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Impact des traitements psychotropes sur la qualité du sommeil : analyse critique des effets iatrogènes des antidépresseurs, anxiolytiques et hypnotiques.
No full textLes troubles du sommeil représentent un enjeu majeur de santé publique et sont fréquemment associés aux troubles anxieux et dépressifs. Les traitements psychotropes — antidépresseurs, anxiolytiques et hypnotiques — sont largement prescrits pour améliorer le sommeil. Toutefois, de nombreuses données suggèrent que ces médicaments peuvent altérer l’architecture physiologique du sommeil, induire une tolérance, favoriser une dépendance fonctionnelle et contribuer à une chronicisation des troubles.Ce travail vise à analyser de manière critique l’impact réel des traitements psychotropes sur la qualité du sommeil et à évaluer l’évolution des paramètres cliniques et objectifs du sommeil lors d’un sevrage progressif encadré, associé à une prise en charge non pharmacologique.Il s’agit d’une étude observationnelle prospective menée entre janvier 2026 et janvier 2027 auprès de 107 patients suivis pour troubles du sommeil et traités par psychotropes. Les participants bénéficieront d’un sevrage progressif individualisé, associé à des interventions non pharmacologiques. L’évaluation reposera sur des échelles validées (ISI, PSQI, Epworth, HADS), des examens de polysomnographie, des données de pharmacovigilance et un suivi clinique détaillé.Nous faisons l’hypothèse qu’à moyen et long terme, la réduction ou l’arrêt encadré des psychotropes, associé à des stratégies non médicamenteuses, permet une amélioration de la qualité du sommeil malgré un possible rebond transitoire initial.Intérêt. Cette étude vise à mieux comprendre la discordance entre amélioration subjective et altération objective du sommeil sous psychotropes, et à proposer un modèle pharmaco-clinique rationnel de déprescription et de prise en charge globale des troubles du sommeil
Analyse Structurelle des changements de mode dans les DAE multimodes
No full textHybrid systems are an important concept in Cyber-Physical Systems modeling, for which multiphysics modeling from first principles and the reuse of models from libraries are key. To achieve this, DAEs must be used to specify the dynamics in each discrete state (or mode in our context). This led to the development of DAE-based equational languages supporting multiple modes, of which Modelica is a popular standard. Mode switching can be time-or state-based. Impulsive behaviors can occur at mode changes. While mode changes are well understood in particular physics (e.g., contact mechanics), this is not the case in physics-agnostic paradigms such as Modelica. This situation causes difficulties for the compilation of programs, often requiring users to manually "smooth out" mode changes. In this paper, we propose a novel approach for the hot restart at mode changes in such paradigms. We propose a mathematical meaning for hot restarts (such a mathematical meaning does not exist in general), as well as a combined structural-and-impulse analysis for mode changes, generating the hot restart even in the presence of impulses. Our algorithm detects at compile time if the mode change is insufficiently specified, in which case it returns diagnostics information to the user.La modélisation des systèmes cyber-physiques repose sur une modélisation à partir des principes de la physique, et en réutilisant au maximum des modèles prédéfinis issus d’unebibliothèque. Cela exige le recours aux Equations Différentielles Algébriques (DAE) admettant plusieurs modes (une DAE commutée, ou une DAE hybride). Le standard de modélisation est le langage Modelica. Les changements de mode peuvent ˆetre déclenchés de manière externe, ou par des conditions portant sur les états. Ces changements de mode sont connus et traités à l’intérieur de physiques particulières (mécanique avec contacts). Il en va autrement dans un cadre multi-physique général, qui est, pourtant, celui de Modelica et d’autres langages de modélisation multi-physique. Dans ce papier, nous proposons une approche nouvelle pour le redémarrage à chaud suite à un changement de mode. Noter qu’il n’existe pas de définition mathématique de ce qu’est une solution dans notre cadre général. Notre méthode utilise une analyse structurelle doublée d’un calcul symbolique des comportements impulsifs. Notre méthode s’applique lors de la phase de compilation et permet de détecter, avant toute simulation, si le modèle soumis est éventuellement insuffisamment spécifié
Characteristics of ovarian stimulation in adolescents and young adults undergoing fertility preservation
No full textInternational audiencePurpose: To compare the ovarian response to controlled ovarian hyperstimulation (COH) performed for fertility preservation (FP) in adolescents and young adults (AYA) aged ≤20 years with that of adult women aged 25-35 years.Materials and methods: This retrospective cohort study included 66 COH cycles in AYA patients (≤20 years) and 107 cycles in adults (25-35 years) treated between January 2014 and March 2022 for oocyte vitrification. Outcomes assessed included the number of mature oocytes vitrified, total oocytes retrieved, total rFSH dose, peak estradiol levels, maturation rate, and duration of stimulation.Results: Groups were comparable regarding BMI, smoking status, AMH, stimulation protocol, and gonadotropin type. Median number of mature oocytes was not statistically different between groups: (9.5 (AYA) vs. 9.0 (A), p = 80.19). The maturation index was significantly lower in AYA (0.80 vs. 0.88, p = 80.02). Peak estradiol was lower in AYA (1267 pg/mL vs. 1582 pg/mL, p = 80.04). Other stimulation parameters were similar.Conclusion: Fertility preservation through COH in adolescents and young adults appears as effective as in adult women in terms of mature oocyte yield. Nevertheless, AYA patients exhibit a lower oocyte maturation rate and lower peak estradiol levels. Larger studies are needed to confirm these findings and better characterise age-related physiological differences in ovarian response
Internal tide loss of coherence in a realistic simulation of the North Atlantic
No full textInternational audienceAbstract. The loss of coherence of the semidiurnal internal tide is investigated using a high-resolution realistic numerical simulation over the North Atlantic. The analysis focuses on processes resulting from the interaction between the internal tide and the mesoscale background flow at time scales typically shorter than one month. To this end, a theoretical framework based on vertical mode decomposition and the splitting of the internal tide signal into coherent and incoherent components is developed and applied to the outputs of the numerical simulation. This framework enables the transfer terms between the coherent and incoherent parts, and between the different vertical modes – and therefore horizontal scales – of the internal tides to be evaluated. By focusing on three subdomains with contrasting dynamics, we demonstrate that coherent-to-incoherent energy transfers significantly impact the internal tide energy budget. These transfers are dominated by advection by slowly varying flows and mainly occur without changing the vertical mode of the internal tide involved. This is attributed to the dominance of the barotropic and first baroclinic modes in the mesoscale flow combined with the structure of the mesoscale flow/internal tide interaction terms. Typical energy transfer rates are of the order of a few tens of days in the Gulf Stream region and a few hundred days in the Azores for the mode 1 internal tide
Cross-sectional evaluation of exposure to ozone, nitrogen dioxide, and particulate mass levels on circulating immune markers in women in the California Teachers Study
No full textInternational audienceAbstract Exposure to ambient air pollutants, specifically ozone (O 3 ), nitrogen dioxide (NO 2 ), ultrafine, fine or coarse particulate matter (PM 0.1 , PM 2.5 , and PM 10 ), has been linked to a number of adverse health outcomes, including cardiovascular disease. Changes in immune response may be a key mechanism underlying these effects. Within the California Teachers Study cohort, we conducted a cross-sectional analysis of 1,898 women to assess the associations between exposure to O 3 , NO 2 , PM 0.1 , PM 2.5 , and PM 10 and 15 immune markers measured from serum samples collected in 2015. Daily residential exposures to O 3 , NO 2 , PM 0.1 , PM 2.5 , and PM 10 were estimated by a validated chemical transport model and averaged over 12-, 3-, and 1-month periods prior to blood draw. Fifteen immune markers (categorized as quartiles) were estimated per interquartile range (IQR) of air pollutant exposures using multivariable ordinal logistic regressions adjusted for age, body mass index, and respective pollutants. Immune markers were also grouped into immune pathways (pro-inflammatory/macrophage activation, B-cell activation, and T-cell activation). After applying Bonferroni correction, elevated exposure to O 3 levels at all three exposure windows were associated with elevated circulating levels of IL-1β (interleukin-1 beta), IL-8 (interleukin 8), sTNFR2 (soluble tumor necrosis factor receptor 2), and sgp130 (soluble glycoprotein 130). Elevated O 3 at 3- and 1-month periods were associated with increased levels of sCD27 (soluble cluster of differentiation 27) and BAFF (B-cell activating factor). In pathway analyses, O 3 was consistently and significantly associated with the pro-inflammatory/macrophage activation pathway (12-month OR = 1.49, 3-month OR = 1.57, 1-month OR = 1.54) and with B-cell activation at all three exposure windows (12-month OR = 1.24, 3-month OR = 1.53, 1-month OR = 1.41). NO 2 was positively associated with TNFα at the 3- and 1-month exposure windows. For the PM size fractions, sporadic, mainly inverse, associations with immune markers were observed. Elevated O 3 exposure up to one year prior to blood draw was associated with elevated immune markers related to pro-inflammatory response, macrophage activation, and B cell activation. These findings suggest potential immunologic pathways linking air pollution to adverse health outcomes in women
Fast Estimation of mmWave Power-Angular Spectrum Using Leaky-Wave Antennas
No full textInternational audienceLeaky-wave antennas (LWAs) provide compact andcost-effective solutions for direction-of-arrival (DoA) estimationdue to their frequency-dependent beam-scanning characteristics.However, in coherent multipath environments, the source covariancematrix becomes rank-deficient, which limits the performanceof conventional subspace-based methods. Interpolationbasedspatial smoothing (SSP) can restore the rank and recoverDoAs, but accurate power estimation remains difficult, hinderingthe acquisition of the power angular spectrum (PAS). In thiswork, we propose an on-grid sparse Bayesian learning (SBL)approach that operates directly on the fast frequency-scanningresponses of meandered waveguide-based LWAs. The methodjointly estimates DoAs and their corresponding powers withoutrequiring rank-restoration techniques. Simulation results demonstratethat the SBL-based approach provides robust and accuratePAS estimation, even in the presence of fully coherent sources
A Hybrid Message-level Modeling Approach for Fast Yet Accurate Simulation of Multiprocessor Shared Bus Effects on Data Flow Applications Execution
No full textInternational audienceFast yet accurate performance and timing prediction of complex parallel data flow applications on multiprocessor systems remains a challenging discipline. The main reason is that the applications contain numerous degrees of parallelism (task, pipeline, data) but they necessitate sharing resources, such as communication buses and memories, within execution platforms. Executing such applications on resource-limited platforms leads to timing interferences that are difficult to accurately express in pure analytical approaches or to excessive simulation duration for cycle-accurate models. In this work, we propose a message-level communication model for fast yet accurate performance prediction for data flow applications executed on MPSoCs with shared memories and buses. This approach combines a high level executable model of the communication infrastructure with a formal description of the synchronization instants related to low-level communication mechanisms. This combination significantly reduces the number of simulation events while still accurately predicting the effects of contention at shared resources. We evaluated our work against measurements from a real prototype and cycle-accurate performance prediction models on two case-studies from the computer vision domain. We illustrated how the computational complexity of our approach can be adapted to deliver high simulation efficiency. In our experiment, we achieved an average accuracy of 99% in latency prediction compared to real implementation for the different use-cases and mappings we considered. In the experiments where the approach is used with limited computational complexity, simulation speed-ups of an order of magnitude of 104 compared to cycle-accurate models are achieved, while maintaining a fully acceptable accuracy (more than 98%). Good suitability for fast and accurate exploration of the design space is demonstrated by the proposed models
Automatic Extraction of Timing Models for WCET Estimation From a High-Level Synthesis Flow
No full textInternational audienceReal-time, domain-specific processors require faithful timing models for WCET analysis. However, existing models are typically hand-crafted from sparse documentation, making them error-prone and difficult to maintain. This work aims to automatically extract WCET timing models from single-issue in-order processor pipelines generated by High-Level Synthesis (HLS). By deriving timing models directly from the SpecHLS intermediate representation, the models are faithful by construction. Experimental results show that our timing-model extraction process generalizes across diverse RISC-V core variants and yields WCET estimates within 0.48% on average of those from a handcrafted model, on the Mälardalen WCET benchmarks
Hybodont shark remains from Campanian (Upper Cretaceous) continental deposits of southern France
No full textInternational audienceThe hybodont shark (Elasmobranchii, Hybodontiformes) material from the Campanian of two non-marine localities in southern France are described. Some teeth and a dorsal fin spine from the upper Campanian of Velaux are assigned to the genus Meristodonoides (Hybodontidae), whereas a single tooth from the lower Campanian of Villeveyrac is referred to Parvodus (Lonchidiidae), a genus hitherto unknown in the Upper Cretaceous. Among the latest Cretaceous continental ichthyofaunas of the European archipelago, hybodont sharks may have been minor relictual components with spatially restricted distributions, as suggested by their scarcity in the fossil assemblages from France and Romania combined with their apparent absence in other areas (Iberian Peninsula, Hungary)