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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
Le quartier du Fort à Saint-Benoît-du-Sault (Indre), résultats du diagnostic d’archéologie préventive de novembre 2020. Première partie : les questions d’urbanisme
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Marek’s Disease Virus Replication in Chicken Skin Reconstructed In Vitro: Evidence for Viral Particles in Corneocytes
No full textInternational audienceMarek’s disease (MD) is a lethal lymphoma of chickens, which is caused by MD virus (MDV), an alphaherpesvirus. MDV infects epithelial cells of the skin appendages, notably feather follicles, replicates in these cells and is shed into the environment exclusively from these tissues. Here, we tested whether chicken skin equivalents (SEs) can be used to model MDV infection. Primary chicken keratinocytes were seeded on a suspension of fibroblasts in collagen and induced to terminally differentiate at the air-liquid interface. A recombinant MDV expressing the Katushka fluorescent protein (MDV-KAT) was introduced into SEs by seeding of primary keratinocytes together with MDV-KAT-infected keratinocytes of the K8 cell line. KAT-mediated fluorescence increased during the culture of infected SEs, indicating virus infection and replication, while the expression of keratinocyte differentiation markers was not significantly altered by MDV infection. MDV did not spread to the dermal compartment of SEs, but localized to the upper layers of the epidermis. Viral particles were readily observed by electron microscopy in living keratinocytes and for the first time in cornified keratinocytes of the outermost layer of infected SEs, evidence for excretion of viral elements into environment. Finally, we demonstrated that two fluorescent vaccine strains of MDV, Rispens and herpesvirus of turkey, can infect and replicate in SEs. Taken together, this study establishes chicken SEs as an in vitro model for MDV infection
Les savoirs expérientiels à l'épreuve de la validation : procédés narratifs et modes d'existence
No full textInternational audienceFrom the perspective of candidates for the validation of prior learning (VAE), formalizing their practice in written texts in order to convey, through oral and written expression, the knowledge acquired at work and throughout their professional life requires learning to narrate, describe, and conceptualize. Similarly, from the perspective of jury members, assessing and validating experiential knowledge to grant certification requires stabilizing definitions, criteria, and a logic that enables the deliberation processes of the jury to be based on a structured framework. More than twenty years after the implementation of prior learning validation systems in France and Europe, these definitions and methods have yet to be fully developed. The reflection carried out in this text examines the various dimensions of the issue related to the formalization and assessment of experiential knowledge, based on questions that intersect epistemological, theoretical, and methodological dimensions.Du point de vue des candidats à la validation des acquis de l’expérience (VAE), formaliser sa pratique dans des textes afin de faire connaître, par l’expression orale et écrite, les savoirs acquis au travail et au cours de la vie professionnelle, suppose, d’apprendre à raconter, décrire et thématiser. De même, du point de vue des membres du jury, évaluer et valider des savoirs expérientiels pour délivrer une certification suppose de stabiliser des définitions, des critères et une logique permettant d’adosser les processus de délibération du jury à un dispositif stabilisé. Plus de vingt ans après la mise en œuvre des dispositifs de validation des acquis de l’expérience, en France et en Europe, ces définitions et méthodes restent à produire. La réflexion conduite dans ce texte examine les différentes dimensions de la problématique relative à la formalisation et à l’évaluation des savoirs expérientiels, à partir d’interrogations qui croisent les dimensions épistémologiques, théoriques et méthodologiques