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In this article, we present a bearingless motor with a novel segmented dipole interior permanent magnet (IPM) slice rotor. The segmented dipole IPM rotor contains a unique pattern of interior permanent magnets arranged to generate a dipole air gap flux pattern. The magnets are encapsulated within an electrical steel rotor structure. The stator contains a three-phase, four-pole winding for suspension and a three-phase, two-pole winding for rotation. We present analyses of several candidate rotor designs. The analyses indicate that the segmented dipole IPM rotor achieves a reduced tradeoff between force and torque capacity and relatively symmetric force dynamics as compared to prior art designs and alternate topologies. Symmetric and decoupled force dynamics allow a simple force decoupling algorithm to be used. We designed, constructed, and tested a prototype system. We experimentally demonstrate that the prototype system can achieve stable levitation and open-loop rotation. [ABSTRACT FROM AUTHOR]

Surgical closure of patent ductus arteriosus may be more effective and less expensive than implanting an occluder device with a catheter. Patent ductus arteriosus is a birth defect characterized by an opening between the aorta and the pulmonary artery. Among 631 children treated for patent ductus arteriosus from 1982 to 1987, 185 had an occluder implanted and 446 had conventional surgical closure. The surgical closure was successful in all cases. The implant procedure was successful in only 86.5% of cases, even after some patients had further surgery. There were fewer significant complications in the surgical closure group. Average costs per patient for the procedures, including hospital care and follow-up, were $8,838 for surgical closure and $11,466 for occluder implantation. The occluder implantation involves more sophisticated and costly technology and has a lower success rate than the standard surgical closure method.

The New England Regional Infant Cardiac Program (NERICP) is a voluntary association of all hospitals in the New England states which offer definitive care for infants with heart disease. With the purpose of improving infant cardiac care, the program began in 1968 and continues to the present. Specific activities include professional education to improve case finding and earlier referral; identification and subsidy of appropriate transportation facilities; improved communication with participating hospitals; subsidy of follow-up where needed; provision for room and board for indigent parents when their baby has been moved some distance from home; and continuing nursery nurse education in the recognition of infants with heart disease. All participating hospitals agree to tabulation of their entire experience with infants with heart disease (3626 infants in 9 years). Case histories of surviving infants have been updated systematically. The period of July 1968 to June 1974 was selected for this detailed analysis because data from this period form the basis of an ongoing long-term follow-up study and have been reverified several times. This analysis is continued to the first year of life. More recent data, July 1974 to June 1977, are discussed separately and italicized numerical data from 1974 to 1977 have been added to tables where the results may be of interest. In the early years, case finding rose by 20% and has continued to increase gradually. By 1976, there were 2.4 NERICP infants per 1000 live births identifiable in the New England states. Surveys of state vital statistics showed a 50% decrease in infants who died with heart disease who did not reach a participating hospital. Neonates are admitted to participating hospitals earlier; admissions of infants less than 2 days old increased from 20% to 34% in 1977. Of infants admitted in 1977, more than 50% were in the first week of life., During the period of study from 1969 to 1974, there was a consolidation of hospital services for infants with heart disease. Of the initial 11 participating hospitals in 1969, by [...]

The clinical recognition of an intracranial arteriovenous fistula in a newborn infant depends on finding good peripheral pulses, a hyperdynamic cardiac impulse, cardiomegaly, and a cranial bruit. Dilated scalp veins and visible vascular malformations over tile head will point toward the diagnosis. Cardiac catheterization can be diagnostic through recognition of a wide pulse pressure in combination with high oxygen saturations in the jugular veins and the right heart chambers. Cerebral angiography provides required anatomic detail. Surgical clipping of the feeding arteries may be helpful and even curative. Pediatrics, 49:30, 1972, PULMONARY ARTERY HYPERTENSION, CARDIAC CATHETERIZATION, CENTRAL NERVOUS SYSTEM MALFORMATIONS, CRANIAL BRUIT NEWBORN INFANT. [ABSTRACT FROM AUTHOR]

Discusses the practice in regard to diagnosis or therapy of congenital disease of newborn infants. Concepts that are recognizable as rationalizations of the physician's inability to provide appropriate diagnostic work-up and surgery; Health condition of an infant with severe congestive heart failure; Useful observation in the infant with heart disease.