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31.
Visual control of step length during running over irregular terrain   总被引:1,自引:0,他引:1  
Running over uneven ground requires visually regulating step length to secure proper footing. To examine how this is achieved, we studied subjects running on a treadmill on a series of irregularly spaced targets. The movements of their lower limbs and coccyx relative to the targets were monitored opto-electronically by a Selspot system. The results indicated that step length was adjusted to strike the targets primarily by varying the vertical component of impulse applied to the ground during the stance phase. In contrast, horizontal impulse was not varied significantly, and changing the reach forward of the foot on landing contributed little to variation in step length. Changing the vertical impulse simply altered the step time proportionately. Thus the data are consistent with a time-based model in which vertical impulse is modulated by the optic variable delta tau (Lee, 1976) specifying the time gap that has to be bridged by the runner between two targets.  相似文献   
32.
Though the term “new technology” is widely used and discussed, there has been very little systematic study of attitudes to technology and their relation to other beliefs and group memberships. This article describes an initial investigation into the nature of attitudes towards new technology (n=534 undergraduates) and demonstrates that, as yet, these attitudes are only weakly structured and are not fully integrated with other social beliefs. General evaluations of the benefits of technological advance appear to be almost unrelated to beliefs about the inevitability of these advances or the desire to acquire training to deal with them. Contrary to popular expectations, evaluations of video games are unrelated to other beliefs about technology while other social beliefs are, as yet, only weakly integrated with these attitudes. This study also identifies gender differences in the assessment of potential benefits and highlights other differences attributable to academic group memberships. These finding are discussed with reference to the literature on sex-role stereotyping and group socialization processes.  相似文献   
33.
This study examined whether norms that concerning assisting frail older parents were different for daughters than for sons when the adult children are members of dual-earner couples. Data were gathered by telephone interviews from a probability sample of 315 adults residing in western Alabama. Of the 18 statements presented, statistically significant differences between the expectations for daughters and sons occurred in only three cases (help with housework, meal preparation, and yard work), suggesting substantial support for norms of equalitarianism. Further, there were few differences between the expectations held by females and by males for daughters and sons. Generally, the results suggested strong support for behaviors that facilitate the independent living of both adult children and their frail older parents.The authors acknowledge with thanks the assistance of the University of Alabama's Capstone Poll, which collected the data for this study.  相似文献   
34.
This study examines whether and how the association between religious homogamy (i.e., whether spouses have the same religious affiliation) and marital satisfaction varies across religious affiliations by utilizing a unique context that four large religious groups (i.e., Buddhists, Protestants, Catholics, and religious nones) coexist in South Korea. Our results show that while religious homogamy has a positive relationship with marital satisfaction among Protestants and Catholics, there is no such association among Buddhists. This study also reveals that higher levels of religious attendance intensify the positive relationship between religious homogamy and marital satisfaction only among Protestants. Moreover, religious heterogamy is positively associated with marital relationships among religious nones compared to religious homogamy. However, this pattern held only for religious nones who married Buddhists or Catholics. We discuss the implications of our findings for research on religion and marriage from cross-cultural perspectives.  相似文献   
35.
Chanwoo Lee 《Ratio》2023,36(3):192-203
The apparent chasm between two camps in metaphysics, analytic metaphysics and scientific metaphysics, is well recognized. I argue that the relationship between them is not necessarily a rivalry; a division of labour that resembles the relationship between pure mathematics and science is possible. As a case study, I look into the metaphysical underdetermination argument for ontic structural realism, a well-known position in scientific metaphysics, together with an argument for the position in analytic metaphysics known as ontological nihilism. I argue that we can ascribe the same schema to both arguments, which indicates that analytic metaphysics can offer an abstract model that scientific metaphysics may find useful.  相似文献   
36.
Asian Americans are lauded as the model minority who are intelligent and industrious. Simultaneously, they are deemed as perpetual foreigners. The current research examines how racial microaggressions expressed by a White American source toward an Asian American target affect perceptions of the perpetrator and target. White Americans and Asian Americans read about an interaction between two college students, where the racial microaggression made was either an ambiguous expression of the model minority myth (MMM; all studies), an ambiguous perpetual foreigner stereotype (all studies), an unambiguous MMM (all studies), or no racial bias (Studies 2 and 3). Findings indicate that both Whites and Asian Americans respond differently—when exposed to the aforementioned conditions—regarding perceived racism of the White perpetrator and appropriateness of response by the Asian American target; however, they respond similarly regarding perceived legitimacy of collective action by the target. Nevertheless, Whites and Asian Americans deemed the ambiguous microaggression against the target as a model minority not racist relative to unambiguous MMM. Our findings show that ambiguous forms of bias toward Asian Americans go “under the radar” of both Whites and Asian Americans as being racist and contribute to the maintenance of the racial status quo.  相似文献   
37.
Animal Cognition - Exploring new and unfamiliar environments is critical for survival, providing information on food, shelter, mates, and sources of danger. The open field paradigm is commonly used...  相似文献   
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39.
The plastic barrel suit provides complete protection of chronically implanted fistulas and electrical connectors. The lost time, expense, and the frustrations of having these devices damaged was avoided.  相似文献   
40.
Wayne Lee 《Psychometrika》1966,31(3):397-412
A method of design symbolization (DS) is given for a class of designs in which all factors are related by complete crossing or by nesting. Characterization of acceptable DS's, and logical relational properties are given. It is shown how the design model can be obtained from the DS.The preparation of this article was supported by NIH Grant GM-11128, and by grants to the Institute of Human Learning by NSF and NIH.  相似文献   
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