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Cultures et management international. Un nouveau paradigme
No full textInternational audienceLes managers internationaux sont sans cesse frappés par des réactions inattendues de leurs interlocuteurs locaux. Ces derniers ne sont pas moins perplexes. Chacun se doute qu’il est en présence de logiques qui lui sont étrangères, associées à des cultures qu’il peine à déchiffrer. Mais ce dont il s’agit leur paraît souvent bien opaque.Ce livre permet de passer de ce sentiment vague à une compréhension précise de ce que sont ces cultures et de la manière dont elles interviennent dans les multiples aspects de la vie d’une organisation. Diriger une équipe, gérer des clients, décider, apaiser les rapports sociaux, communiquer entre locuteurs de langues différentes ou mettre en oeuvre une démarche éthique porte partout la marque du contexte culturel.Cet ouvrage s’appuie sur un ensemble de recherches menées depuis quarante ans dans une cinquantaine de pays et territoires appartenant aux cinq continents, en partenariat avec de multiples entreprises. Chaque cas, qu’il analyse des malentendus destructeurs ou des coopérations fécondes, est riche d’enseignements. L’ensemble montre ce que peut apporter une prise en compte créative des potentialités de chaque culture qui ne se résume pas à des conduites stéréotypées mais relève d’un univers de sens plein de ressources
A phase inversion benchmark for multiscale multiphase flows
No full textInternational audienceA series of benchmarks based on the physical situation of “phase inversion” between two immiscible liquids is presented. These benchmarks aim at progressing towards the direct numerical simulation of two-phase flows. Several CFD codes developed in French laboratories and using either Volume-of-Fluid or Level-Set interface tracking methods are used to provide physical solutions of the benchmarks, convergence studies and code comparisons. Two typical configurations are retained, with integral scale Reynolds numbers of and , respectively. The physics of the problem are probed through macroscopic quantities such as potential and kinetic energies, or enstrophy. In addition, scaling laws for the temporal decay of the kinetic energy are derived to check the physical relevance of the simulations. Finally the droplet size distribution is probed. Additional test problems are also reported to estimate the influence of viscous effects in the vicinity of the interface
Modeling the debonding process of osseointegrated implants due to coupled adhesion and friction
No full textInternational audienceCementless implants have become widely used for total hip replacement surgery. The long-term stability of these implants is achieved by bone growing around and into the porous surface of the implant, a process called osseointegration. However, debonding of the bone-implant interface can still occur due to aseptic implant loosening and insufficient osseointegration, which may have dramatic consequences. The aim of this work is to describe a new 3D finite element frictional contact formulation for the debonding of partially osseointegrated implants. The contact model is based on a modified Coulomb's friction law (Immel et al, 2020) that takes into account the tangential debonding of the bone-implant interface. This model is extended in the direction normal to the bone-implant interface by considering a cohesive zone model, to account for adhesion phenomena in the normal direction and for adhesive friction of partially bonded interfaces. The model is applied to simulate the debonding of an acetabular cup implant. The influence of partial osseointegration and adhesive effects on the long-term stability of the implant is assessed. The influence of different patient-and implant-specific parameters such as the friction coefficient µ b , the trabecular Young's modulus E b and the interference fit IF is also analyzed, in order to determine the optimal stability for different configurations. Furthermore, this work provides guidelines for future experimental and computational studies, that are necessary for further parameter calibration
Games Where You Can Play Optimally with Arena-Independent Finite Memory
No full textInternational audienceFor decades, two-player (antagonistic) games on graphs have been a framework of choice for many important problems in theoretical computer science. A notorious one is controller synthesis, which can be rephrased through the game-theoretic metaphor as the quest for a winning strategy of the system in a game against its antagonistic environment. Depending on the specification, optimal strategies might be simple or quite complex, for example having to use (possibly infinite) memory. Hence, research strives to understand which settings allow for simple strategies. In 2005, Gimbert and Zielonka provided a complete characterization of preference relations (a formal framework to model specifications and game objectives) that admit memoryless optimal strategies for both players. In the last fifteen years however, practical applications have driven the community toward games with complex or multiple objectives, where memory -- finite or infinite -- is almost always required. Despite much effort, the exact frontiers of the class of preference relations that admit finite-memory optimal strategies still elude us. In this work, we establish a complete characterization of preference relations that admit optimal strategies using arena-independent finite memory, generalizing the work of Gimbert and Zielonka to the finite-memory case. We also prove an equivalent to their celebrated corollary of great practical interest: if both players have optimal (arena-independent-)finite-memory strategies in all one-player games, then it is also the case in all two-player games. Finally, we pinpoint the boundaries of our results with regard to the literature: our work completely covers the case of arena-independent memory (e.g., multiple parity objectives, lower- and upper-bounded energy objectives), and paves the way to the arena-dependent case (e.g., multiple lower-bounded energy objectives)
Fish gut-associated bacterial communities in a tropical lagoon (Aghien lagoon, Ivory Coast)
No full textInternational audienceAghien lagoon (Ivory Coast) is a eutrophic freshwater lagoon that harbors high biomasses of phytoplankton. Despite Increasing interest in fish gut microbiomes diversity and functions, little data is currently available regarding wild species from tropical west African lakes. Here, gut-associated bacterial communities are investigated in four fish species that are consumed by locale populations, namely the Cichlidae Hemichromis fasciatus , Tilapia guineensis and Sarotherodon melanotheron , and the Claroteidae Chrysichthys nigrodigitatus . Species-related differences are identified, that can be attributed to host phylogeny and diet. Important variations throughout the year are observed in T. guineensis and C. nigrodigitatus . This result emphasized the importance of time-series sampling and comparison with environmental variables even in tropical regions, that are not often conducted in wild populations. Effects of environmental factors (anthropogenic or not) on the microbiota and potential outcomes for fish health and populations sustainability need to be further explored. Interestingly, fish appear as major reservoirs of bacterial diversity, suggesting that they could contribute to the overall stability and resilience of bacterial communities present in the Aghien lagoon
A Century of Research on Psychedelics: A Scientometric Analysis on Trends and Knowledge Maps of Hallucinogens, Entactogens, Entheogens and Dissociative Drugs.
No full textInternational audienceA scientometric analysis was realized to outline clinical research on psychedelics over the last century. Web of Science Core Collection was searched up to March 18, 2022, for publications on psychedelics. Network analyses and bibliometrics were combined, to identify research themes and trends with Bibliometrix and CiteSpace. The primary aim was to measure research trends evolution over time, and the secondary aims were to identify bibliometric performance and influence networks of publications, authors, institutions, and countries. Sensitivity analyses were conducted for 2016-2022, and 2021 time periods. We included 31,687 documents (591,329 references), which aggregated into a well-structured network with credible clustering. Research productivity was split into an early less productive period mainly focusing on safety issues, and a "psychedelic renaissance" after the 1990s. Major trends were identified for hallucinogens/entheogens, entactogens, novel psychoactive substances (NPS), and on dissociative substances. There was a translational evolution from the bench to the bedside, with phase 2 and 3 trials and/or evidence synthesis in particular. The most recent trends concerned NPS, ketamine-associated brain changes, and ayahuasca-assisted psychotherapy. The USA and Canada were the most productive settings for the research overall, and more recently this geographical distribution became more prominent, reflecting legislative context/policy making. A translational evolution of psychedelics has been occurring, that has brought approval of esketamine for depression and will likely lead to approval of additional psychedelics across mental and physical conditions. Toxicology screening tools for NPS are urgently needed, which in turn might follow the same translational evolution of psychedelics in the future
sOilFauna -a global synthesis effort on the drivers of soil macrofauna communities and functioning
No full textInternational audienceUnderstanding global biodiversity change, its drivers, and the ecosystem consequences requires a better appreciation of both the factors that shape soil macrofauna communities and the ecosystem effects of these organisms. The project "sOilFauna" was funded by the synthesis center sDiv (Germany) to address this major gap by forming a community of soil ecologists, identifying the most pressing research questions and hypotheses, as well as conducting a series of workshops to foster the global synthesis and hypothesis testing of soil macrofauna. The overarching goal is to analyze the most comprehensive soil macrofauna databas
From Human-Nature Dualism Towards More Integration in Socio-ecosystems Studies
No full textInternational audienceSignificance Statement In the management of natural resources and biodiversity, humans and nature have traditionally been considered as two distinct systems, one controlling the other. The concept of socio-ecosystems allows a more integrated approach, in which humans and nature are recognized as interdependent. However, this new perspective does not necessarily eliminate a distinction between humans and nature, or even a hierarchy of humans over nature. This chapter aims to raise awareness of the potential human–nature dualism in socio-ecosystem approaches. Other research fields have adopted different approaches regarding human–nature integration versus dualism, offering a window on the advantages and limitations of various positions. We also discuss how methodological choices are important to translate human–nature integration or dichotomy depending on the study aim
