Escenas de lectura: naciones imaginadas y el romance de la historia en Hispanoamérica

Este artículo explora el papel de la cultura letrada, y de las novelas en particular, en la constitución de los imaginarios nacionales durante el siglo XIX en Hispanoamérica. Arguye que si bien las novelas de Lizardi empiezan el proceso, la dimensión his

Signos radiológicos y ecográficos asociados al síndrome de hiperadrenocorticismo en perros

Aunque el diagnostico de hiperadrenocorticalismo se confirma habitualmente por test endocrinos, radiologia y ecografia aportan datos en los pacientes que permiten realizar una valoracion clinica mas concreta. Este articulo revisa los cambios radiográficos y ecográficos que pueden aparecer en perros con hiperadrenocorticalismo

Equivalent norms in a banach function space and the subsequence property

[EN] Consider a finite measure space (Omega, Sigma, mu) and a Banach space X(mu) consisting of (equivalence classes of) real measurable functions defined on Omega such that f chi(A) is an element of X(mu) and parallel to f chi(A)parallel to <= parallel to f parallel to, for all f is an element of X(mu), A is an element of Sigma. We prove that if it satisfies the subsequence property, then it is an ideal of measurable functions and has an equivalent norm under which it is a Banach function space. As an application we characterize norms that are equivalent to a Banach function space norm.All the authors were supported by Ministerio de Ciencia, Innovacion y Universidades (Spain), Agencia Estatal de Investigaciones, and FEDER. J.M. Calabuig and M. Fernandez-Unzueta under project MTM2014-53009-P. F. Galaz-Fontes under project MTM2009-14483-C02-01 and E. A. Sanchez Perez under project MTM2016-77054-C2-1-P. M. FernandezUnzueta was also supported by CONACYT 284110.Calabuig, JM.; Fernández-Unzueta, M.; Galaz-Fontes, F.; Sánchez Pérez, EA. (2019). Equivalent norms in a banach function space and the subsequence property. Journal of the Korean Mathematical Society. 56(5):1387-1401. https://doi.org/10.4134/JKMS.j180682S1387140156

Un simulador para asistir en la enseñanza del teorema de Bayes

[EN] Teaching some basic concepts in Statistics greatly benefits from individual practice with immediate feedback. In order to provide such practice to a large number of students we have writen a simulator described below, first of a planned series of teaching aids. It is designed to assist in the teaching of Bayesian concepts and, in particular, to instill in students the idea that probabilities can change as evidence accumulates.[ES] La enseñanza de algunos conceptos básicos de Estadística se benecia deprácticas individuales con realimentacion inmediata. Para poder llevarlasa cabo con un gran número de alumnos hemos escrito un simulador que sedescribe a continuacion, primero de una serie que planeamos. Su propósitoes incrementar la familiaridad de los estudiantes con conceptos básicos dela estadística bayesiana; en particular, familiarizarles con la idea de quelas probabilidades cambian a medida que la informacion aumenta.Este proyecto ha contado con una subvención del SAE de la Universidad del País Vasco (UPVEHU), en la convocatoria 2015-2017 de Programas de Innovación Educativa.Bárcena, M.; Garín, A.; Martín, A.; Tusell, F.; Unzueta, A. (2017). Un simulador para asistir en la enseñanza del teorema de Bayes. En In-Red 2017. III Congreso Nacional de innovación educativa y de docencia en red. Editorial Universitat Politècnica de València. 15-23. https://doi.org/10.4995/INRED2017.2017.6725OCS152

Observation of a charge delocalization from Se vacancies in Bi2Se3: A positron annihilation study of native defects

[EN] By means of positron annihilation lifetime spectroscopy, we have investigated the native defects present in Bi2Se3, which belongs to the family of topological insulators. We experimentally demonstrate that selenium vacancy defects (VSe1) are present in Bi2Se3 as-grown samples, and that their charge is delocalized as temperature increases. At least from 100 K up to room temperature both V0Se1and V+Se1 charge states coexist. The observed charge delocalization determines the contribution of VSe1defects to the n-type conductivity of Bi2Se3. These findings are supported by theoretical calculations, which show that vacancies of nonequivalent Se1 and Se2 selenium atoms are clearly differentiated by positron annihilation lifetime spectroscopy, enabling us to directly detect and quantify the most favorable type of selenium vacancy. In addition to open-volume defects, experimental data indicate the presence of defects that act as shallow traps, suggesting that more than one type of native defects coexist in Bi2Se3. As will be discussed, the presence of a dislocation density around 1010cm−2 could be the source of the detected shallow traps. Understanding the one-dimensional defects and the origin of the charge delocalization that leads Bi2Se3 to be an n-type semiconductor will help in the development of high-quality topological insulators based on this material.This work is supported for the Basque Government Grant IT-443-10 and partially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under the project TEC2014-60173 and by the Generalitat Valenciana under the projects Prometeo II 2015/004 and ISIC/2012/008. I. Unzueta also wants to acknowledge financial support from the Basque Government Grant PRE-2014-214. V. Marín-Borrás thanks the University of Valencia for its pre-doctoral fellowships. Finally we would also like to thank BCMaterials for its economic support

Identification of Ni-vacancy defect in Ni-Mn-Z (Z = Ga, Sn, In): An experimental and DFT positron annihilation study

[EN] By means of experimental positron-annihilation-lifetime measurements and theoretical density functional theory (DFT) positron-lifetime calculations, vacancy-type defects in Ni50Mn50−xSnx (x=25, 20,15,13,10) and Ni50Mn50−xInx (x=25,20,16,13) systems are systematically studied. The study is extended to Ni-Mn-Ga systems as well. Experimental results are complemented with electron-positron DFT calculations carried out within the local density approximation and generalized gradient approximation, where five different parametrizations accounting for the γ(r) enhancement factor are analyzed. Theoretical results indicate that the Boronski-Nieminen parametrization of γ(r) is the one that best predicts the experimental results, which ultimately enables us to identify VNi as the vacancy present in the studied samples. The characteristic positron lifetime related to VNi ranges between 181 and 191 ps in Ni-Mn-Sn/In systems. Positron-annihilation-lifetime spectroscopy results in these two systems delimit the lower bound of the achievable vacancy concentration, which is much larger compared with the reported values in Ni-Mn-Ga systems. The present work, along with setting the basis for positron simulations in Ni-Mn based Heusler alloys, delimits the effect that the variation of vacancies has in the martensitic transformation in Ni-Mn-Sn systemsThis work is supported by the Basque Government and Spanish Ministry of Economy and Competitiveness under grants IT-1005-16, IT-756-13 and MAT2015-65165-C2-R (MINECO/FEDER). I. Unzueta also wants to acknowledge the Basque Government Grant PRE-2014-214

Vacancies mediated ordering in Ni-Mn-Ga shape memory alloys

[EN] Vacancy mediated diffusion is the main atomic mechanism that controls the ordering of substitutional alloys. In particular, in Ni-Mn-Ga shape memory alloys vacancies control the evolution of the L21 atomic order degree and consequently most of the order-dependent properties of the martensitic transformation. This work adapts a general phenomenological model to quantify the evolution of the vacancy concentration during the ordering process for three different Ni-Mn-Ga alloys. The results show that out of equilibrium vacancies are responsible of the ordering process, fixing the set of parameters governing it. The present work shows the suitability of the model to determine the vacancy dynamics throughout any process in which they intervene.This research was funded by Projects RTI2018-094683-B-C5 (4,5) (MCIU/AEI/FEDER, UE) and Basque Government Grant IT-1005-16

Low temperature magnetic properties of a Ni50Mn34In16 ball-milled metamagnetic shape memory alloy

[EN] The effect of the atomic disorder induced by ball-milling on the structure and the magnetic properties has been analyzed in a Ni50Mn34In16 metamagnetic shape memory alloy. The as-milled samples displayed an amorphous structure which crystallizes to a disordered B2 structure on annealing. On further annealing, several recovery processes leading to the austenitic L21 structure and the subsequent martensitic transformation are observed. As a result of the recovery processes, the magnetic order drastically varies concurrent with the long-range atomic order. In particular, the magnetism evolves from a frustrated magnetic state compatible with a canonical spin-glass, observed in the amorphous structure, to the well-developed ferromagnetic state.This work has been carried out with the financial support of the Spanish “Ministerio de Economía y Competitividad” and FEDER funding, projects no. MAT2012-37923 and MAT2015-65165-C2-R. I. Unzueta acknowledges financial support from the Basque Government Grant nos. IT-443-10 and PRE_2014_214