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Je passe au vert mais… : le cas des fournisseurs d’énergie verte
No full textInternational audienceEn analysant 13 141 avis de clients de fournisseurs d'énergie verte et 13 173 avis de fournisseurs d'énergie traditionnelle en France, nous avons examiné le rôle des attributs écologiques dans la satisfaction globale à l'aide de trois méthodes d'analyse textométrique (Latent Dirichlet Allocation, Méthode de Reinert et Approche Sémantique). Nos résultats révèlent que le service client est le principal facteur de satisfaction pour les fournisseurs d'énergie verte, la qualité du service jouant un rôle important dans la formation des niveaux de satisfaction. Les facteurs neutres, tels que la surveillance de la consommation et la facturation, ont un impact minimal, tandis que la tarification et les hausses de prix tendent à réduire la satisfaction. Trois éléments spécifiques aux fournisseurs d'énergie verte — les avantages financiers des programmes de parrainage, l'expérience de l'interface utilisateur et les attributs écologiques (par exemple, l'énergie locale et renouvelable) — sont associés à des consommateurs hautement satisfaits. Contrairement aux études précédentes, nos résultats indiquent que bien que les facteurs écologiques soient idéologiquement attractifs pour les consommateurs, ils ne sont pas les plus importants, car d'autres facteurs, tels que la qualité du service et les incitations financières, jouent un rôle plus significatif dans l'influence de la satisfaction des clients
Identification of material properties from impedances in Spinal Cord Stimulation (SCS) using computational models.
No full textInternational audienceSpinal Cord Stimulation (SCS) is an effective therapy to manage refractory chronic pain (Duarte et al., 2020). SCS consists in delivering electrical field targeting the dorsal column fibers of the spinal through a lead array implanted in the epidural space. Thereby, the activation of the dorsal column fibers triggers the inhibitory interneurons as described in the Gate Control theory (Melzack & Wall, 1965). Computational modelling represents a promising avenue to better understand the target of the electrical field to the dorsal column fibers of the spinal cord. Previous studies rely on a 2-step simulation. First, the electrical field is computed through the Finite Element Method (FEM) at the spine segment scale, with the quasistatic assumption often made. Then, the result of the first simulation was used in a second simulation at the neuron scale to get insight into the electrophysiologicalbehavior of the neural elements of interest (namely, dorsal columns and dorsal root axons, neurons of the dorsal root ganglion and dorsal horn).A recent systematic review, synthesizing the available models in the literature (Liang et al., 2022), high- lighted controversy about some parameters, such asthe dura-mater resistivity (Zander et al., 2020). In our study, we investigated the relationship between impedance measurements (which are routinely obtained in patients with implanted lead array during follow-up visits) and parameters of the finite-element models to validate the simulation
Mechanical behavior characterization of glioblastoma cell using Scanning Ion Conductance Microscope (SICM)
No full textInternational audienc
Effects of thermopriming and bacteria-mediated heat-stress acclimation strategies on seed yield and quality criteria in Brassica napus cv Aviso and Camelina sativa cv Calena
No full textInternational audienceThe effects of intense heat during the reproductive phase of two Brassica species-B. napus and C. sativa-could be alleviated by a prior gradual increase exposure and/or PGPR inoculation. Abct. Among extreme weather events caused by climate change, heat waves are one of the most threatening issues for food security. Heat stress is known to be particularly penalizing at the reproductive stage for oleaginous crops, such as oilseed rape and camelina, and is responsible for crop failures as a consequence of yield losses and lower quality of harvest plants parts. In this context, our study aims to analyze two acclimation strategies that rely on the induction of signals prior to an intense heat stress event, i.e., thermopriming (herein, a gradual increase in temperature) and bacteria inoculations (herein, two Plant Growth-Promoting Rhizobacteria (PGPR) were tested). In the two experiments, we assessed the expected beneficial effects of these two acclimation strategies on yield components, seed quality criteria (nutritional and related to dormancy). While thermopriming improved heat stress tolerance in B. napus cv Aviso by maintaining yield, seed nutritional quality and seed dormancy, the effects of the gradual increase prior to the heat stress were even more negative than the later intense heat stress event in C. sativa cv Calena which resulted in cumulated negative effects. The experimentation based on PGPR inoculation highlighted similar trends to thermopriming in B. napus cv Aviso but to a lesser extent. However, in C. sativa cv Calena, very weak effects of PGPR inoculation upon heat stress were observed. Finally, these two acclimation strategies were shown to help alleviate the impacts of intense heat stress but in a species-dependent manner. This study should be deepened by exploring the behaviors of more cultivars of oilseed rape and camelina in the perspective to generalize these results at the species scale
Semi-linear fractional boundary values problems and green functions
No full textWe introduce and analyze semi-linear fractional dierential equations supplemented with general linear homogeneous boundary conditions. Problems tractable by xed points methods are characterized at an abstract level by using a recent unied theory of the author. This lead to the concept of Green functionals which in application yields to Green functions. Quantitative (existence and/or uniqueness) and positivity results are obtained for a large class of (fractional) dierential operators encompassing generalized Caputo and Riemann-Liouville derivatives. For the convenience of the reader, a simple example will be treated in Section 4
Extensive environmental survey of free-living amoebae and their elusive association with Mycobacterium bovis or Mycobacterium avium subsp. paratuberculosis
No full textInternational audienceFree-living amoebae (FLA) are described as environmental reservoirs for some bacteria able to resist their phagocytosis. In the environment, the fate of Mycobacterium bovis (Mbo) and Mycobacterium avium subsp. paratuberculosis (Map) responsible for bovine tuberculosis and paratuberculosis, respectively, remains poorly understood and is considered potentially problematic in the eradication and control of these diseases. We hypothesize that FLA may play a role in the persistence of Mbo and Map in the environment. In this study, 90 samples were collected from herds affected by one or both diseases to investigate the diversity of amoeba and their associated bacteria. Metabarcoding analyses revealed that Acanthamoeba, Copromyxa, Naegleria, and Vermamoeba were the most represented genera of FLA, with Pseudomonadota being the bacteria most commonly found associated with FLA. Although no Mbo and Map DNA were identified by sequencing, traces were detected by ddPCR (digital droplet PCR), specifically targeting these bacteria. In conclusion, we described a wide diversity of FLA and associated bacteria in this environment. It also suggests that Map and Mbo could be associated, even weakly, with FLA in the environment. However, this needs to be confirmed by detecting a highest amount of DNA and, if possible, cultivable Map and/or Mbo associated with these environmental FLA
It is not only whether I approach but also why I approach: A registered report on the role of action framing in approach/avoidance training effects
No full textInternational audienceResearch on approach/avoidance training (AAT) effects shows that approach (i.e., reducing the distance between the self and a stimulus) leads to more positive evaluations of stimuli than avoidance (i.e., increasing the distance between the self and a stimulus). The present experiments relied on a grounded cognition approach to extend this finding by investigating the framing-dependency of AAT effects on facial representations of target stimuli. In a Preliminary Experiment, using antagonistic types of approach (affiliative vs. aggressive) and a reverse correlation paradigm, we found that approach led to more positive facial representations than avoidance when approach was portrayed as affiliative, but this effect decreased and tended to reverse (i.e., yielding more negative facial representations) when approach was portrayed as aggressive. Two registered experiments extended these results while also addressing important limitations of the Preliminary Experiment. First, to prevent any contrast emerging from the joint use of approach and avoidance, Experiment 1 isolated the unique effects of affiliative approach, aggressive approach, and avoidance compared to a control action. We also explored whether aggressive approach and avoidance (two negatively valenced yet distinct actions) produced negative effects characterized by divergent outcomes on facial features (e.g., weak vs. dominant). Second, Experiment 2 tested the importance of the experiential component of approach/avoidance actions by comparing the AAT with a mere instructions condition. Results of Experiments 1 and 2 proved consistent with a framing-dependency of AAT effects. Unveiling the framing-dependency of AAT effects challenges some of the current theoretical views on AAT effects
All-around local structure classification with supervised learning: The example of crystal phases and dislocations in complex oxides
No full textTo accurately identify local structures in atomic-scale simulations of complex materials is crucial for the study of numerous physical phenomena including dynamic plasticity, crystal nucleation and glass formation. In this work, we propose a data-driven method to characterize local atomic environments, and assign them to crystal phases or lattice defects. After constructing a reference database, our approach uses descriptors based on Steinhardt's parameters and a Gaussian mixture model to identify the most probable environment. This approach is validated against several test cases : polymorph identification in alumina, and dislocation and grain boundary analysis in the olivine structure
Le contrat collectif en agriculture
No full textInternational audienceL'agriculture est un terreau fertile en contrats divers et variés. Le format contractuel interindividuel, qui lie deux parties, y est la norme. La figure du contrat collectif émerge cependant pour embarquer des communautés d'agriculteurs et faire face à des problématiques plus larges de transition du modèle agricole. Mais que recouvre cette contractualisation collective ? Et quelles difficultés techniques cache-t-elle ? Derrière cette réflexion, l'enjeu est de déterminer si une version collective du contrat peut devenir un élément clé d'accompagnement des politiques agricoles
Cultural Barriers to Women's Progression in Academic Careers: A France‐Brazil Comparison Through the Lens of the Queen Bee Phenomena
No full textInternational audienceDespite significant improvements, women are still underrepresented at high levels in academia. Most research on these inequalities is conducted within a specific national academic system, without taking into account its cultural roots. The aim of the present study was to analyze the extent to which the cultural context acts as a barrier on women's career progression. Specifically, we focused on psychological processes described under the metaphor of Queen Bee Phenomenon that may reflect the ways in which female academics conform to male-gender roles encoded in androcentric social and academic culture. Two samples of women academic, one French (N = 73), the other Brazilian (N = 88), were compared through the lens of two dimension of the Queen Bee Phenomena: self-group distancing and gender hierarchy legitimation. Brazilian women identify more with their female peer group than their French counterparts. French women are more hostile to quotas and more inclined to adhere to meritocratic discourses than their Brazilian counterparts. Both academic contexts tend to perpetuate gender inequalities, but in different ways: by maintaining gender-stereotypical expectations in Brazil and meritocratic ideology in France. The implications for policies to promote a more egalitarian university context are discussed herein