The impulse oscillation system (IOS) measures respiratory impedance (Zrs) in terms of resistance (Rrs) and reactance (Xrs) at multiples of 5 Hz. These measurements can be used clinically to help diagnose and monitor respiratory disorders, independent of effort. There is, as yet, no information on reference values for IOS in Iranian adolescents.The predictive equation for resistance and impedanc...

BACKGROUND The forced oscillation technique (FOT) is a simple method for assessing the oscillatory mechanics of the respiratory system. The oscillatory properties, respiratory system resistance (Rrs) and reactance (Xrs), are calculated from the oscillatory pressure/flow relationship. Although the FOT has been a well-established technique, some detailed experimental conditions would be different...

Respiratory diseases, especially asthma, are common in children. While spirometry contributes to asthma diagnosis and management in older children, it has a limited role in younger children whom are often unable to perform forced expiratory manoeuvre. The development of novel diagnostic methods which require minimal effort, such as forced oscillation technique (FOT) is, therefore, a welcome and...

Abstract: A simple topology for the realization of negative type differential difference current conveyor (DDCC-) is presented. The proposed topology is based on floating output transconductor (FOT) circuits. A CMOS realization of this type current conveyor, which is made up from floating current sources (FCS), is given. Design details and simulation results using PSPICE are given to verify pre...

Lung ventilation of tetrapods that synchronize their locomotory and ventilatory cycles during exercise could be economized if the resonant frequency of the respiratory system matched the animal's preferred step frequency. To test whether animals utilize this strategy, the input impedance of the respiratory system of five anesthetized, supine guinea fowl (Numida meleagris) was measured using a f...

We consider a nonlinear time fractional partial differential equation with forced term subject to the Neumann boundary condition. Several sufficient conditions are established for oscillation of solutions of such equation by using the integral averaging method and a generalized Riccati technique. The main results are illustrated by examples. 2014 Elsevier Inc. All rights reserved.

OBJECTIVES To assess, in acutely ill asthmatic children, the feasibility of obtaining reproducible measurements of two independent lung function tests, namely spirometry and respiratory resistance, using the forced oscillation technique (Rfo). DESIGN/SETTING A prospective observational study of 150 previously untrained children, aged 2 to 17 years, treated for acute asthma in a tertiary-care ...

Numerical simulations of the interaction between a circular cylinder and its wake during both forced and free, vortex-induced, oscillation have been performed using a spectral element method in which the computational mesh was fixed to the cylinder and the Navier-Stokes equations solved in this accelerating reference frame. Thus far, work has focussed on cross flow, rather than in-line oscillat...

OBJECTIVES Silicosis is a chronic and incurable occupational disease that can progress even after the cessation of exposure. Recent studies suggest that the forced oscillation technique may help to clarify the changes in lung mechanics resulting from silicosis as well as the detection of these changes. We investigated the effects of airway obstruction in silicosis on respiratory impedance and e...

OBJECTIVE Recent work has suggested that within-breath respiratory impedance measurements performed using the forced oscillation technique may help to noninvasively evaluate respiratory mechanics. We investigated the influence of airway obstruction on the within-breath forced oscillation technique in smokers and chronic obstructive pulmonary disease patients and evaluated the contribution of th...