Further properties of the Bergman spaces of slice regular functions

In this paper we continue the study of Bergman theory for the class of slice regular functions. In the slice regular setting there are two possibilities to introduce the Bergman spaces, that are called of the first and of the second kind. In this paper we mainly consider the Bergman theory of the second kind, by providing an explicit description of the Bergman kernel in the case of the unit ball and of the half space. In the case of the unit ball, we study the Bergman-Sce transform. We also show that the two Bergman theories can be compared only if suitable weights are taken into account. Finally, we use the Schwarz reflection principle to relate the Bergman kernel with its values on a complex half plane.Comment: to appear in Advances in Geometr

Bully-victimization, depression, and school connectedness in early adolescent students

During early adolescence, schools play a significant role in the development of students. An issue that continues to be a serious concern for students, parents, teachers, and school officials in the U.S. and around the world is bullying. The primary purpose of this study was to examine school connectedness as a mediator between bully-victimization and depressive symptomatology in early adolescence. The secondary purpose of the study was to explore how gender and bullying classification groups (i.e., bully, victim, bully-victim, and non-involved) may relate to levels of reported school connectedness. The current study found low school connectedness partially mediated the relationship between bully victimization and depressive symptoms. Results also showed non-involved youth reported higher levels of school connectedness compared to bullies, victims, and bully-victim. The present study sought to expand literature of bullying, depression, and school connectedness in early adolescence with the aim of informing prevention, intervention and policy initiatives

Algorithms for Del Pezzo Surfaces of Degree 5 (Construction, Parametrization)

It is well known that every Del Pezzo surface of degree 5 defined over k is parametrizable over k. In this paper we give an efficient construction for parametrizing, as well as algorithms for constructing examples in every isomorphism class and for deciding equivalence.Comment: 15 page

Effect of Metallic Waste Addition on the Physical and Mechanical Properties of Cement-Based Mortars

© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).This paper investigates the influence of the type and amount of recycled metallic waste on the physical and mechanical properties of cement-based mortars. The physical and mechanical properties of cement mortars, containing four different amounts of metallic waste (ranged 4 to 16% by cement weight), were evaluated by measuring the bulk density, total porosity, flexural and compressive resistance, and dynamic elastic modulus by ultrasonic tests. All the properties were measured on test specimens under two curing ages: 7 and 28 days. Additionally, the morphological properties and elemental composition of the cement and metallic waste were evaluated by using Scanning Electron Microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS), and X-ray fluorescence (XRF). Main results showed that the addition of metallic waste reduced the bulk density and increased the porosity of the cement-based mortars. Furthermore, it was observed that flexural and compressive strength proportionally increased with the metallic waste addition. Likewise, it was proven that elastic modulus, obtained by compressive and ultrasonic tests, increases with the metallic waste amount. Finally, based on a probability analysis, it was confirmed that the addition of metallic waste did not present a significant effect on the mechanical performance of the cement-based mortars.Peer reviewedFinal Published versio

Avances en Sistemas y Computación

Después de dos décadas de publicación masiva de contenidos digitales en la Web, ahora la comunidad científica se enfrenta al reto de aprovechar de forma fácil y eficiente toda la información valiosa disponible. Para ello entre otras estrategias se ha centralizado la producción académica en repositorios abiertos, los cuales representan la fuente de información de mejor calidad para el desarrollo de la educación y de la investigación científica pues en ellos se almacena todo tipo de documentos académicos sobre cualquier tema del conocimiento humano. En este trabajo se describe el software de licencia libre que permite la implementación de estos repositorios, haciendo un análisis comparativo de las herramientas de desarrollo disponibles, posteriormente se describe la situación actual de los repositorios abiertos en el mundo y finalmente se describe la situación de estos repositorios en Méxic