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Dry electrode architecture design to push energy density limits at the cell level
No full textInternational audienceHigh-energy lithium batteries require electrode architectures that enable high areal capacity, high active material content, and stable high-voltage operation—requirements that conventional slurry-based electrodes struggle to meet due to inefficient electron percolation, parasitic reactions, and limited processing-architecture predictability. Here we design and validate a dry-processed electrode architecture that leverages molecular-level coupling between fibrous carbon and binder to promote efficient electronic conduction while suppressing high-voltage interfacial degradation. This architecture achieves areal loadings >5 mAh cm−2 with >99 wt% active material and supports stable operation up to 4.70 V without compromising rate capability. The 4.55 V NMC811||graphite pouch cells retain 78% capacity after 1,000 cycles at C/3-rate, with average Coulombic efficiency exceeding 99.9%. These results are achieved without material-level modifications or specialized electrolyte additives, highlighting the potential of electrode engineering alone to unlock the intrinsic performance of active materials even under demanding conditions of high areal loading and maximum active material content
Comment on "Skin grafting as a preventive strategy against infections in children with deep burns."
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Le processus d’intention d’achat en ligne à l'ère du live streaming commerce : rôle central de l’expérience de flow
No full textInternational audienceCette recherche propose un modèle intégré expliquant comment la confiance du consommateur et l'expérience de flow s’articulent de manière complémentaire dans le processus d’intention d’achat lors du live streaming commerce (LSC). Ce modèle, fondé sur les théories de l’échange social et du flow, introduit deux routes principales : la route cognitive établit le lien entre les caractéristiques du streamer et la confiance envers le produit et la route affective associe les caractéristiques du LSC à l’expérience de flow. Une troisième route qualifiée de mixte représente la relation entre la confiance et l’expérience de flow. Cette route mixte illustre les mécanismes séquentiels conduisant à l’intention d’achat en ligne. Dans un premier temps, une étude qualitative a permis de consolider la pertinence des concepts intégrés dans le modèle de recherche. Par la suite, une étude quantitative réalisée en France auprès de 555 répondants a permis de tester le modèle proposé. Les résultats révèlent la médiation totale de la confiance concernant l’effet des caractéristiques du streamer sur l’intention d’achat. Ils montrent également la médiation totale de l’expérience de flow. La confiance représente ainsi une base cognitive nécessaire mais insuffisante pour accroître l’intention d’achat en ligne. Ce n’est que par son effet médiatisé via l’expérience de flow que cette intention s’intensifie. La mise en évidence de l’articulation entre la confiance (cognition) et le flow (affect) éclaire les mécanismes sous-jacents à l’intention d’achat en ligne et ouvre de nouvelles perspectives de recherche
Chlorhexidine vs Povidone-Iodine Alcohol Solutions for Cardiac Implantable Electronic Devices
No full textInternational audienceBACKGROUND Cardiac resynchronization therapy (CRT) improves heart failure outcomes and reduces morbidity and mortality but carries the highest infection risk among cardiac implantable electronic devices. Studies on surgical-site infections show conflicting results regarding the use of alcohol-based povidone-iodine vs chlorhexidine for skin antisepsis, especially as CRT implantation remains insufficiently studied. OBJECTIVES This study sought to compare the effectiveness of 2% alcohol-based chlorhexidine with that of 4-phase povidone-iodine-alcohol skin preparation in preventing local or systemic infections after cardiac resynchronization therapy device implantation, and to assess the impact on other major cardiovascular events and treatment-related adverse effects over 24 months. METHODS In this randomized, multicenter, open-label trial with blinded outcome adjudication, patients undergoing CRT (implantation, upgrade, or replacement) pacemaker, or defibrillator implantation were assigned 1:1 to receive skin antisepsis with either 2% alcoholic chlorhexidine or alcoholic povidone-iodine. Randomization was conducted centrally using an interactive web-response system, with stratification according to trial center. The primary outcome was local or systemic infection related to the device over a 24-month follow-up period. The secondary outcomes were major cardiovascular events and noninfectious side effects. RESULTS From April 2013 to December 2018, 2,272 patients were randomized to the chlorhexidine (n = 1,143) or the povidone-iodine group (n = 1,129). Median age was 72 years; 75.1% were men. Device-related infections occurred in 2.9% of the chlorhexidine group and 3.9% of the povidone-iodine group (adjusted subhazard ratio: 0.75; 95% CI: 0.48-1.20; P = 0.23). Major cardiovascular events occurred in 31.5% and 31.3% of patients, respectively (subhazard ratio: 1.01; 95% CI: 0.87-1.17). Noninfectious local side effects occurred in 12.9% vs 13.3%. CONCLUSIONS The study did not demonstrate a significant reduction in infection rates with alcoholic chlorhexidine compared with alcoholic povidone-iodine in patients undergoing cardiac resynchronization device implantation. Both antiseptics showed similar rates of major infectious and noninfectious events. Further research is needed to optimize infection prevention strategies in this population. (Comparison of Alcoholic Chlorhexidine 2% Versus Alcoholic Povidone Iodine for Infections Prevention With Cardiac Resynchronization Therapy Device Implantation [CHLOVIS]; NCT01841242) (JACC. 2026;87:200-211) (c) 2026 by the American College of Cardiology Foundation
Phytochemical and pharmacological elucidation of Jasonia glutinosa (L.) fourr. essential oil: a promising therapeutic source against inflammation and cancer
No full textInternational audienceThe growing demand for natural therapeutics with safer pharmacological profiles has renewed interest in aromatic plants traditionally used in folk medicine. Jasonia glutinosa (L.) Fourr. (Asteraceae), commonly known as "sticky fleabane", is a medicinal and aromatic species widely employed for its digestive and anti-inflammatory benefits. Despite its ethnopharmacological relevance, the bioactive potential of its essential oil remains poorly explored. This study provides a multifaceted investigation of the chemical composition, safety profile, and pharmacological activities of J. glutinosa essential oil (JGEO). Gas chromatography-mass spectrometry (GC-MS) analysis revealed nerolidol (51.29%) as the predominant constituent, accompanied by isoaromadendrene epoxide (17.39%) and cis-α-copaene-8-ol (9.92%). The genotoxicity assessment, conducted using the alkaline comet assay on rat leukocytes, demonstrated no significant DNA damage at concentrations up to 100 µg/mL, confirming the oil's genomic safety within the tested range. Pharmacological evaluation showed that JGEO exerted potent anti-inflammatory effects, significantly reducing nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in LPS-stimulated macrophages - with NO levels decreasing to 18.4% of control values and PGE₂ from 720 µM to 108.2 µM (p < 0.001). Moreover, JGEO exhibited selective cytotoxicity against multiple human cancer cell lines, with IC₅₀ values of 15.43 µg/mL (MCF-7), 24.24 µg/mL (MDA-MB-468), 74.57 µg/mL (HCT-15), and 18.06 µg/mL (HepG2). Remarkably, high selectivity indices for MCF-7 (SI = 63.67) and HepG2 (SI = 54.40) surpassed those of doxorubicin, highlighting its favorable therapeutic window. Collectively, these findings provide a scientific basis for the traditional uses of J. glutinosa, emphasizing its safety, efficacy, and chemical richness. The study positions JGEO as a promising natural source of bioactive terpenoids for the development of anti-inflammatory and anticancer agents, supporting its further exploration in pharmaceutical and nutraceutical formulations
Impact of Environmental Exposure on Infant Sleep : The Exposome Approach
No full textInternational audienceSleep is fundamental for infant development and health, playing a critical role in cognitive, socio‐emotional, and physical growth. However, environmental factors can impact the quality and duration of sleep in infants. This review synthesises current evidence on the associations between environmental chemical exposures and infant sleep outcomes, with a focus on the first 1000 days of life. Infants may be exposed to environmental pollutants before birth, through the placenta, or after birth, via breastfeeding, diet, and external sources such as inhalation, dust contact, or hand‐to‐mouth exposure. Given their ongoing development, foetuses and infants are particularly vulnerable to these pollutants. This period of rapid growth and maturation represents a highly sensitive window for environmental exposures. This review covers various categories of environmental pollutants, including persistent organic pollutants (PCBs, dioxins), non‐persistent pollutants (phthalates, BPA), air pollutants (particulate matter, second‐hand smoke), and water contaminants (nitrates, microplastics). Environmental chemicals exposure could be assessed using parental questionnaires or biological monitoring, while sleep is evaluated using actigraphy, polysomnography, or parental reporting. Some evidence suggests that both prenatal and postnatal exposure to environmental contaminants may be associated with sleep disturbances in children, particularly in girls. Despite the numerous studies on adults and the mechanisms associated with these pollutants (neurotoxicity, endocrine disruption), which suggest an effect on sleep, there is a lack of studies in children, resulting in limited associations in the literature. Therefore, it is imperative to conduct studies on environmental pollutants present in breast milk, diet, and/or ambient air to understand their impact on infant sleep
Rational and design of EACVI-MMVD study: an international registry on multimodality imaging for mixed and multiple valvular heart disease
No full textInternational audienceAims Multiple and mixed valvular heart disease (MMVD) are frequent situations in clinical practice. Despite a high prevalence, comprehensive insights into their clinical presentation, management strategies, impact of multimodality imaging, and outcomes are not well established, due to a lack of dedicated studies. Methods and results The ‘EACVI-MMVD Study’ will be a large prospective, multicentre, observational cohort study led by the Heart Imagers of Tomorrow of the European Association of Cardiovascular Imaging (EACVI). It will assess the proportion, management, and prognosis of MMVD over a 1-year period of follow-up. All consecutive patients diagnosed with MMVD using transthoracic echocardiography will be recruited over a 6-month recruitment period in 88 centres from 24 different countries. Baseline evaluation will be determined by physicians and encompass the whole spectrum of multimodality imaging including transthoracic and transoesophageal echocardiography, stress echocardiography, computed tomography, and cardiovascular magnetic resonance. Centres will have the opportunity to send cardiovascular imaging data for core laboratory analysis and to extend recruitment throughout a 5-year follow-up period. Conclusion The EACVI-MMVD study will be the largest international multicentre study evaluating the prevalence of MMVD in clinical routine and determining the impact of multimodality cardiovascular imaging in MMVD patients. Clinical Trial Registration: NCT06235385 URL: https://classic.clinicaltrials.gov/ct2/show/NCT0623538
Seminal Interleukin-6 as a Biomarker of Inflammation, Oxidative Stress, and Sperm Dysfunction in Infertile Men
No full textInternational audienceBackground/Objectives: Interleukin-6 (IL-6), a pleiotropic cytokine involved in immune regulation, is consistently detected in human semen, even in the absence of overt infection. Its contribution to sperm dysfunction, oxidative stress, and inflammation remains incompletely understood. This study evaluated the associations between seminal IL-6 concentrations and markers of semen quality, oxidative stress, nuclear integrity, and genital tract inflammation in infertile men. Methods: A cohort of 204 infertile men was assessed. Seminal IL-6 was quantified by electrochemiluminescence immunoassay. Semen parameters, malondialdehyde (MDA), catalase (CAT) activity, sperm DNA fragmentation index (DFI), sperm chromatin decondensation index (SDI), leukocytospermia, and bacteriospermia were measured. Analyses included correlation testing, IL-6 threshold stratification (<30, 30–60, 60–100, ≥100 pg/mL), and multivariate regression. Results: IL-6 was detectable in all samples (median: 31.52 pg/mL; range: 1.5–5000 pg/mL). Higher IL-6 levels were significantly associated with reduced sperm concentration, progressive motility, and vitality, and with increased DFI, SDI, MDA, leukocyte counts, and bacteriospermia (p < 0.001). In multivariate models, IL-6 independently predicted reduced progressive motility (β = −0.005; p = 0.032) and elevated leukocyte count (β = 0.0018; p < 0.0001). Logistic regression further showed that IL-6 increased the odds of DFI ≥ 30%, SDI ≥ 30%, and bacteriospermia (p < 0.05). Conclusions: Seminal IL-6 emerges as a sensitive biomarker of immuno-oxidative stress and sperm dysfunction in infertile men. Its integration into clinical evaluation may improve the assessment of inflammatory and oxidative contributors to male infertility
Understanding the Universe Without Dark Matter and Without the Need to Modify Gravity: Is the Universe an Anamorphic Structure?
No full textInternational audienceWe envision a minimalist way to explain a number of astronomical facts associated with the unsolved missing mass problem by considering a new phenomenological paradigm. In this model, no new exotic particles need to be added, and the gravity is not modified; it is the perception that we have of a purely Newtonian (or purely Einsteinian) Universe, dubbed the Newton basis or Einstein basis (actually “viewed through a pinhole” which is “optically” distorted in some manner by a so-called magnifying effect). The κ model is not a theory but rather an exploratory technique that assumes that the sizes of the astronomical objects (galaxies and galaxy clusters or fluctuations in the CMB) are not commensurable with respect to our usual standard measurement. To address this problem, we propose a rescaling of the lengths when these are larger than some critical values, say >100 pc - 1 kpc for the galaxies and ∼1 Mpc for the galaxy clusters. At the scale of the solar system or of a binary star system, the κ effect is not suspected, and the undistorted Newtonian metric fully prevails. A key point of an ontological nature rising from the κ model is the distinction which is made between the distances depending on how they are obtained: (1) distances deduced from luminosity measurements (i.e. the real distances as potentially measured in the Newton basis, which are currently used in the standard cosmological model) and (2) even though it is not technically possible to deduce them, the distances which would be deduced by trigonometry. Those “trigonometric” distances are, in our model, altered by the kappa effect, except in the solar environment where they are obviously accurate. In outer galaxies, the determination of distances (by parallax measurement) cannot be carried out, and it is difficult to validate or falsify the kappa model with this method. On the other hand, it is not the same within the Milky Way, for which we have valuable trigonometric data (from the Gaia satellite). Interestingly, it turns out that for this particular object, there is strong tension between the results of different works regarding the rotation curve of the galaxy. At the present time, when the dark matter concept seems to be more and more illusive, it is important to explore new ideas, even the seemingly incredibly odd ones, with an open mind. The approach taken here is, however, different from that adopted in previous papers. The analysis is first carried out in a space called the Newton basis with pure Newtonian gravity (the gravity is not modified) and in the absence of dark matter-type exotic particles. Then, the results (velocity fields) are transported into the leaves of a bundle (observer space) using a universal transformation associated with the average mass density expressed in the Newton basis. This approach will make it much easier to deal with situations where matter is not distributed centrosymmetrically around a center of maximum density. As examples, we can cite the interaction of two galaxies or the case of the collision between two galaxy clusters in the bullet cluster. These few examples are difficult to treat directly in the bundle, especially since we would include time-based monitoring (with an evolving κ effect in the bundle). We will return to these questions later, as well as the concept of average mass density at a point. The relationship between this density and the coefficient κ must also be precisely defined
Optimal cut-off point of left ventricular ejection fraction for prediction of death in end-stage hypertrophic cardiomyopathy with systolic dysfunction
No full textInternational audienceBackground: In hypertrophic cardiomyopathy (HCM), end-stage disease is traditionally defined by a left ventricular ejection fraction (LVEF) below 50%. This cut-off point is widely used and supported by observational data linking it to increased mortality. However, this binary definition may oversimplify the continuum of systolic dysfunction and fail to accurately capture its prognostic significance. We aim to determine the optimal cut-off point of LVEF for predicting long-term all-cause mortality in a large cohort of consecutive end-stage HCM patients.Methods: All patients referred for cardiovascular magnetic resonance (CMR) assessment of HCM at three French university hospitals between 2008 and 2024 were retrospectively screened. All patients with HCM and LVEF < 50% were included. The primary endpoint was all-cause mortality using the National Registry of Death. A conditional inference tree (C-Tree) and Youden index method were applied to identify the optimal cut-off point of LVEF for predicting all-cause mortality. A propensity score matching approach was applied to optimize covariate balance between groups, ensuring standardized mean differences < 0.1. Cox proportional hazards models were used both before and after propensity score matching, as well as after adjustment for traditional prognostic factors. A restricted cubic spline model assessed the continuous relationship between LVEF and all-cause mortality, adjusted for covariates used in the Cox model.Results: Among 2,875 eligible patients with HCM, we included 691 patients (mean age 53 ± 7 years, 54% male) with a LVEF < 50% for the study. The optimal cut-off point of LVEF for predicting all-cause mortality was 40% with both methods. Among those, 492 patients had a LVEF of 40–50%, and 199 a LVEF < 40%. The patients with LVEF < 40% had more advanced structural and functional abnormalities: larger LV end-diastolic volumes (LVEDV indexed 99 ±11 vs 83 ±7 mL/m², p< 0.001), higher prevalence of right ventricular dysfunction (28% vs 5%, p< 0.001), and greater presence (66% vs 26%) and extent (2.4 ± 1.9 vs 0.6 ± 1.2 segments; p< 0.001) of late gadolinium enhancement (LGE). After propensity score matching, two groups of 191 patients were obtained, with comparable baseline characteristics. After a median follow-up of 9 years (IQR 6–11), 226 patients died (32%). After adjustment for traditional prognostic factors, a LVEF value < 40% was strongly associated with increased mortality before and after propensity score matching (HR: 23.6 [95% CI: 14.6–38.1]; p< 0.001 and HR: 20.5 [95% CI: 12.4-33.9], p< 0.001 respectively) (Figure 1). Annualized mortality rate was strongly higher with LVEF< 40% (15.1 versus 0.7, p< 0.001).Conclusion: In this large multicenter cohort of end-stage HCM patients, a LVEF cut-off point of 40% delineated a subgroup with substantially increased mortality, which remained significant after adjustment for traditional prognostic factors and was confirmed following propensity score matching