Archive Ouverte d'INRAE
Not a member yet
513551 research outputs found
Sort by
Phenogenomics reveals the ecology and evolution of Trichoderma fungi for sustainable agriculture
No full textInternational audienceTrichoderma fungi support sustainable agriculture by suppressing plant diseases and improving crop performance. However, emerging pathogenicity of Trichoderma warrants further ecological and genetic characterization. Here we used machine learning to correlate genomic data from 37 Trichoderma strains with over 140 phenotypic traits, spanning metabolic versatility, biotic interactions, stress tolerance and reproductive strategies. We determined Trichoderma to be an ancient, genetically cohesive and physiologically diverse genus with spores capable of germination in water and dispersal via air and water droplets. Metabolic preferences indicate universal adaptation to mycoparasitism and to niches like arboreal microbial mats, alongside broader saprotrophic versatility. Our analyses are consistent with character displacement among close relatives and convergent evolution in distant lineages, with both processes shaping ecological plasticity and traits including dispersal modes, terrestrialization or endophytism. Our findings reveal that while some Trichoderma species show traits of biosafety concern, its vast ecophysiological diversity enables the development of safe, targeted bioeffectors
Is Paris breathing? A scrutiny of the Paris thunderstorm asthma episode of June 2023
No full textInternational audienceAim: To describe the first major epidemic thunderstorm asthma (ETSA) event detected in France in June 2023. Methods: Data on local meteorology, visits to the emergency room (ER) for asthma and hospitalization after a visit, aerobiological composition of the atmosphere (pollens and spores), phenological information on the flowering of grasses, and regional air pollution were collected, aggregated, and analyzed.Results: The ETSA was centered on the Paris region. An excess of 1,900 emergency visits for asthma was recorded over the period 10, 11, and 12 June. The people most affected were men aged 14 to 44. The hospitalization rate following a visit to the ER for asthma increased to 13%. ER visits for asthma began at around 6 pm on 10 June, just after an intense gust (15 m/s) triggering a PM10 resuspension episode, and peaked at around 10 pm on 11 June. Concentrations of mold spores (Cladosporium and Ascosporium) rose sharply during the night of 10-11 June, at the same time as the intake peak. The ETSA occurred during the grass and Urticaceae pollen season, with pollen concentrations lower (< 100 pollen grains/m 3 ) compared to the days preceding the event (> 200 pollen grains/m 3 ). A fraction of the pollen was observed without cytoplasm, but there was no apparent link with the ETSA. Phenological observations in the Paris pollinarium showed that the ETSA coincided with the start of the Lolium perenne (ryegrass) pollen season.Conclusions: Although the data collected did not allow the identification of a single cause for the occurrence of the ETSA, they pointed to multifactorial causes such as the occurrence of an ozone pollution episode, strong winds before the storm, an episode of resuspension of PM10 particles, the presence of broken pollen, and the significant increase in mold spores just after the stormy episode
Mergers and investments : where do we stand ?
No full textNational audienceIn this paper, we review recent studies on the impact of mergers on investments. We begin by examining how mergers among competing incumbents inf luence firms’ incentives to develop new products and undertake cost-reducing or quality-enhancing investment. We then analyze how an incumbent’s acquisition of an innovative entrant affects the investment incentives of both parties. Next, we discuss the effects of vertical mergers on the investment decisions of both upstream and downstream firms. Finally, we highlight several policy-relevant insights from the literature and suggest directions for future research
Detection of antibiotic resistance gene mecA in foodborne Staphylococcus aureus with electrochemical biosensor
No full textInternational audienceThe increasing spread of antibiotic resistance and the transmission of antibiotic resistance genes require the urgent development of rapid and cost-effective detection methods. The food chain plays a significant role in the dissemination of resistant bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). In this study, MRSA were isolated from milk and meat. A DNA MECA probe specific to the mecA gene was designed, evaluated in silico for specificity and experimentally through dot blot hybridization using DNA from S. aureus isolates confirmed by PCR. The probe was then integrated into an electrochemical biosensor based on Screen Printed gold Electrodes. In the absence of the target gene, the current signal stayed above baseline, whereas the presence of mecA gene resulted in a concentration-dependent decrease in signal, indicating effective hybridization within the range of 10 fg/mu L - 1 ng/mu L. Scanning electron microscopy analysis confirmed the presence of biological material exclusively on functionalized working electrode exposed to mecA-positive DNA. The system was further tested on S. aureus DNA extracted from 13 raw milk and meat matrices, demonstrating the biosensor's applicability for rapid (20-min), easy-to-perform, and low-cost detection of mecA gene. This work provides a promising basis for the development of on-site screening tools to monitor AR in the food production chain
Unraveling viral identity: Avoiding the trap of endogenous sequences for viral surveillance of small ruminant oncogenic retroviruses
No full textSmall ruminants (sheep and goats) are one of the few mammals in which an exogenous retrovirus (XRV) and closely related endogenous retroviral elements(ERV) coexist within the same host genome. The betaretroviruses Jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV) cause pulmonary and nasal adenocarcinomas, respectively, and share extensive sequence similarity with their endogenous counterparts. Consequently, molecular surveillance must rely on assays that can unequivocally distinguish true exogenous infection from ERV‐derived templates; failure to do so compromises diagnosis, phylogenetic inference, and epidemiological conclusions. We retrieved all complete JSRV, ENTV-1/2, and related ERV genomes deposited in public repositories and performed a comprehensive alignment. Only a limited number of genomic segments were capable of distinguishing exogenous from endogenous sequences. We refer to these as discriminating regions (DRs). Phylogenies built using DRs revealed that several entries annotated as XRV are, in fact, ERV-derived or chimeric artefacts generated by short-amplicon reconstruction. A systematic literature review of over 100 articles identified 286 distinct primers and probes used for the XRV amplification. In-silico mapping of each oligonucleotide onto the full alignment showed that only 28 % reliably differentiate XRV from ERV. We experimentally validated the predictive power of this approach for 17 primer/probe sets, confirming that non-discriminating assays produce false-positive signals from endogenous templates. The misannotation of ERV sequences as exogenous viruses has resulting in the population of databases with dubious entries, fostering erroneous hypotheses such as vector-borne transmission of JSRV and ENTV. To address this issue, we propose a concise set of criteria for assay design, validation, and database annotation emphasizing DR targeting, specificity testing against endogenous templates, and transparent reporting. Although this framework was developed for small ruminants, it is readily applicable to any host–virus system in which exogenous viruses coexist with endogenous viral elements. This will strengthen viral surveillance, phylogenetics, and the One-Health initiatives
The Maize ZmbHLH118 Transcription Factor Regulates Vacuolar Nitrate Loading by the NO <sub>3</sub> <sup>−</sup> Transporter ZmCLCa
No full textInternational audienceNitrate (NO 3-) is a major nutrient promoting plant growth and crop yield. Vacuolar nitrate storage is essential for nitrate acquisition and remobilization within the plant. However, the transcriptional regulation of transporters facilitating nitrate influx into the vacuole remains unclear. Here, we identified a bHLH transcription factor, ZmbHLH118, that negatively regulates the expression of ZmCLCa , thereby modulating nitrate vacuolar loading and uptake in maize ( Zea mays ). ZmbHLH118 overexpression and ZmCLCa loss-of-function in maize impaired root NO 3 -uptake, and further reduced nitrate content and plant growth.Moreover, ZmbHLH118 directly binds to the promoter and inhibits the expression of ZmCLCa , which encodes a tonoplast-localized nitrate transporter. Electrophysiological analysis showed that ZmCLCa mediates NO 3 -fluxes across the vacuolar membrane, indicating that ZmCLCa-mediated NO 3 -influx is required for vacuolar nitrate storage. Our data identify the ZmbHLH118 as a molecular actor of the transcriptional regulation of ZmCLCa in response to extracellular nitrate. This provides insights into the regulatory mechanisms acting upstream of the CLCa-mediated vacuolar nitrate transport. Finally, field assays showed that the regulation mechanisms of vacuolar nitrate affect maize growth and grain yield, highlighting their value for nitrogen use efficiency improvement in crop plants
Attractor Basins in Concurrent Systems
No full textA crucial question in analyzing a concurrent system is to determine its longrun behaviour, and in particular, whether there are irreversible choices in its evolution, leading into parts of the reachability space from which there is no return to other parts. Casting this problem in the unifying framework of safe Petri nets, we have provided in previous work techniques for identifying attractors, i.e. terminal strongly connected components of the reachability space. Here, what we aim at is to determine the attraction basins associated to those attractors; that is, those states from where all infinite runs are doomed to end in the given attractor, as opposed to those that are free to evolve differently. Here, we provide a solution 1for the case of safe Petri nets. Our algorithm uses net unfoldings and provides a map of all of those configurations (concurrent executions of the system) that lead onto cliff-edges, i.e. any maximal extension for those configurations lies in some basin that is considered fatal
How ICT shapes wages, working conditions, and job satisfaction
No full textWe study how the widespread diffusion of ICT affects wages, working conditions, and job satisfaction. We frame our empirical investigation with a model in which ICT can improve both wages and working conditions by increasing firms' output. Using French matched employer-employee data and an instrumental variable approach that is motivated by the model, we find that ICT diffusion in 2013-2019 has been beneficial to workers, who experienced both higher wages and better working conditions, particularly through greater flexibility, physical comfort, and safety. In contrast, ICT use has also increased psychological stress and work intensity. These effects vary across workers, firms, occupations and sectors, depending on their characteristics. Despite overall improvements in wages and working conditions, we estimate only modest positive effects of ICT use on job satisfaction. We discuss potential explanations for this finding
Approche territoriale pour la prévention des risques en montagne, Proposition de cadre technique pour l’analyse et la gestion intégrée des risques naturels en montagne, Module X : Etapes administratives, techniques et suivi de la démarche globale STePRiM
No full textLa gestion intégrée des risques naturels en montagne est un concept visant à coconstruire des stratégies de réduction des risques dans le cadre d’approches territoriales multi-phénomènes. Pour accompagner ce type d’approche, des documents techniques ont été imaginés pour aider les opérateurs à réaliser ces étapes principales. Ce module est une contribution à la description globale d’une démarche STePRIM d’un point de vue technique, administratif et organisationnel. Il s’adresse donc principalement aux acteurs institutionnels intervenant dans une démarche STePRiM. Il en décrit les grands principes et étapes, propose des modes organisations opérationnels notamment en termes de pilotage. Son contenu n’est pas strictement technique. Ce document n’a aucun caractère prescriptif. Il ne constitue qu’une description de la démarche globale et une série de propositions d’organisation pour la mise en œuvre basée sur quelques expériences pratiques. Ce module propose une vision globale et pragmatique, testée lors de l’implémentation en conditions réelles d’approches de type STePRiM. Il synthétise plusieurs contributions faites en collaboration et à destination des collectivités impliquées dans la démarche dans des départements pilotes. A ce titre, il peut le cas échéant, servir à communiquer sur le dispositif ou suggérer des modes opératoires. Un point particulièrement notable concerne la formalisation, l’association et la juxtaposition d’approches de quantification du risque et d’aide à la décision