We developed and validated a mitral valve orifice method for Doppler cardiac output determination. In 15 open-chest dogs, cardiac output was controlled and measured by a roller pump interposed between the right atrium and pulmonary artery as a right-heart bypass. Left heart flows were measured in the open-chest dog model by Doppler measurements at the mitral valve orifice and compared not only ...

AIMS To determine whether mitral annular calcification and aortic valve calcification, with or without stenosis, are expressions of atherosclerotic disease. METHODS The incidence of atherosclerotic risk factors was analysed in patients with mitral annular calcification and aortic valve calcification and in control patients from a prospective echocardiographic database of 8160 consecutive pati...

Background and Purpose: Candida endocarditis is an infrequent disease with a high mortality rate, which commonly occurs in immunosuppressed patients with cardiac valve replacement. We reported a 70-year-old woman diagnosed with Candida prosthetic valve endocarditis (PVE). This study also involved a review of all published cases of Candida PVE from 1970. Case report: Herein, we reported a 70-ye...

the usage of turbochargers in diesel engines has led to the downsizing of the motors as well as usage of the waste gates in turbochargers. any dimensional reduction in turbochargers and appurtenant leads to an enhancement on the performance of internal combustion engines and in environmental problems in terms of aerodynamic, thermodynamic and mechanical specifications for both engines and turbo...

A numerical optimization methodology is applied to improve the design of a microchannel structure used in a valveless micropump. The flow simulation algorithm employs the control volume method for Cartesian grids, while advanced numerical techniques are implemented for automatic generation of unstructured, adaptively refined grids and for the representation of irregular boundaries. Several geom...

Homogeneous charge compression ignition (HCCI) seems to be the most promising solution for gasoline engines in the light of future emissions regulations. This novel combustion technique allows for significant reduction of fuel consumption and engine-out NOX emissions at low and medium engine load/speed conditions. High heat release rate enables realization of the Otto cycle close to ideal, incr...

OBJECTIVE Identification of risk factors for cardiac surgery can improve surgical results. Our aim is to identify factors related to increased hospital mortality for patients who underwent mechanical cardiac prosthesis implant. METHODS Prospective study with retrospective data acquirement study including 335 consecutive patients who underwent at least one implant of St. Jude Medical mechanica...

This paper proposes a method of evaluating the fatigue life of a refrigeration compressor reed valve, given the applied stresses as might be computed by a valve simulation. Mean and alternating values of equivalent stresses (e.g. Von Mises) are plotted in the Haigh diagram. Various choices of models are considered for the safe area of the diagram. This method takes into account surface finish, ...

BACKGROUND A bicuspid aortic valve (BAV) is associated with premature valve dysfunction and abnormalities of the ascending aorta. The aim of our study was to assess the degree of ascending aortic dilatation by measuring the ratio of the dimension of the AAo to that of the descending aorta (DAo) using preoperative computerized tomography (CT). METHODS A review of our institutional clinical dat...

Operator performance during the expiratory phase of manual hyperinflation appears to vary between physiotherapists for Mapleson-B or C circuits. Some physiotherapists release the valve but maintain compression of the bag, whereas others release both the valve and the bag. The effect of this difference on peak expiratory flow rate (PEFR) has not been reported. The aim of this study was to docume...