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Organohalogen contaminants of emerging concern in common dolphins (Delphinus delphis) from the Bay of Biscay (NE Atlantic): occurrence and 2000–2023 temporal patterns
No full textInternational audienceThe contamination of marine mammals by legacy pollutants has been largely studied in oceans worldwide. However, international regulations have given rise to the replacement of legacy substances by alternative compounds, which represent a potential additional threat to marine mammal health and conservation. In this study, we investigated the occurrence and temporal trends of contaminants of emerging concern (CECs) in the blubber of common dolphins (Delphinus delphis) from the Bay of Biscay, North-East Atlantic, and in their major prey. Alternative brominated flame retardants were below the limits of quantification in all samples, while dechlorane-related compounds were identified as the major CECs, at levels of 4.6 ± 5.9 ng g -1 lw, i.e. similar to or higher than those reported in various marine mammals from other oceanic regions. The concentrations of 3,6dichlorocarbazole (3,6-CCZ), the major polyhalogenated carbazole, and of methyl-triclosan were one order of magnitude lower. The halogenated natural products, methoxylated polybrominated diphenyl ethers (MeO-BDEs), were also investigated and showed substantially higher concentrations than all CECs, i.e. 322 ± 214 ng g -1 lw. Declorane-602, anti-monohydro dechlorane plus and MeO-BDEs were the only compounds showing biomagnification between small pelagic fish and dolphins. No significant differences in most CEC concentrations were found over the studied time period, indicating that these compounds are still emitted in the environment and/or have long residence times in the dolphins' blubber. Conversely, methyl-triclosan concentrations significantly decreased over the studied period. An increase in MeO-BDE concentrations in the last two decades might reveal a change in algal production in relation to global warming.</div
Defining optimal small woody features and water densities to maximize European turtle-dove (Streptopelia turtur) occurrence in French agricultural landscapes
No full textInternational audienceThe European turtle-dove is globally threatened, suffering a widespread and sustained decline in numbers across its breeding range, partly driven by habitat loss. Although the effects of certain habitat features are recognized, questions remain as to which landscape elements should be given priority and in what proportions. We assess how different habitat elements influence the occurrence density of turtle-dove at two management scales (25 and 100 ha), using fine-scale GPS tracking data from 38 turtle doves in France during the breeding season. We found some non-linear responses, with a steeper increase in occurrence density up to at least 25 % small woody features (SWF) density or 10 % water density at a 100 ha scale, refining the proportion to nearly 50 % for SWF at a 25 ha scale. Additionally, at a 25 ha scale, broadleaved forest displayed a bell-shaped trend, indicating a positive effect up to 22 %, whereas vineyards showed a sharp initial decline at a 100 ha scale. Grassland was positively associated with occurrence at the 100 ha scale, whereas fodder, cereal, and broadleaved forest showed negative effects at the same scale, while fodder, build-up, and maize had negative effects at the 25 ha scale. Variable importance analysis revealed that water was the most influential factor at 100 ha, followed by SWF, while at 25 ha, SWF was dominant, followed by water, highlighting scale-dependent habitat preferences. Our study provides insights into the optimal densities of SWF and water resource required for effective conservation, offering valuable guidance for the management and restoration of turtle-dove breeding habitats in agricultural landscapes
Protection de l'enfance et jeunes en migration : croiser la recherche et l'action
No full textÉquipe pluridisciplinaire en sciences sociales (histoire, sociologie, anthropologie, science politique), le Collectif MINA93 a réalisé une recherche-action en partenariat avec le Conseil Départemental de Seine-Saint-Denis, entre 2019 et 2022, financée par une bourse CNRS de l’Institut Convergence Migrations.International audienceLes mineur·es non accompagnés sont au coeur d'un débat politique et social majeur. Cet ouvrage explore la prise en charge de ces jeunes, prise entre enjeux de contrôle migratoire et protection de l'enfance. Croisant recherches en sciences sociales et témoignages de terrain, il analyse les pratiques des acteurs divers du champ de la protection de l'enfance (services départementaux, justice, associations...), un secteur en pleine mutation face aux évolutions des migrations juvéniles, et aux problématiques de l'accompagnement des jeunesses vers l'autonomie. Collectif MINA93 = Bonnet Doris, Bouagga Yasmine, Destremau Blandine, El Qadim Nora, Long Julien, Zougbédé Emelin
Hidden markers of health: how mercury affects gene expression in developing seabirds
No full textInternational audienceMercury is a globally recognized environmental contaminant that bioaccumulates and biomagnifies in food webs, thereby causing adverse health effects in both humans and wildlife. While mercury exposure is known to impact several life-history traits in birds, the molecular mechanisms underlying these effects remain poorly investigated. In this study, we examined the association between blood mercury concentrations and the expression of 15 key genes involved in detoxification and oxidative stress regulation in magnificent frigatebird Fregata magnificens chicks from French Guiana. Specifically, we measured the expression of genes encoding glutathione-dependent enzymes (GSTA1, GSTA2, GSTK1, GSTM1, GSTT1_0, GSTT1_1, GPX1, GPX2, GPX3, GSS, GSR_0 and GSR_1), thioredoxin system (TXNRD1 and TXNRD3), and metallothionein (MT1). Our results revealed a significant decrease in GSTA1, GSTA2, and GSTT1_1 expression with increasing mercury concentrations. No significant associations were found for glutathione peroxidases, glutathione synthetase and reductases, thioredoxin reductases, or metallothionein expression. These findings might indicate a potential increase in toxicity and cellular damage due to the lower detoxification of glutathione S-transferases. We emphasize the need for further investigations into species-specific mechanisms of detoxification. Our study supports the utility of gene expression analysis in addition to traditional physiological measurements to assess contaminant induced disruptions
La francophonie: de la communauté linguistique et culturelle à l'organisation internationale aux missions élargies
No full textInternational audienc
Quelle acceptabilité sociale des navettes autonomes ? La réponse ambivalente des consommateurs
No full textInternational audienceThe social acceptability of autonomous shuttles evokes a range of emotions among consumers, notably ambivalent emotions oscillating between technological interest and fear of the device. This study analyzes these anticipated emotions and the coping strategies consumers use to manage these conflicting feelings. Relying on a qualitative approach based on 18 semi-structured interviews with potential users of on-demand shuttle services, this research identifies consumers’ anticipated emotions. The findings categorize these emotions and link them to corresponding coping strategies. This study contributes to a better understanding of emotions in a new urban mobility context and offers recommendations to improve the integration of autonomous shuttles into society.Quelle acceptabilité sociale des navettes autonomes ? La réponse ambivalente des consommateurs Résumé : L'acceptabilité sociale des navettes autonomes soulève des émotions chez les consommateurs, notamment des émotions ambivalentes oscillant entre intérêt technologique et peur du dispositif. Ce travail propose une analyse de ces émotions anticipées et des stratégies de coping mobilisées par les consommateurs pour gérer ces émotions conflictuelles. S'appuyant sur une approche qualitative basée sur 18 entretiens semi-directifs auprès d'usagers potentiels de navettes de transport à la demande, cette recherche identifie les émotions anticipées des consommateurs. Les résultats permettent de catégoriser les émotions et de les mettre en parallèle avec les stratégies de coping. Cette étude contribue à une meilleure compréhension des émotions dans un nouveau contexte de mobilité urbaine et propose des recommandations pour améliorer l'intégration de navettes autonomes dans la société
AI4RDD: Artificial Intelligence and Rare Disease Diagnosis: A proposal to improve the anamnesis process
No full textInternational audienc
