1,610 research outputs found
Experiencia de evaluación externa de las Universidades
Este artículo se propone analizar la
evaluación externa de la enseñanza, la investigación
y los servicios académicos de
las titulaciones en el contexto del Plan Nacional
de Evaluación de la Calidad de las
Universidades (Consejo de Universidades,
1995) y del Programa de Evaluación de la
Calidad de la Enseñanza Superior de la
Universitat de Barcelona (1995). Los procedimientos
e instrumentos para cada fase
de evaluación son presentados en otros artículos
del número 315 de esta Revista (Rodríguez,
1998). Por lo tanto, tras una breve
contextualización nos centraremos en el
análisis de las condiciones previas, del desarrollo
del proceso y de los resultados de
la experiencia de la evaluación externa
P164 Effects of reduced oxygen tension and long-term mechanical stimulation on chondrocytes-polymer constructs
Explicit coercivity estimates for the linearized Boltzmann and Landau operators
We prove explicit coercivity estimates for the linearized Boltzmann and
Landau operators, for a general class of interactions including any
inverse-power law interactions, and hard spheres. The functional spaces of
these coercivity estimates depend on the collision kernel of these operators.
They cover the spectral gap estimates for the linearized Boltzmann operator
with Maxwell molecules, improve these estimates for hard potentials, and are
the first explicit coercivity estimates for soft potentials (including in
particular the case of Coulombian interactions). We also prove a regularity
property for the linearized Boltzmann operator with non locally integrable
collision kernels, and we deduce from it a new proof of the compactness of its
resolvent for hard potentials without angular cutoff.Comment: 32 page
Blow-up of the hyperbolic Burgers equation
The memory effects on microscopic kinetic systems have been sometimes
modelled by means of the introduction of second order time derivatives in the
macroscopic hydrodynamic equations. One prototypical example is the hyperbolic
modification of the Burgers equation, that has been introduced to clarify the
interplay of hyperbolicity and nonlinear hydrodynamic evolution. Previous
studies suggested the finite time blow-up of this equation, and here we present
a rigorous proof of this fact
Strong Shock Waves and Nonequilibrium Response in a One-dimensional Gas: a Boltzmann Equation Approach
We investigate the nonequilibrium behavior of a one-dimensional binary fluid
on the basis of Boltzmann equation, using an infinitely strong shock wave as
probe. Density, velocity and temperature profiles are obtained as a function of
the mixture mass ratio \mu. We show that temperature overshoots near the shock
layer, and that heavy particles are denser, slower and cooler than light
particles in the strong nonequilibrium region around the shock. The shock width
w(\mu), which characterizes the size of this region, decreases as w(\mu) ~
\mu^{1/3} for \mu-->0. In this limit, two very different length scales control
the fluid structure, with heavy particles equilibrating much faster than light
ones. Hydrodynamic fields relax exponentially toward equilibrium, \phi(x) ~
exp[-x/\lambda]. The scale separation is also apparent here, with two typical
scales, \lambda_1 and \lambda_2, such that \lambda_1 ~ \mu^{1/2} as \mu-->0$,
while \lambda_2, which is the slow scale controlling the fluid's asymptotic
relaxation, increases to a constant value in this limit. These results are
discussed at the light of recent numerical studies on the nonequilibrium
behavior of similar 1d binary fluids.Comment: 9 pages, 8 figs, published versio
Detection of the glucocorticoid receptors in brain protein extracts by SDS-PAGE
Uncorrected proofGlucocorticoids are steroid hormones vital for organ system homeostasis and for the maintenance of essential biological processes. A significant part of these actions are mediated through glucocorticoid receptor (GR) that belongs to the nuclear receptor superfamily. To cover such variety of processes the different glucocorticoids act through different GR isoforms that are originated due to posttranscriptional and posttranslational mechanisms. For this reason when evaluating the levels of GRs we should preferentially determine protein levels instead of gene expression. Here, we describe the detection by Western blotting of the GR (a and ß isoforms) protein, using macrodissected brain tissue
Relativistic Dissipative Hydrodynamics: A Minimal Causal Theory
We present a new formalism for the theory of relativistic dissipative
hydrodynamics. Here, we look for the minimal structure of such a theory which
satisfies the covariance and causality by introducing the memory effect in
irreversible currents. Our theory has a much simpler structure and thus has
several advantages for practical purposes compared to the Israel-Stewart theory
(IS). It can readily be applied to the full three-dimensional hydrodynamical
calculations. We apply our formalism to the Bjorken model and the results are
shown to be analogous to the IS.Comment: 25 pages, 2 figures, Phys. Rev. C in pres
A causal statistical family of dissipative divergence type fluids
In this paper we investigate some properties, including causality, of a
particular class of relativistic dissipative fluid theories of divergence type.
This set is defined as those theories coming from a statistical description of
matter, in the sense that the three tensor fields appearing in the theory can
be expressed as the three first momenta of a suitable distribution function. In
this set of theories the causality condition for the resulting system of
hyperbolic partial differential equations is very simple and allow to identify
a subclass of manifestly causal theories, which are so for all states outside
equilibrium for which the theory preserves this statistical interpretation
condition. This subclass includes the usual equilibrium distributions, namely
Boltzmann, Bose or Fermi distributions, according to the statistics used,
suitably generalized outside equilibrium. Therefore this gives a simple proof
that they are causal in a neighborhood of equilibrium. We also find a bigger
set of dissipative divergence type theories which are only pseudo-statistical,
in the sense that the third rank tensor of the fluid theory has the symmetry
and trace properties of a third momentum of an statistical distribution, but
the energy-momentum tensor, while having the form of a second momentum
distribution, it is so for a different distribution function. This set also
contains a subclass (including the one already mentioned) of manifestly causal
theories.Comment: LaTex, documentstyle{article
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