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Autonomic cardiac regulation to slow-paced respiration in seated and supine positions
No full textInternational audiencePurpose: Respiratory modulation and positional control are the main two regulators of cardiac autonomic activity. Although both slow-paced breathing and supine position promote parasympathetic regulation, their interaction remains poorly documented. Here, the objective of this work is to study the interaction between these two autonomic controls. Methods: Twenty healthy volunteers (12 males, 8 females), age of 25.9 ± 3.9 years were included in this study. They were randomly subjected to 6 different slow and controlled breathing at 4.5, 5, 5.5, 6, 6.5, and 7 min/cycles for 3 min in supine or seated position after a 3 min baseline recording in spontaneous breathing. ECG was continuously monitored and RR intervals (RRI), total power (Ptot), the standard deviation of normal R-R intervals (SDNN), high frequency power (HF), the root mean square of successive R-R interval differences (RMSSD), and low frequency power (LF) were calculated to study autonomic regulation. Results: We observed (1) a similar increase in parasympathetic (RMSSD and LF) and overall autonomic (RRI, Ptot, and SDNN) activities in slow-paced breathing conditions, whatever the respiratory rate in comparison with control spontaneous breathing; (2) these autonomic parameters increased in sitting position, but in parasympathetic (RMSSD and LF) and overall autonomic (Ptot, and SDNN) activities interacted with respiratory control and were higher in seated slow-paced breathing. Conclusion: These results showed that (1) whatever the slow-paced breathing frequency, slow breathing favours parasympathetic control and slow heart rhythm; and (2) seated position favors autonomic cardiovascular interaction between respiratory modulation and positional control
Improving penalty shoot-out performance in skilled youth soccer players: An imagery modality-based approach
No full textInternational audienceBackground: Since their introduction in professional football, penalty shoot-outs represent key moments in matches. Motor imagery (MI) can improve soccer performance, but different MI modalities can be used to mentally simulate motor actions. This study aimed to evaluate whether the MI modality used by the players would influence their penalty shoot-out performance. Methods: Twenty youth skilled football players from the Elite Center of the French Regions of America (CERFA) voluntarily participated in this experiment (M age = 16.4 years). After an assessment of their MI ability, the participants completed 4 counterbalanced experimental sessions spread over 4 weeks, each including the completion of 5 penalty shoot-outs. The sessions consisted of a control condition (count-down and actual execution) and 3 MI conditions during which the players had to mentally imagine themselves performing a penalty shoot-out according to one of the MI modalities: Internal Visual Imagery (IVI), External Visual Imagery (EVI), or Kinesthetic Imagery (KI), before kicking. Number of goals scored, shooting accuracy and ball speed were measured and served as dependent variables. Results: The soccer players benefited from MI. Indeed, in both the IVI and KI conditions, their performances were significantly higher than in the no-MI (i.e., control) condition with respect to the total number of goals scored and shooting accuracy variables
Synchronous Miocene radiations and geographic-dependent diversification of pantropical Xylopia (Annonaceae).
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Travaux de médiation scientifique - Réalisation d’un diaporama « Mode opératoire de coproscopie de strongles, parasites gastro-intestinaux des petits ruminants »
No full textLicenceLe stage a été conduit en médiation scientifique à l’UR ASSET INRAE. Des travaux menés par l’unité sur le parasitisme gastro-intestinal des petits ruminants sur le strongle Haemonchus contortus. Cela demande des analyses dont la (comptage des œufs dans les fèces) et la coproculture (identification des larves) pour pouvoir comprendre son mécanisme La mission consiste à réaliser deux diaporamas pédagogiques (niveau Bac et Licence) expliquant 2 techniques de laboratoire, en intégrant des photos, schémas et protocoles. Ces supports, destinés à être diffusés en accès libre, visent à rendre accessibles les savoir-faire techniques aux étudiants, stagiaires et visiteurs. De plus, j’ai pu être intégrée à une visite d’une classe de Terminale de Jardin d’Essai au centre INRAE Antilles-Guyane, me permettant d’aller à l’encontre d’un public cible des supports pédagogiques.Des activités secondaires ont été réalisées tels que l’accueil d’élèves de terminale (préparation et communication), la participation aux activités du laboratoire de l’UR ASSET (coproscopie et analyse de sang), la vérification des échantillons du Centre de Ressource Biologique... Le stage a permis une immersion dans un institut de recherche publique, incluant des visites des unités ASSET, PTEA (élevage expérimental) et ASTRO (collections), une visite du CRB de l’unité ASSET Il a contribué à développer des compétences en communication scientifique, en techniques de laboratoire et en compréhension des enjeux de l’agroécologie en milieu tropical. La notion de médiation scientifique est essentielle puisqu’elle permet de transformer des connaissances scientifiques en une culture partagée, nécessaire pour faire face collectivement aux grands défis de l’innovation agroécologiqu
Multi-scale Study of the Effect of a Living Yeast-Based Biostimulant on Soybean
No full textInternational audienceUsing biostimulants to improve crop productivity represents a promising agroecological practice to reduce dependency on chemical inputs. In the context of achieving self-sufficiency in plant protein for alimentation, the rise of protein crops constitutes a major issue in Europe. Soybean draws particular attention because of its multiple agronomic benefits and outputs. However, its deployment is often constrained by pedoclimatic conditions. Here, a preliminary greenhouse experiment was carried out to evaluate the potential benefit of a seed-surfacing treatment with a living yeast-based biostimulant (YB) on soybean growth using an holistic approach exploring the underlying mechanisms in plant and soil compartments. A global promotion of plant growth was observed, mainly focused on the root compartment. Proteomic analysis performed on leaves and roots revealed increased abundance of proteins involved in key pathways, such as the biosynthesis of secondary metabolites and energy metabolism. In parallel, YB application was associated with changes in the composition of the microbial community at the early (V2) and mature (V5) stages. At V5 stage, YB tended to enhance microbial enzymatic activities linked to C cycle and significantly induced those related to P cycle. These results suggested a potential role of the living YB in promoting soybean growth and modulating plant-microbiome interactions. Further validation under field conditions and across diverse genotypes is now necessary to confirm their broader relevance. This work also emphasised the importance of considering the entire holobiont-plant with associated microbiome-to better understand the action of biostimulants
Splenic accumulation of intact Plasmodium ovale sensu lato-infected red blood cells in a patient presenting with splenic rupture
No full textInternational audienceA 35-year-old man had splenic rupture just after starting antimalarial treatment with atovaquone-proguanil followed by artesunate for acute Plasmodium ovale sensu lato infection. Spleen histology showed a 10-fold accumulation of intact P. ovale s.l. -infected erythrocytes in the spleen parenchyma compared to the general circulation. Infected erythrocytes also accumulated in small extra-splenic blood vessels, suggesting cytoadherence
Weak adversarial networks for solving 2D incompressible Navier-Stokes-Brinkman equations
No full textThe use of neural networks has shown significant potential to reduce the computational costs associated with the dynamics of industrial computational fluids. Weak adversarial networks (WAN) leverage weak solution theory to transform the problem of solving PDEs into a Min-Max optimization problem, which is then solved by training a generative adversarial network. Although this method has been successfully applied to two-dimensional (2D) Navier-Stokes (NS) equations, previous work says nothing about the Navier-Stokes-Brinkman (NSB) equations. In this study, we first leverage the stream function to introduce the biharmonic 1 formulation of NSB equations. Then, we extend the WAN framework to solve NS equations in porous media (WAN2DNSB) and provide free surface flow as a numerical experiment. Our results demonstrate the stability and accuracy of the proposed method, highlighting its advantages over the traditional Physic-Informed Neural Networks (PINNs) algorithm, particularly for problems lacking strong solutions. This work contributes to the growing research on AI-driven numerical methods for complex fluid dynamics problems, offering a promising approach for industrial applications
Introduction. Les sports d'hiver au révélateur de l'Olympisme
No full textInternational audienceCe chapitre introductif propose de tracer minutieusement l’évolution historique des Jeux olympiques d’hiver. Il explore le contexte et les conditions de leur avènement, les dynamiques institutionnelles qui s’y jouent, les mutations de leurs programmes successifs, les méandres géopolitiques dans lesquels ils se meuvent et les résistances auxquels ils font face. En somme, si les Jeux olympiques d’hiver sont un évènement majeur du calendrier sportif international, ils sont tout sauf un « allant de soi » comparé à leurs homologues estivaux
Reciprocal relationships between sleep quality, mental health and the quality of life in elite athletes: A pilot study
No full textInternational audienceWe aim to investigate the relationship between sleep quality, psychological health, and qualityof life (QOL) in highly trained athletes. Elite athletes (n = 118, 20.1 ± 0.64 years; 39 females; 50 world class;102 aged ≤ 25 years; and 76 practicing individual sports) responded to the Pittsburgh sleep quality index (PSQI),insomnia severity index (ISI), Epworth sleepiness scale (ESS), Depression, anxiety and stress scale (DASS), worldhealth organization QOL (WHOQOL), and bespoke questions related to sleep hygiene. High percentages of thesample reported low or very low sleep quality (62%), moderate or excessive daytime sleepiness (51%), sleeping7 hours or less (60%), and moderate or severe insomnia (16%), implying a modest sleep health. Female athletesreported higher PSQI (p < 0.05; d = 0.25), ESS (p < 0.05; d = 0.37) and DASS (p < 0.05; d = 0.27) scorescompared to males. Young athletes (i.e., ≤ 25 years) reported higher PSQI (p < 0.05; d = 0.49) and DASS(p < 0.05; d = 0.34) scores compared to older athletes (i.e., > 25 years). Individual-sport athletes reportedhigher ESS (p < 0.05; d = 0.37) and lower QOL (p < 0.01; d = 0.51) scores compared to team-sport athletes.Higher DASS scores were associated with higher PSQI (t = 3.68; β = 0.3) and ISI (t = 4.78; β = 0.36) scores.Lower physical health (i.e., sub-scale of WHOQOL) was associated with higher DASS (t = -5.01; β = -0.42)and ISI (t = -8.02; β = -0.61) scores. Higher PSQI scores contributed to lower WHOQOL scores (t = -4.81;β = -0.41). In summary, the current study highlights reciprocal relationships between low sleep quality, lowmental health and low QOL. Elite athletes (especially sub-groups of female, individual, and young athletes)showed a low sleep quality, potentially affecting their physical and psychological health and QO
Rapport sur les services climatiques réussis dans le monde et leurs critères de succès: Livrable commun au Projet ciblé TRACCS-PC1-DIALOG (D5.3) et au Projet Ciblé TRACCS-PC3-DEMOCLIMA (D1)
No full textLes enjeux socio-économiques liés aux effets du réchauffement climatique sont tels qu’une demande croissante d’informations climatiques adaptées pour la mise en place de stratégies d’atténuation et/ou d’adaptation est clairement exprimée par les secteurs économiques (e.g. agriculture, énergie, tourisme, infrastructures terrestres ou maritimes, etc…) et par les territoires/régions qui mesurent pleinement leursvulnérabilités. En réponse à ces demandes, de nombreux projets de recherche nationaux (e.g., la "Convention relative à l’attribution d’un appui financier au bénéfice des services climatiques", signée entre le Ministère de la Transition Écologique et Solidaire (MTES) et le CNRS en mars 2017, ou le développement du portail DRIAS), européens (e.g., le programme ERA4CS « European Research Area for Climate Services » du JPI Climate, ou encore Copernicus) ou internationaux (e.g., les outils développés par la NASA, le GIEC…) ont permis le financement de « services climatiques ». Plusieurs acteurs opérationnels nationaux et européens développent et mettent à disposition des « services climatiques » via des plateformes souvent libres d’accès et enfin, apparaissent sur le marché des bureaux d’études dont l’activité commerciale vise le développement de « services climatiques » à la carte et adaptés aux demandes des clients.L’offre pour les « services climatiques » est donc aujourd’hui multiforme par l’information fournie (données climatiques « simples », indicateurs, outils d’aide à la décision) et par son mode de développement. Face à cette diversité, les enjeux sont de documenter et comprendre le paysage des services climatiques actuels, de faire ressortir les besoins, et de se munir de moyens pour caractériser la réussite des services climatiques, pour évaluer l'existant et guider le développement de nouveaux projets. Menée conjointement par les projets ciblés DIALOG (PC1) et DEMOCLIMA (PC3) du PEPR TRACCS, cette étude vise quatre objectifs :i) Documenter le paysage actuel des services climatiques (section 2) en France et dans le monde (identifiés par la communauté TRACCS) en les présentant par usages et cibles ;ii) Identifier des besoins non satisfaits vis-à-vis des services climatiques (section 4) ;iii) Identifier un ensemble de critères de réussite d'un service climatique pour les évaluer (section 5) ;iv) Proposer des bonnes pratiques pour atteindre ces critères de réussite (section 6); ces éléments guideront les choix des futurs démonstrateurs qui seront conçus et développés au sein de DEMOCLIMA.Notre travail repose en grande partie sur le recueil de dires d'acteurs des "services climatiques", dans une approche "bottom-up"