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931.
The present study, based upon the national 2005 Youth Risk Behavior Survey of U.S. high school students, provides the most current and representative data on dating violence among adolescent females (N = 7,179). The dependent variable was physical dating violence. The independent variables included four dimensions: violence, suicide, substance use, and sexual risk behavior. Unadjusted odds ratios (OR) and 95% confidence intervals (CI), were examined followed by multivariate logistic regression analyses, which included all significant independent variables from the bivariate analyses. Adjusted OR and 95% CI were computed to assess the significance of the relationships. In terms of prevalence, 10.3% of female adolescents reported experiencing physical dating violence. Black girls (OR = 1.47) and girls who reported sad/hopeless feelings (OR = 1.42) considered suicide (OR = 1.55), engaged in physical fighting (OR = 2.17), had recent sexual partners (OR = 2.10), or had unprotected sexual intercourse (OR = 1.70) were more likely to report physical dating violence. These findings suggest dating violence against adolescent females is widespread and associated with a host of other risk factors that deserve further attention through longitudinal research and intervention efforts. 相似文献
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Rachlin H 《Journal of the experimental analysis of behavior》2007,87(1):143-149
The three requirements for a Darwinian evolutionary process are replication, variation and selection. Dennett (2006) discusses various theories of how these three processes, especially selection, may have operated in the evolution of religion. He believes that the origins of religion, like the origins of language and music, may be approached scientifically. He hopes that such investigations will open a dialog between science and religion leading to moderation of current religious extremism. One problem with Dennett's program, illustrating the difficulty of breaking away from creationist thinking, is Dennett's own failure to consider how Darwinian methods may be used to study evolution of behavioral patterns over the lifetime of individual organisms. 相似文献
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Trachtman H 《The American journal of bioethics : AJOB》2007,7(11):27-8; discussion W1-2
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A computational model for the perception of counterchange-specified motion is examined in detail and compared with various versions of the Reichardt motion detection model [Reichardt, W. (1961). Autocorrelation, a principle for the evaluation of sensory information by the central nervous system. In W. A. Rosenblith (Ed.), Sensory communication (pp. 303-317). New York: Wiley]. The counterchange model is composed of a pair of temporally biphasic subunits at two retinal locations, one detecting decreases and the other increases in input activation. Motion is signaled when both subunits are simultaneously excited, as determined by the multiplicative combination of their transient responses. In contrast with the Reichardt detector, which effectively tracks motion energy and accounts solely for results obtained with standard apparent motion stimuli (a surface is visible at one location, then at another), the counterchange model also accounts for the generalized apparent motion perceived between pairs of simultaneously visible surfaces. This indicates that standard apparent motion can be perceived via the same non-sequential, non-motion-energy mechanism as generalized apparent motion. There is no need for either an explicit delay mechanism to account for optimal motion perception at non-zero inter-stimulus intervals, or for inhibitory interaction between subunits to account for the absence of motion in the detector’s null direction (Barlow, H. B., & Levick, W. R., 1965). Both are emergent properties that result from the inhibitory states of the counterchange detector’s biphasic subunits. In addition to apparent motion, the counterchange principle potentially accounts for the perception of motion for drifting gratings, the short range motion perceived for random-dot cinematograms, and the motion perceived for continuously moving objects. 相似文献
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Kimberly A.S. Howard Lea Ferrari V. Scott H. Solberg 《Journal of Vocational Behavior》2009,75(2):100-108
This study examined the role of supportive relationships (i.e., family, teacher, and peer) and agency (i.e., self-efficacy, motivation, and goal-setting orientation) on three outcomes: academic grades, distress, and career decidedness. Data from 588 middle school youth from Northern (N = 322) and Southern (N = 266) Italy were analyzed using path modeling. Results indicated that across gender and region, agency was consistently related to academic grades and career decidedness. However, the role of supportive relationships was found to differ across gender and region. For both boys from Northern Italy and girls from Southern Italy, the impact of family support on academic grades and career decidedness was mediated by agency. For girls from Northern Italy, family support related directly to academic grades and career decidedness. Implications for practice were described. 相似文献