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ITER Collective Thomson Scattering (CTS) diagnostic system is designed to analyze the alpha particles resulting from Deuterium-Tritium fusion reactions. It consists of one launcher and nine receiver transmission lines. The launcher line transports the high-power microwave emission of 1.2 MW from the gyrotron source to the front-end, while the receiver lines transport the collected microwave emission from the front-end and distribute it to the instrumentation in the Diagnostic Building. Due to the high power transported in the launcher line, it has to be water-cooled to minimize the thermal expansion resulting from the heating caused by the power losses. Therefore, this work primarily focuses on establishing the cooling system parameters for the launcher TL to ensure efficient dissipation of the ohmic losses, while meeting the ITER cooling requirements. Once the parameters of the water cooling system are defined, a thermo-mechanical analysis of the most critical components is performed to assess their temperature distribution and deformations. [ABSTRACT FROM AUTHOR]

The computational modelling of the heart motion within a cardiac cycle is an extremely challenging problem due to (a) the complex multi-scale interaction that takes place between the electrophysiology and electrochemistry at cellular level and the macro-scale response of the heart muscle, and (b) the large deformations and the strongly anisotropic and quasi-incompressible behaviour of the myocardium. These pose an extreme challenge to the scalability of electro-mechanical solvers due to the size and conditioning of the system of equations required to obtain accurate solutions, both in terms of wall deformation and transmembrane potential propagation. In the search towards an efficient modelling of electro-activation, this paper presents a coupled electromechanical computational framework whereby, first, we explore the use of an efficient stabilised low order tetrahedral Finite Element methodology and compare it against a very accurate super enhanced mixed formulation previously introduced by the authors in Garcia-Blanco et al. (2019) and, second, we exploit the use of tailor-made staggered and staggered linearised solvers in order to assess their feasibility against a fully monolithic approach. Through a comprehensive set of examples, culminating in a realistic ventricular geometry, we aim to put forward some suggestions regarding the level of discretisation and coupling required to ensure sufficiently reliable results yet with an affordable computational time. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a novel computational framework for the numerical simulation of the electromechanical response of the myocardium during the cardiac cycle. The paper presents the following main novelties. (1) Two new mixed formulations, tailor-made for active stress and active strain coupling approaches, have been developed and used in conjunction with two different ionic models, namely Bueno-Orovio et al. (2008) and Ten Tusscher et al. (2004). Taking as a reference the mixed formulations introduced by Bonet et al. (2015) in the context of nonlinear elasticity, the proposed formulations include as unknown fields the geometry and the transmembrane potential (and possibly a Lagrange multiplier enforcing weakly the incompressibility constraint) as well as the deformation gradient tensor, its cofactor, its determinant, the gradient of the transmembrane potential and their respective work conjugates. The Finite Element implementation of these formulations is shown in this paper, where a static condensation procedure is presented in order to yield an extremely competitive computational approach. (2) A comprehensive and rigorous study of different ionic models (i.e Bueno-Orovio and Ten Tusscher) and electromechanical activation couplings (i.e active strain and active stress) has been carried out. (3) An analytical and numerical analysis of the possible loss of ellipticity and polyconvexity of one of the most widely used constitutive models in the context of cardiac mechanics is carried out in this paper, putting forward possible polyconvexifications of the existing model. (4) In addition, an invariant representation of Guccione's constitutive model is proposed. Finally, a series of numerical examples are included in order to demonstrate the applicability and robustness of the proposed formulations. [ABSTRACT FROM AUTHOR]

The objective of this article is to estimate the relative weight of socioeconomic, academic and cultural factors in the learning disadvantages of indigenous elementary students in Mexico. To this end, hierarchical linear and Oaxaca-Blinder models were specified to analyze and decompose the learning gap between indigenous and non-indigenous students, on the basis of microdata from the National Plan for Learning Assessment (PLANEA) 2015. The main results are 1) beyond individual differences, many of these differences are explained by the percentage of indigenous students in schools (the compositional effect); 2) these differences are greatly reduced when socioeconomic and academic factors are controlled for (especially the former); and 3) although socioeconomic factors account for most of the gap, students' academic trajectories and the characteristics of the schools they attend take on greater relevance in explaining differences in mathematics and the specific disadvantage experienced by students who learned an indigenous language first. [ABSTRACT FROM AUTHOR]

In this article, I analyze a set of hypotheses derived from Bourdieu's and Passeron's theory of reproduction, to explain the inequalities of learning in Spanish at the elementary level in Mexico. The hypotheses refer to the role of cultural capital, educational resources, students' academic aspirations, and the family's educational practices. My starting point is the general thesis that certain specific characteristics of Mexico's society and educational system constitute a scenario that is less favorable for the theory of reproduction, and more favorable for a situation I refer to as "limited educational mobility". The study results support this thesis; they emphasize, however, the persistence of still unexplained structural effects on learning. [ABSTRACT FROM AUTHOR]

El artículo discurre sobre la calidad de la educación básica en México. Los autores comentan sobre los desafíos asociados con la falta de mejora de la calidad de educación, incluyendo factores económicos, sociales y políticos. También se considera el impacto de la violencia, la pobreza y la desigualdad en la sociedad mexicana.

Abstract: Although the word té (tea) in Spanish is derived from the Chinese tscha and refers to the oriental plant Camellia sinensis, it is popularly used throughout Spain to refer to at least 70 different plant species. These are usually collected in the countryside, boiled dry or fresh, and drunk after meals. The drinking of té is a social habit that encourages conversation in a relaxed atmosphere. Tés are also commonly used as digestifs and stomachics, and in some cases as laxatives, antidiarrhoeics, and to reduce the blood pressure. They are not used as stimulants. It appears that the habit of drinking Camellia sinensis afforded the cognitive context for drinking other infusions with no specific medicinal purpose. Some té species are very common in Spain (and their use is quite extended), others are endemic, and others still are allochthonous that now live in the wild. The majority of these species belong to the families Asteraceae and Lamiaceae. The most important and widely distributed are Jasonia glutinosa, Sideritis hyssopifolia, Lithospermum officinale, Chenopodium ambrosioides and Bidens aurea. Other remarkable but more locally used tés include Cruciata glabra (only in the Pyrenees), Inula salicina and Mentha arvensis (in the Central Mountain Range of Madrid), and Potentilla caulescens (in Tarragona). [Copyright &y& Elsevier]

Se evalúa la fiabilidad de de varios modelos causales para la predicción de la inflación en Argentina de 1993 a 2006. Se explica que los modelos estudiados están basados en teorías de la inflación tales como un Valor en Riesgo (Value at Risk o VaR en inglés) monetario y la curva de Phillips. Se hace hincapié en modelos de "pooling" (combinaciones) de pronósticos diseñados para superar las dificultades que suponen para la predicción los cambios de régimen.