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Fading on the beach: pigmentation plasticity adjusts coloration to substrate type in coastal Western spadefoot toads
No full textInternational audienceAnimal species exhibit a wide range of coloration and patterns, which are under strong selection and often linked to individual quality, influencing mate choice, recognition, signaling, and interspecific interactions such as predator avoidance. In amphibians, coloration can vary based on individual traits as well as environmental conditions, including the coloration of their environment. In this study, we described the dorsal coloration (body coloration reticulated by dark patches) in 676 Western spadefoot toads (Pelobates cultripes) from the French Atlantic coast, comparing color variations across different substrates. In addition, we assessed color change in 18 toads transferred between bright and dark substrates. We demonstrated that the dorsal coloration varies based on capture locations (beach vs. inland) and associated substrate types (bright vs. dark), suggesting background color matching. We showed more pronounced effects in females, which might reflect varying predation risks. Experimentally, we showed that individuals can rapidly adjust their coloration to match the substrate within 24 h. Rapid color changes in response to substrate type indicate significant pigmentation plasticity. Bright individuals from sandy substrates showed less dorsal background (body) color change than dark inland individuals, while patch coloration responded differently depending on the substrate of origin. These findings highlight the complex interactions between substrate type, sex, and pigmentation plasticity. These interactions have potential costs and benefits, which might be linked to melanin production, which warrant further investigation
Automated generation of urban weather files for building energy simulation.
No full textInternational audienceThe urban heat island effect significantly impacts building energy demand, particularly for buildings with poor energy performance during the cooling period. To simulate more realistic microclimate conditions, various platforms have been developed, ranging from explicit 3D models to parameterized microclimate models. The latter, requiring fewer input parameters and shorter execution times, is often preferred for building energy studies.A prominent example of a parameterized urban microclimate model is the Urban Weather Generator (UWG) (Bueno, 2013). This simplified multi-model, grounded in energy conservation principles, estimates hourly urban canopy air temperature and humidity using weather data from rural stations. The UWG comprises four modules: a rural station and a vertical diffusion model that compute heat fluxes and vertical profiles at rural sites; an urban boundary layer (UBL) model that estimates the above-canyon air temperature, and a representative Building Energy Simulation (BES)-street canyon model that calculates sensible and latent heat fluxes for both the urban canopy and buildings.In the current literature, the Urban Multi-scale Environmental Predictor (UMEP) QGIS plugin is commonly used to generate import files for UWG. However, this approach necessitates a wide array of GIS data, which can be challenging to obtain, and relies on DOE building archetypes tailored to the U.S. building stock. Additionally, the simulation domain is restricted to a limited number of grids.To address these limitations, this paper introduces the UWG-Connector, an automated tool designed to process high and very high-resolution GIS data at the national scale while enabling parallelized UWG simulations. Furthermore, it presents a methodology for generating building archetypes representative of the French building stock, leveraging detailed data from the National Database of Buildings (BDNB). The model is implemented using Python v3.11 and PostgreSQL v16
Asian Megadeltas: Tackling Coastal Flooding Challenges: Integrating scientific insights into current actions is crucial for steering future research directions and underpinning informed management of coastal flooding in Asian deltas.
No full textInternational audienceAsian megadeltas, including the Ganges-Brahmaputra-Meghna, Irrawaddy, Chao Phraya, Mekong, and Red River deltas, are home to millions of people and are vital for regional food security. However, these regions face escalating risks from sea-level rise, urbanization, socio-economic development, and climate change.A new article in Reviews of Geophysics delves into the intricate dynamics of coastal flooding in Asia’s largest river deltas, highlighting the interplay between local and global changes. Here, we asked the lead authors to give an overview of these Asian megadeltas, the recent scientific advances in understanding coastal flood risks, and the persistent challenges that remain
Evolution of Dried Food Texturization: A Critical Review of Technologies and Their Impact on Organoleptic and Nutritional Properties
No full textInternational audienceThe evolution of food texturization techniques has opened new possibilities for producing healthy, ready-to-eat (RTE) snacks with improved sensory and nutritional properties. Originating from traditional methods such as deep frying and popping, the field has now embraced advanced technologies, including mechanical extrusion, puffing, Détente Instantanée Contrôlée (DIC), and the more recent Intensification of Vaporization by Decompression to the Vacuum (IVDV). These methods focus on enhancing texture and flavor and preserving nutritional value, while also prolonging shelf life, effectively meeting the increasing consumer demand for healthier snack options. This review explores the various food texturization methods, highlighting the key parameters for the optimization of organoleptic and nutritional properties. The strengths and limitations of each method were systematically evaluated and critically assessed. The development of innovative approaches for potential industrial applications, alongside efforts to mitigate the drawbacks of conventional methods, has become imperative. A comparative analysis was conducted, focusing on aspects such as productivity, efficacy, and operational conditions, demonstrating that the novel methods tend to be more environmentally sustainable and cost-effective while delivering the best-quality product in terms of texture, color, expansion factor, and nutritional content attributes
La part de l'étranger dans les positions de jeunes chercheurs et chercheuses
No full textInternational audiencePrésentation du travail de recherche en thèse de Doctorat sur le traducteur Bi Xiushao 毕修勺 (1902-1992) autour d'une table ronde organisée par Eve de Dampierre et Isabelle Poulin, à l'occasion du séminaire La part de l'étranger (MSH Bordeaux / PLURIELLES).Réflexion autour des choix de publications des traductions des romans d’Émile Zola en Chine à travers le filtre du contexte historique chinois et des convictions politiques du traducteur
Interactions Between Corrosion and Biofouling on Bronze in Natural Seawater: Insights from In Situ Analysis
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« Histoire et récits islamiques d'explication du temps : une proposition de typologie »
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Ecological update on the common cuttlefish (Sepia officinalis) in the Bay of Biscay inferred from a multifaceted approach
No full textInternational audienceThe common cuttlefish (Sepia officinalis) is one of the most exploited cephalopods in Europe, yet its population status in the central part of its range, the Bay of Biscay (BoB), remains poorly understood. This study aimed to update knowledge and fill gaps through three complementary approaches: (1) assessing population genomic structure across the BoB and adjacent regions using RAD-sequencing; (2) analyzing spatial and temporal trends from fisheries data; and (3) characterizing life-history traits and reproductive strategies of spawners in two major coastal areas (Pertuis Charentais and Arcachon Bay). Population genomic analyses confirmed no significant structuring between the English Channel and BoB, suggesting substantial gene flow, likely due to mixing at wintering grounds or during migration. In contrast, differentiation from the southern Iberian Peninsula was observed. Fisheries data (2010–2022) highlighted a declining catch-per-unit-effort (CPUE) trend for mature individuals, despite increasing CPUE of sub-adult individuals, but with notable local disparities such as a decline in sub-adults in Arcachon Bay. Life-history analysis confirmed the coexistence of two reproductive strategies, annual (Group I Breeders) and biennial (Group II Breeders), with spatial and phenological variation along a north-south gradient. GIIB individuals dominate early in the season and may be more vulnerable to environmental changes, particularly temperature increase. In the context of climate change, the northward shift in distribution and gradual replacement of biennial breeders by annual breeders in southern areas anticipated, could increase genetic structuring. Future research should prioritize understanding offshore wintering habitats and coastal nursery quality to inform adaptive management of the species
Où sont les légumineuses dans les terroirs de savane sud-soudanienne ?
No full textCe volume fait suite aux Rencontres Francophone Légumineuses (RFL) de mars 2024 organisées par le Cirad, INRAE, Terres Inovia et Terres Univia, et co-organisé par l'Institut Sénégalais de Recherches Agricoles (ISRA). Ce rendez-vous unique entre tous les acteurs du développement, des filières et de la recherche sur les légumineuses à graines et fourragères. L’occasion de croiser les regards, partager les connaissances et accélérer l’innovation autour des légumineuses.Les RFLs s’intéressent aux légumineuses à graines, fourragères ou ligneuses, et visent à couvrir la diversité des systèmes de production, ainsi que la diversité des usages : alimentation humaine, animale et non-alimentaire.Les légumineuses sont un levier majeur pour relever les défis mondiaux du changement climatique et de la sécurité alimentaire et nutritionnelle. Partout dans le monde, elles disposent d’un rôle stratégique : atouts nutritionnels, souveraineté protéique et alimentaire. Les nombreuses espèces de légumineuses constituent également un formidable vivier d’innovations alimentaires.National audienceWith mechanized farming in sudanian climate terroirs (maize, cotton), legumes associated with hardy cereals have both declined. Taking the case of south-west Burkina Faso (social transect of 8 villages, 3 lowlands), on the basis of recent detailed data at individual and farm level, the paper explores the status of legumes, variations and drivers. In fields on dry soils, legumes are still grown in pure stand or in associations, but have fallen since the 1970s, especially in "bush fields". Even cash cropping of groundnuts has given way to cotton. Small non-cotton farms and women still rely on legumes. Large farms have limited them to their food needs, but are testing soybeans, in association or rotation with cotton and maize. Farms disappointed with cotton are interested in groundnut and cowpea in pure stand.Résumé : Avec la culture mécanisée dans les terroirs en climat soudanien (maïs, cotonnier), les céréales rustiques ont reculé, avec leurs légumineuses associées. En prenant le cas du Sud-Ouest du Burkina Faso (transect social de 8 villages, 3 bas-fonds), sur la base de données détaillées récentes à l’échelle individu et exploitation, l’article explore le statut des légumineuses, leurs variations et facteurs sousjacents. Dans les sols secs, les légumineuses restent cultivées en pur ou en association, mais ont chuté depuis les années 1970, surtout dans les « champs de brousse ». Même l’arachide de rente a reculé face au cotonnier. Les petites exploitations sans cotonnier ainsi que les femmes misent encore sur les légumineuses. Les grandes exploitations les ont limitées à leurs besoins alimentaires, mais testent le soja, en association ou rotation avec cotonnier et maïs. Les exploitations déçues du cotonnier sont intéressées par l’arachide et le niébé en culture pure
Coupling genetic and demographic data to reveal dispersal processes in emperor penguins
No full textInternational audienceDispersal is an ubiquitous phenomenon that affects the dynamics of the population and the evolution of natural populations; however, it is challenging to measure in most species.Furthermore, the influence of informed dispersal behaviors, referring to the non-random selection of breeding habitats by individuals, on species' responses to rapid global change is substantial but difficult to comprehend.Here, we present a modeling framework to assess the dispersal characteristics and behaviors of a metapopulation, when observations provide information on its neutral genetic structure for a restricted sampling of locations. Our mechanistic-statistical model couples a deterministic model capturing the spatio-temporal dynamics of four genetic clusters across all breeding colonies by integrating demographic processes with genetic projections, with a probabilistic observation model describing the probability to sample an individual from a given genetic cluster.We apply this new framework to the emperor penguin, a species living in Antarctica and currently experiencing habitat loss. The model estimates the species' dispersal distance, rates of emigration, and behaviors associated with dispersal (informed or random). By incorporating these estimations with satellite censuses of breeding colonies, we can identify environmental and demographic factors that influence the { dispersal} of emperor penguins. Finally, we provide new global population forecasts for emperor penguins that can inform conservation actions in Antarctica