Search results for "Direct"

Hemodiálisis musical para mejorar la ansiedad y depresión

2020

[ES] Siempre ha habido consciencia de los efectos musicales en las personas y en la sociedad, por lo que ha resultado necesaria la aplicación de la música en la curación de pacientes, en la educación, en la expresión de las emociones y en otras muchas situaciones, como así dan fe una larga lista de opiniones y testimonios literarios. Se sabe que el efecto directo de la música ha sido estudiado en diferentes patologías durante los últimos años , a través de la musicoterapia, por los efectos positivos que tiene para la salud, pero en este estudio, la música clásica se escucha en directo, lo que es bastante novedoso y hay pocas evidencias científicas de sus beneficios. El objetivo de nuestro e…

Boundary-layer Flows Past an Hemispherical Roughness Element: DNS, Global Stability and Sensitivity Analysis

2015

Abstract We investigate the full three-dimensional instability mechanism arising in the wake of an hemispherical roughness element immersed in a laminar Blasius boundary layer. The inherent three-dimensional flow pattern beyond the critical Reynolds number is characterized by coherent vortical structures called hairpin vortices. Direct numerical simulation is used to analyze the formation and the shedding of hairpin packets inside the shear layer. The first bifurcation characteristics are investigated by global stability tools. We show the spatial structure of the linear direct and adjoint global eigenmodes of the linearized Navier-Stokes operator and use structural sensitivity analysis to …

On solving separable block tridiagonal linear systems using a GPU implementation of radix-4 PSCR method

2018

Partial solution variant of the cyclic reduction (PSCR) method is a direct solver that can be applied to certain types of separable block tridiagonal linear systems. Such linear systems arise, e.g., from the Poisson and the Helmholtz equations discretized with bilinear finite-elements. Furthermore, the separability of the linear system entails that the discretization domain has to be rectangular and the discretization mesh orthogonal. A generalized graphics processing unit (GPU) implementation of the PSCR method is presented. The numerical results indicate up to 24-fold speedups when compared to an equivalent CPU implementation that utilizes a single CPU core. Attained floating point perfor…

Advanced Virgo Status

2015

Abstract The detection of a gravitational wave signal in September 2015 by LIGO interferometers, announced jointly by LIGO collaboration and Virgo collaboration in February 2016, opened a new era in Astrophysics and brought to the whole community a new way to look at - or “listen” to - the Universe. In this regard, the next big step was the joint observation with at least three detectors at the same time. This configuration provides a twofold benefit: it increases the signal-to-noise ratio of the events by means of triple coincidence and allows a narrower pinpointing of GW sources, and, in turn, the search for Electromagnetic counterparts to GW signals. Advanced Virgo (AdV) is the second ge…

Structure-based engineering of strictosidine synthase: auxiliary for alkaloid libraries.

2007

SummaryThe highly substrate-specific strictosidine synthase (EC 4.3.3.2) catalyzes the biological Pictet-Spengler condensation between tryptamine and secologanin, leading to the synthesis of about 2000 monoterpenoid indole alkaloids in higher plants. The crystal structure of Rauvolfia serpentina strictosidine synthase (STR1) in complex with strictosidine has been elucidated here, allowing the rational site-directed mutation of the active center of STR1 and resulting in modulation of its substrate acceptance. Here, we report on the rational redesign of STR1 by generation of a Val208Ala mutant, further describing the influence on substrate acceptance and the enzyme-catalyzed synthesis of 10-m…

A dynamic subgrid-scale tensorial eddy viscosity model

1999

In the Navier-Stokes equations the removal of the turbulent fluctuating velocities with a frequency above a certain fixed threshold, employed in the Large Eddy Simulation (LES), causes the appearance of a turbulent stress tensor that requires a number of closure assumptions. In this paper insufficiencies are demonstrated for those closure models which are based on a scalar eddy viscosity coefficient. A new model, based on a tensorial eddy viscosity, is therefore proposed; it employs the Germano identity [1] and allows dynamical evaluation of the single required input coefficient. The tensorial expression for the eddy viscosity is deduced by removing the widely used scalar assumption of the …

Direct Numerical Simulation of Pulsatile Turbulent Channel Flow

2008

Influence of geographical extent on typology- and model-based assessments of taxonomic completeness of river macroinvertebrates

2009

Summary 1. River InVertebrate Prediction and Classification System (RIVPACS)-type predictive models are increasingly used to assess the biological condition of freshwaters, but management schemes may also be based on a priori groupings of similar water bodies (typologies) to control for natural variation in biota. The two approaches may lead to disagreements of the biological status of a site, depending on, for example, the spatial scale at which assessments are conducted. 2. We used data from 96 reference and 134 potentially impacted sites from Western and Central Finland to compare RIVPACS-type models and a simple size-based typology of rivers for the assessment of taxonomic completeness …

The role of Mediterranean wetlands in climate regulation and greenhouse gases exchanges: from carbon biogeochemistry to European water and nature Dir…

2022

Atesa la seua alta activitat biogeoquímica, els aiguamolls són un dels tipus d'ecosistemes més actius en el cicle global del carboni, amb altes taxes d'intercanvi de carboni i de gasos d'efecte hivernacle (GEH), i, per tant, un gran potencial de regulació climàtica. Una de les parts més importants de la biogeoquímica del carboni als aiguamolls està lligada a les taxes metabòliques, a partir del coneixement de les quals es pot determinar un balanç de carboni associat amb el potencial intercanvi de carboni amb l'atmosfera. La seua capacitat per retindre carboni i mitigar el canvi climàtic, o, per contra, d'alliberar més GEH, i contribuir a l'escalfament global, es determina pel balanç de carb…

Resistencia a nuevos antivirales de acción directa en aislados clínicos del virus de la hepatitis C

2014

La infección crónica provocada por el virus de la hepatitis C (VHC) sigue siendo un problema de salud pública a nivel mundial y en España, ocasionando unas 10.000 muertes al año. Se estima que el 3% de la población mundial (200 millones de personas en el mundo y unas 900.000 en España) se encuentran infectadas por este virus. En España, y en el resto de países Occidentales, además de ser la principal causa de hepatitis crónica, cirrosis y carcinoma hepatocelular, la infección por VHC es la indicación más frecuente de trasplante hepático. El tratamiento convencional basado sólo en interferón pegilado más ribavirina (peg-IFN-α/RBV), provoca numerosos efectos secundarios, es de larga duración …