Two-dimensional numerical simulations are used to explore the mechanism for asymmetric deflection of the glottal jet during phonation. The model employs the full Navier-Stokes equations for the flow but a simple laryngeal geometry and vocal-fold motion. The study focuses on the effect of Reynolds number and glottal opening angle with a particular emphasis on examining the importance of the so-c...

BACKGROUND We evaluated the hemodynamic status of patent ductus arteriosus (PDA) by measuring vena contracta width (VCW) and effective shunt orifice area (ESOA) using proximal isovelocity surface area (PISA) on color Doppler imaging. METHODS AND RESULTS: Study subjects were 21 patients with PDA (mean age, 3.6 years). We measured VCW (mm/m(2)) and ESOA (cm(2)) by the PISA method using echocardio...

abstract in the present article, effective parameters of the buoyant jets have been evaluated in the stagnant ambient fluid. the jet parameters, geometry parameters and environmental parameters are investigated. using dimensional analysis, a set of dimensionless functions was obtained. to achieve the exact functions, a physical model was built in the hydraulic laboratory of shahid chamran unive...

The transitional Reynolds numbers for different patterns are available and a proposed transitional map is also provided in this paper. The transition of falling-films on flat tubes is studied in this work. Water and ethylene glycol are used as working fluids, for falling-film experiments conducted under adiabatic conditions, without an imposed vapor flow. The flow patterns are recorded using a ...

The formation and evolution of 3D synthetic jets is examined using direct numerical simulations. The primary focus of the current study is on examining the formation of 3D synthetic jets and the effect of changes in the jet aspect-ratio on the flow produced by the jet. Jets in quiescent and cross-flow cases are investigated. The study compares the vortex dynamics, velocity profiles and the othe...

A 56-year-old male patient presented with an isolated posterior mitral leaflet (PML) prolapse due to degenerative mitral valve (MV) disease. The preoperative transthoracic echocardiography showed severe mitral regurgitation (MR) due to a flail P2 segment. Echocardiographic examination revealed a normal left ventricular ejection fraction of 67%, the mitral annulus with a diameter of 39 mm and no...

OBJECTIVE To measure caval and pulmonary flows at rest and immediately after exercise in patients with total cavopulmonary connection (TCPC). DESIGN An observational study using the patients as their own controls. SETTING Using a combination of magnetic resonance (MR) phase contrast techniques and an MR compatible bicycle ergometer, blood flow was measured in the superior vena cava, the tun...

Objective: To measure caval and pulmonary flows at rest and immediately after exercise in patients with total cavopulmonary connection (TCPC). Design: An observational study using the patients as their own controls. Setting: Using a combination of magnetic resonance (MR) phase contrast techniques and an MR compatible bicycle ergometer, blood flow was measured in the superior vena cava, the tunn...

A 61-year-old female patient presented with isolated pos ter ior mi t ra l l ea f l e t (PML) pro lapse due to degenerative mitral valve (MV). Preoperative transthoracic echocardiography confirmed severe mitral regurgitation (MR) and isolated prolapse of the P2 segment. The patient was in New York Heart Association (NYHA) functional class II to III. Her left ventricular function was good with a...