Portail HAL de l'Université Picardie Jules Verne
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La politisation du vécu handicapé. Ressources et contraintes de la mobilisation antivalidiste en France
No full textInternational audienceBy analyzing anti-ableist collectives in France, this article explores the emergence of a mobilisation based on the "politicization of experience" of its members. It has come up against a number of obstacles, linked to the characteristics of the disabled population and the history of the disability movement. However, over the last ten years, disabled activists have been de-individualising their experiences and placing them within a systemic framework. This has led to the creation of organisations whose claims are part of a new definition of the public problem of disability, competing with the historically dominant definition. The recurring expression of fatigue among anti-ableist activists shows that these obstacles remain, explaining the instability of this mobilisation and the recurring disengagement of its members, despite their attachment to the cause.En analysant les collectifs antivalidistes en France, cet article explore l’émergence d’une mobilisation basée sur la « politisation du vécu » de ses membres. Elle s’est heurtée à plusieurs contraintes liées aux caractéristiques de la population handicapée et à l’histoire de l’espace de la cause du handicap. Cependant, depuis une dizaine d’années, des militants handicapés désingularisent leurs expériences et les inscrivent dans un cadre systémique. Cela a permis la création de collectifs dont les revendications s’inscrivent dans une nouvelle définition du problème public du handicap, concurrençant la définition historiquement dominante. L’expression récurrente de la fatigue des antivalidistes atteste du maintien de ses contraintes, qui participent de l’instabilité de cette mobilisation et de la récurrence du désengagement de ses membres, malgré leur attachement à la cause
Additive manufacturing by binder jetting of thick electrode for Li-ion battery
No full textInternational audienceBinder jetting (BJ) has drawn attention to its ability to quickly produce complex objects using minimal amount of additives, being suitable for ceramic materials with high porosity. Thanks to these advantages, this additive manufacturing (AM) technique is now of interest in the field of energy storage.A successful NMC622 (LiNi0.6Mn0.2Co0.2O2) thick electrode was fabricated using an aqueous formulation showing a final porosity of 35%. When cycled in half cell configuration versus lithium metal between 4.3 and 3 V at 0.2 mA/cm2, the printed electrode delivers a reversible capacity of 155.2 mAh/g after 10 cycles. These results, presented as a proof of concept, establish Binder Jetting as a possible route to manufacture thick and self-supported electrodes with an areal capacity of 8.33 mAh/cm2 at 0.2 mA/cm2
Integral-Type Terminal Sliding Mode MPPT Controller for a Standalone PV System With a DC–DC Boost Converter Under Real-Time Varying Weather Conditions
No full textInternational audienceRobust nonlinear controllers, in particular sliding mode control (SMC), have been a convenient solution for maximum power point tracking (MPPT) of photovoltaic (PV) systems, as they deal with the nonlinearity of the system and can catch the MPP in various weather conditions; however, chattering and infinite time of convergence have been related to conventional sliding mode control. In this article, we propose an integral-type terminal sliding mode MPPT (ITTSMC) controller for a PV system powering a DC load, based on the tracking error of the inductor's current of the DC-DC boost converter, which is connected to the PV array's output, to follow the MPP. The paper provides a theoretical study of the controller in question, demonstrating its stability and its finite-time convergence. The controller is tested under four environmental conditions, firstly, standard test conditions with a constant load, then with a variable load, secondly, a step changes in temperature and irradiance, thirdly, under real weather conditions relying on the data of temperature and irradiance of a weather station in the Faculty of Sciences and Technologies of Errachidia in the eastern south of Morocco, finally, the controller will be evaluated under realistic partial shading conditions. To assess its performance, the ITTSMC is compared to the basic terminal SMC and the classical SMC. The ITTSMC achieves an 85% reduction in reaching time, a reduction of up to 88% in chattering magnitude, and a 66% decrease in voltage RMSE compared to SMC. Moreover, it exhibits strong robustness under real environmental conditions and partial shading while ensuring high-precision MPP tracking. Overall, the ITTSMC reaches a power extraction efficiency of 99.92%, outperforming TSMC (99.81%) and classical SMC (99.64%). These quantitative improvements clearly demonstrate the superior tracking accuracy, faster transient response, and reduced chattering of the proposed control strategy
Cross‐Continental Ecological Drivers Behind Trait Clines in the Forest Grass Milium effusum
No full textInternational audienceAim Widespread species encounter a range of variable climates that can lead to intraspecific trait clines. Such clines can be the result of phenotypic plasticity, genetic differences, or both. Although latitude often explains a large part of trait variation, it is crucial to investigate the underlying environmental variables to understand current and future trait responses. Cross‐continental comparisons of species that are native on multiple continents provide a rarely used approach that can help identify the environmental drivers of intraspecific trait clines. Location Europe and North America. Time Period 2021–2023. Major Taxa Studied Milium effusum L. (Poaceae). Methods To quantify the influence of environmental gradients on functional traits across geographical regions that vary in climate, we sampled M. effusum seeds from 23 European and 14 North American populations and transplanted them in a common garden. We measured 10 vegetative, reproductive, and phenological traits. We used 30‐year averages of 19 bioclimatic variables, while accounting for the latitudinal and elevational position of the population origins, to compare the trait‐environment relationships between continents. Results Our results showed that European populations occupy a broader climatic range than North American populations. Differences between continents were found in most of the traits as well as in the multivariate trait space. The traits were affected more by bioclimatic variables than by latitude or elevation. While flowering, leaf thickness, specific leaf area, and reproductive height showed parallel clines to the environment between continents, vegetative height and biomass showed contrasting clines. Main Conclusions Environmental influences from population origins revealed parallel clines between the continents for functional traits, suggesting shared selective pressures, while contrasting clines for plant size indicated different evolutionary trajectories, potential bottlenecks, or interactions with unknown ecological factors. This study highlights the complex interplay of genetic, environmental, and evolutionary factors in shaping phenotypic variation in native species across continents
Cardiovascular Magnetic Resonance Late Gadolinium Enhancement Risk Score for Mortality in Patients with Hypertrophic Cardiomyopathy: the HCM-LGE Risk Score
No full textInternational audienceBackground: The concept of “late gadolinium enhancement (LGE) granularity” using cardiovascular magnetic resonance (CMR) has been described as a strong prognosticator for patients with cardiomyopathy.(1, 2) No score has been developed using LGE in patients with hypertrophic cardiomyopathy (HCM) for clinical routine.The aim of the study was to develop and validate a score using the “LGE granularity” concept to predict mortality in HCM patients.Methods: The study cohort was based on the multicentric HCM-LGE registry, that included 2,873 patients with HCM referred for CMR between 2008 and 2021 in three French centers. The HCM-LGE risk score was developed using multivariable Cox coefficients of the “LGE granularity” concept from the training cohort (N=1,609). Then, this score was evaluated by time-dependent AUCs, precision recall curves, and calibration at 5 years on testing (N=199) and external validation (N=272). The primary outcome was all-cause mortality using the French National Death Registry. Based on the HCM-LGE risk score, patients were classified into 3 risk groups: low-risk (≤3 points), intermediate-risk ( >3 and ≤5 points), and high-risk ( >5 points). Survival probabilities were estimated using the Kaplan-Meier method and compared with the log-rank test.Results: The HCM-LGE risk score showed good performance in time-dependent analysis, with AUC of 0.72 (95% CI: 0.65, 0.79) and precision-recall AUC of 0.52 (95% CI: 0.48-0.56) in the external validation cohort. Cox analysis showed escalating risk from intermediate-risk (aHR: 2.61, [95% CI: 1.33-5.15]) to high-risk patients (aHR: 3.50, [95% CI: 1.90-6.45]; both p< 0.001). The HCM-LGE risk score showed the best improvement in model discrimination and reclassification above traditional prognosticators (Harrell’s C-statistic improvement: 0.09; NRI=50%; IDI=17%, all p< 0.001).Conclusion: The HCM-LGE risk score is a straightforward and reliable mortality risk prediction score for patients with HCM using readily available LGE parameters, with an incremental prognostic value above traditional prognosticators
Picasso au musée de Chypre. Œuvres en céramique : catalogue d'exposition, musée archéologique de Chypre, 2019
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International Magnetic Resonance Imaging Consensus for use in Luminal Crohn’s Disease Trials and Clinical Practice
No full textInternational audienceBackground and aimsCross sectional imaging is an integral part of evaluating disease activity and complications in Crohn’s disease. There remains a need to develop guidance that may be for both clinical trials and clinical practice. This initiative aimed to develop consensus statements for definitions of response and remission, transmural healing, optimal timing for assessing, and evaluation of treatment efficacy in patients with Crohn’s disease using magnetic resonance enterography (MRE) in clinical trials and clinical practice.MethodsThirty-three international experts (gastroenterologists (n=29) and radiologists (n=4) participated in a consensus process. A systematic literature review was conducted to inform initial consensus, statements were discussed and voted using a modified Delphi method. Consensus was defined as at least 75% agreement among voters.ResultsThe MaRIA score and the simplified MaRIA score should be used to determine response and remission in moderate to severe Crohn’s disease. Response was defined as a MaRIA score <11 or an improvement of at least 25%, and a decrease of at least 1 point in the simplified MaRIA score. Remission was defined as a MaRIA score <7 or a simplified MaRIA score <1. Five different definitions were proposed for transmural healing. For the time point of assessment, the group proposed week 24 for response, weeks 24, 52 or 54 for remission, and weeks 52 or 104 for transmural healing.ConclusionA consensus expert panel has developed standardized definitions of MRE response, remission, as well as the optimal timing for response assessment in patients with luminal Crohn’s disease. Further research is needed to clarify the method for measuring transmural healing
Passing the right colic angle can also lead to complications in coloscopy
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The Weaning Index during Spontaneous Breathing Trials for Predicting Extubation Failure in Critically Ill Patients: A Bicentric Prospective Study
No full textInternational audienceBackground: An increase in the Weaning Index (WI), defined as the product of end-tidal carbon dioxide (EtCO2) and respiratory rate (RR), has been observed in patients who fail spontaneous breathing trials (SBT). This study aimed to assess whether the WI recorded during SBT can predict extubation failure (EF) in critically ill patients.Methods: In this bicentric prospective study, ICU patients mechanically ventilated for at least 48 hours and who successfully tolerated a 30-minute SBT were included. EtCO2, RR, and WI were recorded at the beginning and end of the SBT. Changes in these parameters were analysed. Predictive performance for EF on day 7 was assessed, including areas under the receiver operating characteristic curves (AUCs).Results: Among the 114 patients, 23 (20.2%) experienced EF. Absolute changes (median [IQR]) of EtCO2, RR and WI were higher in failure group than success group respectively: 1.0 [-1.0-3.4] mmHg, 3 [1-5] breaths/min and 169.0 [94.0-232.0] mmHg x breaths/min versus -0.2 [-0.2-1.0] mmHg (p = 0.003), 0 [-1-1] breaths/min (p < 0.001) and -6.0 [-59.0-38.0] mmHg x breaths/min (p < 0.001). In multivariate adjusted models, increases in EtCO2, RR, and WI were independently associated with EF, respectives OR [95% CI]: 1.78 [1.30-2.44], 3.26 [1.77-6.01], and 1.03 [1.01-1.04]. ΔEtCO2 showed limited predictive ability for EF (AUC = 0.70 [95%CI: 0.61-0.78]), whereas ΔRR and ΔWI demonstrated excellent discrimination (AUC = 0.84 [95%CI: 0.76-0.90] and AUC = 0.91 [95%CI: 0.85-0.96]).Conclusions: SBT-induced changes in RR and WI demonstrated excellent performance in predicting EF in critically ill patients. In contrast, changes in EtCO2 during the SBT provided limited predictive value.Registration: The study was registered in the ClinicalTrials.gov registry: NCT05802745
Impact of dual-axis elevated photovoltaic systems on bats’ activity and foraging behavior in wheat fields and hay meadows
No full textInternational audienceDespite rapid agrivoltaic (APV) development, little is known about their effects on bats. We assessed dual-axis elevated photovoltaic systems’ impact on bat activity in 17 agricultural plots (10 wheat fields, 7 hay meadows) in western France (2023–2024). Acoustic surveys were conducted at three standardized plot locations (near photovoltaic system (PV), center of the field, hedge) using ultrasonic recorders. Bat activity was quantified at the guild level and by species within guilds. Feeding buzzes from orientation calls helped identify foraging activity, while insect density on sticky traps and plant species richness served as indirect prey availability proxies. We tested the effect of recorder location on bat activity, feeding buzzes, arthropod biomass, plant species richness and their interrelations using generalized linear mixed models. In wheat fields, mid-range echolocators showed significantly higher activity and more feeding buzzes near PV system than in plot center but it was not correlated with higher arthropod biomass, suggesting bats were not attracted by prey density. Generalist species like Pipistrellus pipistrellus and P. kuhlii may be attracted by the PV’s structure as an isolated vertical element potentially acting as a landmark. Short-range echolocators as Barbastella barbastellus and Rhinolophus spp., preferred hedgerows, likely due to their reliance on structurally complex habitats and aversion to open areas. Long-range echolocators, which forage at higher altitudes, showed little response to PV structures, consistent with their independence from ground-level features. Agrivoltaic structures can thus locally influence bat behavior, creating microhabitats benefiting adaptable species. Clarifying interactions across APV systems is vital for designing solar installations that integrate ecological considerations