Effective cell collection method using collagenase and ultrasonic vibration     

Y. Kurashina  K. Takemura  S. Miyata  J. Komotori  T. Koyama 《Biomicrofluidics》2014,8(5)

This study proposes a novel cell collection method based on collagenase treatment and ultrasonic vibration. The method collects calf chondrocytes from a reusable metal cell culture substrate. To develop our concept, we calculated the natural vibration modes of the cell culture substrate by a finite element method, and conducted eigenvalue and piezoelectric-structural analyses. Selecting the first out-of-plane vibration mode of the substrate, which has a single nodal circle, we designed and fabricated the cell collection device. The excited vibration mode properly realized our intentions. We then evaluated the cell collection ratio and the growth response, and observed the morphology of the collected cells. The collagenase and ultrasonic vibration treatment collected comparable numbers of cells to conventional trypsin and pipetting treatment, but improved the proliferating cell statistics. Morphological observations revealed that the membranes of cells collected by the proposed method remain intact; consequently, the cells are larger and rougher than cells collected by the conventional method. Therefore, we present a promising cell collection method for adhesive cell culturing process.  相似文献   

认知心理学视域下体育教学方法分类模式的创新及重构*     

祝〓娅  黄依柱 《广州体育学院学报》2014,(5):46-49

通过文献资料、逻辑分析等方法对我国体育教学方法分类体系进行研究,旨在构建以认知心理学知识观为分类标准的体育教学方法分类模式。研究表明:现有体育教学方法分类模式不能为体育教学实践提供足够的支持,运用认知心理学关于知识表征类型的相关研究成果对体育教学目标进行解构,构建了言语图表信息类教学方法、智慧技能类教学方法、认知策略类教学方法和信念类教学方法四级分类模式。该分类模式对促进体育教学方法分类研究的科学化和体育教师合理选择与运用教学方法具有重要意义。  相似文献   

Decision making in sport: the effect of stimulus-response probability on the performance of a coincidence-anticipation task     

L Proteau  L Lévesque  L Laurencelle  Y Girouard 《Research quarterly for exercise and sport》1989,60(1):66-76

The purpose of the present study was to evaluate the quality of a motor response for different levels of expectancy and time constraint, in a two-choice coincidence-anticipation task. The probability of each of the two events likely to be presented were varied across different levels as well as the speed of the stimulus to be intercepted. The results indicated that neither the choice reaction time (CRT) and movement time, nor the performance of coincidence-anticipation were affected by the probability of the stimulus for the low and moderate stimulus speeds. However, when the stimulus traveled at a high speed a trade-off took place. The CRT decreased as the probability of the event increased, whilst the proportion of response initiation errors increased for the low probability events. This trade-off resulted in a better coincidence-anticipation as the probability of the event increased. The results obtained in the present experiment are clearly different from those obtained in a classic CRT-deadline paradigm, in that the trade-off observed between CRT and response initiation errors was far less pronounced in the coincidence-anticipation task. This difference was attributed to the higher negative consequences associated with a response initiation error in a coincidence-anticipation task. It is thus concluded that the tasks used to study the nature of the decision processes taking place in sports and sports-like situations must have some ecological validity to be of some help for the practitioner.  相似文献   

“There's a Great Big Beautiful Tomorrow': Historic Memory and Gender in Walt Disney's “Carousel of Progress”     

Lynn Y. Weiner 《Journal of American culture (Malden, Mass. : 2003)》1997,20(1):111-116

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E-journals from China: Technical and Collection Issues     

Yurong Y. Atwill   《The Journal of Academic Librarianship》2005,31(6):598-604

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Choice of Academic Major at a Public Research University: The Role of Gender and Self-Efficacy     

Iryna Y. Johnson  William B. Muse 《Research in higher education》2017,58(4):365-394

Females are underrepresented in certain disciplines, which translates into their having less promising career outlooks and lower earnings. This study examines the effects of socio-economic status, academic performance, high school curriculum and involvement in extra-curricular activities, as well as self-efficacy for academic achievement on choices of academic disciplines by males and females. Disciplines are classified based on Holland’s theory of personality-based career development. Different models for categorical outcome variables are compared including: multinomial logit, nested logit, and mixed logit. Based on the findings presented here, first generation status leads to a greater likelihood of choosing engineering careers for males but not for females. Financial difficulties have a greater effect on selecting scientific fields than engineering fields by females. The opposite is true for males. Passing grades in calculus, quantitative test scores, and years of mathematics in high school as well as self-ratings of abilities to analyze quantitative problems and to use computing are positively associated with choice of engineering fields.  相似文献   

Making Space for Place: Mapping Tools and Practices to Teach for Spatial Justice     

Laurie H. Rubel  Maren Hall-Wieckert  Vivian Y. Lim 《学习科学杂志》2017,26(4):643-687

This article presents a set of spatial tools for classroom learning about spatial justice. As part of a larger team, we designed a curriculum that engaged 10 learners with 3 spatial tools: (a) an oversized floor map, (b) interactive geographic information systems (GIS) maps, and (c) participatory mapping. We analyze how these tools supported learning using notions of politicization. The floor map fed conceptual understandings of the map as a representational text and served as the terrain for an embodied activity to support proportional reasoning about inequitable distributions of resources. The data-rich GIS maps and their zoomability allowed for coordinating across multiple variables to connect patterns in inequities to other social processes. The participatory mapping enabled learners to make discoveries about, connect, and share beyond the individual classroom counterstories from people in the lived streets of their neighborhood. In aggregate, this set of spatial tools produced a complex, hybrid view of the city’s space, which contributed to learners’ political formation.  相似文献   

Leveraging critical literacies for social change: questioning the culture of compliance at an ‘F’ school     

Katherine Crawford-Garrett  Michelle Perez  Amanda Y. Short 《Teaching Education》2017,28(3):227-243

This article traces the experiences of two veteran elementary school teachers in the urban Southwest, who are positioned by district and state policy ‘texts’ as insubordinate and failing, and who employ critical literacy practices to reconstruct and redesign these texts as they seek to create more equitable and humane conditions in schools. Stemming from a larger phenomenological study, this article explores how teachers in a ‘failing’ elementary school in the Southwestern US understand and negotiate district, state, and federal policies and examines how these policies shape and inform their identities as professionals. This research has important implications concerning the potential of critical literacy as a mode of resistance, the promise inherent in school/university partnerships for promoting change, and the ways in which the practice of deconstructing/reconstructing dehumanizing texts can foster a re-professionalization of teaching.  相似文献   

Patterns of participation in year 9 academic testing and factors predicting absence on the day of test     

Janice W. Y. Wong  Melissa O’Donnell  Donna Bayliss  Janet Fletcher  Rebecca Glauert 《Educational Research for Policy and Practice》2017,16(2):109-127

Policies aiming to improve educational outcomes are typically based on academic testing data. However, such data only reflect the performance of students who completed the tests. It is possible that students who were absent have shared characteristics. The proportion of students absent out of all eligible school students and whether they have shared characteristics has not been investigated, as this is only possible through the use of linked administrative data. Participants were born in Western Australia in 1994 and 1995, and their birth records were linked to participation status in the Year 9 academic tests to determine the proportion of students who were absent. Logistic regression was conducted to investigate characteristics which predicted absence on test day. A proportion of non-Aboriginal (3.2 %) and Aboriginal students (21.9 %) were absent on test day. Risk factors which predicted the absence included contact with Child Protection and Family Services, history of maternal mental health problems, and fathers aged below 20 years at the time of their child’s birth. A significant proportion of students was absent and therefore not represented in academic achievement information. These students were more likely to have experienced adverse events and therefore are not randomly absent. As these data are typically used to inform policies which aim to improve educational outcomes, they may lack the necessary information to adequately address the complex needs of students who are absent on test day. However, findings suggest that service providers, as well as schools may play an important role in encouraging participation in school.  相似文献   

中国委陵菜属植物研究   总被引：2，自引：0，他引：2  

俞德浚  李朝銮 《中国科学院研究生院学报》1980,18(1):1-14

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