电源应用集成功率半导体器件

ISOPLUS 14IM系列功率半导体器件提供的性能使其非常适合开关模式电源(SMPS)应用:集成度高、工作特性可针对高开关频率优化、集成隔离/绝缘措施可以简化安装,此外对于高电压应用如果需要的话还可提供较大的防放电和漏电间隔。本文详细介绍了这些器件所使用的技术,并特别针对开关电源应用讨论了其特性。     

Effect of bed height and use of hands on trunk angular velocity during the sit-to-stand transfer

The ability to rise from a chair or bed is critical to an individual's quality of life because it determines functional independence. This study was to investigate the effect of bed height and use of hands on trunk angular velocity and trunk angles during the sit-to-stand (STS) performance. Twenty-four older persons (median age 74 years) were equipped with a body-fixed gyroscopic sensor and stood up from a bed adjusted to different heights, with and without the use of hands at each height. Peak angular velocity and trunk range of motion decreased with increasing bed height (all p ≤ 0.038) and were lower using hands during STS transfer indicating less effort. In conclusion, gyroscopic sensor data of the STS transfer of older persons show differences as an effect of bed height and use of hands. These results provide the rationale for recommending a relatively high bed height for most of the older persons.     

Erteilte ausländische Patente

Ohne Zusammenfassung     

High hydrogen content super-lightweight intermetallics from the Li–Mg–Si system

The existence of Li-rich super-lightweight intermetallics in the Li–Mg–Si ternary system has attracted attention for high capacity hydrogen storage materials. The hydrogenation properties of the alloys were studied by thermogravimetric analysis, differential scanning calorimetry in H₂ atmosphere and X-ray diffraction. The Li-rich alloy absorbs the highest amount of hydrogen (8.8% w/w for Li₇₀Mg₁₀Si₂₀), while the Mg-rich alloy (Li₃₀Mg₄₀Si₃₀) absorbs 6.0% w/w H₂ and shows the first experimental evidence for LiMgH₃ formation with LiNbO₃-type structure during hydrogenation.     

Increased platelet sensitivity toward platelet inhibitors during physical exercise in patients with coronary artery disease

Generalized atherosclerosis and coronary artery disease (CAD) are associated with endothelial dysfunction and during acute myocardial ischemia platelet activation has been reported. Activated platelets exert activated fibrinogen receptors (GP IIb/IIIa) and express CD 62p being regarded as reliable marker for platelet activation. Patients with angiographically proven CAD performed a bicycle exercise test until the onset of angina or ST-segment depression. We studied the ischemia-induced alterations in fibrinogen binding to activated platelet GP IIb/IIIa receptors and CD 62p expression. Therefore, the basal fibrinogen binding to GP IIb/IIIa and CD 62p expression and the thrombin-concentration for half-maximal platelet activation before and after exercise testing were determined. Additionally, inhibition of thrombin-induced platelet activation by increasing concentrations of the prostacyclin-analog iloprost and the NO-donor SIN-1 was examined. In patients with CAD, a significantly reduced basal activation and a highly significant reduction in sensitivity towards thrombin was measured. The thrombin-induced expression of GP IIb/IIIa and CD 62p was significantly diminished in patients with CAD after physical exercise and their platelets were significantly more sensitive towards the inhibitory effects of iloprost and SIN-1. These data demonstrate a significant reduction in platelet activation in response to physical exercise in patients with CAD and advanced atherosclerosis. Despite exercise induced myocardial ischemia as evidenced by angina and ECG-changes, the platelets are not generally activated, as it could be expected. Thus, patients with myocardial ischemia experienced a reduced platelet activity and enhanced sensitivity towards prostacyclin (PGI2) and nitric oxide, probably due to an augmented release of endogenous platelet inhibitory mediators.