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Empowerment et aspirations des femmes dans le commerce équitable. Une analyse qualitative dans le textile en Inde
No full textInternational audienceSi les analyses d’impact du commerce équitable se sont multipliées ces deux dernières décennies, très peu a été produit sur ses effets en termes d’empowerment. Nous en proposons une analyse qualitative dans le secteur du textile en Inde. Ce secteur réputé pour ses mauvaises conditions de travail ne fait, de plus, l’objet de quasiment aucune analyse dans les travaux sur le commerce équitable. Nous ajoutons les aspirations des employées à notre étude. Notre analyse questionne donc la relation entre empowerment et changement dans les aspirations des femmes et montre que, si des effets multiples existent, les aspirations portent plutôt sur des changements pour les générations futures, en particulier les filles des femmes employées dans le commerce équitable
Experimental fatigue characterization and modeling of a bi-component structural acrylic adhesive: Application to single-lap joints
No full textInternational audienceThe aim of this paper is to predict the fatigue behavior of bonded joints made of a bi-component structural acrylic adhesive. The approach considered is based on a characterization of the fatigue properties of the bulk adhesive combined with a finite element modeling of the bonded joint to provide the heterogeneous stress field within the adhesive. The identification of the fatigue model is conducted with experimental bulk adhesive tests under two loadings (tensile–compression and tensile–tensile) in order to account for the effect of the mean stress. A modified Crossland criterion, in the limited life time domain, is used to predict the fatigue life of the bonded joint assembly. The numerical fatigue life determined with this approach is compared to the experimental fatigue life of the assembly. A good correlation is found between the numerical model and the experimental results
Oriented networks of gold nanorods in smectic topological defects
No full textInternational audienceA liquid crystal (LC) is a mesophase where the molecules are free to move as in a fluid, but show a certain degree of order as in a crystal lattice. Under specific conditions, a thin film of smectic LC can form a pattern of flattened hemicylinders that present different kinds of topological defects (1D and 2D defects) strictly oriented along the hemicylinders direction. These defects are able to confine nanoparticles (NPs) [1], leading to NP networks that are well oriented along the defects [2]. Our aim is to exploit the intrinsic order of this LC matrix to create plasmonic composites with gold nanorods coated with thiol-terminated polystyrene.Methods: We investigate the optical properties of the composite measuring light absorption polarizing the incident light either parallel and perpendicular to the hemicylinders. Absorption spectra are combined with FDTD simulations and X-ray diffraction experiments performed in a transmission configuration at synchrotron facilities.Results and discussion: Absorption measurements reveal that these nanorods self-assemble side-to-side, either perpendicular or parallel to the hemicylinders. The well-defined orientation of these networks imposed by the flattened hemicylinders orientation provides the composite with polarized plasmonic properties (see figure). We show that by playing with the LC’s thickness and the nanorod concentration we can modulate the side-by-side assembly anisotropy, eventually leading to almost perfectly oriented nanorods as confirmed by X-ray diffraction measurements. Comparing the results with FDTD simulations, the plasmonic light absorption is in agreement with the formation of small assemblies of oriented nanorods, where the absorption wavelength appears strongly dependent on the size and shape of the assemblies.*****References:[1] Do, Nano Letters 20,3,1598-1606 (2020).[2] Jeridi et al. Soft Matter 18, no. 25 (2022): 4792–480
Coherent spin manipulation in mononuclear gadolinium-substituted polyoxometalate–organic hybrids
No full textInternational audienceWhile most research on molecule-based electron spin qubits has focused on S = 1/2 ions for single-qubit gates, the need for qubit interactions in quantum operations has driven interest in higher-spin molecules and multilevel states. Herein, we study the spin dynamics of two mononuclear gadolinium-substituted polyoxometalate-organic hybrids with the general formula K5[Gd(α-XW11O39)(H2L)] · 14H2O (X = Si, Ge; H2L = N,N′-dimethyl-N,N′-bis(2-hydroxy-3-formyl-5-bromobenzyl)ethylenediamine), 1Si-Gd and 1Ge-Gd. Pulsed EPR measurements reveal spin–lattice relaxation (T1) and quantum coherence (Tm) times of up to 2315 and 2.6 μs at 3 K, respectively, for diamagnetically diluted samples, as well as Rabi oscillations up to 20 K. The obtained results make 1Si-Gd and 1Ge-Gd two of the few Gd-based complexes displaying such behavior, highlighting the challenge of coherently manipulating the spin states of Gd. Moreover, their hybrid organic–inorganic nature endows them with chemical robustness and solution stability, essential prerequisites for surface immobilization and future integration in practical devices
Évaluation des discordances en sérologie aspergillaire et bilan de dix ans d'expérience au CHU de Bordeaux
No full textChronic pulmonary aspergillosis represents a major health challenge due to its morbidity. Diagnosis is often based on an enzyme immunoassay (EIA), followed by confirmation using Western Blot (WB). However, the diagnostic thresholds for EIA vary across studies. This retrospective study, conducted over ten years, aims to evaluate the diagnostic performance of Aspergillus serology and its evolution over time. Materials and Methods: this is a single-center retrospective study conducted between January 2015 and June 2024. We analyzed 16,674 serological tests performed using Bio-Rad ELISA on 8,089 patients, of whom 4,457 underwent additional testing with WB (LDBIO). A total of 1,034 patients were included in the serological follow-up. Forty-seven serum samples (from 39 patients) with a discordant serological profile (Bio-Rad ELISA ≥ 5 UA/mL and negative WB) were included. Anti-Aspergillus IgG antibodies were tested using EIA techniques (Bio-Rad, ImmunoCap, and Bordier) and WB (LDBIO). Results and discussion: serological tests performed using Bio-Rad and WB LDBIO were concordant. An optimal threshold of 0.4 UA/mL in Bio-Rad was determined (sensitivity 73%, specificity 82%). Serological follow-up analysis showed remarkable stability of WB over time. The semi-quantification method appears to be confirmed. Correlation analysis among the three EIA techniques was consistent with findings from the literature. These data still need to be consolidated to validate the benefit of using a complementary technique to Bio-Rad ELISA (Bordier or ImmunoCap tests), in addition to WB.Les aspergilloses pulmonaires chroniques représentent un enjeu de santé majeur en raison de leur morbidité. Le diagnostic repose fréquemment sur une méthode immuno-enzymatique (EIA), suivie d’une confirmation par Western Blot (WB). Toutefois, les seuils diagnostiques des EIA varient selon les études. Cette étude rétrospective, réalisée sur dix ans, a pour objectif d'évaluer les performances diagnostiques de la sérologie aspergillaire et son évolution au cours du temps. Matériels et méthodes : il s’agit d’une étude monocentrique rétrospective entre janvier 2015 et juin 2024. Nous avons analysé 16 674 sérologies réalisées en ELISA Bio-Rad sur 8 089 patients, dont 4 457 ont été complétées par un WB (LDBIO). 1034 patients ont été inclus dans le suivi sérologique. 47 sérums (39 patients) présentant un profil sérologique discordant (ELISA Bio-Rad ≥ 5 UA/mL et WB négatif) ont été inclus. Les IgG anti-Aspergillus ont été recherchées par technique EIA (Bio-Rad, ImmunoCap et Bordier) et WB (LDBIO). Résultats et discussion : les sérologies réalisées en Bio-Rad et WB LDBIO étaient concordantes. Un seuil optimal de 0,4 UA/mL en Bio-Rad a été déterminé (sensibilité 73 %, spécificité 82 %). L’analyse du suivi sérologique montrait une très grande stabilité du WB dans le temps. L’intérêt de la semi-quantification du WB semble se confirmer. Les résultats des analyses de corrélation entre les 3 techniques EIA étaient en accord avec ceux retrouvés dans la littérature. Ces données restent à consolider afin de valider l'intérêt d'utiliser une technique complémentaire à l’ELISA Bio-Rad (tests Bordier ou ImmunoCap), en plus du WB
Associations Between Adverse Childhood Experiences and Prenatal Mental Health in the French EDEN Cohort: Cumulative, Person-Centered, and Dimensional Approaches
No full textInternational audienceAdverse childhood experiences (ACEs) may negatively affect prenatal mental health. However, the use of a cumulative ACEs score may obscure the identification of which specific types of adversity are most strongly associated with unfavorable mental health outcomes. Aim: This study aims to evaluate the association between ACEs and prenatal symptoms of depression and anxiety using a cumulative score, a person-centered approach, and the dimensional model of adversity and psychopathology (DMAP). Methods: Data were collected from 1887 pregnant women in the French Etude des Déterminants du développement et de la santé de l'ENfant (EDEN) cohort. To operationalize our exposure, we calculated a cumulative ACE score, threat and deprivation scores, and conducted latent class analysis (LCA). Depressive and anxious symptoms were assessed with the Center for Epidemiologic Studies-Depression Scale (CES-D) and the State-Trait Anxiety Inventory state subscale (STAI-S) questionnaires, using cutoffs of 16 and 38 indicating high symptoms. Participants were categorized into four outcome groups: (1) no symptoms, (2) high depressive symptoms only, (3) high anxious symptoms only, and (4) comorbid high symptoms. Multinomial regressions were performed. Results: LCA identified three ACE classes: low-risk, family discordance, and multidimensional adversity. Women reporting two or more ACEs had higher odds of depressive and comorbid symptoms, compared to those with zero ACEs. Compared to the low-risk class, women in the family discordance class had increased odds of high depressive symptoms (adjusted odds ratios [aOR] 95% confidence interval [CI] = 1. 80 [1.33, 2.56]) and comorbid high symptoms (aOR [95% CI] = 2. 04 [1.43, 2.89]). Threat experiences were significantly linked to high depressive symptoms (aOR [95% CI] = 1. 48 [1.22, 1.79]) and comorbid high symptoms (aOR [95% CI] = 1. 53 [1.25, 1.87]). Conclusion: Using the DMAP and LCA approaches, we found that ACEs related to the familial environment and relationships during childhood were most strongly associated with prenatal high depressive and comorbid symptoms. This highlights the importance of operationalizing ACEs beyond a cumulative score to better capture their role in the development of prenatal mental health difficulties
A deep learning-assisted hybrid model for electric dosimetry in electroporation therapies
No full textInternational audienceAccurate electric dosimetry is essential for predicting treatment outcomes in Irreversible Electroporation (IRE), a promising non-thermal tumor ablation technique. However, real-time 3D electric field computation remains computationally expensive, limiting its practical use in clinical settings. In this study, we propose a hybrid approach combining deep learning (DL)-based initialization with an iterative numerical solver to accelerate dose map calculation. Specifically, we employ a convolutional neural network (CNN) to predict basis functions, which are subsequently refined using a Biconjugate Gradient Stabilized (Bi-CGSTAB) solver to maintain physical accuracy. We evaluate our method on data from 10 patients undergoing IRE liver ablation under real-time clinical conditions. Our results demonstrate a 10× speedup compared to conventional solvers while maintaining comparable accuracy. This hybrid method offers a promising pathway toward fast and reliable electric dosimetry for on-line IRE procedures
Stable 710kW average-power of infrared-red light stacked in an optical enhancement cavity of finesse 45,000
No full textInternational audienceAdvances in laser technology over the past 25 years have been impressive, in particular for the Ytterbium technology where, nowadays, kilowatt-class laser systems are available. This technology also led to the possibility to provide hundreds of kilowatts of laser power through the use of enhancement cavities. We report here on the demonstration of a stable 710 kW average laser power, obtained in a two-mirror configuration of the optical enhancement cavity, as well as a stable 500 kW average laser power in a four-mirror bow tie high-finesse enhancement cavity. 710 kW is, to the best of our knowledge, the highest intracavity power ever achieved in such cavities with such a high enhancement factor. It sets the stage towards reaching a MW average power in an optimized optical enhancement cavity geometry
Accueilli⋅es comme les autres ? Les exilé⋅es ukrainien⋅nes dans une métropole française
No full textInternational audienceUkrainians have benefited from an unprecedented wave of hospitality in France, driven by the mobilization of institutional actors, associations, and local residents. However, by establishing this exceptional reception framework outside the existing asylum system, the state has emphasized its temporary nature. It has largely delegated its management and coordination to civil society organizations, particularly Ukrainian community networks. A joint investigation conducted in a French metropolis sheds light on the roles and relationships among these various actors in response to the influx of Ukrainian exiles, particularly between February 2022 and June 2023.Les Ukrainien⋅nes ont bénéficié d’un élan d’accueil sans précédent en France, avec la mobilisation d’acteurs institutionnels, associatifs et d’habitant⋅es. Toutefois, en créant cette dynamique d’accueil exceptionnel en marge du système d’asile existant, l’État en a souligné le caractère provisoire. Il en a délégué la gestion et l’animation avant tout aux acteurs associatifs, notamment aux réseaux communautaires ukrainiens. Une enquête à quatre mains dans une métropole française permet d’éclairer les rôles et les relations qu’entretiennent ces différents acteurs à partir de l’afflux des exilés.es ukrainien⋅nes, notamment entre février 2022 et juin 2023
Modèles 3D multi-scalaires, lasergrammétriques et photogrammétriques, de sites ornés du massif de l’Erongo (Namibie, Afrique australe)
No full textInternational audienceLe nord du massif de l’Erongo (Namibie, Afrique australe) présente plusieurs sites ornés de premier ordre, dont l’étude nécessite une mise en contexte géomorphologique. Les granites et granodiorites du Crétacé affleurent sous forme de longues croupes et de chaos de blocs formant des abris dans lesquels se trouve l’art pariétal, ainsi que des séquences d’occupations humaines datant au moins de la fin du Pléistocène. Dans le cadre du projet ANR Cosmo-Art (ANR-21-CE27-0011 ; https://cosmo-art.org/), l’analyse des parois ornées et du contexte des chaos de blocs a motivé le déploiement d’une méthode de relevés 3D rapide et adaptée à ces environnements singuliers. A l’échelle du site (pluri-hectométrique), les relevés sont conduits par photogrammétrie avec un drone Mavic 2 pro. A l’échelle du chaos (pluri-décamétrique), les relevés sont réalisés avec un lidar terrestre Faro Focus 3D. Enfin, à l’échelle de la paroi (pluri-métrique), les relevés sont conduits par photogrammétrie avec un APN plein format. En combinant ces méthodes de numérisation, nous abordons les sites de façon multiscalaire tout en profitant de l’intérêt particulier que chacune apporte : couverture large et référencement simplifié avec le drone, justesse géométrique avec le lidar terrestre, haute résolution avec la photogrammétrie sur paroi. Avec cette approche, un site peut être relevé en une ou deux journées avec deux opérateurs. Plusieurs procédés et plusieurs logiciels d’assemblage et de consolidation sont ensuite testés (Register, Cyclone 3DR, Metashape, Cloud-Compare, Reality Capture…). Quatre sites ont déjà été traités, livrant une documentation homogène pour les analyses archéologiques et les études géomorphologiques : Ekuta, Leopard Cave, Fäckelträger et Seal Rock Shelter