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Bron (69), Campus porte des alpes, 5 avenue Pierre Mendès France
No full text1 VOLUMEMalgré l’arasement important des vestiges, les fouilles menées sur le parking de L’Université Lumière-Lyon 2 à Bron ont permis de mettre au jour plusieurs structures datées du Néolithique, des aménagements liés à un petit établissement rural antique et une importante série de fosses historiques. Quatre foyers à pierres chauffées datés du Néolithique ancien ont été découverts. Ils seraient contemporains d’un dépôt secondaire à incinération. L’occupation antique présente deux tats d’occupation. Une première phase du Haut-Empire n’a laissé que peu de structures appartenant à de petites entités domestiques. Au Bas-Empire, un petit établissement rural se met en place, délimité au nord par un fossé curviligne. Il s’organise autour d’une dépression ayant probablement servi de mare et comprend une zone artisanale et domestique localisée au nord ainsi qu’un puits et un espace probablement lié à la stabulation ou au stockage à l’ouest. L’ensemble de l’emprise est par ailleurs marqué par la présence de petits aménagements rectangulaires médiévaux ou modernes, comblés exclusivement de galets et disposés selon un système orthonormé. Il pourrait s’agir de limites de parcelles en lanières ou de fosses de plantations d’arbustes ou de petits arbres
Generalized principal eigenvalues for parabolic operators in bounded domains
No full textWe introduce here new generalized principal eigenvalues for linear parabolic operators with heterogeneous coefficients in space and time. We consider a bounded spatial domain and an unbounded time interval I := R, R + or R -, and operators with coefficients having a fairly general dependence on space and time. The notions we introduce rely on the parabolic maximum principle and extend some earlier definitions introduced for elliptic operators [3, 5]. We first show that these eigenvalues hold the key to understanding the large time behavior and entire solutions of heterogeneous Fisher-KPP type equations. We then describe the relation of these quantities with principal Floquet bundles for parabolic operators which provides further characterizations of the principal eigenvalues. These allow us to derive monotonicity properties and comparisons between generalized principal eigenvalues, as well as perturbation results and further properties involving limit operators. We show that the sign of these eigenvalues encodes different versions of the maximum principle for parabolic operators. Lastly, we explicitly compute the generalized principal eigenvalues for several classes of operators such as spatial-independent, periodic, almost periodic, uniquely ergodic or random stationary ergodic coefficients
Pour une meilleure prise en compte de l’influence de l’image de la destination touristique sur les intentions comportementales des résidents
No full textInternational audienceL'objectif de cette recherche est d'analyser la mesure de l'Image de la Destination Touristique (IDT) dans un contexte français en se concentrant sur un public de visiteurs relativement peu étudié, à savoir les résidents de la destination. L'étude a porté sur 422 habitants de la ville de Nantes (France) et a analysé l'impact de l'IDT sur leurs intentions comportementales. Les résultats identifient des relations positives entre les images cognitives et affectives, et leurs influences respectives sur les intentions de recommandation et de revisite des résidents
Guix-HPC Activity Report 2023-2024
No full textGuix-HPC is a collaborative effort to bring reproducible software deployment to scientific workflows and high-performance computing (HPC). Guix-HPC builds upon the GNU Guix software deployment tools and aims to make them useful for HPC practitioners and scientists concerned with dependency graph control and customization and, uniquely, reproducible research.This report—our seventh report!—highlights key achievements of Guix-HPC between our previous report a year ago and today, February 2025. This year was marked by exciting developments for HPC and reproducible workflows. Significant advances were made in integrating Guix into the complex software landscape of HPC, taking the roles of software manager, workflow execution engine, backend for generating container images, or provider for the complete operating system layer. Support for reproducing computations from the past was also much improved. And, as usual, we have been using Guix for research, and teaching other researchers how to get started
Dynamic and spillover effects of armed conflicts on renewable energy in Subsaharan Africa
No full textInternational audienceThis paper investigates the impact of armed conflicts on renewable energy consumption in 46 Sub-Saharan African countries over the period 2000–2020. Understanding this relationship is crucial, as the transition to renewable energy is essential for sustainable development, yet it may be undermined by political instability and violent conflict. The study employs a dynamic spatial econometric approach to capture both spatial and temporal effects of armed conflicts on renewable energy use. Using the dynamic spatial Durbin model, the findings reveal that armed conflicts exert a significant negative influence on renewable energy consumption. The estimated impact is 18.76 % in the dynamic model, compared to 17.58 % in the non-dynamic model. Spatial spillover effects suggest that armed conflicts, through contagion and diffusion mechanisms, negatively affect renewable energy consumption in neighboring countries by approximately 14 %. Both short and long term effects are generally negative and statistically significant. Heterogeneity analysis indicates that terrorism has a more pronounced effect than other types of conflict. Additionally, the impact of armed conflicts is stronger in the Sahel region than in the rest of the sample. The paper identifies three main transmission channels through which conflict impedes renewable energy consumption: hindered economic development, increased military spending at the expense of green investment, and heightened uncertainty, which discourages investment and disrupts renewable energy production
RING dimerisation drives higher-order organisation of SINA/SIAH E3 ubiquitin ligases
No full textInternational audienceRING-type E3 ubiquitin ligases promote ubiquitylation by stabilising an active complex between a ubiquitin-loaded E2conjugating enzyme and a protein substrate. To fulfil this function, the E3 ubiquitin ligase SIAH1 and other SINA/SIAHsubfamily RING-type E3 ligases employ an N-terminal catalytic RING domain and a C-terminal substrate-binding domain (SBD), separated by two zinc fingers. Here, we present the first crystal structure of the RING domain of human SIAH1, together with an adjacent zinc finger, revealing a potential RING dimer, which was validated in solution using static light scattering. RING dimerisation contributes to the E3 ligase activity of SIAH1 both in vitro and in cells. Moreover, as the RING domain is the second element, after the SBD, to independently favour homodimerisation within SINA/SIAH E3 ligases, we propose that alternating RING:RING and SBD:SBD interactions organise multiple copies of a SINA/SIAH protein into a higher-order homomultimer. In line with this hypothesis, fluorescently-tagged full-length human SIAH1, human SIAH2, and fruit fly SINA show cytoplasmic clusters in human cells, whereas their distribution becomes more diffuse when RING dimerisation is disabled. The wild-type (WT) form of SIAH1, but not its RING dimerisation mutant, colocalises with aggregated synphilin-1A under proteasomal inhibition, suggesting that SIAH1 multimerisation might contribute to its reported preference for aggregated or multimeric substrates
Une définition de la fonction d'aspect de masse pour les variétés asymptotiquement hyperboliques peu régulières
No full textIn contrast to the well-known and unambiguous notion of ADM mass for asymptotically Euclidean manifolds, the notion of mass for asymptotically hyperbolic manifolds admits several interpretations. Historically, there are two approaches to defining the mass in the asymptotically hyperbolic setting: the mass aspect function of Wang defined on the conformal boundary at infinity, and the mass functional of Chruściel and Herzlich which may be thought of as the closest asymptotically hyperbolic analogue of the ADM mass. In this paper we unify these two approaches by introducing an ADM-style definition of the mass aspect function that applies to a broad range of asymptotics and in very low regularity. Additionally, we show that the mass aspect function can be computed using the Ricci tensor. Finally, we demonstrate that this function exhibits favorable covariance properties under changes of charts at infinity, which includes a proof of the asymptotic rigidity of hyperbolic space in the context of weakly regular metrics.Contrairement à la notion bien connue et non ambiguë de masse ADM pour les variétés asymptotiquement euclidiennes, la notion de masse pour les variétés asymptotiquement hyperboliques admet plusieurs interprétations. Historiquement, il existe deux approches pour définir la masse dans le cadre asymptotiquement hyperbolique : celle basée sur la fonction d'aspect de masse de Wang définie sur le bord conforme à l'infini, et celle de Chrusciel et Herzlich qui peut être considérée comme l'analogue asymptotiquement hyperbolique le plus proche de la masse ADM. Dans cet article, nous unifions ces deux approches en introduisant une définition de la fonction d'aspect de masse de type ADM qui s'applique à une large gamme d'asymptotiques et à une très faible régularité. En outre, nous montrons que la fonction d'aspect de la masse peut être calculée à l'aide du tenseur de Ricci. Enfin, nous démontrons que cette fonction présente de bonnes propriétés de covariance sous des changements de cartes à l'infini, ce qui inclut une preuve de la rigidité asymptotique de l'espace hyperbolique dans le contexte de métriques faiblement régulières
In-service teachers' perceptions of board games in teaching: Impact of the level of seriousness of the games and teachers' characteristics
No full textInternational audienceBoard games have become popular for teaching practices. Yet, factors of teachers' acceptance of board games remain unknown. In the present mixed-method cross-sectional survey study, 255 in-service French teachers were surveyed to examine the impact commercial-off-the-shelves and serious of board games, prior gaming experience, norms, and attitudes. Findings showed that teachers perceived more opportunities to learn for serious than for commercial-off-the-shelf board games. Attitudes had a positive impact on all variables and exerted a stronger impact than norms. Prior personal and professional gaming experience affected differently teachers' acceptance of board games. Educational implications for teachers' training programs are discussed
Scabiosa artropurperea var.maritima aqueous extracts improve in vivo fertility parameters and in vitro granulosa cell steroidogenesis in Ewe
No full textInternational audienceScabiosa artropurperea, a member of the Dipsacaceae family and Scabiosa genus, is renowned for its medicinal properties. In the present study, we investigated the impact of Scabiosa artropurperea aqueous extract (AES) on the in vivo reproductive functions in Queue Fine de l'Ouest ewes, and on in vitro ovine granulosa cells. Ewes were synchronized for 14 days with intra-vagina progesterone (P4) devices (FGA, 20 mg) and divided into four groups receiving daily oral doses of 0, 1, 2, and 4 mg of AES/kg Live Body Weight (LBW), respectively. After sponge removal, all ewes received an intramuscular injection of 400 IU of eCG. Estrous behavior parameters as latency and duration, and prolificacy rates, and plasma hormone levels (estradiol and progesterone) were assessed. Estrus latency was reduced and the duration of estrus was increased in ewes that received 1 mg and 2 mg/kg LBW compared to the control. Prolificacy rates were also significantly improved in 1 mg or 2 mg/kg groups compared to the control. Plasma levels of E2 were also higher on 2 mg/kg LBW treated group. Moreover, ovine granulosa cells were cultured and treated with various concentrations of AES (ranging from 0 to 5 mg/ml). While AES did not affect cell viability and proliferation whatever the conditions, it significantly increased basal steroidogenesis (P4 and E2 concentrations) at the concentration of 0.5 and 0.05 mg/ml and in response to IGF-1 but not FSH at the 0.05 mg/ml concentration. These latter data were associated to an increase in the expression of CYP19A1 and STAR genes but not those of CYP11A1 and HSD3B and to an increase in cellular lactate concentration. Taken together, AES extracts enhanced in vivo reproductive performance in ewe and this was associated to an increase in in vitro granulosa cell steroidogenesis