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101.
The aim of this study was to establish whether asymmetry of the strength of the leg and trunk musculature is more prominent in rowers than in controls. Nineteen oarsmen and 20 male controls matched for age, height and body mass performed a series of isokinetic and isometric strength tests on an isokinetic dynamometer. These strength tests focused on the trunk and leg muscles. Comparisons of strength were made between and within groups for right and left symmetry patterns, hamstring: quadriceps ratios, and trunk flexor and extensor ratios. The results revealed no left and right asymmetries in either the knee extensor or flexor strength parameters (including both isometric and isokinetic measures). Knee extensor strength was significantly greater in the rowing population, but knee flexor strength was similar between the two groups. No difference was seen between the groups for the hamstring: quadriceps strength ratio. In the rowing population, stroke side had no influence on leg strength. No differences were observed in the isometric strength of the trunk flexors and extensors between groups, although EMG activity was significantly higher in the rowing population. Patterns of asymmetry of muscle activity were observed between the left and right erector spinae muscles during extension, which was significantly related to rowing side (P < 0.01). These observations could be related to the high incidence of low back pain in oarsmen. 相似文献
102.
A. D. C. Peterson Brian Holmes G. De Landsheere Helena W. F. Stellwag Oskar Anweiler J. O. J. Vanden Bossche Abraham Robinson F. I. Calvert H. H. Stern J. F. Willatt Sydney Taylor M. J. Langeveld M. A. Brimer T. N. Postlethwaite Alexandre Vexliard 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1964,10(1):106-126
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M.O. Ahmad C.H. Reddy V. Ramachandran M.N.S. Swamy 《Journal of The Franklin Institute》1979,307(2):71-81
Necessary and sufficient conditions are obtained for the realization of an m-variable positive real function (PRF) as the impedence function of a resistively-terminated ladder network of m lossless two-ports connected in cascade. Each two-port is a single-variable lossless ladder with all of its transmission zeros either at the origin or at finity. Conditions are also obtained when each of the two-ports is a Fujisawa-type lowpass ladder. 相似文献
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The graph theoretic aspects of controllability and observability are examined and related to the tensorial formulation of Part I of the paper. Particular emphasis is given to the significance of the system digraph decomposition and the relevance of this to certain system algebraic properties of interest in control theory. 相似文献
109.
Recently, March, Hooper, and Baum (1977) described a sample of 99 nonstudent elders in terms of their demographic characteristics and their attitudes toward lifelong learning. The sample was found to be well‐educated (mean years of education = 13.61, SD = 9.43), active in the community, well‐read, and fairly affluent. The majority demonstrated a quite open attitude toward the appropriateness of formal education in old age, but also felt that learning can be acquired outside the classroom: “living is learning.” The present study was undertaken to similarly describe a sample of elderly people enrolled in the University of Wisconsin guest student program, and to contrast these respondents with those in the earlier study. The student group was found to be significantly younger than the nonstudent group (mean = 70.78, SD = 7.21 vs. mean = 74.69, SD = 8.45; t = 2.87, p < .001). Although there is no difference in the mean years of education of the two groups, there is significantly greater variability in years of education in the student group (F = 10.98, p < .001), with 50.4% of the nonstudent group versus 21.6% of the student group having 12 years of education or less. Additionally, it was found that only 10 of the 139 student respondents did not have either personal or vicarious personal (through familial significant others) experience with higher education in youth. The respondents’ stated preference for class format and student group age is also summarized, and some implications for educational gerontology are discussed. 相似文献
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Zi Yue’er 《中外文化交流(英文版)》2012,(1):8-11
From October 22 to 30, 2011, the 13th China Wuqiao Acrobatic Festival was held in Shijiazhuang, north China’s Hebei province.Co-organized by the Ministry of Culture of China and Hebei People’s Provincial Government, this biennial event featured the theme of "developing acrobatic art, facilitating international exchanges,promoting economic and social development,and enriching people’s cultural life". This year,the festival attracted more than 200 acrobats from 27 circus companies from 17 countries and regions around the world, including Russia,Canada, USA, DPRK, Australia and France, who 相似文献