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91.
Morgan Thomas J.; Morgenstern Jon; Blanchard Kimberly A.; Labouvie Erich; Bux Donald A. 《Canadian Metallurgical Quarterly》2004,18(4):316
Urges to use substances is an important construct in understanding the maintenance of substance use as well as relapse. There is a need to evaluate single instruments measuring global urges to use substances (including alcohol). The Obsessive Compulsive Drinking Scale (OCDS; R. F. Anton, D. H. Moak, & P. Latham, 1995) was revised and tested as a single measure of urges to use substances. Participants were 252 adults entering outpatient substance abuse treatment. Results suggest that the revised scale (OCDS-R) primarily assesses 1 global factor for urges to use substances. In addition, strong support was found for the reliability and concurrent validity of the OCDS-R, although results for its predictive validity were mixed. The OCDS-R is a brief, psychometrically sound self-report instrument that has applicability within clinical and research settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In the synchrony judgment paradigm, Ss judge whether a click precedes or follows the onset of a light flash and, on other trials, whether or not a click precedes light termination. The interclick interval defines the duration of visible persistence. An elaboration of this method was developed that consisted of 2 phases: In Phase 1, the luminance of a reference stimulus was psychophysically matched to the peak brightness of the test flash. Five luminance values between .1 and 1.0 of the reference stimulus were used subsequently. In Phase 2, a random 1 of the 5 reference stimuli, a test flash, and a click were presented; the Ss judged whether the click occurred before or after the brightness of test flash reached the reference value (on onset trials) or decayed below it (on termination trials). This method was validated on 3 male graduate students with test stimuli whose luminance rose and decayed slowly in time, and then was used to trace out the precise subjective rise and decay (temporal brightness response function) of brief flashes. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Hydrocarbon gases produced during in vitro peroxidation of polyunsaturated fatty acids and decomposition of preformed hydroperoxides 总被引:13,自引:0,他引:13
Hydrocarbon gases have been used previously as an index of lipid peroxidation in vivo and in vitro. In vitro experiments are
reported on the formation of hydrocarbon gases from peroxidizing ω-3 and ω-6 fatty acids. Hydrocarbon gases were not related
during a 20-hr peroxidation phase but were released following the decomposition of hydroperoxides by addition of excess ascorbic
acid. The major hydrocarbon gas products in iron, copper, or hematin catalyzed peroxidation systems were ethane or ethylene
from linolenic acid, and pentane from linoleic acid and arachidonic acid. Calculations of the ratios of hydrocarbon gases
formed were based on fatty acid decrease and/or change in diene conjugation and peroxide values. Depending on the fatty acid,
catalyst, and calculation basis used, pentane formation was a high as 1.3 mol %, ethanol 4.3 mol %, and ethylene 10.6 mol
%. 相似文献
100.
Erich Wimmer 《Journal of Computer-Aided Materials Design》1994,1(3):215-242
Summary Present theoretical and computational approaches, combined with the impressive advances in computer hardware and software, open the possibility for materials design from first principles. This article presents a perspective on the relevant developments in computational chemistry, solid state physics and statistical mechanics and it assesses the merits and limitations of Hartree-Fock, density functional, semiempirical and force field approaches in terms of six criteria: capability, generality, accuracy, accessible system size, accessible time scales and computational efficiency. Functional materials for microelectronic, optical and magnetic applications currently present better opportunities for first-principles approaches than structural materials, where atomistic approaches, despite some encouraging results, are still far from capturing the full complexity of the dynamics involved in mechanical, thermal, diffusive and corrosive behavior. 相似文献