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Valoriser les services rendus par la prairie. Une voie pour assurer la durabilité des systèmes d’élevage herbagers ?
No full textConception of local carbon markets connecting farmers and companies: socio-economic outlines of innovative devices
No full textConception of local carbon markets connecting farmers and companies: socio-economic outlines of innovative devices
Les applications antibactériennes des bactériophages
No full textDès 1917, dans l’article où il décrit ses premières observations et propose le nom de bactériophage, Félix d’Hérelle rapporte une première utilisation de ces virus pour traiter des infections bactériennes, donnant ainsi naissance à la phagothérapie. Le développement de cette application a montré qu’il était possible de mettre en place des traitements ciblant spécifiquement les bactéries, tels que ceux basés sur l’utilisation d’antibiotiques. Ces derniers, de par leur très grande efficacité et simplicité d’utilisation, ont provoqué le quasi-abandon de la phagothérapie. Aujourd’hui, un nombre croissant de bactéries pathogènes pour l’homme présente des phénotypes de résistance à plusieurs familles d’antibiotiques. Les infections causées par ces bactéries imposent l’utilisation de molécules au spectre d’activité toujours plus large et placent certains patients en situation d’impasse thérapeutique. Cet état de fait a relancé les recherches pour permettre le déploiement de la phagothérapie afin de traiter des patients mais aussi des animaux et des plantes. En fait, les domaines d’applications thérapeutiques des bactériophages s’élargissent au fur et à mesure que les agents antibactériens de nature chimique sont remis en cause, voire interdits. Cette revue revient sur les principes fondamentaux des applications thérapeutiques des bactériophages et expose les données récentes dans les domaines pour lesquels une exploitation commerciale est en cours ou sur le point d’émerger.In the 1917 article in which Félix d'Hérelle describes his first observations and proposes the name of bacteriophage, he also reports the first use of these viruses to treat bacterial infections, thus giving birth to phage therapy. Soon after antibiotics supplanted bacteriophages. Today, bacteria resistant to multiple antibiotics become a growing public health issue worldwide. This situation has revived research aiming at developing the antibacterial activity of bacteriophages to treat patients as well as diseases in animals and plants. In fact, the areas of applications of bacteriophages as antibacterial are widening as current solutions of chemical nature are questioned. This review summarizes the basic principles of therapeutic applications of bacteriophages and presents recent data in areas where commercial exploitation is occurring or about to emerge
Marchés, compétitivité coût et hors coût des filières : quelques considérations sur les productions animales en France et dans l’UE
No full textMarchés, compétitivité coût et hors coût des filières : quelques considérations sur les productions animales en France et dans l’U
The Analysis of the Editing Defects in the dyw2 Mutant Provides New Clues for the Prediction of RNA Targets of Arabidopsis E+-Class PPR Proteins
No full textC to U editing is one of the post-transcriptional steps which are required for the proper expression of chloroplast and mitochondrial genes in plants. It depends on several proteins acting together which include the PLS-class pentatricopeptide repeat proteins (PPR). DYW2 was recently shown to be required for the editing of many sites in both organelles. In particular almost all the sites associated with the E+ subfamily of PPR proteins are depending on DYW2, suggesting that DYW2 is required for the function of E+-type PPR proteins. Here we strengthened this link by identifying 16 major editing sites controlled by 3 PPR proteins: OTP90, a DYW-type PPR and PGN and MEF37, 2 E+-type PPR proteins. A re-analysis of the DYW2 editotype showed that the 49 sites known to be associated with the 18 characterized E+-type PPR proteins all depend on DYW2. Considering only the 288 DYW2-dependent editing sites as potential E+-type PPR sites, instead of the 795 known editing sites, improves the performances of binding predictions systems based on the PPR code for E+-type PPR proteins. However, it does not compensate for poor binding predictions
Economic and environmental benefits from crop-livestock complementarities through local legume production: a modelling approach for western France
No full textThis Ph.D. thesis studies crop-livestock complementarities enabled by legumes in the region of western France. Economic and environmental assessment of these complementarities is performed from the farm scale to the regional scale.
The main contribution of this research is the development of the bio-economic model SYNERGY, which represents local exchanges of crops (including legumes) and manure between crop-oriented farms and livestock-oriented farms. This model represents the pre-crop effect of legumes and includes alternative rations with these high-protein crops. The main simulation results show that coupled subsidies to legumes
increase their production but do not lead to better valuation of technical complementarities. One way to increase the use of legumes in animal feed is to label GMO-free animal products. However, since the simulated local exchanges of legumes remain low, these crops are largely imported from outside the region. Thus, the economic and environmental results do not improve at the regional scale, and protein self-sufficiency decreases.
Finally, at the scale of the agro-food chain, exchanges of legumes lead to high transaction costs, which current contracts reduce only slightly. Developing markets that value local resources could foster legume production.Cette thèse de doctorat porte sur les complémentarités culture-élevage permises par les légumineuses, dans la région de l'Ouest de la France. Une évaluation économique et environnementale de ces complémentarités est réalisée depuis l’échelle de l’exploitation agricole jusqu’à celle de la région.
Le principal apport de cette thèse est l’élaboration d’un modèle bioéconomique SYNERGY qui modélise les échanges locaux de cultures (dont les légumineuses) et d’effluents entre des exploitations de grandes cultures et des exploitations d'élevage. Ce modèle prend en compte l’effet précédent des légumineuses et comprend des rations alternatives avec ces cultures riches en protéines. Les principaux résultats de simulation montrent que les aides couplées aux légumineuses accroissent leur
production mais n’engendrent pas une meilleure valorisation des complémentarités techniques. Un moyen d’accroître l'utilisation de légumineuses en alimentation animale est de labelliser les produits animaux sans OGM. Cependant, les échanges locaux simulés restant faibles, les légumineuses sont en grande partie importées de l’extérieur de la région. Ainsi, les résultats économiques et environnementaux ne sont pas améliorés à l’échelle régionale et l'autonomie en protéines diminue.
Enfin, à l’échelle des filières, nous montrons que les échanges de légumineuses engendrent des coûts de transaction élevés, peu réduits par les contrats existants. Le développement de marchés valorisant les ressources locales pourrait encourager la culture de légumineuses
Characterising ecological interaction networks to support risk assessment in classical biological control of weeds
No full textA key element in weed biological control is the selection of a biological control agent that minimizes
the risks of non-target attack and indirect effects on the recipient community. Network ecology is a
promising approach that could help decipher tritrophic interactions in both the native and the invaded
ranges, to complement quarantine-based host-specificity tests and gain insights on potential interactions
of biological control agents. This review highlights practical questions addressed by networks, including
1) biological control agent selection, based on specialization indices, 2) risk assessment of biological
control agent release into a novel environment, via particular patterns of association such as apparent
competition between agent(s) and native herbivore(s), 3) network comparisons through structural
metrics, 4) potential of network modelling and 5) limits of network construction method
A new tool for multi-block PLS discriminant analysis: application to metabolomic data in systems epidemiology
No full textDietary exposure to pesticide residues and associated health risks in infants and young children – Results of the French infant total diet study
No full textA total diet study (TDS) was undertaken to estimate the chronic dietary exposure to pesticide residues and health risks for the French infants and young children below 3 years old. As a whole, 516 pesticides and metabolites were analysed in 309 food composite samples including 219 manufactured baby foods and 90 common foods, which cover 97% of infants and young children's diet. These composite samples were prepared using 5,484 food products purchased during all seasons from 2011 to 2012 and processed as consumed. Pesticide residues were detected in 67% of the samples and quantified in 27% of the baby food samples and in 60% of the common foods. Seventy-eight different pesticides were detected and 37 of these quantified at levels ranging from 0.02 to 594 µg/kg. The most frequently detected pesticides (greater than 5% samples) were (1) the fungicides 2-phenylphenol, azoxystrobin, boscalid, captan and its metabolite tetrahydrophthalimide, carbendazim, cyprodinil, difenoconazole, dodine, imazalil, metalaxyl, tebuconazole, thiabendazole, (2) the insecticides acetamiprid, pirimiphos-methyl and thiacloprid, (3) the herbicide metribuzin and (4) the synergist piperonyl butoxide. Dietary intakes were estimated for each of the 705 individuals studied and for 431 pesticides incl. 281 with a toxicological reference value (TRV). In the lower-bound scenario, which tends to underestimate the exposure, the TRV were never exceeded. In the upper-bound scenario that overestimates exposure, the estimated intakes exceeded the TRV for dieldrin and lindane (two persistent organic pollutants) and propylene thiourea, a metabolite of propineb. For these three substances, more sensitive analyses are needed to refine the assessment. For 17 other detected and/or prioritised pesticides, the risk could not be characterised due to the lack of a valid TRV, of certain food analyses or the absence of analytical standards for their metabolites
Whole-genome sequencing confirms the coexistence of different colonizing Group B Streptococcus isolates underscored by CRISPR typing
No full textStreptococcus agalactiae is a major pathogen and is the leading cause of neonatal infections in industrialized countries. The diversity of strains isolated from two pregnant women was investigated. Here, we present the draft genome sequences of strains W8A2, W8A6, W10E2, and W10F3, obtained in order to ascertain their hylogenetic affiliation