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The 28th insolvency law: Reflections on a lex concursus europaea
No full textMore than ever before the global situation and Europe's position in it let it appear advisable to speed up harmonsation processes. The present authors present a plea for a EU Regulation which offers a complete insolvency law as an option that can be chosen by certain European companies from a certain size on. Thereby creating a harmonised insolvency law at least for certain actors on the European market. The delays usually inherent in the previous harmonisation efforts from Brussels would, thus, be surpassed in the most rapid way.Peer Reviewe
Bialgebraic geometry and fundamental groups of quasi-projective varieties
No full textDiese Dissertation präsentiert neue Ergebnisse bezüglich Kollár-Pardon und seiner Verallgemeinerungen sowie Fundamentalgruppen glatter komplexer quasi-projektiver Varietäten. Wir beweisen ein Analogon der Kollár-Pardon-Vermutung für kompakte Riemannsche Mannigfaltigkeiten. Wir zeigen nämlich, dass wenn die universelle Überlagerung einer kompakten Riemannschen Mannigfaltigkeit eine definierbare Riemannsche Mannigfaltigkeit in einer o-minimalen Struktur ist, sie eine definierbare Faserung über einer kompakten einfach zusammenhängenden Basis mit glatten Fasern zulässt, die lokal symmetrisch sind. Sie ist außerdem Riemann-homogen, falls zusammenziehbar. Wir leiten die Kollár-Pardon-Vermutung für glatte komplexe projektive Varietäten ab, die eine bidefinierbare Kähler-Metrik zulassen. Wir untersuchen die Fundamentalgruppen komplexer normaler quasi-projektiver Varietäten, deren universelle Überlagerung biholomorph zur Analytifizierung einer algebraischen Varietät ist. Wir zeigen, dass jede lineare Darstellung einer solchen Gruppe über einem Körper ein virtuell nilpotentes Bild hat. Ihr Bild ist außerdem virtuell abelsch, falls die Albanese-Abbildung eigentlich ist. Wir untersuchen die BNS-Mengen der Fundamentalgruppen glatter komplexer quasi-projektiver Varietäten. Wir verallgemeinern Delzants Theorem über BNS-Klassen von Kähler-Gruppen auf den Fall von Fundamentalgruppen glatter quasi-projektiver Varietäten. Damit zeigen wir, dass wenn eine solche Gruppe virtuell auflösbar ist, sie virtuell nilpotent ist. Wir geben Anwendungen dieser Ergebnisse auf die Topologie von h-speziellen und Campana-speziellen quasi-projektiven Varietäten und Succius tropische Schranke für Hyperebenenarrangements.This thesis presents new results concerning Kollár-Pardon and its generalisations, and fundamental groups of smooth complex quasi-projective varieties. We prove an analogue of the Kollár-Pardon Conjecture for compact Riemannian manifolds. Namely, we show that if the universal cover of a compact Riemannian manifold is a definable Riemannian manifold in some o-minimal structure, it admits a definable fibration over a compact simply connected base with smooth fibres being locally symmetric. It is moreover Riemann homogeneous if contractible. We deduce the Kollár-Pardon conjecture for smooth complex projective varieties admitting a bidefinable Kähler metric. We study the fundamental groups of complex normal quasi-projective varieties whose universal cover is biholomorphic to the analytification of an algebraic variety. We show that , every linear representation of such group over a field has a virtually nilpotent image. Its image is moreover virtually abelian if the Albanese map is proper. We study the BNS sets of the fundamental groups of smooth complex quasi-projective varieties. We generalise Delzant's theorem on BNS classes of K\"ahler groups to the case of fundamental groups of smooth quasi-projective varieties. Using this, we show that if such a group is virtually solvable, it is virtually nilpotent. We give applications of these result to topology of h-special and Campana-special quasi-projective varieties and Suciu's tropical bound for hyperplane arrangements
Topological recursion for generalised Kontsevich graphs and r-spin intersection numbers
No full textIn 1992, Kontsevich introduced certain ribbon graphs [ 47 ] as cell decompositions for combinatorial models of moduli spaces of complex curves with boundaries in his proof of Witten’s conjecture [ 59 ]. In this work, we define four types of generalised Kontsevich graphs and find combinatorial relations among them. We call the main type ciliated maps and use the auxiliary ones to show they satisfy a Tutte recursion that we turn into a combinatorial interpretation of the loop equations of topological recursion for a large class of spectral curves. It follows that ciliated maps, which are Feynman graphs for the Generalised Kontsevich matrix Model (GKM), are computed by topological recursion. The GKM relates to the r -KdV integrable hierarchy and since the string solution of the latter encodes intersection numbers with Witten’s r -spin class, we find an expression for the generating series of ciliated maps in terms of r -spin intersection numbers, implying that they are also governed by topological recursion. In turn, this paves the way towards a combinatorial understanding of Witten’s class. This new topological recursion perspective on the GKM also provides concrete tools to explore the conjectural symplectic invariance property of topological recursion for large classes of spectral curves.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.Universitat Politècnica de CatalunyaPeer Reviewe
Gender differences in self-reported hearing loss and hearing aid use: a cross-national comparison
No full textBackground: Objective measurements estimated that 1.57 billion people globally had hearing loss in 2019. However, where audiologists are sparse, self-reported measures have been suggested as alternatives to assess burden. Moreover, research suggests this number varies by gender, due to biological and social mechanisms. Further refining our knowledge of the global prevalence of hearing loss will provide better understanding of which groups are most affected and how to best allocate resources. Methods: Using Gateway to Global Ageing data and the South African National Income Dynamics Study, we estimated the prevalence and men:women ratio of self-reported hearing loss and hearing aid use for 28 countries. Hearing loss was measured as having fair/poor hearing or reporting hearing aid use. We included 664 580 observations of individuals aged 50+ years. Results: We found that the four countries with the highest levels of hearing loss (China 65%, South Korea 39%, Mexico 33%, Brazil 31%) also had the lowest reported hearing aid use (as low as 1% in China). Though men were more likely than women to report hearing loss in nearly all countries, especially in regions with higher hearing aid use (USA, Northern/Western Europe), China, South Korea and South Africa reported no gender difference. As the prevalence of hearing loss and hearing aid use increased with age, gender differences generally decreased. Conclusion: International variation underscores the importance of country context in shaping perceived hearing and hearing aid use. Regions with high levels of hearing loss and low hearing aid use may be especially amenable to interventions.http://dx.doi.org/10.13039/100000049National Institute on AgingSt Andrews-Max Planck PhD Studentship in Population Healthhttp://dx.doi.org/10.13039/501100006188Einstein Stiftung BerlinPeer Reviewe
An NDR1/HIN1-like gene identified in Fraxinus excelsior L. may trigger defence mechanisms in response to virus infection
No full textThe defence-associated NDR1/HIN1-like (NHL) gene plays an important role in triggering plant defences in response to biotic stresses. The NHL gene is involved in gene-for-gene-mediated resistance mechanisms in response to attack by bacterial, fungal, and viral pathogens. Our study investigated the variation in 72 virus defence gene candidates annotated in the F. excelsior genome. Among all single nucleotide polymorphisms (SNPs) and indels detected in these candidates, one polymorphic site in the NDR1/HIN1-like protein-encoding gene was able to distinguish between common ash samples with different infection and symptomatic statuses. The SNP was a nonsynonymous substitution that would result in an amino acid change. The variation detected here may have an impact on pattern recognition and therefore affect the immune response, indicating tolerance/susceptibility to viruses of common ash. The identified marker may help in successfully identifying individuals with a low level of susceptibility to viral diseases.Open access funding provided by University of Sopron.University of SopronPeer Reviewe
Magnetoionography enhances diagnostic accuracy of magnetocardiography in coronary artery disease
No full textCoronary artery disease (CAD) remains a leading cause of morbidity and mortality worldwide. Traditional diagnostic approaches, including coronary angiography and electrocardiography, have limitations in detecting ischemia and microvascular dysfunction, leading to misdiagnoses and unnecessary interventions. This study evaluates the efficacy of magnetoionography (MIG), a novel parameter extension of magnetocardiography (MCG), in improving the detection of CAD by analyzing potential intracellular cardiac currents. We conducted a prospective study including 93 CAD patients and 36 healthy controls. All CAD patients underwent non-invasive MCG measurements before coronary angiography. Conventional MCG parameters were assessed alongside retrospectively together with the MIG-derived indices, focusing on the characterization of intracellular ion currents during repolarization. MIG analysis significantly improved CAD detection accuracy. The inclusion of MIG parameters in a stepwise linear discriminant analysis increased sensitivity from 90.3% (MCG alone) to 93.5% and specificity from 76.5 to 85.3%. Key discriminative parameters included Heart Rate, Current Moment Dynamics, and Dipolarity Index for ST Segment (all stress). Our findings support the further study of MIG for its potential use in clinical practice as a non-invasive, highly sensitive diagnostic tool for CAD. Through intracellular cardiac currents captured by an MCG system, the MIG parameter extension may offer deeper pathophysiological insights, potentially enhancing risk stratification and early disease detection.Open Access funding enabled and organized by Projekt DEAL.Humboldt-Universität zu Berlin (1034)Peer Reviewe
Rapid Behavior Recognition in Long-Term Recorded Home-Cage Mice
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Animal behavior is crucial for understanding both normal brain function and dysfunction. To facilitate behavior analysis of mice within their home environments, we developed DeepEthoProfile, an open-source software powered by a deep convolutional neural network for efficient behavior classification. DeepEthoProfile requires no spatial cues for either training or processing and is designed to perform reliably under real laboratory conditions, tolerating variations in lighting and cage bedding. For data collection, we introduce EthoProfiler, a mobile cage rack system capable of simultaneously recording up to 10 singly housed mice. We used 36 h of manually annotated video data sampled in 5 min clips from a 48 h video database of 10 mice. This published dataset provides a reference that can facilitate further research. DeepEthoProfile achieved an overall classification accuracy of over 83%, comparable with human-level accuracy. The model also performed on par with other state-of-the-art solutions on another published dataset ( Jhuang et al., 2010). Designed for long-term experiments, DeepEthoProfile is highly efficient—capable of annotating nearly 2,000 frames per second and can be customized for various research needs.Peer Reviewe
Reinforcement Learning Based Antenna Beam Selection for Wireless Communications in Urban Environments
No full textToday, machine learning has a crucial role in wireless communications, notably in 5G and 6G. It contributes significantly for increasing network capacity, improving user experience, and enhancing network reliability. Among machine learning techniques, reinforcement learning is vital due to its suitability for many real-world scenarios. It enables agents to learn from the environment with zero-knowledge and make rational decisions. Thus, in this article, we aim to explore the role of classical reinforcement learning in predicting optimal beam angles within urban environments. The goal is to minimize interference between antennas by finding optimal beamforming angles using ray tracing techniques. We examine various classic reinforcement learning methods in an urban scenario, focusing on maximizing total channel capacity. Initially, we identify the optimal beamforming angles for maximizing channel capacity with four antennas. After validating the learning methods and achieving over 99% accuracy, we proceeded to utilize them in a larger scenario. In the first phase, these methods and their accuracy are validated based on the results of the exhaustive search for a small number of nodes. In the second phase, we predict optimal antenna beam angles for scenarios with an increased number of transmitters and receivers for a realistic urban environment situated in the north-eastern part of Berlin.Open Access funding enabled and organized by Projekt DEAL.Humboldt-Universität zu Berlin (1034)Peer Reviewe
Cognitive flexibility in aging: the impact of age range and task difficulty on local switch costs in task switching
No full textIntroduction: Previous studies provided inconclusive results regarding the effects of aging on the ability to flexibly switch between task rules (local switch cost). The goal of the present study was to investigate the influence of age on the local switch costs at two levels of difficulty (easy task switching: two task rules vs. difficult task switching: four task rules). Methods: The local switch costs, i.e., reaction time and error differences between trials with a task switch and task repetition relative to the previous trial, were compared in a group of young adults (19 to 33 years) and three groups of older adults (64–72; 73–80; 82–97 years). Results: The analysis of the switch costs showed significantly higher switch costs of the three groups of older adults compared to the younger adults and the effect was more pronounced in the difficult task switching than in the easy task switching. At the same time, there were no clear differences in the local switch costs between the three groups of older adults. Discussion: The results showed that even after the age-related slowdown was taken into account, age differences in local switch costs will emerge when the age range of older adults is extended and task difficulty is sufficiently high. These findings contribute to our understanding of how and when age differences in cognitive flexibility emerge and suggest that complex multitasking environments may disproportionately challenge older adults.Peer Reviewe