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Upconversion cooling of Er-doped low-phonon fluorescent solids
(American Physical Society, 2009-01)
We report on a novel mechanism for laser cooling of fluorescent solids based on infrared-to-visible upconversion often found in rare-earth-doped low-phonon materials. This type of optical cooling presents some advantages ...
Predictors of Major Infections in Systemic Lupus Erythematosus
(Biomed Central, 2009-07-15)
Introduction Infections commonly complicate the course of systemic lupus erythematosus (SLE). Our aim is to investigate the clinical predictors of major infections in patients with SLE.
Methods A nested case-control ...
Wheel-rail wear index prediction considering multiple contact patches
(Elsevier, 2009-06)
This paper shows a new wheel-rail contact model specially suited to obtain wear indexes between wheel and rail when the vehicle negotiates tight curves. The model presented in the paper enables introduction of the two ...
Influence of creep forces on the risk of derailment of railway vehicles
(Taylor & Francis, 2009)
The derailment mechanism in a railway vehicle is a complex mechanical phenomenon which has been, and still is, the subject of intense research activity due to the serious consequences it can entail. Since Nadal deduced his ...
Dynamic optimization of track components to minimize rail corrugation
(Elsevier, 2009-01)
In this paper, the influence on corrugation of the most significant track parameters has been examined. After this parametric study, the optimization of the track parameters to minimize the undulatory wear growth has been ...
The Number of Catalytic Elements Is Crucial for the Emergence of Metabolic Cores
(Public Library of Science, 2009-10-19)
Background: Different studies show evidence that several unicellular organisms display a cellular metabolic structure characterized by a set of enzymes which are always in an active state (metabolic core), while the rest ...
Position-dependent exact-exchange energy for slabs and semi-infinite jellium
(American Physical Society, 2009-12)
The position-dependent exact-exchange energy per particle epsilon(x)(z) (defined as the interaction between a given electron at z and its exact-exchange hole) at metal surfaces is investigated, by using either jellium slabs ...
Exchange-Correlation Hole of a Generalized Gradient Approximation for Solids and Surfaces
(American Physical Society, 2009-02)
We propose a generalized gradient approximation (GGA) for the angle- and system-averaged exchange-correlation hole of a many-electron system. This hole, which satisfies known exact constraints, recovers the Perdew-Burke-Ernzerhof ...
A multi-gene analysis strategy identifies metabolic pathways targeted by trans-10, cis-12-conjugated linoleic acid in the liver of hamsters
(Cambridge University Press, 2009-08-28)
In mice, hepatic functions can be greatly affected by dietary trans-10, cis-12-conjugated linoleic acid (CLA). However, this phenomenon has been less documented in hamsters. In the present study, male hamsters were fed two ...
Synthetic applications of intramolecular aza-Wittig reaction for the preparation of heterocyclic compound
(Bentham Science Publishers, 2009)
[EN] A review focused on recent advances in intramolecular aza-Wittig reaction of phosphazenes with several carbonyl or analogous compounds is reported. Phosphazenes afford intramolecular aza-Wittig reaction with different ...