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961.
Six Danish male cross-country skiers were studied during the end-of-summer and winter seasons. Their maximal oxygen uptake was measured while running on a treadmill and using a ski ergometer incorporating the double-poling technique. Maximal oxygen uptake during treadmill running and double-poling was correlated with performance, expressed as a ranking score during 10 ski races. The tests were undertaken in September, December and April. Upper body maximal oxygen uptake increased 5.8% from September to December, decreasing to 2.3% above the September level in April. Upper body work output (2 min at maximal intensity) increased 11.8% from September to December (P less than 0.05). The relationship between upper body and leg maximal oxygen uptake--the upper body/leg ratio--was 89.4% in September. In four skiers, both treadmill and upper body tests were undertaken on each test occasion. The upper body/leg ratio changed from 87.7% in September to 95.7% in December. In April, the ratio was 91.0%. The maximal oxygen uptake measured using the ski ergometer during double-poling was significantly correlated with performance (P less than 0.05). It is concluded that the upper body ski ergometer can be used in the evaluation of elite cross-country skiers. 相似文献
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Leslie E. Simon 《Journal of The Franklin Institute》1944,237(5):359-370
It is shown that wrong inferences are drawn from samples because of failure to understand what constitutes a lot and because of failure to verify the existence of a lot in the practically useful sense. Time-tried methods of making valid inferences from samples without increased cost are pointed out. 相似文献
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In March 1985, the National Library of Medicine (NLM) began implementation of DOCLINE, its automated interlibrary loan request routing and referral system. By the end of fiscal year (FY) 1987, over 1,400 biomedical libraries in all seven regions of the Regional Medical Library network were using the system. This report summarizes the findings of an analysis of the interlibrary loan (ILL) requests received in FY 1987, comparing the results with a similar analysis done in FY 1984 to describe any changes in the requests or service which might be attributable to DOCLINE implementation. DOCLINE has had a substantial impact upon ILL loan service at NLM. An increase in the number of ILL requests (35% over FY 1984) can be attributed to the speed and ease with which requests may be routed to NLM through DOCLINE. Requests which cannot be filled by local or regional libraries are automatically routed by the system to NLM as the library of last resort. NLM's fill rate for serial requests has declined, however, from 78% filled in FY 1984 to 67% filled in FY 1987. Some of the decline results from the 11,000 requests that NLM did not fill because the borrowing libraries were not willing to pay the NLM charge for filling the loans. 相似文献
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