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Mapping the Human Chemical Exposome for Public Health
No full textInternational audienceExcitons in the weakly interacting regime can be well-described by many-body perturbation theo-ries such as the Bethe-Salpeter equation formalism. However, for materials such as transition metaldichalcogenides moir´e heterostructures under strong illumination, with the emergence of dense ex-citonic states, the strong correlation and entanglement between electrons and holes may cause themany-body perturbation method to fail, and excitons may not be treated in the bosonic picture,but exhibit fermionic behaviors. In our work, we investigate the phase space where excitons, andthe electrons and holes which constitute them, are weakly or strongly entangled, as well as theirbinding for different interaction profiles and the degree of localization of the electrons and holes. Wecorroborate the validity of using many-body perturbation theory in the exciton with interactions.Our work provides a general way to analyze the correlation and entanglement of multi-particle ex-citations in many-body systems, and gives a more comprehensive understanding of different phasesfor exciton entanglement and interactions in 1D systems
Caste-specific functional variation in the venom of the army ant Eciton hamatum
No full textInternational audienceIn ants, division of labor is often associated with caste-specific adaptations. In this study, we examined the morphology of the venom apparatus (venom reservoir volume and sting length) and the composition and activity of the venom across castes (soldier, submajor, and media/minor) of the army ant Eciton hamatum to investigate how caste differentiation influences venom traits. Morphometric analyses revealed that soldiers have larger venom reservoirs and longer stings, consistent with their specialized role in defending the colony against vertebrates. Integrative venom profiling using transcriptomics and mass spectrometry identified 11 venom peptides, including a glycopeptide bearing a complex N-glycan. Notably, soldiers had a streamlined venom peptide composition compared with other castes. Despite this reduced complexity, soldier venom was more potent in functional assays, showing enhanced paralytic effects on insect prey and stronger pain-inducing activity on vertebrate neurons. Chymotrypsin enzymes, more abundant in the venoms of soldier castes, may also serve a predigestive role. This pattern suggests an evolutionary trade-off favoring a limited set of highly effective components tailored to the dual function of defense and predation in soldiers.</div
L'importance de la coopération dans les politiques de conservation de la biodiversité
No full textInternational audienceCollective schemes are promising tools for improving biodiversity conservation policies within rural landscapes. Yet, despite being at the core of their design, cooperation and its underlying mechanisms have seldom been addressed explicitly by the literature on the topic. Our paper addresses this gap in the case of the agglomeration bonus (AB), by assessing the benefits of landowners’ cooperation in conserving biodiversity through ABs with varying degrees of “collectiveness” (i.e., differing in terms of the “rules” governing landowners’ enrollment into the AB). Methodologically, we couple an ecological-economic model with a group formation game to endogenize both landowners’ cooperation and conservation responses to ABs characterized by different landowner-level enrollment rules and plot-level payments. Solving the model numerically on fictitious landscapes, we show that larger groups conserve biodiversity more cost-effectively. Findings indicate that the “value of cooperation” – defined as the difference in biodiversity achieved through collective vs. individual responses to the same plot-level payments – amounts to between 10 and 45 percent. As it leads to the highest degree of cooperation, we show that “open-list ABs” are generally the most cost-effective schemes, followed by “closed-list ABs” (where, contrary to open-list ABs, landowners can exclude someone from the group), “individual ABs” (where “groups” are limited to one landowner), and, finally, standard homogeneous payments (where bonuses are null). These results stress the importance of the very design of collective schemes to boost the effectiveness of conservation policies.Les dispositifs collectifs constituent des outils prometteurs pour améliorer les politiques de conservation de la biodiversité dans les espaces ruraux. Pourtant, bien qu’elles soient au cœur de leur conception, la coopération et ses mécanismes sous-jacents ont rarement été abordés de manière explicite dans la littérature sur le sujet. Notre article comble cette lacune dans le cas du bonus d'agglomération (BA), en évaluant les avantages de la coopération des propriétaires fonciers pour la conservation de la biodiversité par le biais de BA présentant différents degrés de « collectivité » (c'est-à-dire différant en termes de « règles » régissant l'adhésion des propriétaires fonciers au BA). Sur le plan méthodologique, nous associons un modèle éco-économique à un jeu de formation de groupes afin d’endogéniser à la fois la coopération des propriétaires fonciers et les réponses de conservation aux AB caractérisées par différentes règles d’adhésion au niveau des propriétaires fonciers et différents paiements au niveau des parcelles. En résolvant le modèle numériquement sur des paysages fictifs, nous montrons que les groupes plus importants préservent la biodiversité de manière plus rentable. Les résultats indiquent que la « valeur de la coopération » – définie comme la différence de biodiversité obtenue grâce à des réponses collectives par rapport à des réponses individuelles aux mêmes paiements au niveau des parcelles – se situe entre 10 et 45 %. Comme ils conduisent au plus haut degré de coopération, nous montrons que les « AB à liste ouverte » sont généralement les programmes les plus rentables, suivis des « AB à liste fermée » (où, contrairement aux AB à liste ouverte, les propriétaires fonciers peuvent exclure quelqu’un du groupe), des « AB individuels » (où les « groupes » se limitent à un seul propriétaire foncier) et, enfin, des paiements homogènes standard (où les primes sont nulles). Ces résultats soulignent l’importance de la conception même des dispositifs collectifs pour renforcer l’efficacité des politiques de conservation
L'utilisation des eaux souterraines en Inde serait-elle peu durable ?
No full textInternational audienceIn many parts of the world, groundwater is being extracted at rates that exceed natural renewal rates, leading many experts to conclude that groundwater mining is an unsustainable strategy for rural development. However, groundwater extraction could still be considered to be ‘weakly sustainable’ if it generates investments in man-made capital that offset the loss of natural ‘groundwater capital’ and enable income to be sustained even as the resource is depleted. In this paper, we examine whether the withdrawals of groundwater for irrigation in India have resulted in household-level investments in physical and human capital. Our empirical strategy compares villages in the same administrative units that overlie aquifers with different water storage capacities and, therefore, endowed with different levels of access to the resource. We find that greater access to the resource results in more irrigation, as expected, as well as higher asset wealth and educational attainment. The results suggest that deeming India’s irrigation-based rural development as unsustainable purely because of the decline in water tables may require reconsideration, provided that human capital is used to productively shift income from farm to off-farm sources.Dans de nombreuses régions du monde, l’eau souterraine est prélevée à des rythmes qui dépassent les taux de renouvellement naturel, ce qui conduit de nombreux experts à conclure que l’exploitation des nappes phréatiques constitue une stratégie non durable pour le développement rural. Cependant, le prélèvement d’eau souterraine pourrait tout de même être considéré comme « faiblement durable » s’il génère des investissements en capital physique qui compensent la perte du « capital souterrain » naturel et permettent de maintenir les revenus même lorsque la ressource s’épuise. Dans cet article, nous examinons si les prélèvements d’eau souterraine à des fins d’irrigation en Inde ont entraîné des investissements au niveau des ménages dans le capital physique et humain. Notre stratégie empirique compare des villages situés dans les mêmes unités administratives qui recouvrent des aquifères ayant des capacités de stockage d’eau différentes et qui, par conséquent, bénéficient de niveaux d’accès à la ressource différents. Nous constatons que, comme prévu, un meilleur accès à la ressource se traduit par une irrigation plus importante, ainsi que par une plus grande richesse en actifs et un niveau d’éducation plus élevé. Les résultats suggèrent qu’il convient de reconsidérer l’idée selon laquelle le développement rural indien fondé sur l’irrigation serait non durable uniquement en raison de la baisse des nappes phréatiques, à condition que le capital humain soit utilisé pour transférer de manière productive les revenus des sources agricoles vers des sources non agricoles
Spatio-temporal evaluation of EpiDCA: Case studies on avian influenza, African swine fever, and West Nile virus disease
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/617037/)International audienceEvent-Based Surveillance (EBS) systems play an important role in the early detection of disease outbreaks by monitoring unstructured data sources. However, they face key challenges, including handling the overwhelming volume of collected articles, detecting false positives, and the lack of explainability in detected events. To address these limitations, we previously developed EpiDCA, an unsupervised model that integrates epidemiological and environmental data, as well as expert-defined parameters, into the classification process. Its initial application to avian influenza (AI) in Asia demonstrated very promising results, comparable to well-known supervised baseline methods. In this paper, we assess the robustness and genericity of EpiDCA by applying it to three different case studies: AI in France, African swine fever (ASF) in Europe, and West Nile virus disease (WND) in Europe. Results showed that EpiDCA effectively distinguishes relevant from irrelevant events, achieving weighted F-scores between 0.64-0.85 across all case studies. Sensitivity analysis demonstrated model robustness, with most parameters showing minimal influence on results. Notably, the incorporation of environmental data and finer spatial granularity significantly improved classification precision. Overall, EpiDCA remains robust and adaptable across diverse epidemiological contexts, further validating its effectiveness as a valuable tool for event-based surveillance, with improved interpretability and real-time classification
Advancing optical earth observation for EU policies: needs, opportunities, recommendations
No full textInternational audienceThe effective translation of Earth observation (EO) measurements into actionable information for agriculture and land monitoring is critical to support policy implementation on climate, environment, and sustainable development. However, this translation remains challenging, as EO evolves from an awareness-raising instrument into an operational tool for evidence-based policymaking. To address this gap, we systematically link, for the first time, European Union (EU) land-related agricultural and environmental policies to EO-derived variables that can be generated from enhanced optical satellites expected in the next decade. We present a comprehensive framework for assessing the technology readiness levels (TRLs) of EO variables used to map, monitor, and manage crop, forest, soil, mineral, and water resources, thereby facilitating policy implementation and compliance. Upcoming Copernicus Hyperspectral Imaging Mission for the Environment (CHIME), and the Sentinel-2 Next Generation (S2NG) missions, both developed by the European Space Agency (ESA), will deliver substantial technological advancements for high-level EO-based products, enabling applications such as plant nitrogen and soil organic carbon content (SOC) estimation, species identification, and water quality characterization. Realizing the full potential of CHIME and S2NG for agricultural and environmental policy implementation will require advancing current products from prototype stages (TRL 4-6) to full operational readiness (TRL 9) through robust science-policy interfaces. Within such interfaces, we recommend exploiting existing (hyperspectral) EO data and time series, strengthening in-situ observations for robust model development and validation, and testing synergies between systems. Co-design of tailored products with policymakers is then essential to refine algorithms and align EO outputs with regulatory needs and scales. Upcoming spaceborne imaging spectroscopy and enhanced multispectral data streams thus have the potential to become game-changers and indispensable tools for EU policy implementation, providing greater traceability of key environmental and agricultural processes
Etude scientifique et participative sur la qualité du sol et de l’air et sur la perception des pollutions par les habitants dans la zone Sebikotane-Diamniadio, Sénégal - Résultats du projet AirGeo (2021 – 2024)
No full textIntestinal microbiome in very-preterm infants at one month of age and association with neurodevelopmental outcome
No full textInternational audienceBackground: Preterm birth is the leading cause of death in children under five years of age worldwide. The association between preterm birth and long-term outcomes is vaguely known. In very preterm infants, the gut microbiome is highly variable and impacted by the neonatal intensive care unit environment. Our objective was to better understand the crosstalk between the gut microbiome and the host at one month of age in very preterm infants and its impact on neurological outcomes at two years of age. We performed a multi-omics analysis of fecal samples collected in 2011 from 73 very preterm French infants at one month of age, grouped according to their neurodevelopment assessed at two years of age using the Ages & Stages questionnaire. Multi-omics profiling and integrative analyses were performed between 2022 and 2023, including fecal microbiome, metabolome, and host transcriptome characterization using 16S rRNA gene sequencing, LC-MS, and mRNA sequencing, respectively. Results:The gut microbiome of very preterm infants at one month is mostly driven by either Escherichia or Staphylococcus, which are differentially associated with host immune markers (CAMP), metabolomic pathways, notably the energy pathway due to the presence of various nicotinamide adenine dinucleotides (NAD+) and two-year neurodevelopmental outcomes. Conclusion:The gut microbiome at one month of age could be a noninvasive biomarker of gut immaturity and metabolic defects. Escherichia and Staphylococcus proportions were found to be the best indicators of physiological</div
Récits et narratifs d’un changement de paradigme
No full textInternational audienceL’action en faveur d’un monde soutenable pour l’humanité est possible à conditionde prendre la mesure du défi. Dans son adresse aux décideur•se•s, l’IPBESindique par exemple « qu’il est possible de conserver, de restaurer et d’utiliser lanature de manière durable et, en même temps, d’atteindre d’autres objectifs sociétauxà l’échelle mondiale en déployant de toute urgence des efforts concertés quientraînent des changements en profondeur » (IPBES 2019, message D). Au-delà dela dimension politique de cette affirmation, appréhender de tels changements, structurels,fondamentaux, nous impose de prendre conscience de ce qui se joue dansles défis écologiques auxquels nos sociétés sont confrontées, de comprendre que lemonde va changer, radicalement et qu’on le veuille ou non, et de comprendre aussien quoi cela questionne nos valeurs, nos croyances et nos manières d’agir. Cela nousdemande d’appréhender de nouveaux récits de mondes soutenables
Is Collaborative Groundwater Governance Really Unfit for Purpose in Low-and Middle-Income Countries? Evidence from Morocco
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616925/) * Autres projets (id;sigle;titre): ;eGROUNDWATER;(EU) Citizen science and ICT-based enhanced information systems for groundwater assessment, modelling and sustainable participatory management// 101102316;ERA-LEARN;(EU) Strengthening the European Partnership community//International audienceAttempts to establish collaborative groundwater governance (CGG) have so far generally produced limited results in low-and middle-income countries. These shortcomings have been attributed to the high transaction costs associated with such approaches, making them impractical in informal water economies. This paper examines the obstacles to designing and implementing such an approach, through the analysis of a multistakeholder process conducted in a groundwater-depleted area in Northern Morocco. The process brought together farmers, staff members of public organisations, and other stakeholders to explore options for CGG. During the process, farmers created groundwater users associations and together the participants drafted an aquifer contract. The participatory process helped overcome several obstacles to CGG, particularly those related to farmers' engagement. The finalisation of the aquifer contract was put on hold, however, due to the limited follow-up by state actors, the insufficient coordination among the numerous public actors involved, and weak political support.The study shows that CGG may not be inherently unfit for purpose in at least some low-and middle-income countries. Moreover, the participatory design of CGG can be an opportunity for horizontal dialogue between farmers operating in informal water economies and state administrations