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De Booba à Indexia : ce que les scandales révèlent des angles morts de la recherche en management
No full textInternational audienceÀ partir des scandales Booba et Indexia, ce texte explore les angles morts de la recherche en management. Il met en évidence les limites épistémologiques, méthodologiques, conceptuelles et éthiques qui empêchent la discipline de penser les phénomènes émergents, ambivalents ou déviants, en dépit de leur impact sociétal parfois considérable. En dialogue avec les travaux critiques récents, il propose des pistes pour renouveler les objets, les méthodes, les engagements et la formation en management, afin de proposer une autre conception de la responsabilité académique
Rapport 2025 du Haut comité de gouvernement d'entreprise
No full textInternational audienceRapport du Haut comité de gouvernement d'entreprise et Guide d'application du code AFEP-MEDEF de gouvernement d'entreprise des sociétés cotées, décembre 202
Was calcareous tufa deposition related to the forest cover during the Holocene? A GIS investigation
No full textInternational audienceSince the end of the last century, studies of paleoenvironments and paleoclimate have increasingly focused on calcareous tufas. Previously, it was assumed that their formation was related to climate and environmental changes, particularly changes in forest density. However, this has yet to be demonstrated. A dataset of 579 Holocene tufas was used to analyze the spatial and temporal distribution of European tufas in relation to forest density. During the Holocene, tufas were located in areas that were fairly well forested. During the Preboreal and Boreal periods, they formed in areas with a higher forest cover than the European average, mostly in the lowlands of north-west Europe. Thus, during these periods, significant forest density appears to be a key contributor to tufa development. Until the Subatlantic, the forest density covering tufa areas (40-75%) matched that of Europe's most forested areas, with tufas being more widespread. Therefore, while significant forest coverage is necessary, it should not be overly dense. Currently, the average forest density in tufa areas (28-42%) is similar to the European average forest cover, suggesting that now their development is no longer correlated with forest density. We hypothesized that other factors could impact tufa development such as the fire regime and its reflect on different forest species and differences in topographical position. Finally, we wanted to highlight the importance of inventories in understanding the mechanisms of tufa development, which is essential for protecting active sites
SOMALIE : TRENTE ANS D'INTERVENTIONS MILITAIRES SANS RÉSOLUTION: De l'AMISOM à l'AUSSOM, quand la reconquête territoriale ne suffit pas à reconstruire l'État (2006-2025)
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Converting Liminal Uncertainty into Collective Agency: A Futures Literacy Lab in Maré, Rio de Janeiro
No full textFutures literacy is more than a pedagogical tool for enhancing people’s perceptions of the various anticipatory systems and processes. When embedded in a process to promote social recommitment and social transformation, it converts liminal uncertainty into collective agency. This study shows the case of Conjunto de favelas da Maré (Rio de Janeiro) – through Redes da Maré (NGO) – where communities exposed to a state of permanent crisis struggle to move from recognizing challenges to taking action. We ask how a Futures Literacy Laboratory (FLL) can be designed and evidenced so that community imaginaries travel beyond workshops into agendas, roles, and institutional footholds. Using participatory action research, we co-led a UNESCO-type FLL in Maré (Nov 2023–Jul 2024) with ~30 residents and staff; data included workshop artefacts, transcripts, field notes, and participant reflections. The contribution is interpretive and methodological: a gated six-stage cycle specifies checkpoints and roles, showing how shared imaginaries act as coordination devices that yield ranked agendas and endogenous governance capacity. The resulting Maré Framework unwinds a portable chain: Uncertainty → Displacement → Cognitive Openness → Futures Exploration → Social Recommitment; and replaces vague “vulnerability”, making it empirically traceable. Policy implications include embedding community-ranked agendas in participatory budgeting and brokering cross-scalar alliances. This intervention also functioned as a structured research device. It demonstrates that a participatory futures laboratory can simultaneously generate community imagination and empirical insight into the social conditions of anticipation
Non-Aspergillus invasive mould infections in liver transplant recipients : a French national retrospective case-control study, 2007 to 2021
No full textInternational audienceBACKGROUND: Non-Aspergillus invasive mould infections (IMIs) are emerging in immunocompromised patients and liver is the second most commonly organ transplanted worldwide. METHODS: We conducted a multicenter retrospective case-control (1:1) study of liver transplant recipients diagnosed with non-Aspergillus IMIs in France between January 2007 and December 2021. RESULTS: We identified 27/14,332 (0.18%) LT recipients with non-Aspergillus IMIs. Mucorales spp. (48%) were the most common pathogens, followed by Scedosporium spp. (14%), Fusarium spp. (14%), and other IMIs (25%). Lungs were the primary infection site, followed by soft tissues, abdomen, brain, sinuses, heart, and bone. Multivariate analysis showed that a MELD score > 20 prior to transplantation and primary antifungal prophylaxis (with echinocandins or fluconazole) tended to increase the risk of non-Aspergillus IMIs by nearly threefold ((aOR: 3.73, 95% CI [0.90-15.45], p = 0.07) and (aOR: 3.93; 95% CI [0.94-16.42], p = 0.06) respectively). The 6-month mortality rate was 55%. In a Cox survival model, non-Aspergillus IMIs were associated with a threefold increase in mortality risk ((HR: 3.82 [2.01-7.26] p<0.001). CONCLUSION: Non-Aspergillus IMIs are rare but highly fatal infections whose early diagnosis in high-risk liver-transplanted patients is essential. Whether or not recently available molecular tools for diagnosing non-Aspergillus IMIs will improve their prognosis in the liver transplantation setting remains to be studied
Comparative investigation of numerical methods for incorporating real climate data into thermal quadrupole models for building wall applications: fitting techniques, and Laplace inversion algorithms
No full textInternational audienceThe thermal quadrupole method provides the advantage of expressing the partial differential formulation of the heat equation as a linear system in transformed time (Laplace transform) and space (integral transforms) domains. It allows faster computations compared to standard techniques such as Finite Element Methods. The following work concerns the incorporation of climate data recordings of hourly external temperature and solar heat flux in the thermal quadrupole method for solving the heat equation through a multilayered building wall.Two methods are proposed for the purpose of applying Laplace transforms to the discrete sets of climate data: a global Fourier series fit, accounting for severe fluctuations and peaks with the number of harmonics depending on dataset size; and a discrete Laplace transform methodology applied to a global series of linearly computed sub-series over defined intervals. Two models are investigated, a 1D heat transfer problem in Cartesian coordinates and a 2D axisymmetric representation in cylindrical coordinates, the latter dictating Hankel transforms for the space domain. After solving in the transformed domains, the challenge lies in accurately retrieving time-domain results. Three Laplace inversion algorithms—Stehfest, De Hoog, and Den Iseger—are investigated for their numerical stability, accuracy, and efficiency. A parametric analysis related to parameters of the data fitting and Laplace inversion methods is carried out. Results of different combinations of the fitting method/inversion algorithm (or a coupling of algorithms) are provided and compared with a finite element resolution of the thermal problems (FreeFEM++ and COMSOL) with an emphasis on computational time enhancements. The main objective of this work is to develop a numerically efficient direct model suitable for future application in inverse methods
Greedy window stochastic optimization algorithm for reducing data center energy consumption
No full textInternational audienceThis paper presents a stochastic model for Dynamic Power Management (DPM) in data centers-a strategy that involves dynamically activating and deactivating servers to balance energy efficiency with the maintenance of high Quality of Service (QoS). Unlike traditional methods that rely on predefined job arrival distributions, our approach leverages histograms to dynamically characterize job arrival patterns derived from real-world traces, empirical data, or live traffic measurements. We model the data center as a queuing system and introduce an efficient Greedy Window algorithm that is fast, memory-efficient, and capable of adapting to real-time fluctuations in job arrivals. This algorithm computes a suboptimal policy that closely approximates the optimal strategy attainable through stochastic combinatorial optimization techniques such as the Markov Decision Process (MDP). However, MDP-based approaches face challenges related to state space explosion and substantial computational demands in both time and memory. We evaluate our method across a range of data center configurations using real Google traffic traces and compare its performance against several optimization strategies
Modèles d'Ising de la Cooperativité dans la Contraction Musculaire
No full textInternational audienceRegulation of contraction in striated muscle is controlled by a dual mechanism involving both thin filaments containing actin and thick filaments containing myosin. The thin filament is activated by calcium ions binding to troponin, leading to tropomyosin azimuthal displacement which allows the activation of a regulatory unit (composed of one troponin, one tropomyosin and seven actin monomers) that exposes the actin sites for interaction with the myosin motors. Motor attachment to actin contributes to spreading activation within and beyond a regulatory unit along the thin filament through a cooperative mechanism. We introduce a one-dimensional Ising model to elucidate the mechanism of cooperativity in thin filament activation in relation to the force generated by the attached myosin motor. The model characterizes thin filament activation and cooperativity using only two parameters: one related to calcium concentration and the other to the force exerted by the attached myosin motor, which is modulated by temperature. At any force, the model is able to determine the extent of actin-myosin interactions on a correlation length ranging from two to seven actin monomers in addition to the seven actin monomers of the regulatory unit. Our theoretical predictions are successfully tested on experimental data, and our tests also include the condition of hindered filament activation by the use of the specific drug Omecamtiv Mecarbil (OM). According to our model, the effect of OM results in an anti-cooperativity mechanism accounting for the experimental data
