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Considering the transient squeezing motion, the magneto-hydrodynamic (MHD) steady and dynamic characteristics of one-dimensional slider bearings lubricated with an electrically conducting fluid in the consideration of a transverse magnetic field are numerically investigated. Using the MHD motion equations and, the continuity equation, we have derived a MHD dynamic Reynolds-type equation, which is applicable to slider bearings taking into account the squeezing effect ∂h/∂t, in which the general film-shape function is described by h = h(x, t). A closed-formsolution for the pressure of an inclined-plane slider is obtained and applied to predict theMHDdynamic stiffness and damping characteristics of bearings. According to the results obtained, the application of externally applied magnetic fields signifies an apparent increase in the MHD steady film pressure. Comparing with the classical non-conducting-lubricant case, the applied magnetic-field effects characterized by the Hartmann number provide significant improvement in the MHD steady load-carrying capacity, the MHD dynamic stiffness coefficient, and the MHD dynamic damping coefficient. The improvement of dynamic characteristics of MHD bearings is more pronounced with large Hartmann numbers and small minimum film thicknesses. For guiding the use of the present study, a design example is illustrated. Further results shown in the tables are provided for engineering application. [ABSTRACT FROM AUTHOR]

Right atrial isomerism or left atrial isomerism is frequently diagnosed as situs ambiguous without further discrimination of the specific morbid anatomy. Thirty six cases of right atrial isomerism and seven cases of left atrial isomerism were collected from the records and pathological museum at the National Taiwan University Hospital. There was a necropsy report for 18 cases. In all patients one or more of the following conditions was met: (a) isomeric bronchial anatomy, (b) echocardiographic and angiocardiographic evidence of isomerism, and (c) surgical or necropsy evidence of abnormal atrial anatomy. An anomalous pulmonary venous connection was present in 55% of patients with right atrial isomerism; in left atrial isomerism one case (14%) had a partial anomalous pulmonary venous connection. Forty per cent of cases of anomalous pulmonary venous connection with right atrial isomerism had obstruction. Six (86%) of seven cases with left atrial isomerism had an ambiguous biventricular atrioventricular connection. In contrast, univentricular atrioventricular connection (26 of 36, 72%) was significantly more common in right atrial isomerism. A common atrioventricular valve was the most frequent mode of connection in both forms. Two discrete atrioventricular valves were significantly more common in left atrial isomerism. Atrioventricular valve regurgitation was detected in 14 cases. Double outlet right ventricle was the most common type of ventriculoarterial connection. The most commonly cited causes of death after either palliative or definitive operation were undetected anomalous pulmonary venous connection, pulmonary venous stricture, and uncorrected atrioventricular valve or aortic regurgitation complicated by abnormal coagulation. Although the prognosis is poor, successful operation depends on knowledge of the precise anatomical arrangement associated with atrial isomerism. [ABSTRACT FROM PUBLISHER]