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Deep genetic divergence underlies within-island eco-morphological variation in the endangered day gecko Phelsuma borbonica: implications for conservation
No full textInternational audienc
Optimizing soil and plant functions: combinatory design of fertilizing resources assemblage for rainfed rice in Madagascar
No full textInternational audienceThe lack of affordable mineral fertilizers and scarcity of organic materials cause decline in soil fertility for smallholder farmers and producers in the highlands of Madagascar, challenging crop productivity. To fulfill plant growth and nutrition, we explored the effect of 132 combinations of 17 different fertilizing resources, both organic and mineral, on rice growth and nutrition using a greenhouse experiment. Two clustering approaches were used to evaluate the effects of fertilizing resources: elemental clustering and functional clustering. Elemental clustering grouped resources based on their elemental intrinsic composition, while functional clustering grouped resources based on their effect in improving plant growth and nutrition when combined in soil. We found that some resources closely grouped based on their elemental composition exhibited different effects on plant growth and nutrition when combined in soil. Zebu horn emerged as a particular organic resource in elemental clustering, and a key resource in functional clustering by promoting plant growth and nutrition when combined with other resources in soil. Its unique elemental composition played a significant role in driving positive interactions with other resources. We proposed to extend the concept of 'assembly motif' within soil fertilization strategy, suggesting that the combination of functional groups of resources determines better their fertilizing effect than their elemental composition. Resources inducing high interaction effects should be combined with those having high elemental composition to optimize crop productivity
Biogeography and ecology of the Algerian island flora
No full textInternational audienceBackground and aims – In spite of their proximity to the coasts, the flora of the islands and islets of the Algerian coasts has been poorly studied. This work is the first to provide an overall view of the richness and the determinants of the Algerian island flora. Material and methods – The study is based on a compilation of original floristic data. Two classifications of 30 islands and islets were derived from PCA and HCPC performed on the species occurrence matrix and on a matrix of flora descriptors including species richness, functional traits (life form, seed dispersal, pollination), and biogeographic range. We performed an RDA to explain the variation in flora characteristics by a set of physiographic (longitude, latitude, elevation, area, isolation, steepness index, and area/perimeter ratio) and biotic (seabird density and human presence) variables. Key results – The floristic inventory encompassed a total richness of 295 vascular plant taxa (including subspecies and varieties) on the 30 studied sites. Five main groups of islands and islets can be distinguished based on vegetation composition and three from flora descriptors. RDA model selection revealed that the combination of four variables (seabird density, area, latitude, and longitude) explained 26.6% of the variation in flora characteristics. Taken alone, the density of yellow-legged gull colonies and the island area were the main drivers of this variation. Results showed that floristic richness was associated with larger island area and higher seabird density, the importance of some plant functional traits, such as zoochory and entomogamy, and with a higher proportion of Eurasian holarctic species. Conclusion – In the context of island flora conservation, some of these small islands of Algeria can be considered as “modern refuges” from human pressures, and this is particularly important in the context of Mediterranean ecosystems characterised by a quasi-permanent human impact in various habitats. Two new important plant areas (IPAs) for Algeria are proposed following the results of these floristic inventories
Integrated surveillance systems for antibiotic resistance in a One Health context: a scoping review
No full textInternational audienceBackground Antibiotic resistance (ABR) has emerged as a major threat to health. Properly informed decisions to mitigate this threat require surveillance systems that integrate information on resistant bacteria and antibiotic use in humans, animals, and the environment, in line with the One Health concept. Despite a strong call for the implementation of such integrated surveillance systems, we still lack a comprehensive overview of existing organizational models for integrated surveillance of ABR. To address this gap, we conducted a scoping review to characterize existing integrated surveillance systems for ABR. Methods The literature review was conducted using the PRISMA guidelines. The selected integrated surveillance systems were assessed according to 39 variables related to their organization and functioning, the socio-economic and political characteristics of their implementation context, and the levels of integration reached, together with their related outcomes. We conducted two distinct, complementary analyses on the data extracted: a descriptive analysis to summarize the characteristics of the integrated surveillance systems, and a multiple-correspondence analysis (MCA) followed by a hierarchical cluster analysis (HCA) to identify potential typology for surveillance systems. Results The literature search identified a total of 1330 records. After the screening phase, 59 references were kept from which 14 integrated surveillance systems were identified. They all operate in high-income countries and vary in terms of integration, both at informational and structural levels. The different systems combine information from a wide range of populations and commodities -in the human, animal and environmental domains, collection points, drug-bacterium pairs, and rely on various diagnostic and surveillance strategies. A variable level of collaboration was found for the governance and/or operation of the surveillance activities. The outcomes of integration are poorly described and evidenced. The 14 surveillance systems can be grouped into four distinct clusters, characterized by integration level in the two dimensions. The level of resources and regulatory framework in place appeared to play a major role in the establishment and organization of integrated surveillance. Conclusions This study suggests that operationalization of integrated surveillance for ABR is still not well established at a global scale, especially in low and middle-income countries and that the surveillance scope is not broad enough to obtain a comprehensive understanding of the complex dynamics of ABR to appropriately inform mitigation measures. Further studies are needed to better characterize the various integration models for surveillance with regard to their implementation context and evaluate the outcome of these models
Impacts of repetitive droughts and the key role of experience : evidence from Nigeria
No full textWestern African Sahel faced severe droughts in the 1980s, affecting agricultural production and food security. In recent decades, farmers have faced uncertainty in the timing and amount of rainy seasons and are confronted with erratic rainfall with high interannual variations. Can the experience of past dry events reduce the vulnerability of households to short-term rainfall shocks? In this paper, I match three waves of panel household surveys focusing on agriculture in Nigeria (GHS, from 2010-2016) and high temporal resolution precipitation data set from the Climate Hazard Center (CHIRPS). I show evidence of the extreme importance of the long-dry period of the 1980s and identify more recent droughts in 2013/2015, which are in line with a change in the characteristics of the rainfall trends. Through a two-way-fixed effect strategy, I exploit the spatial variation of the exposition to the 2015 drought. First, I look at the short-term effects of being hit by a drought on agricultural production and food security indicators. I show that being hit by a drought decreases yields by 14%, and decreases the food diversity of households by around 1%. Second, I look at the impacts' heterogeneity according to the plot's experience, using the timing of the year of acquisition of the plot. I compare short-term droughts' effects on households that acquired their first plot before the 1980s dry period to those that acquired it after. Results suggest that acquiring the land before 1985 attenuates the harmful effects of a climate shock, as these particular households have only a 3% reduction in their yields due to the 2015 drought. This is especially the case when households were severely hit in the 1980s. This result might suggest that having a long-lasting experience under extreme dry events on cultivated land reduces vulnerability to rainfall variability
General and abdominal adiposity and hypertension in eight world regions: a pooled analysis of 837 population-based studies with 7·5 million participants
No full textInternational audienceSummaryBackground Adiposity can be measured using BMI (which is based on weight and height) as well as indices of abdominal adiposity. We examined the association between BMI and waist-to-height ratio (WHtR) within and across populations of different world regions and quantified how well these two metrics discriminate between people with and without hypertension.MethodsWe used data from studies carried out from 1990 to 2023 on BMI, WHtR and hypertension in people aged 20–64 years in representative samples of the general population in eight world regions. We graphically compared the regional distributions of BMI and WHtR, and calculated Pearson’s correlation coefficients between BMI and WHtR within each region. We used mixed-effects linear regression to estimate the extent to which WHtR varies across regions at the same BMI. We graphically examined the prevalence of hypertension and the distribution of people who have hypertension both in relation to BMI and WHtR, and we assessed how closely BMI and WHtR discriminate between participants with and without hypertension using C-statistic and net reclassification improvement (NRI).FindingsThe correlation between BMI and WHtR ranged from 0·76 to 0·89 within different regions. After adjusting for age and BMI, mean WHtR was highest in south Asia for both sexes, followed by Latin America and the Caribbean and the region of central Asia, Middle East and north Africa. Mean WHtR was lowest in central and eastern Europe for both sexes, in the high-income western region for women, and in Oceania for men. Conversely, to achieve an equivalent WHtR, the BMI of the population of south Asia would need to be, on average, 2·79 kg/m² (95% CI 2·31–3·28) lower for women and 1·28 kg/m² (1·02–1·54) lower for men than in the high-income western region. In every region, hypertension prevalence increased with both BMI and WHtR. Models with either of these two adiposity metrics had virtually identical C-statistics and NRIs for every region and sex, with C-statistics ranging from 0·72 to 0·81 and NRIs ranging from 0·34 to 0·57 in different region and sex combinations. When both BMI and WHtR were used, performance improved only slightly compared with using either adiposity measure alone.InterpretationBMI can distinguish young and middle-aged adults with higher versus lower amounts of abdominal adiposity with moderate-to-high accuracy, and both BMI and WHtR distinguish people with or without hypertension. However, at the same BMI level, people in south Asia, Latin America and the Caribbean, and the region of central Asia, Middle East and north Africa, have higher WHtR than in the other regions
Le PGD d'entité au service d'une politique des données : Retour d'expérience d'AgroParisTech
No full textNational audienceLes plans de gestion de données pour les projets de recherche ont commencé à apparaître en 2017, avec le projet pilote d’Horizon 2020. Le PGD est ensuite devenu peu à peu un incontournable en France avec sa systématisation pour tous les projets ANR depuis 2019 et la nomination d’un référent qualité au niveau national. À la faveur de cette nouveauté, s’est ensuite posée la question d’une rationalisation des pratiques au niveau des unités de recherche et des plateformes : la réflexion sur le PGD d’entité de recherche démarrait. Formaliser la politique de données d’une entité, faciliter la rédaction des PGD de projet pour les chercheurs utilisant des données issues de plateformes, asseoir et valoriser des processus de qualité ; les PGD d’entités permettent de remplir de multiples objectifs
AgroParisTech : retour sur trois ans d’accompagnement à la gestion et l’ouverture des données de la recherche
No full textNational audienceAgroParisTech a mis en place sa politique d’établissement sur la gestion et l’ouverture des données de la recherche le 1er janvier 2021. Afin d’accompagner sa communauté de recherche et d’étudiants, des actions de formation ont été mises en place ainsi que des supports (fiches pratiques et logigramme) à disposition de tous. Une cellule « Données de la Recherche » a été créée ainsi qu’un réseau de référents dans les unités pour répondre aux besoins et interrogations de la communauté sur tous les sujets liés aux données. Nous proposons un panorama ainsi qu’un retour d’expérience sur ces actions
Espèces interceptées, introduites et invasives
No full textNational audienceLes auteurs de ce catalogue ont pour ambition en dirigeant la réalisation du catalogue de réunir la précision des éléments systématiques et taxonomiques du “Catalogue of Palaearctic Coleoptera”, et la pertinence des informations afférant à la distribution des espèces telles qu’avait su l’utiliser Jean Sainte-Claire Deville, mais aussi enrichir l’ouvrage par des informations sur la biologie des espèces. Enfin, leur objectif est de faire en sorte que l’ouvrage ne glisse pas vers l’obsolescence en le mettant à jour en ligne selon une périodicité qu'ils souhaitent régulière
Temporal dynamic of soil microbial communities and antibiotic resistance markers exposed to increasing concentrations of sulfamethoxazole
No full textInternational audienceThe reuse of treated wastewater (TWW) for irrigation is widely applied to alleviate pressure on freshwater resources. However, TWW contains antibiotics that once in soils, can exert selective pressure, promoting the emergence and spread of antimicrobial resistance (AMR) in the environment. Current environmental risk assessments for antibiotic residues rely on indicators such as Predicted No Effect Concentrations (PNECs), usually determined in liquid media. These PNECs aim to predict antibiotic concentrations that may promote resistance in the environment. Given the complexity of soil matrices, few studies have established PNEC values for soil, which likely differ significantly from aquatic environments.To address this gap, we developed a simplified experimental model using soil microcosms irrigated with TWW and the antibiotic sulfamethoxazole (SMX) to estimate threshold concentrations favouring resistance transfer or/and emergence within the soil microbiome. We identified SMX concentrations between 0.01 and 0.1 mg/kgdry soil that likely increased the abundance of sulfonamide resistance genes in soil. A time window of 1 to 7 days post-exposure showed a temporary rise in sul1 and intl1 gene abundance (over 1 log/soil 16S rDNA), the appearance of SMX transformation products, and an increase in some Rhodocyclaceae. After 1.5 months of incubation and complete SMX transformation, the relative abundance of sul1 and intl1 remained about 0.5 log higher than in SMX-free controls and soils with SMX levels below 0.1 mg/kg dry soil. A persistent transformation product, 4-N-glucuronide-SMX, was also observed.Here, the estimated PNEC for SMX in soil, between 0.01 and 0.1 mg/kg, exceeds typical SMX concentrations found in soils exposed to TWW. This may suggest low impact on resistance selection for this compound in the context of TWW exposure. However further studies on other soils, water, and antibiotics need to be conducted to expand our knowledge on soil PNECs