Transportation of single cell and microbubbles by phase-shift introduced to standing leaky surface acoustic waves     

Meng L  Cai F  Zhang Z  Niu L  Jin Q  Yan F  Wu J  Wang Z  Zheng H 《Biomicrofluidics》2011,5(4):44104-4410410

A microfluidic device was developed to precisely transport a single cell or multiple microbubbles by introducing phase-shifts to a standing leaky surface acoustic wave (SLSAW). The device consists of a polydimethyl-siloxane (PDMS) microchannel and two phase-tunable interdigital transducers (IDTs) for the generation of the relative phase for the pair of surface acoustic waves (SAW) propagating along the opposite directions forming a standing wave. When the SAW contacts the fluid medium inside the microchannel, some of SAW energy is coupled to the fluid and the SAW becomes the leaky surface wave. By modulating the relative phase between two IDTs, the positions of pressure nodes of the SLSAW in the microchannel change linearly resulting in the transportation of a single cell or microbubbles. The results also reveal that there is a good linear relationship between the relative phase and the displacement of a single cell or microbubbles. Furthermore, the single cell and the microbubbles can be transported over a predetermined distance continuously until they reach the targeted locations. This technique has its distinct advantages, such as precise position-manipulation, simple to implement, miniature size, and noninvasive character, which may provide an effective method for the position-manipulation of a single cell and microbubbles in many biological and biomedical applications.  相似文献   

Land reform in Zimbabwe,class dynamics and delayed Bandung: an interview with Sam Moyo     

Yan Hairong  Chen Yiyuan 《Inter-Asia Cultural Studies》2016,17(1):128-139

Interviewers’ note: Land reform in Zimbabwe has caught the world's attention. It's condemned by the mainstream in the West. It has also been highly controversial in South Africa, as post-apartheid South Africa has been unable to address the historical legacy of severe land inequality. What we find interesting and intriguing is that the land reform in Zimbabwe occurred at a time when neo-liberalism was raging in the world. What has been the historical and political context and dynamics of the land reform in Zimbabwe? Doe it bear any relationship with the earlier land reforms in some former colonial and semi-colonial countries around the mid-20th century? What are its implications for the understanding and challenging the current world system? On 19 April 2015, we had an opportunity to discuss these questions in person with Zimbabwe-based Sam Moyo, a leading agrarian political economist and a critical thinker in Africa. He was attending the Hangzhou Forum of Bandung/Third World 60 Years.  相似文献   

确立主导产业,带动城乡一体化发展——以天水市城乡统筹发展为例     

刘海蓉  王琴梅 《天水师范学院学报》2010,30(1)

从经济统筹、社会统筹和环境统筹三个方面对天水市2000～2008年城乡统筹发展的水平进行综合评价。结果表明,天水市城乡统筹发展水平每年都低于全国水平。天水市城乡统筹发展存在的问题主要表现为城乡居民人均收入差距和人均消费支出差距不断拉大,且农村居民恩格尔系数居高不下。其原因在于:全市一、二、三产业结构比例不合理;农村剩余劳动力转移缓慢;具有根植性的工业发展不足,带动作用表现不明显。为此,天水市在今后的城乡统筹发展中,应明确主导产业,带动城乡统筹发展;打造优势产业集群,建立与城市发展定位相适应的现代产业体系;促进农村剩余劳动力的转移,逐步消除城乡二元结构。  相似文献   

外语院校图书馆发展战略     

王海荣 《图书馆学刊》2010,32(7):18-21

外语院校有别于其他普通高等院校,以培养复合型的外语类人才为目标。外语院校图书馆应加强文献传递服务、文献资源的建设、译本库的建立、图书馆员队伍的建设,以及设立图书馆业务和管理咨询委员会,才能协助教学部门培养出符合社会需要的外语类人才。  相似文献   

高校教师职业倦怠与幸福感相关研究     

黄海蓉  苗元江 《科技广场》2012,(2):191-193

目的:探讨高校教师职业倦怠与幸福感的关系。方法:使用《教师职业倦怠问卷》和《综合幸福问卷》对219名高校教师进行问卷调查。结果:高校教师幸福指数得分为5.36±1.66分;高校教师职业倦怠程度较轻;职业倦怠中情感衰竭、非人性化、低成就感与幸福感各维度存在显著相关关系;多元逐步回归表明情感枯竭和低成就感对高校教师幸福感有显著影响。结论:高校教师职业倦怠与幸福感密切相关。  相似文献   

政务信息公开与现行文件开放问题探讨   总被引：1，自引：0，他引：1  

李海蓉 《档案》2007,(2)

政务信息作为一种公共信息,在人们的社会生活中发挥着越来越重要的作用。实行政务信息公开和现行文件开放利用是世界各国政治文明发展的必然趋势。早在1776年,瑞典就制定了《新闻自由法》,规定普通市民享有要求法院和行政机关公开有关公务文书的权利。1789年法国大革命中诞生的《人权宣言》,也提出了“公民有权向公务员索取文书”,1978年法国又正式制定了《行政文书公开法》。  相似文献   

塞上江南的明珠——宁夏回族自治区档案馆     

杨淑芳  张国栋  王海荣 《档案与史学》2007,(4):61-64

宁夏自古以来是内接中原,西通西域,北连大漠,各民族南来北往十分频繁的地区,是历史上东西交通贸易的重要通道.  相似文献   

创新扩散模型的研究综述   总被引：2，自引：0，他引：2  

刘超  王君祥  宋海荣 《科技管理研究》2007,27(5):125-127

自从20世纪60年代创新扩散研究引入到技术预测与销售学领域以来,创新扩散模型的研究日趋活跃,学者们对Bass模型的结构、概念假设、参数估计进行了反复检验。本文系统地对基本扩散模型、Bass模型的扩展以及参数估计方法这几个方面进行了详细的综述。  相似文献   

从内涵与外延角度理解泛函分析重要概念     

许栩  廉海荣  耿凤杰 《继续教育研究》2021,(5):138-140

泛函分析是数学专业的一门重要分析类课程,因为课程中的概念较为理论、抽象,学生在学习过程中往往难以透彻理解与准确把握.运用逻辑科学中概念的内涵与外延理论,对泛函分析课程中出现的重要概念进行深度剖析,以期帮助学生更好地理解把握.在此基础上,通过学习逻辑学中关于概念内涵与外延的定义,比照具体的数学概念,我们提出了相关的教学思考与展望,并可依照相关安排设计来开展教学课程实践,以提升课堂效果,帮助学生更好地理解、消化、吸收课程中的重要概念.  相似文献   

浅析视觉次序对平面设计信息传达的潜在引导作用     

黄海荣 《新闻界》2008,(1):140-142

本文采用具体实例分析的方式,希望通过对平面设计视觉次序与视觉语言相互关系的深入探讨,明晰在当今平面设计中必须认真思考的关于视觉次序的问题。  相似文献