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71.
The cadence that maximises power output developed at the crank by an individual cyclist is conventionally determined using a laboratory test. The purpose of this study was two-fold: (i) to show that such a cadence, which we call the optimal cadence, can be determined using power output, heart-rate, and cadence measured in the field and (ii) to describe methodology to do so. For an individual cyclist's sessions, power output is related to cadence and the elicited heart-rate using a non-linear regression model. Optimal cadences are found for two riders (83 and 70 revolutions per minute, respectively); these cadences are similar to the riders’ preferred cadences (82–92?rpm and 65–75?rpm). Power output reduces by approximately 6% for cadences 20?rpm above or below optimum. Our methodology can be used by a rider to determine an optimal cadence without laboratory testing intervention: the rider will need to collect power output, heart-rate, and cadence measurements from training and racing sessions over an extended period (>6 months); ride at a range of cadences within those sessions; and calculate his/her optimal cadence using the methodology described or a software tool that implements it.  相似文献   
72.
The topic of childhood vaccinations has received much news media attention recently, prompting scholars to examine how the public has responded. In light of this news, and the deep divide that seems to exist between parents who support childhood vaccinations and those who do not, this study examines how and why individuals may involve themselves in communication about vaccinations, particularly on social media or in other online environments. Focusing on the concept of communicative action and drawing from spiral of silence and other research, a survey of mothers (= 455) found that those who do not support childhood vaccinations are more likely to engage in communication about the issue, including information seeking, attending, forefending, permitting, forwarding, and sharing. In addition, issue importance and affective and cognitive involvement help drive communicative action regarding childhood vaccinations, which could affect public opinion or public perceptions of the issue. Theoretical and practical implications are discussed.  相似文献   
73.
贾庆文 《海外英语》2006,(12):34-35
当我四岁时,我把父母的胡桃木梳妆台上咬上牙印。他们没有看到我做这件事,但一次被发现了,他们并没有责备我。相反,40年来母亲充满深情地将牙印上的灰尘擦去。当我长大后,我问她为什么她从不将梳妆台的表面整修一下,她说,“我只是不想这样做。”直到我自己有了孩子我才能够完全理解这种情感。回忆孩子小时候的事情是人生最开心的事情之一。我的长子阿利屋夏如今20岁了,在外面上大学,但他少年时代的生活印记在我们房子里外到处都是。当他长大以后,我完成了使他长到门框边框的职责。偶尔我让他在靠着门框站立,测量他的身高,然后让他蹲到我们当…  相似文献   
74.
The aim of this study was to determine whether, as a result of collaborative-online reading of a chapter from a book of an academic nature, the quality of the collaborative summary that the readers would write would be higher than that written by readers who would both read the same chapter and write a summary in a face-to-face setting. In this study we examined the difference between the summaries written by participants from two groups, each group was divided into subgroups of 3 participants who had read collaboratively a chapter of a book, and collaborated on writing a summary. The participants of the experimental group read the chapter as it appeared in a website for collaborative reading built especially for this study and the participants were asked to summarize the chapter on a shared online digital document. The participants of the control group were asked to read the chapter face-to-face and to collaboratively summarize it in hand writing. The quality of the summaries was evaluated with a tool developed by Rivard (2001). This tool was developed to measure the quality of the summaries. In our study the main and secondary ideas that were supposed to be included in the participants’ summaries were identified by three literature teachers using ten different criteria and the summaries were analyzed by two other judges based on these criteria. The findings indicated that there were significant differences in the majority of the writing indicators being measured with the tool. The findings indicated that collaborative-online reading and writing produce a summary of a higher quality than one read and hand written collaboratively face-to-face.  相似文献   
75.
76.
Despite a substantial body of research suggesting genetic influence on educationally relevant behavioural traits, it is not clear how the nature–nurture question is perceived by teachers. In order to answer this question, we surveyed 667 UK primary school teachers, and for comparison also surveyed 1,340 parents about their perceptions of genetic and environmental influence on personality, intelligence, behaviour problems, learning difficulties, and mental illness. For these five domains of behaviour, the percentages of teachers who reported that genetics were at least as important as environment were .87, .94, .43, .94, and .91, respectively. Results for parents were similar (.92, .93, .54, .86, and .89). We also found that 80% of teachers reported no coverage of genetics during teacher training.  相似文献   
77.
Five suburban community colleges in a metropolitan area collaborated on a survey to parents of high school graduates of the class of 2002 who attended the colleges in fall 2002. The study was undertaken to learn more about parents roles in their students selection of community colleges, to give insights and information about this important community college constituency, and to assist community colleges to shape more effective ways to foster positive and supportive opinions among parents of potential students. Parents want the community college to provide students with credits and grade point averages enabling transfer, overestimate their students academic skills as measured by course placement tests, engaged in a number of college-choice activities, and indicate that factors associated with lifestyle and money were major reasons for selecting the community college. Associations between parents social capital and perceptions of their students academic abilities were found for a number of dependent variables examined. The study also revealed important differences in how participating institutions record and calculate key measures such as credits earned and grade point averages.  相似文献   
78.
学习“三个代表”的重要思想 ,必须坚持理论联系实际的马克思主义学风。要深入把握“三个代表”重要思想的理论根据和实践根据 ,更要研究怎样切实有效地实践“三个代表”。  相似文献   
79.
80.
Robert W. Bell 《PRIMUS》2017,27(3):406-417
Abstract

Mentoring undergraduate students in research is both rewarding and challenging. In this paper we present how we established a summer Research Experience for Undergraduates (REU) program in the mathematical sciences at Michigan State University. A goal of our REU is to include students who are at an early stage of their study of mathematics. We share our experiences in recruiting students, designing research projects, and mentoring our participants. We discuss the challenges we faced and the solutions we found while working with a diverse group of undergraduate students from across the nation.  相似文献   
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