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61.
In a prospective study of adolescent depression, adolescents (N?=?1,508) were assessed at Time 1 and after 1 yr (Time 2) on psychosocial variables hypothesized to be associated with depression. Most psychosocial variables were associated with current (n?=?45) depression. Formerly depressed adolescents (n?=?217) continued to differ from never depressed controls on many of the psychosocial variables. Many of the depression-related measures also acted as risk factors for future depression (n?=?112), especially past depression, current other mental disorders, past suicide attempt, internalizing behavior problems, and physical symptoms. Young women were more likely to be, to become, and to have been depressed. Controlling for the psychosocial variables eliminated the gender difference for current and future but not for past depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Reviews the research concerning the possible functional roles of the prosodic aspects of infant-directed speech ("baby-talk"), and shows that this style of speaking could have both attentional and affective functions (in addition to linguistic ones). Studies of other speech registers could profit from taking similar approaches and even using similar techniques to those used in infant-directed speech research to tease apart the linguistic, attentional, and affective components of these other speaking styles. Nursing-home register is used to exemplify the importance of examining the social, emotional, and linguistic ramifications of a communication style separately. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Encompassing such versatile analytical techniques as scanning tunneling microscopy and atomic (or scanning) force microscopy, scanning probe microscopes produce high-resolution three-dimensional images. Because of their power as quantitative tools for three-dimensional surface measurement and analysis, the techniques are being used in materials science and engineering for the study of a variety of advanced materials and for investigations into numerous phenomena, including reaction chemistry, crystallinity, kinetics, equilibrium processes, tribology, and conductivity.  相似文献   
65.
The Revised Memory and Behavior Problems Checklist (RMBPC), a 24-item, caregiver-report measure of observable behavioral problems in dementia patients, provides 1 total score and 3 subscale scores for S problems (memory-related, depression, and disruptive behaviors) and parallel scores for caregiver reaction. Data were obtained from 201 geriatric Ss and their caregivers. Factor analysis confirmed 3 1st-order factors, consistent with subscales just named, and 1 general factor of behavioral disturbance. Overall scale reliability was good, with alphas of .84 for S behavior and .90 for caregiver reaction. Subscale alphas ranged from .67 to .89. Validity was confirmed through comparison of RMBPC scores with well-established indexes of depression, cognitive impairment, and caregiver burden. The RMBPC is recommended as a reliable and valid tool for the clinical and empirical assessment of behavior problems in dementia Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
The colour stability of juice and purées made from a mixture of two strawberry varieties, stored at + 20°C or at –20°C under aerobic and anaerobic conditions, was studied. High-performance liquid chromatography and spectrophotometric analysis were used to monitor the changes in colour during storage. Pelargonidin 3-glucoside comprised 80% of the total anthocyanin content. Four other pelargonidin-based peaks were found, being 10.4%, 3.5%, 0.7% and 0.3% of the total and two cyanidin peaks were present, being 3.3% and 0.4% of the total. Clarification before storage caused considerable losses in the initial anthocyanin concentrations. Storage conditions (air versus nitrogen) did not influence the rate of loss of anthocyanins during storage or the formation of polymeric pigments. There were no losses in anthocyanins and no increase in the amount of colour measured at 510 nm due to polymers in samples stored at–20°C. Polymerisation occurred in the samples stored at + 20°C, especially in the clarified samples.  相似文献   
67.
The hypothesis that orienting visual attention is an important component of visual curve tracing was investigated. Ss examined a visual display and decided as quickly as possible whether 2 dots were on the same or different curves. The rate of tracing was determined by measuring the effects of curve distance on response time. Attention was directed to a curve by momentarily presenting it at a higher luminance. Directing attention to a curve that had 2 dots on it resulted in faster tracing rates with large benefits in overall response time. Directing attention to a distractor curve resulted in slower tracing rates and sizable costs in overall response times. Two alternative nonattentional explanations (eye movements and visible persistence) were examined and rejected. The role of attention in curve tracing is discussed in terms of the selective nature of curve tracing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
This paper investigates spatial effects in a generalized least-squares regression model for small-area social indicators. The significance of using spatial correlation in addition to an intermediate weighting (allowing for sampling and extraneous variation in the indicator) differs according to the index analyzed. It is greater for small-area fertility (over 758 London wards) than for small-area mortality. The model is extended to include serial as well as spatial correlation, then to spatial forecasting. The analyses show that the extent of spatial correlation can vary considerably according to (a) the specification of the form of spatial interaction, and (b) which independent variates are included. Further, spatial effects can be much reduced by including serial correlation.  相似文献   
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