HAL-Université de Bretagne Occidentale
Not a member yet
75442 research outputs found
Sort by
Rapport 24-12. Déterminants et impacts de la qualité sanitaire de l’alimentation sur la nutrition et la santé humaines
No full textDisponible sur Internet le 22 decembre 2024 MOTS CLÉSQualité alimentaire ; Toxicologie alimentaire ; Innocuité sanitaire des aliments ; Xénobiotiques ; Limites maximales de résidus (LMR) ; Labels de qualité alimentaire Résumé Les composés potentiellement toxiques de l'alimentation font l'objet de larges débats contradictoires pour leurs effets sur la santé. Ils regroupent les xénobiotiques provenant de la pollution et des traitements de l'agriculture, les mycotoxines et les additifs utilisés dans la transformation des aliments. Le marché agroalimentaire européen est soumis à des réglementations plus contraignantes que les marchés américains et asiatiques, avec cependant une ouverture de plus en plus grande à la mondialisation des échanges. Un groupe de travail (GT) a auditionné des experts et acteurs du domaine pour approfondir trois questions : quels sont les enseignements et les limites de la toxicologie alimentaire ? La trac ¸abilité des sources et des modes de productions est-elle une réponse à l'enjeu de sécurité alimentaire face à la mondialisation ? Les labels de qualité alimentaire sont-ils suffisants pour assurer une information objective du consommateur sur la prévention du risque ? Le GT constate une ଝ Un rapport exprime une prise de position officielle de l'Académie nationale de médecine. L'Académie dans sa séance du mardi 26 novembre 2024 a adopté le texte de ce rapport par 64 voix pour, 3 voix contre et 4 abstentions.</div
"La face cachée des risques psycho-sociaux dans une entreprise adaptée : un impensé du management ?"
No full textInternational audienc
The Four Walls technique applied to citizen participation: An exploration of consistency effects
No full textInternational audienceIntroduction. -Citizens turn away from public debates because they are skeptical about their real impact. At the same time, although they do not know how to go about it, they are expressing a strong demand for participation. Compliance without pressure, and in particular Four Walls or Repeated Acquiescence (Cialdini and Sagarin, 2005), seem to be relevant tools if we want people to attend and then participate in debates.Objectives. -The aims of this article were: (1) to draw on this technique to develop an engagement strategy designed to bring people into the debate, and (2) to explore the theoretical explanations in terms of consistency used in this paradigm. Method. -Three studies were conducted (study 1, n = 60, study 2, n = 120, study 3, n = 102). Participants were invited to take part in an exchange meeting on social issues. The technique was systematically manipulated: cognitive consistency with the request vs. self-consistency (studies 1, 2 and 3) vs. unrelated to the request (study 2).Results. -The results of studies 1 and 2 show that the Four Walls technique is effective only when it is consistent with the request. The results of study 3 show that perceptions of exchange meetings are structured according to the type of consistency mobilized and the level of behavioral intention. Conclusion. -The technique appears to be a promising solution for fostering citizen mobilization within public debates. The adoption of this technique by concertation professionals could play an essential role in revitalising spaces for democratic expression in our societies. Nevertheless, the principle of consistency mobilized in this paradigm should be used with caution, at the risk of causing deleterious effects on the ability of individuals to truly exchange and listen to each other in these spaces.</div
Structural validity of the French version of the Child and Adolescent Scale of Participation (CASP-Fr) and factors influencing the participation of children with neuromuscular diseases
No full textInternational audienc
Explicabilité de séries temporelles : étude de cas sur des données de sécurité urbaine
No full textInternational audienceExplainability methods in artificial intelligence (XAI) have become essential for better understanding complex patterns, particularly in sensitive areas such as urban security. In this article, we study a governmental public dataset on crimes committed in France and implement an explainability method based on shapelets, distinctive subsequences that extract relevant information from time series of offenses. After transforming the problem for a supervised classification task, we aim to reveal patterns characteristic of crime. Nevertheless, data quality and availability represent a major challenge for model performance and interpretation. These findings illustrate the need to further open up resources and data in order to better understand and analyze urban security phenomena, an area that is not sufficiently accessible.Les méthodes d'explicabilité en intelligence artificielle (XAI) sont devenues essentielles pour mieux comprendre les modèles complexes notamment dans les domaines sensibles tels que la sécurité urbaine. Dans cet article, nous étudions un jeu de données public gouvernemental sur les crimes et délits commis en France et mettons en application une méthode d'explicabilité à base de shapelets, des sous-séquences distinctives qui ressortent les informations pertinentes de séries temporelles d'infractions. Après avoir transformé le problème pour une tâche de classification supervisée, nous cherchons à faire apparaître des motifs caractéristiques de la criminalité. Néanmoins, la qualité et la disponibilité des données représentent un défi majeur pour la performance des modèles et leur interprétation. Ces conclusions illustrent le besoin d'ouvrir davantage les ressources et les données afin de mieux comprendre et analyser les phénomènes de sécurité urbaine, un milieu encore trop peu accessible
The nasal microbiota of two marine fish species: diversity, community structure, variability, and first insights into the impacts of climate change-related stressors
No full textInternational audienceVertebrate nasal microbiota (NM) plays a key role regulating host olfaction, immunity, neuronal differentiation, and structuring the epithelium. However, little is known in fish. This study provides the first comprehensive analysis of the NM in two marine fish species, the European seabass and the Atlantic cod. Given its direct environmental exposure, fish NM is likely influenced by seawater fluctuations. We analysed the community structure, specificity regarding seawater, and interindividual variability of 32–38 fish reared under ambient conditions. Additionally, we conducted an experiment to investigate the influence of acidification and a simplified heatwave on cod NM (three fish per replicate). High-throughput 16S rRNA sequencing revealed species-specific NM communities at the genus-level with Stenotrophomonas and Ralstonia dominating seabass and cod NM, respectively. This suggests potential habitat- or physiology-related adaptations. The most abundant bacterial genera in seabass NM were also present in seawater, suggesting environmental acquisition. Alpha diversity was highest in Brest seabass NM and variability greatest in Tromsø cod NM. Simulated climate change-related scenarios did not significantly alter cod NM structure. We propose a minimum of 13 cod rosettes per replicate for future studies. This research establishes a foundation for understanding marine fish NM and its response to environmental changes
Perturbations of Vector Bundle whose Curvature Form Solves a Polynomial Equation
No full textWe investigate the behaviour of local perturbations of a wide class of geometric PDEs on holomorphic Hermitian vector bundles over a compact complex manifold. Our main goal is to study the existence of solutions near an initial solution under small deformations of both the holomorphic structure of the bundle and the parameters of the equation. Inspired by techniques from geometric invariant theory and the moment map framework, under suitable assumptions on the initial solution, we establish a local Kobayashi-Hitchin correspondence. A perturbed bundle admits a solution to the equation if and only if it satisfies a local polystability condition. We also show additional results, such as continuity and uniqueness of solutions when they exist, and a local version of the Kempf-Ness theorem. We also provide a local version of the Jordan-Hölder and Harder-Narasimhan filtrations
Polynomial Bridgeland Stability Conditions on the Category of Coherent Sheaves
No full textIn this short note, we provide a broad class of examples of stability conditions on the category of coherent sheaves which generalise Gieseker stability. We refer to them as "adapted to coherent sheaves" and they admit Harder--Narasimhan and Jordan--Hölder filtrations. We also study the particular case of Bayer's polynomial Bridgeland stability conditions, and their relation to the gauge theoretical counterpart introduced by Dervan--McCarthy--Sektnan
Generalized amoebas for subvarieties of
No full textThis paper is a report based on the results obtained during a three months internship at the University of Pittsburgh by the first author and under the mentorship of the second author. The notion of an amoeba of a subvariety in a torus has been extended to subvarieties of the general linear group by the second author and Manon. In this paper, we show some basic properties of these matrix amoebas, e.g. any such amoeba is closed and the connected components of its complement are convex when the variety is a hypersurface. We also extend the notion of Ronkin function to this setting. For hypersurfaces, we show how to describe the asymptotic directions of the matrix amoebas using a notion of Newton polytope. Finally, we partially extend the classical statement that the amoebas converge to the tropical variety. We also discuss a few examples. Our matrix amoeba should be considered as the Archimedean version of the spherical tropicalization of Tevelev-Vogiannou for the variety regarded as a spherical homogeneous space for the left-right action of
