OBJECTIVES Proper valve selection is critical to ensure appropriate valve replacement for patients, because implantation of a small valve might place the patient at risk for persistent gradients. Labeled valve size is not the same as millimeter measure of prosthetic valve diameters or the annulus into which it will fit. Studies that use the labeled valve size in lieu of actual measured diameter...

The new geometrical design of stand-pipe air distributor for the combustion of the municipal solid waste was presented. The new design of the air distributors enables penetration of incombustible and unburnt carbon through opening between the air distributors, thus providing easy maintenance work. The fluidized bed experimental rig was constructed using Perspex column in which air was supplied ...

The flow field generated by a zero-net mass-flux (ZNMF) actuator is investigated via both numerical simulations and experiments to augment the current understanding of the flow physics of the orifice. The results aid in improving the accuracy of low dimensional lumped element ZNMF models suitable for design. Dimensional analysis yields a number of key parameters that govern the characteristics ...

A quantitative assessment of mitral valve orifice area can be achieved in patients with pure mitral stenosis by cardiac catheterization. In the presence of mitral regurgitation, however, accurate measurement often is impossible because total diastolic flow through the mitral valve frequently is unknow. Using a recently developed real-time, two-dimensional echocardiography system, we are able to...

Background and aims: The appendix may be involved in ulcerative colitis (UC) to variable extent. Clinical significance of appendicular involvement is not clear and it has long been considered an innocent bystander. This study prospectively investigated appendiceal histology and its clinical significance in patients with UC. Materials and methods: Colonoscopy was performed in 60 patients and bio...

Spatial appreciation of flow velocities using Doppler color flow mapping has led to quantitative evaluation of the zone of flow convergence proximal to a regurgitant orifice. Based on the theory of conservation of mass, geometric analysis, assuming a series of hemispheric shells of increasing velocity as flow converges on the orifice--the so-called proximal isovelocity surface area (PISA) effec...

BACKGROUND The reported incidence of transient neurological symptoms (TNS) after subarachnoid lidocaine administration is as high as 40%. We designed this clinical trial to determine the incidence of TNS with two different pencil-point spinal needles: one-orifice (Atraucan) and two-orifice (Eldor) spinal needles. METHODS Ninety-nine ASA physical status I or II patients undergoing surgical pro...

Measurement of permeability of cigarette envelope papers used in Low Ignition Propensity (LIP) cigarettes presents a number of practical problems:  Measurements must be made on both the conventional and low permeability band regions.  The low permeability band must be measured using a small orifice (15 x 2 mm compared to the normal 20 x 10 mm) with a flow as low as 1 ml/minute.  Leakage from...

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...