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Scherwellenelastographie des muskuloskelettalen Gewebes der unteren Extremität im Leistungssport
No full textDie Gewebesteifigkeit von Sehnen und Muskeln der unteren Extremität spielt eine zentrale Rolle für Leistungsfähigkeit, Belastbarkeit und Verletzungsanfälligkeit im Leistungssport. Mithilfe der sonographischen Scherwellenelastographie lassen sich mechanische Eigenschaften muskuloskelettaler Strukturen nicht-invasiv und quantitativ erfassen. Ziel dieser Arbeit war es, die Muskel- und Sehnensteifigkeit bei Leistungssportlerinnen und Leistungssportlern unter Berücksichtigung anthropometrischer Parameter, sportartspezifischer Anforderungen sowie akuter und chronischer Belastungseinflüsse systematisch zu analysieren. Ein besonderer Fokus lag auf der Achillessehne, deren Steifigkeit in Abhängigkeit von Geschlecht, Alter, Körperzusammensetzung und Sportart untersucht wurde. Dabei zeigten sich signifikante geschlechtsspezifische Unterschiede sowie sportartspezifisch erhöhte Steifigkeitswerte, insbesondere bei sprintorientierten Disziplinen
Optimal Regularity of Area Maximizing Hypersurfaces in Minkowski Space
No full textIn 1982, Bartnik and Simon proved that area maximizing hypersurfaces are smooth, strictly spacelike and maximal (mean curvature zero) away from a singular set which consists of light rays connecting boundary points. Around the same time, Leon Simon conjectured that area maximizing hypersurfaces ought to be of class C^{1,1} across their singular set, and pointed out that, if correct, this regularity statement could not be improved to C^2 in view of a certain example. In this paper, we prove Leon Simon’s conjecture.1982 bewiesen Bartnik und Simon, dass flächenmaximierende Hyperflächen glatt, streng raumartig und maximal (mittlere Krümmung Null) sind, abgesehen von einer singulären Menge, die aus Lichtstrahlen besteht, die Randpunkte verbinden. Etwa zur gleichen Zeit stellte Leon Simon die Vermutung auf, dass flächenmaximierende Hyperflächen über ihre singuläre Menge hinweg der Klasse C^{1,1} angehören müssten, und wies darauf hin, dass diese Regularitätsaussage angesichts eines bestimmten Beispiels nicht auf C^2 verbessert werden könne, sollte sie zutreffen. In diesem Artikel beweisen wir Leon Simons Vermutung
Methodological approaches to researching the benefits and acceptance of digitalisation in healthcare
No full textDie Digitalisierung ist ein Transformationsprozess, der verschiedene Bereiche der
funktional differenzierten Gesellschaft betrifft und durch den vermehrten Einsatz von
vernetzter, elektrischer Technik gekennzeichnet ist. Für die Gesundheitsversorgung
werden die Potentiale der Digitalisierung vor allem in vernetzten Gesundheitsdaten
(elektronische Patientenakte), neuen Analysemöglichkeiten (z. B. Machine Learning) für
große Datenbanken (Big Data), sowie in der Ambulantisierung durch telemedizinische
und telepflegerische Versorgungsangebote gesehen. Für Patient:innen verspricht dieser
Wandel eine bessere Versorgung durch neue Therapieverfahren und erleichterte
Erreichbarkeit, sowie eine einfachere Navigation durch das Gesundheitssystem durch
Angebote wie Patientenportale oder die elektronische Patientenakte. Die vorliegende
Habilitationsschrift schlägt einen Methodenmix vor, um das Phänomen Digitalisierung in
der Gesundheitsversorgung wissenschaftlich zu fassen. Anhand der Methoden
Befragungen, Fokusgruppen und Interviews sowie systematische Literaturreviews lassen
sich Rückschlüsse auf die Versorgung für verschiedene Zielgruppen und für verschiedene
konkrete Technologien der Digitalisierung fassen. Diese Methoden können eingebettet
sein in verschiedene Forschungsdesigns wie dem cluster-randomisierten Experiment, der
Matched-Kontroll-Studie oder der zielgruppenspezifischen Online-Befragung. Dabei
bieten die verschiedenen Methoden eine Reihe von Vorteilen, aber auch Limitationen.
Ein Methodenmix, der die jeweiligen Stärken nutzbar macht und dabei die Limitationen
ausgleicht, wird als vielversprechendes Vorgehen in der Versorgungsforschung mit
Schwerpunkt Digitalisierung gesehen. Dabei sind jedoch zwei Reflexionen vorrangig: der
technologische Wandel und die forscherische Grundperspektive. Digitale
Gesundheitsleistungen sind in einem sehr dynamischen Marktsegment verortet, das
schnell neue Technologien erzeugt. Eine ausführliche und gründliche Evaluation ist in
diesem Umfeld oft schwierig möglich, da die neuen Technologien nach Abschluss der
Studie bereits technisch überholt sein könnten. Daher empfiehlt es sich, den Evaluationsoder
Forschungsansatz für Prototypen anzupassen. Außerdem sollte die
Grundperspektive nicht nur die unmittelbare Nutzung und Bewertung ins Auge fassen,
wie es oftmals geschieht, sondern gleichsam den Kontext und verschiedenen
Akteursperspektiven reflektieren. Hier ist vor allem das Theoriespektrum der
medizinischen Soziologie gefragt, das die existierenden und zukünftig entwickelten
(digitalen) Technologien in einen erklärenden Rahmen fassen und somit die Akteure im
Gesundheitssystem stärken kann
Identification and Long-Term Detection of Hepacivirus bovis Genotype 1 and 2 on a Cattle Farm in Germany
No full textIn 2020, a dairy farm in northwest Germany reported several cows with severe respiratory disease, fever, and reduced milk production. Multiple direct and indirect diagnostic methods were used to identify the cause of the disease. However, the pathogens detected could not be correlated with the severity of the clinical symptoms, so further diagnostic steps were taken. Blood and nasal swab samples were examined using next-generation sequencing (NGS) as part of a metagenomic analysis. For the first time in Germany, Hepacivirus bovis genotype 2 was detected. Real-time RT-PCR assays confirmed the presence of BovHepV genotypes 1 and 2 in the herd between 2020 and 2023. Analyses of complete and partial genome sequences demonstrated the presence of different virus variants in the herd over several years. In addition, the sequence data indicated that cattle can be reinfected with viruses belonging either to different BovHepV subtypes or to the same subtype. Although no direct link could be established between the detection of bovine hepaciviruses and the observed clinical symptoms, the PCR and sequence data obtained provide valuable insights into the epidemiology and pathogenesis of BovHepV infections
Further Evidence for the Immunosuppressive Activity of Transmembrane Envelope Protein p15E of Porcine Endogenous Retrovirus
No full textRetroviruses are immunosuppressive, and there is evidence that a highly conserved immunosuppressive domain (isu domain) in their transmembrane envelope protein contributes to this activity. Studies have shown that inactivated retroviruses, their purified transmembrane envelope proteins, and synthetic peptides corresponding to the isu domain inhibit mitogen-triggered proliferation of peripheral blood mononuclear cells (PBMCs) and modulate their cytokine and gene expression. This has been demonstrated for human immunodeficiency virus type 1 (HIV-1), as well as for beta- and gammaretroviruses and for both exogenous and endogenous retroviruses, including syncytins. In the case of HIV-1, homopolymers of its isu peptide stimulated an increased release of IL-10, IL-6, and other cytokines from human PBMCs. Up-regulated genes included IL-6, IL-8, and IL-10, as well as MMP-1, TREM-1, and IL-1β. In vivo, in a mouse tumor model, tumor cells that were unable to induce tumors in immunocompetent animals gained the ability to do so when expressing the transmembrane envelope protein or the isu domain of various retroviruses on their surface. Here, we demonstrate that the transmembrane envelope protein p15E of PERV can modulate cytokine expression in human PBMCs. Human 293 cells were transfected with four constructs that express a portion of p15E, including the isu domain, and were cultured in the presence of a selection medium containing hygromycin. The p15E-expressing cells were co-cultured with human PBMCs, leading to the release of IL-6 and IL-10 protein and the modulation of multiple cytokines and other markers, including IL-6, IL-10, IFN-α, TNF-α, MMP1, and SEPP1. Similar, but more pronounced, effects were observed when PERV-producing 293 and pig cells were used in parallel; both expressed higher levels of p15E. Additionally, p15E expression reduced MHC class I expression, and preliminary data indicate that p15E expression could have a protective effect against cellular cytotoxicity. This finding underscores the need for further research to elucidate the dynamics of p15E expression and its immunosuppressive activity. It also contributes to the understanding of the immunosuppressive properties of pathogenic retroviruses. Furthermore, expressing the immunosuppressive p15E of PERV on the surface of a pig xenotransplant may reduce the need for pharmaceutical immunosuppressants
A 30-year-old diesel tank: fungal-dominated biofilms cause local corrosion of galvanised steel
No full textThe increased use of biodiesel is expected to lead to more microbial corrosion, fouling and fuel degradation issues. In this context, we have analysed the metal, fuel and microbiology of a fouled diesel tank which had been in service for over 30 years. The fuel itself, a B7 biodiesel blend, was not degraded, and—although no free water phase was visible—contained a water content of ~60 ppm. The microbial community was dominated by the fungus Amorphotheca resinae, which formed thick, patchy biofilms on the tank bottom and walls. The tank sheets, composed of galvanised carbon steel, were locally corroded underneath the biofilms, up to a depth of a third of the sheet thickness. On the biofilm-free surfaces, Zn coatings could still be observed. Taken together, A. resinae was shown to thrive in these water-poor conditions, likely enhancing corrosion through the removal of the protective Zn coatings
Dataset for: Public Participation in China's State-Created ICT Spaces: Explaining Participation Patterns
No full textt has become commonplace for non-democratic regimes to integrate information and communication technologies (ICTs) into their governance system. However, how citizens make use of these new digital opportunities in an authoritarian setting remains understudied. Based on an online survey in China in 2021, we find that a surprisingly large share of Chinese citizens engages with the new ICT-based participatory venues. But ICTs seem to unfold their potential only for certain groups such as tech-savvy younger citizens with a higher income. Moreover, while citizens seem to be quite aware of the risks of using ICTs, such as data security breaches or digital surveillance, these do not seem to hamper participation. Rather, citizens trade off perceived risks for perceived benefits, such as higher levels of convenience, efficiency, or expected government responsiveness. Our study contributes to the literature on digital governance in authoritarian regimes, and the digital divide and technology acceptance literatures. Moreover, amid the tightening of political control in China, it offers insights into participatory developments under Xi Jinping
THz-Driven Coherent Phonon Fingerprints of Hidden Symmetry Breaking in 2D Layered Hybrid Perovskites
No full textMetal-halide perovskites (MHPs) emerged as a family of novel semiconductors with outstanding optoelectronic properties for applications in photovoltaics and light emission. Recently, they also attract interest as promising candidates for spintronics. In materials lacking inversion symmetry, spin-orbit coupling (SOC) leads to the Rashba-Dresselhaus effect, offering a pathway for spin current control. Therefore, inversion symmetry breaking in MHPs, which are characterized by strong SOC, has crucial implications. Yet, in complex low-dimensional hybrid organic-inorganic perovskites (HOIPs), the presence of and structural contributions to inversion symmetry breaking remain elusive. Here, employing intense THz fields, lattice dynamics carrying spectroscopic fingerprints of inversion symmetry breaking are coherently driven and observed in Ruddlesden-Popper (PEA)2(MA)n-1PbnI3n+1 perovskites, which are globally assigned to a centrosymmetric space group. We demonstrante coherent control by THz pulses over specific phonons, which are assigned to either purely inorganic or highly anharmonic hybridized cage-ligand vibrations. By developing a general polarization analysis for THz-driven phonons, linear and nonlinear driving mechanisms are pinpointed. From this, simultaneous IR- and Raman-activity of inorganic cage modes below 1.5 THz is identified, indicating mode-selective inversion symmetry breaking. By exploring the driving pathways of these coherent phonons, the groundwork is laid for simultaneous ultrafast control of optoelectronic and spintronic properties in 2D HOIPs
A case report of a pathology in the ‘whip’ of a flagellicaudatan sauropod
No full textFlagellicaudatan sauropods are well known for their elongated tails which end in a ‘whiplash’-like structure, consisting of biconvex rod-like caudal vertebrae lacking a neural arch. A remarkably well-preserved and relatively complete specimen of Barosaurus from the Upper Jurassic Morrison Formation preserves a number of these vertebrae, including the last two that terminate the axial series. The penultimate element preserves a distinct callus which we investigated, together with the terminal caudal vertebra, using X-ray computed tomography. A transverse fracture initiated the formation of the callus, highlighted by extensive, disorganized vascularization of the bone outside of the cortex. Healing was likely still ongoing as the vertebra remains in two parts. Although various etiologies can be proposed for the trauma, none can be unambiguously put forward as the cause. The last caudal shows an interesting vascular pattern, and together with the lack of a posterior articular surface, can here be definitely identified as the last vertebra in the axial series. There is substantial variability in the morphology of the last caudal vertebra throughout Sauropoda, and future studies should focus on the soft tissues in this part of the tail, thereby enlightening the potential function of the ‘whip’. We also highlight here the use of high-resolution scanning to reveal the internal structures of fossils in detail when consumptive analysis is not possible
Geschlechterunterschiede bei der posttraumatischen Belastungsstörung: aktuelle Evidenz zu Entstehung, Verlauf und Behandlung
No full textHintergrund
Geschlechterunterschiede bei psychischen Störungen sind weit verbreitet. Die posttraumatische Belastungsstörung (PTBS) zählt hierbei zu den Störungen mit den größten Prävalenzunterschieden zwischen Männern und Frauen.
Ziel der Arbeit und Methode
Dieser narrative Übersichtsartikel beleuchtet die aktuelle wissenschaftlichen Evidenz zu Geschlechterunterschieden in Entstehung, Diagnostik und Behandlung der PTBS.
Ergebnisse
Obwohl Männer häufiger traumatische Ereignisse erleben, haben Frauen ein zwei- bis dreifach höheres Risiko, an einer PTBS zu erkranken, und zeigen schwerwiegendere PTBS-Symptome als Männer. Die erhöhte Vulnerabilität von Frauen ist bisher nicht vollständig verstanden und auf eine Kombination aus biologischen und psychosozialen Faktoren zurückzuführen. Trotz ihres erhöhten Risikos sind Frauen sowie frauenspezifische Risikofaktoren in der relevanten Forschung unterrepräsentiert – es besteht ein Gender-Data-Gap. Männer erleben häufiger akzidentielle und bewaffnete Traumata, Frauen erleben häufiger sexuelle Gewalt. Während Frauen häufiger an komorbiden Angst- und affektiven Störungen leiden, tritt eine PTBS bei Männern vermehrt in Kombination mit Substanzmissbrauch auf. Männer mit einer PTBS nehmen seltener psychotherapeutische Hilfe in Anspruch als Frauen und profitieren weniger gut von evidenzbasierten traumafokussierten Interventionen.
Diskussion
Die differenzierte Betrachtung biologischer und psychosozialer Faktoren ist entscheidend, um Geschlechterunterschiede in der PTBS zu verstehen. Geschlechtersensible Ansätze in Diagnostik und Behandlung sowie die Berücksichtigung von Geschlecht über binäre Klassifikationen hinaus können helfen, Wissenslücken zu schließen und eine gezieltere Versorgung zu ermöglichen.Background
Sex and gender differences in mental disorders are widespread. Posttraumatic stress disorder (PTSD) is one of the mental disorders with the largest prevalence differences between women and men.
Aim of the paper and methods
This narrative review article highlights the current scientific evidence on sex and gender differences in the development, diagnostics and treatment of PTSD.
Results
Although men more frequently experience traumatic events women have a twofold to threefold higher risk of developing PTSD and experience more severe PTSD symptoms than men. The increased vulnerability of women is not yet fully understood and can be attributed to a combination of biological and psychosocial factors. Despite the higher risk, women and female-specific risk factors are underrepresented in relevant research, a gender data gap exists. Men are more likely to experience accidental and weapon-related trauma and women are more likely to be exposed to sexual violence. While women more frequently suffer from comorbid anxiety and affective disorders, PTSD in men occurs more frequently in combination with substance abuse. Men with PTSD are less likely to seek psychotherapeutic help than women and benefit less from evidence-based trauma-focused interventions.
Discussion
The differential consideration of biological and psychosocial factors is crucial to understanding sex and gender differences in PTSD. Sex and gender-sensitive approaches in diagnostics and treatment as well as the consideration of sex/gender beyond binary classifications can help to close knowledge gaps and enable more targeted care