59 research outputs found
Recommandations de Conception issues du ContrĂŽle Non Destructif (RCC-MRx)
National audienceUne rĂ©flexion a Ă©tĂ© initiĂ©e en 2008 par les concepteurs de centrales nuclĂ©aires RNRrefroidies au sodium, avec lâaide de spĂ©cialistes du LCND (UniversitĂ© Aix-Marseille).Lâobjectif Ă©tait dâinsuffler une culture CND, un rĂ©flexe pour les besoinsdâinspectabilitĂ©/rĂ©parabilitĂ©. Le constat qui a motivĂ© cette rĂ©flexion Ă©tait que toutes les rĂšglesrelatives aux CND prĂ©sentes dans le code RCC-MR (Ă©dition 2007) Ă©taient spĂ©cifiquementdĂ©volues aux contrĂŽles de fabrication. Un Groupe de Travail ThĂ©matique (GTT) a produit fin2012 une rĂ©vision de lâAnnexe A20 «Dispositions constructives associĂ©es aux visites desurveillance en exploitation» du code RCC-MRx, rĂ©sultant de la fusion des codes RCC-MRet RCC-MX dĂ©diĂ© aux rĂ©acteurs expĂ©rimentaux. Cette rĂ©vision est volontairement peuprescriptive car le GTT a montrĂ© que, vis-Ă -vis de la complexitĂ© des problĂšmes posĂ©s, ledialogue entre concepteur, fabricant et contrĂŽleur semble ĂȘtre le meilleur moyen pour trouverun compromis entre conception, fabrication et besoin dâinspection en service. Le GTT aconsidĂ©rĂ© indispensable dâaccompagner cette Annexe dâun document qui fournisse lesfondements des recommandations (criteria), et qui permette de comprendre et justifier lessolutions apportĂ©es avec les moyens techniques de contrĂŽles actuels. Certaines mises enperspective sont Ă©galement indiquĂ©es. La prĂ©sente communication montre le principe de larĂ©vision retenue, et prĂ©sente quelques exemples extraits des criteria
Muscle inactivation of mTOR causes metabolic and dystrophin defects leading to severe myopathy
Mammalian target of rapamycin (mTOR) is a key regulator of cell growth that associates with raptor and rictor to form the mTOR complex 1 (mTORC1) and mTORC2, respectively. Raptor is required for oxidative muscle integrity, whereas rictor is dispensable. In this study, we show that muscle-specific inactivation of mTOR leads to severe myopathy, resulting in premature death. mTOR-deficient muscles display metabolic changes similar to those observed in muscles lacking raptor, including impaired oxidative metabolism, altered mitochondrial regulation, and glycogen accumulation associated with protein kinase B/Akt hyperactivation. In addition, mTOR-deficient muscles exhibit increased basal glucose uptake, whereas whole body glucose homeostasis is essentially maintained. Importantly, loss of mTOR exacerbates the myopathic features in both slow oxidative and fast glycolytic muscles. Moreover, mTOR but not raptor and rictor deficiency leads to reduced muscle dystrophin content. We provide evidence that mTOR controls dystrophin transcription in a cell-autonomous, rapamycin-resistant, and kinase-independent manner. Collectively, our results demonstrate that mTOR acts mainly via mTORC1, whereas regulation of dystrophin is raptor and rictor independent
Recommended from our members
Autistic perspectives on the future of clinical autism research
The Lancet Commission on the Future of Care and Clinical Research in Autism recently published their recommendations for what should be done in the next 5 years to address the current needs of autistic individuals and families. Although the Commission includes many prominent clinicians and researchers from around the world, as well as some autistic advocates and parents of autistic people, there have been widespread expressions of dissatisfaction among autistic people and communities regarding these recommendations.
We, the Global Autistic Task Force on Autism Research are a group of autistic professionals and representatives of organizations run by and for autistic people. We are autistic clinicians, therapists, educators and researchers, parents, and family members of autistic people of all ages and with all types of support needs, as well as individuals with high support needs. Among us are also autistic people of color, autistic people from the Global South and Asia, autistic women, and autistic people belonging to gender minorities.
Despite aiming at bringing together different stakeholders, representation within the Lancet Commission was limited in these respects. We hope to bring more voices to the discourse. We previously wrote an open letter to the Commission to draw attention to our main concerns. In this editorial, we offer a more detailed discussion of the Commission's report, as well as our own recommendations for future directions in autism research and care
Muscle inactivation of mTOR causes metabolic and dystrophin defects leading to severe myopathy
mTor, acting mainly via mTORC1, controls dystrophin transcription in a raptor- and rictor-independent mechanism
The Politics of (and Behind) the UNFCCCâs Loss and Damage Mechanism
Despite being one of the most controversial issues to be recently treated within climate negotiations, Loss and Damage (L&D) has attracted little attention among scholars of International Relations (IR). In this chapter we take the âstructuralist paradoxâ in L&D negotiations as our starting point, considering how IR theories can help to explain the somewhat surprising capacity of weak parties to achieve results while negotiating with stronger parties. We adopt a multi-faceted notion of power, drawing from the neorealist, liberal and constructivist schools of thought, in order to explain how L&D milestones were reached. Our analysis shows that the IR discipline can greatly contribute to the debate, not only by enhancing understanding of the negotiation process and related outcomes but also by offering insights on how the issue could be fruitfully moved forward. In particular, we note the key importance that discursive power had in the attainment of L&D milestones: Framing L&D in ethical and legal terms appealed to standards relevant beyond the UNFCCC context, including basic moral norms linked to island statesâ narratives of survival and the reference to international customary law. These broader standards are in principle recognised by both contending parties and this broader framing of L&D has helped to prove the need for action on L&D. However, we find that a change of narrative may be needed to avoid turning the issue into a win-lose negotiation game. Instead, a stronger emphasis on mutual gains through adaptation and action on L&D for both developed and developing countries is needed as well as clarity on the limits of these strategies. Examples of such mutual gains are more resilient global supply chains, reduction of climate-induced migration and enhanced security. As a result, acting on L&D would not feel as a unilateral concession developed countries make to vulnerable ones: it would rather be about elaborating patterns of collective action on an issue of common concern
Determination of a New Ultrasonic Indicator to Follow the Concrete Setting in Real Time
Knowing the setting of roller compacted concrete (RCC) is an essential element within the framework of the building of multi-layered structures such as dams.</p
Weld Inspection by Radioscopy: Computer Simulation and Automatic Segmentation
The present research concerns automatic control of the mechanical quality of a weld on a circumferential component. A method of image processing is developed that searches for the limits of the weld melted zone for each angular position, so as to extract the evolution in terms of the main geometric characteristics of the zone (penetration depth, etc...). It is an image segmentation operation since it achieves the extraction of useful elements for interpretation.</p
Energy Conscious Building Design for the Humid Subtropical Climate of Southern China
The present research concerns automatic control of the mechanical quality of a weld on a circumferential component. A method of image processing is developed that searches for the limits of the weld melted zone for each angular position, so as to extract the evolution in terms of the main geometric characteristics of the zone (penetration depth, etc...). It is an image segmentation operation since it achieves the extraction of useful elements for interpretation
Traitement numĂ©rique dâimages issues de contrĂŽles ultrasonores de haute frĂ©quence pour la caractĂ©risation inclusionnaire dâaciers Ă roulements
Les fabricants dâaciers Ă roulement cherchent toujours Ă optimiser leurs procĂ©dĂ©s dâĂ©laboration, en prenant notamment en compte le lien existant entre les endommagements en fatigue et la population dâinclusions non mĂ©talliques prĂ©sentes. On rĂ©duit ainsi le risque dâapparition dâun dĂ©faut qui compromet lâintĂ©gritĂ© mĂ©canique du roulement. Les tailles critiques de dĂ©fauts (Ă partir de 10 ou 15 ”m), et les volumes Ă sonder correspondant, posent des problĂšmes de dĂ©tection. Ces inclusions sont trop grosses et leur probabilitĂ© dâoccurrence trop faible pour ĂȘtre dĂ©tectĂ©es par les mĂ©thodes de caractĂ©risation de type spectroscopique ou mĂ©tallographique, et trop petites pour ĂȘtre dĂ©tectĂ©es avec des contrĂŽles ultrasonores mĂȘme de hautes frĂ©quences. On propose une mĂ©thode de traitement numĂ©rique dâimages ultrasonores qui permette dâamĂ©liorer la rĂ©solution de dĂ©tection, de maniĂšre automatique, et Ă une cadence compatible avec les contraintes industrielles existantes. Les images sont obtenues Ă partir dâun systĂšme dâĂ©chographie ultrasonore haute frĂ©quence (80 MHz). Le traitement numĂ©rique est basĂ© sur une exploitation de deux critĂšres statistiques de lâimage, la variance des gradients des signaux et lâĂ©cart temporel entre les extrĂ©ma de chaque signal. On prĂ©sente des rĂ©sultats de dĂ©tection obtenus sur des Ă©chantillons comportant des dĂ©fauts micromĂ©triques artificiels
Avancees sur la controlabilite ultrasonore des materiaux et des structures
National audienceLa controlabilite d'un materiau ou d'une structure peut etre definie comme la facilite avec laquelle ils peuvent etre examines de facon non destructive, avec un diagnostic fiable. Nos travaux precedents introduisaient la notion de RC-CND, Regles de Conception issues du CND, permettant de faciliter le controle des structures. Par exemple, la forme d'un composant, son accessibilite, doivent etre anticipees de maniere differente si l'on prevoit un controle ultrasonore, ou radiographique. Nos recherches actuelles portent sur la nouvelle notion de RE-CND, Regles d'Elaboration issues du CND, qui seraient introduites en amont, dans les specifications siderurgiques, afin d'obtenir une qualite CND suffisante pour qu'un materiau soit controlable, notamment en termes d'attenuation des ondes et de bruit de structure. Les pieces non controlables en phase de fabrication (donc rebutees) seraient ainsi evitees, de meme qu'en service apres endommagement. Nous definissons d'abord la qualite ultrasonore d'un materiau (methode CND la plus utilisee), qui s'appuie sur des mesures fiables des parametres attenuation et vitesse des ondes, et bruit de structure. Pour cela, nous presentons la complexite de realisation d'echantillons representatifs de la microstructure (taille du grain, macles, precipites ...). La hierarchisation de l'influence des parametres permet d'avancer dans la comprehension des phenomenes, en vue d'une application industrielle
- âŠ