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Le vieillissement démographique. Des espaces ruraux plus vieillis, une gérontocroissance urbaine accentuée
No full textNational audienceAgeing is a notable phenomenon, which has become more acute since the 2000s. Around one fifth of the French population is now aged 65 or over. At the local level, this is the result of declining fertility, longer life expectancy, the inherited age structure and migration. The proportion of elderly people is mapped at the level of counties or cities (‘cantons-ou-villes’), showing that it increases as population density decreases, a consequence of rural depopulation in the 20th century and the departure of young people for education or employment. The change in the proportion of older people is also mapped, highlighting how the coastal areas are ageing as a result of residential migration of senior residents. Furthermore, peri-urban areas as well as small and medium-sized towns have benefited most from the increase in the elderly population, while this trend remains limited in large urban and rural areas, where deaths do not sufficiently offset the number of people entering old age.Le vieillissement est un phénomène marqué, qui s’est accentué à partir des années 2000. Environ un cinquième de la population française a aujourd’hui 65 ans ou plus. À l’échelle locale, il résulte de la baisse de la fécondité, de l’allongement de la vie, de la structure par âge héritée et des migrations. La part des personnes âgées est cartographiée au niveau des cantons-ou-villes, montrant en premier lieu que celle-ci augmente à mesure que la densité démographique diminue, conséquence de l’exode rural au XXème siècle et du départ des jeunes pour les études ou l’emploi. L’évolution de la part des aînée est aussi cartographiée, illustrant le vieillissement des littoraux qui s’explique par des migrations résidentielles de personnes âgées. En outre , les espaces périurbains et les petites et moyennes villes ont le plus bénéficié de la gérontocroissance, tandis qu’elle demeure limitée dans les grandes agglomérations et les espaces ruraux, les décès y compensant insuffisamment les entrées dans le troisième âge
Combining physical and cognitive training to address cancer-related cognitive impairment: advantages and methods
No full textInternational audienceCancer-related cognitive impairment (CRCI) is a common side effect associated with cancer or its treatments and refers to a decline in cognitive function. Due to its complex and poorly understood causes, CRCI shows limited response to pharmacological treatments, prompting greater emphasis on non-pharmacological approaches. Combining physical and cognitive training has shown its effectiveness in reducing cognitive difficulties related to other pathologies, yet remains largely unexplored in cancer care. This commentary highlights the potential advantages of combining cognitive rehabilitation and physical activity for addressing CRCI and the potential need for further investigations of this combination in cancer care
Adoption et adaptation aux nouvelles pratiques de recherche de science ouverte et transparente chez les chercheur/es en psychologie
No full textInternational audienc
Enhancing environmental radionuclides tracking: High-resolution isotopic analysis using NanoSIMS
No full textInternational audienceHuman activities such as nuclear operations, and uranium (U), coal, and phosphate mining have induced the release of radionuclides into the environment, raising questions about their persistence and effects on populations and ecosystems due to ionizing radiation exposure. Understanding the sources, dispersion mechanisms, and spatiotemporal evolution of these contaminants is crucial for developing strategies to manage contaminated sites and associated waste. Traditional bulk sample analyses often conceal critical information about contamination sources because of isotopic mixing and/or concentration dilution caused by the matrix elements of the geochemical background. They also fail to precisely identify the nature and past evolution of radionuclidebearing phases. To overcome these challenges, microscale Secondary Ion Mass Spectrometry (SIMS and NanoSIMS) proves to be a suitable technique. This study focuses on the development of an analytical method for SIMS to trace contamination sources in Rophin’s wetland (France) impacted by U-mining and milling activities, and NanoSIMS to understand radionuclide mobility at the grain scale. Stable lead and uraniumdecay products (238U, 230Th, 226Ra) were calibrated with a natural autunite (Ca(UO2)2(PO4)2 • 10-12 H2O) mineral from Margnac (France) and synthesized barite (BaSO4) standards containing 2.89 and 9.65 mg.kg-1 226Ra. Additionally, this study introduces a novel approach for NanoSIMS data processing using spatial analysis tools from geostatistics. This enhances the interpretation of isotopic ratio distributions at the grain scale, offering insights into the mechanisms of radionuclide incorporation, stability, and mobility in complex environmental settings. Bulk soil analyses indicated an initial U-ore signature dominated by parsonsite (Pb2(UO2)(PO4)2) (206Pb/208Pb ≈ 0.48), with slight isotopic variations in certain soil layers (206Pb/208Pb up to 0.6), suggesting secondary contamination sources. SIMS analysis highlighted U-bearing phases (206Pb/208Pb ≈ ~9) inherited from pitchblende (UO2), a U-ore from Bois-Noir Limouzat that was also processed at the Rophin site. NanoSIMS provided new insights into the heterogeneous distribution of 238U, 226Ra, and 230Th within individual grains, distinguishing between newly formed and inherited U-bearing phases. These results bring information on processes governing radionuclides mobility (alteration, adsorption, precipitation). Finally, this work provides insights into the historical functioning of this wetland which can be considered in models predicting radionuclide mobility for future projection
Quality of life, psychosocial difficulties and bullying in paediatric patients with alopecia areata: a European cross-sectional study
No full textInternational audienceBackground: Alopecia areata (AA) is a chronic immune-mediated condition leading to nonscarring hair loss. Its visible nature often leads to stigmatization and bullying, which can negatively affect the mental health and quality of life (QoL) of adolescents.Objectives: To investigate the experiences of bullying, psychosocial challenges and QoL in adolescents with AA.Methods: This cross-sectional study included 417 participants aged between 10 and 17 years, with 156 adolescents diagnosed with AA from 6 European countries and 261 healthy German controls. Data collection involved validated questionnaires. These included the Revised Olweus Bully/Victim Questionnaire for bullying, the Strengths and Difficulties Questionnaire for psychosocial difficulties, and the Pediatric Quality of Life Inventory for QoL. Clinical data, including AA severity score, were also recorded. Statistical analyses employed parametric and nonparametric methods, including multivariate analysis of variance, Mann-Whitney U-tests, t-tests and correlation analyses.Results: Adolescents with AA reported significantly higher rates of general and verbal bullying, with hair loss and nail damage commonly identified as reasons for bullying. Girls experienced more emotional distress and bullying, while boys reported better emotional and social QoL. Physical functioning (i.e. limitations in physical activity, pain or low energy) was significantly lower in the AA group, although overall QoL differences were low. Longer disease duration was associated with greater emotional difficulties and reduced school functioning. No association was found with the age of the participant or the severity of the disease.Conclusions: Adolescents with AA often face significant challenges, including higher rates of bullying and emotional struggles compared with healthy controls. Developing targeted interventions to combat stigma and support mental and emotional wellbeing of paediatric patients with AA, in addition to a collaborative effort involving dermatologists, psychologists and educators could possibly make a meaningful difference in improving the QoL for these young individuals
Food and Terroir. Some experiences in France
No full textInternational audienceTerritorial Food Projects (TFSs) are based on a new political and legal paradigm: putting and regulating together agriculture, food and local development issues. This agriculture/food/territory triptych is the political foundation of the TFSs. It has been present from the start (2013), in the negotiations prior to the presentation of the bill on the future of agriculture and food and until the 2014 Law has been published. It constitutes the spirit of the law still today.The advent of this legislation led to a change in the socio-technical landscape of the food system (Geels 2011, Darrot and al. 2020b), based around a new paradigm - local food strategies - which “provide a forum for stabilising the norm and translating it into practice” (Darrot 2025). This norm provides more a legal open space where different stakeholders can discuss and act, than bidding rules. That is to say that the law contains very few substantive or procedural provisions to give freedom to the actors in the field concerned by each TFP (2). But this is only one side of the coin: TFSs are also controlled and managed by State. In other words, TFPs are hybrid in nature: they are managed and driven “from the top”, but developed and imagined “from the bottom” (Bodiguel 2020)
Intérêts et limites des échelles psychométriques dans l’étude des rapports entre santé et spiritualité
No full textInternational audienceThis article addresses the field of psychometric scales in the study of the relationship between health and spirituality. Psychometric scales have many advantages, but also disadvantages, some of which are presented here. The cultural dimension and the format of the questionnaires (implicit – explicit) are developed later. The conclusion addresses the question of the usefulness of the definition of the term “spirituality”.Cet article aborde le domaine des échelles psychométriques dans l’étude des rapports entre la santé et la spiritualité. Les échelles psychométriques présentent de nombreux avantages, mais aussi des inconvénients dont une partie est ici présentée. La dimension culturelle et le format des questionnaires (implicite – explicite) sont développés par la suite. La conclusion aborde la question de l’utilité de la définition du terme « spiritualité »
Named Data Networking for Scalable Distributed Storage and Indexation
No full textThis work is part of my postdoctoral research, which I am currently conducting within the framework of the STEEL project (PEPR Cloud – France 2030).With the exponential growth of data exchanged across geo-distributed infrastructures, the management, storage, and retrieval of such data have become major technical and economic challenges. One of the fundamental issues in data management systems is enabling users to quickly and efficiently access relevant information within massive and geographically dispersed datasets. In the geo-distributed context, several approaches have been proposed, including centralized and decentralized architectures, each with its own strengths and limitations. Centralized approaches simplify coordination but introduce single points of failure, potential bottlenecks, and limited tolerance to network partitioning. They can also increase data discovery costs, which may sometimes exceed the cost of retrieving the data. In contrast, decentralized approaches offer greater resilience and fault tolerance but often incur higher network overheads because of the need to propagate updates across the network whenever new data are created or modified. Therefore, designing an efficient indexing system remains challenging. Such a system should enable data discovery at a minimal cost without generating excessive network flooding while ensuring fault tolerance, high scalability, and independence from the geographical location of nodes. To address these challenges, we propose a fully distributed NDN-based storage architecture that integrates four complementary components: (1) VectorSync, a lightweight synchronization protocol that enables selective and dynamic update propagation across clusters; (2) NDNS, an indexation service that registers and resolves named content, enabling efficient replica discovery withoutnetwork flooding; (3) AS-cast, a partitioned dissemination mechanism that localizes the closest replica, therebyreducing inter-cluster traffic and overall network overhead; and (4) Hyperbolic Routing (HR), which guides packetforwarding decisions based on geometric coordinates, reducing routing table size and improving scalability. Together, these components ensure efficient data availability, consistent synchronization, and low-latency content retrieval across geo-distributed infrastructures, while minimizing network overhead
A Numerical Method for a Nonlocal Parameter Identification Problem
No full textInternational audienceThis paper addresses the inverse problem of identifying the time-dependent thermal conductivity in the one-dimensional parabolic heat equation from nonlocal overdetermination conditions. Such problems are typical in applications where only partial boundary data are available, leading to ill-posedness. We reformulatethe problem after time discretization in such a way that the integral boundary condition is used to decouple the search for the thermal conductivity coefficient from the solution of the parabolic equation. Haar wavelets are used to approximate the solution of the modified Helmholtz equation obtained from time discretization. A system ofalgebraic equations is obtained via collocation, providing an efficient computational framework for solving the problem
