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In three experiments, rats received pairings of flavor conditioned stimuli with polycose unconditioned stimuli, in either
a simultaneous or a sequential relation. Both temporal relations produced excellent conditioned increases in consumption of
the flavors. Separate presentation of the flavors resulted in extinction in both cases. However, restoring the pairing of
the flavor with polycose resulted in reconditioning only with the sequential, not with the simultaneous, relation. 相似文献
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关于广东省普通高校体育专业招生考试足球项目考试内容、方法及评分标准的研究 总被引:1,自引:0,他引:1
采用调查访问、实验法对广东省普通高校体育专业招生考试足球项目考试内容、方法及评分标准进行研究,通过研究.足球非专项考试难度偏低的问题、足球专项考试方法中颠球、绕杆射门项目考试难度偏低以及踢准项目偏难等问题得到解决,从而确立了广东省新的足球专项、非专项考试的各项内容、方法及评分标准,为广东省考试中心组织实施2005年广东省普通高校体育专业招生考试提供了具有实效性和科学性的保证。 相似文献
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Brian S Alper Jason A Hand Susan G Elliott Scott Kinkade Michael J Hauan Daniel K Onion Bernard M Sklar 《Journal of the Medical Library Association》2004,92(4):429-437
OBJECTIVES: Medicine must keep current with the research literature, and keeping current requires continuously updating the clinical knowledge base (i.e., references that provide answers to clinical questions). The authors estimated the volume of medical literature potentially relevant to primary care published in a month and the time required for physicians trained in medical epidemiology to evaluate it for updating a clinical knowledge base. METHODS: We included journals listed in five primary care journal review services (ACP Journal Club, DynaMed, Evidence-Based Practice, Journal Watch, and QuickScan Reviews). Finding little overlap, we added the 2001 "Brandon/Hill Selected List of Print Books and Journals for the Small Medical Library." We counted articles (including letters, editorials, and other commentaries) published in March 2002, using bibliographic software where possible and hand counting when necessary. For journals not published in March 2002, we reviewed the nearest issue. Five primary care physicians independently evaluated fifty randomly selected articles and timed the process. RESULTS: The combined list contained 341 currently active journals with 8,265 articles. Adjusting for publication frequency, we estimate 7,287 articles are published monthly in this set of journals. Physicians trained in epidemiology would take an estimated 627.5 hours per month to evaluate these articles. CONCLUSIONS: To provide practicing clinicians with the best current evidence, more comprehensive and systematic literature surveillance efforts are needed. 相似文献
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Soper C Hume PA 《Sports biomechanics / International Society of Biomechanics in Sports》2004,3(2):237-248
Coaches, sport scientists and researchers assess rowing performance on-water and on a variety of ergometers. Ergometers are frequently used because of the easier assessment environment. However, there is limited information on the ability of rowers to reproduce mean power or time-trial time when using different rowing ergometers (Concept II and RowPerfect) or completing tests over different distances (500 m versus 2000 m races). To test the efficacy of an intervention on a rower's ability to produce power, or to monitor that ability, it is essential to determine a reliable rowing performance test. The per cent standard error of measurement in performance (assessed by mean power and time-trial time) of fifteen national standard rowers was determined for five repeated 500 m and two repeated 2000 m races on a Concept II and RowPerfect ergometer. The per cent standard error of measurement (% SEM) in mean power between 5x500m races, regardless of gender, was 2.8% (95% confidence limits (CL)=2.3 to 3.4%) for the Concept II ergometer and 3.3% (95% CL=2.5 to 3.9%) for the RowPerfect ergometer (n = 15). Over 2000 m the per cent standard error of measurement in mean power was 1.3% (95% CL 0.9 to 2.9%) for the Concept II ergometer and 3.3% (95% CL 2.2 to 7.0%) for the RowPerfect ergometer The results highlight an increase in per cent standard error of the mean during performance races of less than 2000m on the Concept II ergometer, and performance races on the RowPerfect ergometer compared with the Concept II ergometer over 500 m and 2000 m. The most appropriate protocol for testing the influence of an intervention on the ability of a rower to produce power would be 2000 m races on a Concept II ergometer. 相似文献
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Conclusions We are living a deep change in the information transfer process involving the different actors of the editorial scene (from
authors to editors, web-editors, e-publishers and readers), who occasionally play different roles at the same time (e.g.,
authors sometimes bypass the editor thus assuming direct responsibilities in the diffusion of documents in the Internet).
Furthermore, information producers, managers or seekers often show twofold personalities like Dr. Jekyll and Mr. Hyde. They
would like to find all documents free on the Internet and be able to read original, reliable, and high quality information,
but they are sometimes reluctant to spread their papers through online nonofficial channels as they care for the impact factor,
prestige, and career advancement.
It is a revolutionary period in which new and alternative forms of scholarly communication live together with more traditional
ones and the future is difficult to define. Recent initiatives of open access—such as Pubmed Central, Public Library of Science,
Budapest Open Access Initiative—are contributing to define new trends in the editorial market, challenging the traditional
distribution channels, mainly managed by commercial editors, and placing the authors’ role and publication copyrights under
severe discussion.
In this landscape, GL now has new dignity and becomes closer and closer to innovative scientific publications supported by
researchers in view of a generalised movement towards open access. The nuances of grey are becoming lighter and lighter. The
questions are many, the answers few, but, in any case, the ethical responsibility of producing and issuing quality documents
can never be disregarded. 相似文献