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101.
Heterogeneity in the longitudinal course of depressive symptoms was studied through the use of general growth mixture modeling for young men in the Oregon Youth Study (N=206), who ranged in age from 15 to 24 years. Four trajectory classes were identified: the very-low, the moderate-decreasing, the high-decreasing, and the high-persistent classes. The 3 lowest classes differed primarily quantitatively with the initial level or mean level across time being the major determinant of class differences, whereas the high-persistent class appeared qualitatively different in terms of long-term developmental trends and variation. Findings from univariate and multivariate analyses revealed specific effects of childhood, parental, contextual, and individual risk factors on the class membership as well as on the growth within each trajectory class.  相似文献   
102.
The authors investigated the factor structure and construct validity of the Fraboni Scale of Ageism and the age and gender differences in ageism scores. Confirmatory factor analyses supported the multidimensional nature of FSA scores and generally corroborated the initial factor structure reported by M. Fraboni, with some notable exceptions. Essentially, the present findings were aligned with theoretical models of ageism that emphasize both cognitive facets and affective facets. That is, on the basis of their factor analytic findings, the authors redefined Fraboni's original factors of Antilocution, Avoidance, and Discrimination as Stereotypes, Separation, and Affective Attitudes, respectively, because of the clustering of items within factors. The revised 3-factor structure accounted for 36.4% of the variance in FSA scores. FSA factor scores significantly related to other scores from other measures of age-related attitudes, with higher correlations among factors that were similar in terms of their cognitive nature versus their affective nature. Finally, younger individuals and men had significantly higher ageism scores on the FSA than older individuals and women. The authors discussed the importance of adequately assessing ageism, with particular emphasis devoted to the understanding of age bias.  相似文献   
103.
In order to determine the reflectance of a surface, it is necessary to discount luminance changes produced by illumination variation, a process that requires the visual system to respond differently to luminance changes that are due to illumination and reflectance. It is known that various cues can be used in this process. By measuring the strength of lightness illusions, we find evidence that straightness is, used as a cue: When a boundary is straight rather than curved, it has a greater tendency to be discounted, as if it were an illumination edge. The strongest illusions occur when a boundary has high contrast and has multiple X-junctions that preserve a consistent contrast ratio.  相似文献   
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The relative effectiveness of explicit instruction, guided discovery, and discovery learning techniques in enhancing anticipation skill in young, intermediate-level tennis players was examined. Performance was assessed pre- and postintervention, during acquisition, and under transfer conditions designed to elicit anxiety through the use of laboratory and on-court measures. The 3 intervention groups improved from pre- to posttest compared with a control group (n = 8), highlighting the benefits of perceptual-cognitive training. Participants in the explicit (n = 8) and guided discovery (n = 10) groups improved their performance during acquisition at a faster rate than did the discovery learning (n = 7) group. However, the explicit group showed a significant decrement in performance when tested under anxiety provoking conditions compared with the guided discovery and discovery learning groups. Although training facilitated anticipation skill, irrespective of the type of instruction used in this experiment, guided discovery methods are recommended for expediency in learning and resilience under pressure.  相似文献   
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A confirmatory model integrating Japanese ethnicity, cultural identity, and depression was developed (N = 140). The model incorporated the Center for Epidemiologic Studies-Depression Scale (CES-D), Major Life Events Scale, and Japanese Cultural Scale. Japanese American adolescents scored higher on the Japanese Cultural Scale and reported fewer depressive symptoms on the CES-D total and on 2 of the 3 CES-D factors than part-Japanese American adolescents. Predictors for depression were being Japanese American vs. part-Japanese American, female gender, and culturally intensified events. A significant interaction of behavior by self-identification was noted. The model had good overall fit and suggested that the formation of cultural identity may contribute to depressive symptoms experienced by adolescents, particularly adolescents of mixed heritage.  相似文献   
107.
Bottlenose dolphins are unusual among non-human mammals in their ability to learn new sounds. This study investigates the importance of vocal learning in the development of dolphin signature whistles and the influence of social interactions on that process. We used focal animal behavioral follows to observe six calves in Sarasota Bay, Fla., recording their social associations during their first summer, and their signature whistles during their second. The signature whistles of five calves were determined. Using dynamic time warping (DTW) of frequency contours, the calves signature whistles were compared to the signature whistles of several sets of dolphins: their own associates, the other calves associates, Tampa Bay dolphins, and captive dolphins. Whistles were considered similar if their DTW similarity score was greater than those of 95% of the whistle comparisons. Association was defined primarily in terms of time within 50 m of the mother/calf pair. On average, there were six dolphins with signature whistles similar to the signature whistles of each of the calves. These were significantly more likely to be Sarasota Bay resident dolphins than non-Sarasota dolphins, and (though not significantly) more likely to be dolphins that were within 50 m of the mother and calf less than 5% of the time. These results suggest that calves may model their signature whistles on the signature whistles of members of their community, possibly community members with whom they associate only rarely.  相似文献   
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