1,227 research outputs found
Pension Systems in Latin America: Concepts and Measurements of Coverage
Pension systems’ performance around the world can be usually assessed by considering three dimensions: coverage, adequacy, and sustainability. This paper focuses on the coverage dimension, looking at empirical data in Latin America. It represents a review and expansion of a previous analysis (such as Rofman and Carranza, 2005), as it corrects a few methodological problems and expands the timeframe. Data were available for 18 countries, for a period that starts in the early 1990s to the mid 2000s. Recognizing the difficulties involved in comparing the available information, the paper presents a group of similar indicators that make it possible to measure coverage in the various countries, both among active workers and among the elderly. In addition, several socio-demographic characteristics of the covered population are presented and discussed, identifying relevant differentials. The covariates taken into account in the study are: age, geographical areas, sector of employment, level of education, gender, occupation, firm size, and income quintiles.Coverage, Pension Systems, Latin America.
The Legacy of Al-Andalus in Mexico: Mudejar Architecture
This article aims to approach the Mudejar architecture developed in Mexico during the
16th and 17th centuries. The subject has been little studied, although both general and specific
contributions have been made by the author’s research group. At the methodological level, this study
is based on the existing bibliography, as well as archive and field research which allow for an accurate
scientific approach and results. The article analyzes the social and productive conditions in Mexico
during the Viceregal period, along with the systematization carried by the Viceroy Antonio de
Mendoza, the guild ordinances and the architectural typologies. The perception of territory and the
use of constructive models by the Viceregal authorities would justify the use of the Mudejar style as
cultural and unity criteria.This research was funded by Andalucía y América: Patrimonio Cultural y Relaciones Artísticas
(HUM-806)
Hispanic influence in the Architecture of Havana between the nineteenth and twentieth
La independencia de Cuba a fines del siglo XIX no supuso el fin de las relaciones ni de las influencias de España en la isla. Por un lado, las asociaciones de carácter cultural relacionadas con las regiones de origen en la Península Ibérica se visualizaron con grandes arquitecturas y, por otro, las influencias formales relacionadas con el orientalismo y la Alhambra también son visibles en la arquitectura de La Habana.Cuban independence, taking place at the end of the XIXth Century, did not imply the end of the influence of, and the relationship with Spain. On the one hand, cultural associations related to different Iberian regions made themselves present in Cuban urban landscapes through remarkable architecture; on the other, formal influences related to Orientalism and Alhambra were present in Havana architecture
Elliptical galaxies: fundamental relations, environmental effects and peculiar motions
This thesis investigates the reliability of the D - σ and D - Mg(_2) distance indicators for elliptical galaxies. In particular, we test whether these empirical correlations are affected by differences in the stellar populations of elliptical galaxies associated with their environment. Our final goal is to assess the reality of the large peculiar velocities measured in the local universe as derived using these relations. Our galaxy sample includes ellipticals located in high and low galaxian density regions. The cluster sample is mainly based on new observations of ellipticals in Coma, Abell 2199 and Abell 2634, while the field sample is selected from the literature. For each galaxy we list measurements of the effective radius, effective surface brightness, photometric diameter, velocity dispersion and magnesium index. We first develop a phenomenological framework of galaxy properties that describes all empirical correlations for spheroidal systems, including both giant and dwarf ellipticals. Despite the wide variety of observed correlations, we show that only three provide independent information on the overall structure and metal abundamce of these systems. These three 'fundamental relations' can be expressed in terms of physical variables assuming that both the galaxy mass-to-light ratio (M/L) and the ratio between the effective radii of the dark and luminous matter distributions (R/R(_e)) depend on the mass of the galaxy. The structure of elliptical galaxies is then determined by both the virial theorem and aa intrinsic mass-radius relation. The metallicity of their stellar populations in turn is a function of the galaxy velocity dispersion alone. We compare this framework with a theoretical scenario of galaxy formation that combines the hierarchical clustering and the galactic wind models. This picture provides a consistent explanation of the fundamental relations of all elliptical galaxies assuming R/R(_e) ~ constant for dwarf ellipticals while, for giant ellipticals, we find that R/R(_e) must be a decreasing function of galaxy mass. Our framework strongly suggests that this dependence of R/Re on galaxy mass is the only difference between the two galaxy families. We then study the effect of the environment on the D - σ and D - Mg(_2) distance indicators by comparing ellipticals that reside in the core of the Coma cluster with those in the cluster halo. By studying the variations within one cluster, we avoid the difficulty of decoupling effects induced by distance errors from those due to real environmental differences. We find that ellipticals located in the outer, low-density areas of the Coma cluster have D diameters that are, on average at a given σ or Mg(_2), 10% or 30% larger than their counterparts in the cluster core. Using galaxy evolution models we demonstrate that this effect is consistent with the presence of an intermediate age stellar component in some halo ellipticals. We use the framework of galaxy properties in combination with galaxy evolution models to design a new age-independent distance indicator for ellipticals. This relation allows distances to be estimated with an uncertainty of ~20% and is independent of age/environmental effects. We also offer a simple explanation of the trends observed in the D - σ versus D -Mg(_2) residuals plot. Finally, we use our new distance indicator to readdress previous measurements of peculiar velocities in both the cluster and field environments. For Abell 2199 and Abell 2634 ellipticals, we show that the new distance estimates are in good agreement with those derived using the D - σ and D - Mg(_2) relations. Both clusters are found to have peculiar velocities which are not significantly different from zero. However, when the new distance indicator is applied to field ellipticals we find that the age/environmental effect translates into a spurious positive component of the local peculiar velocity field as derived from D - σ and D - Mg(_2). This effect may provide a simple explanation of the large positive peculiar motions observed towards the Great Attractor
A Skin to Live in: Geometric Parietal Paintings in the Residential Architecture of al-Andalus
Andalusi residential architecture is often described through planimetry or its internal constructive materiality. However, the real architectural vision of those who inhabited or visited Andalusi palaces or houses was completed by an important decorative epidermis that covered the structural materials and gave these Islamic buildings their final visual impact. Traditionally, the three-dimensional stone and plaster ornamentation has been the most analysed; the pictorial decoration that widely covered plinths has rarely been studied as a whole, despite the numerous remnants documented in recent decades. In this work, we propose a holistic and synthetic approach to this decorative architectural element, from its technical elaboration to its role in the three-dimensionality of Andalusi residential spaces. We also address its influences and its aesthetic evolution over the centuries
Balance del primer año académico del primer Máster en Gestión Cultural de las Universidades de Granada y Sevilla
Quest for the extra degree of freedom in ƒ <i>(T)</i> gravity
It has recently been shown that f(T) gravity has n(n−3)/2+1 physical degrees of freedom (d.o.f.) in n dimensions, contrary to previous claims. The simplest physical interpretation of this fact is that the theory possesses a scalar d.o.f. This is the case of f(R) gravity, a theory that can be understood in the Einstein frame as general relativity plus a scalaron. The scalar field that represents the extra d.o.f. in f(T) gravity encodes information about the parallelization of the spacetime, which is detected through a reinterpretation of the equations of motion in both the teleparallel Jordan and Einstein frames. The trace of the equations of motion in f(T) gravity shows the propagation of the scalar d.o.f., giving an accurate proof of its existence. We also provide a simple toy model of a physical system with rotational pseudoinvariance, like f(T) gravity, which gives insights into the physical interpretation of the extra d.o.f. We discuss some implications and unusual features of the previously worked out Hamiltonian formalism for f(T) gravity. Finally we show some mathematical tools to implement the Hamiltonian formulation in the Einstein frame of f(T) gravity, which exhibits some problems that should be addressed in future works.Instituto de Física La Plat
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