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Epidemiology, pathophysiology, diagnosis and management of atrial functional mitral regurgitation: An expert opinion paper
No full textAtrial functional mitral regurgitation (AFMR) is an increasingly recognized subtype of mitral regurgitation, characterized by left atrial remodelling and mitral annular dilation in the absence of primary mitral valve disease or left ventricular dysfunction. Closely linked to chronic atrial fibrillation and heart failure with preserved ejection fraction, AFMR is associated with poor clinical outcomes and represents a growing therapeutic challenge. This expert opinion paper summarizes current evidence on the epidemiology, pathophysiology, diagnosis and management strategies, including medical therapy and emerging data supporting surgical and transcatheter interventions in selected patients. However, data from prospective controlled clinical trials are still lacking. Future research is needed to refine patient selection, long-term outcomes and to support evidence-based recommendations for this increasingly prevalent condition
Nonparametric serial interval estimation with uniform mixtures
No full textThe serial interval of an infectious disease is a key instrument to understand transmission dynamics. Estimation of the serial interval distribution from illness onset data extracted from transmission pairs is challenging due to the presence of censoring and state-of-the-art methods mostly rely on parametric models. We present a fully data-driven methodology to estimate the serial interval distribution based on interval-censored serial interval data. The proposed nonparametric estimator of the cumulative distribution function of the serial interval is based on the class of uniform mixtures. Closed-form solutions are available for point estimates of different serial interval features and the bootstrap is used to construct confidence intervals. Algorithms underlying our approach are simple, stable, and computationally inexpensive, making them easily implementable in a programming language that is most familiar to a potential user. The nonparametric user-friendly routine is included in the EpiDelays package for ease of implementation. Our method complements existing parametric approaches for serial interval estimation and permits to analyze past, current, or future illness onset data streams following a set of best practices in epidemiological delay modeling.OG and NH were supported by the VERDI project (101045989) and the ESCAPE project (101095619), funded by the European Union. Views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European Union or European Health and Digital Executive Agency (HADEA). Neither the European Union nor the granting authority can be held responsible for them. OG and NH acknowledge the financial support of the Fondation Universitaire de Belgique (file nr. AS-0608). OG and NH were also supported by the BE-PIN project (contract nr. TD/231/BE-PIN) funded by BELSPO (Belgian Science Policy Office) as part of the POST-COVID programme. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Gezondheidsscore voor stalen bruggen: een modelgedreven methode richting sensorgebaseerde evaluatie
No full textDe bestaande bruggen in Vlaanderen zijn sterk verouderd en behalen vaak hun beoogde levensduur niet, wat leidt tot stijgende onderhoudskosten en risico’s voor de veiligheid van weggebruikers. In samenwerking met Stadsbader Contractors NV ontwikkelt deze masterproef een scoringsmethodiek om de gezondheidstoestand van stalen bruggen objectief te evalueren, met als doel preventief onderhoud gericht in te plannen en de onderhoudskosten te beperken.
De methode werd ontwikkeld en gevalideerd aan de hand van een eindige-elementenanalyse in SCIA Engineer van de fietsbrug F214, onderdeel van het Diabolo-project. Structurele responsen en schadefenomenen zoals doorbuiging, trillingen en corrosie werden gesimuleerd in meerdere degradatiescenario’s doorheen de tijd. Op basis van deze parameters werd een gezondheidsscore toegekend aan afzonderlijke constructiedelen. Deze deelscores werden gecorrigeerd op basis van de leeftijd van de brug en samengevoegd tot één algemene score. De methode koppelt deze score aan concrete onderhoudsmaatregelen.
Uit de simulaties blijkt dat de gezondheidsscore afneemt naarmate de brug ouder wordt, waarbij de degradatie in de loop der tijd versnelt. Preventief onderhoud, voornamelijk aan de langs- en dwarsliggers, is cruciaal om de levensduur te verlengen en onderhoudskosten te verlagen. De methode biedt een snelle en objectieve manier om de onderhoudsurgentie en degradatie over de tijd in te schatten. Verder vormt dit onderzoek een basis voor toekomstig sensoronderzoek via de analyse van diverse sensortypes
Rethinking body representations in autism across cultures
No full textThe author(s) declare that financial support was received for the research and/or publication of this article. This study is supported by the University of Hasselt and University of Namur through the BOF program (R-13965)
Query Languages for Neural Networks
No full textWe lay the foundations for a database-inspired approach to interpreting and understanding neural network models by querying them using declarative languages. Towards this end we study different query languages, based on first-order logic, that mainly differ in their access to the neural network model. First-order logic over the reals naturally yields a language which views the network as a black box; only the input-output function defined by the network can be queried. This is essentially the approach of constraint query languages. On the other hand, a white-box language can be obtained by viewing the network as a weighted graph, and extending first-order logic with summation over weight terms. The latter approach is essentially an abstraction of SQL. In general, the two approaches are incomparable in expressive power, as we will show. Under natural circumstances, however, the white-box approach can subsume the black-box approach; this is our main result. We prove the result concretely for linear constraint queries over real functions definable by feedforward neural networks with a fixed number of hidden layers and piecewise linear activation functions.Funding Martin Grohe: Funded by the European Union (ERC, SymSim, 101054974). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. Christoph Standke: Funded by the German Research Foundation (DFG) under grants GR 1492/16-1 and GRK 2236 (UnRAVeL). Juno Steegmans: Supported by the Special Research Fund (BOF) of UHasselt. Jan Van den Bussche: Partially supported by the Flanders AI Program (FAIR
Infant buccal telomere length: Associations with maternal distress in pregnancy and offspring temperament
No full textIntroduction: Telomere length is considered a marker of biological ageing, and is shown to be susceptible to exposures during gestational and early life, including maternal psychological distress, and to be connected with temperament. Here, we examine the influence of maternal psychosocial and work-related factors on infant telomere length, and how infant telomere length is associated with infant and preschooler temperament.
Methods: 147 mothers and their offspring from the Dutch Prenatal Early Life Stress (PELS) cohort participated in this study. Psychological distress and work-related factors were assessed with the State Trait Anxiety Inventory (STAI), Edinburgh Depression Scale (EDS), Questionnaire on the Experience and Evaluation of Work (QEEW), and Copenhagen Psychosocial Questionnaire (COPSOQ) questionnaires at 16 – 23 gestational weeks. Offspring temperament was evaluated twice: first at 4 – 6 months using the Infant's Behavior Questionnaire (IBQ-R, very short form) and again at 4 years of age using the Children's behavior questionnaire (CBQ-R, very short form). Multivariable adjusted linear regression models were used to test associations between maternal psychosocial and work-related factors in pregnancy, infant buccal telomere length at 4 – 6 months after birth and infant and preschooler temperament, adjusting for maternal age, BMI, and education, and offspring age and sex.
Results: The PELS participants generally presented with low mental distress levels, with 9.5% of the participants having severe state anxiety scores and 5.4% of the participant having severe depression symptoms. Maternal STAI and EDS scores showed a positive correlation with preschooler negative affectivity. Maternal psychosocial and work-related factors exhibited no discernible associations with infant buccal telomere length (p's = 0.11). Additionally, infant buccal telomere length was not associated with offspring temperament. However, after adjusting for work-related stressors, social satisfaction showed a trend for significance on infant telomere length, with a 4.2% (95% CI: -0.31 to 8.76, p = 0.070) longer telomere length per 1 unit higher score in social satisfaction.
Conclusions: Higher satisfaction with social life may have a positive impact on infant telomere length. Mild maternal stress during pregnancy does not seem to affect infant telomere length, nor is telomere length predictive of infancy and early childhood temperament.Funding This study is supported by the Flemish Government within the framework of the Policy Research Centre Well-Being, Public Health and Family (Flanders, Belgium), The European Science Foundation supports the PELS cohort (EuroSTRESS-PELS-99930AB6-CAC-423B9527-7487B3308F3). BRHVdB. is financially supported by the European Commission Seventh Framework Programme (FO7-HEALTH. 2011.2.2.2-2 BRAINAGE, grant agreement no: 279281). DSM (FWO grant 12X9623N) is a postdoctoral fellow of the Flanders Research Foundation (FWP). Acknowledgments The researchers would like to thank Dr. Renée A Otte for helping with the recruiting of the participants, and all the PELS participants, researchers, students, midwives, and the staff of the maternity ward of Saint-Elisabeth hospital in Tilburg and the surrounding practices
Marine constraints as philosophical opportunities: the Krogh principle and the benefits of philosophical engagement with the sea
No full textThis paper shows how cases drawn from the marine sciences can be particularly fruitful for philosophical reflection about the nature of science. We offer a meta-philosophical adaptation of a heuristic (the Krogh Principle) taken from comparative biology, drawing connections between a problem common to both biology and philosophy of science: how to apportion scarce attention between the bewildering array of potential study systems? And how to do so in a way which recognises the diversity of those study systems, but preserves the possibility of generalisation? The Krogh Principle offers a heuristic: choose cases where the phenomenon of interest is demonstrated in an extreme or unusual way, so as to make the phenomenon particularly accessible. We follow one particular sub-strategy, namely, the exploration of cases which are subject to strong environmental constraints, which we expect to be as fruitful in the choice of organisms as it is for scientific case studies. Marine sciences offer examples of substantial environmental constraints on scientific practice, and so present extreme and unusual examples from which philosophers can improve existing conceptual machinery to the benefit of both philosophers and scientists. In particular, we use examples from coral reef and deep-sea science to show how marine sciences can both reinforce and refine philosophical understanding of the role played by values in science. We conclude by suggesting that many other topics-in both philosophy and science-may also stand to benefit from philosophical engagement with environmentally-constrained or otherwise unusual case studies, in particular cases taken from the marine sciences.Funding
Elis Jones’s research was funded by the Economic and Social Research Council via the South West Doctoral Training Partnership, the University of Exeter, Offenham Old School Trust, and the Konrad Lorenz Institute for Evolution and Cognition Research. The research of Vincent Cuypers for this paper was funded by the Research Council—Flanders (project G0D5720N)
Enhancing MoQ Visibility Using a Modular Logging Infrastructure
No full textTerwijl het landschap van mediastreaming evolueert, bieden opkomende protocollen zoals Media over QUIC (MoQ) nieuwe mogelijkheden om uitdagingen aan te pakken die inherent zijn aan bestaande oplossingen zoals WebRTC en HTTP Adaptive Streaming. Terwijl deze traditionele methoden ofwel lage latentie bieden ten koste van schaalbaarheid, ofwel schaalbaarheid leveren met verhoogde latentie, streeft MoQ naar een evenwichtige aanpak door gebruik te maken van QUIC’s gemultiplexte en betrouwbare transportfuncties gecombineerd met publiceer-abonneer-modellen en prioritering.
De adoptie van MoQ stuit echter op hindernissen, met name vanwege de complexiteit bij het debuggen en monitoren, veroorzaakt door de dynamische structuur en asynchrone besturingsberichten. Om deze uitdagingen te overwinnen, introduceert deze thesis een schaalbaar, webgebaseerd logging- en visualisatieframework dat specifiek ontworpen is voor MoQ. Dit systeem is gebaseerd op het gestructureerde qlog-formaat, oorspronkelijk ontwikkeld voor QUIC en HTTP/3, en wordt uitgebreid om MoQ-specifieke semantiek te ondersteunen. Hiermee wordt de observeerbaarheid en operationele inzichtelijkheid in het gedrag van het protocol aanzienlijk verbeterd.
Deze thesis presenteert een uitgebreide aanpak om de observeerbaarheid van MoQ te vergroten door het ontwerpen en implementeren van een gestructureerd loggings- en analysesysteem. Een belangrijke bijdrage is de definitie van een qlog-uitbreidingsschema dat specifiek is afgestemd op het vastleggen van de semantiek van MoQ. Deze u