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This article examines the spatial relationships between avatars (i.e., graphical identities or icons) over time in a 2-dimensional online chat environment. The Spatial Distance Analysis Program (SDAP) was developed to measure the distance between avatars in a specially designed Palace environment. Correlations between distance and interpersonal communication constructs of (1) conversational appropriateness, (2) social attraction, and (3) uncertainty reduction indicate that distance effects are significant in an online environment. Specifically, it was found that general conversational appropriateness mediated between uncertainty reduction and specific conversational appropriateness for individuals who moved closer together and farther apart over time, respectively. Furthermore, the relationship between social attraction and distance indicated a significant positive parabolic function; that social attraction (i.e., liking) decreased at middle distances and increased at low and high distances. This finding suggests that there are three interpersonal distance zones in online communication.  相似文献   
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Obese persons with hypertension are at greater risk for diabetes and hyperlipidemia than normotensive obese persons. It has been postulated that increased lipolytic rates contribute to these metabolic diseases. Therefore, we evaluated the glycerol rate of appearance (Ra) in plasma, an index of whole-body lipolytic activity, during basal conditions and during 60 minutes of epinephrine infusion after 12 and 84 hours of fasting in six normotensive (body mass index [BMI], 39.9 +/- 1.8 kg/m2) and six hypertensive (BMI, 38.7 +/- 1.6 kg/m2) obese persons. Basal glycerol Ra was lower in hypertensive than in normotensive subjects at both 12 hours (1.58 +/- 0.21 v 2.27 +/- 0.28 mumol/kg/min, respectively; P < .01) and 84 hours (2.04 +/- 0.06 v 2.50 +/- 0.13 mumol/kg/min, respectively; P < .01) of fasting. Peak glycerol Ra during epinephrine infusion after 84 hours of fasting (5.69 +/- 0.72 and 11.40 +/- 0.78 mumol/kg/min for hypertensive and normotensive subjects, respectively) was significantly greater than at 12 hours (3.09 +/- 0.29 and 5.06 +/- 0.69 mumol/kg/min) in both hypertensive and normotensive subjects. However, peak glycerol Ra was lower in hypertensive than in normotensive subjects after 12 and 84 hours of fasting (P < .01 for 84 hours). We conclude that hypertension in obese persons is associated with a decrease in both basal lipolytic rates and lipolytic sensitivity to epinephrine infusion.  相似文献   
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We investigated the utility of two approaches for exploiting pleiotropy to search for genes influencing related traits. To do this we first assessed the genetic correlations among a set of five closely related quantitative traits (Q1, Q2, Q3, Q4, Q5). We then used the genetic correlations among these five traits both to remove the common genetic effects of the four remaining traits, thereby identifying the unique genetic contribution to each trait, and to extract a synthetic phenotype which exploits the shared genetic information (pleiotropy) among these five traits. After obtaining these conditional traits, we then searched for evidence of quantitative trait loci (QTLs) (using variance component linkage) influencing the unique residual genetic component for each trait as well as those influencing the expression of the synthetic traits. From this work, we conclude that the removal of the common genetic effects of other traits in a group may be of greater utility when the majority of the pleiotropy initially detected between traits is attributable to the shared additive effects of polygenes, rather than to those of major loci. By contrast, decomposition of the genetic covariance matrix to its principal components is a greater utility when the majority of pleiotropy is attributable to major loci.  相似文献   
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