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Le patrimoine universitaire dans son territoire : l’exemple de la Bourgogne – Franche-Comté: Version enrichie en ligne : https://una-editions.fr/villes-et-universites/
No full textInternational audienc
ATICC : a mixed-methods study on addiction, trauma, and immigration among vulnerable young adults in the grand est youth network
No full textInternational audienceBackground : This research protocol for the study ATICC (Addiction, Trauma and Immigration, prevention and Cross-Cultural support for care with the Grand Est youth network) aims to model the complex interrelations between trauma, substance use behaviors, migration and representations of mental health among vulnerable youth residing in Transitional Housing for Young Adults. This study focuses on a specific and underexplored population, many of whom have experienced traumatic events and/or complex migratory trajectories. The ultimate objective of this research is to develop transferable models of understanding that can inform the design of prevention and support programs tailored to this demographic. Methods/Design We adopt a tripartite methodology approach: (1) a cross-sectional study using standardized questionnaires to identify factors associated with substance use, trauma, and barriers to healthcare access; (2) an in-depth qualitative study based on semi-structured individual interviews with substance users, exploring their subjective experiences and perceptions related to substance use and mental health care; and (3) a longitudinal interventional study involving various configurations of focus groups open to residents of transitional housing structures, aiming to assess the impact of these group sessions on participants’ psychological well-being and attitudes toward care. Quantitative analyses will include descriptive and multivariate statistical tests using R, while qualitative data will be analyzed through thematic analysis with NVivo. The effectiveness of the group intervention will be evaluated using pre/post-tests, mixed models, and appropriate statistical corrections. Discussion Analyses are expected to identify key psychosocial factors influencing addictive behaviors and mental health, highlight cultural and structural barriers to care, and assess the psychological benefits of the group intervention. The ATICC study aims to contribute to the development of culturally adapted prevention and support models for young adults in precarious situations. The results should assist healthcare professionals and policymakers in designing evidence-based interventions that effectively address the specific needs of this population. Trial registration This study is registered with the Biomedical Research Identification Number (n°ID-RCB) assigned in France by the National Agency for the Safety of Medicines and Health Products (ANSM): 2024-A01534-43, and have received the approval from the committee for the protection of persons (CPP) Ile-de-France on November 18, 2024. Cette étude a également été déposée sur clinicaltrials (NCT06922721, date assigned April 10, 2025)
Unintended patterns emerging from a declining creative hub: three critical moments of organizationality
No full textThème du congrès : « Creativity that Goes a Long Way »International audienc
Elasticité au second-gradient de la déformation pour les matériaux cubiques centro-symétriques
No full textInternational audienceNous nous intéressons dans ce travail à l’élasticité linéaire du second gradient de la déformation formulée dans R3. Sous l’hypothèse de centro-symétrie du milieu matériel, cette loi de comportement est définie par une famille de tenseurs dont les ordres pairs varient entre 4 et 8. Nous posons ici la question du paramétrage optimal de cette famille dans le cas d’un milieu à symétrie cubique dont le groupe ponctuel est O × Z2 (m3m en notation d’Hermann-Mauguin). Ce paramétrage permet de donner un contenu physique aux 49 paramètres matériaux et 2 modules de cohésion qui contrôlent la relaxation anisotrope de surface. Nous avons ensuite étudié la relaxation de surface pour quelques orientations<br>cristallines et comparés les champs ainsi calculés aux champs expérimentaux obtenus par diffraction des électrons lents. Cette étude ouvre donc la voie à l’interprétation mécaniques de nombreux résultats expérimentaux obtenus dans le champ de la physique des surfaces
Placement institutionnel, en famille d’accueil ou en accueil mère-enfant : Le point de vue des nourrissons
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Nanofiber platform to manipulate photons and phonons
No full textInternational audienceBrillouin scattering has found extensive applications in advanced photonics functions, including microwave photonics, signal processing, sensing, and lasing. More recently, it has been employed in micro- and nano-photonic waveguides [1]. Tapered optical fibers, due to their small transverse dimensions, exhibit a range of optical and mechanical properties that render them highly attractive for both fundamental physics research and technological applications. In contrast to standard telecom fibers, where Brillouin scattering is characterized by a single Lorentzian resonance centered at 10.86 GHz (@ 1550 nm), tapered silica fibers exhibit multiple Brillouin resonances at various frequencies ranging from 5 GHz to 10 GHz, originating from surface, shear, and compression elastic waves (see Figure 1a) [3]. For a large evanescent optical field surrounding the nanofiber, we observe an efficient Brillouin scattering in gas [4]. We show drastic Brillouin scattering enhancement by increasing the gas pressure with a maximum Brillouin gain which is 79 times larger than in a SMF (fig 1.b) [4]
Protocoles expérimentaux pour comprendre la dégradation accélérée d’un électrolyseur PEM
No full textNational audienceLa technologie d’électrolyse PEM est l’une des technologies les plus prometteuses pour la production d’hydrogène verte. L’étude détaillée de sa dégradation est donc un domaine d’étude fondamental pour réduire le coût et améliorer la durée de vie. Contrairement aux piles à combustible PEM, les études sur la dégradation des électrolyseurs sont moins nombreuses, c’est pourquoi ce travail propose des protocoles expérimentaux qui visent à observer et étudier la dégradation dans des conditions de stress qui peuvent accélérer ces mécanismes. Avec un taux de dégradation de 36.5 uV/h pour une mono-cellule et de 18 uV/h/cell pour un short-stack, les expériences prouvent dans les deux cas que : la température peux avoir effet très important sur la dégradation du catalyseur cathodique et la membrane, le cyclage du courant àtrès basse fréquence régénère les conditions électrochimiques, les densités de courant élevées sont les plus pénalisantes et une grandepartie des pertes peut être récupérée avec une période de repos adaptée. Trois pics ont été identifiés dans l’analyse DRT : (P1) la cinétique de la réaction d’évolution de l’oxygène, (P2) le transport de charge de l’électrode, et (P3) le transport ionique
Two-dimensional steady-state thermal analytical model of permanent magnet linear motor in Cartesian coordinates
No full textInternational audienceCompared with the time-consuming numerical method and the complexlumped parameter thermal network method to solve the steady-stateheat distribution of the permanent magnet (PM) linear motor, thereis no analytical method based on the thermal partial differentialequations. This paper aims to propose a two-dimensional (2-D)analytical model for predicting the steady-state temperaturedistribution of PM linear motors to improve the prediction accuracyand speed up the calculation. Design/methodology/approach Based onthe complex Fourier series theory and Cauchy’s product theorem,this paper presents for the first time a general analyticalsolution for 2-D temperature field in Cartesian coordinates. Then,by combining the electromagnetic field finite element model (FEM),the copper loss, iron loss and PM eddy current loss are used as theheat sources of the thermal analytical model. Finally, the solutionto the temperature field is obtained by solving the system equations under boundary and interface conditions. Findings Theanalytical results are in good agreement with those from thethermal FEM, and the calculation speed is significantly faster thanthat of the thermal FEM. Originality/value The multilayer modelproposed in this paper can consider heat conduction, convection andradiation. It is not only suitable for PM linear motors but alsohas significant application value for the thermal analysis ofelectromagnetic devices modeled in 2-D Cartesian coordinates
Thin layer deposition of TiO2 and PMMA on optical micro or nano fibers for nonlinear optics
No full textInternational audienceOver the last twenty years, silica optical tapered micro or nanofibers (called ONF in the following) have been widely exploited for a large range of potential applications in several areas of research for their original properties of light propagation. The high confinement of the optical mode in the uniform part and the presence of a strong evanescent field near the surface make them devices of choice for nonlinear applications. In this paper we study the coating of ONF with nonlinear materials to expand further the possibilities offered by these devices. Two materials are chosen for the coatings, Titanium Dioxyde (TiO2) and Polymethyl Metacrylate (PMMA). Two processes have been developed for the coatings. Firstly, Atomic Layer Deposition has enabled to deposit controlled thin layers of TiO2 of several tens of nm on an ONF having a diameter of 1 μm with very low additional losses (0.5 dB). Secondly, we have realized a multiple layer deposition process to deposit PMMA layers on ONF. With this technique we were able to reach thicknesses of about 100 nm on ONF diameters as small as 1 μm. The encapsulation of a coated tapered fiber in silicone has been conducted, resulting in minimal additional losses, showing great promises from such a treatment. These initial experimental proofs of concept open the way for further experiments in nonlinear optics using functionalized ONF. Potential applications include the development of Raman converters within the evanescent field of the optical propagating mode, as well as experiments that necessitate precise control of phase matching