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Saltillo, Mexico

The Autonomous University of Coahuila is a state university founded in 1957. It is located in the northern Mexican state of Coahuila. The university system has three campuses — Saltillo, Torreón, and Norte — distributed among the most populated cities in the state. It perhaps the only one university in the world which is governed by a President elected for a period of 3 years by direct general balloting by the unqualified vote of both students and teachers. Wikipedia.

Coccidioidomycosis results from inhaling the spores (arthroconidia) of Coccidioides species (Coccidioides immitis or Coccidioides posadasii). Tuberculosis is caused by the Mycobacterium tuberculosis complex, classified as acid-fast bacilli. It is most commonly transmitted from a patient with infectious pulmonary tuberculosis to other persons by droplet nuclei, which are aerosolized by coughing, sneezing, or speaking. Northern Mexico is an endemic zone for coccidioidomycosis and tuberculosis, both diseases usually appear in an isolated way. However, in cases of immunosuppressant in endemic zones, both pathologies tend to coexist. In all of the cases, determining the correct diagnosis is very difficult because they share epidemiological, clinical, radiographic, and even histopathological characteristics. In this paper we present two cases of tuberculosis and coccidioidomycosis coexistence. One case presented pulmonary disease from both entities, while the other was a relapsing of disseminated coccidioidomycosis associated with systemic tuberculosis. The presence of similar cases should alert the clinician to consider an early diagnosis of both entities in every patient with compatible clinical features. The most important concept is to remember that the diagnosis of one of them doesn't exclude the possible existence of the other. Source

Delgado-Acosta E.G.,Autonomous University of San Luis Potosi | Kirchbach M.,Autonomous University of San Luis Potosi | Napsuciale M.,University of Guanajuato | Rodriguez S.,Autonomous University of Coahuila
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

We study multipole decompositions of the electromagnetic currents of spin-1/2, 1, and 3/2 particles described in terms of representation-specific wave equations which are second order in the momenta and which emerge within the recently elaborated Poincaré covariant-projector method, where the respective Lagrangians explicitly depend on the Lorentz group generators of the representations of interest. The currents are then the ordinary linear Noether currents related to phase invariance, and present themselves always as two-terms motion-plus spin-magnetization currents. The spin-magnetization currents appear weighted by the gyromagnetic ratio g, a free parameter in the method which we fix either by unitarity of forward Compton scattering amplitudes in the ultraviolet for spin-1 and spin-3/2, or in the spin-1/2 case, by their asymptotic vanishing, thus ending up in all three cases with the universal g value of g=2. Within the method under discussion, we calculate the electric multipoles of the above spins for the spinor, the four-vector, and the four-vector-spinor representations, and find it favorable in some aspects, specifically in comparison with the conventional Proca and Rarita-Schwinger frameworks. We furthermore attend to the most general non-Lagrangian spin-3/2 currents, which are allowed by Lorentz invariance to be up to third order in the momenta and construct the linear-current equivalent of identical multipole moments of one of them. We conclude that nonlinear non-Lagrangian spin-3/2 currents are not necessarily more general and more advantageous than the linear spin-3/2 Lagrangian current emerging within the covariant-projector formalism. Finally, we test the representation dependence of the multipoles by placing spin-1 and spin-3/2 in the respective (1,0)(0,1) and (3/2,0)(0,3/2) single-spin representations. We observe representation independence of the charge monopoles and the magnetic dipoles, in contrast to the higher multipoles, which turn out to be representation-dependent. In particular, we find the bi-vector (1,0)(0,1) to be characterized by an electric quadrupole moment of opposite sign to the one found in (1/2,1/2), and consequently to the W boson. This observation allows us to explain the positive electric quadrupole moment of the ρ meson extracted from recent analyses of the ρ meson electric form factor. Our finding points toward the possibility that the ρ-meson could transform as part of an antisymmetric tensor with an a 1 mesonlike state as its representation companion, a possibility consistent with the empirically established ρ and a 1 vector meson dominance of the hadronic vector and axial-vector currents. © 2012 American Physical Society. Source

Calderon G.,Autonomous University of Coahuila
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

Nonleptonic two-body B decays including radially excited π(1300) or ρ(1450) mesons in the final state are studied using the framework of a generalized naive factorization approach. Branching ratios and CP asymmetries of B→Pπ(1300), B→Vπ(1300), B→Pρ(1450) and B→Vρ(1450) decays are calculated, where P and V stand for pseudoscalar and vector charmless mesons. Form factors for B→π(1300) and B→ρ(1450) transitions are estimated in the improved version of the Isgur-Scora-Grinstein-Wise quark model. In some processes, CP asymmetries of more than 10% and branching ratios of 10 -5 order are found, which could be reached in experiments. © 2012 American Physical Society. Source

Rey S.J.,Arizona State University | Sastre Gutierrez M.L.,Autonomous University of Coahuila
Applied Geography | Year: 2015

In this paper we examine the trajectory of regional income inequality dynamics for two neighboring national systems. Using data on 3038 US counties and 2418 Mexico municipios, from 2000, 2005, and 2010, we employ recent extensions of spatial Markov chains and space-time mobility measures, to consider the following questions: Are regional inequality dynamics fundamentally distinct between Mexico and the United States? Does the role of spatial context influence the distributional dynamics of the two systems? Finally we examine if there is a distinct international border region that displays inequality dynamics different from those of the internal regions of the two national systems. Strong evidence of spatial heterogeneity in regional income mobility is found between the two national systems, with Mexico having higher mobility relative to the US. The international border region is found to have distinct mobility dynamics from either national system, experiencing the strongest mobility. Extensive evidence of spatial contextual effects are found throughout the US-Mexican pooled data set indicating that a region's transitional dynamics are influenced by incomes of neighboring regions. © 2015 Elsevier Ltd. Source

Mendoza-Mendoza E.,CINVESTAV | Montemayor S.M.,Autonomous University of Coahuila | Escalante-Garcia J.I.,CINVESTAV | Fuentes A.F.,CINVESTAV
Journal of the American Ceramic Society | Year: 2012

Perovskite-type LaAlO 3 nanoparticles have been prepared by a facile, rapid, and environmentally friendly molten salts method using alkali metal nitrates as low-temperature fluxes. Starting from hydrated lanthanum and aluminum nitrates and alkali metal hydroxides, the proposed methodology consists briefly of two steps: a mechanically induced metathesis reaction followed by short firing at temperatures above nitrates melting points. The purpose of the first is twofold: on the one hand to generate in situ the alkali metal nitrate flux and on the other hand, to obtain a La and Al-containing precursor material suitable for the synthesis of bulk LaAlO 3 nanoparticles in molten nitrates. Different alkali metal nitrates and eutectic mixtures were used to analyze the influence of melt basicity in the reaction outcome. Single phase LaAlO 3 was obtained directly, without any purification step when using three molten media: LiNO 3, NaNO 3, and their mixture; using KNO 3 as flux either alone or as part of eutectic compositions, prevents complete conversion, and the title material is obtained mixed with additional crystalline phases such as lanthanum hydroxinitrates and carbonates. As-prepared LaAlO 3 powders are composed of loosely agglomerated nanoparticles with very fine crystallite size (32-45 nm). The present method reduces considerably previously reported synthesis time/temperatures for this material. © 2012 The American Ceramic Society. Source

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