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991.
992.
Christopher J. McNamara Margaret Breuker Marie Helms Thomas D. Perry Ralph Mitchell 《Journal of Cultural Heritage》2004,5(4):361-364
Outdoor bronze sculptures are highly susceptible to corrosion in many environments and organic coatings are widely used for their protection. The purpose of this study was to determine the susceptibility of the commonly used coating Incralac to biodeterioration by microorganisms. A yeast was isolated from a bronze statue treated with Incralac and its ability to degrade Incralac was determined using growth curves, scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The organism grew slowly on Incralac in liquid culture, but SEM images demonstrated its ability to adhere to Incralac coated metal. Additionally, the yeast caused a rapid drop in the low frequency impedance of Incralac coated metal that was not observed under sterile conditions, indicating that the organism accelerated deterioration of the coating. The potential for microbial growth to accelerate deterioration of Incralac should be considered when developing a maintenance strategy for the protection of outdoor metal monuments. 相似文献
993.
C.D. Hurt 《Information processing & management》1985,21(3):177-186
This study examines the problem of identification of important authors in science by examining authors in the area of quantum mechanics. An examination was conducted using two methods of identification. The first method was a bibliometric approach and the second a historical approach. A gamma test of association was employed resulting in a finding of significant association between the ranks of authors. The major conclusion was that, when restricted to the same authors, the two methods of identifying important authors produce a statistically significant number of equivalent names. Discussion of the results and areas for further investigation are included. 相似文献
994.
995.
A predominant archery coaching tenet holds that the most effective means of releasing the bow string is by relaxation of the finger flexor muscles without activation of finger extensors. To evaluate the validity of this view, EMG patterns of the flexor digitorum superficialis and extensor digitorum muscles of the draw arm were examined using surface EMG electrodes in 15 highly skilled archers as each performed six shots. Each archer displayed consistent EMG patterns from shot-to-shot and two distinct flexor-extensor patterns were exhibited by the sample. The first, characterized by eight of the archers, supported the relaxation principle. For these archers, both flexor and extensor digitorum activity decreased markedly immediately prior to or at arrow release. The second pattern, characteristic of the remaining seven archers, contradicted the coaching tenet. While the flexor digitorum pattern was essentially the same as that described for the first pattern, the extensor digitorum displayed a marked increase in activity just prior to release, indicating that string release was facilitated by an active extension of the fingers. It was concluded that highly skilled archers do not predominantly reflect a release consistent with the coaching canon and that factors other than the string release mechanism discriminate the performances of skilled archers. 相似文献
996.
The effect of time of day on ratings of perceived exertion (RPE) at various intensities of cycling exercise, both below and above the ventilatory threshold, was studied in 32 subjects, 18 to 35 years of age. The ventilatory threshold occurred at the same (p greater than .05) mean (+/- SD) work rate in the morning (110.6 +/- 27.0 watts) and in the afternoon (111.9 +/- 23.9 watts) and was perceived as equally strenuous (p greater than .05) in the morning (RPE = 13.8 +/- 2.4) and in the afternoon (RPE = 13.6 +/- 2.8). At intensities below the ventilatory threshold, RPE was the same (p greater than .05) in the morning and in the afternoon; above the ventilatory threshold, RPE was lower (p less than .05) in the morning. We conclude that, during incremental submaximal cycling exercise above the ventilatory threshold, a particular work rate is perceived as less strenuous in the morning than in the afternoon. About 20% of this difference in RPE is explained by lower ventilatory demands in the morning. 相似文献
997.
NICOS D. POLYDORIDES 《European Journal of Engineering Education》1985,10(2):169-175
Engineering education has a long and satisfactory developmental history in Greece. On the other hand, industrial development, which is the product of systematic government policy of the post-war period, presents mixed results. It is a fact that engineering education, at least to the extent represented by formal, structured university curricula, has not been associated in any direct way with industry, for a variety of reasons—structural, economic, and administrative, originating both in industry and university. The scene appears to be changing in recent years, under pressure from many sides. It remains to be seen whether the long overdue convergence of the two systems will materialise in the near future. 相似文献
998.
999.
1000.
Cassandra Little Jill Packman Marlowe H. Smaby Cleborne D. Maddux 《Counselor Education & Supervision》2005,44(3):189-200
The authors evaluated the effectiveness of the Skilled Counselor Training Model (SCTM; M. H. Smaby, C. D. Maddux, E. Torres‐Rivera, & R. Zimmick, 1999) in teaching counseling skills and in fostering counselor cognitive complexity. Counselor trainees who completed the SCTM had better counseling skills and higher levels of cognitive complexity than did counselor trainees who did not receive the training. Before training, both experimental and control group participants overestimated their skills performance. The control group persisted in this overestimation after training, whereas students who completed the SCTM had a much more accurate self‐assessment. Results suggest that skills‐based training may improve counseling skills and cognitive complexity in counselor trainees. 相似文献