Search results for "Pulse"

Similaritons in optical fiber Raman amplifiers

2005

This thesis presents the generation of optical similaritons in a normally dispersive Raman amplifier at telecom wavelengths. The pulses experimentally characterized by FROG technique exhibit a parabolic intensity profile with a linear chirp, in good agreement with results of numerical simulations.Several theoretical features of the similaritons have been experimentally studied. The dynamics of two similaritons with same or different central wavelengths is also investigated: similaritons are robust against collisions, whereas the interaction of similaritons leads to the generation of high-repetition rate dark soliton train.The similariton properties have been finally applied into three field…

ASSOCIATION OF RENAL RESISTIVE INDEX WITH AORTIC PULSE WAVE VELOCITY IN HYPERTENSIVE PATIENTS.

2013

The assessment of renal hemodynamic parameters by duplex Doppler sonography has been used for many years as a diagnostic tool in the daily work-up of kidney diseases. Recent data suggest that these parameters, especially the intrarenal resistive index (RI) may be also associated with systemic vascular changes and with an enhanced cardiovascular risk. However, conflicting data exist in literature about the independent association of aortic stiffness with RI. The aim of this study was to evaluate the relationship between RI and arterial stiffness, assessed by aortic pulse wave velocity (PWV), in the hypertensive subjects consecutively attending our hypertension centre. We enrolled 264 subject…

Correlations between non ivasive renal index and markers of atherosclerosis in lupus patients

2014

Recent data suggest that renal hemodynamic parameters obtained by duplex Doppler sonography, especially the intrarenal resistive index (RI), may be associated with systemic vascular changes in some groups of patients. However, conflicting data exist about the relationship between aortic stiffness and RI in autoimmune disease, like systemic lupus erythematosus, characterized by high and early incidence of atherosclerotic disease. The aim of this study was to evaluate the relationship between RI and arterial stiffness, assessed by aortic pulse wave velocity (aPWV), and carotid atherosclerosis, evaluated by intimal medial thickness measurement (IMT) in patients with SLE. DESIGN: Cross-sectiona…

Early vascular aging in normotensive subjects with systemic lupus erythematous. Comparison with young hypertensive patients

2014

early vascular aging

RELATIONSHIP BETWEEN AORTIC PULSE WAVE VELOCITY AND RENAL RESISTIVE INDEX IN HYPERTENSIVE PATIENTS.

2013

INTRODUCTION: The assessment of renal hemodynamic parameters by duplex Doppler sonography has been used for many years as a diagnostic tool in the daily workup of kidney diseases. Recent data suggest that these parameters, especially the intrarenal resistive index (RI), may be also associated with systemic vascular changes and cardiovascular risk. However, conflicting data exist about the independent association of aortic stiffness with RI. AIM: The aim was to evaluate the relationship between RI and arterial stiffness, assessed by aortic pulse wave velocity (PWV), in the hypertensive subjects consecutively attending our hypertension centre. METHODS: We enrolled 264 subjects, aged between 3…

Vascular health assessment of the hypertensive patients (VASOTENS) Registry: rationale, design and methods of an international registry for ambulator…

2015

Ambulatory (A) blood pressure (BP), central BP and pulse wave velocity (PWV) are parameters recommended by hypertension guidelines for estimating BP control and vascular impairment. Recent advances in technology made available devices allowing combined non-invasive estimation of these parameters over the 24-h during ABP monitoring (ABPM). However, at present, there is limited evidence on the usefulness of such an approach for routine hypertension managementWe recently launched an investigator-initiated, international, multicenter, observational, prospective study with the following objectives: • The evaluation of non-invasive ambulatory blood pressure and arterial stiffness estimates (throu…

A General Mathematical Model for the Simulation of Common Faults in Three‐ phase Voltage Source Inverters

2013

In the last years the fault problem in power electronics has been more and more investigated both from theoretical and practical point of view. This paper analyzes the problem of faults modeling in a three phase voltage source inverter(VSI) and presents a model of a VSI able to simulate both unfaulty and faulty conditions when one or more devices go broken. In the past the fault problem was faced step by step considering the fault on each single device building a model for each case. The model hereafter presented solves this drawback through the introduction of the concept of the Healthy Device Binary Variable (HDBV) and the more general Healthy Leg Binary Variable (HLBV) showing also as th…

Pulsed EPR analysis of tooth enamel samples exposed to UV and gamma radiations

2010

A Thermo-Kinetic Study of Titanium Oxidation Assisted by a Nd-YAG Pulsed Laser

2004

H(II) centers in natural silica under repeated UV laser irradiations

2004

We investigated the kinetics of H(II) centers (=Ge'-H) in natural silica under repeated 266nm UV irradiations performed by a Nd:YAG pulsed laser. UV photons temporarily destroy these paramagnetic defects, their reduction being complete within 250 pulses. After re-irradiation, H(II) centers grow again, and the observed recovery kinetics depends on the irradiation dose; multiple 2000 pulses re-irradiations induce the same post-irradiation kinetics of H(II) centers after each exposure cycle. The analysis of these effects allows us to achieve a deeper understanding of the dynamics of the centers during and after laser irradiation.