Stem cells in microfluidics     

Wu HW  Lin CC  Lee GB 《Biomicrofluidics》2011,5(1):13401

Microfluidic techniques have been recently developed for cell-based assays. In microfluidic systems, the objective is for these microenvironments to mimic in vivo surroundings. With advantageous characteristics such as optical transparency and the capability for automating protocols, different types of cells can be cultured, screened, and monitored in real time to systematically investigate their morphology and functions under well-controlled microenvironments in response to various stimuli. Recently, the study of stem cells using microfluidic platforms has attracted considerable interest. Even though stem cells have been studied extensively using bench-top systems, an understanding of their behavior in in vivo-like microenvironments which stimulate cell proliferation and differentiation is still lacking. In this paper, recent cell studies using microfluidic systems are first introduced. The various miniature systems for cell culture, sorting and isolation, and stimulation are then systematically reviewed. The main focus of this review is on papers published in recent years studying stem cells by using microfluidic technology. This review aims to provide experts in microfluidics an overview of various microfluidic systems for stem cell research.  相似文献   

On-demand electrostatic droplet charging and sorting     

Ahn B  Lee K  Panchapakesan R  Oh KW 《Biomicrofluidics》2011,5(2):24113

This study reports a droplet-based microfluidic device for on-demand electrostatic droplet charging and sorting. This device combines two independent modules: one is a hydrodynamic flow focusing structure to generate water-in-oil droplets, and the other is the two paired-electrodes for charging and sorting of the droplets. Depending on the polarity on charging electrodes, water-in-oil droplets can be electrostatically charged positively or negatively, followed by automatic real-time electric sorting. This approach will be useful when preformed droplets, with a positive, a negative, or with no charge, need to be manipulated for further on-chip droplet manipulation.  相似文献   

Bromo-oxidation reaction in enzyme-entrapped alginate hollow microfibers     

Asthana A  Lee KH  Shin SJ  Perumal J  Butler L  Lee SH  Kim DP 《Biomicrofluidics》2011,5(2):24117

In this article, the authors present the fabrication of an enzyme-entrapped alginate hollow fiber using a microfluidic device. Further use of enzyme-entrapped alginate hollow fibers as a biocatalytic microchemical reactor for chemical synthesis is also deliberated in this article. To ensure that there is no enzyme leaching from the fiber, fiber surfaces were coated with chitosan. To confine the mobility of reactants and products within the porous hollow fibers the entire fibers were embedded into a transparent polydimethylsiloxane (PDMS) matrix which also works as a support matrix. A vanadium-containing bromoperoxidase enzyme isolated from Corallina confusa was used as a model enzyme to demonstrate the use of these alginate hollow-fiber reactors in bromo-oxidation of phenol red to bromophenol blue at different dye flow rates. Stability of the entrapped enzyme at different temperatures and the effect of the chitosan coating on the reaction conversion were also studied. It was observed that molecules as big as 27 kDa can be retained in the matrix after coating with chitosan while molecules with molecular-weight of around 378 Da can still diffuse in and out of the matrix. The kinetic conversion rate in this microfluidic bioreactor was more than 41-fold faster when compared with the standard test-tube procedure.  相似文献   

Energy Performance and Condensation Risk of DCDV System in Subtropical Hong Kong简     

贾捷  李慧玲 《天津大学学报(英文版)》2014,20(1):42-47

The combined use of dry cooling （DC） system and dedicated ventilation （DV） system to decouple cool-ing and dehumidification process for energy efficiency was proposed for subtropical climates like Hong Kong. In this study, the energy performance and condensation risk of the use of DCDV system were examined by analyzing its ap-plication in a typical office building in Hong Kong. Through hour-by-hour simulation using actual equipment per-formance data and realistic building and system characteristics, it was found that with the use of DCDV system, the annual energy consumption could be reduced by 54%in comparison with the conventional system （constant air vol-ume with reheat system）. In respect of condensation risk, it was found that the annual frequency of occurrence of con-densation on DC coil was 35 h. Additional simulations were conducted to examine the influence of different parame-ters on the condensation risk of DCDV system. Measures to ensure condensate-free on DC coil were also discussed.  相似文献   

《终身教育法》修正后韩国终身教育振兴政策的动向及特征     

李正连韩  王国辉 《现代远程教育研究》2014,(1):49-54,112

近10年来,从终身教育的立法到各项政策的推广实施,韩国终身教育领域出现了前所未有的变化。2007年修正的韩国《终身教育法》的公布不仅明确了终身教育的范围,而且也使中央与地方的职责与权限更加明确,并通过重组力图建构更加完善且有效率的终身教育行政与财政支援体制。为了振兴终身教育,韩国大力开展了相应的支援计划：终身学习城市支援计划;终身学习账户制度;终身学习中心大学培育计划;终身教育专业人员的培养及其能力提升计划等。呈现的特点：一是国家相关政策的制定与引导是推进终身教育的根本动力．足够的经费和人力资源支撑是必要条件。二是注重整合各类教育资源,特别是在建立多样的终身教育机构和设施等平台的同时,也注重发挥学校教育的作用。三是实施面向全员并开展全程的终身教育,特别注重增加弱势群体的教育机会。这次修正不仅促进了各自治团体终身教育基础设施的建设,提升了社区网络的发展水平,而且还建立了将学习成果运用于地方的循环体系,促进了国民对终身教育的理解及参与,推动了韩国社会的协调发展。  相似文献   

Correction to: The State of Current Reading Intervention Research for English Learners in Grades K–2: a Best-Evidence Synthesis     

Roberts  Garrett J.  Hall  Colby  Cho  Eunsoo  Coté  Brooke  Lee  Jihyun  Qi  Bingxin  Van Ooyik  Jacklyn 《Educational Psychology Review》2022,34(1):473-473

Educational Psychology Review -  相似文献   

Impacts of an AI-based chabot on college students’ after-class review,academic performance,self-efficacy,learning attitude,and motivation     

Lee  Yen-Fen  Hwang  Gwo-Jen  Chen  Pei-Ying 《Educational technology research and development : ETR & D》2022,70(5):1843-1865

Educational technology research and development - Review strategies after learning new knowledge are essential for students to consolidate the key points, understand the subject content, analyze...  相似文献   

Identifying the Content,Lesson Structure,and Data Use Within Pre-collegiate Data Science Curricula     

Lee  Victor R.  Delaney  Victoria 《Journal of Science Education and Technology》2022,31(1):81-98

Journal of Science Education and Technology - As data become more available and integrated into daily life, there has been growing interest in developing data science curricula for youth in...  相似文献   

The State of Current Reading Intervention Research for English Learners in Grades K–2: a Best-Evidence Synthesis     

Roberts  Garrett J.  Hall  Colby  Cho  Eunsoo  Cot&#;  Brooke  Lee  Jihyun  Qi  Bingxin  Van Ooyik  Jacklyn 《Educational Psychology Review》2022,34(1):335-361

Educational Psychology Review - This best-evidence synthesis reviews the past 20 years of rigorous reading intervention research to identify effective programs of instruction for Grade K–3...  相似文献   

The effect of design education using virtual reality-based coding on student competence and educational satisfaction     

Shim  Hyoyoung  Lee  Hyangeun 《Education and Information Technologies》2022,27(4):4577-4597

Education and Information Technologies - Virtual reality (VR) technology is playing a crucial role in the changing paradigm of education. In many cases, however, VR technology is not being taught...  相似文献