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Funérailles en lutte: Violences de masse et inhumations collectives en Europe et en Amérique latine
No full textInternational audienceThis work, the first ever dedicated to the study of mass funeral treatment, provides a comparative and critical analysis of the fate of human remains produced in contexts that share a history marked by the experience of armed struggles or extreme violence. How do funeral rituals unfold when there are dozens, hundreds, or thousands of bodies to bury simultaneously? Do ordinary ritual grammars remain operative? The European and Latin American cases addressed in this volume document collective burials and their political stakes in religious environments deeply influenced by the major monotheistic traditions, giving rise to symbolic practices embedded in a plurality of syncretic universes.Este trabajo, el primero dedicado exclusivamente al estudio de las inhumaciones colectivas, analiza de manera comparativa y crítica el destino de los restos humanos generados en contextos que comparten una historia marcada por la experiencia de conflictos armados o violencia extrema. ¿Cómo se desarrollan los rituales funerarios cuando hay decenas, cientos o miles de cuerpos que enterrar simultáneamente? ¿Siguen siendo operativas las gramáticas rituales ordinarias? Los casos europeos y latinoamericanos abordados en este volumen permiten documentar entierros colectivos y sus implicaciones políticas en entornos religiosos profundamente influidos por las grandes tradiciones monoteístas, dando lugar a prácticas simbólicas inscritas en una pluralidad de universos sincréticos.Cet ouvrage, le premier jamais consacré à la question du traitement funéraire de masse, analyse de façon comparative et critique la destinée des restes humains produits dans des contextes qui partagent une histoire marquée par l’expérience des luttes armées ou de la violence extrême. Comment se déroulent les rituels funéraires lorsqu’il y a plusieurs dizaines, centaines ou milliers de corps à inhumer simultanément ? Les grammaires rituelles ordinaires sont-elles toujours opérantes ? Les cas européens et latino-américains abordés dans ce volume permettent de documenter des funérailles collectives et leurs enjeux politiques dans des environnements religieux durablement empreints des grands monothéismes, ouvrant sur des pratiques symboliques inscrites dans une pluralité d’univers syncrétiques
Transversely isotropic hyperelastoplastic constitutive model for large deformation analysis and simulation of fiber yarns and stranded ropes
No full textInternational audienceThe mechanical behavior of fibrous structures, such as composite reinforcements and synthetic ropes, is characterized by large deformations and complex anisotropic responses. Traditional models, predominantly based on elastic formulations, fail to adequately capture the deformation history and dissipative mechanisms observed in these systems. This study introduces a novel hyperelastoplastic framework tailored for fibrous media, incorporating a new family of invariants that account for the deformation history in the model, beyond the limitations of classical invariants. These advanced invariants enable a more accurate description of the mechanical response under large deformation, particularly in matrix-free mesoscopic architectures where fiber sliding, friction, and transverse compression dominate. The proposed approach is demonstrated to be equally applicable to the mesoscopic modeling of composite reinforcements and stranded ropes, offering improved predictive capabilities for their structural behavior and long-term performance under complex loading conditions
Effect of hydrolytic ageing on the fracture properties of repaired carbon/polyamide 6 thermoplastic composites
No full textInternational audienceThis study investigates the repair potential of carbon/polyamide 6 specimens after extensive hydrolytic degradation, using double cantilever beam (DCB) characterization. To evaluate repair effectiveness, DCB test results from repaired specimens were compared with those from aged but unrepaired specimens. The results indicate a reduction in mode I fracture toughness G IC for most repaired specimens compared to their unrepaired counterparts (from 3.44 kJ/m 2 down to 0.94 kJ/m 2 in the non-repaired state compared to 2.44 kJ/m 2 down to 0.84 kJ/m 2 in the repaired condition). However, as ageing duration increased, the difference in G IC values between repaired and unrepaired specimens progressively decreased, eventually converging for the longest ageing duration studied (from −29% in the unaged state down to −10% for the ultimate degradation duration). To understand this behaviour, complementary analyses, including molar mass and crystallinity ratio measurements, X-ray tomography, and SEM observations, were conducted. These investigations suggest that fibre misalignment and a weakened fibre/matrix interface after repair contributed to the observed reduction in G IC for a given ageing duration. While prior studies have addressed the repair of thermoplastic composites, the effect of hydrolysis on their repairability remains largely unexplored. This work highlights the repair potential of thermoplastic composites even after significant irreversible degradation
Core Monitoring of Thermoset Polymer Composites’ Curing with Embedded Nanocomposite Sensors: A Key Step Towards Process 4.0
No full textInternational audienceStructural composite materials are being used more than ever in aeronautics, automotive and naval, or in renewable energies fields. To reconcile the contradictory needs for higher performances and lower costs, it is crucial to ensure the real-time monitoring of as many features as possible during the manufacturing process to feed a digital twin able to minimise post-fabrication controls. For thermoset composites, little information is available regarding the evolution of the polymer’s core properties during infusion and curing. The local kinetics of reticulation, in several areas of interest across the thickness of a structural composite part, are valuable data to record and analyse to guarantee the materials’ performances. This paper investigates a novel strategy curing in the core of an epoxy matrix with crosslinkable quantum-resistive nanocomposite sensors (xQRS). First, the electrical behaviour of the sensor during isothermal curing is considered. Then, the influence of the dynamic percolation and the epoxy crosslinking reaction on the resistance is examined. The evidence of a relationship between the curing state of the resin and the evolution of the xQRS resistance makes its use in the process monitoring of thermoset composites promising, especially in cases involving large and thick parts
Les livres à venir : la bibliothèque « virtuelle » de François Grudé de La Croix du Maine
No full textInternational audienc
L'insubordination hiérarchique répétée ne constitue pas à elle seule un harcèlement moral
No full textInternational audienceNote sous CAA Versailles, 22 novembre 2024, no 22VE0222
Geographic Genetic Divergence in Tychoplanktonic Taxa Dominating Diatom Communities in Marine Biofilms
No full textInternational audienceDiatoms constitute the main photosynthetic group in marine biofilms throughout the world's oceans, in particular, on plastic debris, which has become a major problem in the marine environment. However, they remain largely unexplored in this context compared to prokaryotes. Here, we aim to understand the dynamics of diatom communities in the plastisphere at different levels: how taxa are selected from the planktonic community and how communities are structured over time and at large spatial scales. Biofilms were collected from PVC (polyvinyl chloride) panels immersed (i) for 1 year in two NW Mediterranean sites, a mesotrophic one (Toulon Bay) and an oligotrophic one (Banyuls Bay), and (ii) for 1 month in Toulon Bay and two other eutrophic sites (Lorient in South Brittany in the Atlantic Ocean and Reunion Island in the Indian Ocean). Plastispheres were analyzed using both microscopic and molecular approaches, focusing on the relationship between diatoms and other microorganisms in biofilms. Light microscopy revealed spatio-temporal differences in cell abundance and biovolume. Metabarcoding, targeting the rbcL gene for diversity and composition, revealed that the richness of diatom species was already maximal in the early stages of biofilm formation, and beta-diversity showed a clear temporal evolution in the Mediterranean Sea. Including prokaryotic and fungal communities, we described microorganism interactions within biofilms throughout the colonization process of the plastisphere. In addition, environmental parameters on a large geographical scale were shown to be stronger drivers in structuring diatom communities, considering both planktonic and biofilm lifestyles. A core biofilm community represented by a few abundant species was observed across sites. The occurrence of tychoplanktonic taxa emphasizes the specificity of diatoms among other microorganisms in biofilms. Finally, the complete absence of common genetic variants among Lorient, Reunion Island, and Toulon suggests that dispersal by marine currents over a large geographical scale has led to adaptation processes. | IntroductionDiatoms are unicellular photosynthetic microeukaryotes, which are distributed across marine, freshwater, and terrestrial ecological niches, contributing up to 20% of the global primary production, including roles in carbon fixation and nutrient cycling (Benoiston et al. 2017; Tréguer et al. 2018). Most information is based on their planktonic lifestyle (e.g., MalviyaThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.</div
Case-Based Simulation to Support Complex Active Catheterization: Preliminary Results
No full textInternational audienceObjective: Active catheters are intended to support endovascular navigation in complex anatomies. Nevertheless, their configuration and utilization are challenging. Finite element (FE) modeling representing the navigation of active guidewires alongside catheters can be considered at an early stage to identify the best parameters and support physicians in their planning and procedure. However, FE simulations require significant computation time. We introduce the concept of case-based simulation (CBS) to quickly find adequate configuration parameters for complex catheterization scenarios. Method: Combining case-based reasoning and FE simulation, CBS approach is considered to reuse design and navigation parameters from previous simulations. A case base is made of successful catheterization simulations performed on reference aorta geometries. For a new patient, a distance metric based on a statistical shape model is used to determine appropriate catheterization parameters from previously simulated cases. The proof-of-concept of this method is performed in the case of the navigation from the aortic arch to the left carotid artery. Among 11 patient-specific aortic arches, three were selected for the reference FE simulations of the left carotid artery hooking to constitute the case base and three others were selected for evaluation
Application of Model Predictive Control to reconfigurable propulsion AUVs for task-based adaptation: Learning Autonomous Mobility of Underwater Robots for Renewable Energies (PhD Thesis)
No full textNational audienceAutonomous underwater robots (AUVs) offer a promising solution for the inspection and maintenance of marine renewable energies, but the complexity of marine environments imposes meaningful challenges in terms of mobility, control, navigation and the performance of complex tasks operations. The proposed solution is to create a robot with reconfigurable thrusters patterns that would enable it to move in all 6 degrees of freedom, albeit not simultaneously, while keeping the number of thrusters below the usual required 6. This increased mobility require advanced control schemes and this work focuses on the application of model predictive control (MPC) method as proof of concept for reconfigurable AUVs controllability during task-based propulsion adaptation
Effet du type de courant sur la dégradation des électrodes lors du soudage par résistance par point
No full textInternational audienceEffet du type de courant sur la dégradation des électrodes lors du soudage par résistance par poin