Etude de faisabilite d'un processeur materiel specialise pour la simulation concurrente de fautes

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Détection électrique d'anticorps sériques humains à l'aide d'un nanocapteur

LILLE1-BU (590092102) / SudocSudocFranceF

Modélisation et analyse spatiales des pratiques de mobilité partagée et de transport flexible en région PACA

En France métropolitaine, en 2018, on estime que les transports contribuent à environ 40 % dans l'émission du dioxyde de carbone atmosphérique, et consomment un tiers de l'énergie produite (ADEME, 2018). L'objectif de neutralité carbone fixé par l'État vise une réduction de 40 % des gaz à effet de serre dès 2030, puis 75 % à l'horizon 2075. Dans ce contexte, la région PACA a réduit de 22 % ses émissions entre 2000 et 2017, pour une baisse moyenne de 30 % au niveau de la France sur la même période. Face aux enjeux environnementaux, la région PACA, comme la plupart des régions françaises, se doit de réduire drastiquement ses émissions de polluants atmosphériques liés aux transports routiers. En complément du développement des transports publics, la lutte contre l'usage et la dépendance à l'automobile est l'une des voies possibles. Au-delà de mesures coercitives pour réduire la circulation en fonction des pics de pollution et une politique volontariste de sensibilisation de la population pour changer le rapport à l'automobile personnelle, on peut travailler sur le changement de pratiques en lien avec la progression des modes de transport alternatifs, dont notamment les transports flexibles et partagés. Dans notre étude, l'objectif environnemental est structurant, puisqu'il éclaire la façon dont nous allons analyser différents modes de transport de ce domaine, à savoir les véhicules autonomes, les transports à la demande, les véhicules de tourisme avec chauffeur, l'autopartage et le covoiturage. En effet, nous cherchons, à travers l'étude de leur efficacité en termes de regroupement et de réduction des kilomètres parcourus, à mettre en évidence leur capacité à réduire les émissions et ainsi à participer à la lutte contre le réchauffement climatique, tout en permettant une desserte optimisée et équitable des territoires. A ce titre, hormis l’analyse particulière des véhicules autonomes, largement tournés vers les nouvelles technologies connectées et l’intelligence artificielle, les thèmes abordés sont davantage en phase avec les scénarios « Bas carbone » et « Proximité » élaborés par la mission prospective de la région Provence Alpes Côte d’Azur. En effet, la mission Prospective a échafaudé des scénarios prospectifs aux horizons 2030 et 2050, sur la base de différentes expertises, dont le programme "la fabrique de connaissances" est une composante dans laquelle s'insère ce travail. Du point de vue scientifique, on notera deux éléments saillants dans cette étude : la comparaison des différents modes de transport flexible et partagé du point de vue environnemental et l’adaptation du modèle gravitaire de Wilson (ajout des exposants sur les populations et la distance, réduction de l’effet de la distance) pour l’estimation des flux

Genetic variability for key biomarkers involved in body reserves dynamics in meat ewes

International audienceThe use and accretion of body reserves (BR) is a biological mechanism in ruminants to cope with negative energybalance and improve animals’ adaptation. The aim of the present study was to understand the genetic backgroundof BR dynamics using plasma biomarker profiles (NEFA, non-esterified fatty acids; BHB, β-hydroxybutyrate;T3, triiodothyronine; INS, insulin) in Romane ewes reared under two contrasting farming systems (FS; indoor,IND, n = 173; extensive, OUT, n = 486). Primiparous and multiparous ewes were monitored at three to five keyphysiological stages (PhySt: mating, M; mid-pregnancy, P; 2 weeks pre-lambing; bL; 3 weeks post-lambing; aL;weaning; W). The co(variance) components were estimated with the AIREML method with a repeatability animalmodel in the BLUPF90+ family. Parity, cohort, line for feed efficiency, litter size, and FS were fixed effects, whileewe, the permanent environment of the ewes, and residuals were random effects. Heritabilities for NEFA, BHB,T3, and INS ranged from 0.12 to 0.30, 0.07 to 0.14, 0.17 to 0.26, and 0.05 to 0.32, respectively, depending onPhySt (standard errors, SE 0.03 to 0.04). Genetic correlations between the PhySt ranged from 0.07 to 0.86, 0.41 to0.9, 0.44 to 0.86, and -0.06 to 0.94 for NEFA, BHB, T3, and INS, respectively (SE, 0.06 to 0.14). Further analysesare in progress to estimate genetic correlations between biomarkers and identify associated QTL. In conclusion,genetic levers could be used to improve the adaptation of ruminants through BR dynamics. [Funding with iSAGEproject 679302

Evaluation of the Links between Lamb Feed Efficiency and Rumen and Plasma Metabolomic Data

Feed efficiency is one of the keystones that could help make animal production less costly and more environmentally friendly. Residual feed intake (RFI) is a widely used criterion to measure feed efficiency by regressing intake on the main energy sinks. We investigated rumen and plasma metabolomic data on Romane male lambs that had been genetically selected for either feed efficiency (line rfi−) or inefficiency (line rfi+). These investigations were conducted both during the growth phase under a 100% concentrate diet and later on under a mixed diet to identify differential metabolite expression and to link it to biological phenomena that could explain differences in feed efficiency. Nuclear magnetic resonance (NMR) data were analyzed using partial least squares discriminant analysis (PLS-DA), and correlations between metabolites’ relative concentrations were estimated to identify relationships between them. High levels of plasma citrate and malate were associated with genetically efficient animals, while high levels of amino acids such as L-threonine, L-serine, and L-leucine as well as beta-hydroxyisovalerate were associated with genetically inefficient animals under both diets. The two divergent lines could not be discriminated using rumen metabolites. Based on phenotypic residual feed intake (RFI), efficient and inefficient animals were discriminated using plasma metabolites determined under a 100% concentrate diet, but no discrimination was observed with plasma metabolites under a mixed diet or with rumen metabolites regardless of diet. Plasma amino acids, citrate, and malate were the most discriminant metabolites, suggesting that protein turnover and the mitochondrial production of energy could be the main phenomena that differ between efficient and inefficient Romane lambs

Individual variability in trajectories of key plasma biomarkers involved in body reserves dynamics inmeat ewes

International audienceThe mobilization and accretion of body reserves (BR) constitute one of the key mechanisms in ruminants for resilience and adaptation. A better understanding of inter-individual variability for candidate proxies of such mechanism is required before their use in breeding strategies. Primiparous and multiparous ewes were monitored during successive productive cycles in two contrasting farming systems (FS, indoor vs extensive) at five key physiological stages (Mating; mid-Pregnancy; 2 weeks Pre-Lambing; 3 weeks Post-Lambing; Weaning) for plasma biomarkers (NEFA, non-esterified fatty acids; BHB, β-hydroxybutyrate; T3, Triiodothyronine; INS, insulin). Unsupervised cluster analysis was done to investigate the variability in BR biomarkers trajectories. Overall mean trajectories for biomarkers followed BR dynamics throughout cycles and were mainly characterized by increases and decreases in NEFA, BHB, T3 and INS levels during BR mobilization and accretion phases, respectively. For each biomarker, two to three clusters of ewes were found depending on the parity and/or the FS. Trajectories between clusters differed in the levels and/or the shape. One of the major discrepancies between clusters was levels and/or time point when peaks of biomarkers were observed during BR mobilization. Higher individual variability in biomarkers was thus particularly observed around lambing. Genetic contribution in such variability for BR biomarkers was also investigated before considering these traits for breeding purpose. [Funding with H2020 iSAGE project 679302]

Are early-life lambs’ characteristics and behavioural reactivity related to later survival and growth performance during artificial feeding?

International audienceThe use of prolific sheep breeds often leads farmers to rear some lambs with an automatic milk feeder to improve survival and growth. However, the success of these challenging situations could depend on lamb's early individual characteristics, and their behavioural reactivity in a stressful context. The study was performed on 567 Romane lambs. We tested the hypothesis that early-life characteristics, including behaviour and physiology, could predict survival and growth performances until weaning. In addition, on a random subsample of one third of these lambs we assessed whether behavioural reactivity to social isolation and unknown human presence was a further predictor of individual variability in growth rate. Lambs were characterised by birth weight, rectal temperature and scores for vigour, handling and sucking of first bottle milk on arrival at nursing. After three weeks of artificial rearing (i.e. halfway to weaning age), 202 randomly-chosen lambs were studied in a 2-phase test to record their reaction to social isolation in a novel arena test and presence of an unknown human. Test variables were summarised phase-wise by principal component analysis. The factor scores characterised lamb general activity in phase 1 and affinity to humans in phase 2. Data was examined using descriptive statistics, survival analysis and multivariate regression models to identify the key factors for survival and average daily gain (ADG) until weaning. Cumulative early death rate at one week was 5% and global death rate at the end of the rearing period was 11.6%. There was a higher hazard ratio for death for weak sucking at the first milk-bottle test (P = 0.011), low rectal temperature (P < 0.05), and dam age of 4-5 years versus 2-3 years (P < 0.01). A low ADG until weaning was associated with a low vigour score (P < 0.01), weak sucking (P < 0.05) and low birth weight (P < 0.001). Our data also supports the hypothesis of a relationship between growth and behavioural reactivity in artificially-reared lambs. A low growth rate until weaning was also associated with higher lamb affinity shown to humans (P < 0.001) and lower activity expressed in social isolation in a new arena (P < 0.05). Our study suggests that early-age characteristics but also reactivity to social isolation and affinity to humans could be valuable predictors of lamb survival and growth in artificial rearing. Our results possibly reveal an overdependency on humans in some lambs in such a system

Body reserve dynamics using metabolites and hormones profiles of Romane ewes in two farming systems

The objective was to monitor the main effects affecting body reserve (BR) mobilization and accretion, using metabolites and hormones profiles, in Romane ewes reared under two contrasting farming systems (FS; (indoor, IND; extensive, OUT)). The ewes (n=173 IND; n=234 OUT) belonged to two genetic lines selected for low or high residual feed intake. They were monitored during their two first productive cycles at five key physiological stages (Mating, M; mid-Pregnancy, P; 2 weeks Pre-Lambing, bL; 3 weeks Post-Lambing, aL; Weaning, W). Parameters included body condition score (BCS) and metabolic profiles for plasma concentrations on non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHB), Triiodothyronine (T3) and insulin (INS). The relevant fixed effects and their interactions were investigated through analyses of variance using R. Physiological stage, parity, cohort, genetic line, and litter class were fixed effects while ewe and residuals were random effects. Depending on the parameter evaluated, the fixed effects and their interactions, with the exception of the genetic line, were statistically significant (P< 0.05). Regardless of the FS, results showed that BCS increased until P and declined thereafter. Highest NEFA concentrations were found from bL until W and at W in ewes reared IND or OUT, respectively. Significantly higher BHB levels than those found in M, P, and W were found in bL and aL ewes in both FS. T3 displayed a similar high trend throughout the stages with a peak at aL, and INS increased from P to aL before declining thereafter whatever the FS. These findings indicate that BR mobilization was displayed between P and W, as evidenced by BCS and blood parameters, whereas BR accretion occurred between W to P. Overall, there seems to be a consistent trend in Romane ewes’ capacity to mobilize and recover their BR irrespective of the FS. Plasma concentrations of metabolites and hormones at different physiological status can be an indicator of the ewe’s metabolic plasticity