941 research outputs found

    Bogomolny equations for vortices in the noncommutative torus

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    We derive Bogomolny-type equations for the abelian Higgs model defined on the noncommutative torus and discuss its vortex like solutions. To this end, we carefully analyze how periodic boundary conditions have to be handled in noncommutative space and discuss how vortex solutions are constructed. We also consider the extension to an U(2) × U(1) model, a simplified prototype of the noncommutative standard model.Facultad de Ciencias Exacta

    A Case-Control Study of Cognitive Function in Patients with End-Stage Renal Disease Before and After Hemodialysis in Southern Spain

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    BACKGROUND: This single-center study aimed to investigate the effects of repetitive transcranial magnetic stimulation (rTMS) on modulation of thyroid hormone levels and cognition in the recovery stage of patients with cognitive dysfunction following stroke. MATERIAL AND METHODS: Seventy post-stroke patients who had cognitive impairment were randomly assigned to either the rTMS group or the control (sham) group. Both groups were administered basic treatment, with the rTMS group receiving rTMS (1 Hz, 90% MT, 1000 pulse/20 min, once a day for 5 days, for a total of 20 times), the stimulation site was the contralateral dorsolateral prefrontal cortex (DLPFC), and the sham group receiving sham stimulation which had the same stimulation parameters and site, except that the coil plane was placed perpendicular to the surface of the scalp. Cognitive function assessment and thyroid function tests were performed before and after 4 weeks of treatment. RESULTS: Serum levels of triiodothyronine (T3), free triiodothyronine (FT3), and thyroid stimulating hormone (TSH) showed a positive correlation with Montreal Cognitive Assessment (MoCA) scale score of stroke patients in the recovery phase. The post-treatment change in the scores of MoCA and Modified Barthel Index (MBI) and scores of 3 cognitive domains (visuospatial function, memory, and attention), as well as serum T3, FT3, and TSH levels, were improved more significantly in the rTMS group, and T3 and FT3 levels significantly affected the MoCA scores within the reference range. CONCLUSIONS: Serum T3, FT3, and TSH levels of stroke patients in the recovery phase were positively correlated with MoCA score. rTMS increased T3, FT3, and TSH levels and also improved MoCA and MBI of patients in the recovery phase of stroke

    Bogomolny equations for vortices in the noncommutative torus

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    We derive Bogomolny-type equations for the Abelian Higgs model defined on the noncommutative torus and discuss its vortex like solutions. To this end, we carefully analyze how periodic boundary conditions have to be handled in noncommutative space and discussed how vortex solutions are constructed. We also consider the extension to an U(2)×U(1)U(2)\times U(1) model, a simplified prototype of the noncommutative standard model.Comment: 23 pages, no figure

    Bogomolny equations for vortices in the noncommutative torus

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    We derive Bogomolny-type equations for the abelian Higgs model defined on the noncommutative torus and discuss its vortex like solutions. To this end, we carefully analyze how periodic boundary conditions have to be handled in noncommutative space and discuss how vortex solutions are constructed. We also consider the extension to an U(2) × U(1) model, a simplified prototype of the noncommutative standard model.Facultad de Ciencias Exacta

    Gamma rays from clumpy wind-jet interactions in high-mass microquasars

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    Context. The stellar winds of the massive stars in high-mass microquasars are thought to be inhomogeneous. The interaction of these inhomogeneities, or clumps, with the jets of these objects may be a major factor in gamma-ray production. Aims. Our goal is to characterize a typical scenario of clump-jet interaction, and calculate the contribution of these interactions to the gamma-ray emission from these systems. Methods. We use axisymmetric, relativistic hydrodynamical simulations to model the emitting flow in a typical clump-jet interaction. Using the simulation results we perform a numerical calculation of the high-energy emission from one of these interactions. The radiative calculations are performed for relativistic electrons locally accelerated at the jet shock, and the synchrotron and inverse Compton radiation spectra are computed for different stages of the shocked clump evolution. We also explore different parameter values, such as viewing angle and magnetic field strength. The results derived from one clump-jet interaction are generalized phenomenologically to multiple interactions under different wind models, estimating the clump-jet interaction rates, and the resulting luminosities in the GeV range. Results. If particles are efficiently accelerated in clump-jet interactions, the apparent gamma-ray luminosity through inverse Compton scattering with the stellar photons can be significant even for rather strong magnetic fields and thus efficient synchrotron cooling. Moreover, despite the standing nature or slow motion of the jet shocks for most of the interaction stage, Doppler boosting in the postshock flow is relevant even for mildly relativistic jets. Conclusions. For clump-to-average wind density contrasts greater than or equal to ten, clump-jet interactions could be bright enough to match the observed GeV luminosity in Cyg X-1 and Cyg X-3 when a jet is present in these sources, with required non-thermal-to-total available power fractions greater than 0.01 and 0.1, respectively

    Consumer Attitudes Toward Animal Welfare-Friendly Products and Willingness to Pay: Exploration of Mexican Market Segments

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    The study aim was to identify consumer segmentation based on nonhuman animal welfare (AW) attitudes and their relationship with demographic features and willingness to pay (WTP) for welfare-friendly products (WFP) in Mexico. Personal interviews were conducted with 843 Mexican consumers who stated they purchased most of the animal products in their home. Respondents were selected using a quota sampling method with age, gender, education, and origin as quota control variables. The multivariate analysis suggested there were three clusters or consumer profiles labeled "skeptical, " "concerned, " and "ethical, " which helped explain the association between AW attitudes, some demographic variables, and WTP for WFP. This study is one of the first to address consumer profiling in Latin America, and the findings could have implications for the commercialization of WFP. Hence, customers should receive information to consider welfare innovations when deciding to purchase animal products. The growth of the WFP food market establishes an element of a far more multifaceted phenomenon of sustainable consumption and support of a new paradigm called responsible marketing in emerging markets such as Mexico

    Evaluación genética: un paso inicial para mejorar la producción bovina

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    El 65% de la población bovina mundial se encuentra en los países tropicales y solo un 35% en los países desarrollados. pero estos últimos producen el 10% más de leche y el 4% más de carne. Uno de los factores que ha incidido en la eficiencia de la producción de carne y leche de los países desarrollados ha sido la utilización de los registros y el análisis de la información acerca de las características productivas y reproductivas de los hatos. tomada en la empresa ganadera. Ello ha permitido. a su vez. el diseño y la puesta en marcha de programas de mejoramiento genético. con el objetivo de seleccionar para la producción y la cría los mejores animales bajo las condiciones de cada país en particular.Ganadería bovin

    Non BPS noncommutative vortices

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    We construct exact vortex solutions to the equations of motion of the Abelian Higgs model defined in non commutative space, analyzing in detail the properties of these solutions beyond the BPS point. We show that our solutions behave as smooth deformations of vortices in ordinary space time except for parity symmetry breaking effects induced by the non commutative parameter θ\theta.Comment: 17 pages, 5 figure
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