Increased Urinary Erythropoietin Excretion in Severe Sleep Apnea-Hipoapnea Syndrome: The Effect of CPAP.

Introduction: Tissue hypoxia stimulates the production of erythropoietin (EPO), the main effect of which is, in turn, to stimulate erythropoiesis. Sleep apnea-hypopnea syndrome (SAHS) is an entity characterized by repeated episodes of hypoxemia during sleep.

Objective: To analyze whether hypoxemia stimulated increased urinary excretion of EPO, and if so, to evaluate if treatment with continuous positive airway pressure (CPAP) can inhibit this phenomenon.

Quantum correlations and energy currents across three dissipative oscillators.

We present a study that addresses both the stationary properties of the energy current and quantum correlations in a three-mode chain subjected to Ohmic and super-Ohmic dissipations. An extensive numerical analysis shows that the mean value and the fluctuations of the energy current remain insensitive to the emergence of a rich variety of quantum correlations, such as two-mode discord and entanglement and bipartite three-mode and genuine tripartite entanglement. The discussion of the numerical results is based on the derived expressions for the stationary properties in terms of the two-time correlation functions of the oscillator operators, which carry the quantum correlations.

Effects of classical nonlinear resonances in grazing diatom-surface collisions.

Energy transfer between vibrational, rotational, and translational degrees of freedom of a molecule during a collision process is enhanced when the classical frequencies associated with the initial state are in the proximity of nonlinear resonance conditions. We present an analysis of the classical resonant effects in the collisions of light diatoms with periodic surfaces, and discuss the initial conditions in which these effects can be observed. In particular, we find that for grazing incidence and resonant initial values of the classical frequencies, corresponding to specific vibro-rotational molecular states and translational energies, an efficient energy transfer between the intramolecular vibro-rotational degrees of freedom and the translational degree of freedom along a symmetry direction on the surface can be found.

Nearly resonant multidimensional systems under a transient perturbative interaction.

We analyze the response of a classical system with N>or=2 internal degrees of freedom satisfying R View Article and Find Full Text PDF

Development of a questionnaire to evaluate coping strategies for skin problems.

The aim of this work was to develop an instrument (Coping Strategies for Skin Problems Questionnaire) suitable for identifying the coping strategies people use for general skin problems. We analyzed its psychometric properties when applied to a sample of 299 individuals. Factor analysis shows a 6-factor structure referring to the wish to change, problem-solving strategies, the search for information and asking for social support, the ability to distance oneself from the problem and to see the positive aspects of the situation.

[Impact of low-level expression dermatological diseases on the quality of life as a function of its level of specificity].

The impact of dermatological diseases on the quality of life is relatively well established, although some results do not support this relationship. Whereas a few studies indicate a decrease in various indicators of quality of life in conditions of disease, in other studies, this effect has not been observed. These differences can be explained by the use of different concepts of quality of life and/or the comparison of different severity levels of the diseases.

Quasiresonance: switching internal energy transfer on and off.

Quasiresonance involves a slow "external" switching on and off of an interaction between internal degrees of freedom described by action-angle variables having approximate resonances. The resonances or near-resonances spawn slow coordinates that fail to be adiabatic, but the remaining coordinates may be fast enough to have conserved actions. The interaction either can be imposed externally as a time dependent coupling or can arise autonomously due to interactions with other degrees of freedom.