Biomechanical analysis of different starting strategies utilized during cross-country skiing starts

The present study was designed to analyse and compare the kinetics and kinematics associated with three different starting strategies during classic cross-country ski racing. Inside a ski tunnel, 12 elite male skiers performed three sets of three 38?m starts. Each set included one start using: double poling only (DP), diagonal stride only (DIA) and freely chosen (FREE) (i.e. where subjects used the strategy or combination of strategies they felt was fastest) in random order. The first 18?m was performed on a series of force plates that measured horizontal and vertical forces followed by 20?m of a standard snow track. Additionally, cycle characteristics and joint angles were measured. DIA and FREE were faster over 38?m than DP (P?.01). Net horizontal impulse (taking into account both positive and negative impulses) 5–10?m after the start was lower during DP than during DIA and FREE (both P?<?.05). All subjects skied faster when using only DIA for the entire 38?m. Furthermore, the sum duration and frequency of propulsive contacts over the first 18?m was less in DP than DIA and FREE (P?相似文献   

Stages in the History of Algebra with Implications for Teaching

In this article, we take a rapid journey through the history of algebra, noting the important developments and reflecting on the importance of this history in the teaching of algebra in secondary school or university. Frequently, algebra is considered to have three stages in its historical development: the rhetorical stage, the syncopated stage, and the symbolic stage. But besides these three stages of expressing algebraic ideas, there are four more conceptual stages which have happened along side of these changes in expressions. These stages are the geometric stage, where most of the concepts of algebra are geometric ones; the static equation-solving stage, where the goal is to find numbers satisfying certain relationships; the dynamic function stage, where motion seems to be an underlying idea, and finally, the abstract stage, where mathematical structure plays the central role. The stages of algebra are, of course not entirely disjoint from one another; there is always some overlap. We discuss here high points of the development of these stages and reflect on the use of these historical stages in the teaching of algebra. Commentary from a Mathematics Educator Bill Barton. See also the last page. Commentary from a Mathematics Educator     

Creativity in the Hong Kong classroom: What is the contextual practice?

A review is offered of Hong Kong's current education reform that sites a key role for creativity. This key role leads us to ask “Creativity in the Hong Kong Classroom: what is the contextual practice?” To address this question 27 Primary classroom teachers across three subject areas were observed and rated using the Classroom Observation Form [Furman, A. (1998). Teacher and pupil characteristics in the perception of the creativity of classroom climate. Journal of Creative Behavior, 32(4), 258–277]. The creativity potential of these teachers was then measured against the Creativity Fostering Teacher Index [Soh, K. C. (2000). Indexing creativity fostering teacher behavior: A preliminary validation study. Journal of Creative Behavior, 34(2), 118–134] and the Creative Personality Scale [Gough, H. G. (1978). A creative personality scale for the adjective check list. Journal of Personality and Social Psychology, 37(8), 1398–1405]. Their class students then completed the Chinese Creativity Tests [Wu, J. J., & Chen, F. X. (1998). A study on the new creativity test. Taiwan: Education Bureau and Foundation for Scholarly Exchange]. Findings support and extend current understandings of both system and componential theory [Csikzentmihalyi, M. (1996). Creativity: flow and the psychology of discovery and invention. New York: Harper Collins; Amabile, T. M. (1996). The social psychology of creativity. New York: Springer–Verlag; Amabile, T. M. (1996). Creativity in context. Boulder: Westview Press]. Instrument limitations and a need for interpretative cautions are discussed and their significance for further research indicated.     

The effect of frequency of testing upon the measurement of achievement in an intensive time-series design

Progress in the development of an intensive time-series design for use in classroom situations has raised several questions regarding the validity of the data obtained. One such question is related to the effect of frequency of testing upon the data. This study was designed to determine the presence of such an effect. Use of the design with eighth grade students studying a unit on crustal evolution indicated that the frequency of data collection did not adversely affect student attitudes toward the science class nor did it have any measurable effect upon class achievement data. The results of a previous study were also replicated, giving increased confidence in the validity of the data yielded by the intensive time-series design as used in these studies.     

Faculty Service Loads and Gender: Are Women Taking Care of the Academic Family?

This paper investigates the amount of academic service performed by female versus male faculty. We use 2014 data from a large national survey of faculty at more than 140 institutions as well as 2012 data from an online annual performance reporting system for tenured and tenure–track faculty at two campuses of a large public, Midwestern University. We find evidence in both data sources that, on average, women faculty perform significantly more service than men, controlling for rank, race/ethnicity, and field or department. Our analyses suggest that the male–female differential is driven more by internal service—i.e., service to the university, campus, or department—than external service—i.e., service to the local, national, and international communities—although significant heterogeneity exists across field and discipline in the way gender differentials play out.     

What if we could Imagine an Ideal University? Narratives by Students with Disabilities

This article presents the results of a project entitled, ‘Analysis of University Barriers and Aids Identified by Students with Disabilities’, carried out in a Spanish University. The study used the biographical–narrative methodology, which emphasises the importance of people talking about themselves without silencing their subjectivity. Different types of data collection instruments, such as biographic interview, timelines and photography, were employed to acquire this information. The Results section presents proposals made by students with disabilities which could contribute to developing a more inclusive university. Some of their suggestions were that students with disabilities should be better informed and oriented, academic staff should be better trained to favour their educational inclusion, the settings and infrastructures should be accessible, and universities should be prepared to deal with people with disabilities. The conclusions discuss the main findings of the analysis, comparing them with other previous studies, and making some proposals that help universities progress towards inclusive education.     

Assessing multicultural competence (knowledge and awareness) in study abroad experiences

This study was designed to evaluate the effectiveness of the study abroad experience on student multicultural competence (i.e. knowledge and awareness) using the Multicultural Counselling Knowledge and Awareness Scale in two study abroad programmes during four separate yearly excursions. The first study abroad programme incorporated cultural immersion and two courses taught over five weeks in Germany. The second five-week study abroad programme focused on exploring non-governmental organisations and development as well as multicultural competence in India. Effect size results indicate that both direct and indirect approaches to increasing multicultural competence can be effective in exposing students to diverse immersive multicultural perspectives, norms, rituals, and practices.