This research has successfully developed an advance d manufacturing system for 300mm silicon wafer,using fixed abrasive instead o f conventional free slurry,to provide a totally integrated solution for achievi ng the ...This research has successfully developed an advance d manufacturing system for 300mm silicon wafer,using fixed abrasive instead o f conventional free slurry,to provide a totally integrated solution for achievi ng the surface roughness Ra<1 nm(Ry<5～6 nm) and the global flatness<O.2μm /300 mm.In addition to high throughput rate,this system significantly reduc es the total energy consumption by 70%,compared with the current process used for 200mm Si wafer.This paper describes the principle of material removal,st ate-of-the-art technologies and kinematical analysis for one-stop finishing o f 300mm Si wafer by fixed abrasive process.展开更多
Introduction: Knowledge of the risks of pregnancy with heart disease is important because the maternal mortality is much higher than the average. Peripartum cardiomyopathy (PPCM) is rare but it is one of major causes ...Introduction: Knowledge of the risks of pregnancy with heart disease is important because the maternal mortality is much higher than the average. Peripartum cardiomyopathy (PPCM) is rare but it is one of major causes of maternal death. We experienced a pregnant patient with severe aortic regurgitation (AR) presented symptoms of acute heart failure. Her heart failure was not better after an emergency cesarean section and aortic valve replacement (AVR) therefore we think that PPCM caused her heart failure. Case presentation: A 35-year-old woman diagnosed as having severe AR became pregnant. No changes in the AR were apparent during pregnancy. However, the patient developed symptoms of acute heart failure at 37 weeks of gestation, and an emergency cesarean section was performed under general anesthesia. Her hemodynamic status worsened after the cesarean section, and AVR was performed. She was supported with percutaneous cardiopulmonary support (PCPS) after the operation. As recovery seemed to take longer than usual, we decided to implant a ventricular assist device (VAD). Her condition improved after VAD placement, but then she died from a cerebral infarction. In this case, the heart failure was an acute-onset even though AR was stable before and after the pregnancy, and the heart failure did not improve after AVR. Therefore, we concluded that PPCM, rather than AR caused her heart failure. Conclusions: We encountered a case of a pregnant patient with severe AR who presented with symptoms of acute heart failure caused by PPCM. The effect of AR to her heart failure could not be easily denied. This delayed the diagnosis of PPCM, which in turn delayed our decision to use a VAD. Therefore, PPCM should be considered when pregnant patients with heart disease present symptoms of heart failure.展开更多
文摘This research has successfully developed an advance d manufacturing system for 300mm silicon wafer,using fixed abrasive instead o f conventional free slurry,to provide a totally integrated solution for achievi ng the surface roughness Ra<1 nm(Ry<5～6 nm) and the global flatness<O.2μm /300 mm.In addition to high throughput rate,this system significantly reduc es the total energy consumption by 70%,compared with the current process used for 200mm Si wafer.This paper describes the principle of material removal,st ate-of-the-art technologies and kinematical analysis for one-stop finishing o f 300mm Si wafer by fixed abrasive process.
文摘Introduction: Knowledge of the risks of pregnancy with heart disease is important because the maternal mortality is much higher than the average. Peripartum cardiomyopathy (PPCM) is rare but it is one of major causes of maternal death. We experienced a pregnant patient with severe aortic regurgitation (AR) presented symptoms of acute heart failure. Her heart failure was not better after an emergency cesarean section and aortic valve replacement (AVR) therefore we think that PPCM caused her heart failure. Case presentation: A 35-year-old woman diagnosed as having severe AR became pregnant. No changes in the AR were apparent during pregnancy. However, the patient developed symptoms of acute heart failure at 37 weeks of gestation, and an emergency cesarean section was performed under general anesthesia. Her hemodynamic status worsened after the cesarean section, and AVR was performed. She was supported with percutaneous cardiopulmonary support (PCPS) after the operation. As recovery seemed to take longer than usual, we decided to implant a ventricular assist device (VAD). Her condition improved after VAD placement, but then she died from a cerebral infarction. In this case, the heart failure was an acute-onset even though AR was stable before and after the pregnancy, and the heart failure did not improve after AVR. Therefore, we concluded that PPCM, rather than AR caused her heart failure. Conclusions: We encountered a case of a pregnant patient with severe AR who presented with symptoms of acute heart failure caused by PPCM. The effect of AR to her heart failure could not be easily denied. This delayed the diagnosis of PPCM, which in turn delayed our decision to use a VAD. Therefore, PPCM should be considered when pregnant patients with heart disease present symptoms of heart failure.
