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921.
This study examined the effect of rest breaks on traffic accidents by 720 randomly selected professional drivers who completed a postal questionnaire. Drivers involved in an accident preferred to enjoy their breaks at rest places meant for professional drivers, whereas accident-free drivers chose more freely the timing of their breaks during driving.  相似文献   
922.
To study the relationship between visual perception of magnitude of wrinkles and geometrical parameters of surfaces, four potentially relevant parameters of the surface profile were considered: the variance (sigma2), the cutting frequency (Fc), the effective disparity curvature (Dce) of the wrinkled surface over the eyeball distance of the observer, and the frequency component of the disparity curvature (Dcf). Analysis of garment seams with varying amount of pucker showed that, while the logarithm for each of these four parameters has a strong linear relationship with the visually perceived magnitude of wrinkles, following the Fechner Law, the effective disparity curvature (Dce) and the frequency component of the disparity curvature (Dcf) with visual perception appeared stronger. This modeling may be an objective method for measuring magnitude of surface wrinkles.  相似文献   
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926.
On March 11, 2004, Al-Qaeda set off 10 bombs on several train routes in Madrid. 192 people were killed and 2,000 wounded. In this study, 1,179 questionnaires were administered Week 2 after the attacks to residents 18 years and over from the affected geographical areas. The questionnaire included items about sociodemographic variables and exposure to the attacks. Psychological effects were assessed as presence of acute stress and depressive symptomatology and functional impairment. 46.7% of the sample presented symptomatology of acute stress and 49.6% depressive symptoms. Among the symptoms of acute stress, the most frequent were re-experiencing (72.5%) and dissociative symptoms (71.8%). The chief predicting variables in symptomatology were being female, over 65 yr. old, and a habitual train user. The large number of affected people was refined with an item analysis and the consideration of severity of interference in psychosocial functioning.  相似文献   
927.
Confirmatory factor analysis examined the factor structure of DSM IV Attention Deficit Hyperactivity Disorder symptoms and analyzed the differences in informants' ratings of ADHD symptoms by children's age and sex. A sample of 1,018 Spanish school children, 574 girls and 444 boys, ages 4 to 12 years, was rated by teachers and parents. Confirmatory factor analysis showed a similar fit for the three-factor model of Inattention, Hyperactivity, and Impulsivity (teachers: CFI = .976, RMR = .041, % of total variance = 83.2; parents: CFI = .969, RMR = .037, % of total variance = 82.7) and for the two-factor model of Inattention and Hyperactivity Impulsivity (teachers: CFI = .958, RMR = .044, % of total variance = 79.3; parents: CFI = .961, RMR = .038, % of total variance, 79.9). The two-factor model was selected as a parsi monious representation of the teachers' and parents' ratings of ADHD symptoms. Analyses of variance indicated significant differences in teachers' and parents' mean ratings across sex and school grades of children.  相似文献   
928.
According to the Indian Health Service, substance abuse and Type 2 diabetes are serious problems among Native Americans. To assess substance use in a medical setting, valid screening tests are needed so the Alcohol Use Disorders Identification Test (AUDIT), a simple brief screen for excessive drinking, and the CAGE-adapted to Include Drugs (CAGE-AID) for identifying primary care patients with alcohol and drug disorders were given 50 Northern Plains American Indians with diabetes. Both are short, easy to administer, have good sensitivity and specificity, and can be easily incorporated into a medical history protocol or intake procedure. Reliability coefficients were above .90 and appeared to have sufficient concurrent and divergent validity indicated by moderate correlations with the General Well-being Schedule (rs=-.39 and -.36), the Family-Adaptation, Partnership, Growth, Affection, & Resolve (r =-.47 and -.36), and the Beck Depression Inventory-IT (r = .36 and .29).  相似文献   
929.
This study examined sex differences and age-related changes in mathematics based on Eccles's 1985 expectancy-value model of "achievement-related choices" and Dweck's 1986 motivation-process model. We have assessed motivational variables and performance in mathematics for youth in Grades 5, 7, and 9 in a German comprehensive secondary school. Significant sex differences in Grades 7 and 9 were observed even when school marks were controlled for. Furthermore, the results indicated differences between Grade 7 and Grade 9 on most of the motivational variables. Older students show a less favorable motivational pattern. Our results give evidence of the importance of motivational encouragement in mathematics classes, especially for girls and low achieving learners.  相似文献   
930.
The relationships between age-specific suicide mortality rates and social life factors for all 47 Japanese prefectures in 1980, 1985, and 1990 were assessed by multiple regression analysis after factor analysis on 20 social life indicators. During this period, Japan experienced a secondary oil crisis in 1980-1983 and a bubble economy in 1986-1990. It was concluded that (1) low income was the major determinant which positively affected suicide mortality rate in middle-aged men during a previous 20-yr. period (1970-1990), (2) urbanization was negatively associated with male suicide mortality rates in most of the age classes in the 1980s, (3) unemployment was one of the major determinants of increased suicide mortality rate in middle-age men in the 1980s, and (4) unemployment was the major factor which was inversely associated with suicide mortality rate for elderly women from 1980 to 1990 in Japan.  相似文献   
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