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151.
Coonfield Daniel L.; Kiefer Stephen W.; Ferraro Frank M. III; Sinclair John David 《Canadian Metallurgical Quarterly》2004,118(5):1089
Three experiments examined the effect of acute naltrexone treatment on both taste reactivity and consumption of ethanol in high ethanol-preferring rat lines: Alko Alcohol-Accepting (AA) rats (Experiments 1 and 2) and Alcohol-Preferring (P) rats (Experiment 3). A 3.0 mg/kg naltrexone dose was ineffective at altering ethanol palatability for either line, whereas 7.5 mg/kg was effective at reducing palatability of 10% ethanol for AA, but not P, rats, as reflected by both a decrease in ingestive responding and an increase in aversive responding. The effects of naltrexone on ethanol consumption were quite consistent: At both dosages, acute naltrexone treatment significantly decreased consumption of 10% ethanol. Termination of naltrexone resulted in an immediate increase in ethanol consumption to control levels. Results show that ethanol palatability and consumption can be dissociated in the rat and that the organization of opioidergic mechanisms that mediate ethanol responses may vary between rat lines. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
152.
Hufford Michael R.; Shields Alan L.; Shiffman Saul; Paty Jean; Balabanis Mark 《Canadian Metallurgical Quarterly》2002,16(3):205
A. A. Stone and S. Shiffman (1994) defined ecological momentary assessment (EMA) as monitoring or sampling strategies that assess phenomena at the moment they occur in natural settings, thus maximi7ing ecological validity while avoiding retrospective recall. To address the extent to which EMA affects the behavior and cognitions under observation, the authors examined behavioral and motivational reactivity to EMA among male and female undergraduate problem drinkers (n = 33). Participants completed a 2-week monitoring protocol using palmtop computers as well as pre- and postmonitoring measures of their drinking behavior and motivation for change. The findings suggest that the magnitude of reactivity to EMA is small. Suggestions for future research Are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
153.
1 IntroductionAnumber of high-energy heterocyclic and carbocyclicsubstances have been prepared and characterized[1,2]aspotential substitutes for 1,3,5,7-tetranitro-1,3,5,7-tet-razocane(HMX),2,4,6-triamino-1,3,5-trinitrobenzene(TATB)and 2,2′,4,4′,6,6′-hexanitrostilbene(HNS)inweapon systems[1,2]and downhole well[3-5]applications.2,4,6,4′,6′,2″,4″,6″-Octanitro[1,1′,3′,1″]-terphenyl(ONT)[6,7]and 2,2′,2″,4,4′,4″,6,6′,6″-nonanitro[1,1′,3′,1″]-terphenyl(NONA)[8,9].belong amo… 相似文献
154.
Forcier Kathleen; Stroud Laura R.; Papandonatos George D.; Hitsman Brian; Reiches Meredith; Krishnamoorthy Jenelle; Niaura Raymond 《Canadian Metallurgical Quarterly》2006,25(6):723
A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
155.
Peeters Frenk; Nicolson Nancy A.; Berkhof Johannes; Delespaul Philippe; deVries Marten 《Canadian Metallurgical Quarterly》2003,112(2):203
Major depressive disorder (MDD) is characterized by high negative affect (NA) and low positive affect (PA), but little is known about emotional reactivity in daily life. The authors used experience sampling methodology to investigate changes in NA and PA following minor daily events in MDD compared with healthy participants. Contrary to expectation, MDD participants did not report more frequent negative events, although they did report fewer positive events. Multilevel regression showed that both NA and PA responses to negative events were blunted in the MDD group, whereas responses to positive events were enhanced. NA responses to negative events persisted longer in MDD participants. Depressed participants with a positive family history or longer current episodes showed relatively greater NA responses to negative events. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
156.
Children's emotional regulation (as indexed by vagal suppression) and children's emotional reactivity during an argument were examined as moderators and mediators of parental problem drinking and children's adjustment in a sample of 6- to 12-year-olds. Cardiac vagal tone was assessed during both a baseline condition and exposure to an audiotaped argument. Vagal suppression was calculated by subtracting vagal tone during the baseline from that recorded during the argument, with a higher number representing increased suppression of vagal tone during the argument. Emotional reactivity was based on both observations of overt behaviors of children and their reported feelings during the argument. A higher level of vagal suppression was a protective factor against children's externalizing, internalizing, and social problems associated with exposure to parental problem drinking. Emotional reactivity was a vulnerability factor, and children's increased anger and fear, and to a lesser degree sadness, each moderated and exacerbated the effects of parental problem drinking on child outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
157.
We study isothermal oxidation of laser welded FeCrAl-RE samples containing specific fractions of seams in a bead-on-plate configuration at approximately 900°C using thermogravimetric analysis (TGA), field emission scanning electron microscope (FEG-SEM), transmission electron microscope (TEM), electron probe microanalysis (EPMA) techniques. An important reduction in the alumina-growth rate over the fusion zone compared to the base material occurs at 900°C, thereby, suppressing the discontinuous increase in mass gain commonly observed for alumina-forming alloys when the temperature decreases from 1000°C to 900°C. This phenomenon is mainly related to the concomitant dramatic chromium carbide precipitation at the fusion zone/oxide film interface and possible earlier injection of the rare earth elements into the oxide layer. On one hand, chromium carbide precipitation, which is linked to the laser melting-induced high free carbon, contributes to improve the effectiveness of the diffusion barrier provided by the thermally growing scale. On the other hand, due to their initial high enrichment at the fusion zone surfaces, rare earth elements can penetrate in the oxide layer and promote the elimination of detrimental phase transformation of metastable platelets (γ,θ-Al2O3) to α-Al2O3 during the initial stages of oxidation. 相似文献
159.
采用多种检测方法对某水电工程骨料碱活性进行了研究。岩相法检测结果表明,6个骨料样品中含有一定量的隐晶状石英和隐晶状玻璃质,这两种成分具有潜在的碱-硅酸反应活性。对于XJ-2骨料样品:砂浆棒快速法试验结果表明,该骨料为具有潜在碱-硅酸反应活性的骨料;混凝土棱柱体快速法和混凝土棱柱体法试验结果表明,该骨料属于后期膨胀较快的骨料。对于XJ-4骨料样品:混凝土棱柱体法试验结果表明,棱柱体试件一年膨胀率接近0.04%限值,且试件膨胀率仍继续发展,该骨料也属于后期膨胀较快的骨料,建议给予关注。研究结果为准确判定骨料的碱活性提供了技术支持,为保证工程质量奠定了基础。 相似文献
160.