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41.
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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The purpose of this study was to describe the development of elementary students' skill in making predictions and of their understanding of what predicting means. The study involved observing and assessing the performance of 167 children on the Physical Manipulation Test (PMT), a test involving the manipulation of science materials and equipment. Children were interviewed about what they understand predicting to mean, how they use it at school and at home, and why they think it is important. For each of the seven topics tested, even the youngest children were able to offer predictions. Accuracy varied with the topic, increasing between Grades 1 and 4 and leveling off after that. The increase in skill involved children's growing ability to attend to patterns discerned through their own observations. Four levels in the development of predicting skill, as it relates to particular topics, are described. Children's understanding of predicting showed steady improvement through Grade 6. Children's awareness of their use of predicting at school and at home, and their ability to explain the importance of predicting, also increased through Grades 1 to 6, with a spurt at Grade 4. Children understood predicting to be an internal process in which one uses knowledge to anticipate a future event; they regarded predicting as an important way of being intellectually involved with the world.  相似文献   
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The project of studying children in order to understand them, which lies at the heart of contemporary thinking about children and their education, is misconceived. It rests, jrst of all, upon a false belief that we can only come to know something properly by deliberately and systematically pursuing knowledge of it. Secondly, it offers a paradigm of knowing children which justifies parents and teachers in not giving themselves to children. By re-interpreting the problems that adults experience with children as technical, as arising from lack of information about them, it ignores the personal and moral dimension of adults' relations with children and thus further alienates them from one another.  相似文献   
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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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Do students today know less than their parents or grandparents did as students? Are they being academically outclassed by students of other nations? Or have ideologically driven policy makers painted an unnecessarily negative picture of student achievement?  相似文献   
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