Variable stars in the VVV globular clusters

Indexación: Scopus.The VVV survey observed some of the most crowded and most obscured regions in the inner Milky Way during the last years. A significant sample of the less known globular clusters in our galaxy lie there. Combining the high-resolution, wide-field, near infrared capabilities of the survey camera, the use of 5 different filters, and multi-epoch observations, we are able to overcome many of the previous challenges that prevented a proper study of these objects. Particularly, the identification of the RR Lyrae stars in these globular clusters is proving to be a fundamental tool to establish accurately their distances and reddenings, and to infer information about the Oosterhoff dichotomy that Galactic globular clusters seem to follow. © The Authors, published by EDP Sciences, 2017.https://www.epj-conferences.org/articles/epjconf/pdf/2017/21/epjconf_puls2017_01022.pd

Validation and Adaptation of the Prosocial and Antisocial Behavior in Sport Scale to the Spanish context of Physical Education

Physical education (PE), by its own characteristics, is a subject where social communication is especially promoted. However, it is necessary to have tools that evaluate the social behaviour of students during PE classes. For this reason, we propose to validate and adapt the Prosocial and Antisocial Behavior in Sport Scale to the Spanish context of PE classes. The study involved 1081 students aged 12 to 18 (M = 14.83; SD = 1.27). The psychometric properties of the Prosocial Behavior Scale were analyzed through several statistical analyses. The results of the confirmatory factorial analysis and the exploratory factorial analysis supported the internal structure of the questionnaire. In addition, the scale was invariant to gender. Cronbach’s alpha values were higher than 0.70 in the factors and sub-factors, finally showing adequate levels of temporal stability. Taking into account the results achieved in the present study, PE teachers have an effective tool to assess the social and antisocial behaviour of their students’ students during PE classes

An extended Agassi model: algebraic structure, phase diagram, and large size limit

The Agassi model is a schematic two-level model that involves pairing and monopole-monopole interactions. It is, therefore, an extension of the well known Lipkin-Meshkov-Glick (LMG) model. In this paper we review the algebraic formulation of an extension of the Agassi model as well as its bosonic realization through the Schwinger representation. Moreover, a mean-field approximation for the model is presented and its phase diagram discussed. Finally, a $1/j$ analysis, with $j$ proportional to the degeneracy of each level, is worked out to obtain the thermodynamic limit of the ground state energy and some order parameters from the exact Hamiltonian diagonalization for finite$-j$.Comment: Accepted in Physica Scripta. Focus on SSNET 201

Phase diagram of an extended Agassi model

Background: The Agassi model is an extension of the Lipkin-Meshkov-Glick model that incorporates the pairing interaction. It is a schematic model that describes the interplay between particle-hole and pair correlations. It was proposed in the 1960's by D. Agassi as a model to simulate the properties of the quadrupole plus pairing model. Purpose: The aim of this work is to extend a previous study by Davis and Heiss generalizing the Agassi model and analyze in detail the phase diagram of the model as well as the different regions with coexistence of several phases. Method: We solve the model Hamiltonian through the Hartree-Fock-Bogoliubov (HFB) approximation, introducing two variational parameters that play the role of order parameters. We also compare the HFB calculations with the exact ones. Results: We obtain the phase diagram of the model and classify the order of the different quantum phase transitions appearing in the diagram. The phase diagram presents broad regions where several phases, up to three, coexist. Moreover, there is also a line and a point where four and five phases are degenerated, respectively. Conclusions: The phase diagram of the extended Agassi model presents a rich variety of phases. Phase coexistence is present in extended areas of the parameter space. The model could be an important tool for benchmarking novel many-body approximations.Comment: Accepted for publication in PR

Precompact Fréchet topologies on Abelian groups

AbstractWe study precompact Fréchet topologies on countable Abelian groups. For every countable Abelian group G we introduce the notion of a γG-set and show that there is a precompact Fréchet non-metrizable topology on G if and only if there is an uncountable γG-set that separates points of G. We show that, assuming the existence of an uncountable γ-set, there is a non-metrizable precompact Fréchet topology on every countable Abelian group, and assuming p>ω1, there is a non-metrizable Fréchet topology on every countable group which admits a non-discrete topology at all. We further study the notion of a γG-set and show that the minimal size of a subset of the dual group G⁎ which is not a γG-set is the pseudointersection number p for any countable Abelian group G

Quantum Phase Transitions in the Interacting Boson Model: Integrability, level repulsion and level crossing

We study the quantum phase transition mechanisms that arise in the Interacting Boson Model. We show that the second-order nature of the phase transition from U(5) to O(6) may be attributed to quantum integrability, whereas all the first-order phase transitions of the model are due to level repulsion with one singular point of level crossing. We propose a model Hamiltonian with a true first-order phase transition for finite systems due to level crossings.Comment: Accepted in PR

Cognitive Fusion Mediates the Relationship between Dispositional Mindfulness and Negative Affects: A Study in a Sample of Spanish Children and Adolescent School Students

Nowadays, mindfulness-based interventions (MBI) have experienced a remarkable development of studies among childhood and adolescent interventions. For this reason, dispositional mindfulness (DM) measures for children and adolescents have been developed to determine the e ectiveness of MBI at this age stage. However, little is known about how key elements of DM (for example, cognitive de/fusion or experiential avoidance that both confirm psychological inflexibility) are involved in the mechanisms of the children and adolescents’ mental health outcomes. This research examined the mediating e ect of cognitive fusion between DM and anxiety and other negative emotional states in a sample of 318 Spanish primary-school students (aged between 8 and 16 years, M = 11.24, SD = 2.19, 50.8% males). Participants completed the AFQ-Y (Avoidance and Fusion Questionnaire for youth), which is a measure of psychological inflexibility that encompasses cognitive defusion and experiential avoidance; CAMM (DM for children and adolescents), PANAS-N (positive and negative a ect measure for children, Spanish version of PANASC), and STAIC (an anxiety measure for children). The study accomplished ethical standards. As MBI relevant literature has suggested, cognitive defusion was a significant mediator betweenDMand symptoms of both negative emotions and anxiety in children and adolescents. However, experiential avoidance did not show any significant mediating relationship. Probably, an improvement of the assessment of experiential avoidance is needed. MBI programs for children and adolescents may include more activities for reducing e ects of the cognitive defusion on their emotional distress

Conceptual design of the ITER fast-ion loss detector

et al.A conceptual design of a reciprocating fast-ion loss detector for ITER has been developed and is presented here. Fast-ion orbit simulations in a 3D magnetic equilibrium and up-to-date first wall have been carried out to revise the measurement requirements for the lost alpha monitor in ITER. In agreement with recent observations, the simulations presented here suggest that a pitch-angle resolution of ∼5° might be necessary to identify the loss mechanisms. Synthetic measurements including realistic lost alpha-particle as well as neutron and gamma fluxes predict scintillator signal-to-noise levels measurable with standard light acquisition systems with the detector aperture at ∼11 cm outside of the diagnostic first wall. At measurement position, heat load on detector head is comparable to that in present devices.This research was supported in part by the Spanish Ministry of Economy and Competitiveness (Grant Nos. RYC2011-09152, FIS2015-69362-P, and ENE2012- 31087) and the Marie Curie FP7 Integration Grant (No. PCIG11-GA2012-321455).Peer Reviewe

Productos de alfarería de Cerro Macareno, Sevilla : naturaleza y procedencia de las ánforas y otros objetos cerámicos. Siglos VIII al III a. J.C.

Son muchos los métodos empleados para el estudio de las arcillas y de los productos cerámicos, contribuyendo de distinta manera, aunque complementaria, en el conocimiento de la composición, procedencia de los materiales, tecnología empleada en su elaboración y en general en todos aquellos procesos que se pudieron seguir en la tibricación del objeto cerámico. Estos métodos pueden ser, bien destructivos, aunque utilizando cantidades muy pequeñas de muestra, o bien no destructivos, cada vez más empleados en la investigación moderna. En el estudio de los materiales cerámicos, bien sea el soporte, o bien sea la pintura que ha servido para decorarlo, se emplea el análisisq\límico tradicional cualitativo y cuantitativo. Para este último se emplea cada \leimás la técnica de la absorción atómica. Asimismo, se emplean los siguientes métodos de análisis por vía física: La espectroscopía de emisión en el ultravioleta, que permite obtener un espectro de emisión en el que la parte más frecuentemente utilizada se sitúa entre 200 y 400 nm (ultravioleta). La espectrometría de fluorescencia de rayos X es una técnica desde hace tiempo utilizada. El método tiene poca sensibilidad para elementos tales como el cobre, níquel, cinc o hierro, a causa del «ruido de fondo» que el mismo aparato emite. La microfluorescencia permite operar directamente sobre una capa de pintura y su análisis no es destructivo. La microsonda electrónica es una aplicación de los principios y de la técnica de la espectrografía de emisión de rayos X. Su poder separador es infinitamente superior al del mejor instrumento óptico. La activación por neutrones, que precisa de una fuente generadora de estas radiaciones (pila atómica), es, por tanto, de muy difícil empleo. En España se utiliza la pila atómica de la Junta de Energía Nuclear. Este análisis permite determinar los elementos mayores, menores y trazas existentes en los objetos cerámicos y en los pigmentos. Es de un gran interés para conocer la procedencia de los materiales empleados, detectando el posible o posibles yacimientos de las arcillas utilizadas. La difracción de rayos X determina la estructura cristalina de los elementos y compuestos químicos ya sean orgánicos o inorgánicos, si bien la técnica no es válida para los compuestos amorfos. Para el estudio de aquellos materiales en los que la pintura se encuentre unida al soporte mediante lacas, gomas o barnices se emplean métodos de absorción en el infrarrojo, así como la cromatografía en fase gaseosa. Los métodos seguidos que se enumeran en el siguiente apartado nos han permitido identificar la procedencia y naturaleza de las arcillas utilizadas en los objetos cerámicos objeto de este estudio.Peer reviewe

Materias primas y datos tecnológicos de piezas cerámicas antiguas del yacimiento arqueológico de Cerro Macareno (Sevilla)

14 páginas, 5 figuras, 7 tablas, 7 referencias.[EN]: A study of twenty eight fragments of amphoras from the archaeological bed of Cerro Macareno (Sevilla) has been done by chemical, physicochemical, X-ray diffraction and thermal methods, in order to establish the nature and provenance of the raw materials and the technological aspects of their fabrication. All the data lead to the conclusion that four of the pieces were probably imported from the Palestine-Phoenicie; the rest were made out of raw materials from the surrounding areas of Cerro Macareno. Most of the pieces were fired below 700°C, only four of them at about 700-750°C, and the other seven, probably from 800-850°C.[ES]: Se estudian la composición química y mineralógica, contenido en determinados elementos escasos, materias primas y temperaturas probables de cocción empleadas en la fabricación de un conjunto de 25 fragmentos de ánforas del yacimiento arqueológico de Cerro Macareno (Sevilla). Los métodos empleados fueron análisis químico, difracción de rayos-X, A.T.D., análisis por activación neutrónica y pruebas de cocción intermitente por calentamiento de cien en cien grados, desde 400° a 1.100° C seguido en cada caso de estudios por difracción de rayos-X y de observación de los cambios de color y aspecto de los cortes de las piezas. De todo ello se concluye que cuatro de las piezas estudiadas son de origen importado (Palesti-na-Fenicia), estando fabricadas las restantes con materiales procedentes de los aluviones del Guadalquivir, en las inmediaciones del Cerro Macareno. Del total de las piezas, 17 se cocieron probablemente a temperaturas inferiores a 700°C, cuatro a 700-750° C y siete a 800-850°C.Peer reviewe