592 research outputs found
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..
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
Quien tiene un hermano, tiene un tesoro: Análisis de las relaciones fraternales cuando un hermano tiene trastorno del espectro autista
Treball Final de Grau en Psicologia. Codi: PS1048. Curs acadèmic: 2016/2017Las relaciones entre hermanos suponen el primer contacto con el mundo social y varían en
función de distintas características, como el orden de nacimiento, la edad, y la existencia de una
diversidad funcional en la fratría. Por esto, el presente estudio busca analizar estas influencias
cuando uno de los hermanos tiene Trastorno del Espectro Autista (TEA). La muestra estuvo
formada por 20 madres (11 en el grupo TEA y 9 en el grupo control), y 4 padres (2 en cada
grupo), y las edades de sus hijos estaban comprendidas entre los 2 y 21 años. Se utilizó el
cuestionario Sibling Inventory of Behaviour (SIB) para medir la relación, además de una
subescala añadida que concretaba aspectos del TEA. En el estudio cuantitativo, los datos
señalaron que los hermanos del grupo TEA puntuaron más alto en Agresividad que el grupo
control. Además, en función de la edad, los hermanos del grupo TEA presentaron niveles más
altos de Evitación con respecto al grupo control cuando el hermano con TEA era el mayor. En el
análisis cualitativo de dos pares de gemelos del grupo TEA, se observó una peor relación a nivel
general de la pareja de gemelos pequeños. Estos resultados ponen de manifiesto la necesidad de
comprensión del TEA por parte del hermano neurotípico.Sibling relationships serve as a first contact with the social world and they change depending
on some characteristics as bith order, age, and the existence of functional diversity in one of the
children. Due to this reason, the main objective of this study is to analyse that influences when
one of the siblings has Autism Spectrum Disorder (ASD). 20 mothers (11 from ASD group and
9 from control group) and 4 parents (2 for both groups) participated in the study, and their
children ages ranged between 2 and 21 years. Sibling Inventory of Behaviour (SIB) was used to
measure the sibling relationship, and it was also added a subscale with ASD characteristics.
Quantitative analysis showed that siblings of ASD children had greater Aggression scores than
control group. Furthermore, regarding the age, ASD siblings had greater Avoidance scores
compared to control group when ASD child was the older sibling. Qualitative analysis between
twin siblings of ASD group showed that younger twins had a worse relationship compared to
other groups. The results of this researchemnt reveal that neurotypical child need to understand
ASD characteristics
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