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Partir ou rester ? La mobilité des diplômés à l’épreuve des dynamiques économiques locales
No full textInternational audienceThe present article analyses the effect of social and territorial origin on geographic mobility choices of young people. The objective is to assess the extent to which local economic dynamics influence mobility at entry into higher education and the labour market, and to examine whether this effect varies according to social background. The 2017 Generation survey from Céreq is used to characterise individual mobility trajectories, supplemented with INSEE’s Labour Force surveys to provide a description of the local employment context. The results show that a favourable local economic situation, measured by an index capturing labour demand shocks, reduces post‑baccalaureate mobility; however, it has little or no discernible effect at the time of labour market entry. These effects are tempered by social background factors: young people with at least one parent employed at executive level are slightly more responsive to local economic conditions when joining the labour market.Cet article analyse l’effet de l’origine sociale et territoriale sur les choix de mobilité géographique des jeunes. L’objectif est d’évaluer dans quelle mesure les dynamiques économiques locales influencent la mobilité à l’entrée dans l’enseignement supérieur et à l’entrée sur le marché du travail, et de voir si cet effet varie selon l’origine sociale. Nous mobilisons l’enquête Génération 2017 du Céreq pour caractériser les trajectoires individuelles de mobilité, complétée par les enquêtes Emploi de l’Insee pour décrire le contexte local d’emploi. Les résultats montrent qu’une conjoncture économique locale favorable, mesurée par un indice captant les chocs de demande de travail, freine la mobilité post-baccalauréat, mais n’a que peu voire pas d’effet repérable au moment de l’insertion professionnelle. Ces effets sont modulés par l’origine sociale : les jeunes ayant au moins un parent cadre sont un peu plus réactifs aux conditions économiques locales à l’entrée sur le marché du travail
Concevoir un robot social et autonome à l'hôpitalApports de la notion de milieu pour la santé : théorie et méthode de conception
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Coupled Hydraulic-Geochemical Processes in a Faulted Clay-Rich Caprock: Reactive Transport Modelling of an In Situ CO2 Injection Experiment
No full textInternational audienceClay–rich formations are widely regarded as effective caprocks for geological CO2 storage; however, the presence of fractures in fault zone introduces significant uncertainty regarding their hydraulic behaviour during injection. In such settings, fluid migration is expected to be largely governed by fracture networks, while coupled hydraulic and geochemical processes associated with CO2–water–rock interactions may progressively modify hydraulic properties over time. This study presents a reactive transport modelling investigation of the CS–D (Carbon Sequestration – Series D) in situ CO2 injection experiment, with the aim of quantifying fracture hydraulic behaviour within a faulted clay–rich caprock.A three-dimensional reactive transport model has been fully implemented using HYTEC to simulate coupled fluid flow and CO2–water–rock interactions within a fractured fault zone embedded in a low-permeability clay matrix. The modelling framework accounts for aqueous speciation, mineral dissolution and precipitation, as well as advective–diffusive transport, and is configured to reproduce the experimental conditions of the CS–D test. Structural and hydrogeochemical observations derived from the experiment are used to constrain boundary conditions and initial states, while fracture hydraulic properties are treated as key uncertain parameters.The numerical framework enables a systematic investigation of the sensitivity of pressure evolution and geochemical responses to variations in fracture permeability and reactive surface area. The current geometric representation captures the principal structural characteristics of the faulted zone and retains sufficient flexibility to explore alternative conceptual configurations as the analysis progresses. The present work addresses coupled hydraulic and geochemical processes and is intended to serve as a basis for future extensions towards a coupled thermo-hydro-mechanical-chemical (THMC) framework relevant to subsurface energy applications.The resulting simulations are expected to provide quantitative constraints on the range of fracture hydraulic properties compatible with the hydraulic and geochemical signals observed during CO2 injection. Ultimately, this study seeks to improve the process-based understanding of fracture-controlled flow in faulted clay-rich caprocks and to support the interpretation of in situ experiments relevant to the long-term integrity and safety of geological CO2 storage and related geo-energy technologies
Penser le métier de préventeur par-delà ses compétences techniques
No full textInternational audienceLe préventeur a pour mission de veiller à la sécurité, à la santé des travailleurs et à la protection de l’environnement au sein d’une organisation. Son métier, loin de se limiter à la maîtrise de compétences techniques, exige également un esprit critique sur l’utilisation des outils et des méthodes, une pensée réflexive et une posture humaniste
Optimizing Distribution Planning with Long-Term Thermal Ratings in the Energy Transition
No full textThis paper investigates the significance of incorporating component thermal models in long-term electric distribution network planning. The study focuses on overhead lines, power transformers, and underground cables within medium and low voltage networks, considering stresses from distributed photovoltaic integration and electric vehicle charging stations. Two studies were carried out: a planning study is conducted in the medium voltage network, and a network performance indices calculation for the low voltage system. Both studies employed a probabilistic approach, using convolutional and Monte Carlo methods, respectively. Component thermal behavior was analyzed using quasi-Dynamic Thermal Ratings (qDTR) to maximize current-carrying capacity while controlling overcurrent risks. Weather data relative to the last 50 years in Sardinia were used. The results show that when qDTR is applied to urban distribution networks with a peak demand during evening-night hours, it eliminates the majority of overcurrent violations and reduces investment needs. On the other hand, in rural distribution networks influenced by the expansion of photovoltaic production, lower line and transformer ratings are correlated to peak production during hot sunny summer days, and qDTR correctly identifies this situation highlighting a slight increase in violations and network investments that would have been unchecked with less detailed approaches. Additionally, the long-term ratings calculated are more efficient in alleviating thermal constraints in areas with low exposure to high temperatures and solar radiation. This analysis highlights the trade-offs and benefits of applying qDTR across different network and geographic contexts.
Robust Pan-Cancer Mitotic Figure Detection with YOLOv12
No full textMitotic figures represent a key histoprognostic feature in tumor pathology, providing crucial insights into tumor aggressiveness and proliferation. However, their identification remains challenging, subject to significant inter-observer variability, even among experienced pathologists. To address this issue, the MItosis DOmain Generalization (MIDOG) 2025 challenge marks the third edition of an international competition aiming to develop robust mitosis detection algorithms. In this paper, we present a mitotic figure detection approach based on the state-of-the-art YOLOv12 object detection architecture. Our method achieved an F1-score of 0.801 on the preliminary test set (hotspots only) and ranked second on the final test leaderboard with an F1-score of 0.7216 across complex and heterogeneous whole-slide regions, without relying on external data
Characterization and modeling of continuous dynamic recrystallization (CDRX): Application to 2139 aluminum alloy
No full textInternational audienceControlling microstructure is a key factor in hot metal forming as it affects the performance of metallic materials. In high stacking-fault-energy materials, including aluminum alloys, continuous dynamic recrystallization (CDRX) drives microstructural evolution. In this study, hot compression tests were conducted on the AA2139 alloy across a wide range of thermomechanical conditions to (i) characterize the CDRX mechanism and (ii) generate experimental data for model calibration. Microstructural investigations were conducted to examine the development of grain and subgrain structures, and the evolution of disorientation distributions. Evidence of CDRX was observed through the formation of low-angle grain boundaries (LAGBs), their progressive increase in disorientation, and their transformation into high-angle grain boundaries (HAGBs), both in grain interiors and near original grain boundaries. Increasing strain promoted the progressive disorientation of LAGBs. Strain rate and temperature strongly influenced subgrain size, LAGB density, and dynamic recovery. Based on these results, a physically based CDRX model was developed by extending the work of Gourdet and Montheillet. The proposed improvements introduce the contribution of LAGB energy and disorientation angle to the subgrain-rotation law, a crystallite-size-dependent rate of LAGB creation through a refined physical description of the parameter , and the incorporation of self-heating effects during deformation. Together, these developments significantly enhance the physical consistency of the model. The overall experimental trends were reproduced, including the decrease in crystallite size and the increase in LAGB density at higher strain rates and lower temperatures, as well as the higher mean LAGB disorientation angle observed at lower strain rates. In addition, the model captures the macroscopic flow stress under various thermomechanical conditions
Deep Search for Joint Sources of Gravitational Waves and High-Energy Neutrinos with IceCube During the Third Observing Run of LIGO and Virgo
No full textInternational audienceThe discovery of joint sources of high-energy neutrinos and gravitational waves has been a primary target for the LIGO, Virgo, KAGRA, and IceCube observatories. The joint detection of high-energy neutrinos and gravitational waves would provide insight into cosmic processes, from the dynamics of compact object mergers and stellar collapses to the mechanisms driving relativistic outflows. The joint detection of multiple cosmic messengers can also elevate the significance of the common observation even when some or all of the constituent messengers are sub-threshold, i.e. not significant enough to declare their detection individually. Using data from the LIGO, Virgo, and IceCube observatories, including sub-threshold events, we searched for common sources of gravitational waves and high-energy neutrinos during the third observing run of Advanced LIGO and Advanced Virgo detectors. Our search did not identify significant joint sources. We derive constraints on the rate densities of joint sources. Our results constrain the isotropic neutrino emission from gravitational-wave sources for very high values of the total energy emitted in neutrinos (> erg)
In Situ Investigation of Plasticity Mechanisms of the Phase in (Ni, Pt)Al Bond Coats During Thermal Cycling by High-Energy X-Ray Diffraction
No full textEuroSuperalloys 2026 - 5th European Symposium on Superalloys and their applications, 03 au 07 mai 2026, GiensInternational audienceThe durability of thermal barrier coating (TBC) systems is strongly influenced by the interaction between oxidation of the metallic bond coat and its mechanical behavior. While the response of bond coats under isothermal monotonic loading has been widely studied, the effect of thermal cycling remains poorly understood, even though cyclic loading naturally arises from the mismatch in coefficients of thermal expansion between the ceramic top coat, thermally grown oxide, metallic bond coat, and the superalloy substrate. In this work, high-energy X-ray diffraction was used to investigate the strain and stress evolution in the -(Ni, Pt)Al bond coat of a standard TBC deposited on a nickel-based single-crystal superalloy during thermal cycling. Before in situ cycling, some of the studied specimens were aged through long furnace cycles. Strains and stresses in the phase were quantified in situ using the method combined with micromechanical modeling. The results reveal that plastic deformation in is strongly controlled by evolving interfacial effects and by the cyclic β ⇌ γ ′ phase transformation during thermal cycling. These mechanisms govern the accumulation of plastic strain in and may promote rumpling, spallation, and ultimately TBC degradation. This study provides new mechanistic insight into bond-coat plasticity under thermal cycling
Experimental evaluation of literature-established delignification techniques on poplar wood
No full textInternational audienceTo minimize greenhouse gas emissions, the development of biobased building materials is gaining increasing priority. Wood's insulation performance can be enhanced by creating additional porosity through the removal of non-cellulosic substances. Although delignification techniques have been used in the pulping industry to produce cellulose pulp, they have evolved to produce cellulose nanofibers or cellulose scaffolds for functional materials. Various top-down delignification techniques have been suggested for solid wood, but most studies have focused on a single technique applied to a specific wood species, making it difficult to compare the effectiveness of different methods. This paper addresses this gap by presenting a comparative analysis of literature-established delignification techniques applied to solid wood pieces: soda pulping, alkaline sulfite pulping followed by hydrogen peroxide bleaching, and organosolv pulping followed by sodium chlorite bleaching. This study evaluated the impact of these techniques by examining the changes in mass loss, chemical constituents and FTIR spectra of French poplar wood planks of 100 cm 3 after treatment. The combination of organosolv pulping by alcoholysis and sodium chlorite bleaching was found to be the most effective method for complete lignin removal. Our findings reveal the strengths and limitations of these methods, providing insights into the selection of wood modification techniques for upscaling purposes. Further research on drying delignified wood is required to complete a preliminary study of the industrialization of insulating wood. These advancements promoted the sustainable use of wood as a mechanically strong thermal insulator to reduce building energy consumption and mitigate climate change