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Structuring and enriching the rearing environment in conventional broiler chicken production: effects on behavioral indicators, emotional states, and cecal microbiota composition
No full textInternational audienceProviding a variety of elements in the rearing environment may offer a promising way to transition conventional broiler production towards more animal-friendly production systems. This study aimed to investigate the effect of a complex and structured rearing environment on broiler welfare by comparing three complex enriched rooms (E) with visual cues and multiple elements for resting or exploration, to three control rooms (C) with minimal enrichments. Each room housed 2450 Redbro chickens and received natural light. We evaluated how the rearing environment influenced chicken behavior, emotional state, and the cecal microbiota composition at the end of the rearing period. E chickens stood, foraged and moved more often than C chickens (e.g. 38% vs. 19% walking; 4% vs. 1% foraging, P < 0.001), while dustbathing frequency did not differ. In group-based tests, E chickens were more likely to approach and peck at a novel object or human (P < 0.05), suggesting reduced fearfulness and increased curiosity. In the detour test, E chickens exited the U-shaped area more frequently (P < 0.001) and vocalized less (P = 0.004), indicating greater exploratory motivation and possibly better spatial cognition. Microbiota analysis revealed no differences in alpha diversity, but beta diversity differed significantly between treatments (P < 0.001). E chickens had higher relative abundances of Bacteroidota, while C chickens had more Bacillota. Overall, the complex environment promoted natural behaviors, reduced emotional reactivity, and altered gut microbiota composition, supporting its potential to improve broiler welfare under semi-commercial conditions
Investigation of the structural properties of BiCuTaVOx compounds with improved oxygen ion conductivity and photocatalytic degradation of SMX
No full textInternational audienceThis study aimed to enhance the performance of Bi4V2O11 by synthesizing compounds with double substitution using (Cu2+) and (Ta5+) ions and investigating their photocatalytic activity. Bi4V2-xCux/2Tax/2O11-3x/4 (0.1 ≤ x ≤ 0.5) samples were prepared using a solid-state reaction. X-ray diffraction (XRD) analysis showed stabilization of the tetragonal γ-Bi4V2O11 phase for x = 0.2–0.4. These findings were corroborated by differential thermal analysis (DTA), Fourier-transform infrared (FT-IR), and Raman spectroscopy. Scanning electron microscopy (SEM) was employed to investigate microstructure and grain size. Temperature-dependent Raman spectroscopy revealed structural changes in α-BiCuTaVOx (x = 0.1) due to thermal effects. Electrochemical impedance spectroscopy (EIS) was used to evaluate electrical conductivity. Bandgap energies were measured using UV-visible diffuse reflectance spectroscopy. The photocatalytic activity was studied by comparing simple and double substitutions of Cu2+ and Ta5+. A synergistic effect was observed in the photodegradation of sulfamethoxazole (SMX). The sample with x = 0.3 showed the best photocatalytic activity and conductivity (σ600 °C = 4 × 10−3 S cm−1)
The pUL47 tegument protein of Marek’s Disease Virus interacts with p32/C1QBP to promote horizontal transmission: Role of the pUL47 /p32 interaction in MDV transmission
No full textInternational audienceInter-individual transmission is an essential part of viruses’ life cycle, yet the molecular basis of transmission remains elusive. Using Marek’s Disease Virus (MDV), a deadly and contagious herpesvirus of chickens that is transmitted by inhalation of contaminated dander, we previously demonstrated that tegument protein pUL47 was necessary for horizontal transmission in the natural host while being dispensable for pathogenesis and replication. We showed that pUL47 was also necessary for the correct splicing and expression of UL44 transcripts, which encode glycoprotein gC, another viral protein known as essential for MDV’s transmission. Here, with the aim of characterizing the molecular basis for the role of pUL47 in transmission, we identify the cellular protein p32/C1QBP / gC1qR, a regulator of mRNA splicing, as a binding partner. We demonstrate that this interaction is necessary for transmission while being dispensable for the correct splicing and expression of UL44 transcripts, thus uncoupling the role of pUL47 in transmission from gC. These results provide a deeper molecular understanding of the natural transmission of a Herpesvirus
Le rôle des insectes dans la durabilité agroalimentaire : tirer parti des services écosystémiques pour parvenir à une gestion intégrée des insectes
No full textInternational audienceThe global agrifood system faces complex challenges related to biodiversity loss, food insecurity, and environmental degradation. Insects, as providers of multiple ecosystem services, offer a largely untapped potential to contribute to sustainability. This article introduces a conceptual framework for understanding the socio-ecological roles (SER) of insects, encompassing not only provisioning, regulating, supporting, and cultural services, but also the risks and challenges associated with their use and management. Through an interdisciplinary synthesis, we analyse four complementary insect management strategies—conservation, pest and vector control, wild insect gathering, and insect farming—and examine the relationship of these strategies to ecosystem services and stakeholder dynamics, as well as the need for policies regulating insect use and conservation. We argue that combining these strategies rather than treating them as isolated approaches enhances the capacity to optimize insect contributions while mitigating trade-offs. This holistic perspective contributes to a systemic, inclusive, evidence-based foundation for decision-making regarding the use of insect biodiversity to achieve resilient, sustainable agrifood systems
Présentation du livre “Noble Magnificence. Culture of the Performing Arts in Rome 1644-1750», co-édité avec Michela Berti, Biblioteca Nazionale, Florence
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Firewall boundaries and mixed phases of rotating quark matter in linear sigma model
No full textInternational audienceA rigidly rotating body in unbounded space is usually considered a pathological system since it leads to faster-than-light velocities and associated breaches of causality. However, numerical results on chiral symmetry breaking in rotating plasmas of interacting fermions reveal surprisingly close correspondence in predictions between rigorous bounded and formal unbounded approaches. To provide insight into this correlation, we consider the linear sigma model coupled to quarks, undergoing rigid rotation in unbounded Minkowski space-time. Within the mean-field approach, we adopt three consecutive levels of approximation to the ground state of the system that feature a uniform (model 1), weakly-inhomogeneous (model 2) and fully inhomogeneus (model 3) condensates. Models 1 and 2 that do not take into account spatial gradients of the condensate, show agreement with the Tolman-Ehrenfest law. Model 3 exhibits a deviation from the Tolman-Ehrenfest prediction due to the appearance of a new energy scale set by the inhomogeneity of the ground state. Its boundary conditions are fixed by imposing regularity at the rotation axis and by demanding the global minimization of the grand potential. We dub the latter as "firewall boundary conditions," translating into the requirement of vanishing condensate on the light cylinder, which follows from the fact that the system state formally diverges at the light cylinder. In all models, we present the phase diagram of the system and point out that in models 2 and 3, the system resides either in a chirally-restored phase, or in a mixed phase that possesses spatially-separated chirally-restored and chirally-broken phases
Vortex wall phase in fractonic XY-plaquette model on square lattice
No full text15 pages, 6 figuresInternational audienceThe XY-plaquette model is the most straightforward lattice realization of a broad class of fractonic field theories that host quasiparticles with restricted mobility. The plaquette interaction appears naturally as a ring-exchange term in the low-energy description of exciton Bose liquids, cold atomic gases, and quantum dimer models. Using first-principle Monte Carlo simulations, we study the phase diagram and the vortex dynamics in the XY-plaquette model on a square lattice in two spatial dimensions. In its minimal formulation, the model contains a ring-exchange plaquette term in two spatial dimensions and a standard XY-link term in the (imaginary) time direction. We show that the phase diagram of the minimal XY-plaquette model possesses two phases: (i) a disordered vortex-dominated phase in which a single percolating vortex trajectory occupies the whole 3d spacetime; (ii) a partially disordered phase in which the vortices become partially immobile, with their worldlines strictly confined to one or several infinite two-dimensional planes. The spatial positions and spatial orientations (along or axis) of these vortex domain walls appear to be spontaneous. Individual vortices form a disordered system within each vortex domain wall, so the fractal spacetime dimension of vortex trajectories approaches . We argue that the appearance of the vortex walls could be interpreted as a consequence of the spontaneous breaking of a global internal symmetry in the compact XY-plaquette model
Closed-form solution and reliability analysis of deep lined tunnel behavior in anisotropic viscoelastic rock
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Vulnérabilité en situation
No full textInternational audienceOriginally intended to protect people in fragile situations, the concept of vulnerability has become so prevalent in political, social and scientific discourse that it risks losing its operational value. It was thus necessary to clarify the social implications and linguistic issues involved, by conducting research in settings where people considered to be vulnerable are concentrated (prisons, hospitals, medical-social institutions, etc.).The contributions to this book study situations in which people encounter difficulties related to illness, dependence, exclusion, social invisibility or precariousness. The discursive modalities through which vulnerability is created, transformed or exacerbated in our social relations were examined, with the hope of contributing to the emergence of other forms of social ties or solidarity.Catégorie destinée à l’origine à protéger les personnes en situation de fragilité, la vulnérabilité a tellement investi les discours politiques, sociaux et scientifiques qu’elle court le risque de perdre sa valeur opératoire. Il était donc nécessaire d’en préciser les enjeux sociaux et langagiers, en enquêtant dans des lieux regroupant des publics considérés comme vulnérables (prison, hôpital, établissement médico-social…).Les contributions de cet ouvrage ont étudié les situations dans lesquelles des personnes rencontrent des difficultés liées à la maladie, la dépendance, l’exclusion, l’invisibilité sociale ou la précarité. Ont été scrutées les modalités discursives par lesquelles se crée, se transforme ou s’exacerbe la vulnérabilité dans nos relations sociales – en espérant ainsi contribuer à faire exister d’autres formes de lien social ou de solidarité
COTLEA: COpula-based Transfer Learning Evolutionary Algorithm for Multi-Objective Optimization Problems
No full textInternational audienceA major assumption often made during the resolution of NP-Hard Multi-Objective optimization Problems is that problem instances are different from each other. Then, the same process is repeated integrally to solve these instances without benefiting from prior resolutions of similar problem instances. Consequently, resolution systems lose a lot of time to solve problems that were already partially or integrally treated beforehand. In this paper, we assume that previous Pareto Front solutions can guide new problem instance resolutions to accelerate the convergence to the optimal solutions. According to this assumption, our objective is to propose a framework that first learns a feature model on the previous solutions and second integrates this model in the resolution process. To this end, we introduce a new heuristic, called COTLEA, for COpula-based Transfer Learning Evolutionary Algorithm. COTLEA is a simple and fast transfer learning framework that incorporates a Copula model to learn the feature representation of a source problem and uses an evolutionary algorithm to make the transfer of knowledge. The empirical study of our proposal shows significant performance in terms of convergence speed compared to typical evolutionary approaches