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A subsample of 814 sexually experienced adolescent females from the 1979 U.S. National Survey of Young Women was analyzed to assess the correlates of age at 1st sexual intercourse. Multiple regression procedures were used to examine sets of variables sequentially. In the hierarchical regression model, the control variables (respondent's age, race, religion, and age at menarche), along with 3 independent variables (household income, ideal age at 1st marriage, and ideal age for 1st birth), predicted age at 1st intercourse. The control variables accounted for a major portion of the variance in the model. Of the controls, chronological age and age at menarche were highly significant across all models tested.  相似文献   
85.
Tachistoscopic presentation of stimuli on IBM PC-compatible computers is limited by a number of factors, including video retrace rates, screen scrolling, and the shape and density of picture elements. A method is presented for overcoming these difficulties through the use of enhanced graphic adapters or video graphic arrays. A C-language program demonstrates (1) synchronous scroll-free displays achieved by writing alternating images to “hidden” pages of video memory, (2) alternative techniques for erasing images, and (3) use of an empirically derived aspect ratio to produce symmetrical figures.  相似文献   
86.
The debate regarding the unitary versus multiple nature of the human person is examined with special attention to the division between conscious and unconscious. The roots of the unconscious are traced to the experience of alienation or feeling divided within. An existential analysis is provided in order to shed light on the nature of the unconscious. The experience of feeling divided within is explained as a metaphor that is taken literally. An existential-phenomenological explanation of the unconscious is provided which preserves the essential unity of the human person.  相似文献   
87.
Child-to-parent transmission of cytomegalovirus may be reduced by increasing protective behaviors (handwashing and glove use) and decreasing risky behaviors (intimate contact between child and parent). This study showed that an educational intervention resulted in increases in reported and objective measures of protective behaviors and decreases in reported risky behaviors. Further study must determine if changes in protective and risky behavior are maintained and prevent cytomegalovirus transmission.  相似文献   
88.
The contents of 800 singles ads were examined. They were compared by the gender of the advertiser, the year of appearance (1991 and 1986), and the SES of the target readership (affluent and general). There were very few advertisers who listed themselves as black, so these ads were not included in the study. Gender differences were most important. Men were more likely to offer financial security and seek attractiveness. Women were more likely to offer attractiveness and seek financial security. The gender differences were in agreement with those reported for over a decade and from many geographical areas, although less than half of the advertisers mentioned either finances or attractiveness. Contrary to our hypotheses, the contents of mens' and womens' ads were more different in 1991 than they had been in 1986 and more in conformity with sexual stereotypes. Ads in a paper with an affluent readership were more likely to mention educational and financial status while ads in a paper with a readership throughout the metropolitan area were more likely to mention physical characteristics.  相似文献   
89.
This study investigated the effectiveness of using visual cues to highlight the seams of baseballs to improve the hitting of curveballs. Five undergraduate varsity baseball team candidates served as subjects. Behavior change was assessed through an alternating treatments design involving unmarked balls and two treatment conditions that included baseballs with 1/4-in. and 1/8-in. orange stripes marking the seams of the baseballs. Results indicated that subjects hit a greater percentage of marked than unmarked balls. These results suggest that the addition of visual cues may be a significant and beneficial technique to enhance hitting performance. Further research is suggested regarding the training procedures, effect of feedback, rate of fading cues, generalization to live pitching, and generalization to other types of pitches.  相似文献   
90.
The stigma associated with obesity is likely to limit the opportunities obese women have to develop social skills. This hypothesis was tested by having obese (n = 15) and nonobese (n = 22) women converse on the telephone with college students who were unaware of the women's weights. Ratings made by judges who listened to the women's contributions to the conversations but who were unaware of their weights showed that obesity was negatively related to judgments about the women's likability, social skills, and physical attractiveness. The telephone partners of obese women rated the women and themselves more negatively than did the partners of nonobese women. Obese and nonobese women generally did not differ in their evaluations of their own and their telephone partners' behavior, and they also did not differ on a measure of social self-esteem. These findings suggest that there are real differences in the social behavior of obese and nonobese women and that these differences affect the impressions formed by those with whom they interact.  相似文献   
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