in recent socio-economic state it is not possible to have different sets of prosthetic cardiac valves available in the operating room before open-heart surgery for valvular replacement. in this study the diameter of the aortic valve ring measured in 2-d echocardiography was compared with the size of the aortic prosthetic valves implanted for the patients with aortic valvular disease. the purpos...

a computational optimization was performed for a direct-injection diesel engine using three-dimensional modeling. fully transient cfd analyses of different valve profile strategies for the intake and compression strokes were performed to evaluate the effects on both engine performance and in-cylinder flow-field evolution. the turbulence model was used along with the second order linear upwind s...

background: one of the most important post-operation problems encountered with hepaticojejunostomy (kasai operation) in patients with biliary atresia is cholangitis. the aim of this study was to evaluate the efficiency of anti-reflux valve in decreasing the incidence of cholangitis after hepaticojejunostomy.   methods: ten dogs were randomly divided into two groups of equal size. in group a rou...

background: posterior urethral valve presenting in adulthood is uncommon. this can be an unusual cause of primary male infertility as a result of abnormalities in sexual function. case presentation: this report describes a 40 year old man who presented to us on account of inability to impregnate his wife after 2 years of marriage. history revealed poor stream of urine since childhood and passag...

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...

Objective(s): Tissue engineering represents a new approach to solve the current complications of the heart valve replacements by offering viable valve prosthesis with growth and remodeling capability. In this project, electrospinning and dip coating techniques were used to fabricate heart valve constructs from medical grade polyurethane (PU). Methods: Fir...

In this study it has been tried, to compare results and convergence rate of sensitivity analysis and conjugate gradient algorithms to reduce fuel consumption and increasing engine performance by optimizing the timing of opening and closing valves in XU7/L3 engine. In this study, considering the strength and accuracy of simulation GT-POWER software in researches on the internal combustion engine...

The study on the flow behave inside of a ball valve is important for heavy crude oil transportation. Owe to the fast progress of the numerical technique, it becomes an effective way to observe the flows inside a valve and to analyze the flow structure of the oil-water core annular flow. In the present study, the simulation of the oil-water core annular flowing through the valve is conducted...

global myocardial ischemia and ischemia-reperfusion injury are potential adverse events related with cardioplegic arrest. beating heart surgery has avoided such complications and adapted to valve surgery following successful results published on myocardial revascularization. difficulty in weaning from cardiopulmonary bypass may be lessened by using on-pump beating heart surgery for mitral valve...