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941.
Genetic and environmental influences on childhood antisocial and aggressive behavior (ASB) during childhood were examined in 9- to 10-year-old twins, using a multi-informant approach. The sample (605 families of twins or triplets) was socioeconomically and ethnically diverse, representative of the culturally diverse urban population in Southern California. Measures of ASB included symptom counts for conduct disorder, ratings of aggression, delinquency, and psychopathic traits obtained through child self-reports, teacher, and caregiver ratings. Multivariate analysis revealed a common ASB factor across informants that was strongly heritable (heritability was .96), highlighting the importance of a broad, general measure obtained from multiple sources as a plausible construct for future investigations of specific genetic mechanisms in ASB. The best fitting multivariate model required informant-specific genetic, environmental, and rater effects for variation in observed ASB measures. The results suggest that parents, children, and teachers have only a partly "shared view" and that the additional factors that influence the "rater-specific" view of the child's antisocial behavior vary for different informants. This is the first study to demonstrate strong heritable effects on ASB in ethnically and economically diverse samples.  相似文献   
942.
This investigation examined the validity of using ratings of perceived exertion (RPE) to regulate intensity during resistance exercise. 19 male (M age = 22.2 yr., SD = 2.7) and 19 female (M age = 21.4 yr., SD = 2.3) participants estimated exertion when performing the knee extension at 40% to 90% of one-repetition maximum. One week later, participants were asked to produce weights for the knee extension that elicited the feelings of exertion associated with 9, 13, and 17 on the Borg RPE scale. The weight produced at 9, 13, and 17 during the production session was compared to the weight lifted at each RPE during the estimation session. The effect sizes associated with the differences in weight lifted across sessions at each RPE were generally small in magnitude, especially at the higher intensities (ES = .40, -.09, .15, respectively). The results of this investigation support the use of RPE as a method of prescribing the intensity of resistance exercise.  相似文献   
943.
Some researchers argue that task switching involves task-set reconfiguration-that is, changing the existing task set to perform a different task. Although this idea is intriguing, it is often unclear what is reconfigured and which processes are involved in reconfiguration. We addressed these issues by defining task sets, identifying differences between them, and obtaining evidence that was diagnostic of reconfiguration. In two experiments, subjects performed relative judgment tasks that involved comparing a target with a reference point that repeated or switched across trials. The task was the same on every trial, but the task set was not, because a task-set parameter-the reference point-had to be changed. Target-reference point distance effects that changed with the reference point provided diagnostic evidence that reconfiguration occurred, and this reconfiguration led to switch costs. We discuss how our approach can be generalized to define reconfiguration more clearly in other task-switching situations. nt|mis|This research was supported by Grants BCS 0133202 and BCS 0446806 from the National Science Foundation to G.D.L.  相似文献   
944.
In this study, the authors investigated the characteristics that predict best friend status in young children. One hundred and twenty-four preschool, kindergarten, and first-grade children identified their "best friend" and up to four "other friends" in their class. Teachers completed a questionnaire about each friendship to determine positive and negative features of the relationships. First, the authors used individual characteristics to predict if a child had a best friend. The variables age, gender, and peer acceptance predicted that a child would have a best friend. Second, positive friendship features positively predicted best friendships in analyses of all friendship pairs. Best friendships are meaningful relationships to children even at this young age and offer children more positive experiences than do other friendships.  相似文献   
945.
Countless studies have recently purported to demonstrate effects of goal priming; however, it is difficult to muster unambiguous support for the claims of these studies because of the lack of clear criteria for determining whether goals, as opposed to alternative varieties of mental representations, have indeed been activated. Therefore, the authors offer theoretical guidelines that may help distinguish between semantic, procedural, and goal priming. Seven principles that are hallmarks of self-regulatory processes are proposed: Goal-priming effects (a) involve value, (b) involve postattainment decrements in motivation, (c) involve gradients as a function of distance to the goal, (d) are proportional to the product of expectancy and value, (e) involve inhibition of conflicting goals, (f) involve self-control, and (g) are moderated by equifinality and multifinality. How these principles might help distinguish between automatic activation of goals and priming effects that do not involve goals is discussed.  相似文献   
946.
We aimed to expand upon the demographic characteristics and gender differences among those who have met someone on the Internet who they later met offline and had sex with as well as any relationship with cybersex, sexually transmitted infections, and online sexual problems. We analyzed data collected through an online questionnaire in 2002 in Sweden including a total population of 1836 respondents of which 1458 used the Internet for sexual purposes. Of those, 35% men and 40% women reported to have met offline sex partners online. The majority reported an occurrence of one to two times, whereas 10% reported six or more times. The analysis suggested women aged 34-49 and 50-65 years, homo- and bisexual men, and singles more likely to have this experience. They were also more likely to have engaged in cybersex. No relationships were found with sexually transmitted infections or online sexual problems. The results suggest that using the Internet to find sex partners may be less hazardous for the general Internet users than pointed out by prior research about this behavior often focusing on specific sub groups of Internet users.  相似文献   
947.
Participants were asked to recall the names when shown photographs of faces in both a semantic task (Experiment 1) and an episodic task (Experiments 2 and 3). When recall failed, feeling of knowing (FOK) ratings were solicited. In addition, participants reported on the strategies that they used to make their ratings, whether they could recall other pieces of information (the target-accessibility strategy, e.g., Koriat, A. (1993). How do we know that? The accessibility model of the feeling of knowing. Psychological Review, 100, 609–639) or whether the faces simply looked familiar (the cue-familiarity strategy, e.g., Schwartz, B. L., & Metcalfe, J. (1992). Cue familiarity but not target accessibility enhances feeling of knowing ratings. Journal of Experimental Psychology: Learning, Memory, and Cognition, 18, 1074–1083). In all experiments, FOK ratings were fairly accurate in that participants were successful in predicting their performance on a subsequent recognition test. More importantly, participants reported using the cue-familiarity strategy more often, although they gave higher FOK ratings when they reported using the target-accessibility strategy. The FOK ratings that were given using the two strategies were equally accurate.  相似文献   
948.
It is often assumed that indeterminacy in mereological relations—in particular, indeterminacy in which collections of objects have fusions—leads immediately to indeterminacy in what objects there are in the world. This assumption is generally taken as a reason for rejecting mereological vagueness. The purpose of this paper is to examine the link between mereological vagueness and existential vagueness. I hope to show that the connection between the two forms of vagueness is not nearly so clear-cut as has been supposed.  相似文献   
949.
The purpose of this study was to investigate how brief experimental analyses (BEAs) could be used to identify effective interventions for Kindergartners (2 girls and 2 boys, 5 years and 7-10 months old) with low performance and/or growth slope in letter sound fluency (LSF). Interventions were tested within a multielement design with brief mini-reversals until an intervention yielding at least 20% improvement on a specific subskill measure or a curriculum-based measure of LSF was identified. BEA-identified interventions were implemented one-on-one for 5 to 9 weeks. A multiple-baseline design across participants showed large intervention effects (average adjusted d = 2.4) on general outcome measures, supporting treatment validity of BEAs. Findings extend the BEA literature to younger participants, early reading interventions, and early reading measures.  相似文献   
950.
Maria Caama?o 《Erkenntnis》2009,70(3):331-364
The incommensurability thesis, as introduced by T.S. Kuhn and P.K. Feyerabend, states that incommensurable theories are conceptually incompatible theories which share a common domain of application. Such claim has often been regarded as incoherent, since it has been understood that the determination of a common domain of application at least requires a certain degree of conceptual compatibility between the theories. The purpose of this work is to contribute to the defense of the notion of local or gradual incommensurability, as proposed by late Kuhn. The application of this notion would allow to render the incommensurability thesis coherent. To support this view, a typical example of incommensurability will be formally analyzed by applying the structuralist metatheory developed, among others by W. Balzer, C.U. Moulines and J.D. Sneed. The structural reconstruction of the relation between the phlogiston theory and the oxygen theory offered here will reveal that they are locally incommensurable, and will even make possible to determine the ontological reduction relation that they also exemplify.
Maria Caama?oEmail:
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