矩阵变换器研究综述

矩阵变换器作为一种新型变换器,越来越引起人们的重视。矩阵变换器的关键技术主要包括:主回路的拓扑结构、安全换流技术、调制策略和保护电路设计等。通过这几个关键技术的介绍,进一步分析目前矩阵变换器的研究热点和应用前景。     

“邓小平理论课”教学实践中的若干体会

邓小平理论要做到进课堂、进教材、进头脑 ,党委要高度重视 ,具体做到位 ;其次任课教师要方法得当 ,采取理论联系实际的灵活多样方式。     

低幼儿童听力测验

早期干预能帮助弱听儿童可以更好地学习语言和沟通 ,也直接影响儿童的学习和成长。早期诊断 ,便成为早期干预的一个预先程序 ,可是要把听觉的毛病诊断出来 ,我们首先要明白如何测试不同年龄的儿童。这篇文章主要介绍了对不同年龄的低幼儿童进行行为听力测验的方法和技术     

High efficiency vortex trapping of circulating tumor cells

Circulating tumor cells (CTCs) are important biomarkers for monitoring tumor dynamics and efficacy of cancer therapy. Several technologies have been demonstrated to isolate CTCs with high efficiency but achieve a low purity from a large background of blood cells. We have previously shown the ability to enrich CTCs with high purity from large volumes of blood through selective capture in microvortices using the Vortex Chip. The device consists of a narrow channel followed by a series of expansion regions called reservoirs. Fast flow in the narrow entry channel gives rise to inertial forces, which direct larger cells into trapping vortices in the reservoirs where they remain circulating in orbits. By studying the entry and stability of particles following entry into reservoirs, we discover that channel cross sectional area plays an important role in controlling the size of trapped particles, not just the orbital trajectories. Using these design modifications, we demonstrate a new device that is able to capture a wider size range of CTCs from clinical samples, uncovering further heterogeneity. This simple biophysical method opens doors for a range of downstream interventions, including genetic analysis, cell culture, and ultimately personalized cancer therapy.     

如何淘到二手好货

正不知不觉中,"二手货"的定义早已悄悄发生了变化,这也源于人们观念的转变——曾经的二手货陈旧、单调,是旧货的代名词;而如今的二手货则被赋予了全新的概念:闲置品、奢侈品、收藏品成为了二手货市场的主力军。由于购买二手货不光省钱,而且"绿色、环保",因此这种消费方式也逐渐成为了一种时尚,影响着人们生活的方方面面。如何才能淘到二手好货?购买二手货时应该注意什么?看看我们为你提供的建议吧!