In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without ...In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms.展开更多
A 19-year-old woman with a bicuspid aortic valve was admitted because of active infective endocarditis with a root abscess. Four weeks of antibiotic therapy achieved negative blood cultures and normalized inflammatory...A 19-year-old woman with a bicuspid aortic valve was admitted because of active infective endocarditis with a root abscess. Four weeks of antibiotic therapy achieved negative blood cultures and normalized inflammatory signs;however, echocardiography revealed severe aortic regurgitation through an abscess cavity located at the root. The modified Ross procedure, in which the pulmonary autograft was reinforced with a prosthetic graft to prevent postoperative annular dilation, was successfully performed. The postoperative clinical course was uneventful, and echocardiography performed at 1 year showed trivial aortic regurgitation. Selection of homograft may benefit young woman who wishes to bear children, and covering pulmonary autograft by a prosthetic graft in order to prevent annular dilatation of autograft in patient with bicuspid aortic valve, may be allowed only under negative infection sign.展开更多
文摘In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms.
文摘A 19-year-old woman with a bicuspid aortic valve was admitted because of active infective endocarditis with a root abscess. Four weeks of antibiotic therapy achieved negative blood cultures and normalized inflammatory signs;however, echocardiography revealed severe aortic regurgitation through an abscess cavity located at the root. The modified Ross procedure, in which the pulmonary autograft was reinforced with a prosthetic graft to prevent postoperative annular dilation, was successfully performed. The postoperative clinical course was uneventful, and echocardiography performed at 1 year showed trivial aortic regurgitation. Selection of homograft may benefit young woman who wishes to bear children, and covering pulmonary autograft by a prosthetic graft in order to prevent annular dilatation of autograft in patient with bicuspid aortic valve, may be allowed only under negative infection sign.
