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Elaboration and Characterization of WMoTaNb High Entropy Alloy Prepared by Powder Metallurgy Processes
No full textInternational audienceThis work concerns the sintering of tungsten-based (i.e WMoTaNb) high entropy alloy (HEA) powders using the spark plasma sintering (SPS) technique and their mechanical properties. The synthesis was performed by a self-propagating high-temperature synthesis (SHS) type reaction in which the mixture of metallic oxides (WO3, MoO3 …) is reduced by magnesium. For this, a specific reactor has been developed. Different conditions including the addition of a moderator were tested. These powders are then densified by SPS technology which allows for keeping the initial microstructure of the powder. The optimization of sintering conditions was performed with the objective to control simultaneously the chemical composition, the grain growth and the densification stages
Process Development and Manufacturing: CHARACTERIZATION OF THE ACOUSTIC CONTRAST FACTOR: A NEW APPROACH FOR A LABEL-FREE SEPARATION OF THE STROMAL VASCULAR FRACTION
No full textGenetic landscape of a large cohort of Primary Ovarian Insufficiency: New genes and pathways and implications for personalized medicine
No full textInternational audienceBackgroundPrimary Ovarian Insufficiency (POI), a public health problem, affects 1-3.7% of women under 40 yielding infertility and a shorter lifespan. Most causes are unknown. Recently, genetic causes were identified, mostly in single families. We studied an unprecedented large cohort of POI to unravel its molecular pathophysiology.Methods375 patients with 70 families were studied using targeted (88 genes) or whole exome sequencing with pathogenic/likely-pathogenic variant selection. Mitomycin-induced chromosome breakages were studied in patients’ lymphocytes if necessary.FindingsA high-yield of 29.3% supports a clinical genetic diagnosis of POI. In addition, we found strong evidence of pathogenicity for nine genes not previously related to a Mendelian phenotype or POI: ELAVL2, NLRP11, CENPE, SPATA33, CCDC150, CCDC185, including DNA repair genes: C17orf53(HROB), HELQ, SWI5 yielding high chromosomal fragility. We confirmed the causal role of BRCA2, FANCM, BNC1, ERCC6, MSH4, BMPR1A, BMPR1B, BMPR2, ESR2, CAV1, SPIDR, RCBTB1 and ATG7 previously reported in isolated patients/families. In 8.5% of cases, POI is the only symptom of a multi-organ genetic disease. New pathways were identified: NF-kB, post-translational regulation, and mitophagy (mitochondrial autophagy), providing future therapeutic targets. Three new genes have been shown to affect the age of natural menopause supporting a genetic link.InterpretationWe have developed high-performance genetic diagnostic of POI, dissecting the molecular pathogenesis of POI and enabling personalized medicine to i) prevent/cure comorbidities for tumour/cancer susceptibility genes that could affect life-expectancy (37.4% of cases), or for genetically-revealed syndromic POI (8.5% of cases), ii) predict residual ovarian reserve (60.5% of cases). Genetic diagnosis could help to identify patients who may benefit from the promising in vitro activation-IVA technique in the near future, greatly improving its success in treating infertility
La datation des glissements de terrain paraglaciaires en Islande
No full textInternational audienceLa fonte des glaciers islandais à partir de 15ka a été suivi par des ajustements paraglaciaires dont les glissements de terrain représentent une des manifestations les plus emblématiques. Un travail d’inventaire de leur répartition spatiale permet de comptabiliser plusieurs centaines de glissements, dont 158 dans la région du Skagafjörður au Nord de l’île, 186 dans les Westfjords et 290 dans les fjords de l’est. Les logiques spatiales de leur répartition permettent de montrer un contrôle lithologique à l’échelle globale avec une surreprésentation des glissements dans les basaltes d’âge tertiaire dans des régions où les contrastes topographiques sont par ailleurs majeurs à l’échelle de l’île. Au-delà de ces éléments spatiaux, la question de l’âge de leur mise en place se pose. Si l’on compare la chronologie de la déglaciation de l’Islande avec la répartition spatiale des glissements, nous observons une décroissance de l’occurrence potentielle des glissements de terrain avec le temps. La majorité des glissements se localisent le long des versants qui ont été libérés au tout début de la déglaciation. A l’échelle des glissements eux-mêmes, des études ponctuelles permettent de préciser l’âge de leur mise en place. Différentes approches sont alors mobilisées. La première prédate les glissements en utilisant l’emboîtement des formes géomorphologiques et l’âge des plages soulevées par le rebond glacio-isostatiques sur lesquelles viennent mourir les dépôts des glissements de terrain. La seconde série de mesures postdate les glissements. En effet, des dépressions au sein des glissements ont piégé des cendres volcaniques datées et des végétaux piégés dans des tourbières. Ainsi, par téphrochronologie et datation radiocarbone, il est possible d’obtenir des dates pour caler les événements gravitaires. Les modèles âge-profondeur sont également utilisés pour affiner les résultats. Ainsi, les glissements de terrain islandais, datés avec plus ou moins de précisions, donnent des âges postglaciaires compatibles avec le schéma d’une mise en place paraglaciaire dans les tous premiers temps de l’Holocène
Violent suicide attempt history in elderly patients with bipolar disorder: The role of sex, abdominal obesity, and verbal memory: Results from the FACE-BD cohort (FondaMental Advanced center of Expertise for Bipolar Disorders)
No full textInternational audienceBackground: Bipolar disorder (BD) is a chronic, lifelong condition, associated with increased risk of obesity, cognitive impairment, and suicidal behaviors. Abdominal obesity and a higher risk of violent suicide attempt (SA) seem to be shared correlates with older age, BD, and male sex until middle age when menopause-related female body changes occur. This study aimed at assessing the role of abdominal obesity and cognition in the violent SA burden of individuals with BD.Methods: From the well-defined nationwide cohort FACE-BD (FondaMental Advanced center of Expertise for Bipolar Disorders), we extracted data on 619 euthymic BD patients that were 50 years or older at inclusion. Cross-sectional clinical, cognitive, and metabolic assessments were performed. SA history was based on self-report.Results: Violent SA, in contrast to non-violent and no SA, was associated with higher waist circumference, abdominal obesity and poorer California Verbal Learning Test short-delay free recall (CVLT-SDFR) (ANOVA, p < .001, p = .014, and p = .006). Waist circumference and abdominal obesity were associated with violent SA history independently of sex, BD type and anxiety disorder (Exp(B) 1.02, CI 1.00-1.05, p = .018; Exp(B) 2.16, CI 1.00-4.64, p = .009, accordingly). In an exploratory model, waist circumference and CVLT-SDFR performance mediated the association between male sex and violent SA.Limitations: Cross-sectional design and retrospective reporting.Conclusions: Violent SA history was associated with abdominal obesity and poorer verbal memory in older age BD patients. These factors were interlinked and might mediate the association between male sex and violent SA
Challenges and opportunities for crowdfunding in emerging markets : an ethical perspective
No full textInternational audienceStill marginal 10 years ago, crowdfunding is now growing and represents a larger share of the economy each year, especially in emerging markets. At the same time, research on alternative investments in emerging markets is growing at a much faster pace than other similar fields. Indeed, policymakers, investors, and entrepreneurs from emerging markets need to gain a better understanding about the impact of fundraising innovations on sustainable growth in their home countries to facilitate entrepreneurship, growth, and employment. In this chapter, we will firstly review the foundations of crowdfunding as an innovative model, the importance of ethics in this model as well as the responses of regulators to adapt the legislative frameworks in developing countries. Secondly, we will address the question of ethics that characterizes the crowdfunding platform sector today through a double response based both on the stakeholder theory and on the corporate governance theory