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81.
Tarja Heponiemi Marko Elovainio Laura Pulkki Sampsa Puttonen Olli Raitakari Liisa Keltikangas-J?rvinen 《Health psychology》2007,26(1):13-21
The present study examined the association of cardiac autonomic task-induced reactivity and recovery to preclinical atherosclerosis. Thirty-three men and 33 women aged 24-39 years participated in the ongoing epidemiological Cardiovascular Risk in Young Finns study. The authors measured heart rate (HR), respiratory sinus arrhythmia (RSA), and preejection period (PEP) during the mental arithmetic and speech tasks in 1999. Carotid atherosclerosis was assessed by measuring the thickness of the common carotid artery intima-media complex (IMT) with ultrasound in 2001. Higher HR, RSA, and PEP reactivity were associated with lower IMT values even after adjusting for cardiovascular risk factors (lipid levels, obesity, and blood pressure). In addition, better HR recovery after the mental arithmetic task was associated with lower IMT values, and this association persisted after all adjustments. Thus, higher task-induced cardiac autonomic reactivity and better HR recovery were related to less preclinical atherosclerosis. The authors concluded that cardiac pattern of reactivity and quick recovery may be associated with better cardiovascular health, and therefore all reactivity occurring in challenging situations should not automatically be considered as potentially pathological. 相似文献
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Philosophical Studies - A prominent way of explaining how race is socially constructed appeals to social positions and social structures. On this view, the construction of a person’s race is... 相似文献
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Two experiments examined effects of repetition and change on states of awareness in face recognition. Participants studied repeatedly presented photographs of faces, with the second presentation following either immediately after the first presentation (massed repetition) or following six intervening items (spaced repetition). To manipulate perceptual change, each repeated face was either identical or a mirror image of the first presentation. Subsequently, when recognising a face, participants indicated whether they consciously recollected its prior occurrence ("remembering") or recognised it on the basis of familiarity ("knowing"). Changes in appearance between repeated faces enhanced remember, but not know, responses, and these effects were accentuated for spaced, rather than massed, repetition. These findings suggest that distinctiveness of encoding supports the phenomenological experience of conscious remembering. 相似文献
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Rosenthal SL Griffith JO Succop PA Biro FM Lewis LM DeVellis RF Stanberry LR 《Adolescence》2002,37(145):83-92
This longitudinal study examined adolescent girls' perception of control over sexually transmitted disease (STD) acquisition. Participants were asked questions regarding their perception of their STD locus of control (internal control; control by parents, partners, peers, and health care providers; and chance) at two waves of data collection. Of the 116 participants (mean age = 17 years), 82% were African-American and 18% were Caucasian. Responses to the measure of locus of control were significantly correlated across a 6-month interval. The responses regarding internal control, control by partner, and chance were not related to the acquisition of an STD in the next 6 months. Further, they were not influenced by an STD in the preceding 6 months. These results indicate that responses to a locus of control measure were stable over a 6-month period, and internal, partner, and chance locus of control perceptions seem to be neither determined by STD experience nor directly related to future STD acquisition. However, understanding an individual's locus of control may be helpful in providing appropriate counseling. Future research could examine how adolescent girls form their perceptions of control over STD acquisition. 相似文献
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Data in social and behavioral sciences are often hierarchically organized though seldom normal, yet normal theory based inference procedures are routinely used for analyzing multilevel models. Based on this observation, simple adjustments to normal theory based results are proposed to minimize the consequences of violating normality assumptions. For characterizing the distribution of parameter estimates, sandwich-type covariance matrices are derived. Standard errors based on these covariance matrices remain consistent under distributional violations. Implications of various covariance estimators are also discussed. For evaluating the quality of a multilevel model, a rescaled statistic is given for both the hierarchical linear model and the hierarchical structural equation model. The rescaled statistic, improving the likelihood ratio statistic by estimating one extra parameter, approaches the same mean as its reference distribution. A simulation study with a 2-level factor model implies that the rescaled statistic is preferable.This research was supported by grants DA01070 and DA00017 from the National Institute on Drug Abuse and a University of North Texas faculty research grant. We would like to thank the Associate Editor and two reviewers for suggestions that helped to improve the paper. 相似文献