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Les accueils de loisirs vus par les enfants : une désaffection annoncée ?
No full textInternational audienceThis article examines children's perspectives on their experiences of so-called 'collective' or 'organised' leisure activities in 'generalist' leisure settings such as leisure centres (formerly called 'centres de loisirs' or 'centres aérés'). Based on an analysis of the content of a digital platform that collects publications by groups of children reported by activity teams, the article presents how these perspectives are structured around several themes: the activities carried out, the importance of elective relationships, the role of play, the relationship with supervision and criticisms of the organisation. By reintegrating these perspectives into children's conceptions of leisure, the article provides a better understanding of how future, and juvenile, disaffection for these organised forms of leisure arose after the transition to secondary school.Cet article traite des perspectives des enfants à propos de leurs expériences de loisirs dits « collectifs » ou « organisés » au sein de structures de loisirs dites « généralistes » que sont les accueils de loisirs (anciennement centres de loisirs ou centres aérés). À partir d’une analyse du contenu d’une plateforme numérique publique recueillant des publications de groupes d’enfants rapportées par des équipes d’animation, l’article présente la façon dont se structurent ces perspectives autour de plusieurs thématiques : les activités réalisées, l’importance des relations électives, le rôle du jeu, le rapport à l’encadrement et les critiques opposées au fonctionnement. En réintégrant ces perspectives dans les conceptions enfantines du loisir, l’article permet de mieux comprendre comment se constitue dans l’enfance la désaffection juvénile pour ces modalités organisées de loisir suite au passage au collège
Optimal Dirac controls for time-periodic bistable ODEs, application to population replacement
No full textThis work addresses an optimal control problem on a dynamics governed by a nonlinear differential equation with a bistable time-periodic nonlinearity. This problem, relevant in population dynamics, models the strategy of replacing a population of A-type individuals by a population of B-type individuals in a time-varying environment, focusing on the evolution of the proportion of B-type individuals among the whole population. The control term accounts for the instant release of B-type individuals. Our main goal, after noting some interesting properties on the differential equation, is to determine the optimal time at which this release should be operated to ensure population replacement while minimizing the release effort. The results establish that the optimal release time appears to be the minimizer of a function involving the carrying capacity of the environment and the threshold periodic solution of the dynamics; they also describe the convergence of the whole optimal release strategy. An application to the biocontrol of mosquito populations using Wolbachia-infected individuals illustrates the relevance of the theoretical results. Wolbachia is a bacterium that helps preventing the transmission of some viruses from mosquitoes to humans, making the optimization of Wolbachia propagation in a mosquito population a crucial issue
Game Theory Meets Statistical Physics: A Novel Deep Neural Networks Design
No full textInternational audienc
Differences in mean daily intake of macronutrients, caffeine and water by level of mental morbidity
No full textInternational audienceWe investigated macronutrient, caffeine and water intake by mental morbidity level, focusing on pure and comorbid anxiety, insomnia, and eating disorders (ED). This descriptive, cross-sectional study used 2013-2017 data from the NutriNet-Sant & eacute; cohort. Diet was assessed with >= 3 24-hour records; mean daily intake of total energy and % contribution of carbohydrates, proteins, and lipids to total energy; total, simple, complex carbohydrates; total, animal, vegetable protein; total lipids, SFA, MUFA, PUFA; cholesterol; caffeine and water was analyzed. Data were weighted using the 2016 French Census, and ANOVA was performed (N = 23,965). Overall, men presenting all 3 mental disorders had the highest % carbohydrates and the lowest % proteins and lipids. The multimorbidity group had the highest obesity rates and caffeine intake across sex; water intake had no dose-response association with mental morbidity. The findings could help generate hypotheses regarding dietary exposures that might play a role in mental multimorbidity risk
Enhancement of Modelling and Testing Capabilities for Hydrogen Storage
No full textInternational audienceThe specificity of hydrogen storage research at LSPM, which recurrently secures high-level partnership conducive for project-based funding, stems from its historical core skills and resources in the field of high pressure. In terms of Technology Readiness Levels, the innovation-driven researchranges from TRL1 (predictive storage of functionalised graphene) [1,2] to TRL6 (test bench of pipe sections under real service conditions) [3,4]. On the one hand, the buffer storage of intermittent renewable energies has benefitted from the implementation of a test bench suitable for full scale-upwhich has been designed for testing pipe sections under monotonic or cyclic testing as required, for instance, for studying the dispatchability of a wind farm. On the other hand, solid-state hydrogen storage has benefitted from the implementation of high-pressure sorption devices up to 700 bar and of multi-scale modelling, including a revised intermolecular-hydrogen Hirschfelder model combiningvan der Waals’s and Coulomb’s forces [5] which has proved fully comprehensive and highlytransferable to activity fields such as the oil sector, the exploration of natural ‘white’ hydrogen resources, the hydrogen geological storage as well as the carbon capture and storage [6-9].References[1] F . D. Lamari, D. Levesque. Carbon, 49, 5196-5200 (2011)[2] P . L. Langlois, Ch. P . Chilev, F . D. Lamari. C, 12, 9 (2026).[3] L. Briottet, R. Batisse, G. de Dinechin, P . Langlois, L. Thiers. Int. J. Hydrogen Energ., 37, 9423-9430 (2012).[4] F . Lamari, B. Weinberger, P . Langlois, D. Fruchart. Hydrogen, 5, 387-402 (2024).[5] F . Darkrim, J. Vermesse, P . Malbrunot, D. Levesque. J. Chem. Phys., 110, 4020-4027 (1999).[6] N. Ferrando, P . Ungerer. Fluid Phase Equil., 254, 211-223 (2007).[7] J. Zhang, M. B. Clennell, D. N. Dewhurst. J. Phys. Chem. B, 127, 8900-8915 (2023).[8] Zh. Shang, Y . Yang, J. Li, Q. Zhang, L. Zhang, H. Sun, J. Zhong, K. Zhang, J. Yao. Geoenergy Sci. Eng., 257, 214215 (2026).[9] J. Zhang, M. Sayyafzadeh, R. Sander, M. Camilleri. Gas Sci. Eng., 147, 205832 (2026)
D-PerceptCT: Deep Perceptual Enhancement for Low-Dose CT Images
No full textInternational audienceLow Dose Computed Tomography (LDCT) is widely used as an imaging solution to aid diagnosis and other clinical tasks. However, this comes at the price of a deterioration in image quality due to the low dose of radiation used to reduce the risk of secondary cancer development. While some efficient methods have been proposed to enhance LDCT quality, many overestimate noise and perform excessive smoothing, leading to a loss of critical details. In this paper, we introduce D-PerceptCT, a novel architecture inspired by key principles of the Human Visual System (HVS) to enhance LDCT images. The objective is to guide the model to enhance or preserve perceptually relevant features, thereby providing radiologists with CT images where critical anatomical structures and fine pathological details are perceptually visible. D-PerceptCT consists of two main blocks: 1) a Visual Dual-path Extractor (ViDex), which integrates semantic priors from a pretrained DINOv2 model with local spatial features, allowing the network to incorporate semantic-awareness during enhancement; (2) a Global-Local State-Space block that captures long-range information and multiscale features to preserve the important structures and fine details for diagnosis. In addition, we propose a novel deep perceptual loss, designated as the Deep Perceptual Relevancy Loss Function (DPRLF), which is inspired by human contrast sensitivity, to further emphasize perceptually important features. Extensive experiments on the Mayo2016 dataset demonstrate the effectiveness of D-PerceptCT method for LDCT enhancement, showing better preservation of structural and textural information within LDCT images compared to SOTA methods.</div
Training in anterior and posterior zirconia cantilevered resin-bonded fixed dental prostheses: design and educational outcomes
No full textInternational audienceResin-bonded fixed dental prostheses, particularly zirconia-based single-retainer cantilever designs, offer a minimally invasive option for the replacement of anterior and, more recently, posterior teeth. This study aimed to develop a cost-effective reusable simulator and evaluate a one-day, simulation-based continuing education program grounded in current evidence for anterior cantilever (AC) and posterior cantilever (PC) zirconia resin-bonded fixed dental prostheses (RBFDPs)
Comparing modelled HIV incidence estimates with empirical HIV incidence observations in high-burden HIV African epidemic settings: systematic review and meta-regression
No full textAbstract Background HIV incidence in sub-Saharan Africa has declined substantially since 2000 according to epidemic estimates published by UNAIDS. These estimates, derived by fitting mathematical models to national surveillance data, guide HIV programmes and epidemic response strategies. We assessed whether the level and age distribution of HIV incidence from modelled estimates were consistent with empirical HIV incidence observations, and whether incidence levels and trends were systematically different between study types, populations, and age groups. Methods We conducted an updated systematic review of adult HIV incidence data from sub-Saharan Africa published July 2019-February 2024 by searching Scopus, PubMed, Embase, and OVID databases, and combined with earlier systematic review data. We matched empirical incidence measurements between 1990-2023 to UNAIDS HIV incidence estimates by study area, sex, age group, and year. We used Bayesian mixed-effect Poisson regression to estimate (1) incidence rate ratios (IRR) between empirical observations and matched modelled incidence estimates adjusted for sex, year and study type/population; and (2) time trends in age-specific incidence from population-based cohort studies and household surveys. Results 3560 HIV empirical incidence measurements were included from 179 studies conducted in 21 countries, comprising 23,000 new infections and 3.1 million person-years. Incidence observations from nationally-representative household surveys (IRR 1.07 95%CI 0.68, 1.67) and population-representative study populations (IRR 0.98 95%CI 0.51, 1.89) were not significantly different from matched modelled estimates, and declined at the same rate as modelled estimates (annual aRR 0.99 95%CI 0.98, 1.01). Studies among pregnant women (IRR 2.60 95%CI 1.58, 4.28), control arms of clinical trials (IRR 3.01 95%CI 1.90, 4.77) and key populations (FSW IRR: 6.46 95%CI 4.18, 10.00; MSM 44.02 95%CI 27.35, 70.87) had significantly higher incidence than modelled total population incidence estimates. Across population cohorts in Eastern and Southern Africa, HIV incidence among adults aged 15-49 declined by 75-90% between 2010-2023, and declined 7% (95%CI 4-10%) faster per year among young adults 15-24 compared to age 25+ years. Modelled incidence declined similarly to cohort data, but did not reflect the aging of the epidemic. Conclusion Observed incidence in population-representative studies in sub-Saharan Africa has declined steeply. Mathematical models that infer incidence from cross-sectional HIV surveillance data estimated the same incidence level and decline over time as population-representative studies. Studies with non-representative inclusion criteria had significantly higher incidence, including those among pregnant women and most HIV prevention/vaccine efficacy trials. The age pattern of incidence in modelled estimates should be reconsidered to capture the aging of the epidemic indicated by cohort studies