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181.
182.
Michelle C. Sarche Calvin D. Croy Cecelia Big Crow Christina M. Mitchell Paul Spicer 《Infant mental health journal》2009,30(4):321-340
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
183.
Toon Leroy Mitchell Silva Rudi D’Hooge Jean-Marie Aerts Daniel Berckmans 《Behavior research methods》2009,41(1):148-153
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
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Mary M. Mitchell PhD Michael Shayne Gallaway PhD MA Amy M. Millikan MD MPH Michael Bell MD MPH 《Suicide & life-threatening behavior》2012,42(5):486-494
Suicide is one of the leading causes of death among U.S. Army soldiers. Suicide‐related ideation, which is associated with suicide attempts and suicide, can cause considerable distress. In a sample of 1,663 recently redeployed soldiers, we used factor analysis and structural equation modeling to test the associations between combat exposure, unit cohesion, and their interaction in predicting suicide‐related ideation. We found that combat exposure was a significant risk factor for suicide‐related ideation, while unit cohesion was a significant protective factor. The significant interaction between the two factors indicated that soldiers who experienced greater combat exposure but also had higher levels of unit cohesion had relatively lower levels of suicide‐related ideation. In addition, those who had higher levels of combat exposure and lower unit cohesion were most at risk for suicide‐related ideation. Our findings indicate the importance of unit cohesion in protecting soldiers from suicide‐related ideation and suggest a higher risk group of soldiers who should be targeted for interventions. 相似文献
186.
T A Salthouse D R Mitchell E Skovronek R L Babcock 《Journal of experimental psychology. Learning, memory, and cognition》1989,15(3):507-516
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
187.
Prospective hindsight involves generating an explanation for a future event as if it had already happened; i.e., one goes forward in time, and then looks back. In order to examine how shifts in perspective might influence people's perceptions of events, we investigated two possible factors: temporal perspective (whether an event is set in the future or past) and uncertainty (whether the event's occurrence is certain or uncertain). In the first experiment, temporal perspective showed little influence while outcome uncertainty strongly affected the nature of explanations for events. Explanations for sure events tended to be longer, to contain a higher proportion of episodic reasons, and to be expressed in past tense. Evidence from the second experiment supports the view that uncertainty mediates not the amount of time spent explaining, but rather subjects' choice of explanation type. The implications of these findings for the use of temporal perspective in decision aiding are discussed. 相似文献
188.
Sociometric measures were used to predict peer helpfulness of youth in a residential treatment center. Seventeen female adolescents with conduct disorders were asked to choose three peers in their group who were most popular, similar, well-liked, and competent. These sociometric measures were correlated with the frequency in which each peer was nominated as most and least helpful in several problem scenarios representing actual situations encountered in residential settings. A multiple linear regression analysis indicated that “popularity” was the best predictor of peer helpfulness across the problem scenarios. Discussion focused on the impact of popularity on treatment strategies for youth in residential placement. 相似文献
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190.