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The Monte Carlo method is widely used for the estimation of uncertainties in mechanical engineering design. However, while flexible, this method remains impractical in terms of computational time and scalability. To bypass these limitations, other more efficient approaches such as the Galerkin stochastic finite element method (GSFEM) or the collocation method have been proposed. GSFEM provides accurate output statistics, has the advantage of being sampling independent and can be modular in terms of operations, albeit code intrusive. While linear elasticity has been extensively covered in the literature, the application of GSFEM to nonlinear mechanical behaviour remains relatively unexplored, in part due to the difficulty to capture nonlinear effects with the traditional GSFEM interpolants. To this end, we propose a seamless and efficient modular framework avoiding the need to know a priori the material law. In particular, the method makes use of a wavelet based formulation able to capture simultaneously continuous and discontinuous behaviours, and stochastic operators are proposed to straightforwardly adapt any material model. Finally, the flexibility of this approach is illustrated with two problems: (i) a 3D hyperelastic example with nonlinear behaviour arising from buckling uncertainty, and (ii) the evaluation of the displacement of a point within a structure based on how much of the external accessible structural deformation is known.

A modular pipeline for improving the constitutive modelling of composite materials is proposed.The method is leveraged here for the development of subject-specific spatially-varying brain white matter mechanical properties. For this application, white matter microstructural information is extracted from diffusion magnetic resonance imaging (dMRI) scans, and used to generate hundreds of representative volume elements (RVEs) with randomly distributed fibre properties. By automatically running finite element analyses on these RVEs, stress-strain curves corresponding to multiple RVE-specific loading cases are produced. A mesoscopic constitutive model homogenising the RVEs’ behaviour is then calibrated for each RVE, producing a library of calibrated parameters against each set of RVE microstructural characteristics. Finally, a machine learning layer is implemented to predict the constitutive model parameters directly from any new microstructure. The results show that the methodology can predict calibrated mesoscopic material properties with high accuracy. More generally, the overall framework allows for the efficient simulation of the spatially-varying mechanical behaviour of composite materials when experimentally measured location-specific fibre geometrical characteristics are provided.

International audience; The first contractile waves in the developing embryonic gut are purely myogenic; they only involve smooth muscle. Here, we provide evidence for a transition from smooth muscle to interstitial cell of Cajal (ICC)-driven contractile waves in the developing chicken gut. In situ hybridization staining for anoctamin-1 (ANO1), a known ICC marker, shows that ICCs are already present throughout the gut, as from embryonic day (E)7. We devised a protocol to reveal ICC oscillatory and propagative calcium activity in embryonic gut whole mount and found that the first steady calcium oscillations in ICCs occur on (E14). We show that the activation of ICCs leads to an increase in contractile wave frequency, regularity, directionality, and velocity between E12 and E14. We finally demonstrate that application of the c-KIT antagonist imatinib mesylate in organ culture specifically depletes the ICC network and inhibits the transition to a regular rhythmic wave pattern. We compare our findings to existing results in the mouse and predict that a similar transition should take place in the human fetus between 12 and 14 wk of development. Together, our results point to an abrupt physiological transition from smooth muscle mesenchyme self-initiating waves to ICC-driven motility in the fetus and clarify the contribution of ICCs to the contractile wave pattern. NEW & NOTEWORTHY We reveal a sharp transition from smooth muscle to interstitial cell of Cajal (ICC)-driven motility in the chicken embryo, leading to higher-frequency, more rhythmic contractile waves. We predict the transition to happen between 12 and 14 embryonic wk in humans. We image for the first time the onset of ICC activity in an embryonic gut by calcium imaging. We show the first KIT and anoctamin-1 (ANO1) in situ hybridization micrographs in the embryonic chicken gut. Copyright © 2020 the American Physiological Society

Currently, the RA government is undertaking a number of measures in order to draw the agriculture in the republic out of unfavorable conditions, and to provide its future development which in its turn will help to increase the population.

Abstract. The aim of this study is to evaluate the effect of α-tocopherol supplementation at two doses (600 and 1200 mg × kg–1) on kidney antioxidant status and the histopathological changes in Wistar rats after 12 weeks of exposure at different diets. Forty rats has been divided into 4 groups of 10 rats each, the control group received basal diet with 5 % fresh sunflower oil (FSO), the second group: 5 % oxidized sunflower oil (OSO), the third group: 5 % OSO supplemented with 600 mg × kg–1 α-tocopherol and the fourth group: 5 % OSO supplemented with 1200 mg × kg–1 α-tocopherol. In OSO groups, the results showed highly significant increases of LPO (from 31.3 ± 0.9 to 53.8 ± 1.2 nmol of MDA formed/min/mg protein, p < 0.0001) with a significant decrease (p < = 0.001) of the antioxidant enzymatic activities (CAT, SOD, GPX, GR and G6PDH), body weight (339 ± 9 to 290 ± 3 g) and α-tocopherol levels (13.6 ± 0.6 to 6.5 ± 0.4 μg/mg protein). In OSO groups with 600 mg × kg–1 α-tocopherol, an antioxidant effect was found, reflected by a return of the parameters to values similar to those of the control group. However, higher doses of α-tocopherol (1200 mg × kg–1) induced a depletion of antioxidant status, α-tocopherol levels (6.0 ± 0.3 μg/mg protein, p < 0.001) and a very highly significant rise (p < 0.0001) of LPO content (54.86 ± 0.01 nmol of MDA formed/min/mg protein). The kidney tissues also showed changes in glomerular, severe inflammatory cells infiltration, and formation of novel vessels. So, we can conclude that the oxidative stress is attenuated by a moderate administration of 600 mg × kg–1 α-tocopherol, while a pro-oxidant effect occurs at 1200 mg × kg–1 α-tocopherol.

Orofacial dysfunction and parafunctions are responsible for many orthodontic abnormalities right from the stage of deciduous teeth.Incisor malocclusion, dental malposition and alveolar arch malformations are the most common abnormalities.Functional rehabilitation for prevention or as part of interceptive orthodontics significantly reduces the risk of appearance or progression of these abnormalities to more extensive malocclusions that are more difficult to manage.Functional rehabilitation consists of re-educating and restoring physiological orofacial functions, such as speech and swallowing, breathing and/or chewing disorders.

Functional orthodontic trainer use depends on its various indications. It allows the interception of orthodontic malocclusions, the contributions are numerous

Orofacial dysfunction and parafunctions are responsible for many orthodontic abnormalities right from the stage of deciduous teeth.Incisor malocclusion, dental malposition and alveolar arch malformations are the most common abnormalities.Functional rehabilitation for prevention or as part of interceptive orthodontics significantly reduces the risk of appearance or progression of these abnormalities to more extensive malocclusions that are more difficult to manage.Functional rehabilitation consists of re-educating and restoring physiological orofacial functions, such as speech and swallowing, breathing and/or chewing disorders.

Autour des affrontements entre positions internalistes ou externalistes du jeu vidéo, il s’agit d’envisager la jouabilité au croisement de deux sens possibles. L’un, technique, s’attache à décrire la maniabilité du programme informatique pour son utilisateur. L’autre décrit la réalisation d’un état ludique entre la structure et le joueur. Notre analyse d’un jeu vidéo (Super Meat Boy) indique comment la maniabilité est créatrice d’espaces de jeux à investir pour le joueur. La fonction replay de ce jeu exemplifie les accumulations non linéaires qui constituent l’expérience de jeu. Dans ces itérations de parties se dessinent des brouillons qui témoignent de l’activité ludique. Cette génétique de la pratique vidéoludique permet de proposer une coïncidence de ces deux sens du jouable., Based on the arguments between internalist or externalist conceptions of video games, this paper considers « playability » at the crossroads of two possible meanings. A technical one, describing the software’s gameplay for its user. Another one depicting the making of a gaming state between the game’s structure and the player. The analysis of a video game (Super Meat Boy) shows how playability creates game spaces which the player can invest. The replay feature is a perfect example of the non-linear gathering of experiences that is gaming. In those iterations of game sessions drafts are appearing, witnesses to the gaming activity. This genetic approach of videogaming allows us to suppose a matching for the two different senses of « playability »., Interfaces numériques, 4(1), 2015

Tomato seeds are the major constituents of the waste processing industry in tomato fruits, they represent 0.5% of the weight of the fruit and contain between 18 and 30% fat. The purpose of this work is the characterization and extraction of tomato seed oil. Tomato seed utilized in this experiment came from a pile waste in storage at the cannery Ammour – MouzaA¯a – Algeria. After separation, screening and dry in air, tomato seeds are placed in a device Soxhelet containing n-hexane as extraction solvent. The extraction yield was calculated and is 209.88 g of oils from 934.06 g seeds, or 22.47%. After filtration, efficiency is 21.47% representing 82% of fat tomato seeds. Physicochemical properties of the oil quality were measured before and after refining, it appears that refining reduces the acidity of 0.9 to 0.06%, the chlorophyll content of 15.46 to 0.0092% and causes the disappearance of phosphorus. The result of the chromatographic analysis of the lipid fraction of tomato seed oil showed a chromatographic profile composed of 07 fatty acids from 16 to 18 carbon atoms. The linoleic and oleic acids predominates with 52 and 22% respectively, saturated fatty acids are essentially represented by palmitic acid (13.18%) and stearic acid (6.18%). Finally, the induction time estimated by the Rancimat test, characteristic of stability and resistance of oxidation 4.7 h at 120°C, corresponding durability of 223 days at 20°C.