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Characterization of POP mixture redistribution and identification of their molecular signature in xenografted fat mice
No full textInternational audiencePersistent organic pollutants (POPs) are associated with many adverse health effects in humans, including cancers, immune, reproductive, neurological disorders and metabolic diseases. These chemicals are known to accumulate in fatty tissues, from which they can be released in other tissue compartments of living organisms, in particular, upon weight loss. This dynamic distribution of POPs remains, however poorly investigated. In this study, a xenografted POP-contaminated adipose tissue (AT) model was used to assess 1) their concentrations in the ATs, the liver and the brain and 2) their associated effects by transcriptomics, metabolomics and lipidomics approaches. In the ATs, the liver and the brain of mice grafted with POP-contaminated fat pad, most of POPs were detected 3 days and 21 days after the graft with the highest concentrations in the ATs and the lowest concentrations in the brain. Conversely, per- and polyfluoroalkyl substances presented a distinct profile as they persist in the liver but not in the ATs or in the brain. In the AT of POP-exposed mice, the most dysregulated pathways were related to mitochondrial functions, endobiotic (carbohydrate, lipid, amino acid) and xenobiotic metabolism and inflammatory response. In the liver of grafted mice, many pathways related to mitochondrial functions and metabolism were dysregulated. These results support that realistic mixture of POPs that accumulate in AT and liver induces a systemic metabolic dysfunction which may represent the mechanisms by which the POPs can promote metabolic diseases such as obesity, type 2 diabetes and cardiovascular diseases
L'intelligence artificielle, un levier pour accompagner les transitions en élevage ?
No full textNational audienceL'intelligence artificielle, un levier pour accompagner les transitions en élevage ? Depuis plus de 20 ans, des services numériques conçus par la recherche et les entreprises privées ont aidé les agriculteurs dans leurs pratiques d’élevage. Avec l’intelligence artificielle, un pas de plus est franchi. Entre bénéfices, limites et impacts, quelles sont aujourd’hui les applications qui se profilent en élevage
Development of nebulized inhalation delivery for fusion-inhibitory lipopeptides to protect non-human primates against Nipah-Bangladesh infection
No full textInternational audienceNipah virus (NiV) is a lethal zoonotic paramyxovirus that can be transmitted from person to person through the respiratory route. There are currently no licensed vaccines or therapeutics. A lipopeptide-based fusion inhibitor was developed and previously evaluated for efficacy against the NiV-Malaysia strain. Intraperitoneal administration in hamsters showed superb prophylactic activity and promising efficacy, however the intratracheal delivery mode in non-human primates proved intractable and spurred the development of an aerosolized delivery route that could be clinically applicable. We developed an aerosol delivery system in an artificial respiratory 3D model and optimized the combinations of flow rate and particle size for lung deposition. We characterized the nebulizer device and assessed the safety of lipopeptide nebulization in an African green monkey model that mimics human NiV infection. Three nebulized doses of fusion-inhibitory lipopeptide were administered every 24 h, resulting in peptide deposition across multiple regions of both lungs without causing toxicity or adverse hematological and biochemical effects. In peptide-treated monkeys challenged with a lethal dose of NiV-Bangladesh, animals retained robust levels of T and B-lymphocytes in the blood, infection-induced lethality was significantly delayed, and 2 out of 5 monkeys were protected from NiV infection. The present study establishes the safety and feasibility of the nebulizer delivery method for AGM studies. Future studies will compare delivery methods using next-generation fusion-inhibitory anti-NiV lipopeptides to evaluate the potential role of this aerosol delivery approach in achieving a rapid antiviral response
Experimental and numerical study of wall phenomena of confined bubble flow in a square channel
No full textInternational audienceConfined bubbly flow, including bubbles of 4.2 and 6.7 mm equivalent diameters rising in a 4 mm square channel, was experimentally and numerically investigated for liquid Reynolds numbers of 0 and 28. Wall shear stress measurements, by means of polarographic method, were used to investigate wall phenomena while the film thickness was estimated using a conductimetric technique. The OpenFOAM package was used for the numerical simulation. The presence of reverse flow in the liquid layer between the bubble and the wall depends on the length of the bubble as well as its velocity. The liquid layer thickness decreases with increasing bubble size. It was shown that the minimal liquid layer thickness between the bubbles and the wall is 10 µm for an elongated bubble and 36 µm for a spherical bubble, which is confirmed by numerical simulation. A liquid acceleration zone exists in the center of the channel in the wake of the bubble, and the existence of vortices near the channel walls at some distance from the bubble is also shown
A Bayesian optimization approach for data-driven Petlyuk distillation column
No full textInternational audienceRecently, the focus on increasing process efficiency to reduce energy consumption has driven the adoption of alternative systems, such as Petlyuk distillation columns. It has been proven that, when compared to conventional distillation columns, these systems offer significant energy and cost savings. From an economic standpoint, achieving high-purity products alone does not ensure the feasibility of a process. Instead, balancing the trade-off between product purity and cost necessitates multi-objective optimization. While conventional optimization methods are effective, novel strategies like Bayesian optimization offer distinct advantages for handling complex systems. Bayesian optimization requires no explicit mathematical model and can efficiently optimize even when starting from a single initial point. However, as a black-box method, it demands a detailed analysis of hyperparameters, such as the acquisition function and the number of initial points, to ensure optimal performance. This work presents a case study of a Petlyuk distillation column, focusing on the influence of key hyperparameters in Bayesian optimization. Additionally, the role of uncertainty in the optimization process is explored, as it is a critical factor in real-world applications. By simulating uncertainty, this study provides insights into its impact on the optimization process.</div
Pourquoi les directives en matière de santé ne sont-elles pas respectées ? Le rôle de la distance envers la maladie et de la réactance envers ces directives
No full textInternational audienceLes incidences du non-respect de directives sanitaires (par exemple, lors d’une pandémie,la distanciation sociale et les gestes d’hygiène) peuvent être désastreuses pour la santé publique. Comment pouvons-nous expliquer de tels comportements ? Cet article cherche à comprendre le non-respect des comportements préconisés d’hygiène, de distanciation sociale et de respect du confinement par la distance envers la maladie. La réactance envers les directives sanitaires est considérée comme un modérateur de cette relation
Relationship Between Ball Speed and Spin in Elite Youth Table Tennis Players Using Optical Sensors
No full textInternational audienceThis paper investigates the relationship between ball spin and linear speed in table tennis. This study uses a simple photodiode montage to introduce a methodology for measuring spin based on light reflection on the ball’s surface. Two optical-based measurement systems were developed to measure either the ball’s speed or spin. This paper describes sensor calibration and error estimation. Those systems measured ball kinetic parameters from nine young elite players (aged 15 ± 1.5 years) who volunteered to perform 4 exercises. Results showed a strong positive linear relationship between the ball’s speed and spin (r = 0.96, R2 = 0.93, p < 0.001). The effect of exercise conditions on ball speed has been studied using a statistical test, ANOVA. Results showed a significant main effect of exercise conditions on ball speed (p < 0.05) with a very large effect size (η2 = 0.82). The study revealed significant variations in linear speed based on the type of stroke (backhand, forehand) and the incoming ball’s spin (topspin, backspin), with topspin forehand strokes achieving higher speeds compared to backhand strokes. These findings provide valuable knowledge for players to enhance performance in a competitive environment
Comment désinfecter mon écurie en pratique ?
No full textNational audienceDe nombreuses maladies infectieuses et contagieuses peuvent toucher les chevaux. Il est important de savoir les détecter et les diagnostiquer, mais il est fondamental également de gérer l'environnement de ces chevaux pour que celui-ci ne devienne pas une source de re-contamination car les virus / bactéries peuvent survivre pendant parfois de longues périodes sur les murs des boxes, le sol, ...Une des clés de la gestion de l'environnement est le nettoyage et la désinfection des locaux : comment faire en pratique ? Avec quel matériel ? Quels types de produits ?Ces différents points sont abordés au cours de cette webconférence
Greenhouse gas reduction in the agrifood industry: Challenges, levers and prospects
No full textThis issue follows on from the Carrefour de l'innovation agronomique, forum dedicated to reducing the carbon footprint of agricultural and agri-food activities, which took place on September 19, 2024: - analyzing the trajectory of carbon footprint reduction in various activities related to agriculture and food (crops, livestock, agricultural inputs, food production) based on certain innovations- how stakeholders in agriculture and agri-food are committed to innovation aimed at carbon neutrality.International audienceIn France, the food processing industry consumes a significant amount of energy for the transformation processes dedicated to food products. These industries are also characterized by the indirect environmental impact of their activities, due to food transport and product packaging. To assess these environmental impacts, the carbon footprint methodology is a powerful tool for quantifying the direct and indirect greenhouse gas (GHG) emissions associated with the activity of the organization. In this context, reducing GHG emissions in the agri-food sector is a strategic objective. Several technological levers, such as the reduction of material losses or the energy recovery within industrial processes, can have a positive impact for the carbon footprint of industry. These technological levers need to be considered in conjunction with the methodological tools used to manage production flows in a factory, and must also be seen in the light of evolving regulations imposed by public authorities (anti-waste law for a circular economy for example). Through targeted action and the involvement of all stakeholders, it is possible to limit these impacts and promote more environmentally friendly food production. The low-carbon transition thus requires a systemic approach, combining technological, organizational and strategic innovations
Évaluation de la mise en place d'un ECOS (Examen Clinique Objectif et Structuré) comme modalité d'examen des étudiants de 5ème année au cours de la rotation de médecine individuelle bovine (UE 099) à Oniris VetAgroBio Nantes
No full textL’Examen Clinique Objectif et Structuré, ou ECOS, est un format d’examen créé en 1975 pour évaluer les compétences cliniques des étudiants en santé de manière fiable, équitable et valide. Cette modalité d’examen est utilisée en médecine humaine en France depuis quelques années. En médecine vétérinaire, les ECOS sont mis en place seulement à l’étranger. Un ECOS est un examen chronométré, identique et répétable au cours duquel les étudiants évoluent sur un circuit composé de plusieurs stations. Chaque station ECOS aborde une situation clinique où l’étudiant doit réaliser un nombre limité de tâches. Une station fait intervenir un patient standardisé et un examinateur. La standardisation de chaque station est essentielle afin de produire un examen objectif et structuré. Elle passe par la formation des patients standardisés et l’utilisation de grilles d’évaluation. L’objectif de ce travail est d’évaluer la mise en place de cette modalité d’examen au cours de la rotation de médecine individuelle bovine à Oniris VetAgroBio Nantes pour faire suite à un premier travail déjà réalisé de création d’un ECOS durant cette rotation. Au cours de ce précédent travail, la phase de test pilote des stations n’avait pas pu être réalisée. Après avoir étudié la bibliographie sur la mise en place d’un ECOS, 6 stations parmi les 47 créées au cours du précédant travail ont été testées. Deux tests pilotes ECOS formatifs successifs et composés de ces 6 stations ont été mis en place à la fin des 2 semaines d’optionnel de médecine individuelle bovine. Ces deux tests pilotes ont été menés sur un total de 21 étudiants de 5ème année de médecine vétérinaire à Oniris VetAgroBio Nantes, lors du premier semestre AP-EQ-SPV (Animaux de Production – Équine – Santé Publique Vétérinaire). Il est faisable de mettre en place un ECOS formatif pour une dizaine d’étudiants. Les différents intervenants sont favorables au développement de cet examen. Les 6 stations testées nécessitent cependant d’être révisées. Les grilles d’évaluation doivent être retravaillées pour être plus fiables. Après cela, ces stations pourront intégrer une banque de stations ECOS finale utilisable lors de la rotation de médecine individuelle bovine