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  • Scientific publication has been a key part of the scientific method since the inception of Philosophical Transactions in 1665.
  • The scientific publications industry has grown exponentially along with science, incorporating technological innovations along the way, and adapting journal processes and practices to changing needs of science as it matured.
  • Of all the technological innovations over more than 300 years, the move to online journals may be the most significant, making open access to content practical for the first time.
  • The open‐access movement is disrupting the economics of journal publishing, which is hoped will make the industry more competitive: the ability of the publications industry to adapt to open access will be a measure of its resilience.
  • The demand for articles published in reputable journals continues to grow as readers trust the credibility of peer reviewed journal articles, and good authors value the prestige of publishing in the best journals.
  • It is difficult to predict what new functionalities may be included in articles of the future or what additional services publishers and editors will provide, but there is every reason to believe that scientific journal articles are here to stay.
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Arterial spin labelling (ASL) provides a potential method to non-invasively determine muscle blood flow and examine the impact of interventions such as supplementation and training. However, it's a method with intrinsically low signal, leading to limitations in accuracy and temporal resolution. To examine these limitations, the current study measured perfusion via ASL on three occasions in the rectus femoris of 10 healthy adults, during light and moderate exercise, over three different exercise durations. For data sampled over 9 min, light intensity exercise gave an average perfusion of 35.0 ± 5.1 ml/min.100g?1 with a coefficient of variation (COV) of 16% and single intraclass correlation coefficient (ICC) of 0.67. For the moderate bout, perfusion was 51.3 ± 5.6 ml/min.100g?1 (COV 10%, ICC 0.82). When the same data were analyzed over 5 min 24 s, perfusion was 37.8 ± 11.13 (COV 30%, ICC 0.13) during light and 49.5 ± 8.8 ml/min.100g?1 (COV 18%, ICC 0.52) during moderate exercise. When sampling was reduced to 1 min 48 s, perfusion was 41.2 ± 13.7 (COV 33%, ICC 0.26) during light and 49.5 ± 13.6 ml/min.100g?1 (COV 28%, ICC 0.04) during moderate exercise. For 9 min a significant perfusion difference was found between the exercise intensities; however, this was not the case for sampling over 5 min 24 s or 1 min 48 s. Such findings illustrate the potential of ASL to non-invasively monitor muscle perfusion under steady-state conditions, but highlight that extended exercise protocols are necessary in order to generate date of sufficient reliability to be able to discriminate intervention dependent perfusion differences.  相似文献   
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Meta-analysis is an analysis of analyses. It is a technique widely used by researchers and practitioners to aggregate and summarize statistically reported empirical educational research. In 10 years, meta-analysis appeared more than 600 times in research journals and dissertation abstracts. Although most meta-analyses were reported as significant, few of the findings determined how many unpublished “no-effect” studies, if sampled, would have invalidated significance. If significant meta-analysis results are over represented through selective sampling, hucksterism in the form of sampling bias exists. An explanation for using a follow-up test called the fail-safe N is provided with tables constructed to assist researchers and practitioners to estimate, without calculation, the relative stability of meta-analysis results. The implication is that failsafe N should routinely be used and reported in meta-analysis research.  相似文献   
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Light's Retention Scale totals, along with measures of reading achievement, mathematics achievement, and self-concept taken at the time first grade nonpromotion was being considered, were used to predict nine separate outcome measures of academic, emotional, and social status at the end of the repeated first grade. In none of the stepwise regressions did the Light total add to the prediction of outcome in the children repeating the first grade. This result, added to earlier studies, suggests that Light's Retention Scale is neither reliable nor valid as a psychometric device.  相似文献   
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