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51.
Hillman CH Belopolsky AV Snook EM Kramer AF McAuley E 《Research quarterly for exercise and sport》2004,75(2):176-185
Electrocortical and behavioral responses of low, moderate, and high physically active older adults were compared with a younger control group on neutral and incompatible conditions of a flankers task. Compared to younger adults, high and moderate active older adults exhibited increased event-related potentials component P3 amplitude for the incompatible condition at the frontal electrode site. For the neutral condition, only low active older adults exhibited decreased amplitude at the central-parietal site, compared to younger adults. P3 latency revealed the longest latencies for low active older adults, followed by moderate active, high active, and younger adults, respectively. Reaction time (RT) data revealed that younger adults exhibited faster RT compared to all three older groups. Results suggest that physical activity may improve executive control function in older adults by affecting the distribution of P3 amplitude, which has been related to memory and attentional processes, and by decreasing P3 latency, which relates to the speed of cognitive processing. 相似文献
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Edward Barrow 《Learned Publishing》1998,11(4):259-263
Rightsholders' groups have given CLA approval to develop sector-by-sector licences for the digitisation of existing print material. The first two licences, for pharmaceutical regulatory submissions and for higher education, are approaching completion. Rightsholders will be asked to opt-in to each of them and to determine applicable fees for each of their publications. 相似文献
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The “Advances in Library Data and Access” column examines technological advances internal and external to libraries. The focus is on how library data is created and used. The strength of the column is its broad, international focus and contributors are encouraged to explore issues and recent advances in information technology relevant to their geographical region, as well as the larger, global audience. Interested authors are invited to submit proposals and articles to the column editor at moulaisonhe@missouri.edu. Please include “IILR Submission” in the subject line of the e-mail. 相似文献
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Laursen PB Knez WL Shing CM Langill RH Rhodes EC Jenkins DG 《Journal of sports sciences》2005,23(10):1111-1120
The aim of the present study was to examine the relationship between the performance heart rate during an ultra-endurance triathlon and the heart rate corresponding to several demarcation points measured during laboratory-based progressive cycle ergometry and treadmill running. Less than one month before an ultra-endurance triathlon, 21 well-trained ultra-endurance triathletes (mean +/- s: age 35 +/- 6 years, height 1.77 +/- 0.05 m, mass 74.0 +/- 6.9 kg, = 4.75 +/- 0.42 l x min(-1)) performed progressive exercise tests of cycle ergometry and treadmill running for the determination of peak oxygen uptake (VO2peak), heart rate corresponding to the first and second ventilatory thresholds, as well as the heart rate deflection point. Portable telemetry units recorded heart rate at 60 s increments throughout the ultra-endurance triathlon. Heart rate during the cycle and run phases of the ultra-endurance triathlon (148 +/- 9 and 143 +/- 13 beats x min(-1) respectively) were significantly (P < 0.05) less than the second ventilatory thresholds (160 +/- 13 and 165 +/- 14 beats x min(-1) respectively) and heart rate deflection points (170 +/- 13 and 179 +/- 9 beats x min(-1) respectively). However, mean heart rate during the cycle and run phases of the ultra-endurance triathlon were significantly related to (r = 0.76 and 0.66; P < 0.01), and not significantly different from, the first ventilatory thresholds (146 +/- 12 and 148 +/- 15 beats x min(-1) respectively). Furthermore, the difference between heart rate during the cycle phase of the ultra-endurance triathlon and heart rate at the first ventilatory threshold was related to marathon run time (r = 0.61; P < 0.01) and overall ultra-endurance triathlon time (r = 0.45; P < 0.05). The results suggest that triathletes perform the cycle and run phases of the ultra-endurance triathlon at an exercise intensity near their first ventilatory threshold. 相似文献
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Edward P. Hyde P.W. Cobb H.M. Johnson W. Weniger 《Journal of The Franklin Institute》1920,189(3):331-369
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Royalties, evolving patent rights, and the value of innovation 总被引:1,自引:0,他引:1
Edward F. Sherry 《Research Policy》2004,33(2):179-191
The value of an innovation to the innovator can change over time, especially in response to changes in the legal protection (such as patent rights) afforded the innovator. A proven-valid-and-infringed patent is a more valuable economic commodity than is an untested patent. The increase in value can be estimated using the success rate of patent lawsuits. Using a database of the outcomes of U.S. patent litigation, we find that plaintiffs win patent litigation some 45% of the time at the trial court level. This has implications both for patent damages awards and for the incentives to innovate. 相似文献
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