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In the discussion of the responsibilities of society to the HIV infected and uninfected, a serious question seems to have been left out of the picture: To what extent are people who are not infected, have no special relationship to the infected and have no professional responsibilities for the care of AIDS patients under an obligation to come to the aid of people with the HIV? In this paper, I shall examine our responsibilities, as members of society, for the welfare of others to whom we may or may not have a special relationship. I shall argue that those responsibilities flow from the conditions that structure our transactions with others; conditions that make such transactions possible.  相似文献   
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In this paper, we describe software that turns a Macintosh computer into an off-the-shelf tool for experiments on visual search. Our design goals included portability (between members of the Macintosh computer family and between various research settings), user-friendliness (equivalent to Macintosh programming standards), flexibility (to allow replication and extension of important experiments on visual search), and adaptability (very short design-to-data and data-to-analysis turnaround times). We describe how the software meets these goals in three major phases of an experiment: stimulus construction, experimental control, and statistical analysis. We then list several landmark studies of visual search that can be easily designed and extended with the software. Finally, we outline plans for expanding the experimental variations that will be supported in future versions of the software.  相似文献   
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An automated system for measuring intracranial self-stimulation behavior is described. The system consists of two Commodore 6502 microcomputers interfaced with a constant-current generator and a standard operant chamber. The system hardware allows sine- and square-wave stimulation. Stimulus intensity can be varied in 256 steps between 0 and 100, 0 and 500, or 0 and 1,000 /µA. The system programs, which are written in machine language, allow the control of various schedules of reinforcement, the counting of operant responses and reinforcements, the measurement of interresponse intervals, and the storage of the data on disk. The software is designed for the determination of the threshold of reinforcement, on the basis of the titration of postreinforcement pauses caused by changeover in schedule control between concurrent continuous reinforcement and fixed ratio schedules.  相似文献   
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Growth systematically changes the body proportions of both humans and animals so that the ratio of head height to body height decreases with age. Prior studies have demonstrated that body proportions provide effective information for age perception. To test the proposal that illustrators incorporate this information into their drawings, measurements were made of the head and body heights of 100 pairs of animals appearing in children’s picture books. In 93 pairs, the animal intended to be perceived as older had a smaller head-to-body ratio than did the younger animal. Ratings collected for 25 of these pairs showed that both perceived age and cuteness are significantly correlated with body proportions. The magnitudes of the correlations were only modest, suggesting that other aspects of the drawings influenced perceived age and cuteness. In addition, observers reported that body proportions are only one of a variety of factors influencing age and cuteness perception. As has been found in other studies, perceived age and cuteness were negatively correlated.  相似文献   
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OPTIMISM AND FUNDAMENTALISM   总被引:2,自引:0,他引:2  
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