782 research outputs found
Aplicación de la tecnología audiovisual a la docencia de fisiología y toxicología, elaboración de video animado de la fisiología de la nefrona y de la fisiopatología del fracaso renal agudo de origen tóxico.
Memoria ID-204. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2013-2014
Characterization of Gain-Switched Pulses from 1.55 µm VCSEL
We report on short optical pulse generation by gain-switching (GS) a low-cost commercial vertical-cavity surface-emitting laser emitting at 1.55 μm. The dependence of pulse characteristics on GS parameters is investigated and analyzed. Pulses with duration of 55 ps and time-bandwidth product between 0.91 and 2.2 are obtained at repetition rates between 1 and 3 GHz
Etiopathology of chronic tubular, glomerular and renovascular nephropathies: Clinical implications
Chronic kidney disease (CKD) comprises a group of pathologies in which the renal excretory function is chronically compromised. Most, but not all, forms of CKD are progressive and irreversible, pathological syndromes that start silently (i.e. no functional alterations are evident), continue through renal dysfunction and ends up in renal failure. At this point, kidney transplant or dialysis (renal replacement therapy, RRT) becomes necessary to prevent death derived from the inability of the kidneys to cleanse the blood and achieve hydroelectrolytic balance. Worldwide, nearly 1.5 million people need RRT, and the incidence of CKD has increased significantly over the last decades. Diabetes and hypertension are among the leading causes of end stage renal disease, although autoimmunity, renal atherosclerosis, certain infections, drugs and toxins, obstruction of the urinary tract, genetic alterations, and other insults may initiate the disease by damaging the glomerular, tubular, vascular or interstitial compartments of the kidneys. In all cases, CKD eventually compromises all these structures and gives rise to a similar phenotype regardless of etiology. This review describes with an integrative approach the pathophysiological process of tubulointerstitial, glomerular and renovascular diseases, and makes emphasis on the key cellular and molecular events involved. It further analyses the key mechanisms leading to a merging phenotype and pathophysiological scenario as etiologically distinct diseases progress. Finally clinical implications and future experimental and therapeutic perspectives are discussed
Aplicación de la tecnología audiovisual a la docencia de fisiología y toxicología, elaboración de vídeo animado de la fisiología de la nefrona y de la fisiopatología del fracaso renal agudo de origen tóxico II
Memoria ID-0169. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2014-2015
Crystallization and melting of bacteria colonies and Brownian Bugs
Motivated by the existence of remarkably ordered cluster arrays of bacteria
colonies growing in Petri dishes and related problems, we study the spontaneous
emergence of clustering and patterns in a simple nonequilibrium system: the
individual-based interacting Brownian bug model. We map this discrete model
into a continuous Langevin equation which is the starting point for our
extensive numerical analyses. For the two-dimensional case we report on the
spontaneous generation of localized clusters of activity as well as a
melting/freezing transition from a disordered or isotropic phase to an ordered
one characterized by hexagonal patterns. We study in detail the analogies and
differences with the well-established Kosterlitz-Thouless-Halperin-Nelson-Young
theory of equilibrium melting, as well as with another competing theory. For
that, we study translational and orientational correlations and perform a
careful defect analysis. We find a non standard one-stage, defect-mediated,
transition whose nature is only partially elucidated.Comment: 13 Figures. 14 pages. Submitted to Phys. Rev.
Negative pressures in CaWO4 nanocrystals
Tetragonal scheelite-type CaWO4 nanocrystals recently prepared by a hydrothermal method show an enhancement of its structural symmetry with the decrease in nanocrystal size. The analysis of the volume dependence of the structural parameters in CaWO4 nanocrystals with the help of ab initio total-energy calculations shows that the enhancement of the symmetry in the scheelite-type nanocrystals is a consequence of the negative pressure exerted on the nanocrystals; i.e., the nanocrystals are under tension. Besides, the behavior of the structural parameters in CaWO4 nanocrystals for sizes below 10 nm suggests an onset of a scheelite-to-zircon phase transformation in good agreement with the predictions from our ab initio calculations. CaWO4 nanocrystals exhibit a reconstructive-type mechanism for the scheelite-to-zircon phase transition that seems to follow the tetragonal path that links both structures. This result is in contrast with the mechanism recently proposed for this transition in bulk ZrSiO4 where the transition goes through an intermediate monoclinic [email protected]
Uso de hardware reconfigurable a través de servicios Web en aplicaciones distribuidas
Este artículo propone una solución sencilla para la utilización de
hardware reconfigurable en el contexto de aplicaciones distribuidas. Se ha elegido
la tecnología de Servicios Web para proporcionar el acceso remoto a la
plataforma reconfigurable. El objetivo es aprovechar las características propias
de este tipo de servicios que facilitan el desarrollo de aplicaciones distribuidas
junto con las ventajas de utilizar hadrware específico para acelerar el tiempo de
ejecución de una tarea crítica. En particular, se ha desarrollado un servicio web
para ofrecer, de forma remota, toda la funcionalidad de la plataforma
RC1000PP a través de Intenet. Además de las funciones básicas se propone una
metodología para el desarrollo de rutinas especializadas de alto nivel, que una
vez publicadas, se ofertan para su integración como elemento de proceso en una
aplicación distribuida. Con un ejemplo se comprueban las ventajas de esta metodología
y se presentan los resultados preliminares del desarrollo de una aplicación.Este trabajo ha sido financiado por la Comunidad Autónoma de Madrid con el número
de proyecto 07T/0052/2003-3, y parcialmente financiado por el Programa Europeo
No: 100671-CP-1-2002-1-FR-MINERVA-M
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