Maximal slicings in spherical symmetry: local existence and construction

We show that any spherically symmetric spacetime locally admits a maximal spacelike slicing and we give a procedure allowing its construction. The construction procedure that we have designed is based on purely geometrical arguments and, in practice, leads to solve a decoupled system of first order quasi-linear partial differential equations. We have explicitly built up maximal foliations in Minkowski and Friedmann spacetimes. Our approach admits further generalizations and efficient computational implementation. As by product, we suggest some applications of our work in the task of calibrating Numerical Relativity complex codes, usually written in Cartesian coordinates.Comment: 25 pages, 6 figure

La interacción y la regulación de los procesos de enseñanza-aprendizaje en la clase de ciencias : análisis de una experiencia

Después de muchos años de investigaciones para intentar desvelar los mecanismos que se ponen en marcha cuando se está aprendiendo, es un hecho reconocido que el proceso de enseñanza-aprendizaje escolar constituye, fundamentalmente, una situación de comunicación y un lugar de interacción donde desarrollar competencias cognitivas, sociales, emocionales y aprender autónomamente. El aprendizaje no es un proceso lineal y exclusivamente individual, por ello es absolutamente necesario analizar cómo los alumnos construyen socialmente el conocimiento para facilitar y promover ese proceso. En este artículo se analizan las interacciones que favorecen la regulación y la autorregulación de los aprendizajes y el progreso en la construcción de significados en ciencias. Partiendo de una experiencia global de introducción de la modalidad de aprendizaje cooperativo en los cursos del primer ciclo de la enseñanza secundaria obligatoria (ESO) de un centro escolar, se analizan datos correspondientes a sesiones de ciencias naturales impartidas en un curso de 2º de ESO con el objetivo de descubrir aspectos clave de la intervención docente, de conocer cómo se negocia el significado por parte de los participantes y qué estrategias de regulación utilizan cuando colaboran. Paralelamente se analiza la comprensión de los contenidos conceptuales y la elaboración de informes de experiencias hipotético-deductivas.We intend to analyze interactions that help regulation and self-regulation of learning and improvement of meaning construction in science. We analyze data from natural sciences lessons in a Secondary School to find key aspects of teaching purpose, to know how the meaning negotiation works, how pupils organise themselves and which regulation strategies develop when they cooperate. Simultaneously understanding of concepts and elaboration of reports about hypothetic deductive experiences are analysed

A Spatially Correlated Model with Generalized Autoregressive Conditionally Heteroskedastic Structure for Counts of Crimes

Crime is a negative phenomenon that affects the daily life of the population and its development. When modeling crime data, assumptions on either the spatial or the temporal relationship between observations are necessary if any statistical analysis is to be performed. In this paper, we structure space–time dependency for count data by considering a stochastic difference equation for the intensity of the space–time process rather than placing structure on a latent space–time process, as Cox processes would do. We introduce a class of spatially correlated self-exciting spatio-temporal models for count data that capture both dependence due to self-excitation, as well as dependence in an underlying spatial process. We follow the principles in Clark and Dixon (2021) but considering a generalized additive structure on spatio-temporal varying covariates. A Bayesian framework is proposed for inference of model parameters. We analyze three distinct crime datasets in the city of Riobamba (Ecuador). Our model fits the data well and provides better predictions than other alternatives.MCIU/AEI/ERDF, UE PGC2018-098860-B-I00ERDF Operational Programme 2014-2020 A-FQM-345-UGR18Economy and Knowledge Council of the Regional Government of Andalusia, Spain MCIN/AEI CEX2020-001105-MSpanish Government PID2019-107392RB-I00/AEI/10.13039/501100011033University Jaume I, Spain UJI-B2018-0

Dynamical spacetimes and gravitational radiation in a Fully Constrained Formulation

This contribution summarizes the recent work carried out to analyze the behavior of the hyperbolic sector of the Fully Constrained Formulation (FCF) derived in Bonazzola et al. 2004. The numerical experiments presented here allows one to be confident in the performances of the upgraded version of CoCoNuT's code by replacing the Conformally Flat Condition (CFC) approximation of the Einstein equations by the FCF.Comment: 4 pages, 7 figures. Accepted for publication in Journal of Physics: Conference Series, Proceedings of the 8th Edoardo Amaldi Conference on Gravitational Wave

On the convexity of Relativistic Ideal Magnetohydrodynamics

We analyze the influence of the magnetic field in the convexity properties of the relativistic magnetohydrodynamics system of equations. To this purpose we use the approach of Lax, based on the analysis of the linearly degenerate/genuinely non-linear nature of the characteristic fields. Degenerate and non-degenerate states are discussed separately and the non-relativistic, unmagnetized limits are properly recovered. The characteristic fields corresponding to the material and Alfv\'en waves are linearly degenerate and, then, not affected by the convexity issue. The analysis of the characteristic fields associated with the magnetosonic waves reveals, however, a dependence of the convexity condition on the magnetic field. The result is expressed in the form of a generalized fundamental derivative written as the sum of two terms. The first one is the generalized fundamental derivative in the case of purely hydrodynamical (relativistic) flow. The second one contains the effects of the magnetic field. The analysis of this term shows that it is always positive leading to the remarkable result that the presence of a magnetic field in the fluid reduces the domain of thermodynamical states for which the EOS is non-convex.Comment: 14 pages. Submitted to Classical and Quantum Gravit

Tirso de Molina, Amar por razón de estado

El autor dedica la primera parte de su estudio a circunscribir la fecha probable de composición de la obra. Una primera aproximación se basa en datos objetivos sacados de los paratextos de Cigarrales y de la edición príncipe, o sea la Primera Parte en Sevilla en 1627, elementos estudiados en su tiempo por la crítica (Kennedy, Paterson, Moll) y que siguen siendo tema de debate. Otros aspectos formales y estilísticos sacados a colación por otros estudiosos (Blanca de los Ríos) le parecen, con r..

Polimorfismo del gen del transportador de serotonina (5-HTT) y trastorno de depresión mayor en pacientes en bogotá, Colombia

Introduction: The 5-HTT short allele has been controversially associated with an increased risk of major depressive disorder. Objective: To determine the association of 5-HTT short allele with major depression in Bogotá, Colombia. Materials and methods: We carried out a study of cases (n=68) matched 1:1 with controls by gender and age (±5 years). Major depression was diagnosed using the Mini-International Neuropsychiatric Interview, and 5-HTT polymorphism using PCR. Results: Females were predominant (82.4%). The S (short) allele predominated in cases compared with controls (S: 72.1% vs. 63.2; L (long): 27.9% vs. 36.8%), and the SL genotype was more frequent in cases (SL: 45.6% vs. 36.8%; LL: 27.9% vs. 36.8%; SS: 26.5% vs. 26.5%), although not significantly. There were significant differences in those under age 37, with a predominance of the S allele in cases (p=0.038; OR=2.75; 95% CI: 0.88-8.64). Multivariate analysis, adjusted for comorbid anxiety disorders, showed a significant association of major depression with the SL genotype (p=0.049; OR=3.20; 95% CI: 1.00-10.23); the S allele was close to statistical significance (p=0.063; OR=2.94; 95% CI: 0.94-9.13), and it was statistically significant in cases under 37 years of age (p=0.026; OR=10.79; 95% CI: 1.32-80.36). Conclusions: The SL genotype was associated with major depressive disorder in patients of all ages. The S allele was significantly associated with major depressive disorder in patients under age 37, adjusted for comorbid anxiety disorders

Does virtual consultation between primary and specialised care improve healthcare quality? A scoping review of healthcare quality domains assessment

Virtual consultation has been proposed as a promising tool to improve the coordination and quality of healthcare between primary and specialised care. However, despite its potential facilitators, the evidence on the usefulness of virtual consultation for improving healthcare quality domains is fragmented and unclear. This scoping review aims to assess the impact of virtual consultation on different healthcare quality domains.Material and methodsWe conducted a scoping review with a rigorous search strategy on PubMed, EMBASE and Cochrane Library databases. The inclusion criteria were original articles, reviews, meta-analyses or letters to the editor, published between 1 January 2017 and 24 June 2022, and available in English, Spanish or French. For each of the articles selected, we identified the addressed healthcare quality domains, their facilitators and barriers, areas of improvement and data gaps. We have adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Review reporting standards.Results1284 manuscripts were retrieved. Finally, 235 papers were included in this review, most of which were original, descriptive studies. The most evaluated quality domain was effectiveness (223 articles). Safety and patient-centred care were the least evaluated. Simultaneous assessment of more than one domain was observed in 117 papers, being effectiveness and timeliness the most frequent combination. Our analysis revealed that virtual consultation is in development and underused. This tool has the potential to improve access to specialised care and enhance coordination between professionals.ConclusionsVirtual consultation has the potential to provide effective, efficient, equitable and timely attention. However, its contribution to safety and patient-centered care needs further evaluation. Our review emphasises the need for more rigorous research and standardised quality assessment criteria to obtain robust evidence on the usefulness of virtual consultation for improving healthcare quality domains