This paper investigates the thermal fluid-flow transport phenomena in an axially rotating passage in which twin concentric orifices of different radii are installed. Emphasis is placed on the effects of pipe rotation and orifice configuration on the flow and thermal fields, i.e. both the formation of vena contracta and the heattransfer performance behind each orifice. The governing equations ar...

Background- Multiple echocardiographic parameters have been identified to predict the severity of aortic regurgitation (AR) with variable reliability. This study was performed to identify which echocardiographic parameters best predict the severity of AR in a cohort of patients with congenital heart disease, using cardiovascular MRI quantification as a reference standard. Methods and Results- T...

OBJECTIVE We sought to evaluate the vena contracta width (VCW) measured using color Doppler as an index of severity of tricuspid regurgitation (TR). BACKGROUND The VCW is a reliable measure of mitral and aortic regurgitation, but its value in measuring TR is uncertain. METHODS In 71 consecutive patients with TR, the VCW was prospectively measured using color Doppler and compared with the re...

Recent papers have reported results on the numerical solution of nonlinear free boundary problems wherein a conformai transformation (which must be determined) maps the unknown flow region onto a known domain; the boundary conditions are handled by the method of steepest descent. The present paper discusses the use of the reflection property of solutions of elliptic equations to determine these...

PURPOSE The aim of this study was to evaluate the reliability of mitral regurgitation color M-mode regurgitant flow propagation velocity (RFPV) in grading mitral regurgitation (MR). METHODS We prospectively examined 52 consecutive patients with grades of MR mild in 10 patients, moderate in 19 patients, and severe in 23 patients with quantitative pulse Doppler echocardiography. MR was evaluate...

OBJECTIVES The aim of this study was to evaluate feasibility and accuracy of real-time 3-dimensional (3D) echocardiography for quantification of mitral regurgitation (MR), in a head-to-head comparison with velocity-encoded cardiac magnetic resonance (VE-CMR). BACKGROUND Accurate grading of MR severity is crucial for appropriate patient management but remains challenging. VE-CMR with 3D three-...

Most single-reed woodwind instrument models rely on a quasistationary approximation to describe the relationship between the volume flow and the pressure difference across the reed channel. Semiempirical models based on the quasistationary approximation are very useful in explaining the fundamental characteristics of this family of instruments such as self-sustained oscillations and threshold o...