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Auswirkungen einer zwölfmonatigen, telefonbasierten Lebensstilintervention auf die objektive körperliche Aktivität, die Ernährungsqualität und das HbA1c bei Typ-2- Diabetiker*innen
No full textHintergrund: Diabetes zählt zu den weltweit häufigsten chronischen Krankheiten. 90% der Betroffenen leiden an Typ-2-Diabetes mellitus. Damit gehen oftmals makro- und mikrovaskuläre Komplikationen, diverse Komorbiditäten, eine eingeschränkte Lebensqualität und grosse wirtschaftliche Kosten einher. Obschon Patient*innen zu vermehrter körperlicher Aktivität und einer gesünderen Ernährung angehalten werden, setzen sie diese Empfehlungen nur unzureichend um. Das kann zu Hyperglykämie, Langzeitkomplikationen, Morbidität sowie vorzeitiger Mortalität führen.
Methoden: 100 Studienteilnehmende wurden in die Interventionsgruppe (IG, n = 51) mit persönlichem Gesundheitscoaching und die Kontrollgruppe (KG, n = 49), unter Beibehaltung der Standardtherapie, randomisiert. Zu drei Messzeitpunkten wurden Daten zur objektiven körperlichen Aktivität (sedentäres Verhalten, leichte sowie moderat bis intensive körperliche Aktivität [MVPA] und Schritte) mittels Beschleunigungsmesser, zur Ernährungsqualität (mHEI-2015) mittels 7-Tages-Ernährungsprotokolle und zum HbA1c erhoben und hinsichtlich Gruppendifferenzen nach sechs und zwölf Monaten analysiert.
Ergebnisse: Zu keinem Parameter wurden statistisch signifikante Gruppendifferenzen gefunden, mit Ausnahme der MVPA-Zeit nach zwölf Monaten. Dort hatte die IG im Vergleich zur KG eine mittlere MVPA-Zeit von zusätzlichen 10.82 min/Tag (95%-CI: 0.53-21.10; p = 0.0396).
Schlussfolgerungen: Die Arbeit ist bezüglich der Wirksamkeit einer zwölfmonatigen, telefonbasierten Lebensstilintervention auf die Veränderungen der objektiven körperlichen Aktivität, der Ernährungsqualität und des HbA1c-Spiegels nach Interventionsende im Vergleich zur Standardtherapie mit zusätzlicher einmaliger schriftlicher Ernährungs- und Bewegungsempfehlung und Zugang zu einer App nicht aussagekräftig. Einzig in Bezug auf die mittlere MVPA-Zeit konnte die Wirksamkeit der Lebensstilintervention nach zwölf Monaten aufgezeigt werden
Zusammenhang zwischen körperlicher Aktivität und physischen und kognitiven Leistungsindikatoren bei präpubertären Kindern
No full textHintergrund: Die vorliegende Masterarbeit widmet sich der Untersuchung des Zusammenhangs zwischen körperlicher Aktivität, motorischer Leistungsfähigkeit und schulischen Leistungen im Kindesalter. Vor dem Hintergrund des zunehmenden Bewegungsmangels bei Kindern und Jugendlichen in den letzten Jahrzehnten wird die Bedeutung von Bewegung für die motorische und kognitive Entwicklung hervorgehoben. Der aktuelle Forschungsstand zeigt sich jedoch uneinheitlich, was die konkreten Effekte körperlicher Aktivität auf schulische Leistungen betrifft. Methoden: Um diese Forschungslücke zu adressieren, wurde eine Querschnittsstudie mit 21 Grundschulkindern im Alter von 7-11 Jahren durchgeführt. Mittels Kraftmessplatte, Akzelerometrie, Körperzusammensetzungsanalyse, Isomed 2000 (Kraftmessung Kniestrecker), Griffkraftmessgerät und Fragebögen wurden verschiedene Parameter der motorischen Leistungsfähigkeit, des Aktivitätsverhaltens und der schulischen Leistung (Noten in Deutsch, Mathematik, Sport) erfasst. Die Datenanalyse erfolgte primär über Korrelations- und Regressionsanalysen. Resultate und Schlussfolgerung: Die Ergebnisse zeigten keine statistisch signifikanten Zusammenhänge zwischen den erfassten Facetten der körperlichen Aktivität und den Schulnoten. Auch in den multiplen Regressionsanalysen erwiesen sich die Bewegungs- und Fitnessparameter nicht als bedeutsame Prädiktoren der Schulleistung. Die motorischen Testergebnisse und akzelerometrischen Kennwerte variierten interindividuell erheblich. Trotz methodischer Limitationen wie der geringen Stichprobengrösse und des querschnittlichen Designs liefert die Studie interessante Hinweise für zukünftige Forschungsbemühungen. Es bedarf weiterer Untersuchungen mit längsschnittlichem Design, grösseren Stichproben und unter Berücksichtigung möglicher Moderatorvariablen, um die komplexen Zusammenhänge zwischen körperlicher Aktivität und schulischen Leistungen besser zu verstehen. Für die Praxis implizieren die Befunde, dass Bewegungsförderung und kognitive Anforderungen vereinbar sind und sich nicht zwangsläufig konkurrieren
Abschnittsanalyse der Ski Alpin Weltcup Abfahrt Strecken der Frauen in der Saison 2023 / 2024
No full textTheoretischer Hintergrund: Neben den beeinflussbaren Faktoren, wie die physischen Voraussetzungen der Athlet:innen, bestimmen sowohl das Gelände als auch die Kurssetzung die Geschwindigkeit der Athlet:innen (Gilgien et al., 2015). Exogene Einflüsse, wie Wetter- und Schneeverhältnisse sowie das Material, sind weitere Einflussfaktoren auf die Leistung der Athlet:innen (Bruhin et al., 2018; Elfmark et al., 2021; Gilgien et al., 2021).
Methoden: Diese Längsschnittstudie analysierte alle weiblichen Athletinnen, die in der Saison 2023/24 in einem offiziellen Weltcup- Training oder Rennen in die Top 30 fuhren. Die Rennstrecken wurden basierend auf den offiziellen Daten des internationalen Skiverbands in Abschnitte unterteilt. Eine Abschnittskategorisierung erfolgte anhand der Zeit, die die Tagesschnellste im Abschnitt in der Hocke- Position war. Zur Identifizierung von Schlüsselabschnitten wurde eine Pearson Korrelation mit ergänzendem Signifikanztest durchgeführt.
Ergebnisse: Über die gesamte Saison zeigte keine Abschnittsklassifizierung eine signifikant höhere Korrelation als die anderen (Gleiten (Flach) r = 0.48; Mix (Coupiert) r = 0.60; Technisch (Steil) r = 0.57). Die rennortspezifischen Analysen offenbarten jedoch, dass einzelne Abschnitte eine stärkere Korrelation in Bezug auf die Schlussrangierung aufwiesen als andere.
Schlussfolgerung: Eine abschliessende Aussage über Schlüsselabschnitte lässt sich anhand dieser Untersuchungen nicht treffen. In Rennorten, wie bspw. Val d`Isere konnten Schlüsselabschnitte identifiziert werden, während dies, bspw. in St. Moritz, aufgrund variabler exogener Faktoren nicht möglich war. Die Abschnittsklassifizierung Mix (Coupiert) war absolut gesehen am häufigsten rennentscheidend, wobei der durchschnittliche Pearson- Korrelationskoeffizient nur wenig von den anderen Abschnitten abwich. Diese Ergebnisse unterstreichen die Bedeutung einer präzisen Analyse der Abschnitte und exogener Faktoren zur Verbesserung der Trainings- und Rennstrategien
Flavor physics at high-energy colliders
Get PDFFlavor physics is a key aspect of the Standard Model (SM) of particle physics, allowing us to study fundamental interactions and search for deviations from the SM. In three parts, this thesis explores flavor dynamics at high-energy colliders and the complementarity with low-energy flavor observables, aiming both to build on the successes of the SM and to identify areas where it falls short.
The first part of the thesis revisits the landscape of short-distance new physics by analysing rare decays of hadrons and high-energy Drell-Yan processes. One of the main contributions of this work is the implementation of the SM Effective Field Theory (SMEFT) predictions and experimental data of the high-mass Drell-Yan tails within the {\tt flavio} framework. This implementation is then used together with recent experimental data from transitions, to explore the potential for new physics beyond the SM in these rare decays. Our analysis explores the parameter space of the SMEFT as well as several explicit models, such as and leptoquark scenarios, to assess their compatibility with the experimental data.
In the second part, we explore exclusive charged current semileptonic decays of hadrons with underlying transitions as a window into new physics. By leveraging the SMEFT framework again, we show that the new physics contributions to these decays are closely correlated with effects in rare neutral current decays, neutral meson mixing and high-mass Drell-Yan tails. Considering all the available experimental data, we find that the parameter space relevant for decays is already highly constrained, leaving little room for new physics. We also identify tree-level mediators that could contribute to the transitions, show how they are mostly constrained by the complementary observables, and construct an explicit model where decays put relevant bounds on the parameter space.
Finally, the last part takes motivation from the hints of new physics in rare flavor-changing neutral current transitions , and explores the discovery prospects of possible new physics at future high-energy colliders, in particular the FCC-hh and a multi-TeV muon collider. A model-independent analysis concerning semileptonic SMEFT operators as well as construction of explicit models featuring bosons and leptoquarks is carried out to assess the potential for discovery at these colliders. For the scenarios at hand, we find similar prospects for FCC-hh and 3 TeV muon collider to be effective in probing the parameter space of SMEFT and models while a 10 TeV (or higher) muon collider is required to fully probe the parameter space of leptoquark models
In vivo functional validation of transcriptional regulators involved in vertebrate skeletal cell fate convergence
No full textThe vertebrate skeleton was a major evolutionary innovation that appeared sequentially in different parts of the body. Developmentally, cells forming this endoskeleton originate from three different embryonic lineages. The ectoderm-derived cranial neural crest gives rise to the craniofacial skeleton while the mesoderm-derived somite and lateral plate give rise to the axial and appendicular skeleton, respectively. Despite these distinct developmental origins, the three lineages differentiate into skeletal cell populations displaying not only functional but also transcriptional similarities. However, the exact molecular mechanisms underlying the convergent specification and differentiation of these tissues remain unclear.
This PhD thesis aims at identifying origin-specific regulators involved in this process of skeletogenic cell fate convergence, as well as investigating their regulatory interactions, to provide insights into the underlying gene regulatory networks in each skeletal lineage.
To do so, single-cell transcriptional and chromatin-profiling analyses were conducted on chicken-derived, differentiating skeletal progenitors from each embryonic lineage, revealing a set of shared and embryonic-specific transcription factors (TFs) with a potential role in skeletal cell fate specification. Additionally, predicted cis-regulatory elements were identified and validated for their activity and origin-specificity.
Furthermore, we developed and tested an optimized in vivo clustered regularly interspaced short palindromic repeats (CRISPR) screening procedure with single-cell transcriptomic readouts, to functionally validate TFs in developing chicken forelimbs, specifically targeting the tissue giving rise to skeletal progenitors. To do so, we adapted CRISPR constructs to enable the detection of guides during single-cell RNA sequencing while still maintaining CRISPR perturbation efficiencies. We conducted bioinformatic analyses on CRISPR perturbed cells and identified potential perturbation hits for a series of TFs with effects in genes related to cell proliferation, transcriptional regulation and skeletal development.
Collectively, this present work contributes to our understanding of the gene regulatory mechanisms underlying the convergent skeletal cell fate specification from three distinct precursor lineages during vertebrate embryogenesis
Understanding the metabolic signal in hydrogen isotope values of plant organic compounds
Get PDFThe stable isotope composition of archived plant material such as leaf wax derived n-alkanes and tree ring derived cellulose, have proved to be exciting new tools for understanding plant physiology and metabolism. Since the processes that shape plant organic compound stable isotope compositions (δ) of carbon (C; δ13C), nitrogen (N; δ15N), and oxygen (O; δ18O) are relatively well understood, these are frequently used as proxies for specific plant physiological processes. By contrast, the stable isotope composition of hydrogen (H; δ2H) from organic compounds is rarely used. All H atoms in plant organic compounds ultimately originate from water, and therefore, climate driven δ2H values of source and leaf water have a strong impact on δ2H values in plant organic compounds. As such, it has been postulated that δ2H values of archived plant organic compounds could be used to reconstruct past climate. However, it has been shown that biochemical 2H-fractionation further shapes organic compound δ2H values. The variable biochemical 2H-fractionation that occurs during organic compound biosynthesis has been linked to plant C-metabolism. Although this complicates the interpretation of the climate signal in organic plant compound δ2H values, it indicates that H isotopes may also be a valuable tool to extract plant metabolic information. The exact processes that drive biochemical 2H-fractionation are still poorly understood, and therefore, interpretation of the metabolic signal in organic compound δ2H values is not yet precise enough to make accurate predictions. In this dissertation, different studies are presented with the aim of providing new insight into the processes that shape biochemical 2H-fractionation during plant organic compound biosynthesis. The results of this work show that within-species, biochemical 2H-fractionation during acetogenic lipid (fatty acid and n-alkane) biosynthesis is less sensitive to changes in C-metabolism compared to during synthesis of cellulose and the isoprenoid lipid compound, phytol. Despite this, among species grown in the same location, acetogenic lipid δ2H values strongly varied, much beyond that in leaf water δ2H values. This suggests that there is a highly variable biochemical 2H-fractionation mechanism during acetogenic lipid synthesis which was shown to be strongly related to eudicot phylogeny. Notably, δ2H values of chloroplast produced fatty acids were typically not correlated to those of phytol, suggesting that the origin of biochemical 2H-fractionanation occurs within the specific biosynthetic pathways. Lastly, this work led to the hypothesis that phytol δ2H values are likely influenced by the 2H-enriching effect of photorespiration, which, based on precursor molecule H atoms incorporated, also affects cellulose δ2H values but not those of acetogenic lipids. Overall, the results presented here constrain the possible biochemical 2H-fractionation processes that shape organic compound δ2H values and offer new hypotheses that can be tested to further improve the understanding of biochemical 2H-fractionation during organic compound biosynthesis
Does Early Regional Scientific Leadership Translate Into Lasting Innovation Advantage?
Get PDFWe examine whether ’pioneer’ regions - early leaders in generating new ideas in emerging scientific fields - develop and maintain an innovation advantage in the same fields over time. Our analysis covers 24 disruptive technologies (e.g. AI, cloud computing) in thousands of OECD regions over 20 years. The results show that pioneer regions gain a significant and growing innovation advantage over non-pioneer regions. This advantage is most pronounced in "super-cluster" regions, which are leaders in both science and related innovation. These findings highlight the importance of early scientific leadership for sustained regional innovation and suggest important policy implications
A New Framework for Error Analysis in Computational Paleographic Dating of Greek Papyri
No full textThe study of Greek papyri from ancient Egypt is fundamental for understanding Graeco-Roman Antiquity, offering insights into various aspects of ancient culture and textual production. Palaeography, traditionally used for dating these manuscripts, relies on identifying chronologically relevant features in handwriting styles yet lacks a unified methodology, resulting in subjective interpretations and inconsistencies among experts. Recent advances in digital palaeography, which leverage artificial intelligence (AI) algorithms, have introduced new avenues for dating ancient documents. This paper presents a comparative analysis between an AI-based computational dating model and human expert palaeographers, using a novel dataset named Hell-Date comprising securely fine-grained dated Greek papyri from the Hellenistic period. The methodology involves training a convolutional neural network on visual inputs from Hell-Date to predict precise dates of papyri. In addition, experts provide palaeographic dating for comparison. To compare, we developed a new framework for error analysis that reflects the inherent imprecision of the palaeographic dating method. The results indicate that the computational model achieves performance comparable to that of human experts. These elements will help assess on a more solid basis future developments of computational algorithms to date Greek papyri
Advanced polymer compartments: from catalytic nanocompartments to organelle mimics for biomedical applications
Get PDFPolymersomes, vesicles enclosing an aqueous cavity and self-assembled by block copolymers are a powerful platform for creating various nano- and micro-devices, finding applications in therapeutic delivery and diagnostic systems, local and on-demand consumption or production of molecules by encapsulated enzymes and mimics of natural compartments. Highlighting the versatility of the block copolymers, this work presents how we can combine amphiphilic block copolymers with molecules and biomolecules to create advanced polymer nanocompartments for: 1. controlled drug delivery, 2. local inversion of a drug metabolite to its active form, 3. simultaneous generation of therapeutically relevant compounds for promoting drug synergism and 4. emulating naturally-occurring organelles in a bottom-up, photoreceptor mimic.
First, we engineered polymersomes for delivering drugs in a highly spatiotemporally controlled manner. A hydrophobic synthetic molecular rotary motor, activated by irradiation with low-power visible light
Atomistic simulations of molecule formation and decomposition: from astrophysics to atmospheric chemistry
Get PDFAtomistic simulations, with their increasing accuracy and predictive capabilities, have become indispensable tools for understanding molecular behavior at the atomic level. Employing reactive molecular dynamic (MD) simulations with accurate interaction potentials offers valuable insights into both atmospheric and interstellar chemistry. This thesis explores the reaction dynamics of small molecules in gas and condensed phases under controlled conditions.
In the gas phase, photoinduced dynamics of syn-acetaldehyde oxide Criegee intermediate leading to the formation of vinoxy and hydroxyl (OH) radicals, as well as glycolaldehyde is explored. Molecular dynamics simulations are performed, utilizing classical force fields and neural network based potential energy surfaces at the MP2 and CASPT2 levels of theory. By comparing the computed final OH translational
and rotational state distributions with experimental data, the O–O bond dissociation energy