasound scans were obtained in longitudinal orientation to the fascicles with the skin, subcutaneous fat and the superficial fascia removed. All ultrasound settings remained constant throughout measurements. Pennation angle, tilt angle of the probe and mean gray value in a region of interest were measured, the relationship between FPA and MGV was analyzed and the slope of the linear function for each muscle was calculated (tilt echo gain; TEG).
Computation of FPA to MGV revealed a sinusoidal fit, confirming hypotheses 2 and 3. At smaller FPAs the relationship could be modeled with a linear fit with high enough accuracy. The linear fit was used for further calculations as it would be more user-friendly in the clinical setting. We found that MGV was indeed highest at an FPA of 0° for every muscle aligning with our first hypothesis. Both MGV at 0° FPA (MGV_00) and TEG showed muscle-specific differences. They also behaved differently across muscles indicating that they reflect different features of muscle architecture. In mixed effect models age was significant for MGV_00.
Limitations of this study include the unknown effect of internal image processing of the ultrasound software which is inherent to all commercial scanners. Changes in echo intensity could also have been caused by employing an ultrasound gel pad resulting in a slight variability in scanning depth. However, no significant muscle-specific effects were detected for the depth of the region of interest suggesting that scanning depth did not affect the results. While new parameters for measuring echo intensity were found in this study, it cannot be determined whether MGV_00 and TEG correlate with the amount of IMCT, which is a topic of ongoing research. Finally, age could only be made available for part of the animals resulting in limited validity of the data regarding the relationship between age and MGV_00.
This study established and validated a new method to quantitatively measure echo intensity in muscles using angulation, from here on referred to as spatial gain sonography. MGV_00 and TEG serve as more objective parameters than echo intensity alone, especially with regards to probe tilt, and might serve as new muscle-specific variables to compare between or track muscle echo intensity over time. This will allow for future muscular ultrasound studies to be more comparable and is one step in the necessary standardization towards reliable ultrasound diagnostics of musculoskeletal pathologies
The Role of the Motivational Brain in Parkinson’s Disease: A Multimodal Neuroimaging Approach
Full text linkParkinson's disease (PD) is a progressive multi-system neurodegenerative disease that affects approximately 2% of the population over the age of 80. The accelerated increase in prevalence with age, combined with the rapid aging population in Europe and other Western regions, is leading to a dramatic increase in the (social, economic and personal) burden of PD. Accordingly, there is an urgent need for a better understanding of the disease. So far, almost 200 years of research have yielded significant insights into the pathophysiology of PD. While the precise mechanisms between pathology and clinical presentation are incompletely understood, recent evidence points to a motivational influence on PD motor symptoms. This cumulative thesis aims to investigate the importance of the motivational brain in PD and its associations with PD motor symptoms. To address this aim, this thesis is comprised of three individual research projects, each guided by a different perspective, ultimately addressing the overall research question.
The objective of the first project is to provide an overview of the current literature on neuropathological changes in motivational brain regions and their associated clinical manifestations in PD. The study showed that pathological changes can be observed early on, with some alterations being related to PD motor symptoms. The second project aims to further elucidate the underlying mechanism of motivational contributions to PD motor symptoms. Interestingly, this project showed that the loss of effortful movements may be based on a reduced implicit motivation to move, suggesting that PD motor symptoms may not be a purely motoric issue. Finally, in the third project, it is investigated whether patients can be divided into subtypes based on their observed neurodegeneration in the motivational brain, more specifically the amygdala. However, although the motivational brain seems to play a role in PD motor symptoms, the results of this project suggest that it does not seem to aid classification.
Taken together, the research projects included in this thesis provide an in-depth understanding of the role of motivational brain regions in PD. Collectively, they highlight the far-reaching consequences of neurodegenerative changes that go beyond non-motor symptoms and also contribute to the cardinal motor impairments. In doing so, this work highlights the importance of including motivational brain regions in the scientific discourse and encourages further investigation to promote a better understanding of the disease. Finally, the knowledge gained may contribute to the development of novel therapeutic strategies with the ultimate goal of alleviating the burden of PD
Exploring Matter-Antimatter Asymmetry in a Rotating Universe
Full text linkThis thesis investigates the potential role of spatial anisotropies and global rotation in
addressing the observed matter-antimatter asymmetry in the universe.
The standard cosmological model, ΛCDM, faces several unresolved puzzles, in-
cluding CMB anomalies, dark matter, and the matter-antimatter asymmetry. The
CMB anomalies suggest deviations from isotropy, prompting the exploration of more
general anisotropic models. Additionally, current solutions to dark matter and matter-
antimatter asymmetry imply the need for extensions beyond the Standard Model.
Given these issues, it is crucial to question the accuracy of the FLRW geometry in
ΛCDM. This thesis explores the rotating Bianchi IX universe, motivated by the BKL
conjecture and the potential role of global rotation in cosmological angular momentum
generation, in an effort to investigate the anisotropic effects of geometry on the particle
spectrum.
The Weyl and Dirac spinor fields are studied within the Bianchi IX universe, con-
sidering a range of models, from the axisymmetric Bianchi IX universe to the more
general rotating Bianchi IX model. The Hamiltonian for spinor fields in this back-
ground is formulated, and the corresponding equations of motion for Weyl and Dirac
spinors are derived. The field equations are solved in a fixed background as an initial
step toward understanding the particle spectrum in such spacetimes. This approach
sets the stage for future refinements using the adiabatic approximation and the WKB
approximation. Generalized spinor spherical harmonics are obtained using analogies
with the asymmetric “ideal” top. Building on previous work on the diagonal Bianchi IX
model, we generalize this approach for spinor fields in a broader Bianchi IX framework.
Our work builds on earlier studies of Weyl spinors and the phenomenon of level
crossing, which results in the creation of neutrinos instead of antineutrinos in an ax-
isymmetric Bianchi IX universe as the universe evolves toward isotropy. We extend
this analysis to a broader class of models, examining how these effects manifest in more
general rotating and anisotropic cosmological backgrounds. While Weyl fermions do
not describe neutrinos in nature, the mathematical framework developed here is useful
for analyzing the Dirac equations in this context.
For Dirac fermions in the axisymmetric Bianchi IX model, we find that the energy
spectrum is significantly influenced by the spin orientation, resulting in spin-dependent
enhancements or suppressions for both particles and antiparticles. The inclusion of
global rotation introduces further contributions due to the coupling between particle
spin and the universe’s rotational motion. Specifically, rotational contributions to the
energyspectrumcauseenergyshiftswithoppositeeffectsforparticlesandantiparticles.
Depending on the alignment of the spin with the universe’s rotation, energy levels are
either increased or decreased, leading to complex modifications in the energy structure.
This spin-angular velocity coupling uncovers previously unexplored mechanisms that
could contribute to the observed asymmetry between matter and antimatter—effects
absent in homogeneous and isotropic models.
Therefore, these results underscore the importance of background anisotropies in
the search for an explanation of the matter-antimatter asymmetry and encourage fur-
ther investigation in this direction. The next logical step in this research is to solve
the equations in a time-dependent background, beginning with the adiabatic approx-
imation and later employing the WKB approximation to account for more realistic
conditions. Furthermore, the analysis could be extended to include interactions within
quantum electrodynamics (QED), enabling the exploration of whether these geomet-
ric effects influence particle creation and annihilation processes. These efforts could
provide valuable insights into the role of geometric effects in fundamental interactions,
contributing to our understanding of the mechanisms driving the matter-antimatter
asymmetry in the Universe
