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21.
Because carbon monoxide (CO) is an easily understood danger of cigarette smoking, new breath CO analyzers may be useful in cessation programs. Self-reported cigarette consumption and breath CO correlated .70 using a 90-sec. CO-determination method. Smokers averaging 17 daily cigarettes had average breath CO of 24 parts per million (ppm), falling to 7.71 ppm for smokers claiming at least 24-hr. abstinence. Corresponding carboxyhemoglobin (COHb) estimates were 4.34% (slightly above World Health Organization 4% safety limit) and 1.39%. Smoking clinics can use CO-monitoring devices for feedback or surveillance, although feedback would provide the most benefits for participants. 相似文献
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Subjects searched for predesignated consonant letters embedded in strings of consonants, consonants and vowels, or consonants and numbers. In Experiments 1-3, detection was quicker in the consonant-vowel and consonant-number strings than in the consonant strings. Apparently, vowels and numbers were less confusable distractors than are nontarget consonants. Experiment 4 tested whether psychophysical or categorical information about letters and numbers enabled subjects to process consonant-vowel and consonant-number strings more quickly. Results indicated that psychophysical characteristics of target and distractor letters mediated both word and nonword superiority effects.
相似文献23.
Adaptation in the constancy of visual direction can be obtained under two radically different conditions, called eye-movement adaptation and field adaptation. Adaptation resulting from these conditions and from a “normal” condition was measured with a newly developed estimation test. Eye-movement adaptation was found to cause an alteration of compensatory eye movements. It apparently consists of a changed evaluation of eye movements, as demonstrated by two different pointing tests. A form test where the shape of a large oblong is set to look square also confirmed this interpretation. After field adaptation, a pointing test did not register a change, but an adaptation effect could be measured with a forward direction test. This test and a square test where no eye movements were permitted proved to be specific to field adaptation; they measured no effect after eye-movementadaptation. The normal adaptation condition Was apparently equivalent to the eye-movement adaptation condition. Its effect could be measured only with a pointing test. When we changed the normal adaptation condition so that frequent saccades were made during head turning, strong effects were measured with the two tests that were specific to field adaptation. 相似文献
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Two choice-reaction time studies assessed the influence of stimulus-response mapping, stimulus complexity, and stimulus alignment on adults’ discrimination of mirror-image and nonmirror-image stimulus pairs. Half the subjects in Experiment 1 were instructed to treat nonmiiTor pairs as “same” and mirror pairs as “different”; the other half responded in the opposite manner. The first group responded more quickly to nonmirror pairs, while the second group responded more quickly to mirror pairs. This result, which held for horizontal stimuli (side by side) as well as for vertical stimuli (one above the other), confirms the importance of experiential factors in mirror-image “confusions. “ In Experiment 2. stimuli were drawn from a population of patterns whose complexity could be objectively defined. In general, the more complex the pattern, the slower the response and complexity seemed to influence the qualitative nature of pattern processing. In both experiments, subjects responded more quickly to horizontal stimuli than to vertical stimuli. 相似文献
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One hundred and sixty undergraduates (80 males, 80 females) participated in a field experiment designed to examine the influence of invasions of personal space and sex of requester upon subsequent helping. On the basis of previous research, it was predicted that helping would be markedly inhibited by invasions of personal space, and that the magnitude of these effects would be mediated by the sex of the individuals who perpetrated such intrusions. Surprisingly, however, results indicated that subsequent helping was actually facilitated by such invasions. A follow-up investigation replicated these results and suggested that they stemmed from a tendency on the part of subjects to perceive close physical approach by the requester as indicative of a high need for assistance. 相似文献
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Across three studies, two experiments, and two different countries (Israel and the United States), we examine how perceptions among members of the public regarding the motives of terrorists' influence support for counterterrorist policy. We find that while perceptions that terrorists are motivated by “hatred” (rather than by a “lack of opportunity”—economic or otherwise) strongly correlate with support for harsher counter-tactics, and that these perceptions can be changed by providing information from “experts” on the “true” motivations of the outgroup, these changes in perception do not appear to cause change in support for counterterrorism policy. Our findings suggest that among the public, counterterror policy is not as instrumentally driven as much current research assumes. 相似文献