Portail HAL UA (Université d'Angers)
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Première réunion du groupe REcherche sur la Santé des Sapeurs-pompiers et autres professionnels de la Sécurité Civile en urgence (RE3SC), ministère de l’Intérieur, Paris 29 avril 2025
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In situ electrochemical synthesis of rhenium oxide-reduced graphene oxide hybrid electrodes for enhanced water splitting
No full textInternational audienceThis study reports the in situ electrochemical synthesis of rhenium oxide nanoparticles on a glassy carbon (GC) electrode pre-modified with graphene oxide (GO), which is simultaneously reduced to reduced graphene oxide (rGO) during deposition. The resulting GC|rGO|ReOxNP electrodes were characterized by XPS, SEM, TEM, and EDS. Optimal HER performance was obtained with a 60 s deposition, achieving an overpotential of -0.160 V at 10 mA cm- 2 and a Tafel slope of 52 mV & sdot;dec- 1. The post-HER analysis showed that the optimum electrocatalytic properties were associated with the predominant rhenium oxidation states ReVI and ReVII. A key strength of this approach lies in its simplicity and sustainability: the electrochemical method provides a direct, single-step route for simultaneously depositing rhenium oxide nanoparticles and reducing GO to rGO under mild conditions. This eliminates the need for high-temperature treatments or multistep chemical procedures commonly reported in similar studies. These results highlight the potential of ReOxNP|rGO hybrid electrodes as efficient and scalable HER catalysts for green hydrogen production
L'essence poétique de l'impression ou "L'art mnémonique" de Charles Baudelaire
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Multiple maternal occupational exposures during pregnancy and intrauterine growth: analysis of the French Longitudinal Study of Children - ELFE cohort, using data-driven approaches
No full textInternational audienceObjective: To use data-driven approaches to investigate maternal multi-occupational exposures during pregnancy and their effects on intrauterine growth.Methods: Maternal occupational exposure to 47 factors during pregnancy was evaluated with job-exposure matrices in the French ELFE cohort. The outcomes of interest were birthweight (BW), small for gestational age (SGA) and head circumference (HC). Occupational exposures associated with these outcomes were identified by EWAS, LASSO, and random forest. The five exposures with the strongest effects selected with these approaches were included in a final multivariate model with significant interactions.Results: We included 12,851 women. The most important occupational factors predictive of SGA were endocrine disruptors, high strain, kneeling/squatting, job demands, physical effort. No significant associations were detected when these variables were combined in a final model. For BW, the most important variables were leaning forward/sideways, using a computer screen, ultrafine particles, physical effort, airborne germs, repetitive actions. The use of a computer screen significantly decreased BW and, for women not exposed to airborne germs, leaning forward/sideways significantly increased BW. For HC, repetitive actions, oxygenated solvents, kneeling/squatting, airborne germs, working outdoors were the most important predictive factors. Repetitive actions and working outdoors significantly decreased HC. HC also decreased in women exposed to both airborne germs, and oxygenated solvents. Similar results were found for women who worked during the third trimester.Conclusion: Our findings highlight potential roles of chemical, biological and postural factors and their interactions in determining intrauterine growth. These results highlight the importance of considering multiple exposures in occupational health studies
Exploring boundary conditions of physical activity maintenance: A secondary analysis of time-series data from a weight-loss intervention
No full textInternational audienceObjective: A key concept in health psychology is behavioral maintenance. However, previous research has struggled to establish shared conceptualizations and operational definitions. This study aimed to contribute to this debate by examining whether a simple conceptual proposition of physical activity maintenance as ‘the performance of physical activity according to an intended target threshold over a specific period of observation’ can be empirically supported, and under which boundary conditions. Specifically, we explored different formulations of two boundary conditions: activity threshold and timescale of change.Methods: We analyzed 350 time series (length = 182 days) of moderate-to-vigorous physical activity (MVPA) collected daily with Fitbit from participants in a weight loss intervention. All participants reported an intention to engage in at least 150 min of MVPA per week over the following six months. Activity thresholds were defined based on each participant’s baseline MVPA. Generalized Additive Models were used to model individual trajectories across varying timescales (7, 14, 28, and 56 days).Results: At short timescales (7–14 days) trajectories crossed the threshold frequently, indicating high variability. At longer timescales (28–56 days) trajectories were more stable, with participants tending to stay either above or below their threshold, aligning with our target conceptualization of maintenance. Relaxing the threshold by 10–20% relatively increased the proportion of participants classified as maintainers, though maintenance remained uncommon for participants with higher thresholds.Conclusions: Our findings provide initial evidence on which boundary conditions support detecting physical activity maintenance as conceptually defined. These results underscore the importance of systematically testing boundary conditions to advance understanding of behavioral maintenance
Le tourisme vecteur de développement durable en Indonésie ?
No full textInternational audienceLe tourisme a été perçu depuis la fin du XIXe siècle, comme un vecteur de développement en Indonésie. La première mise en tourisme de Java et Bali résultait d’un projet politique colonial, destiné à en offrir une image exotique et policée, tentant d’effacer la brutalité de leur « pacification ». Les présidents Suharto puis Sukarno, de la jeune République Indonésienne, proclamée en 1945, accordent aussi de l’importance à la valorisation économique apportée par le tourisme domestique, puis international, stimulé à partir de la fin des années 1960, par la création de vastes infrastructures, notamment à Bali. Rapidement conscients des limites de l’essor des grandes stations internationales, largement aux mains d’investisseurs étrangers, les autorités s’intéressent, dès 1989, aux enjeux de soutenabilité, en créant le Bali Sustainable Development Project (BSDP). Ce projet aboutit en 1992 au programme des desa wisata (villages touristiques), qui deviendra un label national. Combinant les standards internationaux de la qualité d’accueil, la poursuite d’activité rurale traditionnelle et des préoccupations environnementales, il a pour dessein de créer un modèle de développement touristique durable adapté aux villages indonésiens, qui rencontre un vif succès : aujourd’hui 1200 villages sont labélisés, mais favorise-t-elle réellement un développement durable des territoires dans leur diversité
Découverte de nouveaux algorithmes de recherche locale par neuro-évolution
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Determinants and consequences of climate commitment among facilitators of environmental awareness workshops: A Mixed-Methods Exploratory Study
No full textProtocoleClimate activism is an expanding form of civic engagement in response to the ecological crisis. Among these initiatives, the facilitation of participatory environmental workshops (e.g., climate, biodiversity, oceans, food systems, digital sustainability) has emerged as a structured and accessible way to disseminate knowledge, foster collective awareness, and promote pro-environmental behavior. In France alone, more than 150 different workshop formats exist, involving thousands of volunteer and professional facilitators. However, little is known about the psychosocial determinants of such engagement, nor about its behavioral and psychological consequences for facilitators themselves. This study aims to explore 1) the determinants of sustained engagement as a facilitator of environmental awareness workshops, and 2) the associated outcomes in terms of pro-environmental behaviors and climate-related emotions.Methods. This cross-sectional mixed-methods study will include (a) an online survey distributed to facilitators of environmental awareness workshops across France, with the objective of reaching at least 500 respondents, and (b) semi-structured interviews with a subsample of approximately 30 participants. The quantitative component will assess multiple dimensions of facilitation engagement, pro-environmental behaviors (mitigation, adaptation, and collective action), climate-related emotions (including eco-anxiety, hope, and helplessness), as well as psychosocial variables such as ecological identity, selfand collective efficacy, sense of community, and political orientation. The qualitative component will provide in-depth insights into facilitatorsʼ motivations, perceived barriers, and subjective experiences of the personal and collective impact of their involvement.Expected Results. The study will generate a multidimensional profile of facilitator engagement and identify key psychosocial predictors of sustained involvement. It will also document potential behavioral and psychological outcomes of facilitation, thereby informing strategies to better support, recognize, and sustain volunteer-driven environmental engagement.</p