Modeling of chemotactic steering of bacteria-based microrobot using a population-scale approach     

Sunghoon Cho  Young Jin Choi  Shaohui Zheng  Jiwon Han  Seong Young Ko  Jong-Oh Park  Sukho Park 《Biomicrofluidics》2015,9(5)

The bacteria-based microrobot (Bacteriobot) is one of the most effective vehicles for drug delivery systems. The bacteriobot consists of a microbead containing therapeutic drugs and bacteria as a sensor and an actuator that can target and guide the bacteriobot to its destination. Many researchers are developing bacteria-based microrobots and establishing the model. In spite of these efforts, a motility model for bacteriobots steered by chemotaxis remains elusive. Because bacterial movement is random and should be described using a stochastic model, bacterial response to the chemo-attractant is difficult to anticipate. In this research, we used a population-scale approach to overcome the main obstacle to the stochastic motion of single bacterium. Also known as Keller-Segel''s equation in chemotaxis research, the population-scale approach is not new. It is a well-designed model derived from transport theory and adaptable to any chemotaxis experiment. In addition, we have considered the self-propelled Brownian motion of the bacteriobot in order to represent its stochastic properties. From this perspective, we have proposed a new numerical modelling method combining chemotaxis and Brownian motion to create a bacteriobot model steered by chemotaxis. To obtain modeling parameters, we executed motility analyses of microbeads and bacteriobots without chemotactic steering as well as chemotactic steering analysis of the bacteriobots. The resulting proposed model shows sound agreement with experimental data with a confidence level <0.01.  相似文献   

Teachers' Perceptions of Teaching Environmental Issues Within the Science Curriculum: A Hong Kong Perspective     

Andre Chi-chung Ko  John Chi-kin Lee 《Journal of Science Education and Technology》2003,12(3):187-204

The present study was an exploratory study of Hong Kong secondary school Integrated Science teachers' perceptions of environmental education. Both questionnaire survey and interviews were used. Teachers were classified according to their scores of attitudes, perceived barriers, and current emphasis on teaching environmental education. This study found that Integrated Science teachers' attitudes toward environmental education, skills of teaching environmental education, beliefs in the relevance of Integrated Science to environmental education, and intentions of teaching environmental education in Integrated Science classes were associated with their actual ways of teaching of environmental education. Teachers tended to teach more environmental education if they held more favorable attitudes toward environmental education, had more skills of teaching environmental education, believed more in the relevance of Integrated Science to environmental education, and would actually want to teach more environmental education in Integrated Science classes if there were fewer constraints. Moreover, variations in the teaching of environmental education were reflected by teachers' emphasis on teaching environmental education, and their use of a variety of teaching methods and their regular practices of extracurricular activities on environmental education.  相似文献   

An evaluation of accessibility to preschool education institutions using geographic information systems     

Köse  Mustafa  Koçyiğit  Mehmet  Erdem  Cahit  Jega  Idris Mohammed 《Education and Information Technologies》2021,26(4):4307-4328

Education and Information Technologies - This study aims to evaluate current locations of preschool education institutions and suggest alternative spatial arrangements in the Afyonkarahisar...  相似文献   

Physical activities during pregnancy and type of delivery in nulliparae     

Yi-Li Ko  Chie-Pein Chen 《European Journal of Sport Science》2016,16(3):374-380

The aim of this study was to investigate changes in physical activity across pregnancy and the relationship between trimester-specific physical activity and unplanned caesarean sections (CSs). A cohort study design was carried out. A cohort of 150 pregnant women was established when they received prenatal care at 29–40 weeks of gestation at a medical centre in northern Taiwan. Participants were asked to recall the amounts of physical activity in which they had engaged in the three trimesters as assessed by the Pregnancy Physical Activity Questionnaire (PPAQ). Overall self-reported physical activity for the cohort decreased by 31% in the first trimester compared to the pre-gravid period, then increased in the second trimester and remained stable until delivery. A repeated measures analysis of variance was used to evaluate the data and revealed significantly more physical activity during the second trimester than in the first and third trimesters (F = 36.471, P = 0.000). In addition, there was a significant difference between normal spontaneous delivery and unplanned CS groups (F = 4.770, P = 0.031). Logistic regression determined that the odds ratio of undergoing a CS increased by 0.644 (95% confidence interval: 0.429–0.968) for women in the third trimester who performed low levels of physical activity. Results support the benefits of physical activity, and professionals are encouraged to provide pregnant women with information on recommendations for physical activity, particularly in terms of reducing unplanned CSs.  相似文献   

More student trust,more self-regulation strategy? Exploring the effects of self-regulatory climate on self-regulated learning     

John Chi Kin Lee  Sammy King Fai Hui  Po Yuk Ko 《The Journal of educational research》2019,112(4):463-472

Self-regulated learning has been one of the important areas in educational research. The authors adopted structural equation modeling to explore and compare the impacts of three aspects of self-regulatory climate (i.e., academic emphasis, teacher trust, and student trust) on three features of self-regulated learning (i.e., self-efficacy, intrinsic motive, and self-regulation strategy). The results revealed both direct effects of academic emphasis on students’ use of self-regulation strategy, and indirect effects mediated by self-efficacy and intrinsic motive. Teacher trust has a positive impact on self-efficacy. While student trust has a positive impact on intrinsic motive, its relationship with self-regulation strategy is negative. Significant differences in school levels and gender were identified. The findings indicate that students in different cultures may have different expectations for teachers’ support in learning, which in turn influence the relationship between student trust in teachers and the use of self-regulation strategy. Implications for cultivating self-regulated learners are discussed in the article.  相似文献   

FORMATION OF OTS SELF-ASSEMBLED MONOLAYER ON GLASS SURFACE INVESTIGATED BY AFM   总被引：2，自引：0，他引：2  

徐国华 《Journal of Zhejiang University. Science. B》2000,(2)

ＩＮＴＲＯＤＵＣＴＩＯＮＳｉｎｃｅＳａｇｉｖ(1980)ｉｎｖｅｓｔｉｇａｔｅｄｔｈｅｒｅａｃｔｉｏｎｏｆｏｃｔａｄｅｃｙｌｔｒｉｃｈｌｏｒｏｓｉｌａｎｅ(ＯＴＳ)ｍｏｌｅｃｕｌｅｓｗｉｔｈｓｌｉｄｅｇｌａｓｓｐｌａｔｅｓｔｏｆｏｒｍｓｅｌｆａｓｓｅｍｂｌｅｄｍｏｎｏｌａｙｅｒｓｉｎ1980ｆｏｒｔｈｅｆｉｒｓｔｔｉｍｅ,ｍａｎｙｒｅｓｅａｒｃｈｅｓｈａｖｅｂｅｅｎｃｏｎｄｕｃｔｅｄｔｏｓｔｕｄｙｔｈｅｆｏｒｍａｔｉｏｎｏｆＯＴＳｍｏｎｏｌａｙｅｒｓｏｎｍｉｃａ,ｓｉｌｉｃｏｎ,ｓｉｌｉｃａａｎｄｇｌａｓｓｓ…  相似文献   

A flexible approach to reassembling thin artifacts of unknown geometry     

Geoffrey Oxholm  Ko Nishino 《Journal of Cultural Heritage》2013,14(1):51-61

We present a novel 3D reassembly method for fragmented, thin objects with unknown geometry. Unlike past methods, we do not make any restrictive assumptions about the overall shape of the object, or its painted texture. Our key observation is that regardless of the object's shape, matching fragments will have similar geometry and photometry along and across their adjoining regions. We begin by encoding the scale variability of each fragment's boundary contour in a multichannel, 2D image representation. Using this multichannel boundary contour representation, we identify matching sub-contours via 2D partial image registration. We then align the fragments by minimizing the distance between their adjoining regions while simultaneously ensuring geometric continuity across them. The configuration of the fragments as they are incrementally matched and aligned form a graph structure that we use to improve subsequent matches. By detecting cycles in this graph, we identify subsets of fragments with interdependent alignments. We then minimize the error within the subsets to achieve a globally optimal alignment. We leverage user feedback to cull the otherwise exponential search space; after each new match is found and aligned, it is presented to a user for confirmation or rejection. Using ceramic pottery as the driving example, we demonstrate the accuracy and efficiency of our method on six real-world datasets.  相似文献   

The Development of Chinese Martial Arts in Taiwan since 1949     

Ling-Mei Ko  Meng-Chi Ting 《国际体育史杂志》2013,30(15):1603-1616

Abstract

In Taiwan, the historical development of traditional Chinese martial arts, or kuoshu and wushu as they are called today, has been quite diverse. This paper examines the development of Chinese martial arts from 1949 to 2017 in the context of Taiwan based on available historical evidence and in-depth interviews. The results show that there were three major historical periods in the development of Chinese martial arts. The foundation period was inaugurated when Chinese martial artists fled to Taiwan with the Nationalists. During this period, martial arts studios spread throughout the country and people began learning the traditional Chinese martial arts skills together with the national physical education curriculum incorporated martial arts in schools. Chinese martial arts in Taiwan then entered the competitive sports period when the Chinese government to promote competitive martial arts internationally and to standardize the practice and grading system required for competitions. During this period, standardized rules for nationwide competition were established, and sports instructors and athletes were trained to participate in international wushu competitions. Currently, the Chinese martial arts have been modernized and being practised to build confidence, mental discipline, and physical strength as well as for self-defence, recreational pursuits, and competition.  相似文献   

Teaching mathematically talented students: a cross-cultural study about their teachers’ views     

Bruria Shayshon  Hagar Gal  Bertha Tesler  Eun-Sung Ko 《Educational Studies in Mathematics》2014,87(3):409-438

The instruction of mathematically talented students (MTS) in heterogeneous classes is an issue of debate. Questions of equity, differential instruction, teacher awareness of their talented students’ needs, and their willingness and competence to face the challenges of nurturing these students are all raised within this context. Our international study compared South Korean, American, and Israeli teachers of mathematics perspectives concerning their (a) perceived competence to teach MTS (b) perceived competence in addressing MTS’ needs through differential instruction, (c) support for separation of MTS into special math classes, and (d) equity views concerning MTS’ needs. Data was collected by means of a questionnaire presented to 80 South Korean, 145 Israeli, and 58 American teachers of mathematics. Findings suggested that most teachers in these countries perceived themselves as competent to teach MTS, while very few of the participants supported the separation of MTS into special classes. South Korean teachers perceived themselves to be less competent in teaching MTS as well as in applying differential instruction and agreed more than their foreign counterparts that the fostering of mathematically weak students is more important than the fostering of MTS. Teachers who had some mathematical background appeared to perceive themselves as more competent to teach MTS than teachers who had no mathematical background. Teachers who predominantly taught large classes felt less competent to teach MTS than teachers who predominantly taught medium-sized classes. Findings were partially interpreted within the perspective of cultural differences. Recommendations for teachers’ professional development are drawn.  相似文献   

Editorial     

Matsuura  Koïchiro 《Prospects》2004,34(2):137-140

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