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D-ECS: Towards decentralising video games
No full textCurrent multiplayer video games are hard to scale in the number of players and simulated entities. Multiplayer architectures beyond basic client-server architectures are not provided by game engines and must be re-implemented for each game. Peer-to-peer approaches have been proposed to improve scalability, either to reduce the server network load created by broadcasts, or to create a scalable server infrastructure based on multiple machines. However, this approach increases the complexity of video game architectures. We provide a model to adapt games for p2p multiplayer, separating game and network logic. It allows for a game to be in a client-server or peer-to-peer setting seamlessly for any kind of game. We show how it can be applied to improve the performances and identify its security requirements and associated countermeasures
Evaluating the electronic structure and stability of epitaxially grown Sr-doped LaFeO 3 perovskite alkaline O 2 evolution model electrocatalysts
No full textInternational audienceIn this work, we have investigated the relationships between surface stability, electronic structure and O2 evolution reaction (OER) activity for epitaxial thin film La1−xSrxFeO3 (x = 0, 0.33, 0.8) model electrocatalysts before and after different electrochemical treatments. Cyclic voltammetry (CV) between +1.22 V and +1.92 V vs. RHE results in the continuous enhancement of OER performance of LaFeO3, while for La0.67Sr0.33FeO3 and La0.2Sr0.8FeO3 a gradual decrease of OER performance with increasing number of CV cycles was observed. A combination of atomic force microscopy, X-ray diffraction and X-ray reflectivity reveals that the surfaces of La1−xSrxFeO3 (x = 0, 0.33, 0.8) undergo surface morphology changes during OER treatment. Synchrotron ex situ X-ray photoemission spectroscopy data show a gradual down-shift of the Fermi level (EF) of LaFeO3 with increasing number of CV cycles, while near edge X-ray absorption fine structure spectroscopy (NEXAFS) at the Fe L-edge and O K-edge shows the presence of surface Fe4+ species as well as new hole states near the conduction band minimum upon electrochemical treatment, leading to a further enhancement of the electrochemical activity of LaFeO3. The newly formed hole state in LaFeO3 that appeared after 3 CV cycles remained constant upon progressing OER treatment. On the contrary, the decrease of OER performance of La0.67Sr0.33FeO3 and La0.2Sr0.8FeO3 with increasing CV cycles is attributed to an up-shift of EF along with a decrease of Fe4+ and hole state content after OER treatment. Furthermore, we found that the stability of the OER performance of La1−xSrxFeO3 is closely related to the leaching of Sr during OER, and the stability deteriorates with increasing Sr doping concentration in the pristine samples
Modélisation des pollutions diffuses d’origine agricole sur le bassin Seine-Normandie: Actualisation sur la période 2015-2023 de la base de données ARSEINE caractérisant les dynamiques des systèmes de cultureEvolution des systèmes de production agricoles de 2000 à 2020
No full textNeoadjuvant or perioperative therapy for melanoma metastasis in clinical practice: an international survey
No full textInternational audienc
Advancing beyond FEM: the Mixed Bodies Multi Shooting Method (MBMSM) for the modeling of static slender elements
No full textThis article introduces a novel approach termed "Mixed Bodies Multi Shooting Method" (MBMSM) for solving two-point boundary value problems in the statics of wires and beams, as an alternative to finite element methods (FEM). The MBMSM extends the classical multiple shooting method by incorporating static rigid bodies on which slender structures are connected through kinematic joints. This innovation enables efficient handling of geometric, material, and force discontinuities, as well as complex assemblies of slender bodies. Consequently, the MBMSM benefits from the accuracy and computational speed advantages of shooting methods. The method is developed for both 3D nonlinear kinematics of wires (deformation along the neutral axis only) and beams (Cosserat). In the case of beams, the method utilizes Modified Rodrigues Parameters (MRP) and their dual to parameterize rotations in large displacements, employing an MRP/SMRP switching algorithm to manage orientation singularities. Boundary conditions are reformulated in terms of kinematic and static constraints. An adaptive step integrator optimizes the number of integration points while maintaining accuracy. The MBMSM has been validated through numerous examples from the literature, demonstrating its accuracy and versatility for nonlinear static analysis of 3D slender structures.Cet article présente une nouvelle approche appelée « Mixed Bodies Multi Shooting Method » (MBMSM) pour résoudre les problèmes de valeur limite en deux bouts de la statique des fils et des poutres, en tant qu'alternative aux méthodes d'éléments finis (FEM). La MBMSM étend la méthode classique de tir simple et multiple en incorporant des corps rigides statiques sur lesquels des structures élancées sont connectées par des liaisons cinématiques. Cette innovation permet de traiter efficacement les discontinuités géométriques, matérielles et de force, ainsi que les assemblages complexes de corps élancés. Comparée aux méthode FEM, la MBMSM bénéficie des avantages inhérents aux méthodes de tir en termes de précision et de vitesse de calcul. La méthode est développée pour la cinématique non linéaire 3D des fils (déformation le long de l'axe neutre uniquement) et des poutres (Cosserat). Dans le cas des poutres, la méthode utilise les Modified Rodrigues Parameers (MRP) et leur dual (SMRP) pour paramétrer les rotations dans les grands déplacements. Les singularités d’orientation sont traitées par commutation entre MRP et SMRP. Les conditions aux limites sont reformulées en termes de contraintes cinématiques et statiques. Un intégrateur adaptatif optimise le nombre de points d'intégration tout en maintenant la précision. Le MBMSM a été validé par de nombreux exemples tirés de la littérature, démontrant sa précision et sa polyvalence pour l'analyse statique non linéaire de structures élancées en 3D
VeriFogOps: Automated Deployment Tool Selection and CI/CD Pipeline Generation for Verifying Fog Systems at Deployment Time
No full textInternational audienceFog Computing consists in decentralizing the Cloud by geographically distributing computation, storage, network resources, and related services. Among other benefits, it allows reducing bandwidth usage, limiting latency, or minimizing data transfers. However, Fog systems engineering remains challenging and quite often error-prone. Following best practices in software engineering, verification tasks can be performed before such systems are concretely deployed. Works already exist on verifying non-functional properties of Fog systems at different previous steps of the life cycle. This paper goes one step further and presents the VeriFogOps approach. This approach allows to automatically select deployment tools, based on expressed Quality of Service (QoS) requirements, and then generate relevant CI/CD pipelines supporting the deployment of Fog systems. We implemented and validated our approach via two realistic use cases, considering different QoS solutions and deployment tools. This work, developed in direct collaboration with our industrial partner Smile, goes towards the direction of a more comprehensive support for the entire life cycle of Fog systems, from design to actual deployment and execution
Mental practice improves pass accuracy in elite rugby players
No full textMental practice has been shown to improve motor performance; however, its effects in elite sports, particularly under constraints, remains underexplored. In this study, we examine the impact of mental practice, preceded by imagined or virtual game scenarios, on pass accuracy in elite rugby players. Seventy-five players from national and regional talent development teams participated in this study. They were divided into three groups: control (CTRL), motor imagery (MI), and virtual reality and motor imagery (VRMI) groups. All players completed pre- and post-tests assessing pass accuracy at three distances (10, 15 and 20 meters) under two conditions (with and without time constraints). Between the tests, the MI and VRMI groups performed three mental practice sessions over three different days. Each session consisted of two blocks of imagined (MI) or virtually observed (VRMI) stressful game scenarios (yellow card or try conceded) followed by imagined passes at each distance. The CTRL group did not engage in any practice during this period. Our results showed that mental practice improved pass accuracy under no constraints, with both MI and VRMI greater than CTRL (p<0.03 in all). Vividness of motor imagery improved over training sessions for MI and VRMI (p=0.01), but VRMI did not further enhance imagery vividness compared to MI alone. Under time constraints, pass accuracy at 20m declined during the pre-test for all groups (p=0.003). However, both mental practice groups failed to counteract this decrease at post-test. In conclusion, three mental practice sessions effectively enhanced pass accuracy under no constraints but did not mitigate the negative effects of time constraints on accuracy. Coaches and practitioners might consider implementing mental practice to further improve motor accuracy and reduce physical workload
Switching From Dupilumab to Tralokinumab or Janus Kinase Inhibitors in Cases of Ocular and/or Facial Adverse Events in Patients With Atopic Dermatitis: A Multicenter Retrospective Study
No full textInternational audienc
The atopic dermatitis patient journey: insights from a qualitative study
No full textInternational audienceThis qualitative study aimed to explore adults’ experiences with atopic dermatitis (AD) and gain insight into their expectations regarding healthcare, in order to improve their wellbeing. Data from 21 interviews were analysed. Participants reported a significant burden due to the psychosocial impact of AD, encompassing emotional distress and daily life impediments. Factors influencing treatment satisfaction among patients with AD extend beyond clinical efficacy. Dermatological care should consider patients’ preferences within treatment plans through a holistic approach to ensure satisfaction with their therapeutic regimen. We therefore encourage efforts to promote collaborative discussions between patients and physicians to improve treatment satisfaction
Spatial mapping of rheumatoid arthritis synovial niches reveals specific macrophage networks associated with response to therapy
No full textAbstract Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease affecting peripheral joints and for which approximately 40% of the patients respond insufficiently to the available synthetic or biologic disease modifying anti-rheumatic drugs (DMARDs). The infiltration of the synovial membrane by lymphocytes and monocytes profoundly alters its homeostatic functions, leading to chronic joint inflammation and bone destruction. A better understanding of how DMARDs impact the complex synovial cell social network in relationship to response/ non-response remains an unmet need to design more targeted and active therapeutic strategies. Here, we used imaging mass cytometry (IMC) to comparatively profile more than 115,000 cells in the synovial tissue of healthy, low inflammatory osteoarthritis and matched active early treatment-naïve RA patients at baseline and at 6 months after starting DMARDs treatment. We notably highlighted that tissue resident macrophages (LYVE1 + CD206 + ) in perivascular synovial niches encompassing specific subsets of vascular cells, fibroblasts and immune cells vanished in active RA but were recovered in response to DMARDs treatment. Combined ligand-receptor analysis of single-cell RNA sequencing datasets identified that IL10, C-type lectin or TAM (TYRO3, AXL and MERTK) receptors were particularly involved in the restoration of these spatial cell interactions in the context of clinical remission. In addition to providing an unprecedented synovial spatial mapping, our work uncovered novel potential cellular and molecular targets for the development of therapies for RA. One Sentence Summary Single-cell spatial profiling of rheumatoid arthritis synovium identifies specific cell states linked to treatment respons