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Preferential localization of Escherichia coli in dairy emulsions: Influence of milk lipid droplets surface composition on bacterial adhesion
No full textInternational audienceIn food emulsions such as raw milk, the lipid droplets exhibit an interfacial layer possibly the site of interactions with bacteria, including the shiga toxin-producing Escherichia coli (STEC). Some pathogenic E. coli strains can adhere to intestinal cells after ingestion or to ligands that could modulate their pathogenicity such as those present at the surface of emulsion lipid droplets. The objectives of this study were to investigate the preferential localization of E. coli cells, AEEC 4315-A strain belonging to the O26:H11 serotype, as a function of the surface composition of emulsion lipid droplets i.e. milk fat globule membrane (MFGM) surrounding raw milk fat globules, milk polar lipids or whole milk proteins. The emulsions were artificially spiked with E. coli from an overnight culture in Brain Heart Infusion broth. Then, the E. coli cells were enumerated in the lipid droplet enriched creams and in the skimmed phases recovered after centrifugation. The localization of the E. coli cells in the creams was observed by confocal laser scanning microscopy (CLSM). This study revealed the role played by the surface properties of dairy lipid droplets on the adhesion of E. coli. For milk fat globules, the concentrations of E. coli in the creams were about 10 times higher than in the aqueous phase. In the processed emulsions, E. coli cells were concentrated in the aqueous phase. The CLSM images showed the adhesion of E. coli to the MFGM containing glycoproteins and their mobility as a function of time in the aqueous phase surrounding lipid droplets. This study provided additional scientific information supporting a specific affinity of E. coli for the MFGM of raw milk fat globules
« Et Geiseric rasa les remparts de toutes les cités ». De l’inutilité des fortifications : un concept vandale de la défense ?
No full textInternational audienceCommunication presented as part of a round table for Master and Doctorat students under the direction of Isabelle Pimouguet-Pedarros. This 7th edition of the round table on war violence, which Pimouguet-Pedarros has been directing for years, focuses on the subject of violence in the context of siege warfare, as it is titled, “Guerre de siège et violences de masse de l'Antiquité à nos jours (Siege warfare and mass violence from Antiquity to the present days).From 462 to 476, Geiseric, king of the Vandals, took care to level the walls of the cities under his control, with the exception of those of Carthage. The rapid fall of the Vandal kingdom in 533 is sometimes attributed to this alleged strategic error. Yet, fortified cities in Vandal Africa were not that absent. The idea that this decision was the result of political incompetence is itself a retrospective interpretation of the decision. During the Justinian Wars, it is assumed that the destruction in Africa was less palpable than that of Italy, and even this "small amount" of destruction is difficult to support by archaeology. The concept of “protection” also seems to have been absent from the Vandals' vision of “defense”, as portrayed by Procopius of Caesarea. This communication proposes some hypotheses that attempt to explain the Vandal dismantling enterprise, apart from alleged “poliorcetic incompetence”, all by connecting it to the appearant Vandal aversion to fortified cities in 533.Communication dans le cadre d'une table ronde Master Doctorat sous la direction d'Isabelle Pimouguet-Pedarros. Cette 7ème édition de la table ronde axée sur les violences de guerre, que Madame Pimouguet-Pedarros dirige depuis des années, eut pour thématique la question des violences dans le cadre de la guerre de siège comme son titrage l'indique, "Guerre de siège et violences de masse de l’Antiquité à nos jours".Entre 462 et 476, Geiseric roi des Vandales aurait pris soin de raser les murailles des villes sous son contrôle à l’exception de ceux de Carthage. La chute rapide du royaume vandale en 533 est parfois attribuée à cette prétendue erreur stratégique. Néanmoins, l’idée selon laquelle cette décision découlerait d’une incompétence poliorcétique relève elle-même d’une interprétation rétrospective de cette décision. Sous les guerres de Justinien, il est estimé que le bilan des destructions en Afrique fut bien inférieur à celui de l’Italie ; ceci est difficilement soutenable par l'archéologie. À travers les choix militaires vandales, le concept de « protection » semble absent de leur vision de la « défense » que leur portrait Procope de Césarée. Cette communication propose des hypothèses qui tentent d'expliquer l'entreprise de démantèlement en dehors de la prétendue "incompétence poliorcétique" tout en mettant en relation l'aversion vandale des villes fortifiées en 533
Transfer learning assessment of small datasets relating manufacturing parameters with electrochemical energy cell component properties
No full textInternational audienceThe performance of electrochemical cells for energy storage and conversion can be improved by optimizing their manufacturing processes. This can be time-consuming and costly with the traditional trial-and-error approaches. Machine Learning (ML) models can help to overcome these obstacles. In academic research laboratories, manufacturing dataset sizes can be small, while ML models typically require large amounts of data. In this work, we propose a simple but still novel application of a Transfer Learning (TL) approach to address these manufacturing problems with a small amount of data. We have tested this approach with pre-existing experimental and stochastically generated datasets. These datasets consisted of component properties (e.g., electrode density) related to different manufacturing parameters (e.g., solid content, comma gap, coating speed). We have demonstrated the robustness of our TL approach for manufacturing problems by achieving excellent prediction performance for electrodes in lithium-ion batteries and gas diffusion layers in fuel cells
The ambition for a one-and-done vision-saving AAV vector
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Milieu scolaire inclusif : entre tensions paradoxales et praxis critique, quel leadership des chefs d’établissement ?
No full textInternational audienceL'ambition d'une école inclusive, réaffirmée par la loi française de 2019 "l'école de la confiance", place leschefs d'établissement face à des défis complexes. Confrontés à des injonctions paradoxales, ils doiventmobiliser les acteurs locaux (Buisson-Fenet & Dutercq, 2015) et promouvoir une culture de travail en équipe(Crouzier, 2008). Cependant, les modalités concrètes de leur action restent floues (Guirimand & Mazereau,2016). Cette communication explore les perceptions des chefs d'établissement sur le leadership inclusif etleur rôle dans la création d'une "Communauté Éducative Inclusive" (Pombet et al., 2024). En s'appuyant surune recherche qualitative et inductive, incluant des entretiens et une analyse de documents, les premiersrésultats montrent que les chefs d'établissement naviguent entre individualisation et standardisation,innovation et résistance au changement, bienveillance et exigence. Ces tensions soulignent l'importance d'unleadership agile et conscient des paradoxes (Ancelin-Bourguignon, 2018) pour transformer l'école vers unevéritable inclusio
Vers des politiques des cycles de l'eau
No full textInternational audienceEn 1964, la France se dotait de véritables institutions de bassin-versant. Alors que ces Agences de l’eau ont fêté leurs soixante ans en 2024, nous avons voulu proposer de mettre en discussion, de façon fractale et diverse, ce que pourraient être non pas seulement des « politiques de l’eau », mais des « politiques des cycles de l’eau » qui soient aptes à accompagner les vies troublées par les bouleversements écologiques et sociaux, en cours et à venir. Les cycles de l’eau, en effet, tout comme le climat, se dérèglent. Alors que déjà nous les comprenons mal dans toute leur complexité (de surface, souterrains, atmosphériques, bleus ou encore verts), les cycles de l’eau soutiennent pourtant l’ensemble de nos modes de vie – et même plus largement, toute forme de vie. À l’heure des bouleversements écologiques, ces cycles de l’eau apparaissent de moins en moins renouvelables et de moins en moins inépuisables. Dès lors, comment donc envisager des politiques, des pratiques et des représentations collectives qui se mettent à la hauteur de l’eau, de ses sagesses et des risques qu’elle porte ? Actes du colloque éponyme tenu à Cerisy en mai 2024, avec les contributions de Charles Ambrosino, Philippe Aubert, Alice Barbaza, Antoine Brochet, Marlène Buchy, Marine Calmet, Julien Chapuis, Antoine Devillet, Anna Desreaux, Roberto Epple, Emma Haziza, GANG, Jérôme Gaillardet, Théophile Gervais, Maële Giard, Sophie Gosselin, David gé Bartoli, Patrick Laigneau, Caroline Lejeune, Somhack Limphakdy, Prisca Lobjoy, Marie Lusson, Clémence Mathieu, Jean-Louis Michelot, Chloé Pelletier, Barbara Réthoré, Mathias Rollot, Frédéric Rossano, Elisabeth Taudière, Nicolas Tixier, Marin Schaffner, Fanny Vincent
Anna Maria van Schurmann Pourquoi il convient à une femme chrétienne de faire des études
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Investigating quarkonium collectivity in heavy-ion collisions
No full textInternational audienceThe quark-gluon plasma (QGP) produced in ultrarelativistic heavy-ion collisions has exhibited properties of a mostly perfect fluid. These properties can be observed through the hydrodynamic expansion of the QGP. Experimentally, this was established by measuring azimuthal anisotropies in the final state, known as elliptic flow () or higher order harmonics such as triangular flow (). These Fourier harmonic coefficients have been extensively measured in past experiments using inclusive charged particles or identified particles in the soft sector. Interestingly, measuring such coefficients using hard probes, such as quarkonia, brings additional information about heavy-quarks production and thermalization in the QGP. In this study, we investigate quarkonia collectivity using Run 3 data collected in 2023, presenting new flow measurements. We employ different experimental methods to extract flow coefficients, including the scalar product, event plane, and cumulant methods. These results will impose new constraints on theoretical models, enhancing our understanding of quarkonia behavior in heavy-ion collisions
Introduction : Des parcours sous influences territoriales
No full textNumber: 169 Publisher: La documentation françaiseInternational audienceLe thème de ce dossier, « Des parcours sous influences territoriales » interroge les rapports entre société et espace en mobilisant la géographie dans un contexte interdisciplinaire. Ce questionnement, amorcé lors des 28es journées du longitudinal à Caen, appelle des analyses croisées, où la géographie interagit avec la sociologie, l’économie, la démographie, les sciences de gestion, les sciences de l’éducation et les sciences politiques. En effet, « le mot-clé de territoire est devenu incont..
Feeling of exposure to fluviomarine risks and adaptation strategies in the Loire estuary
No full textInternational audienceEstuaries are low- elevation morphological areas that are highly susceptible to submersion and flooding, and particularly so in view of the rising sea level. As with coastlines, where many adaptation strategies are under consideration (relocation, adaptation of buildings, nature-based solutions, etc.), future adaptation strategies for estuaries involve a number of different ways of converting the area, all of which must be developed on the appropriate spatial and temporal scales and in agreement with the local people. In this regard it is appropriate to examine the views of local residents in an estuarine context. Do they feel vulnerable? What are their perceptions of how planning has evolved in relation to climate change, and what are their preferences in respect of risk management? This article presents the results of an enquiry carried out downstream of the Loire estuary in an area characterized by industry, urban development and natural spaces. The survey involved 633 individuals whose views on the relationships between the local residents and their territory, in terms of fluviomarine risks and adaptation procedures, were collected by completing a questionnaire. The results reveal that few of the people surveyed are worried about fluviomarine risks, although they are aware of the ongoing climate change and that areas close to where they live are under threat. On the other hand, they feel much more threatened by the industrial risk which is characteristic of the Loire estuary. In terms of adaptation strategies the results are highly consensual, although sometimes confused, and could reveal a lack of ‘concern’ about these topics. The results of this research highlight determining factors such as time spent in the community and at home, the elements inherent to estuarine environments, and the memory of local risks. These elements could be useful for stakeholders in large industrialized estuaries wishing to embark on an adaptation strategy or submersion risk management