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91.
Explicit memory declines with age while implicit memory remains largely intact. These experiments extended behavioral findings by recording event-related potentials (ERPs) in young and elderly adults during repetition priming and recognition memory paradigms. Words and pronounceable nonwords repeated after 1 of 3 delays. Stimuli were categorized as either word-nonword or old-new. Repeated items elicited more positive-going potentials in both tasks. Hemispheric asymmetries for word and nonword processing were observed during lexical decision: Repetition effects were larger over the left hemisphere for words and over the right hemisphere for nonwords. For the young, ERP repetition effects were larger during recognition memory. For old adults, conversely, repetition produced more positive-going waveforms during lexical decision. The elderly had ERP and behavioral deficits at long recognition delays. ERP repetition effects in the elderly, like behavioral performance, were preserved in an implicit task but impaired in an explicit memory task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Hopko Derek R.; Reas Deborah L.; Beck J. Gayle; Stanley Melinda A.; Wetherell Julie Loebach; Novy Diane M.; Averill Patricia M. 《Canadian Metallurgical Quarterly》2003,15(2):173
The assessment of worry among older adults typically has involved measures designed with younger cohorts. Because of special concerns in assessing older adults, modifications to existing instruments may be necessary. Addressing equivocal factor analytic data on the Penn State Worry Questionnaire (PSWQ) among younger adults, the authors conducted confirmatory factor analyses to evaluate the generalizability of previous models to older adults with generalized anxiety disorder. Data fit poorly with established single- and two-factor models. The single-factor model was modified, resulting in the elimination of 8 items, strong fit indices, high internal consistency, adequate test-retest reliability, and good convergent and divergent validity. Further psychometric work is required to assess whether the revised model is a more parsimonious method to assess late-life anxiety. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Assessed the association of young age at treatment, cranial irradiation, and time since treatment with intellectual deterioration among 49 long-term survivors of childhood leukemia. Ss had been randomized to receive low-dose cranial radiation therapy or high-dose chemotherapy. Longitudinal assessments of intellect were conducted. No significant effects of treatment group or age at treatment were detected. A small but statistically significant decline in mean full-scale IQ was noted over time (M?=?–3.6). Reanalysis with IQ test version included as a covariate eliminated IQ declines found initially. Results suggest that there has been reduced toxicity of these methods of treatment and that the magnitude and direction of error introduced by changing tests may approximate the magnitude of adverse effects on IQ expected from treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Lett Heather S.; Blumenthal James A.; Babyak Michael A.; Catellier Diane J.; Carney Robert M.; Berkman Lisa F.; Burg Matthew M.; Mitchell Pamela; Jaffe Allan S.; Schneiderman Neil 《Canadian Metallurgical Quarterly》2007,26(4):418
Objective: To compare the impact of network support and different types of perceived functional support on all-cause mortality or nonfatal reinfarction for patients with a recent acute myocardial infarction (AMI). Design: Participants were recruited from the Enhancing Recovery in Coronary Heart Disease (ENRICHD) trial; 2,481 AMI patients with depression or low social support were randomized to a cognitive-behavioral intervention or to a usual care control group. Data collection for certain measures of social support was limited: 2,466 participants completed the ENRICHD Social Support Inventory; 2,457 completed the Perceived Social Support Scale; 1,296 completed the Social Network Questionnaire; and 707 completed the Interpersonal Support and Evaluation List, Tangible Support subscale. Patients also completed the Beck Depression Inventory and were followed for up to 4.5 years. Main Outcome Measure: Time to death or nonfatal reinfarction. Results: Over the follow-up period, 599 patients (24%) died or had a nonfatal AMI. Survival models controlling age, sex, race, socioeconomic status, smoking, antidepressant use, and a composite measure of increased risk revealed that higher levels of perceived social support were associated with improved outcome for patients without elevated depression but not for patients with high levels of depression. Neither perceived tangible support nor network support were associated with more frequent adverse events. Conclusion: AMI patients should be assessed for multiple dimensions of perceived functional support and depression to identify those at increased psychosocial risk who may benefit from treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Morrison Diane M.; Golder Seana; Keller Thomas E.; Gillmore Mary Rogers 《Canadian Metallurgical Quarterly》2002,16(3):212
The theory of reasoned action (TRA) is used to model decisions about substance use among young mothers who became premaritally pregnant at age 17 or younger. The results of structural equation modeling to test the TRA indicated that most relationships specified by the model were significant and in the predicted direction, Attitude was a stronger predictor of intention than norm, but both were significantly related to intention, and intention was related to actual marijuana use 6 months later. Outcome beliefs were bidimensional, and positive outcome beliefs, but not negative beliefs, were significantly related to attitude. Prior marijuana use was only partially mediated by the TRA variables; it also was directly related to intentions to use marijuana and to subsequent use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
The effect of low temperature blanching on firmness of eight vegetables was studied. Preheating vegetables at low temperatures prior to a conventional blanch resulted in firmer products. Temperature and time had significant effects on texture, with temperature the most influential. Under optimal conditions, firmness improvements in preheated vegetables as compared to blanched controls were: Bok choy—3.0 × (65 °C, 45 min); Chinese cabbage—1.8 × (55 °C, 45 min); cabbage—1.6 × (65 °C, 15 min); green bell peppers—1.36 × (70 °C, 15 min); sugar snap peas—1.7 × (65 °C, 30 min); carrots—2.1 × (60 °C, 15 min) and broccoli—2.9 × (60 °C, 15 min). Thermal stability and optimal temperature for pectin methylesterase in homogenates from these vegetables were also analyzed. The relationship between optimum preheating conditions for textural integrity and pectin methylesterase activity is discussed. 相似文献
97.
98.
Diane E.Davis 《国外城市规划》2006,21(6):112-120
学者们研究全球背景中的城市几乎与研究城市的时间一样长(Weber.1927:Pirenne.1936)。在早期有关城市的作品中.”全球城市”的概念未必使用过.但是国际金融市场联系与贸易关系却是存在的。在许多早期作品中.城市的物质、社会和经济变迁与国家和国际的政治环境——从封建专制主义秩序的灭亡(weber.1958)到现代民族国家的兴起(Tilly.1975;1990)——以及现代性的社会关系(Durkheim.1993:Simmel,1950)的出现紧密相连. 相似文献
99.
A review of the literature on ethnocultural identity and eating disorders indicates a relationship between conflicted identity and eating disturbance. This article discusses that relationship by suggesting that eating disorders represent internalized means of oppression for women of color. Difficulties in diagnosis and treatment of eating disorders in women of color are identified. Suggestions for ways in which diagnosis, assessment, and treatment of eating disorders may become more culturally relevant and effective are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Effect of grain-boundary crystallization on the high-temperature strength of silicon nitride 总被引:1,自引:0,他引:1
Laurie A. Pierce Diane M. Mieskowski William A. Sanders 《Journal of Materials Science》1986,21(4):1345-1348
Si3N4 specimens having the composition 88.7 wt% Si3N4-4.9wt% SiO2-6.4wt% Y2O3 (85.1 mol% Si3N4-11.1 mol% SiO2-3.8mol% Y2O3) were sintered at 2140° C under 25 atm N2 for 1 h and then subjected to a 5 h anneal at 1500° C. Crystallization of an amorphous grainboundary phase resulted in the formation of Y2Si2O7. The short-time 1370° C strength of this material was compared with that of material of the same composition having no annealing treatment. No change in strength was noted. This is attributed to the refractory nature of the yttrium-rich grain-boundary phase (apparently identical in both glassy and crystalline phases) and the subsequent domination of the failure process by common processing flaws.Chemical analysis of the medium indicated 5.25 wt% O2, 0.46 wt% C, 0.8 wt% Al, and expressed in p.p.m. 670 Ca, 30 Cu, 2000 Fe, <2 Ti, 370 Cr, 130 Mg, 90 Mn, <10 V, <20 Zr, 2000 Mo, 240 Ni, 130 Zn, <30 Pb, <60 Sn. 相似文献