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On uniqueness of solutions to complex Monge–Ampère mean field equations
No full textInternational audienceWe establish the uniqueness of solutions to complex Monge-Amp\`ere mean field equations when the temperature parameter is small. In the local setting of bounded hyperconvex domains, our result partially confirms a conjecture by Berman and Berndtsson. Our approach also extends to the global context of compact complex manifolds
Early stage of metabolic dysfunction associated steatotic liver disease disrupts circadian rhythm and induces neuroinflammation in rats
No full textInternational audienceMetabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is a chronic liver disease affecting 25% of the European population, with rising global incidence. Liver damage includes ballooning, steatosis, inflammation and fibrosis. Associated brain disorders include sleep, cognitive issues, anxiety, and depression. While neurological complications in advanced MASLD are well documented, early cerebral manifestations remain largely unexplored. This study aimed at developing an MASLD rat model to assess the onset of early brain damage, focusing on impairments of the circadian cycle rhythm and associated neuroinflammation. Sprague Dawley rats were divided into two groups: one received a high-fat, high-cholesterol (HFHC) diet for 90 days, while the other received a standard diet. Histological analysis showed significant hepatic steatosis, ballooning, and inflammation in the HFHC group (p < 0.01). These lesions correlated with elevated hepatic triglycerides (p < 0.01), increased Alanine Aminotransferase, Aspartate Aminotransferase, total cholesterol, and low-density lipoprotein, alongside decreased plasma high-density lipoprotein. Behavioural analysis using activity wheels revealed that the HFHC rats steadily maintained their activity level during the rest periods when compared with controls (p < 0.05). This behavioural alteration occurred alongside neuroinflammation, demonstrated by changes in the expression of 36 and 17 inflammatory mediators in the cerebellum and frontal cortex respectively. These changes were associated with an increase in the expression of glial cell markers (Aif1 and Gfap genes) and an increase in the number of microglial cells, affecting the frontal cortex and cerebellum differently. This rat model of early MASLD shows circadian rhythm disturbances, which could reflect sleep disorders in humans. These early brain disturbances specific to MASLD, which occur before the symptoms of liver disease become clinically apparent, could therefore be used as an early diagnosis marker for MASLD patients
Graphite-Based Localized Heating Technique for Growing Large Area Methylammonium Lead Bromide Single Crystalline Perovskite Wafers and Their Charge Transfer Characteristics
No full textInternational audienceDevelopment of a reproducible technique to grow large area single crystalline perovskite wafers is an open research gap in the field of single crystalline perovskite solar cells. A graphite-based localized heating technique for growing large area methylammonium lead bromide (CH3NH3PbBr3; MAPBr) single crystalline thin film (SCTF) on different buffer layers, such as glass/indium doped tin oxide (ITO), glass/ITO/poly(triaryl amine) (PTAA), and glancing angle deposition (GLAD) coated glass/ITO/TiO2 substrates is reported, and their charge transport properties are discussed. It is observed that the localized heating technique can confine the supersaturation of the precursor mainly to the center of the substrate, leading to a restricted number of nucleations within a specific area on the substrate. Here, such 2-3 seed crystals obtained initially are allowed to grow to a larger size of up to 65 mm2. The X-ray diffraction (XRD) analysis indicated that the large area SCTF is an actual single crystal and not a heterogeneous group of small crystals merged together with a crystallinity index (CI) of 92.60 +/- 0.11% which was comparable to that of the bulk single crystal (97.74 +/- 0.47%). The atomic force microscopy (AFM) image depicted a smooth SCTF surface (R a = 4.37 +/- 0.01 nm), and the wave-like pattern is attributed to the substrate morphology, implying that the topography of the substrate plays a crucial role in obtaining a planar SCTF. The XRD, UV-visible, photoluminescence (PL), Raman, and FTIR spectra analyses revealed that the large area SCTF is phase pure and free of residual impurities. The charge injection characteristics of the SCTFs grown on different buffer layers were investigated using PL emission (PLE) and PL decay analyses. The decrease in the PLE intensity for the SCTFs grown on PTAA and TiO2 substrates implied exciton quenching behavior, indicating the injection of the photogenerated charge carriers into the charge transfer layers (CTLs). The decrease of the fast decay component from tau 1 = 4.77 +/- 0.18 ns for glass to tau 1 = 3.32 +/- 0.07 ns for TiO2 and tau 1 = 3.15 +/- 0.33 ns for PTAA is ascribed to the interfacial recombination of the charges accumulated at the CTL/perovskite interface. These results propose that the localized heating technique can be employed for growing large area single crystalline perovskite wafers for optoelectronic and photovoltaic device applications
Luttes contre les fraudes à la TVA, des leçons tirées de la série D'argent et de sang
No full textInternational audienceCet article analyse l'utilisation de la série télévisée D'Argent et de Sang comme un outil pédagogique novateur pour enseigner la finance et la fiscalité. La série retrace l'affaire du carousel de TVA sur le marché des quotas carbone, une des plus grandes fraudes fiscales françaises, en explorant les failles réglementaires et les interactions complexes entre les acteurs étatiques, financiers et criminels. À travers des personnages fictifs mais inspirés de faits réels, la série illustre des concepts techniques tels que la TVA, les marchés financiers, le blanchiment d'argent, tout en sensibilisant aux dimensions éthiques et sociales des pratiques frauduleuses.L'étude repose sur une analyse qualitative des contenus de la série, mise en perspective avec des données historiques et institutionnelles. Elle démontre que ce type de support narratif favorise l'engagement des étudiants et rend accessibles des notions financières souvent perçues comme abstraites ou complexes. En intégrant ces concepts dans un récit immersif, la série aide les apprenants à mieux comprendre les mécanismes de fraude, les enjeux de régulation des marchés, ainsi que les dilemmes éthiques auxquels font face les professionnels et les décideurs politiques. Toutefois, elle soulève aussi des défis : les biais narratifs et les simplifications peuvent induire des interprétations erronées si elles ne sont pas accompagnées d'un encadrement pédagogique rigoureux.En conclusion, l'article souligne que D'Argent et de Sang constitue un levier pédagogique pour enrichir l'enseignement de la finance et susciter un dialogue sur des sujets contemporains, tels que la pertinence de la TVA sur les marchés financiers ou l'impact de la finance verte sur les objectifs climatiques. En dépit des limites liées à l'usage de supports fictionnels, cette approche innovante représente une opportunité pour améliorer la compréhension critique et l'engagement des futurs professionnels de la gestion
Cross-Analytical Strategies to Tackle "Medicines in Disguise" Presented as Food Supplements, a New Threat for Human Health
No full textInternational audiencePlant-based food supplements (FS) of doubtful traceability have now emerged as a new threat to human health. Food supplements adulterated with pharmaceutical ingredients are considered "medicines in disguise" by regulatory authorities, which is a sub-category of falsified medicines. In the context of illegal manufacture and trade, as well as in the absence of an official phyto-and/or pharmacovigilance system, emergency departments and poison control centers constitute a early warning system for detecting ingested suspect FS. In the present investigation, we set up efficient workflows for the systematic characterization of adulterated plant-based FS in the context of an original local early warning alert system (i.e., FalsiMedTrack) involving an emergency department, a poison center, and academic analytical chemistry laboratories. Fit-for-purpose cross-analytical methods were employed, including sophisticated methods such as liquid chromatography coupled to high-resolution mass spectrometry, nuclear magnetic resonance, Xray powder diffraction, as well as the most accessible and affordable HPLC method with UV/DAD detection. The strategy was applied successfully to typical cases of suspect plant-based health products, i.e., sample incriminated in patients experiencing side effects and herbal products currently commercialized for their "amazing health benefits". The samples contained active pharmaceutical ingredients, including diclofenac, piroxicam, dexamethasone 21-acetate, and sibutramine. We provided evidence of "medicines in disguise" presented as food supplements, which raises concerns about their quality and safety
Les clés d'une offre de produits bio transformés naturels et durables
No full texthttps://merveillogie.com/les-cles-dune-offre-de-produits-bio-transformes-naturels-et-durables/Selon le baromètre Greenflex (2023) (1), la santé est une préoccupation centrale pour les consommateurs. Toutefois, cette préoccupation tend à s’infléchir en raison d’un contexte en tension et inflationniste. Le prix est au demeurant le premier frein à la consommation des produits alimentaires issus de l’agriculture biologique (Baromètre Obsoco/Agence Bio, 2024) (2). Parallèlement, la part des produits transformés s'accroît dans le panier des consommateurs de bio : près des ¾ des produits bio vendus en France en 2023 sont des produits transformés (3). Or, ces produits affichent des prix plus élevés que les produits bruts, du fait de coûts de production plus élevés liés à davantage de main d’œuvre et d’investissements. Dès lors, comment se positionner au mieux pour répondre aux attentes des consommateurs qui ont une préférence pour les produits transformés mais dont le consentement à payer est de plus en plus limité ? Il n'existe pas de solution miracle mais une recherche récente conduite entre 2019 et 2024 nous invite à mettre l'accent sur plusieurs recommandations managériales à destination des transformateurs bio : il importe de bien étudier les représentations des consommateurs en matière de transformation alimentaire mais aussi de production biologique, afin de formuler une proposition de valeur pertinente (c’est-à-dire une offre dotée de bénéfices valorisés par les consommateurs ou en d’autres termes des gains qu’ils recherchent (un bon goût, un produit naturel, un produit bon pour la santé…) sans négliger pour autant la question de l'empreinte énergétique de la production
Early anatomo-functional correlations using voxel-based lesion-symptom mapping in children with left-sided stroke lesion
No full textCes travaux ont bénéficié d’un accès aux moyens de calcul de l’IDRIS au travers de l'allocation de ressources 2023-AD010314332 attribuée par GENCIInternational audienceVoxel-based lesion-symptom mapping (VLSM) has enabled previous studies to demonstrate relationships between lesion location and clinical outcomes such as dexterity in patients with right and left perinatal stroke but not with global motor functioning. There is evidence that infarct side has an impact on post-stroke brain development. The aim of this study is to investigate anatomo-functional relationship in a homogeneous paediatric population with left perinatal stroke lesion and global motor scores used in clinical practice.Brain imaging data was obtained from the CAP project, which included 110 children aged 2 to 4 years with cerebral palsy who underwent MRI before and after therapy. Among them, we segmented and normalised the lesions of 25 children with stroke and performed VLSM. For each voxel, a group comparison between patients with and without a lesion in that voxel was estimated using a Student's t-test. We used Gross Motor Function Measurement (GMFM) and its subscore E (which measures balance) as dependant variables and lesion size as a covariate. P-values were corrected for multiple comparisons with 1000 permutations of the behavioural scores.We found significant associations between GMFM and GMFM E and areas involved in the motor system, including the internal capsule and corona radiata. These findings suggest that motor determinants are established in anatomical structures early in brain development, highlighting the importance of preserving these regions to ensure global motor function. Targeted rehabilitation strategies are crucial to improving the care of children with stroke. Stimulating these specific structures may lead to a better recovery
A scoping review of circulating peptides assessments in anorexia nervosa: Uncovering diversity and nuanced findings
No full textInternational audienc
L’apport des données hydrodynamiques pour caractériser les tempêtes détectées au sein d’archives sédimentologiques et historiques
No full textInternational audienceL'étude et la datation précises des impacts sédimentologiques de dépôts de tempêtes situés dans des zones basses côtières en arrière de cordons dunaires constituent un défi important dans les environnements macrotidaux. Pour relever ce défi, nous proposons une méthode basée sur le croisement entre sédimentologie, analyse d'archives historiques, statistiques et modélisation hydrodynamique. Le site de la Petite Mer de Gâvres, dans le sud de la Bretagne, a été retenu comme étant un espace macrotidal pertinent le long de la côte atlantique française. L'analyse des carottes sédimentaires a permis d'identifier six dépôts de washover. Le croisement avec les données météo-marines de réanalyse et les sources historiques a suggéré qu'ils ont été causés par les événements de 1896, 1924, 1950, 1974, 1990 (quatre tempêtes) et 1999 (deux tempêtes). Ces hypothèses ont été confirmées par les données de réanalyse via le calcul de la période de retour conjointe des hauteurs significatives des vagues et des niveaux d'eau (marée + surcote) et l'utilisation de la formule de Stockdon pour estimer si le niveau de l'eau par rapport au niveau de la crête de dune. Pour toutes les tempêtes identifiées comme étant à l'origine des dépôts de washover datés, la hauteur significative des vagues était toujours exceptionnellement forte, soulignant l'effet clé de ce paramètre. Enfin, les avantages et les limites de cette méthode composite employée pour documenter les tempêtes historiques ont été soulignés ; notamment en mettant en lumière l'exemple du dépôt de tempête daté à 1973 ± 1.5an, qui était précédemment associé à l'évènement du 13 février 1972 mais qui a été corrigé avec celui du 11 février 1974 grâce aux modèles hydrodynamiques
Value of tacrolimus 0.1% in the treatment of vitiligo in the era of targeted therapy
No full textInternational audienceBackground: Vitiligo, a prevalent depigmenting condition, affects both adults and children, significantly impacting their quality of life. The standard treatment approach involves the application of topical corticosteroids in conjunction with narrow-band ultraviolet B (UVB) phototherapy. A novel topical treatment, ruxolitinib (a Janus kinase inhibitor), has recently received approval. Notwithstanding the absence of marketing authorization for this particular indication in France, numerous practitioners have adopted the use of tacrolimus ointment 0.1% for the treatment of vitiligo, frequently in conjunction with phototherapy. The objective of this study is to present the benefit/risk ratio of tacrolimus in the treatment of vitiligo.Methods: A comprehensive literature search was conducted by the Centre of Evidence (CDP) of the French Society of Dermatology (SFD) to ascertain the efficacy and safety of topical calcineurin inhibitors (TCIs) in vitiligo. The search strategy encompassed meta-analyses (MAs) and prospective multicentric cohort studies.Results: Literature data - in particular three meta-analyses and one randomised controlled trial - confirm the superiority of tacrolimus versus placebo and its non-inferiority versus super-potent topical corticosteroids. In a subgroup analysis, tacrolimus suggests superior efficacy in children and in facial vitiligo. The combined use of tacrolimus and phototherapy exhibited synergistic efficacy.Conclusion: Notwithstanding the market access of topical ruxolitinib, tacrolimus remains a viable treatment option for vitiligo, as substantiated by extant efficacy and safety in the literature. A recent decision of the French National Agency for the Safety of Medicines and Health Products (ANSM) authorized the compassionate prescription of tacrolimus and its reimbursement for patients