Scientific publications of the Saarland University
Not a member yet
14321 research outputs found
Sort by
Response to Letter to the Editor from Sunaina and Mayilvaganan: Enhanced Recovery After Surgery (ERAS) Pathways for Aesthetic Breast Surgery: A Prospective Cohort Study on Patient-Reported Outcomes
Get PDFEvidence at play: evidence-based practices and barriers in biological maturation assessment among German football academies
Get PDFPurpose
This study examined the extent to which German male football academies adopt evidence-based practices (EBP) and their impact on the execution of biological maturation assessments. It also explored perceived barriers to implementing these assessments.
Methods
With a 71.4% completion rate, 40 support staff members from German male football academies completed an online survey. The survey included questions on clubs’ beliefs about EBP, maturation assessment and monitoring practices, and data utilization. Responses were structured as multiple-choice or unipolar Likert scale questions with four to five labeled points. A magnitude-based decision approach was used to interpret findings.
Results
Results indicate a strong integration of EBP within German football academies, reflected in an EBP index of 3.66 ± 0.89 on a 5-point Likert scale. Significant differences (p = 0.035) were observed between participants conducting biological maturation assessments (3.91 ± 0.65) and those who do not (3.44 ± 0.71). Time constraints (68%) and staffing limitations were identified as primary barriers.
Conclusion
The findings emphasize the positive adoption of evidence-based practices in German football academies, with higher EBP index scores linked to conducting biological maturation assessments. The higher EBP index scores among those conducting biological maturation assessments highlight the crucial role of organizational culture in implementation. Structural barriers, contributing to the perceived “time constraints”, are key challenges, while staff competence is not a limiting factor. Promoting innovative, solution-oriented practices could help address these barriers, enhance decision-making, and better align processes with long-term player development goals
Nutritional support in professional German football clubs and youth academies—a descriptive study
Get PDFProper nutrition is considered important for the maintenance of health and performance in football players. The more demanding the match and training schedule, the higher the requirements for nutritional advice are. Still, the amount and level of nutritional support is unknown in many (semi-)professional settings. Therefore, the goal of this study was to provide an overview of nutrition practices in clubs of the highest German football leagues and their youth academies. An online survey about nutritional support was distributed to 97 professional male (Bundesliga, 2nd Bundesliga, and 3rd division), female (Women’s Bundesliga), and academy club representatives of which 52 (54% response rate) replied. We found that ~83% (n = 43) of clubs provide some nutritional advice, mostly for the professional male (69%, n = 35) and academy teams (65%, n = 34), while only 32% (n = 12) of professional female teams receive support. Nutritional advice is primarily provided by either full-time coaches (27%) or external nutritionists (27%). In about 60% of elite German clubs, daily nutrition offers include one whole meal, sports foods and micronutrient supplementation. Clubs’ representatives (75%) concur that nutrition significantly impacts football performance. Challenges in the implementation of advice are seen in professional players being often quite resistant to advice and in the topic still being “very coach-dependent”. In conclusion, nutrition is regarded an important topic within surveyed clubs, but consistent support by nutrition professionals is sparse, especially for female players. To enhance the quality of nutritional support, professional clubs and academies might consider employing a full-time qualified nutritionist or dietitian
TRPV6 channel function is involved in endometrial epithelial cell Ca2+ signaling and female mouse fecundity
Get PDFThe Ca2+-selective transient receptor potential vanilloid 6 (TRPV6) channel plays a fundamental role in the female and male murine reproductive system. We have previously shown that TRPV6 is essential for male fertility, and necessary for a proper placental Ca2+ transport, embryonic bone development and calcification, as well as for extracellular matrix formation in the placental labyrinth. Here, we show that lack of functional TRPV6 results in impaired fecundity in female mice with increased latency to first pregnancy, longer interpregnancy intervals and fewer and smaller litters. In mouse endometrium the TRPV6 protein is expressed in epithelial cells (MEECs). Using patch clamp recording and Ca2+ imaging, we show TRPV6-dependent whole-cell currents and that TRPV6 contributes to cytoplasmic Ca2+ signaling in MEECs. MEECs lacking functional TRPV6 Ca2+ channels reveal a significantly reduced frequency of spontaneous cytosolic Ca2+ oscillations, shown in isolated cells and in situ in whole mount uterus preparations. Our results reveal a previously unknown physiological role for TRPV6 in the regulation of endometrial Ca2+ homeostasis and its impact on female fecundity in mice, providing a molecular and cellular framework for further investigation of reproductive disorders, such as those associated with defective Ca2+ regulation in women
Artificial Intelligence-based assessment for red blood cell-related disease characterization
Get PDFThe adaptability and deformability of red blood cells (RBCs) are crucial for efficient microvascular perfusion and gas exchange, enabling these cells to conform to varying vessel flow conditions. This thesis investigates changes in RBC deforma-bility occurring in diseases such as Neuroacanthocytosis Syndromes (NAS), Sickle Cell Disease (SCD), and conditions like COVID-19. Traditionally, diagnosing these conditions involves genetic analysis and manual assessment of RBC shapes. This thesis proposes an automated method using artificial intelligence (AI) and image processing to analyze single RBC shapes in real-time flow. This innovative approach shows promise in characterization diverse RBC shape abnormalities seen in blood disorders. Chapter one discusses blood properties and RBC behavior in microcapillaries. Chapter two explains details of materials and methods. The third chapter focuses on methodology development, including image processing tools and AI implemen-tation. In chapter four, RBC morphology is discussed in detail for diseases like COVID-19, NAS, SCD, and others. The thesis concludes by summarizing findings and suggesting future research directions.Die Deformierbarkeit von Erythrozyten (redbloodcells, RBCs) ist für eine effiziente mikrovaskuläre Durchblutung und den Gasaustausch von entscheidender Bedeutung, da sie es diesen Zellen ermöglicht, sich an unterschiedliche Strömungsbedingungen anzupassen. In dieser Arbeit werden Veränderungen in der Verformbarkeit der Erythrozyten untersucht, die bei Krankheiten wie Neuroakanthozytose-Syndromen (NAS), der Sichelzellkrankheit (SCD) und Erkrankungen wie COVID-19 auftreten. Für die Diagnose vieler Krankheiten sind traditionell eine genetische Analyse oder eine manuelle Bewertung der Erythrozytenform erforderlich. In dieser Arbeit wird eine automatisierte Methode vorgeschlagen, bei der KI und Bildverarbeitung eingesetzt werden, um die Form einzelner Erythrozyten in Echtzeit zu analysieren. Dieser innovative Ansatz ist vielversprechend für die Diagnose verschiedener Anomalien der Erythrozytenform, die bei Blutkrankheiten auftreten. Im ersten Kapitel werden die Eigenschaften von Blut und insbesondere das Verhalten der Erythrozyten in Mikrokapillaren beschrieben. Kapitel zwei erläutert Einzelheiten zu den verwendeten Materialien und Methoden. Das dritte Kapitel konzentriert sich auf die Entwicklung der Methodik, einschließlich der Bildverarbeitung und der KI-Implementierung. In Kapitel vier wird die Morphologie der Erythrozyten bei Krankheiten wie COVID-19, NAS, SCD und anderen Krankheiten im Detail diskutiert. Die Arbeit schließt mit einer Zusammenfassung der Ergebnisse und Vorschlägen für zukünftige Forschungsrichtungen ab
Multivariate Analyse von Einflussgrößen auf den Entlasszeitpunkt von n = 8.026 Patienten in einem ländlichen norddeutschen Krankenhaus
Get PDFMultivariate Analyse der Entlasszeitpunkte in einem ländlichen Krankenhaus der Grund- und Regelversorgung in Norddeutschland
Bettenkapazitäten, steigender wirtschaftlicher Druck und der demografische Wandel führen zu Kapazitätsproblemen in der deutschen Krankenhauslandschaft. Hierbei kristallisiert sich der Entlassungsprozess immer mehr als Nadelöhr des Belegungsmanagementes heraus. Der Einfluss wurde gemessen als Entlasszeitpunkt am Entlasstag. Diese Analyse konnte eine Vielzahl patientenspezifischer aber auch organisationsspezifischer Faktoren erfassen, die sich in ihrer jeweiligen Einflussstärke jedoch erheblich unterscheiden. So konnte die behandelnde Fachabteilung als stärkster Regressor erkannt werden, während die Komplexität einer Erkrankung/Verletzung, gemessen als Patient Clinical Complexity Level, einen untergeordneten Einfluss aufweist, während Patienten mit einer Demenz einen früheren Entlasszeitpunkt aufweisen. Der Entlassungsprozess kann durch gezielte organisatorische Weisungen und eine Einführung eines strukturierten Entlassungsmanagementes der jeweiligen Fachabteilung maßgeblich beeinflusst werden und so das Belegungsmanagement effizienter gestalten.
Diese Arbeit beschäftigt sich damit, anhand einer multivariaten linearen Regressionsanalyse mögliche Faktoren im Entlassungsprozess zu erfassen und diese gleichzeitig zu quantifizieren.Multivariate analysis of discharges in a teaching hospital in Lower Saxony
Bed capacities, increasing economic pressure and demographic change are leading to capacity problems in the German hospital landscape. In this context, the discharge process is increasingly emerging as the bottleneck of occupancy management. With the help of a multivariate linear regression analysis, this study attempts to capture possible factors of the discharge process and to quantify them at the same time. The influence was measured as discharge time on discharge day. Our analysis was able to capture a large number of patient-specific but also organisation-specific factors, which, however, differ largely in their respective influence. Thus, the treating department could be identified as the strongest regressor, while the complexity of an illness/injury, measured as Patient Clinical Complexity Level, has a subordinate influence. Interestingly patients with dementia have a better discharge before noon rate. The discharge process can be significantly influenced by targeted organisational instructions from the respective department and thus make occupancy management more efficient in order to avoid bottlenecks
Modellgestützte Entwicklung dielektrischer Elastomer-Aktoren: Simulation, Aufbau und Validierung intelligenter Antriebslösungen
Get PDFDiese Dissertationsschrift untersucht zwei unterschiedliche Ansätze zur Weiterentwicklung dielektrischer Elastomer-Aktoren (DE-Aktoren) mit dem Ziel, deren Einsatz in realen Anwendungen zu ermöglichen. Im ersten Ansatz wird ein neuartiges Softrobotik-System vorgestellt, das auf einer bistabilen Mechanik basiert und mehrdimensionale, steuerbare Bewegungen erlaubt. Die entwickelte Struktur wurde modellbasiert ausgelegt und experimentell validiert. Der zweite Schwerpunkt liegt auf der Entwicklung einer energieeffizienten, dynamisch angetriebenen Pumpe auf DE-Basis. Der hierfür konzipierte Prototyp erreicht Leistungswerte, die mit konventionellen Technologien vergleichbar sind, und integriert erstmals eine kompakte Elektronik mit Self-Sensing-Funktion zur autonomen Anpassung der Ansteuerfrequenz an den aktuellen Lastdruck. Die Ergebnisse zeigen, dass beide Konzepte wesentliche Fortschritte von der Grundlagenforschung bis hin zu anwendungsnahen Demonstratoren darstellen. Sie legen damit den Grundstein für die zukünftige Integration von DE-Aktoren in funktionale Softrobotik- und Fluidsysteme, die herkömmliche Antriebstechnologien ergänzen oder ersetzen können.This work presents two distinct approaches for advancing dielectric elastomer actuators (DEAs) toward real-world applications. The first focuses on a novel soft robotic system based on a bistable actuator design that enables multidimensional, controllable motion. The structure was developed using a model-based design process and experimentally validated. The second approach centers on the development of an energy-efficient, dynamically driven DEA-based pump. The prototype achieves performance levels comparable to conventional technologies and includes, for the first time, a compact electronics unit featuring self-sensing functionality. This enables autonomous adjustment of the driving frequency in response to the current load pressure. The results demonstrate that both systems represent significant progress, ranging from innovative concepts in fundamental research to application-oriented demonstrators. These developments lay the foundation for the future integration of DEAs into soft robotic and fluidic systems, offering the potential to complement or replace conventional actuation technologies
Kontsevich-Zorich monodromy of Origamis from the aspect of Arithmeticity
Get PDFA translation surface is a compact Riemann surface obtained as a collection of finitely many polygons in the plane with glued parallel edges of the same length by translations. There is a natural action of the group of invertible real 2x2-matrices with positive determinant on the moduli space of translation surfaces by applying matrices to the polygons and regluing them by the same combinatorial relation. Under rare circumstances an orbit of this action is closed in the moduli space of translation surfaces. One class of translation surfaces where this happens are origamis, which consist of finitely many unit squares. The orbit of an origami parametrizes a family of compact Riemann surfaces. We consider the family of first singular cohomology groups with complex coefficients defined by this family of compact Riemann surfaces. It can be given the structure of a flat holomorphic vector bundle. For certain classes of origamis we will study the monodromy group of this vector bundle from the aspect of arithmeticity.Eine Translationsfläche ist eine kompakte Riemannsche Fläche, die man dadurch erhält, dass man endlich viele Polygone in der Ebene an parallelen Kanten gleicher Länge durch Translationen verklebt. Es gibt eine natürliche Operation der Gruppe der invertierbaren reellen 2x2-Matrizen mit positiver Determinante auf dem Modulraum der Translationsflächen, indem wir die Matrizen auf die Polygone anwenden und dann erneut nach den gleichen kombinatorischen Relationen verkleben. In seltenen Fällen ist eine Bahn dieser Aktion abgeschlossen im Modulraum der Translationsflächen. Eine Klasse von Translationsflächen, für die dies eintritt, sind Origamis. Diese bestehen aus endlich vielen verklebten Einheitsquadraten. Die Bahn eines Origamis parametrisiert eine Familie kompakter Riemannscher Flächen. Wir betrachten die Familie der ersten singulären Kohomologien mit komplexen Koeffizienten, die durch diese Familie kompakter Riemannscher Flächen definiert wird. Ihr kann die Struktur eines flachen holomorphen Vektorbündels gegeben werden. Wir werden für bestimmte Klassen von Origamis die Monodromiegruppe dieses Vektorbündels unter dem Gesichtspunkt der Arithmetizität studieren.Deutsche Forschungsgemeinschaft (DFG): SFB-TRR 195 Symbolic Tools in Mathematics and their Application
Hepatic Inflammation and Liver Injury in a Model of Bacterial Infection Triggered Acute-on-Chronic Liver Injury
Get PDFBackground and Aim
Acute-on-chronic liver failure (ACLF) is characterized by acute decompensation of chronic liver disease in the presence of an acute trigger, and bacterial infection (BI) is the most common trigger of ACLF. Therefore, we aimed to establish a mouse model that mimics bacterial infection-related acute-on-chronic liver failure (BI-ACLF) to study the ongoing pathophysiological processes during disease progression.
Methods
Wild-type C57BL/6J (n = 12; wild-type, WT) and Abcb4−/− (n = 12; knockout, KO) with underlying chronic fibrosing liver disease were intraperitoneally injected either with 0.9% NaCl or 4-mg/kg lipopolysaccharide (LPS) to establish four experimental groups, namely, a control group (WT-NaCl), an acute injury group (WT-LPS), a chronic liver disease group (KO-NaCl), and an acute-on-chronic group (KO-LPS). Hepatic expressions (relative to Gapdh) of Il-6, Crp, Tnf-α, Rantes, Tlr4, Mcp1, Il-10, Il-2, Il-22, Il-17a, and Tgf-β were quantified by the 2−ΔΔCt method. Liver injury and inflammation were evaluated by Sirius red and H&E stainings, respectively. Immunohistochemical stainings were used to assess apoptosis (Ck-18 and H2Ax), necrosis (Cas-1 and Hmgb-1), and macrophage polarization (M1 markers CD64 and CD86; M2 markers CD206 and Arg1). M1 markers (CD64 and CCR7) and M2 markers (CD163 and Arg1) were further analyzed by western blot analysis.
Results
Hepatic cytokines and chemokines, monocyte chemoattractant protein-1 (Mcp-1), interleukins Il-2, Il-22, and regulated on activation, normal T-cell expressed and secreted (Rantes) were significantly upregulated in mice of KO-LPS groups compared to their counterparts. Induction of pyroptosis, apoptosis, and macrophage polarization towards the M1 phenotype was evident.
Conclusion
Differential expression of hepatic cytokines and chemokines in Abcb4−/− mice upon LPS challenge provides insight into potential mediators of disease progression in this dual-hit model of BI-ACLI. Our findings suggest that increased expression of IL-6, IL-2, IL-22, and RANTES may be associated with inflammatory responses that contribute to disease exacerbation in this refined model