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Sterile insect technique for suppression of endemic Aedes albopictus in urban Reunion Island: a pilot trial of technical feasibility and entomological impact
No full textInternational audienceBackground. The sterile insect technique (SIT) has progressed from theory to a validated vector control strategy for Aedes-borne diseases, including dengue and chikungunya. We assessed the feasibility and effectiveness of SIT for suppressing Aedes albopictus in small-scale urban environments on Reunion Island.Methods. From July 2021 to September 2022, over 10 million Ae. albopictus males sterilised as pupae with 40 Gy X-rays were released at a 20-hectare pilot site. Weekly releases ranged from 60,000 to 275,000 males (3000–13,750 per hectare). Outcomes were monitored using ovitrap surveillance and periodic adult sampling during a 6-month baseline and a 13-month intervention.Results. Sterile-to-wild male ratios ranged from 6:1 to 18:1. Compared with the control site, the treated site showed a 33.5% reduction in egg abundance and a 61.5% reduction in egg viability (range 40.0–81.9). Reductions in egg fertility were temporally aligned with a 60.4% decline in female abundance relative to baseline.Conclusion. This study demonstrates that SIT was technically and logistically feasible and achieved measurable suppression of Ae. albopictus. Despite scale and operational constraints, the intervention achieved significant reductions in egg fertility and female abundance, providing strong proof of concept for SIT-based mosquito control on Reunion Island
Les radios locales peuvent-elles contribuer à la surveillance épidémiologique ?
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616762/) * Autres projets (id;sigle;titre): ;TSARA;(FRA) Transformer les systèmes alimentaires et l'agriculture par la recherche en partenariat avec l'Afrique//International audienc
Impacts of Nearby Algae on Recruitment Success and Early Microbiome Development of the Coral Acropora cytherea
No full textInternational audienceThe persistence of coral reefs is dependent on the arrival and settlement of coral larvae followed by their post‐settlement growth and survival. Despite evidence showing that benthic algae have variable effects on corals, it is still unclear how benthic communities of the coral nursery habitat impact the early development of the coral microbiome and if these impacts relate to the survival and growth of newly settled corals. Here, we tested whether the survival and growth of Acropora cytherea recruits are impacted by surrounding algae, and whether specific algae influence their associated bacterial and Symbiodiniaceae communities. A 6‐month survey of coral larvae experimentally settled near different algae showed that crustose coralline algae enhanced recruit survival. However, despite variation in their microbiome, the presence of different algae did not impact the coral microbial community composition. The recruit microbiome was colonised by bacteria shared among all benthic substrates rather than bacteria unique to specific algae. Furthermore, the microbiome of coral larvae was different from that of the recruits. We conclude that the microbiome of corals in their early life stages is structured by host ontogeny rather than by their surrounding benthos, but that the surrounding benthos contributes to the transfer of opportunistic bacteria
Lithium Isotopic Composition of Fluid Inclusions provides insights into Fluid–Rock Interaction in Subducted Sediments and Sources of Mud Volcano Fluids
No full textInternational audienceLithium isotopes have been widely used to investigate fluid-mediated processes in subduction.However, direct analysis of pore fluids in metamorphic rocks remains challenging due to prohibitive depths at which these processes occur. To evaluate the potential of Li concentration and isotopic composition recorded in fluid inclusions, we employed a crush-leach technique to +9.5‰), and Shimanto (+2.5‰ to +10.4‰) is primarily governed by the presence of Li-bearing mineral phases during vein formation-particularly chlorite, white mica, and paragonite-and their capacity to retain lithium. In closed systems, δ 7 Li values of pore fluids can be explained by Rayleigh fractionation during the crystallization of chlorite, illite/phengite, and paragonite, which dominantly incorporate 6 Li, leaving the fluids enriched in 7 Li and therefore having heavier δ 7 Li values. Conversely, in open systems, continuous Li removal from the rocks results in decreasing δ 7 Li values of pore fluids, though their Li concentrations remain comparable to those in closed systems. Similarities in Li concentrations and δ 7 Li values between leachates and mud volcano fluids in modern examples of subduction zone forearcs further confirm that such fluids dominantly originate from subducted sediments. Collectively, this study demonstrates the capability of Li isotope systematics of fluid inclusions to effectively contribute to the understanding of fluid-rock interactions in subducted lithologies.</div
Thiamine and folate immunolocalization in germinating lentil seeds: A microstructural investigation
No full textInternational audienceHighlights: • Thiamine and folate act as cofactors in many human and vegetal metabolic pathways. • Germination is an effective process for increasing the thiamine and folate content. • Immunohistochemistry can localize the storage area of thiamine and folate. • Image analysis revealed heterogeneous distribution of vitamers in the pulse. • We obtained both quantitative and qualitative information on the metabolite content.Abstract: Thiamine and folate are vital for both human and plant health, serving as cofactors in various metabolic processes. Thiamine is essential for carbohydrate and amino acid metabolism, while folate is crucial for DNA synthesis and the methyl cycle. Germination has been proven to increase thiamine and folate levels in lentils. While high-performance liquid chromatography (HPLC) is effective for measuring vitamin content, it does not reveal the spatial distribution of these compounds within seeds during germination. To address this, immunohistochemistry (IHC) was used in this study to localize and quantify thiamine and folate in dry, soaked, and germinated lentils. The analysis revealed that these vitamins are distributed unevenly across cotyledons and cells. In dry seeds, thiamine and folate were concentrated around starch granules, but in soaked and germinated seeds, they were dispersed throughout the cytoplasm and near protein bodies. This innovative method provided both quantitative and qualitative insights into how germination affects vitamin distribution, enhancing our understanding of seed metabolism and the behavior of vitamins during food processing
Climate change demands coordinated adaptation strategies of drinking water treatment
No full textInternational audienceClimate change is tightening its grip on the world’s drinking water, threatening both safety and supply. Without urgent and coordinated adaptation of treatment systems, this overlooked vulnerability could compromise global water securit
Evaluation of pectin and fiber in Cambodian mango peel and pulp from young to ripe maturity stages - a tool for industry
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616285/) * Autres projets (id;sigle;titre): ;SWM Programme;(EU) Sustainable Wildlife Management Programme//International audienceIn tropical countries, the mango sector generates high volumes of byproducts (peel, seeds, rejects, etc.) that need to be valorized. This research carried out on Cambodian Keo Romeat mango waste, was undertaken to support the mango industry. The aim was to better understand how ripening stage and processing method impact the final quality of the products, e.g., animal feed, especially as regards to soluble pectin and fiber content. Mangoes were selected from four ripening stages from young (i.e., green) to over-ripe mango, and processed using blanching and drying, drying or freeze-drying. The characterization of macronutrient (pectin, fiber, ash, lipid, carbohydrate and moisture) content was achieved in pulp and peel for each ripening stage and process treatment. Results showed that both processing and ripening had a significant impact on fiber and soluble pectin content even if ripening always had a greater effect. Maximizing both pectin and fiber contents in the mango pulp or peel was not possible, since the anti-correlation between their concentrations during ripening presented an R² of >0.7. Indeed, when fiber content decreased, the pectin content increased in mango peel and pulp. A simple 4-dimensional data representation was helpful for industrial growers and processors, enabling them to make suitable and appropriate choices between ripening and the processing needs according to the desired product quality without requiring specialized knowledge in food science
Et si l'École de la réussite pour tous passait par la prise en compte du plurilinguisme des apprenants ? Réflexions en appui du projet PEP (Promotion de l'Éducation Plurilingue)
No full textInternational audienc
Introduction. Les sports d'hiver au révélateur de l'Olympisme
No full textInternational audienceCe chapitre introductif propose de tracer minutieusement l’évolution historique des Jeux olympiques d’hiver. Il explore le contexte et les conditions de leur avènement, les dynamiques institutionnelles qui s’y jouent, les mutations de leurs programmes successifs, les méandres géopolitiques dans lesquels ils se meuvent et les résistances auxquels ils font face. En somme, si les Jeux olympiques d’hiver sont un évènement majeur du calendrier sportif international, ils sont tout sauf un « allant de soi » comparé à leurs homologues estivaux
Actes du 7e Colloque international du RAIFFET à l'IPNETP d’Abidjan (CÔTE D’IVOIRE) en 2025: Éducation technologique, formation professionnelle et l’éducation pour une société durable
No full textInternational audienceThis seventh symposium will provide an opportunity to compare perspectives on the issue of education for a sustainable society, from preschool to university, including Technical and Vocational Education and Training (TVET) and non-formal education. We will therefore examine how the objectives for sustainable education are constructed along three axes:Axis 1 — Educational Policies for a Sustainable SocietyThis first axis examines the impact of educational policies on the organization of education and training systems across all sub-sectors of education, particularly in the fields of science, technology, and vocational education.Axis 2: Teaching and Learning for a Sustainable SocietyThis second axis examines the organizational conditions of teaching situations that can foster the acquisition of knowledge and skills by children, adolescents, and adults across all sub-sectors of education, particularly in the fields of science, technology, and vocational education.Axis 3: Information and Communication Technologies for a Sustainable SocietyThis third axis examines the role of Information and Communication Technologies, including Artificial Intelligence (AI), in the teaching and learning process across all sub-sectors of education, particularly in the fields of science, technology and vocational education.Ce septième colloque sera l’occasion de confronter les points de vue sur cette question de l’éducation pour une société durable du préscolaire à l’université incluant l’Enseignement et la Formation Techniques et Professionnelles (EFTP) et l’éducation non formelle. Il s’agit donc de nous interroger sur la manière dont les objectifs pour une éducation durable sont construits selon 3 axes : Axe 1 — Politiques éducatives pour une société durable Ce premier axe interroge l’impact des politiques éducatives sur l’organisation des systèmes d’éducation et de formation dans l’ensemble des sous-secteurs d’éducation, tout particulièrement dans les domaines de l’éducation scientifique, technologique et professionnelle. Axe 2 : Enseigner - apprendre pour une société durable Ce deuxième axe interroge les conditions d’organisation des situations d’enseignement susceptibles de favoriser l’appropriation de connaissances ou de compétences, par les enfants, les adolescents ou les adultes, dans l’ensemble des sous-secteurs d’éducation, tout particulièrement dans les domaines de l’éducation scientifique, technologique et professionnelle. Axe 3 : Technologies de l’information et de la communication pour une société durable Ce troisième axe interroge le rôle des Technologies de l’Information et de la Communication, y compris l'Intelligence Artificielle (IA), dans le processus d’enseignement apprentissage dans l’ensemble des sous-secteurs d’éducation, tout particulièrement dans les domaines de l’éducation scientifique, technologique et professionnelle