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Eco-epidemiological thresholds for malaria transmission in multi-species, phenotypically structured mosquito populations
No full textUnderstanding how vector richness influences malaria transmission remains a critical challenge in disease ecology and public health. We develop a mathematical model that integrates both interspecific and intraspecific phenotypic diversity within mosquito populations, structured by chronological age and continuous phenotypic traits. Our framework couples these diverse mosquito populations with a human host population to analyze the eco-epidemiological dynamics of malaria transmission. We conduct a detailed analysis of the mosquito population's asymptotic behavior and invasibility analysis. Additionally, we identify an eco-epidemiological threshold parameter that synthesizes mosquito vectorial capacity, intrinsic fitness differences, and ecological competition to predict whether the addition of a new mosquito species amplifies or dilutes epidemic risk. Through this approach, we show that vector species abundance alone is insufficient to determine malaria transmission potential; rather, the interplay between phenotypic variation and ecological interactions governs epidemic outcomes. Our results generalize and extend previous theoretical studies by incorporating structured population dynamics and continuous trait variation, providing a mechanistic basis for anticipating how changes in mosquito community composition may impact malaria transmission risk
Asymmetric bioactive phosphorus dendrimers deliver bromelain for enhanced anti-inflammation and chondroprotection therapy of osteoarthritis
No full textInternational audienceIt is still challenging to develop nanomedicines with full-active and simple components to tackle osteoarthritis (OA) through restoration of inflammation and cartilage homeostasis. Here, we report the synthesis of a bioactive asymmetric phosphorus dendrimer bearing an azabisphosphonate (ABP) group, termed as G0.PD-ABP, by a divergent method for intracellular bromelain (Bro) delivery. The formed G0.PD-ABP/Bro nanocomplexes (NCs) exhibit a uniformly dispersed spherical shape with a mean size of 148.4 nm and can achieve more significant intracellular Bro delivery than symmetric phosphorus dendrimer (G0.PD) without ABP via the clathrin-mediated endocytosis pathway. Importantly, the NCs efficiently block the activation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor kappa-B (NF-κB) by amplifying the anti-inflammatory function of Bro and synergizing with the immunomodulatory activity of dendrimers, thereby facilitating the polarization of macrophages towards M2 phenotype and down-regulating inflammatory cytokine secretion to lead to suppressed chondrocyte apoptosis. Compared with G0.PD/Bro NCs, an OA mouse model treated with G0.PD-ABP/Bro NCs demonstrates more remarkable alleviation of pathological features such as cartilage degradation, bone erosion, and synovial inflammation. This study emphasizes the positive contribution of structural asymmetry of phosphorus dendrimers in protein delivery and provides a viable strategy for the treatment of OA or other inflammatory diseases through enhanced immune modulation of macrophages
Preservation of organic traces of life under Martian conditions: Influence of the nature of the smectite in presence
No full textInternational audienceClay-rich Martian rocks are considered promising targets in the search for fossilized remains of ancient Martian life. However, the actual influence of the clay mineral compositions in preserving microbial biosignatures remains poorly understood. Here, we explore the biopreservation potential of three pure smectites typically found on Mars and containing Al in their tetrahedral sheets (i.e. a Mg-rich, a Fe-rich and a Al-rich smectite), relying on experiments run using E. coli as a biological analog to simulate hydrothermal alteration scenarios relevant to Mars. The results show that Mg-rich smectites (saponite) are more effective at preserving biomolecules from thermal degradation than Fe-rich and Al-rich smectites (nontronite and beidellite). Plus, in contrast to saponite, neither nontronite nor beidellite appears to significantly trap (and thus preserve) organic compounds within their interlayer spaces. Overall, the present study highlights that both the chemistry and the abundance of organic material in ancient Martian clay-rich rocks will depend on the compositional nature of smectites initially present
Digging deeper: deep joint species distribution modeling reveals environmental drivers of Earthworm Communities
No full textInternational audienceEarthworms are key drivers of soil function, influencing organic matter turnover, nutrient cycling, and soil structure. Understanding the environmental controls on their distribution is essential for predicting the impacts of land use and climate change on soil ecosystems. While local studies have identified abiotic drivers of earthworm communities, broad-scale spatial patterns remain underexplored. We developed a multi-species, multi-task deep learning model to jointly predict the distribution of 77 earthworm species across metropolitan France, using historical (1960–1970) and contemporary (1990–2020) records. The model integrates climate, soil, and land cover variables to estimate habitat suitability. We applied SHapley Additive exPlanations (SHAP) to identify key environmental drivers and used species clustering to reveal ecological response groups. The joint model achieved high predictive performance (TSS >0.7) and improved predictions for rare species compared to traditional species distribution models. Shared feature extraction across species allowed for more robust identification of common and contrasting environmental responses. Precipitation variability, temperature seasonality, and land cover emerged as dominant predictors of earthworm distribution but differed in ranking across species and functional groups. Species clustering into response groups to climatic, land use and soil revealed distinct ecological strategies including a gradient of sensitivity to precipitation seasonality, differential habitat preferences in terms of vegetation cover and wetness and trade-offs between soil acidity and organic matter quality. Our study advances both the methodological and ecological understanding of soil biodiversity. We demonstrate the utility of interpretable deep learning approaches for large-scale soil fauna modeling and provide new insights into earthworm habitat specialization. These findings highlight land cover and seasonal climate variability as efficient proxies for soil biodiversity, providing actionable indicators for global monitoring initiatives and helping to identify habitat requirements of earthworm species to guide emerging earthworm conservation strategies in the face of global environmental change
Beyond N and P fertilization: Tropical ground hexapod communities are tied to micronutrients
No full textInternational audienc
Pyrroline-5-carboxylate dehydrogenase is a key actor of nitrogen metabolism in maturing seeds of Arabidopsis thaliana: P5CDH and seed development
No full textInternational audienceProline is a multifaceted amino acid in plants involved in both stress responses and development. Recent studies have shown that knock-out mutants lacking Pyrroline-5-carboxylate dehydrogenase (P5CDH), the enzyme responsible for the second step of proline catabolism, impaired nitrogen remobilisation and carbon allocation to seeds. Here, we demonstrate that seed development is also significantly impaired in p5cdh mutants, particularly from the transition between embryogenesis and maturation. Specifically, the p5cdh mutation leads to an arrest in embryo elongation and a reprogramming of seed metabolism during maturation, resulting in reduced accumulation of storage compounds and compromised acquisition of dehydration tolerance. These effects are further exacerbated under high nitrate conditions. Together, our findings highlight a crucial role for proline catabolism in supporting the ability of maturing embryos to utilize glutamine as a nitrogen source, particularly in response to nitrogen availability
Ocean 2: A Co-designed Belmont Forum Action for Biodiversity and the Ocean We Want
No full textThe Belmont Forum fosters transdisciplinary sustainability research through its Collaborative Research Actions (CRAs). In 2018, the Oceans CRA was launched to advance knowledge and solutions for sustainable use of ocean resources, resulting in 13 multilateral projects involving researchers and societal actors from 16 countries. Building on these achievements, Ocean 2 was developed during the final phase of the Oceans CRA and endorsed as a contribution to the UN Decade of Ocean Science for Sustainable Development (2021-2030). Ocean 2 expands the scope of its predecessor by emphasizing biodiversity conservation, nature-based solutions, the integration of biodiversity with climate and ocean dynamics in line with nexus approaches sensu IPBES and the Convention on Biological Diversity’s 2050 Vision of “Living in Harmony with Nature,” and the attention to ethics, governance, and the use of scenarios as tools to foresee desirable futures for ocean biodiversity in relation to society. Here we describe the co-design process that led to the formulation of Ocean 2, an initiative of the French Alliance for Environmental Research refined through eight scoping workshops held worldwide in 2024. Two complementary formats—hybrid sessions at international conferences and fully online workshops—were used to engage researchers and societal actors across disciplines, sectors, regions and world-views. Input was synthesized to identify central themes, which informed the final Call text adopted by Belmont Forum members in 2025. The Ocean 2 CRA call was opened in June 2025, with applications due in March 2026. By combining structured co-design, global outreach, and integration with the Ocean Decade’s 10 Challenges, Ocean 2 is a step towards building inclusive, transdisciplinary, and solution-oriented research agendas for the ocean we want
Econometrics at the Extreme: From Quantile Regression to QFAVAR 1
No full textThis paper surveys quantile modelling from its theoretical origins to current advances. We organize the literature and present core econometric formulations and estimation methods for: (i) cross-sectional quantile regression; (ii) quantile time-series models and their time-series properties; (iii) quantile vector autoregressions for multivariate data; (iv) quantile panel models for longitudinal data; and (v) quantile factor-augmented models for information compression in data-rich environments. Each section outlines theoretical foundations and developments, followed by representative empirical applications. Finally, the survey highlights open gaps in quantile modelling. By studying distributional dynamics beyond averages, quantile methods provide policymakers and regulators with tools to design interventions that are robust to risks and effective across the entire spectrum of possible outcomes
The Global Spectra-Trait Initiative: A database of paired leaf spectroscopy and functional traits associated with leaf photosynthetic capacity
No full textInternational audienceAccurate assessment of leaf functional traits is crucial for a diverse range of applications from crop phenotyping to parameterizing global climate models. Leaf reflectance spectroscopy offers a promising avenue to advance ecological and agricultural research by complementing traditional, time-consuming gas exchange measurements. However, the development of robust hyperspectral models for predicting leaf photosynthetic capacity and associated traits from reflectance data has been hindered by limited data availability across species and environments. Here we introduce the Global Spectra-Trait Initiative (GSTI), a collaborative repository of paired leaf hyperspectral and gas exchange measurements from diverse ecosystems. The GSTI repository currently encompasses over 7500 observations from 397 species and 41 sites gathered from 36 published and unpublished studies, thereby offering a key resource for developing and validating hyperspectral models of leaf photosynthetic capacity. The GSTI database is developed on GitHub (https://github.com/plantphys/gsti, last access: 4 January 2026) and published to ESS-DIVE https://doi.org/10.15485/2530733, Lamour et al., 2025). It includes gas exchange data, derived photosynthetic parameters, and key leaf traits often associated with traditional gas exchange measurements such as leaf mass per area and leaf elemental composition. By providing a standardized repository for data sharing and analysis, we present a critical step towards creating hyperspectral models for predicting photosynthetic traits and associated leaf traits for terrestrial plants
Entre transfert de technologie et coopération Sud-Sud : une expérimentation indo-cubaine en matière d’innovation biopharmaceutique
No full textInternational audienceThe collaboration between the Cuban Centre of Molecular Immunology (CIM) and the Indian firm Biocon challenges conventional understandings of technology transfer. Initiated in 2003, the joint venture was a unique experiment in South-South biopharmaceutical collaboration. It brought into relation two distinct innovation regimes: Cuba's public health-oriented model, closely tied to the state and its medical diplomacy, and India's market-driven biopharmaceutical industry. However, both regimes were animated by postcolonial aspirations for technoscientific emergence in the Global South. The partnership ultimately dissolved, as structural tensions and divergent industrial objectives proved difficult to reconcile. But its apparent failure was also productive. For CIM, it opened access to resources lacking in Cuba and enabled clinical trials on a wider population. For Biocon, it offered research, development, and manufacturing expertise that supported its rise in the global biosimilar market. Drawing on interviews with key actors in Cuba and India, this study situates the partnership within broader debates on innovation regimes, postcolonial science, and the inequalities that shape the global biopharmaceutical economy. The article shows how South-South collaborations, even when framed as alternatives to asymmetric North-South models, remain entangled in (bio)capitalist logics while still opening possibilities for reimagining technological exchange beyond dominant North/South narratives.La collaboration entre le Centre cubain d’immunologie moléculaire (CIM) et la firme indienne Biocon remet en question les conceptions conventionnelles du transfert de technologie. Lancée en 2003, la coentreprise constituait une expérience unique de collaboration biopharmaceutique Sud-Sud. Elle mettait en relation deux régimes d’innovation distincts : le modèle cubain, orienté vers la santé publique et étroitement lié à l’État ainsi qu’à sa diplomatie médicale, et l’industrie biopharmaceutique indienne, guidée par le marché. Ces deux régimes étaient animés par des aspirations postcoloniales à l’émergence technoscientifique dans le Sud global. Le partenariat a finalement été dissous — les tensions structurelles et la divergence dans les objectifs industriels se révélant difficiles à concilier, mais cet apparent échec fut aussi productif. Pour le CIM, il a permis l’accès à des ressources qui faisaient défaut à Cuba et l’ouverture d’essais cliniques sur une population plus large. Pour Biocon, il a offert une expertise en recherche, développement et production qui a soutenu son ascension sur le marché mondial des biosimilaires. S’appuyant sur des entretiens menés auprès d’acteurs clés à Cuba et en Inde, cette étude situe le partenariat au croisement des débats sur les régimes d’innovation, la science postcoloniale et les inégalités qui structurent l’économie biopharmaceutique mondiale. L’article montre comment les collaborations Sud-Sud, même lorsqu’elles se présentent comme des alternatives aux modèles asymétriques Nord-Sud, demeurent prises dans des logiques (bio)capitalistes, tout en ouvrant la possibilité de réimaginer les échanges technologiques au-delà des récits dominants Nord/Sud