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51.
S Grant T Hasler C Davies T C Aitchison J Wilson A Whittaker 《Journal of sports sciences》2001,19(7):499-505
There is limited information on the anthropometry, strength, endurance and flexibility of female rock climbers. The aim of this study was to compare these characteristics in three groups of females: Group 1 comprised 10 elite climbers aged 31.3 +/- 5.0 years (mean +/- s) who had led to a standard of 'hard very severe'; Group 2 consisted of 10 recreational climbers aged 24.1 +/- 4.0 years who had led to a standard of 'severe'; and Group 3 comprised 10 physically active individuals aged 28.5 +/- 5.0 years who had not previously rock-climbed. The tests included finger strength (grip strength, finger strength measured on climbing-specific apparatus), flexibility, bent arm hang and pull-ups. Regression procedures (analysis of covariance) were used to examine the influence of body mass, leg length, height and age. For finger strength, the elite climbers recorded significantly higher values (P < 0.05) than the recreational climbers and non-climbers (four fingers, right hand: elite 321 +/- 18 N, recreational 251 +/- 14 N, non-climbers 256 +/- 15 N; four fingers, left hand: elite 307 +/- 14 N, recreational 248 +/- 12 N, non-climbers 243 +/- 11 N). For grip strength of the right hand, the elite climbers recorded significantly higher values than the recreational climbers only (elite 338 +/- 12 N, recreational 289 +/- 10 N, non-climbers 307 +/- 11 N). The results suggest that elite climbers have greater finger strength than recreational climbers and non-climbers. 相似文献
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Martin R?tteler 《Informatik - Forschung und Entwicklung》2006,55(3):3-20
Quantum algorithms are a field of growing interest within the theoretical computer science as
well as the physics community. Surprisingly, although the number of researchers working on the subject
is ever-increasing, the number of quantum algorithms found so far is quite small. In fact, the task of
designing new quantum algorithms has been proven to be extremely difficult. In this paper we give an overview
of the known quantum algorithms and briefly describe the underlying ideas. Roughly, the algorithms presented
are divided into hidden subgroup type algorithms and in amplitude amplification type algorithms. While
the former deal with problems of group-theoretical nature and have the promise to yield strong separations
of classical and quantum algorithms, the latter have been proved to be a prolific source of algorithms
in which a polynomial speed-up as compared to classical algorithms can be achieved. We also discuss
quantum algorithms which do not fall under these two categories and give a survey of techniques of
general interest in quantum computing such as adiabatic computing, lower bounds for quantum algorithms,
and quantum interactive proofs. 相似文献
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This article discusses the changing relationships of authors and publishers, the current trends and challenges they face, and the direction of these relationships in the future. As the STM publishing industry finds itself in the midst of significant technological and economic changes, this article provides background to these changes and looks at the key elements, including open access business development, institutional repository trends, and emerging public financing policies in the future. 相似文献
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PETER J. ARNOLD 《Journal of Philosophy of Education》1992,26(2):237-255
ABSTRACT It is argued that sport, like science or medicine, is a valued human practice and is characterised as much by the moral manner in which its participants conduct themselves as by the pursuit of its own skills, standards and excellences. Virtues, such as justice, honesty and courage, are not only necessary to pursue its goals but to protect it from being corrupted by external interests. After explicating the practice view of sport in contrast to the sociological view, the nature of competition in sport is discussed before examining two related issues: winning at all costs and the taking of performance-enhancing drugs. The importance of practices to education and the good life is also outlined. 相似文献