A family of higher-order single layer plate models meeting Cz0C^0_z -- requirements for arbitrary laminates

In the framework of displacement-based equivalent single layer (ESL) plate theories for laminates, this paper presents a generic and automatic method to extend a basis higher-order shear deformation theory (polynomial, trigonometric, hyperbolic, ...) to a multilayer $C^0_z$ higher-order shear deformation theory. The key idea is to enhance the description of the cross-sectional warping: the odd high-order $C^1_z$ function of the basis model is replaced by one odd and one even high-order function and including the characteristic zig-zag behaviour by means of piecewise linear functions. In order to account for arbitrary lamination schemes, four such piecewise continuous functions are considered. The coefficients of these four warping functions are determined in such a manner that the interlaminar continuity as well as the homogeneity conditions at the plate's top and bottom surfaces are {\em a priori} exactly verified by the transverse shear stress field. These $C_z^0$ ESL models all have the same number of DOF as the original basis HSDT. Numerical assessments are presented by referring to a strong-form Navier-type solution for laminates with arbitrary stacking sequences as well for a sandwich plate. In all practically relevant configurations for which laminated plate models are usually applied, the results obtained in terms of deflection, fundamental frequency and local stress response show that the proposed zig-zag models give better results than the basis models they are issued from

Apuntes sobre conservación material de sitios de memoria emplazados en ex CCDTyE de la Ciudad de Buenos Aires: desafíos y tensiones

Los sitios de memoria emplazados en ex centros clandestinos de detención, tortura y exterminio (ex CCDTyE) constituyen a la vez mojones de la memoria colectiva, sitios de experiencia, lugares de recuerdo y elaboración personal y documentos que pueden aportar información a la justicia y a la historia. Distintos actores intervienen en ellos articulando sus diversos valores, funciones y públicos. En este artículo me propongo dar cuenta de las formas en que los saberes y prácticas de la conservación se ponen en juego en los ex CCDTyE de la Ciudad de Buenos Aires. Intentaré establecer qué le aporta esta disciplina a los sitios de memoria e, inversamente, cómo la práctica en estos lugares representa nuevos desafíos y formas de trabajar para la misma. Para esto, a partir del análisis de una serie de entrevistas, voy a dar cuenta de cuáles son las prácticas de estos actores y los criterios que adoptan ante algunos de los desafíos y tensiones a los que se enfrentan en su trabajo sobre estos objetos patrimoniales singulares.The sites of memory located in former clandestine centers of detention, torture and extermination are, at the same time, milestones of collective memory, sites of experience, places of remembrance and personal elaboration of trauma and documents that can provide information for justice and history. Different actors participate in these sites of memory articulating their diverse values, functions and publics. In this article, I intend to account for the ways in which the concepts and practice of the discipline of conservation play a part in the former clandestine centers of detention found in Ciudad de Buenos Aires. My aim is to establish what the role of this discipline is in these sites of memory and, conversely, how the practice in these places represents new challenges and methodologies for conservation. Based on the analysis of interviews, I will account for these actors’ practices and the criteria they adopt when facing the challenges and tensions that come forward when they work on this singular heritage.Fil: D'ottavio, Adriana Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Sociales. Instituto de Desarrollo Económico y Social. Centro de Investigaciones Sociales; Argentina. Universidad Nacional de Tres de Febrero; Argentin

Benchmark d'un modele pour sandwiches et multicouches, de type layer-wise en contrainte

International audienceDans cet article, le comportement des composites stratifiés est étudié en utilisant des développements d'ordres élevés ou de type layer-wise. Un modèle Layer-wise (et l'élément fini à huit noeuds qui lui est associé) a été développé en premier lieu pour l'analyse spécifique des contraintes entre les couches pour des problèmes de bords libres [8][9] ou bien pour l'étude des liaisons entre les couches. Ce modèle est au coeur des comparaisons de cet article. Il est fondé sur un modèle de type layer-wise qui considère le stratifié comme une superposition de plaques de Reisner couplées les unes aux autres par des efforts d'interfaces. Cet élément a 5n degrés de liberté par noeud (n étant le nombre de couches) et donne une prédiction des contraintes d'interface. Les articles précédents se concentraient sur la précision de l'estimation de ces contraintes d'interface. Le modèle permet aussi de calculer les déplacements et les déflexions ainsi que d'extraire les contraintes dans l'épaisseur avec ou sans post-traitement. Dans cet article, la précision et la validité du calcul des déplacements et des contraintes ont été établies à partir d'un nombre important de tests classiques de benchmark en flexion pour les composites et les plaques en sandwich. Le but de cette étude est aussi de mieux positionner et de promouvoir cette approche en contraintes issue des travaux de Pagano peu utilisés et mal référencés

Influence of the number of trials and the exercise to rest ratio in repeated sprint ability, with changes of direction and orientation

The purpose of this investigation was to determine if there were different trends in physical fatigue observed in 3 different sets, of 7 trials each, in repeated sprint training, performed in 3 different modes: straight sprinting over 30 m, shuttle sprinting over 15 + 15 m, and sprinting over 30 m with changes of direction. Recovery time among trials in the sets was administered according to the 1:5 exercise to rest ratio. The sets were performed on 3 different days, with at least 48 hours between each set. The study involved 17 trained male soccer players (height, 177.33 +/- 6.21 cm; body mass, 71.63 +/- 9.58 kg; body mass index, 23 +/- 2.39 kg<bold>m(</bold>-2); age, 21.94 +/- 3.58 years). To compare the different values of the time recorded, an index of fatigue was used. Significant differences among trials within each set (repeated measures analysis of variance; p < 0.05) and between the sets (factorial analysis of variance; p < 0.001) were found. Significant correlations between each test and countermovement jump and stiffness values recorded pre exercise were found (p < 0.05). Significant differences between countermovement jump and stiffness values recorded pre and post exercise were also found (p < 0.05). This study suggests that training sessions aimed at increasing the capacity of repeated sprint ability in nonlinear and multidirectional sprints (shuttle and change of direction), which might imply a different number of trials within the set or different exercise to rest ratios from the ones usually adopted for straight sprinting, to induce similar trends of fatigue. As practical applications, the estimated numbers of necessary trials in the different sets and the possible exercise to rest ratios, resulting from mathematical modeling, are provided for each investigated sprinting mode

Translating human drug use patterns into rat models: exploring interindividual differences via refined drug self-administration procedures

Drug users instrumentalize the drug dosing-timing relationship (i.e. preferred drug dose in the preferred time) to produce their desired effects (i.e. euphoria, withdrawal avoidance, etc.). This is achieved by harnessing drug type, dosage, route, and frequency of drug taking. Yet, preclinical addiction research often employs self-administration and choice procedures based on discrete, as opposed to continuous dimension strategies, characterized by pre-selected experimenter-imposed unit-doses spaced by timeouts. This approach imposes constraints on the dose-time relationship voluntary harnessed by individuals with drug-addiction in real-world. This dissertation is devoted to the refinement of animal models of drug addiction. The considerations for the refinements stem from a detailed analysis of naturalistic patterns of drug taking in humans and are based on a strict pharmacokinetics and pharmacodynamics analysis of the drugs being investigated. The ambition is to guide preclinical researchers toward the self-administration procedure for neuropharmacological studies, tailored to the specific drug being investigated and is largely motivated by the limited advancements in available treatment options stemming from preclinical insights

A remark on a paper by Bhattacharya and Leonetti

summary:We prove higher integrability for the gradient of bounded minimizers of some variational integrals with anisotropic growth

Paracelsus and the Medicine of the Renaissance in the Cinema

The brief, eventful and fruitful life of Paracelsus, a 16th century doctor, motivated a German tribute film in 1943, approximately 400 years after his death that rescued a fragment of his existence. The filming and premiere took place during the Second World War and was rigorously controlled by the Nazis. This produced certain controversies, still in force, related to its director. This paper intends to portrait both facts.La breve, azarosa y fructífera vida de Paracelso, médico del siglo XVI, motivó en 1943, aproximadamente 400 años después de su muerte, a un film homenaje alemán que rescató un fragmento de su existencia. El rodaje y estreno se realizó en plena segunda guerra mundial y fue controlado rigurosamente por el nazismo. Esto produjo determinadas polémicas, aún vigentes, relacionadas con su director. Este trabajo intenta dar cuenta de ambos hechos