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Optimizing Permanganic Acid Production: Effects of Temperature on Stability
No full textInternational audienceIn the nuclear industry, the decontamination of nuclear metallic structures is an essential process to reduce radiation exposure during maintenance or dismantling. The oxide layer, such as chromium (III) oxide (Cr2O3), formed on stainless steel and nickel-based alloys, contributes significantly to surface radioactivity by trapping radioactive contaminants. To address this, permanganic acid (HMnO4) has proven to be a promising oxidizing agent for dissolving these oxide layers—particularly chromium oxide—on stainless steel and nickel-based alloys. In this study, HMnO4 was synthesized via ion exchange using AmberLite IRN97 H resin and potassium permanganate (KMnO4). The optimized process yielded a highly acidic solution (pH~1.6) with potassium concentrations below 0.1 ppm, indicating near-complete exchange efficiency. Dissolution kinetics were investigated at HMnO4 concentrations ranging from 240 to 1920 ppm and temperatures from 30 °C to 80 °C. At a constant temperature, increasing HMnO4 concentration significantly improved Cr dissolution, with up to 31% of total chromium solubilized after 33 h. Lower temperatures favored higher dissolution efficiency, likely due to improved thermal stability of HMnO4. For durations shorter than 4 h, the influence of temperature was limited compared to the effect of acid concentration. To assess post-treatment options, HMnO4 decomposition was studied using oxalic acid (H2C2O4) at 80 °C. Results showed that a minimum H2C2O4/HMnO4 molar ratio above 2.75 was necessary to achieve effective reduction while preventing MnO2 precipitation. However, even under strongly acidic conditions and with a large excess of reductant, Mn2+ yields remained below 55%, suggesting that thermal degradation of oxalic acid and possible formation of undetected manganese species limited the reduction process.</jats:p
Un DSL pour représenter et analyser des systèmes à événements discrets *
No full textNational audienceIl existe de nombreuses approches (langages, techniques, outils) pour étudier (i.e. modéliser, analyser) des systèmes à événements discrets dans diérents contextes. Les langages généralistes, i.e. indépendant du contexte d'application, ont fait leur preuve en terme d'expressivité ou d'ecacité d'analyse, mais sourent de deux inconvénients. D'une part, ils pêchent à s'adapter à leur contexte d'application, on a donc besoin de spécialistes pour dénir et analyser les systèmes. D'autre part, les outils manquent de généralité quand à l'éventail des propriétés à démontrer, ce qui amène à utiliser diérents outils et nécessite donc encore plus de spécialistes pour un projet donné. Dans cet article, nous explorons l'usage de Domain-Specic Languages (DSLs) pour étudier des SED adaptés à leur contexte : dénition d'un langage, d'un outillage de modélisation et de vérication. Cette contribution est illustrée sur une étude de cas de production manufacturière pour alimenter empiriquement la réexion sur le sujet de l'accessibilité des langages de modélisation. Le langage est susamment générique pour s'adapter à d'autres contextes. 1 * Les auteurs remercient l'Agence Nationale de la Recherche (ANR) pour son soutien nancier dans le cadre du projet RODIC, numéro de subvention ANR-21-CE10-0017</div
Intrinsic motivation magnifies the effects of physical activity on perceived cognitive health
No full textPreprint uploaded on SportRχiv, preprint repository dedicated to sport, exercise, performance, and health research.International audienceObjective: Among its health benefits, physical activity improves cognitive health, but the strength of this association remains heterogeneous across studies. While previous research focused on structural factors of physical activity as potential moderating factors (e.g., duration, type), we aimed to examine whether the type of motivation (i.e., intrinsic versus extrinsic forms of motivation) could moderate the strength of the association between physical activity and cognitive health.Methods: Participants were 512 Canadian students (72% female and a mean age = 20 ± 5 years). Seven days after assessing their intrinsic and more extrinsic motivations toward physical activity, moderate-to-vigorous physical activity and perceived cognitive health were measured by questionnaire. Linear regression models were used to examine the moderating effect of motivation on the association between physical activity and cognitive health.Results: Intrinsic motivation moderated the association between moderate-to-vigorous physical activity and self-reported cognitive health (b = .12, = .04; .20, p = .004). As hypothesized, simple slope analyses showed that the association between moderate-to-vigorous physical and cognitive health was positive when intrinsic motivation was high (at sample mean + 1SD, b = .14, 95CI = .03; .25, p& .013), but not significant when intrinsic motivation was low (at sample mean - 1SD, b = -.09, 95CI = -.24; .06, p = .220). However, the moderating effect of extrinsic forms motivation was not significant (ps. > .071).Conclusion: In addition to structural aspects of physical activity, it is important to consider motivation toward physical activity when examining its effect on cognitive health
Tidal Deformation and Dissipation Processes in Icy Worlds
No full textInternational audienceAbstract Tidal interactions play a key role in the dynamics and evolution of icy worlds. The intense tectonic activity of Europa and the eruption activity on Enceladus are clear examples of the manifestation of tidal deformation and associated dissipation. While tidal heating has long been recognized as a major driver in the activity of these icy worlds, the mechanism controlling how tidal forces deform the different internal layers and produce heat by tidal friction still remains poorly constrained. As tidal forcing varies with orbital characteristics (distance to the central planet, eccentricity, obliquity), the contribution of tidal heating to the internal heat budget can strongly change over geological timescales. In some circumstances, the tidally-produced heat can result in internal melting and surface activity taking various forms. Even in the absence of significant heat production, tidal deformation can be used to probe the interior structure, the tidal response of icy moons being strongly sensitive to their hydrosphere structure. In the present paper, we review the methods to compute tidal deformation and dissipation in the different layers composing icy worlds. After summarizing the main principle of tidal deformation and the different rheological models used to model visco-elastic tidal response, we describe the dissipation processes expected in rock-dominated cores, subsurface oceans and icy shells and highlight the potential effects of tidal heating in terms of thermal evolution and activity. We finally anticipate how data collected by future missions to Jupiter’s and Saturn’s moons could be used to constrain their tidal response and the consequences for past and present activities
Rotating the Color Glass Condensate
No full textInternational audienceHigh-energy QCD evolution beyond leading order suffers from instabilities driven by large collinear logarithms. We present a framework, consistent with the standard high-energy operator product expansion (OPE), that restores perturbative stability order by order. The method involves a change of basis in the space of high-energy operators, which modifies both the evolution kernel and the coefficient functions while leaving physical observables invariant. Within this factorization scheme, we derive a next-to-leading-order renormalization-group equation whose numerical solution exhibits stable evolution up to large rapidities, thereby establishing a solid foundation for precision studies of gluon saturation at current and future colliders
RadioTransNet: Preclinical research network coordinated by the Société française de radiothérapie oncologique and Société française de physique médicale, 2025 update
No full textThis article is part of the special issue RecoRadTM, 4th edition on the 2025 update of the recommendations of the Société franc¸ aise de radiothérapie oncologique (SFRO) on external radiotherapy and brachytherapy proceduresInternational audienceThe RadioTransNet program, led by the Société française de radiothérapie oncologique (SFRO, the French society for radiation oncology) in association with the Société française de physique médicale (SFPM, the French society of medical physics), certified by the Institut du cancer (INCa, the French national cancer institute), was created at the end of 2018. The aim is to create a coherent, national, and multidisciplinary structure for preclinical and translational research in oncological radiotherapy by identifying research priorities. Its activities are coordinated by a scientific council, composed of radiation oncologists-therapists, medical physicists and academic radiobiologists researchers, and organized around four major axes which are: the definition of target volumes, the interaction of ionizing radiation with tissues, combined treatments and modern approaches to dose calculation. These four major axes are associated with different objectives concerning basic radiobiology, the studies of implementation of new drugs in preclinical settings, the contribution of imaging and new tracers, research in medical physics, by integrating a cross-cutting dimension of medical oncology and cost/effectiveness considerations. The selected themes form the basis for the projects studied and developed, taking into account the complementary skills of all the partner platforms involved in the network. Orientation proposals based on the priorities selected by the scientific council are submitted to INCa for the opening of dedicated calls to finance the human and technical resources necessary to conduct, under the best conditions, preclinical and translational research in radiotherapy
Violence sexuelle et mutilation dans la narration brève aux XVIe et XVIIe siècles
No full textInternational audienceDepuis qu’Ovide a raconté, dans Les Métamorphoses, l’histoire de Philomèle, violée puis mutilée par Térée qui lui a arraché la langue pour qu’elle ne puisse le dénoncer, viol et mutilation sont liés. Comme la langue arrachée, qui « frétille telle la queue d’un serpent mutilé » (Ovide), l’organe mutilé dit quelque chose du crime commis. Parce que le viol est un crime qui blesse et marque le corps, il appelle sans doute une réponse de même nature que l’acte initial. Pour un évêque comme Jean-Pierre Camus, l’automutilation jusqu’à la mort consentie, prend sens comme manière de re-sacraliser le corps souillé. « La sanglante chasteté » et « la brillante chasteté », deux histoires tragiques, mettent ainsi en scène une remédiation symbolique par la mort choisie, où la victime se fait martyre. Mais la violence appelée par le crime peut aussi se retourner contre l’agresseur : quand les femmes se vengent, elles n’hésitent pas à s’en prendre au corps qui les a meurtries, dans une loi du talion sans appel : si aucune ne va factuellement jusqu’à la castration du violeur, elles en proposent des formes indirectes très claires
Correction: Associations Among Diet, Health, Lifestyle, and Gut Microbiota Composition in the General French Population: Protocol for the Le French Gut – Le Microbiote Français Study
No full textInternational audience[This corrects the article DOI: 10.2196/64894.]
Suivi topo-morphologique de la queue de comète de l’île de Béniguet (période 2023-2025)
No full textEn parallèle de l’opération archéologique menée sur la dune de Porz ar Puns (Pailler et al., 2025), des campagnes de carottages et de mesures géophysiques ont été entreprises annuellement depuis 2021 afin d’étudier la couverture sédimentaire dans les parties terrestres de l’île de Béniguet. Ce travail vise à reconstituer l’évolution paysagère de cet espace insulaire sur la longue durée. Dans ce cadre, une attention particulière est portée sur la datation des dépôts sableux accumulés dans la queue de comète qui forme la partie nord de l’île. Pour être mené à bien, ce travail nécessite également de disposer d’une bonne connaissance de la morphologie actuelle de l’île et de données topographiques à haute résolution. C’est principalement pour ces raisons qu’une première mission de terrain a été réalisée au début du mois de septembre 2023, avec pour objectif d’acquérir des images aériennes au drone et d’obtenir un état topo-morphologique précis de ce secteur. Dans le même temps, ces données ont permis de suivre les dynamiques topo-morphologiques le long du trait de côte et de quantifier les phénomènes d’érosion sur l’ensemble de la queue de comète entre 2012 et 2023 (Stéphan et Stéphan, 2023). Seule la partie sud de l’île n’avait pas été levée jusqu’à présent. En août 2025, de nouveaux survols au drone ont donc été réalisés afin de combler cette lacune. Cette fois, l’ensemble de l’île a été survolée au drone. Les données recueillies permettent donc de poursuivre l’analyse des dynamiques érosives de l’île de Béniguet. L’objectif de ce rapport est de présenter ces données et de proposer un bilan des changements topo-morphologiques entre septembre 2023 et août 2025 le long de la queue de comète
PU.1 Shapes Host Epigenetic Responses to Mycobacterium tuberculosis and Represents a Target for Host Directed Therapy
No full textAbstract Mycobacterium tuberculosis ( Mtb ) infection induces widespread epigenetic changes in monocytes and macrophages. To characterize the critical factor responsible for Mtb -induced epigenetic responses, we performed an integrative analyses of chromatin modification (H3K27ac), transcription factor binding, and gene expression in human monocytes and macrophages. Our data identified PU.1 (SPI1) as a key transcriptional regulator to be upregulated and bound to gene promoters in response to Mtb . PU.1 enrichment was associated with enhanced proinflammatory and anti-apoptotic gene programs. PU.1 expression was also elevated in the lung tissues from Mtb -infected macaques and tuberculosis patients. PU.1 knockdown enhanced human macrophage apoptosis, dampened inflammation and reduced bacterial survival, suggesting its functional role in supporting Mtb infection. Pharmacological inhibition of PU.1 replicated the effects of knockdown, restricting Mtb growth without cytotoxicity. These findings identify PU.1 as a central node in the host epigenetic response to Mtb and a candidate for host-directed therapeutic targeting in tuberculosis