Risk transmission between Latin America stock markets and the US: impacts of the 2007/2008 Crisis

The aim of this paper is to investigate whether the US subprime financial turmoil has had any statistically significant effect on the conditional volatility of stock prices in Latin America for which the BEKK methodology is adopted, developed by Engle and Kroner (1995). The t-student distribution is employed as it can provide a best fit for financial data. In order to do this study, we will investigate four Latin America emerging capital markets (Brazil, Argentina, Chile and Mexico) and the United States, considering the period of the recent financial crisis of 2007/2008, analyzing before, during and after the crisis period. Our results show that before the crisis there is no evidence of volatility spillovers from the North American stock market to Latin American ones. During the crisis, there is evidence of volatility spillover effects on some countries. Brazil and Chile affect the US volatility and Argentina, Chile and Mexico are affected by the US's. After the crisis, the volatility of all Latin American stock markets affect and are affected by the US market. These results show an increase in spillover effects from a shock to US stock market to Latin American countries after the 2007/2008 financial crisis.financial crisis, volatility spillover, Latin America

Information profiles for DNA pattern discovery

Finite-context modeling is a powerful tool for compressing and hence for representing DNA sequences. We describe an algorithm to detect genomic regularities, within a blind discovery strategy. The algorithm uses information profiles built using suitable combinations of finite-context models. We used the genome of the fission yeast Schizosaccharomyces pombe strain 972 h- for illustration, unveilling locations of low information content, which are usually associated with DNA regions of potential biological interest.Comment: Full version of DCC 2014 paper "Information profiles for DNA pattern discovery

Transformation, partitioning and flow–deposit interactions during the run-out of megaflows

Funded by BG Brasil E&P LtdaPeer reviewedPostprin

Exchange Narrowing Effects in the EPR Linewidth of Gd Diluted in Ce Compounds

Anomalous thermal behavior on the EPR linewidths of Gd impurities diluted in Ce compounds has been observed. In metals, the local magnetic moment EPR linewidth, \Delta H, is expected to increase linearly with the temperature. In contrast, in Ce_{x}La_{1-x}Os_{2} the Gd EPR spectra show a nonlinear increase. In this work, the mechanisms that are responsible for the thermal behavior of the EPR lines in Ce_{x}La_{1-x}Os_{2} are examined. We show that the exchange interaction between the local magnetic moments and the conduction electrons are responsible for the narrowing of the spectra at low temperatures. At high temperatures, the contribution to the linewidth of the exchange interaction between the local magnetic moments and the $Ce$ ions has an exponential dependence on the excitation energy of the intermediate valent ions. A complete fitting of the EPR spectra for powdered samples is obtained.Comment: 11 pages, 1 figur

Quasi-Topological Quantum Field Theories and Z2Z_2 Lattice Gauge Theories

We consider a two parameter family of $Z_2$ gauge theories on a lattice discretization $T(M)$ of a 3-manifold $M$ and its relation to topological field theories. Familiar models such as the spin-gauge model are curves on a parameter space $\Gamma$. We show that there is a region $\Gamma_0$ of $\Gamma$ where the partition function and the expectation value of the Wilson loop for a curve $\gamma$ can be exactly computed. Depending on the point of $\Gamma_0$, the model behaves as topological or quasi-topological. The partition function is, up to a scaling factor, a topological number of $M$. The Wilson loop on the other hand, does not depend on the topology of $\gamma$. However, for a subset of $\Gamma_0$, depends on the size of $\gamma$ and follows a discrete version of an area law. At the zero temperature limit, the spin-gauge model approaches the topological and the quasi-topological regions depending on the sign of the coupling constant.Comment: 19 pages, 13 figure

Un mito del hambre en el nordeste de Brasil

El objetivo del presente estudio es permitir la comprensión, mediante un abordaje etnográfico, de los significados del hambre en las vivencias de actores sociales que enfrentan la pobreza extrema en un barrio de Salvador, Bahía, Brasil. Los relatos se han analizado con el objeto de entender la construcción de signos inherentes al sufrimiento de quienes padecen de hambre cotidianamente. En la dimensión cultural, este flagelo humano se manifiesta bajo diversas formas (metáforas); una de ellas ilustrada por el caso concreto que aquí se presenta. Se trata de la encarnación de una leyenda del sertão del nordeste de Brasil que da visibilidad al mito del hambre llamado "Romãozinho", el cual, en su configuración mítica, ataca y roba el alimento de los niños del barrio, llevándolos inexorablemente a la muerte. "Romãozinho" es una de las creaciones de la cultura del hambre presente en los sectores populares socialmente excluidos