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Textile fonctionnalisé par des cages métallo-organiques pour la capture et la dégradation d'agents de guerre chimique
No full textInternational audienceFor more than ten years, the world has seen a resurgence in the number of armed conflicts and an increase in terrorist risks.[1] This threat is reflected in particular by the use of old and new generation chemical weapons. Among these chemical warfare agents (CWA) used are nerve agents (Sarin gas), blisters (Yperite), or suffocants (phosgene). Civilian or military personal protective equipment (PPE) developed to date generally offers passive protection (capture). A transition to active protection (degradation) is particularly interesting, especially if it provides improved protection while maintaining comfort, lightness, washability, mechanical characteristics, IR stealth, and fire protection. Farah has pioneered this field of research by integrating MOFs onto textile composites for the degradation of CWA.[2] This research aims to develop a textile functionalized by Zr-based metal organic cages (MOCs) capable of capturing and degrading model toxic agents of the NRBC type. This very recent class of materials has many advantages (compared to zeolites, activated carbons, and MOFs), particularly due to their solubility.[3] However, several scientific challenges remain in particular regarding the integration of MOCs into textiles as no studies have explored their deposition on textile fibers. Their nanoparticle nature (10⁻⁹ m) should simplify this integration compared to conventional porous materials (MOFs, zeolites). Another improvement is necessary to enhance the strength of functionalized textiles. Unlike microparticulate materials (10⁻⁶ m), nanoscale MOCs could offer better abrasion resistance. Here we demonstrated that the solubility of Zr-based MOC ensure (i) their efficient deposition on textile fiber by a one pot synthesis method, by impregnation or by spray dryer technique (Figure 1), (ii) the capture and degradation of model toxic agents, and (iii) the excellent compatibility with natural textile fibers tested. The resistance (mechanical and aging) of the functional textile was evaluated by aging studies, to obtain a fiber maintaining its degradation capacities under rigorous conditions (UV, H2O, temperature, abrasion, perspiration, etc.). This compromise between efficiency and textile properties leads us closer to active protection for PPE
La standardisation des cours collectifs de fitness Les Mills. Le corps socialisé comme outil de management.
No full textInternational audienceDans le paysage des pratiques de fitness, Les Mills s'impose par la standardisation de ses cours collectifs, révélant une approche unique de management "par corps". Ce chapitre explore comment les pratiques de fitness Les Mills, en s'appuyant sur des chorégraphies strictement normées, utilisent le corps comme levier social et managérial.À travers une organisation hiérarchisée, où l'ascension sociale se mêle à l'engagement physique intense, Les Mills façonne un microcosme où le corps devient un capital central. Les instructeurs intègrent une technique corporelle rigoureuse, évoluant au sein d'un environnement où l'apparence physique et la maîtrise des mouvements sont des indicateurs clés de succès.Ces dynamiques soulignent une socialisation "par corps" comme méthode de gestion, intégrant des apprentissages qui vont au-delà de l'exercice physique pour influencer profondément les comportements et l'identité des instructeurs. Ce modèle propose ainsi une approche innovante et implicite de la gestion des ressources humaines.Dans la quête de performance et de visibilité, l'étude met en lumière comment Les Mills transforme le corps en vecteur d'identité culturelle et professionnelle, questionnant la pérennité de telles méthodes face aux exigences d'innovation du marché du fitness
CREATION D’UNE FERME URBAINE SUR UNE FRICHE INDUSTRIELLE: Apport de différents composts sur les fonctionnalités du sol et le devenir des polluants
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P1273 High Crohn's Disease incidence associated with multiple heavy metal contamination in agricultural soils: findings from the CROPS project in Northern France
No full textInternational audienceBackground Crohn's Disease (CD) is a chronic intestinal disease with an unclear etiology and suspected environmental risk factors. The CROPS (CROhn’s disease and Pollution of Soils) project was initiated in Northern France to investigate links between the high incidence of CD and environmental pollutants. In this context, we combined data of a population-based registry of Inflammatory Bowel Disease (IBD) with environmental sampling data to identify the environmental profile of multi-contamination associated with high incidence. Methods This ecological study was conducted at the municipal level within the coverage area of the registry in Northern France. All patients diagnosed between 2000 and 2017 were included (n=9,019). Spatial clusters of significantly high (n=4) and low (n=4) CD incidence, adjusted for age and sex, were identified based on patients' residence addresses at diagnosis. Within these clusters, environmental sampling was performed across 240 sites using a hexagonal grid to ensure 30 samples per cluster. A total of 490 parameters were analyzed: 306 in soil (including emerging pollutants such as hormones and antibiotics, polycyclic aromatic hydrocarbons [PAHs], heavy metals, and pesticides), 152 in tap water (examining heavy metals and PAHs), and 30 in lichens (assessing heavy metals as indicators of air quality). Multi-contamination indices, such as the Mean Impregnation Ratio (MIR) and Pollution Index, were applied. Data analysis included Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), and Analysis of Variance (ANOVA) tests. Results High-incidence clusters, predominantly agricultural, had elevated heavy metal concentrations in soil (notably chromium, arsenic, zinc, and nickel), sulfadiazine in soils, high nitrate levels in water, and heavy metals in lichens. Low-incidence clusters, with greater urbanization, showed elevated PAHs in soil, heavy metals in water, and BPA in soils. Pollution profiles aligned with different land covers, with significant findings for agricultural lands (p<0.0001). A positive correlation between the relative risk and soil’s MIR for heavy metals in agricultural zones was noted (r=0.557, p=0.005). Conclusion These findings suggest a possible link between high CD incidence and heavy metal exposure in agricultural lands. Profiles of pollution were created for each cluster. Future studies should expand on pesticide and agricultural pollutant analysis to strengthen this hypothesis, and consider individual-level epidemiological approaches to further elucidate these potential environmental risk factors
P1272 Spatio-temporal distribution of IBD incidence at a territorial level in northern France using the EPIMAD registry (2000-2017): analysis of environmental determinants suggests influence of agricultural practices.
No full textInternational audienceBackground Crohn’s disease (CD) and ulcerative colitis (UC) are chronic inflammatory bowel diseases (IBDs) with complex and multifactorial etiologies. Genetic factors have been identified but cannot fully account for disease incidence. Spatial heterogeneity in IBD incidence has been reported across various countries and scales, suggesting a significant influence of environmental factors. Leveraging the population-based EPIMAD registry in northern France (6 million inhabitants), this study aimed to analyze the spatial distribution of CD and UC incidence and identify potential environmental risk factors at a territorial level. Methods This ecological study was conducted at the municipal level across 3,041 municipalities within the EPIMAD registry's area for the period 2000-2017. Incident cases included 9,019 CD and 5,789 UC patients. Spatio-temporal age- and sex-standardized incidence ratios were modeled using Bayesian hierarchical models. An inventory of open-access environmental data sources identified 128 datasets, 19 of which were selected to generate 112 indicators at the municipal level. These indicators included contamination levels (air, water, soil), proximity to emission sources (e.g., industrial sites), land use, agricultural practices, natural features, and climate. Ecological regressions were used to explore associations between environmental indicators and incidence. Results Significant spatial disparities in CD and UC incidence were observed, remaining stable over time (Figure 1). For both CD and UC, associations were found with certain types of crops (e.g., sugar beets, barley, wheat, flax, and potatoes) and several metals in soil (e.g., molybdenum, nickel). Associations were more pronounced for CD, including strong links with pesticide use indicators (growth regulators, herbicides, fungicides) and soil contamination by other metals such as arsenic, cadmium, and thallium. For UC, a unique association was observed with soil contamination by polycyclic aromatic hydrocarbons (PAHs), while no significant association with pesticide use was found. Conclusion These findings highlight a relationship between IBD incidence and agricultural practices, providing new insights to the existing literature. Multivariate approaches should be employed to better describe environmental exposure profiles. Additionally, individual-level epidemiological studies are needed to confirm and expand upon these results
Dietary proteins from various sources have different effects on short-term food intake and intestinal hormone secretion
No full textInternational audienceBesides their nutritional role, proteins are recognized for their ability to regulate both short- and long-term energy homeostasis. However, studies investigating the effects of proteins based on their quality and origin remain limited and often lack comparability. Nonetheless, existing research consistently underscores the influence of proteins on food intake regulation. Additionally, digested proteins promote satiety by stimulating the secretion of intestinal hormones. This study aimed to compare the effects of proteins from different origins (hemoglobin, caseins, ovalbumin, whey proteins, fish gelatin, pea proteins and gluten proteins) on short-term food intake using Wistar rats in metabolic cages. Proteins were then digested using in vitro static INFOGEST protocol to assess their effects on intestinal hormone secretion using STC-1 cells. The results revealed distinct impacts of these proteins on short-term food intake, respiratory exchange ratio, but also on GLP-1 and CCK secretion. This study demonstrates the impact of various proteins on energy homeostasis by affecting the regulation of short-term food intake, which correlates with the modulation of intestinal hormone secretion. The findings also emphasize the role of protein origin in these mechanisms, with whey, pea, and gluten emerging as the most effective. Differences in satiety among proteins can be attributed to variations in digestibility rates and effects on intestinal hormone secretion, indicating that dietary proteins regulate food intake in a manner dependent on both their nature and origin
Electrical Performance analysis of Enamelled-Extruded Wires based on Partial Discharges and Voltage Endurance
No full textInternational audienceThis study aims to explore an economically feasible enamelled wire technology based on sol-gel, offering enhanced performance compared to traditional enamelled wire. The evaluation involves assessing insulation configurations for copper wires designed for high-temperature applications, with a proposed configuration combining sol-gel solution on enamel and PPS extrusion resins. Electrical performance is compared across these insulation configurations, building upon their demonstrated higher thermal performance in prior research. Experimental data, including partial discharge parameters, dielectric strength, and electrical aging endurance, are collected from twisted pair samples for each insulation type. Promising results emerge from partial discharge studies, favoring hybrid technology (enamelled-extruded wires) over the classical approach (PEI+PAI enamelled wires). Measurements reveal a higher intensity of partial discharges for classical enamelled wires under 3 kV-50 Hz. Moreover, lifespan models under voltage stress indicate that enamelled-extruded wires with PPS extruded resin have advantages, withstanding 1525 minutes compared to 530 minutes for classical wires under 3 kV-50 Hz. A correlation between lifespan under voltage stress and partial discharge intensity is observed. Furthermore, microfillers on PPS show lower results compared to non-filled enamelled-extruded wire configurations
CFD analysis of fine clay particles dispersion from a truck operating on unpaved roads
No full textInternational audienceHeavy trucks are a major source of particle resuspension when moving on unpaved sites. The forces exerted by truck wheels on the soil lead to particle detachment and massive particle entrainment, forming dust clouds dispersion in the vehicle’s wake. To mitigate these emissions, understanding and characterizing the flow downstream earthworks dump trucks is crucial. In this study, we present an advanced Euler–Lagrange Computational Fluid Dynamics (CFD) investigation of an air flow developed in the wake of a reduced scale (1:50) simplified model of a Mercedes 8 × 4 dump truck. The paper explores the fluid flow behavior induced by three different types of truck loads: empty, full and overloaded truck beds. Solutions for mitigating dust resuspension are investigated by exploring the influence of the attachment of single and double mudflaps compared to a reference case without mudflaps. Comparing the CFD results to experimental wind tunnel measurement data, reveals the validation and accuracy of the present 3D CFD model. 40000 particles of dry clay, in diameter and of density 1600 kg/ are then injected to mimic the truck passage over a dusty ground, similar to truck movement on a construction site. This allowed to investigate the particles entrainment and resuspension phenomena in the wake region downstream the truck. The present findings contribute to a better understanding of the wake flow dynamics and particles entrainment and resuspension behind earthworks dump trucks, highlighting the importance of flow control to mitigate dust particles air pollution
Enhancing the electronic and photocatalytic properties of (SnO 2 ) n /(TiO 2 ) m oxide superlattices for efficient hydrogen production: a first-principles study
No full textInternational audienceDFT calculations reveal that strain engineering in (SnO 2 ) n /(TiO 2 ) m superlattices provides a promising strategy to enhance photocatalytic properties, particularly for hydrogen production via water splitting
Cyclodextrin-based formulations for delivering broad-spectrum nerve agent antidote to the central nervous system: stability, physicochemical characterization and application in a human blood–brain barrier model
No full textInternational audienceNerve agents, such as VX and sarin, represent a significant threat to global security due to their devastating neurotoxic effects and potential for misuse. The therapeutic inefficacy of current countermeasures underscores the urgent need for more effective alternatives. In this context, recent advances have identified JDS364.HCl, an uncharged hybrid antidote, as a promising candidate. However, its instability in aqueous solution remains a significant challenge. To address this, cyclodextrin-based formulations were developed using two EMA-approved cyclodextrins: HP-β-CD and SBE-β-CD. These formulations significantly improved JDS364.HCl stability for over two months at room temperature. Interaction studies revealed a 1:1 stoichiometry for both cyclodextrin complexes, with JDS364.HCl: SBE-β-CD exhibiting a 100-fold higher affinity constant, attributed to additional electrostatic interactions with SBE-β-CD sidechains. While SBE-β-CD provided superior plasma stability compared to HP-β-CD, the high binding affinity of JDS364.HCl: SBE-β-CD complexes hindered the molecule's release and reduced its ability to cross the BBB, as observed in a human BBB model. Nonetheless, the results for both cyclodextrins are encouraging, as they enhance JDS364.HCl's stability in plasma while allowing its passage across the BBB. Notably, JDS364.HCl demonstrated superior BBB permeability compared to marketed antidotes such as 2-PAM. These findings highlight the potential of cyclodextrins to improve the efficacy of JDS364.HCl as a nerve agent antidote.</div