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排序方式: 共有267条查询结果,搜索用时 218 毫秒
151.
Ludman Evette J.; McBride Colleen M.; Nelson Jennifer Clark; Curry Susan J.; Grothaus Louis C.; Lando Harry A.; Pirie Phyllis L. 《Canadian Metallurgical Quarterly》2000,19(1):21
Perceived stress and depressive symptoms were examined as correlates and predictors of smoking cessation during pregnancy in a sample of 819 pregnant smokers (454 baseline smokers and 365 baseline quitters). Women who quit early in pregnancy had lower levels of stress and depressive symptoms than baseline smokers. Adjusting for level of addiction and other demographic factors related to stress and depressive symptoms eliminated the significant association between depressive symptoms and smoking cessation. Lower levels of stress and depressive symptoms were not predictive of cessation in later pregnancy. Prenatal healthcare providers should continue to assess level of addiction and provide targeted intensive cessation interventions. Interventions that reduce stress and depression may also be of benefit to women who are continuing smokers in early pregnancy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
152.
Lamar Melissa; Podell Kenneth; Carew Tania Giovannetti; Cloud Blaine S.; Resh Robynn; Kennedy Colleen; Goldberg Elkohnon; Kaplan Edith; Libon David J. 《Canadian Metallurgical Quarterly》1997,11(4):523
Perseverative behavior has not been extensively studied in patients with dementia. In this study, perseverative behavior was elicited with the dementia version of the Graphical Sequence Test. A control group and participants with Alzheimer's disease (AD) and subcortical ischemic vascular dementia (IVD) were studied. A factor analysis revealed a 3-factor model consisting of perseverations related to semantic knowledge, motor functioning, and a third, intermediary factor. IVD participants made more total perseverations than did AD participants. Perseverations made by AD participants were correlated with deficits on tests of semantic knowledge, whereas the perseverations made by IVD participants were correlated with motor and frontal systems tests. Results are consistent with the view that perseverative behavior is hierarchically arranged in terms of specific levels of cognitive complexity and the overall pattern of cognitive deficits associated with each type of dementia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
153.
Gruppuso Vincenza; Lindsay D. Stephen; Kelley Colleen M. 《Canadian Metallurgical Quarterly》1997,23(2):259
In L. L. Jacoby's (see record 1992-07943-001) 2-study-list process-dissociation (PD) procedure, recollection (R) is estimated by the difference in responding between including and excluding items from previously studied lists. Familiarity (F) is estimated with the estimate of R and equations representing the assumption that F and R are independent. The authors hypothesized that ability to exclude items from 1 list (and hence R and F) depends on similarity between lists. As predicted, R was greater and F was smaller when the 2 study lists were encoded with different tasks rather than the same task. Thus, R in the 2-study-list PD procedure does not necessarily involve retrieval of all attributes of the study episode, and F is not necessarily a completely undifferentiated feeling of oldness. Dividing attention at test (Experiment 2) or study (Experiment 3) dissociated F and R. Results are interpreted using a functionalist approach to recognition memory that combines aspects of dual-process and global memory models. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
154.
Jonathon D. MacIntyre Anthony K. Abu Peter J. Moss Daniel Nilsson Colleen A. Wade 《火与材料》2022,46(1):138-152
There is a risk of a building suffering unsustainable structural damage in the event of a large fire. Therefore, it is necessary to design buildings to withstand expected fires. A widely used simplified calculation method is the so-called “time-equivalence” method. There are significant concerns about the suitability of this method. This paper is part II of a twofold study examining the state of the art of time-equivalence methods. The purpose of this paper is to identify methods and/or analysis concepts which show the potential for use in modern design. A SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis is used for this purpose. However, as there is a large number of time-equivalence methods to assess, a numerical case study is first undertaken to identify methods which have sufficient accuracy to warrant further study. These analyses found that, while none of the time-equivalence methods studied have sufficient accuracy for use in their present form, the methods derived using the equal energy concept provide a good basis to model the effects of fire on a structure. This study recommends that a new time-equivalence method be developed using the equal energy approach. 相似文献
155.
The effects of small changes to the heat treatment temperature within the (α + β) phase field on the room temperature properties of a Ti-1.6 wt.%Fe-0.56 wt.%O-0.04 wt.%N alloy are described. To identify contributions from the individual alloying elements the binary Ti-1.6 wt.%Fe and ternary Ti-1.6 wt.%Fe-0.6 wt.%O and Ti-1.6 wt.%Fe-0.04 wt.%N alloys were also investigated. It was found that the interstitial elements affected the degree of disorder in the ωath phase, and that the magnitude of this disordering was not merely consistent with changes in Fe concentration. The strength and ductility of the alloys free of additional nitrogen were independent of annealing temperature, whereas the alloys containing nitrogen showed a marked dependency on the temperature. Alloys containing nitrogen displayed a prismatic rather than basal texture after processing. 相似文献
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158.
Carbon Dioxide Reforming of Methane with Pt Catalysts Using Microwave Dielectric Heating 总被引:4,自引:0,他引:4
Xunli Zhang Colleen S.-M. Lee D. Michael P. Mingos David O. Hayward 《Catalysis Letters》2003,88(3-4):129-139
Microwave heating was applied to the catalytic reforming reaction of methane with carbon dioxide over platinum catalysts. It was found that CO2 and CH4 conversions and the product selectivity (H2/CO) were generally higher under microwave conditions than that obtained with conventional heating at the same measured temperature. The effect of microwave heating was attributed to the formation of hot spots with higher temperature than that measured in the bulk catalyst bed. 相似文献
159.
The effects of a study/test mismatch in the viewing mode of natural scenes on recognition memory performance were examined. At both encoding and retrieval, scenes were presented either by being divided into quarters that were displayed in a sequential cumulative fashion or by scrolling the images through the screen, thereby gradually revealing the content of the images. Half of the participants were tested immediately after encoding and the other half after 48 hours. For both the immediate and delayed retrieval conditions, better recognition memory was demonstrated when viewing modes matched across study and test than when they mismatched. Implications for current processing and multiple systems views of memory are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
160.
Epstein Leonard H.; Paluch Rocco A.; Kilanowski Colleen K.; Raynor Hollie A. 《Canadian Metallurgical Quarterly》2004,23(4):371
Obese children were randomly assigned to a family-based behavioral treatment that included either stimulus control or reinforcement to reduce sedentary behaviors. Significant and equivalent decreases in sedentary behavior and high energy density foods, increases in physical activity and fruits and vegetables, and decreases in standardized body mass index (z-BMI) were observed. Children who substituted active for sedentary behaviors had significantly greater z-BMI changes at 6 (-1.21 vs. -0.76) and 12 (-1.05 vs. -0.51) months, respectively. Substitution of physically active for sedentary behaviors and changes in activity level predicted 6- and 12-month z-BMI changes. Results suggest stimulus control and reinforcing reduced sedentary behaviors are equivalent ways to decrease sedentary behaviors, and behavioral economic relationships in eating and activity may mediate the effects of treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献