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41.
Data from the National Institute of Child Health and Human Development Study of Early Child Care were analyzed to explore effects of marital separation on children in the first 3 years of life. The sample included 73 never-married mothers and 97 separated mothers; a comparison group of 170 was conditionally randomly selected from the 2-parent families. Children in 2-parent families performed better than children in 1-parent families on assessments of cognitive and social abilities, problem behavior, attachment security, and behavior with mother. However, controlling for mothers' education and family income reduced these differences, and associations with separated-intact marital status were nonsignificant (the effect size was .01). Thus, children's psychological development was not affected by parental separation per se; it was related to mothers' income, education, ethnicity, childrearing beliefs, depressive symptoms, and behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
The phenomenon of nanohillock-like defect formation on the surfaces of CR-39 by ultra-short laser irradiation is investigated using an Atomic Force Microscope (AFM) and Raman Scattering. A polymer CR-39 target was exposed to Ti:sapphire 25-fs laser pulses with a central wavelength at 800 nm. Samples were irradiated for different laser fluences both in air and vacuum. Detailed surface topographical features of the bombarded samples were characterized by atomic force microscopy in contact mode in air at room temperature. AFM reveals that the growth of nanohillocks and their features are strongly dependent on the ambient condition, target position from focus, and irradiation fluence. The appearance of these nanohillocks in the range 1–20 nm in height and 10–90 nm in diameter are regarded as typical features for fast electronic processes (correlated with existence of hot electrons) and are explained on the basis of Coulomb explosion. These nanostructures due to localization of laser energy deposition in small areas provide a possible pathway from dense electronic excitation to atomic motion causing permanent structural modification which are well correlated to structural alterations, like crosslinking and chain scissions, inferred from Raman spectroscopy.  相似文献   
43.
Seven experiments assessed the hypothesis derived from terror management theory that reminding people of their mortality would increase accessibility of constructs central to their worldview. Experiment 1 found that mortality primes, relative to control primes, increased accessibility of nationalistic constructs for men but not for women. Experiment 2 replicated this finding and also found that mortality salience increased romantic accessibility for women but not for men. Four subsequent experiments supported the role of unconscious death-related ideation in producing these effects. A final experiment demonstrated that situational primes can increase the accessibility of nationalistic constructs for women after mortality salience. The roles of situational cues and individual differences in the effects of exposure to death-related stimuli on worldview-relevant construct accessibility are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
44.
The authors conducted a comparative test of the hypotheses that (a) stress is an etiological factor for smoking and (b) cigarette smoking causes increases in stress (A. C. Parrott, 1999). Participants were a sample of 1,364 adolescents, initially surveyed at mean age 12.4 years and followed at 3 yearly intervals. Measures of negative affect, negative life events, and cigarette smoking were obtained at all 4 assessments. Latent growth modeling showed negative affect was related to increase in smoking over time; there was no path from initial smoking to change in negative affect. Comparable results were found for negative life events, with no evidence for reverse causation. Results are discussed with respect to theoretical models of nicotine effects and implications for prevention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
45.
Aging and movement: Variability of force pulses for saccadic eye movements.   总被引:1,自引:0,他引:1  
Age-related differences in the trajectories of saccadic eye movements were examined. Younger and older adult subjects produced saccades to predictable target locations. Detailed features of the movements were examined such as the time of peak acceleration and the variability in the magnitude of the peak velocity. These and other measures reveal important details of the force pulses underlying the eye movements and the mental mechanisms that control them. Although minor differences were apparent between the eye movements of younger and older adults, the general patterns were the same across age groups. These results suggest that fundamental details of the brain mechanisms involved in the control of movement are the same for younger and older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
46.
Much of the present research on the physiological effects of dietary fiber and starch has been done on sources isolated from the parent material, and it is not clear whether they have the same effects if fed in the intact or whole grain. For dietary fiber, physiological effect depends on extent of fermentation in the large intestine, and this is influenced by chemical composition, solubility, physical form, and presence of lignin or other compounds. All of these factors are altered by isolation of a fiber source from the whole grain, and hence effects of eating fiber vary. Similarly, physical form and presence in the whole grain will affect digestibility of starch in the small intestine, which in turn influences the glycemic response and colonic effects determined by the extent of malabsorption and entry into the colon. Starch that enters the colon is fermented and produces short‐chain fatty acids, particularly butyrate, which is necessary to maintain a healthy mucosa. Hence, their presence within the whole grain may have important implications for health for both dietary fiber and starch. Evidence indicates that such effects are beneficial and that whole‐grain consumption should be encouraged.  相似文献   
47.
48.
Job postings and the decision to interview: A verbal protocol analysis.   总被引:1,自引:0,他引:1  
Investigated the process of deciding whether or not to apply for jobs, using the verbal protocol analysis (VPA) technique. Verbal reports provided by participants as they evaluated job postings and decided whether or not to interview for jobs were analyzed to assess what information was heeded, the impact of incomplete or unusual information, and the role of inferences regarding job characteristics and probability of hire. Results indicated that location and compensation received the most attention and that participants also responded to the amount of information provided. In addition, participants made inferences about unobserved characteristics and probability of hire, although the latter played little role in the decision to interview. The study also provided support for the usefulness of VPA by demonstrating that neither the verbal protocol process nor the use of prompts significantly influenced participants' decisions (as compared with the decisions of control groups). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
The psychological functioning and behavior of 46 sexually abused girls (ages 6–14) was compared with that of 46 nonabused girls who were matched on age, race, family income, and family constellation. Sexually abused children demonstrated heightened sexual preoccupation and behavior problems, lower cognitive abilities and school achievement, and more stressful past histories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
Conducted a study with 120 externally and 120 internally oriented 4th graders (as measured by the Intellectual Achievement Responsibility Scale) to examine the modifiability of children's information-processing strategies. Ss observed a constraint-seeking model or a change (contrasting response patterns) model which provided either minimal or augmented verbal cues and associated reinforcement contingencies. Ss in augmented modeling conditions required fewer questions to reach a solution and asked a higher proportion of constraint-seeking questions relative to the nonaugmented and no-model control groups. The effects of augmentation were more pronounced for the constraint-seeking than for the change model. Internals in augmented conditions required fewer questions to solution and asked a higher proportion of constraint-seeking questions than did externals, but there were no significant differences between internals and externals in nonaugmented conditions. The major findings on the immediate posttest were maintained on a transfer task administered 1 wk later, demonstrating the short-term stability and generality of the modeling effects. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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