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Empirical distribution of ancestral lineages in populations with density-dependent interactions
No full textWe study a density-dependent Markov jump process describing a population where each individual is characterized by a type, and reproduces at rates depending both on its type and on the population type distribution. We are interested in the empirical distribution of ancestral lineages in the population process. First, we exhibit a time-inhomogeneous Markov process, which allows to capture the behavior of a sampled lineage in the population process. This is achieved through a many-to-one formula, which relates the expected value of a functional evaluated over the lineages in the population process to the expectation of the functional evaluated along this time-inhomogeneous process. This provides a direct interpretation of the underlying survivorship bias, as illustrated on a minimalistic population process. Second, we consider the large population regime, when the population size grows to infinity. Under classical assumptions, the population type distribution converges to a deterministic limit.Here, we focus on the empirical distribution of ancestral lineages in this large population limit, for which we establish a many-to-one formula. Using coupling arguments, we further quantify the approximation error which arises when sampling in this large population approximation instead of the finite-size population process
Approximation theory for distant Bang calculus
No full textApproximation semantics capture the observable behaviour of λ-terms; Böhm Trees and Taylor Expansion are its two central paradigms, related by the Commutation Theorem. While well understood in Call-by-Name (CbN), these notions were only recently developed for Call-by-Value (CbV), motivating the search for a unified approximation framework. The Bang-calculus provides such a framework, subsuming both CbN and CbV through linear-logic translations while providing robust rewriting properties. We develop the approximation semantics of dBang-the Bang-calculus with explicit substitutions and distant reductions-by defining Böhm trees and Taylor expansion and establishing their fundamental properties. Via translations, our results recover the CbN and CbV cases within a single unifying framework capturing infinitary and resource-sensitive semantics
Vorticity-dependent and symmetry-preserving LES models
No full textInternational audienceWithin the Large Eddy Simulation framework, we propose a methodology based on the Lie theory to derive symmetry-preserving turbulence models. We apply this methodology to the incompressible Navier–Stokes equations. These models explicitly depend on both the filtered strain-rate tensor and the filtered vorticity tensor. Particular emphasis is placed on models that additionally ensure stability
Contribution of reed bed filter substrate’s microorganisms and vegetation to the biodegradation of road runoff organic micropollutants
No full textInternational audienceTo limit the impact of contaminated road runoff on the Seine River, the Paris municipality has set up an innovative reed bed filter (RBF) for runoff treatment composed of sand and a new commercial adsorbent named Rainclean (RC). To understand the fate of poorly studied contaminants from runoff retained by the RBF substrates, we evaluate the biodegradation of three emerging organic micropollutants (OMPs, bisphenol-A (BPA), 4-nonylphenol (4-NP) and 4-t-octylphenol (4-OP)) through experiments with planted (Phragmites australis) and unplanted columns of sand, RC and sediment. Results revealed that 60-99.6% of OMPs were degraded after 30 days, of which 68%-93% was attributable to microbial activity. BPA was the most rapidly degraded compound with half-lives (DT50) between 2.34-4.06 days (d) for sand and RC, compared to 2.55-15.6 d and 4.83-13.6 d for 4-NP and 4-OP respectively in all substrates. P. australis contributed to the biodegradation by increasing the percentage of total degradation for sand and RC and by decreasing the DT50 in sand. Physicochemical differences of the studied substrates and the presence of P. australis resulted in the development of distinct microbial communities, all being able to degrade the three OMPs. These results are crucial because they indicate a low risk of OMPs accumulation in RBF. However, sediment and unplanted RC showed high residual OMPs levels due to their adsorbent properties. Therefore, there is a risk of long-term accumulation of OMPs in these two substrates, requiring the monitoring of contents over time
Non-local aspects of cognition
No full textInternational audienceThis article explores the non-local aspects of cognition in two main directions, respectively contradicting the idea that 1) it exclusively refers to the cognitive subject's intrinsic mental aptitudes and that 2) it is exclusively centred on the subject’s spatial and temporal localisation. Following 4E cognition, the first direction mentions quite reasonable externalist and multiscale aspects of cognition by successively referring to Clark’s and Chalmers’ concept of extended mind, to social cognition, to Hutchins’ concept of distributed cognition and to Laurent’s multiscale enaction model. The second direction the concept of non-local cognition will be explored puts into question the spatio-temporal locality of cognition since it refers to the possibility of extra-sensory perception. The reality of extra-sensory perception is suggested by the non-reductive solutions to the problem of consciousness, and it is supported by very significant experimental results. The millenary interest in extra-sensory perception will be mentioned, with a special focus on Hinduism for its explicit reference in Pantanjali’s Yoga Sutra. Some of the significant experimental tests aimed to show its existence and some hints for building a theoretical modelling of it will then be presented. The reasons why the reality of extra-sensory perception is generally rejected by the scientific community despite numerous significant experimental results, as well as philosophical justifications and theoretical advances, will be discussed. This article pays particular attention to the second sense of ‘non-local’, based on the possibility of extra-sensory perception, insofar as this disturbing but rigorous scientific field of research is almost not at all considered by the current studies in cognitive science
Émergence d’un rôle frontière au sein d’un programme national piloté par Santé Publique France : le cas des chargé.es d’étude du programme national de surveillance du mésothéliome pleural
No full textInternational audienc
Violences conjugales : rétroactivité de l'absence d'exigence de cohabitation pour l'application de la circonstance aggravante de conjugalité
No full textInternational audienc
Prevalence of Patients With Pain Consulting Physiotherapists ( PHYSIODOL Survey). A Nationwide Survey in France
No full textInternational audienceABSTRACT Background Pain, whether as a symptom or a chronic disease, is the leading cause of medical consultations but there is no data on whether this is also the case in the practice of physiotherapy. Objective To assess the prevalence of patients with pain consulting a physiotherapist in France. Methods A questionnaire to be completed online was sent to physiotherapists practicing in France, asking them about the presence of pain in the patients they treated in the previous five days. The questionnaire was sent through representative healthcare organisations and professional societies, from January to September 2024. Results A total of 845 questionnaires were completed by physiotherapists, representing 52,497 patient consultations. Overall, 58.7% of patients seen by physiotherapists presented with pain, and pain was the main reason for consultation in 39.5% of patients. Physiotherapists reported a higher proportion of patients with chronic pain than with acute pain. Differences in pain characteristics were observed according to professional practice context: self‐employed physiotherapists more frequently reported pain located in the head or trunk and mixed acute and chronic pain profiles, whereas salaried physiotherapists more often reported acute pain and lower limb pain. Conclusion Pain is the major reason for physiotherapy consultations, and chronic pain is commonly encountered. Differences observed between self‐employed and salaried physiotherapists likely reflect variations in care contexts, referral pathways, and predominant fields of clinical activity. These results should inform health authorities of the role of physiotherapists in pain management and promote the development of standardised undergraduate and postgraduate pain education programs. Significance Statement This is the first nationwide and representative study to assess the prevalence and characteristics of pain among patients consulting physiotherapists. The results demonstrate that pain, particularly chronic pain, is a major reason for physiotherapy consultations in France. The evaluation of current educational programs and the implementation of standardised pain education for physiotherapists should now be undertaken to ensure best practices and ultimately improve patient outcomes
Intérêt de l'immunomarquage de la protéine GIRK4 dans la confirmation de l’origine glomérulée des lésions surrénaliennes observées chez des chats atteints d'hyperaldostéronisme primaire
No full textPrimary hyperaldosteronism (PHA) is an increasingly recognized endocrine disorder in ageing cats, characterized by autonomous aldosterone secretion by the adrenal cortex, leading to systemic hypertension and hypokalaemia. Diagnosis relies on a combination of clinical, biochemical, and imaging findings, but characterization of the underlying histological lesions remains challenging, particularly in the absence of formal histological criteria for zona glomerulosa hyperplasia. In this context, the objective of this study was to evaluate the relevance of GIRK4 immunolabeling (a potassium channel encoded by the KCNJ5 gene), physiologically expressed in zona glomerulosa cells, as a marker of glomerulosa cell identity in adrenal lesions associated with PHA. Adrenal tissues from 10 cats with PHA and 7 control cats were analysed using conventional histology combined with immunolabeling for GIRK4 and CYP17 (an enzyme absent from the zona glomerulosa and specific to the zona fasciculata). In control cats, GIRK4 expression was restricted to the zona glomerulosa, confirming its physiological localization. In PHA cats, GIRK4 expression varied according to lesion type: GIRK4- positive and CYP17-negative formations were interpreted as being of glomerulosa origin, whereas four lesions—including three adenocarcinomas—were negative for GIRK4. For three cases, including two adenocarcinomas, an incorrect diagnosis of PHA was excluded. Thus, the absence of GIRK4 labeling raises two main hypotheses: insufficient sensitivity of the antibody, or possible KCNJ5 mutations. The latter warrants investigation through targeted sequencing. Additionally, the use of complementary markers such as DAB2 could improve the detection of glomerulosa-derived cells when GIRK4 expression is weak or absent. We also observed variability in the organization of the zona glomerulosa according to age in healthy cats, suggesting age-related cortical remodeling with potential implications for the diagnosis of bilateral hyperplasia. Finally, although a GIRK4+/CYP17- immunophenotype is suggestive of a glomerulosa origin, it does not constitute formal evidence of aldosterone secretion. A better understanding of the interplay between CYP17 and CYP11B would be required to confirm the endocrine function of the identified lesions.L'hyperaldostéronisme primaire (HAP) est un trouble endocrinien de plus en plus diagnostiqué chez le chat âgé, caractérisé par une sécrétion autonome d'aldostérone par le cortex surrénalien, responsable d'hypertension artérielle systémique et d'hypokaliémie. Le diagnostic repose sur un faisceau convergeant d'arguments biologiques, cliniques et d'imagerie, mais la caractérisation des lésions histologiques causales reste un défi, notamment en l'absence de critères histologiques formels concernant les hyperplasies de la zone glomérulée. Dans ce contexte, ce travail visait à évaluer la pertinence de l'immunomarquage de GIRK4 (canal potassique codé par le gène KCNJ5), physiologiquement exprimé par les cellules de la zone glomérulée, comme marqueur d'identité cellulaire glomérulée des lésions causales d'HAP. Nous avons analysé les tissus surrénaliens de 10 chats atteints d'HAP et de 7 chats témoins, en combinant étude histologique classique et immunomarquages dirigés contre GIRK4 et CYP17 (enzyme absente de la zone glomérulée et spécifique de la zone fasciculée). Chez les témoins, le marquage GIRK4 était restreint à la zone glomérulée, confirmant son expression physiologique dans cette zone. Chez les chats HAP, nous avons observé une expression variable de GIRK4 selon le type de lésion : les formations GIRK4 positives et CYP17 négatives ont été interprétées comme d'origine glomérulée, tandis que quatre lésions, notamment trois adénocarcinomes, étaient négatives pour GIRK4. Pour 3 cas, dont 2 adénocarcinomes, la possibilité d'un diagnostic d'HAP erroné a été exclu. Ainsi, cette absence de marquage soulève principalement deux hypothèses : un défaut de sensibilité de l'anticorps, ou l'existence possible de mutations du gène KCNJ5. Cette dernière hypothèse mériterait d'être explorée par séquençage ciblé. De plus, l'utilisation de marqueurs complémentaires tels que DAB2 pourrait améliorer la détection des cellules glomérulées lorsque l'expression de GIRK4 est faible ou absente. Par ailleurs, nous avons observé une variabilité de l'organisation de la zone glomérulée selon l'âge des chats sains, suggérant une réorganisation corticale liée à l'âge, avec des implications potentielles dans le diagnostic d'hyperplasie bilatérale. Enfin, bien que l'immunomarquage GIRK4+/CYP17- soit évocateur d'une origine glomérulée, il ne constitue pas une preuve formelle de la sécrétion d'aldostérone. Une meilleure compréhension de l'interaction entre CYP17 et CYP11B serait nécessaire pour confirmer la fonction endocrine des lésions identifiées