Background: Heart valve diseases are considered a common disease in human and animals, and valve replacement is an option for treatment of valvular diseases. Objectives: In this study efficacy of a tissue engineered valve in thoracic aorta was evaluated with transthoracic echocardiography. Methods: This study was undertaken on 6 male sheep. Echocardiography was performed on all sheep 24 hours b...

there is a paucity of literature regarding iatrogenic aortic valve perforation after cardiac operation is performed in the vicinity of the aortic valve. this report describes the clinical, echocardiographic, and angiocardiographic recognition of iatrogenic aortic valve perforation in a patient who had previously under gone membranous ventricular septal defect and pulmonary stenosis. five days a...

since knowledge on hydrodynamic torque of a butterfly valve is very important for butterfly valve design, its hydrodynamic torque is investigated in this paper. in reality, the investigation of the loss coefficient and torque from some experiments will take a long time and a lot of money. this paper presents a statistical study of the flow past the butterfly valve in a static analysis using com...

A study is made of the propagation of Rossby waves in a stably stratified shear flows. The wave equation for the Rossby waves is derived in an isothermal atmosphere on a beta plane in the presence of a latitudinally sheared zonal flow. It is shown that the wave equation is singular at five critical levels, but the wave absorption takes place only at the two levels where the local relative frequ...

recently, there have been more reports of cardiac valve infections due to the increasing number of intravenous (iv) drug abusers and chronic renal failure patients. among cardiac valves, tricuspid valve is most commonly affected in the course of endocarditis. appropriate management of these patients is a challenging and controversial issue in the field of cardiac surgery. treatment options in s...

Introduction:  In patients who underwent surgery to repair Tetralogy of Fallot, right ventricular dilation from pulmonary regurgitation may be result in right ventricular failure, arrhythmias and cardiac arrest. Hence, pulmonary valve replacement may be necessary to reduce right ventricular volume overload. The aim of present study was to assess the effects of pulmonary valve replacement on rig...

‎We study dual integral equations which appear in formulation of the‎ ‎potential distribution of an electrified plate with mixed boundary‎ ‎conditions‎. ‎These equations will be converted to a system of‎ ‎singular integral equations with Cauchy type kernels‎. ‎Using‎ ‎Chebyshev polynomials‎, ‎we propose a method to approximate the‎ ‎solution of Cauchy type singular integral equation which will ...

In this paper, some elementary operations on triangular fuzzynumbers (TFNs) are defined. We also define some operations on triangularfuzzy matrices (TFMs) such as trace and triangular fuzzy determinant(TFD). Using elementary operations, some important properties of TFMs arepresented. The concept of adjoints on TFM is discussed and some of theirproperties are. Some special types of TFMs (e.g. pu...

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