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A la carte dissolution of rare earth elements from lateritic and karstic bauxite residues at mild pH: Toward sustainable extraction processes
No full textInternational audienceRecovery of rare earth elements from bauxite residues of lateritic versus karstic origin was explored at a pH ranging between 2.7 and 4.5 using a mixture of citric acid and citrate in water. Dissolution yields of up to 82 % for lanthanum and 62 % for yttrium were achieved with excellent selectivity toward iron (a selectivity factor of up to 4200), the main element of bauxite residues. An experimental Box-Behnken statistical design identified the concentration of citric acid/citrate and temperature as key factors controlling the dissolution yield and selectivity of rare earth elements. Observed differences in dissolution yields and selectivity as a function of origin were attributed to differences in the speciation of rare earth elements in the two bauxite residues. It is therefore possible to draw an "à la carte" graph that identified the optimum citric acid/citrate concentrations and dissolution temperatures for dissolution yields and selectivity for the two BRs. This work provides fundamental knowledge for the future development of sustainable processes for the recovery of rare earth elements from bauxite residues derived from bauxites of different origin
« Reading landscape » 讀景 in a Mediterranean peri-alpine catchment basin: (Vallée des Duyes, Geopark UNESCO of Haute Provence, Alpes de Haute Provence, France)
No full textInternational audienceNota bene: this oral presentation in English is based on an article written in French that will be published in September 2025 Christian Depraetere, Benoît Deffontaines, Jiun-Chuan Lin, Jean-Simon Pagès, 2025. Évènements hydroclimatiques passés et actuels dans le bassin versant de la vallée des Duyes (Alpes de Haute-Provence). Revue Méditerranée, accepté pour publication.Located in the UNESCO Geopark of Haute Provence, the Duyes watershed is representative of the hydrodynamic processes of the Mediterranean peri-alpine mid-mountains with deformed sedimentary bedrock. The local archives record a major hydroclimatic event associated with ten days of heavy rainfalls affecting this valley in April 1774 with a large-scale landslide with several damages: sinking of arable land, catastrophic flooding, destruction of buildings and roads. The archives describe the events in the terms of the time: "continuous rainfall", "abundance of water from the torrents", "revolution of the earth", "openings and crevasses", etc. The documents also point out that these "strange inconceivable revolutions" were concomitantly associated with two earthquake tremors without stating if this was a cause or a consequence of the detachment of several millions tons of rock and mud masses. This event took place at the end of the Little Ice Age (LIA, 1350-1850) in the context of a densely populated rural world practicing traditional peasant polyculture in the form of mid-mountain extensive agropastoralism.The first part presents and comments the 1774 archives as an example of a geohistorian's work. The second part details the climatic and hydrogeomorphological contexts of the valley at the time based on field observations and current data, including morphometric mapping using the LIDAR digital terrain model (DTM) and torrential flood simulations. Extensive fieldworks and the expertise of the local population also form the backbone of this study. Current flood and landslide risks are briefly recalled, based on the climatology of the years 2022 to 2024, in particular in May 2023 when heavy rainfall caused gullying of dirt roads and landings at the foot of steep fields and pastures in many valley locations.This research aims to contribute to the geohistory of the environmental and human societies co-evolution, and more specifically on the interactions between hydrogeomorphological processes and the dynamics of anthropized agrofestry landscapes in Mediterranean mountain regions. It also stresses the value of practical training in “landscape reading”, following the pedagogical principle of 讀景 put forward by Professor Jiun-Chuan Lin in his magnum opus on applied geomorphology (地形學,2022)
Effects of co-exposure to benzo-a-pyrene and cerium dioxide nanoparticles on human lung and placental barriers
No full textInternational audienceCerium dioxide nanoparticles (CeO2 NPs) are emerging pollutants widely used for their catalytic properties in diesel fuel and cigarettes. Human exposure to CeO2 NPs rarely occurs in isolation. Benzo-a-pyrene (BaP), a polycyclic aromatic hydrocarbon co-emitted from diesel engines, tends to adsorb onto CeO2 NPs in contaminated environments. To better understand their combined effects on both the lung and placental tissues which arecritical-barriers for the fetus, we coated CeO2 NPs with BaP at two different ratios, mimicking environmental exposure. We characterized the physicochemical properties of BaP-coated NPs in bronchial and placental culture media, assessed coating stability and BaP desorption. We evaluated the biological impact of BaP-coated CeO2 NPs son primary normal human bronchial epithelial cells and purified villous cytotrophoblasts from term human placentas. We compared the response of BaP-coated NPs with that observed under parallel co-exposure, and to individual exposures to BaP and CeO2 NPs. Bronchial cells exhibited toxicity at lower doses under co-exposure by parallel addition compared to BaP-coated NPs. Cytochrome P450 (CYP1A1) induction varied between tissue barriers, exhibiting a BaP dose-dependent response in both tissue models but coating-independent response in trophoblasts, whereas bronchial cells showed a stronger response to BaP adsorbed on CeO₂ NPs. These findings highlight how BaP, when stably associated with CeO2 NPs, exerts modulated effects depending on the tissue,potentially altering its metabolic kinetics and thus its biopersistence. This study underscores the importance ofconsidering particle-bound pollutants when evaluating the health impact of airborne particulate matter, as thismore accurately reflects environmental exposur
Complex interactions between the gut microbiota, pesticide contamination and physiological traits in grey partridges
No full textThe intensification of agriculture in recent years, particularly through the massive use of pesticides and fertilizers, has caused a decline in biodiversity, specifically among farmland birds. Emerging research highlights the adverse effects of chronic and low-dose pesticide exposure, particularly on the gut microbiota, which is essential for host metabolism and immune health. Understanding how pesticides disrupt microbial diversity and physiological traits is thus critical to inform management and conservation strategies. This study examines the impact of pesticide contamination on the gut microbiota composition and physiological responses of captive-bred male grey partridges, a threatened species frequently exposed to pesticide cocktail residues through their habitat and diet. We detected residues of 27 pesticide molecules in the birds' blood, including fungicides, herbicides, and insecticides. Among the different microbial diversity metrics analysed, only bacterial richness was significantly affected by the interaction between pesticide load and body condition, with contrasting effects observed across different body condition groups. Furthermore, higher microbial diversity was positively associated with hematocrit levels, suggesting that microbial diversity may be related to the physiological health of birds. These findings highlight the complex relationship between pesticide exposure, gut microbiota, and host physiology, emphasizing the need for further research to understand these interactions in wildlife health
Predictive metabolomic to decipher plant eco-evolutive tendencies
No full textInternational audienceMetabolomics serve as a powerful tool for understanding the biochemical diversity of plants and its relationship with ecological characteristics [1]. Plant metabolic signatures reflect their adaptive strategies, which influence their functional groups, growth forms, and phenological patterns [2]. Recent advancements in machine learning have enhanced the classification and prediction of biological traits derived from complex biochemical datasets [3]. However, the use of metabolomic data for predicting ecological and evolutionary trends in plants remains mostly underexplored. We analyzed the metabolomic profiles of 74 plant species from 38 plant families grown under natural conditions. Different machine learning models were used and enabled us to identify metabolic signatures associated with plant functional groups, growth forms, and phenology with high accuracy, revealing significant correlations between metabolites and botanical traits. Our results demonstrate that metabolomic profiling, along with machine learning, can effectively predict ecological and evolutionary trends in plants. This approach provides a new framework for investigating plant adaptation and ecological strategies.References1. Fiehn O. Metabolomics--the link between genotypes and phenotypes. Plant Mol Biol. 2002 Jan;48(1–2):155–71.2. Petrén H, Anaia RA, Aragam KS, Bräutigam A, Eckert S, Heinen R, et al. Understanding the chemodiversity of plants: Quantification, variation and ecological function. Ecological Monographs. 2024 Nov 1;94(4):e1635.3. Dussarrat T, Prigent S, Latorre C, Bernillon S, Flandin A, Díaz FP, et al. Predictive metabolomics of multiple Atacama plant species unveils a core set of generic metabolites for extreme climate resilience. New Phytologist. 2022;234(5):1614–28
Potential of service plants for regulating multiple pests while limiting disservices in agroecosystems. A review
No full textInternational audienceService plants are primarily used in agroecosystems to provide ecosystem services that are not directly marketable. They are a promising option to promote biological pest regulation. Past studies have demonstrated their usefulness for regulating one pest category (either pathogens/parasites, herbivores or weeds). However, a multi-pest view of the role of service plants, including the potential disservices (negative impacts) that they may generate, is lacking. Such an overview is essential to meet the challenge of agroecology. This paper aims to fill this gap. Here, a trait-based approach was used to provide an overview of the potentialities of service plants, (inserted either in intercropping, in rotation with the crops, or in field edges) for regulating multiple pests, while limiting disservices. For that purpose, we first laid the foundation of a conceptual framework by synthesizing the mechanisms and service plant traits involved in the regulation of each pest category and in the mitigation of each disservice. On this basis, we analyzed (1) the compatibility in the regulation of the different pests by service plants, and (2) the compatibility between multi-pest regulation vs disservice mitigation. Our main conclusions are: (1) Despite knowledge gaps, there is good potential of service plants for multi-pest regulation; (2) The challenge lies at least as much to mitigate disservices that service plants may cause as to promote multi-pest regulation; (3) The level of incompatibility between promoting multi-pest regulation vs mitigating disservices varies with the mode of insertion of service plants, increasing with interactions with crop plants. This review shows how a trait-based approach can be used to synthesize knowledge from different disciplines and provides a tool for cross-disciplinary dialogue. It identifies priority research actions that are needed to increase synergy, genericity and adaptation of service plants to local conditions, and provides foundations for the design of service-plant based agroecosystems
Tuberculosis disease characteristics associated with mortality, severe morbidity and unsuccessful treatment in people living with HIV treated for tuberculosis - a secondary analysis of the ANRS 12300 Reflate TB2 trial
No full textInternational audienceBACKGROUND: Tuberculosis is a severe disease, not only due to its lethality but also to a significant morbidity occurring in people living with HIV (PLWH). If factors associated to mortality, severe morbidity and unsuccessful treatment related to the host are well identified in PLWH, there is scarce knowledge on factors related to the disease itself such as bacillary load, extent of lung involvement and disease dissemination to other organs. We sought to assess whether tuberculosis-related factors were associated with key patient outcomes in PLWH using data from an international clinical trial. METHODS: We conducted a secondary analysis of the ANRS 12300 Reflate TB2, an international phase III open-label randomized trial that assessed different antiretroviral regimens in PLWH treated for tuberculosis. We evaluated whether bacillary load (smear positivity grade), extent of lung involvement (cavitation on chest x-ray) and disease dissemination (urine LAM positivity) were associated with mortality using Cox proportional hazard models, and to severe morbidity and unsuccessful tuberculosis treatment using logistic regressions. RESULTS: Of 457 participants included in this study, 90 (20.4%) had grade 2 + or 3 + smear positivity, 39 (10.8%) had cavitation on chest X-ray, and 147 (32.2%) had a positive urinary LAM. Overall, 19 (4.2%) participants died, 113 (24.7%) presented severe morbidity, and 33 (7.2%) had unsuccessful tuberculosis treatment. Factors that remained independently associated with mortality were cavitation on chest x-ray (aHR = 7.92, 95% CI, 1.74-35.94, p = .0073) and LAM positivity (aHR = 5.53, 95% CI, 1.09-28.06, p = .0389). The only factor that remained significantly associated with severe morbidity was LAM positivity (aOR = 2.04, 95% CI, 1.06-3.92, p = .0323). No factor remained significantly associated with unsuccessful tuberculosis treatment. CONCLUSIONS: In PLWH with tuberculosis enrolled in a trial, tuberculosis disease characteristics related to disease severity were cavitation on chest x-ray and urine LAM positivity. Early identification of these factors could help improve the management of PLWH with tuberculosis and improve their survival
Lissamphibiens de Dams (Quercy, SO France): Identification taxonomique et evolution durant la transition Eocene-Oligocene
No full textInternational audienceThe locality of Dams (Quercy, southwestern France) has yielded two fossil assemblages, one from the late Eocene and another from the early Oligocene, making it one of the few localities with infillings across the Eocene-Oligocene transition. At least 24 taxa (13 mammals, 11 snakes) have been identified in this locality. Study of the lissamphibian remains from Dams yields an Eocene and an Oligocene assemblage, with a total of eight taxa. The Eocene assemblage includes two unnamed salamandrine species, one unnamed pelobatid species and one pyxicephalid species (Thaumastosaurus). The Oligocene assemblage includes two unnamed pleurodeline species, one salamandrine species (Salamandra sansaniensis) and an unnamed pelobatid species. Among the eight taxa from Dams, one Eocene salamandrine and one Oligocene pleurodeline are identified for the first time in the Quercy. A review of the lissamphibians from the Quercy area identifies eleven taxa for the Late Eocene (MP19) and eight taxa for Early Oligocene (MP22), with a major turnover at the Eocene-Oligocene transition. This turnover occurs in a time of major climatic changes, with a significant decrease in temperature and precipitation and concurrent increase in seasonality in Europe, likely affecting specialized taxa
PFMG2025–integrating genomic medicine into the national healthcare system in France
No full textInternational audienceIntegrating genomic medicine into healthcare systems is a health policy challenge that requires continuously transferring scientific advances into clinics and ensuring equal access for patients. France was one of the first countries to integrate genome sequencing into clinical practice at a nationwide level, with the ambition to provide more accurate diagnostics and personalized treatments. Since 2016, the French government has invested €239M in the 2025 French Genomic Medicine Initiative (PFMG2025) which has so far focused on patients with rare diseases (RD), cancer genetic predisposition (CGP) and cancers. PFMG2025 has addressed numerous challenges to set up an operational organizational framework. As of December the 31st 2023, 12,737 results were returned to prescribers for RD/CGP patients (median delivery time: 202 days, diagnostic yield: 30.6%) and 3109 for cancer patients (median delivery time: 45 days). PFMG2025's future priorities encompass ensuring economic sustainability, strengthening links with research, empowering patients and practitioners, and fostering collaborations with European partners.Funding As of December the 31st 2023, €239M have been invested by the French government.</div
Large-scale palaeoflow at the top of Earth's core
No full textInternational audienceA number of recent studies have made use of statistics derived from geodynamo simulations to constrain the flow at the top of the Earth's core. Here we adapt these methods to infer possible core surface flow solutions over the past 9000 years, using a low degree geomagnetic field model, based on archaeomagnetic and sedimentary archives. Despite the low spatial resolution of the field model, we find that the largest scale aspects of the recovered flow agree well with those derived from historical field models. In particular we see the growth of an eccentric planetary gyre over the past 400 years and find that a similar feature appears on bimillennial timescales, concurrent with pulses in the zonal flow. In the flow model vigorous gyre structures are not persistent but appear as transient features with durations of a few hundred years. The zonal flow is westward over the entire period with a mean value of 0.09 • /yr. Finally, we consider the variations in length-of-day that are implied by the flow model under the assumption of geostrophy, and compare the total clock error with that inferred from records of historical solar eclipses. Good agreement is found between the two series of mantle rotation for at least the past 1200 years, with anomalously slow mantle rotation coupled with reduced westward zonal flow. Further back in time a rigorous assessment is hard to make, owing to uncertainty surrounding the exact locations of eclipses.</div