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Visual acuity for the detection of gratings at four orientations was measured for groups of ten boys and ten girls aged five to seven years, from the following four populations: Scots in Glasgow, Pakistanis in Glasgow, Gaels in Stornoway (Outer Hebrides) and East Anglians in Littleport (Cambridgeshire fenlands). The Glaswegians, both Scottish and Pakistani, showed the normal pattern of anisotropy, with poorest acuity for oblique orientations; the East Anglians showed no significant anisotropy; while the Gaels were unusual in showing poorest horizontal acuity. A group of fourteen Pakistani children in Stornoway differed slightly from a matched group of Gaels. The group differences bore little relation to the visual environments, and were probably due to genetic or cultural factors. The relatively poor horizontal acuity of the Gaels was not correlated with astigmatism. Sex differences were also found, with the boys showing higher mean acuity and a higher ratio between vertical and oblique acuity. 相似文献
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Cardiovascular reactivity to video game and mental arithmetic stressors was compared among three groups of men: aerobically trained mild hypertensives, untrained mild hypertensives, and a comparison group of untrained normotensives. Relative to the untrained hypertensives, the trained hypertensives reacted to the video game with marginally smaller systolic blood pressure and diastolic blood pressure, but there were no significant differences between these groups in reactivity during the mental arithmetic task. Comparisons between each hypertensive group and the normotensive group showed that blood pressure (BP) reactivity of normotensives during the video game was generally similar to that of trained hypertensives but smaller than that of untrained hypertensives. These results indicate that aerobic training, which has been found to reduce resting BP in mild hypertensives, may also exert a favorable impact in reducing cardiovascular reactivity of hypertensives during some stressful situations. 相似文献
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Although message‐production theories often assume that goals behave dynamically to direct communication behavior, few studies consider the interconnectedness of goals and behavior throughout interactions. Here, the interrelationship of communication goals and tactics was examined through a sequential analysis of 47 conflict interactions between close friends or dating partners. It was posited that for both the initiators and resistors in a conflict, the importance of relational or other‐identity goals would be associated with the use of integrative tactics and the importance of instrumental or self‐identity goals would be related to the use of distributive tactics. We examined these predictions within and across partners. Analyses indicated that for both conflict initiators and resistors, the importance of a combination self/instrumental goal predicted the use of distributive tactics and the importance of an other‐identity goal lead to partner‐oriented tactics. For resistors, the importance of an instrumental goal was associated with the use of distributive tactics and the importance of a combination identity/relational goal was aligned with issue‐oriented tactics as well. Across partners, several significant patterns between one partner’s use of distributive or integrative tactics and the other partner’s goals were observed. Implications of the results for understanding conflict and message production are discussed. 相似文献