The mitochondrial protease OMA1 acts as a metabolic safeguard upon nuclear DNA damage

The metabolic plasticity of mitochondria ensures cell development, differentiation, and survival. The peptidase OMA1 regulates mitochondrial morphology via OPA1 and stress signaling via DELE1 and orchestrates tumorigenesis and cell survival in a cell- and tissue-specific manner. Here, we use unbiased systems-based approaches to show that OMA1-dependent cell survival depends on metabolic cues. A metabolism-focused CRISPR screen combined with an integrated analysis of human gene expression data found that OMA1 protects against DNA damage. Nucleotide deficiencies induced by chemotherapeutic agents promote p53-dependent apoptosis of cells lacking OMA1. The protective effect of OMA1 does not depend on OMA1 activation or OMA1-mediated OPA1 and DELE1 processing. OMA1-deficient cells show reduced glycolysis and accumulate oxidative phosphorylation (OXPHOS) proteins upon DNA damage. OXPHOS inhibition restores glycolysis and confers resistance against DNA damage. Thus, OMA1 dictates the balance between cell death and survival through the control of glucose metabolism, shedding light on its role in cancerogenesis

L’abri sous-roche du Rozel (France, Manche) : un habitat de la phase récente du Paléolithique moyen dans son contexte géomorphologique

Situé sur la côte ouest du Cotentin (Manche), le site du Rozel a livré un complexe de deux niveaux d’occupations anthropiques. L’abri sous-roche conservait les vestiges d’un habitat comportant des structures de combustion, du mobilier lithique et fait exceptionnel dans le Cotentin des restes osseux. L’ensemble s’inscrit dans une formation dunaire sus-jacente à une plage ancienne.Initialement attribué à un Périgordien ancien, le site a fait l’objet d’une “ relecture ” visant à préciser son attribution chronostratigraphique et chronoculturelle.Le Rozel est actuellement le seul gisement de Basse-Normandie a avoir livré une industrie lithique à composante mixte. Les matières premières utilisées sont le quartz filonien prélevé à l’intérieur même de l’abri, et les galets de silex prélevés dans les cordons littoraux actifs à l’époque. Les générations successives de grands cordons littoraux formés au fur et à mesure de la régression weichsélienne ont été enfouies très rapidement par le massif dunaire, ne permettant plus l’exploitation de leur contenu, riche en nodules propices à la taille. Le débitage apparaît orienté, dans les deux niveaux, vers la production d’éclats prédéterminés (principalement Levallois) et d’enlèvements allongés. Un schéma opératoire laminaire de type paléolithique supérieur a été mis en évidence dans le niveau supérieur, lié à l’occupation principale de l’abri. Le site intègre l’ensemble des gisements à industrie laminaire de gestion volumétrique du début du Dernier Glaciaire. La faune représentée témoigne de conditions environnementales plutôt tempérées où l’aurochs, les cervidés et dans une moindre mesure les chevaux dominent. L’originalité du site réside dans la présence d’un fragment mandibulaire de morse, associé à l’occupation, témoignant de conditions subarctiques temporaires. L’analyse des vestiges de faune atteste de travaux de boucherie (découpe, fracturation des os longs) et traduit différents modes d’acquisition, ou des traitements particuliers en fonction des espèces.La convergence des observations effectuées dans les différentes disciplines indique que les occupations du site du Rozel se rapportent à la phase récente du Paléolithique moyen du début du dernier glaciaire weichsélien et non au Paléolithique supérieur initial.Located on the Western coast, the Rozel provided an archaeological complex characterized by two occupation levels. The shelter has preserved traces of a habitat with combustion structures, lithic tools, and faunal remains, an exception on the Cotentin peninsula. The settlement is located in littoral dune upon a complex raised beach.Initially attributed to an Early Perigordian occupation, this site has been reinvestigated from a stratigraphic and cultural point of view. The Rozel shelter is the only occupation in the region presenting a mixed lithic industry. The raw materials used for tools are vein quartz found inside the shelter, and flint cobbles from the active gravel ridges. The successive gravels ridges raised step by step during the weichselian regression were rapidly buried by drift dune sands limiting exploitation of there high content of suitable flint knapping nodules.. In the two occupation layers “debitage” seems to be oriented to the production of predeterminated flakes (manly Levallois technique) and elongated flakes. An operating procedure ‘laminaire de type paléolithique supérieur’, has been revealed in the upper floor, in relation with the main occupation of the site. Le Rozel is an integral part of the series if sites presenting volumetric blade industries from the beginning of the Weichselian. The preserved fauna attests of mostly temperate environments dominated by wild ox, deer and some horses. The particular interest of this site is the occurrence of a fragment of walrus bone in association with the occupation attesting of temporary subarctic climatic conditions. Analysis of the faunal remains attests to various slaughtering and butchering techniques indicating different methods used according to species. All these multidisciplinary approaches assign all of Le Rozel shelter occupations to the beginning of the Weichselian, not to the Early Upper Palaeolithic

Investigation of asymmetric vortex pair interactions

Two-dimensional vortex interactions and merging in fluid flows have long been a subjectof significant research interest, with particular focus on clarifying their role in the inverse energy cascade of two-dimensional turbulence. Previous research has generally taken one of two forms: detailed study of the interaction of two vortices in isolation, or macroscopic study of a field of many vortices. Bridging the gap between these has been difficult, due to the complexity of the two-vortex, i.e., vortex pair, interaction and its varied outcomes when the vortices are unequal. In order to rectify this, this research considers in detail the interaction of two unequal co-rotating vortices in viscous fluid, and develops a method to quantitatively assess their outcomes. This enables a simple characterization of interaction outcomes in terms of certain key parameters. Using this, the case of a vortex pair interacting in linear shear which serves as a simple model of the background flow generated by a field of many vortices, is then studied. Collectively, this work establishes a method for studying the influence of background flow on interacting vortices.For the present research, numerical simulations are performed of vortex pairs having arange of vortex strength ratios in background flow having a linear shear velocity profile having a range of strengths, for finite Reynolds number. A method is introduced to monitor the flow development continuously, enabling the quantitative assessment of interaction outcomes in terms of an enhancement factor, ε, and a merging efficiency. η, which compare the circulations at the start and end of the convective interaction. The variation of these outcomes is found to be well-characterized by a mutuality parameter, a quantity directly related to the vortices’ enstrophy ratio. The presence of shear is then found to produce two distinct flow regimes: separation, in which the vortices move apart continuously, and hendition, in which they interact to form a single vortex similar to, and similarly characterized as in, the isolated-pair case. However, the presence of shear is observed to alter the timing of key physical interaction processes, which may in some cases significantly alter the ultimate outcome. Taken together, these findings imply a general framework for two-dimensional co-rotating vortex interactions that can be incorporated into turbulence models

Longitudinal Oscillator for Cardiac Arrest Victims (semester?), IPRO 332: Longitudinal Oscillator IPRO 332 Abstract F06

IPRO 332 begins an investigation of the use of mechanical shaker beds in a life-support capacity for beings with cardiac arrest. It will develop and continue research that was begun at the Miami Heart Research Institute, and will work in conjunction with researchers at IIT and the University of ChicagoDeliverables for IPRO 332: Longitudinal Oscillator for Cardiac Arrest Victims for the Fall 2006 semeste

Longitudinal Oscillator for Cardiac Arrest Victims (semester?), IPRO 332: Longitudinal Oscillator IPRO 332 Poster F06

IPRO 332 begins an investigation of the use of mechanical shaker beds in a life-support capacity for beings with cardiac arrest. It will develop and continue research that was begun at the Miami Heart Research Institute, and will work in conjunction with researchers at IIT and the University of ChicagoDeliverables for IPRO 332: Longitudinal Oscillator for Cardiac Arrest Victims for the Fall 2006 semeste

Longitudinal Oscillator for Cardiac Arrest Victims (semester?), IPRO 332: Longitudinal Oscillator IPRO 332 Final Report F06

IPRO 332 begins an investigation of the use of mechanical shaker beds in a life-support capacity for beings with cardiac arrest. It will develop and continue research that was begun at the Miami Heart Research Institute, and will work in conjunction with researchers at IIT and the University of ChicagoDeliverables for IPRO 332: Longitudinal Oscillator for Cardiac Arrest Victims for the Fall 2006 semeste