HAL Université de Tours
Not a member yet
55851 research outputs found
Sort by
Costeley online : enfin une édition moderne pour l’œuvre complète de Guillaume Costeley
No full textInternational audienceCosteley online : enfin une édi0on moderne pour l'oeuvre complète de Guillaume Costeley</div
Is there a link between self-reported unmet needs and healthcare expenditure?
No full textInternational audienc
Décrypter les émotions équines par les expressions faciales
No full textInternational audienceFacial expressions linked to emotions, like observing behaviour and physiological responses, can provide valuable insights into the emotional state of horses. Through two examples involving sport horses, we have shown that these expressions can be used to assess how a horse perceives entering an obstacle course and to automatically categorise, using AI, AI, its state of comfort when being ridden. These results highlight the importance of integrating the study of facial expressions into research projects and applications aimed at improving equine welfare.Les expressions faciales liées aux émotions, tout comme l’observation du comportement et les réponses physiologiques, peuvent fournir des indications précieuses sur l’état émotionnel des chevaux. À travers deux exemples portant sur le cheval de sport, nous avons montré que ces expressions peuvent permettre d’évaluer la manière dont un cheval appréhende l’entrée sur un parcours d’obstacles et de catégoriser automatiquement, grâce à une IA, son état de confort lorsqu’il est monté. Ces résultats soulignent l’importance d’intégrer l’étude des expressions faciales dans les projets de recherche et dans les applications visant à améliorer le bien-être équin
The dynamic saddle-node bifurcation with noise on the slow variable
No full textIn this work, we analyse the effect of adding Gaussian white noise to the slow variable of a slow-fast system passing through a saddle-node (or fold) bifurcation. This problem is mainly motivated by applications to non-equilibrium energy sinks. While the effect of adding noise to the fast variable, which is important for noise-induced tipping, has been previously analysed in detail, the case where the slow variable is perturbed by noise has not been considered before. Our main result is that the noise increases the slow variable on average. We compute the effect of the noise, to lowest order, on the expectation and variance of the slow variable after the bifurcation. The contribution of the noise can be explicitly expressed in terms of Airy functions. We also provide numerical simulations, which show that the expansion to lowest order matches the observations for fairly large values of the noise intensity.</div
Assessing the relative influence of island climatic and geographical factors on body size in an endangered iguana species of the French Caribbean
No full textInternational audienceBody size is an important organismal trait on which many physiological and behavioral factors depend, and can be used to study how animals adapt to insular environments. In this regard, reptiles on islands exhibit remarkable size extremes, ranging from giants to some of the smallest vertebrate species in the world. In addition, the dependence of ectotherms on external temperature makes them particularly sensitive to climatic conditions. We tested the hypotheses that adult body size in Lesser Antillean iguanas ( Iguana delicatissima ) would increase with island area and isolation, as well as with increasing annual rainfall and ambient temperature. We used a database of 6878 individuals collected on seven islands in the French West Indies from 2009 to 2021. We measured individual size by the snout‐vent length. GLMM analyses showed that iguana body size increased with island size, and that iguanas on the islands located closer to the mainland were larger compared to those on islands located the furthest from the mainland. Regarding climatic conditions, we found that annual rainfall and ambient temperature had no significant effect on iguana body size. These findings indicate that geographical conditions have a greater influence on iguana size compared to climatic conditions. The lack of influence of climatic conditions may be related to the fact that iguanas are critically endangered, meaning that their populations consist of limited numbers of individuals far from the carrying capacity of their habitat. If ecological resources are not currently a limiting factor for Lesser Antillean iguanas, then conservation efforts could successfully promote the growth of their populations
Entry, replication and innate immunity evasion of BANAL-236, a SARS-CoV-2-related bat virus, in Rhinolophus and human cells
No full textAsian Rhinolophus bats are considered the natural reservoirs of an ancestral SARS-CoV-2. However, the biology of SARS-CoV-2-related viruses in bat cells is not well understood. Here, we investigated the replication of BANAL-236, the only bat-derived SARS-CoV-2 relative isolated to date, in Rhinolophus cells. BANAL-236 did not replicate in wild-type Rhinolophus cell lines. Entry assays using pseudoviruses expressing the spike proteins (S) of SARS-CoV-2, BANAL-236, and BANAL-52 revealed that efficient S-mediated entry depends on the expression of human ACE2 (hACE2) and human TMPRSS2 (hTMPRSS2) in human and Rhinolophus cells. Expression of Rhinolophus entry factors, either alone or in combination, did not facilitate SARS-CoV-2 or BANAL-236 entry in human cells, suggesting that the S protein of BANAL-236 interacts more efficiently with hACE2 than with its Rhinolophus counterpart (rACE2). Through biochemical, virological, and electron microscopy analyses, we showed that BANAL-236 and SARS-CoV-2 completed their replication cycles in a Rhinolophus cell line engineered to express high levels of hACE2 and hTMPRSS2. Despite efficient viral replication in modified Rhinolophus and human cells, no induction of interferon (IFN)-stimulated genes was detected. Using a screening approach, we identified several BANAL-236 proteins that antagonize IFN production and signaling in human cells. Our findings thus show that BANAL-236 possesses critical features that enabled zoonotic spillover: hACE2 usage and potent evasion of human IFN responses. The Rhinolophus cellular model we established offers a platform for further investigating the interactions between bat coronaviruses and their reservoir hosts. Author summary Bats are known reservoirs for viruses that cause severe diseases in humans, such as coronaviruses and filoviruses. Bat species naturally or experimentally infected with these viruses rarely exhibit clinical symptoms, suggesting an evolved tolerance to viral infections. To elucidate the mechanisms underlying viral tolerance and to identify factors that could facilitate zoonotic spillover, it is essential to study the replication of bat-borne viruses in relevant bat cellular models. Here, we investigated the replication of BANAL-236, a SARS-CoV-2 related virus isolated from fecal samples of Rhinolophus bats in Northen Laos, in a novel cell line derived from Rhinolophus ferrumequinum lung fibroblasts. Our findings reveal that BANAL-236 can efficiently use human entry factors and potently evade the human innate immune response, two traits that may have contributed to its zoonotic transmission. Furthermore, the R. ferrumequinum cell lines we developed is a valuable model for investigating the molecular interactions between sarbecoviruses and their natural hosts
D'ESLO à ESLO-FLEU : enjeux méthodologiques de la structuration de données pour la linguistique et la didactique du FLE
No full textInternational audienceThe ESLO-FLEU corpus is a subset of the Enquêtes Sociolinguistiques à Orléans (ESLO), a corpus of spoken French collected in two stages (ESLO1 1968-1970 and ESLO2 2008-), according to a similar methodology. Developed by sociolinguists and designed as an audio portrait of Orléans by its inhabitants, ESLO contains 422 hours of transcribed audio recordings collected in various communication situations and from a socially diverse panel of speakers. These data, which document French as it is spoken and its evolution over a period of 40 years, are of particular interest not only in linguistics, but also in the teaching of French as a foreign language. The dataset presented here, ESLO-FLEU (ESLO – Fle et Linguistique pour l'Enseignement Universitaire), is a selection of 150 excerpts lasting 2 to 4 minutes, chosen to highlight the heritage dimension of the corpus and to shed light on topics of conversation that are relevant to oral comprehension activities in French classes (everyday conversation, daily activities, social issues, testimonials about neighborhoods, leisure activities, professions, etc.). Indexed by theme and enriched with linguistic annotations, these excerpts are grouped into themes, sub-themes, and modules for an introduction to linguistics, and can be consulted online or downloaded from Ortolang in various formats depending on the needs of users, whether they are teachers or researchers in linguistics and didactics.Le corpus ESLO-FLEU est un sous-ensemble des Enquêtes Sociolinguistiques à Orléans (ESLO), corpus de français parlé collecté en deux étapes (ESLO1 1968-1970 et ESLO2 2008-), selon une méthodologie similaire. Élaboré par des sociolinguistiques et conçu comme le portrait sonore d'Orléans par ses habitants, ESLO contient 422h d'enregistrements sonores transcrits collectés dans différentes situations de communication et auprès d'un panel de locuteurs socialement diversifié. Ces données, qui permettent de documenter le français tel qu'il se parle et son évolution en l'espace de 40 ans, revêtent un intérêt particulier non seulement en linguistique, mais aussi en didactique du français langue étrangère. Le jeu de données présenté ici, ESLO-FLEU (ESLO -Fle et Linguistique pour l'Enseignement Universitaire) est une sélection de 150 extraits de 2 à 4 minutes, choisis pour valoriser la dimension patrimoniale du corpus et mettre en lumière des sujets de conversation correspondant à des thématiques pertinentes pour des activités de compréhension orale en cours de FLE (conversation ordinaire, activités quotidiennes, sujets de société, témoignages sur les quartiers, les loisirs, les métiers, etc.). Indexés par thèmes et enrichis d'annotations linguistiques, ces extraits, regroupés en thèmes, sous-thèmes et modules pour l'initiation à la linguistique, peuvent être consultés en ligne ou téléchargés sur Ortolang dans différents formats selon les besoins des utilisateurs, qu'ils soient enseignants ou chercheurs en linguistique et didactique