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Reconstructed global monthly burned area maps from 1901 to 2020
No full textInternational audienceFire is a key Earth system process, driving variability in the global carbon cycle through CO2 emissions into the atmosphere and subsequent CO2 uptake through vegetation recovery after fires. Global spatiotemporally consistent datasets on burned area have been available since the beginning of the satellite era in the 1980s, but they are sparse prior to that date. In this study, we reconstructed global monthly burned area at a resolution of 0.5° × 0.5° from 1901 to 2020 using machine learning models trained on satellite-based observations of burned area between 2003 and 2020, with the goal of reconstructing long-term burned area information to constrain historical fire simulations. We first conducted a classification model to separate grid cells with extreme (burned area ≥ the 90th percentile in a given region) or regular fires. We then trained separate regression models for grid cells with extreme or regular fires. Both the classification and regression models were trained on a satellite-based burned area product (FireCCI51), using explanatory variables related to climate, vegetation and human activities. The trained models can well reproduce the long-term spatial patterns (slopes = 0.70–1.28 and R2 = 0.69–0.98 spatially), inter-annual variability and seasonality of the satellite-based burned area observations. After applying the trained model to the historical period, the predicted annual global total burned area ranges from 3.46×106 to 4.58×106 km2 yr−1 over 1901–2020 with regular and extreme fires accounting for 1.36×106–1.74×106 and 2.00×106–3.03×106 km2 yr−1, respectively. Our models estimate a global decrease in burned area during 1901–1978 (slope = -0.009×106 km2 yr−2), followed by an increase during 1978–2008 (slope = 0.020×106 km2 yr−2), and then a stronger decline in 2008–2020 (slope = -0.049×106 km2 yr−2). Africa was the continent with the largest burned area globally during 1901–2020, and its trends also dominated the global trends. We validated our predictions against charcoal records, and our product exhibits a high overall accuracy in simulating fire occurrence (>80 %) in boreal North America, southern Europe, South America, Africa and southeast Australia, but the overall accuracy is relatively lower in northern Europe and Asia (<50 %). In addition, we compared our burned area data with multiple independent regional burned area maps in Canada, the USA, Brazil, Chile and Europe, and found general consistency in the spatial patterns (linear regression slopes ranging 0.84–1.38 spatially) and the inter-annual variability. The global monthly 0.5° × 0.5° burned area fraction maps for 1901–2020 presented by this study can be downloaded for free from https://doi.org/10.5281/zenodo.14191467 (Guo and Li, 2024)
La part du genre, Genre et approche intersectionnelle dans les revues de sciences sociales françaises au XXIe
No full textGenre et approche intersectionnelle dans les revues de sciences sociales françaises au XXIe siècle RésuméQuand mobilise-t-on une perspective de genre dans les publications de sciences sociales françaises, et qui le fait ? Recourt-on davantage à cette approche que par le passé, et cette dernière en a-t-elle remplacé d'autres grilles d'analyse comme on l'entend parfois ? Parce qu'il est impossible de consulter l'ensemble de la production universitaire sur une longue période, les spéculations l'emportent souvent sur les analyses empiriques. Afin d'apporter une contribution à ces réflexions, ainsi qu'à l'histoire et à la sociologie des sciences sociales, cet article s'appuie sur des outils issus du traitement automatique des langues -des grands modèles de langage (LLMs) -pour repérer les invocations du genre dans un vaste corpus. Appliqué aux articles scientifiques de près de 120 revues de sciences sociales françaises publiées depuis le début du siècle, il offre plusieurs résultats parlants. Le recours à une approche de genre a indéniablement progressé au cours des vingt-cinq dernières années, même si le point de départ était souvent bas, et qu'il reste finalement limité. Des différences marquées existent entre disciplines, tout comme diffèrent les formes d'institutionnalisation de cette approche. Cette perspective est, en outre, encore très majoritairement mobilisée par des femmes. Enfin, l'approche intersectionnelle augmente légèrement, tout en restant très minoritaire, et sans que le genre ne se substitue à la classe.</div
Physiological responses to light regime of a Mediterranean lagoon strain of Chaetoceros tenuissimus and a collection strain of Chaetoceros calcitrans
No full textInternational audienceAbstract Diatoms play a fundamental ecological role as primary producers in aquatic food webs. Among these, a little number of solitary species of the genus Chaetoceros are of great interest as live food for aquaculture, including major taxa like Chaetoceros calcitrans which have been well studied in terms of growth and essential lipid content. In contrast, the globally distributed species Chaetoceros tenuissimus has not been investigated as a potential live prey for aquaculture. For a preliminary analysis of the effect of culture conditions on growth and biomass content of a new strain of C. tenuissimus (CT16ED, hereafter CTEN) isolated from a Mediterranean lagoon, we first considered the light regime, comparing cultivation under a light–dark (L:D) cycle (12:12 h L:D photoperiod) and under continuous light, which conditions were also applied to a C. calcitrans strain, CCAP1085/3 (CCAL). Both strains had a similar growth rate under continuous light, but growth rate was lower in CTEN than in CCAL under the L:D cycle. Photosynthetic pigments content was higher under the L:D cycle than under continuous light in both strains, and higher pigment content was found in CCAL than in CTEN, indicating different photoacclimation. The lipid content of CTEN did not change markedly with photoperiod or growth phase, unlike CCAL. Both strains had high proportions of essential lipids, particularly n-3 polyunsaturated fatty acids, including EPA and DHA, but these varied less in CTEN than in CCAL. CTEN was richer in DHA (22:6n-3) with a more balanced DHA:EPA ratio. From these results, a potential interest of CTEN for use in aquaculture is discussed, with regard to its nutritional quality (essential lipid content), its growth, and its high-light niche offering possibilities for cultivation in outdoor systems in the Mediterranean area
A French Multicenter Real-Life Study on the Biological and Clinical Parameters Associated With Response to Immune Checkpoint Inhibitors (ICIs) in Second-Line Treatment of Advanced Urothelial Carcinoma: Impact of Antibiotics Administration at the Time of ICIs Initiation
No full textInternational audienceBackground: After failure of first-line chemotherapy, standard of care for advanced urothelial cancer (aUC) is immune checkpoint inhibitors (ICIs) targeting PD-1/PD-L1 pathway. Several prognostic models (Bajorin and Bellmunt scores) have been evaluated, but only in the context of chemotherapy.Objective: To study whether the variables in these scores and new emerging clinical and biological criteria have an impact on the probability of objective response in aUC treated with ICIs in 2nd-line setting and beyond.Materials and methods: Between October 2016 and March 2023, we included 168 patients treated with ICIs in 2nd-line setting or more in 2 French centers. Variables of interest were selected after a literature review and collected retrospectively. Analyses used log-rank test and multivariate models (binary logistic and Cox regressions).Results and limitations: Median age at diagnosis was 68 years. Patients presented with bladder tumors in 73.8% and upper urinary tract tumors in 26.2%. 63.7% of patients had received only one line of chemotherapy before ICIs. Median follow-up after starting ICIs was 8.9 months. The variables statistically associated with objective response were: - The presence of locally advanced or lymph node-only disease compared with visceral involvement (adjusted Odds Ratio 0.19, 95% confidence interval [0.06-0.55], P = .002) and bone-only involvement (aOR 0.22 [0.08-0.64], P = .005) - The absence of antibiotic therapy the month before/after ICIs initiation (aOR 0.31 [0.12-0.84], P = .021). Limitations included retrospective design and small number of patients included.Conclusion: This real-life study from 2 French centers found a higher likelihood of objective response: - In the absence of antibiotic therapy at ICIs initiation: - In locally advanced or lymph node-only disease, in contrast to visceral or bone-only disease. Our results suggest that negative impact of antibiotic therapy on the response to ICIs needs to be further investigated to optimize the management of these patients
EtiquetteR
No full textEtiquetteR is an R package designed to streamline the creation of high-quality labels for insect pinning. By taking a dataset as input, EtiquetteR generates printable labels in PDF format, helping researchers and entomologists maintain accurate and standardized specimen records. For enhanced accessibility, the package includes a user-friendly Shiny application, InsectLabelR, which provides a graphical interface for generating labels without requiring programming expertise
The spatiotemporal ecology of Oropouche virus across Latin America: a multidisciplinary, laboratory-based, modelling study
No full textInternational audienceBackgroundLatin America has been experiencing an Oropouche virus (OROV) outbreak of unprecedented magnitude and spread since 2023–24 for unknown reasons. We aimed to identify risk predictors of and areas at risk for OROV transmission.MethodsIn this multidisciplinary, laboratory-based, modelling study, we retrospectively tested anonymised serum samples collected between 2001 and 2022 for studies on virus epidemiology and medical diagnostics in Bolivia, Brazil, Colombia, Costa Rica, Ecuador, and Peru with nucleoprotein-based commercial ELISAs for OROV-specific IgG and IgM antibodies. Serum samples positive for IgG from different ecological regions and sampling years were tested against Guaroa virus and two OROV glycoprotein reassortants (Iquitos virus and Madre de Dios virus) via plaque reduction neutralisation testing (PRNT) to validate IgG ELISA specificity and support antigenic cartography. Three OROV strains were included in the neutralisation testing, a Cuban OROV isolate from the 2023–24 outbreak, a contemporary Peruvian OROV isolate taken from a patient in 2020, and a historical OROV isolate from Brazil. We analysed the serological data alongside age, sex, cohort, and geographical residence data for the serum samples; reported OROV incidence data; and vector occurrence data to explore OROV transmission in ecologically different regions of Latin America. We used the MaxEnt machine learning methodology to spatially analyse and predict OROV infection risk across Latin America, fitting one model with presence–absence serological data (seropositive results were recorded as presence and seronegative results were recorded as absence) and one model with presence-only, reported incidence data from 2024. We computed marginal dependency plots, variable contribution, and permutation metrics to analyse the impact of socioecological predictors and fitted a generalised linear mixed-effects model with logit link and binary error structure to analyse the potential effects of age, sex, or cohort type bias and interactions between age or sex and cohort type in our serological data. We conducted antigenic cartography and evolutionary characterisations of all available genomic sequences for all three OROV genome segments from the National Center for Biotechnology Information, including branch-specific selection pressure analysis and the construction of OROV phylogenetic trees.FindingsIn total, 9420 serum samples were included in this study, representing 76 provinces in the six Latin American countries previously mentioned. The sex distribution across the combined cohorts was 48% female (4237 of 8910 samples with available data) and 52% male (4673 of 8910 samples) and the mean age was 29·5 years (range 0–95 years). The samples were collected from census-based cohorts, cohorts of healthy individuals, and cohorts of febrile patients receiving routine health care. The average OROV IgG antibody detection rate was 6·3% (95% CI 5·8–6·8), with substantial regional heterogeneity. The presence–absence, serology-based model predicted high-risk areas for OROV transmission in the Amazon River basin, around the coastal and southern areas of Brazil, and in parts of central America and the Caribbean islands, consistent with case data from the 2023–24 outbreak reported by the Pan American Health Organization. Areas with a high predicted risk of OROV transmission with the serology-based model showed a statistically significant positive correlation with state-level incidence rates per 100 000 people in 2024 (generalised linear model, p=0·0003). The area under the curve estimates were 0·79 (95% CI 0·78–0·80) for the serology-based model and 0·66 (95% CI 0·65–0·66) for the presence-only incidence-based model. Longitudinal diagnostic testing of serum samples from cohorts of febrile patients suggested constant circulation of OROV in endemic regions at varying intensity. Climate variables accounted for more than 60% of variable contribution in both the serology-based and incidence-based models. Antigenic cartography, evolutionary analyses, and in-vitro growth comparisons showed clear differentiation between OROV and its glycoprotein reassortants, but not between the three different OROV strains. PRNT titres of OROV-neutralising serum samples were strongly correlated between all three tested OROV isolates (r>0·83; p<0·0001) but were not correlated with the two glycoprotein reassortants.InterpretationOur data suggest that climatic factors are major drivers of OROV spread and were potentially exacerbated during 2024 by extreme weather events. OROV glycoprotein reassortants, but not individual OROV strains, probably have distinct antigenicity. Preparedness for OROV outbreaks requires enhanced diagnostics, surveillance, and vector control in current and future endemic areas, which could all be informed by the risk predictions presented in this Article
Perceptions and management of diabetes and obesity among people living with HIV in Côte d'Ivoire: a qualitative study
No full textInternational audienceINTRODUCTION: The prevalence of both type 2 diabetes mellitus (T2DM) and obesity is increasing among people living with HIV (PLHIV) in sub-Saharan Africa. We examined the perceptions and management of these two conditions among PLHIV and healthcare workers in Côte D'Ivoire. METHOD: From June to August 2022, we conducted semi-structured face-to-face interviews with PLHIV diagnosed with T2DM and/or obesity, as well as healthcare workers, in one of the major HIV clinics in Abidjan, Cote d'Ivoire. We explored topics such as experiences, perceptions and acceptability of the diagnosis and management of T2DM and obesity among PLHIV. Among healthcare workers, professional experience, professional relationships with patients diagnosed with T2DM/obesity, involvement in patient management and care provision were explored. Interviews were audio recorded and transcribed manually. Data were analysed using thematic analysis. RESULTS: A total of 15 PLHIV and 5 healthcare workers participated in semi-structured in-depth interviews. Perceptions towards T2DM and obesity were largely influenced by cultural factors, PLHIV reported negative perceptions of T2DM and positive perceptions of obesity. Both patients and healthcare providers considered the management of these conditions as sub-optimal. Patient-reported barriers to care for these metabolic disorders were mainly socio-economic and environmental, while healthcare workers emphasized patients' denial of their illness and the limited range of treatment options available at the clinic. CONCLUSION: These results highlight the complexity surrounding the perceptions and management of T2DM and obesity among PLHIV in Abidjan, Côte d'Ivoire. In order to implement innovative and efficient intervention strategies to prevent and treat these metabolic conditions, cultural beliefs as well as socio-economic barriers must be addressed
Morphology and phylogeny of Prorocentrum venetum Tolomio & Cavolo (Dinophyceae)
No full textInternational audienceProrocentrum venetum was one of the first species of the genus Prorocentrum described by scanning electron microscopy by Tolomio and Cavolo in 1985. Since the first observation of the species in the Venice Lagoon (Italy) in summer 1981, it has not been reported again in published phytoplankton records of Mediterranean waters or elsewhere. Two strains were isolated from a French Mediterranean lagoon, which were morphologically identified as P. venetum by microscopy. Based on rDNA sequences (spanning the 18S to the D3 region of 28S rDNA), the phylogenetic analysis demonstrated that P. venetum belongs to the same clade as Prorocentrum triestinum and Prorocentrum redfieldii. The analysis of scanning electron micrographs provided an in-depth morphological description of the theca, particularly on the pore pattern of thecal plates and new structural details of the platelets in the periflagellar area. These morphological characteristics were compared with the closely related species within the P. triestinum clade, which showed synapomorphic characters in the periflagellar area (small accessory pore, platelet pattern, shape of the apical wing). Further comparison of characteristics varying between species in this clade and in the sister clade encompassing species related to Prorocentrum micans suggests some features of morphological evolution within this part of the genus
L' Hypersensibilité chez les Hauts Potentiels Intellectuels (HPI) : mythe ou réalité ? Une revue systématique de la littérature
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Development of a Zebrafish Embryo‐Based Test System for Thyroid Hormone System Disruption: 3Rs in Ecotoxicological Research
No full textInternational audienceThere is increasing concern regarding pollutants disrupting the vertebrate thyroid hormone (TH) system, which is crucial for development. Thus, identification of TH system–disrupting chemicals (THSDCs) is an important requirement in the Organisation for Economic Co‐operation and Development (OECD) testing framework. The current OECD approach uses different model organisms for different endocrine modalities, leading to a high number of animal tests. Alternative models compatible with the 3Rs (replacement, reduction, refinement) principle are required. Zebrafish embryos, not protected by current European Union animal welfare legislation, represent a promising model. Studies show that zebrafish swim bladder inflation and eye development are affected by THSDCs, and the respective adverse outcome pathways (AOPs) have been established. The present study compared effects of four THSDCs with distinct molecular modes of action: Propylthiouracil (PTU), potassium perchlorate, iopanoic acid, and the TH triiodothyronine (T3) were tested with a protocol based on the OECD fish embryo toxicity test (FET). Effects were analyzed according to the AOP concept from molecular over morphological to behavioral levels: Analysis of thyroid‐ and eye‐related gene expression revealed significant effects after PTU and T3 exposure. All substances caused changes in thyroid follicle morphology of a transgenic zebrafish line expressing fluorescence in thyrocytes. Impaired eye development and swimming activity were observed in all treatments, supporting the hypothesis that THSDCs cause adverse population‐relevant changes. Findings thus confirm that the FET can be amended by TH system–related endpoints into an integrated protocol comprising molecular, morphological, and behavioral endpoints for environmental risk assessment of potential endocrine disruptors, which is compatible with the 3Rs principle. Environ Toxicol Chem 2024;00:1–18. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC