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211.
In a survey of 48 men and 61 women from a southwestern US college, the gender difference in reported number of sex partners was mediated by the degree to which individuals felt that men and women who had many sexual partners were prestigious. In addition, men cared about the quantity and quality of their sex partners more than women did and these two factors were also related to reported number of sexual partners. The gender difference in reported sex partners is not veridical; it can be accounted for with attitudinal measures related to status and sex that are more common in men than women. Results are discussed in terms of understanding biased reporting in young American men and women.  相似文献   
212.
The developmental experiences of very young American Indian children today are not well documented in the current literature. The present study sought to explore the social‐emotional development of American Indian toddlers living on a Northern Plains reservation, as a function of maternal variables. Mothers completed self‐report questionnaires about their experiences and their children's development. Observer ratings of children's development also were conducted. Maternal stress, substance use/abuse, perceptions of stress in the mother–child relationship, social support, and American Indian cultural identity were significantly related to children's social‐emotional development. This study is the first to explore these relationships in a Northern Plains American Indian sample of young children and their mothers. Results suggest possible points of intervention for improving the developmental outcomes of very young American Indian children.  相似文献   
213.
Preservice teachers learn evidence-based practices in university classrooms but often fail to use them later on in their own K-12 classrooms. The problem may be a missing link in teacher preparation, i.e., failure to teach preservice teachers to generalize newly acquired techniques. Two experiments using multiple baseline designs across participants assessed effectiveness of a model to promote generalization and maintenance of a specific teaching skill. In Experiment 1, preservice teachers’ maintenance of behavior deteriorated from practicum to student teaching when intervention consisted of training to criteria alone. When a programming for generalization component (program common stimuli) was added to the intervention, teachers in Experiment 2 generalized and maintained behavior across settings (student teaching to own classrooms) at a higher average than occurred during intervention.  相似文献   
214.
In this article, an automated and accurate mouse observation method, based on a conventional test for motor function evaluation, is outlined. The proposed measurement technique was integrated in a regular open-field test, where the trajectory and locomotion of a free-moving mouse were measured simultaneously. The system setup consisted of a transparent cage and a camera placed below it with its lens pointing upward, allowing for images to be captured from underneath the cage while the mouse was walking on the transparent cage floor. Thus, additional information was obtained about the position of the limbs of the mice for gait reconstruction. In a first step, the camera was calibrated as soon as it was fixed in place. A linear calibration factor, relating distances in image coordinates to real-world dimensions, was determined. In a second step, the mouse was located and its body contour segmented from the image by subtracting a previously taken “background” image of the empty cage from the camera image. In a third step, the movement of the mouse was analyzed and its speed estimated from its location in the past few images. If the speed was above a 1-sec threshold, the mouse was recognized to be running, and the image was further processed for footprint recognition. In a fourth step, color filtering was applied within the recovered mouse region to measure the position of the mouse’s paws, which were visible in the image as small pink spots. Paws that were detected at the same location in a number of subsequent images were kept as footprints—that is, paws in contact with the cage floor. The footprints were classified by their position relative to the mouse’s outline as corresponding to the front left or right paw or the hind left or right paw. Finally, eight parameters were calculated from the footprint pattern to describe the locomotion of the mouse: right/left overlap, front/hind base, right/left front limb stride, and right/left hind limb stride. As an application, the system was tested using normal mice and mice displaying pentobarbital-induced ataxia. The footprint parameters measured using the proposed system showed differences of 10% to 20% between normal and ataxic mice.  相似文献   
215.
An important focus of recent aggression research has been to identify personality variables that influence the expression of aggression. One such variable may be anxiety sensitivity (AS). Individuals high in AS fear unpleasant anxiety-related physiological sensations and perhaps physiological arousal in general. Accordingly, people high in AS are motivated to avoid situations that produce these sensations. With respect to aggressive encounters, an intense attack by an opponent involves significant physiological arousal. High anxiety-sensitive individuals may therefore attempt to decrease the intensity of the interaction by responding in a non-aggressive or conciliatory manner. To test this possibility, 112 community volunteers completed a measure of AS and a well-validated laboratory task designed to assess aggressive behavior. As predicted, an inverse relation between AS and extreme aggressive responding was found. Specifically, as AS increases, retaliatory aggression is less likely after intense attack by an opponent.  相似文献   
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Assessment of a patient after hospital‐treated self‐harm or psychiatric hospitalization often includes a risk assessment, resulting in a classification of high risk versus low risk for a future episode of self‐harm. Through systematic review and a series of meta‐analyses looking at unassisted clinician risk classification (eight studies; N = 22,499), we found pooled estimates for sensitivity 0.31 (95% CI: 0.18–0.50), specificity 0.85 (0.75–0.92), positive predictive value 0.22 (0.21–0.23), and negative predictive value 0.89 (0.86–0.92). Clinician classification was too inaccurate to be clinically useful. After‐care should therefore be allocated on the basis of a needs rather than risk assessment.  相似文献   
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Effects of adult age and working memory on reasoning and spatial abilities   总被引:3,自引:0,他引:3  
Three predictions were derived from the hypothesis that adult age differences in certain measures of cognitive functioning are attributable to age-related reductions in a processing resource such as working-memory capacity. Each prediction received at least some degree of empirical support in a study involving 120 males ranging between 20 and 79 years of age. First, older adults exhibited greater impairments of performance than did young adults when task complexity increased and more demands were placed on the limited processing resources; second, the magnitudes of these complexity effects were highly correlated across verbal (reasoning) and spatial (paper folding) tasks. Finally, statistical control of an index of a working-memory processing resource attenuated the effects of age on the measures of cognitive performance. It was concluded that further progress in understanding the mechanisms of the relation between age and cognitive functioning will require improved conceptualizations of the nature of working memory or other hypothesized mediating constructs.  相似文献   
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