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The acquired immune deficiency syndrome (AIDS) has rapidly become the most serious medical consequence of injecting illicit drugs. Its potential impact on intravenous (IV) drug use is enormous. Human immunodeficiency virus (HIV, also known as HTLV-III and LAV), the virus that causes AIDS, appears, usually, to lead to lifelong infection. At present there is no effective treatment, and the treatments under development may require lifelong antiviral therapy. Since most of the antibody produced in response to HIV infection does not neutralize the virus, and since there is substantial genetic variation in the virus, it will be difficult to develop a vaccine. Even after vaccines are developed, testing their safety and efficacy will be formidable problems. Until either effective treatment or vaccines are developed, control of the epidemic among IV drug users must be attempted through behavior change/prevention efforts. In this paper we will review the epidemiology of AIDS among IV drug users and characteristics of the IV drug-use subculture relevant to prevention efforts. We will then identify different target groups for these prevention efforts, present available evidence about behavior change in these groups, and then briefly discuss how to prevent transmission of HIV to heterosexual partners who are not themselves IV drug users and to the children of IV drug users. 相似文献
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Research has shown that many individuals do not routinely evaluate new information for consistency with respect to what they already know. One factor that may affect the likelihood of critical evaluation is whether or not the information is the central focus of the message. Two experiments tested this possibility by establishing differential emphasis of false information within complex sentences. Half of the target sentences contained a false fact in the main clause and half contained a false fact in the subordinate clause. In Experiment 1 subjects verified 64 sentences presented orally as either true or false. In Experiment 2 subjects read and evaluated 20 paragraphs for the presence of false information. As expected, subjects were less likely to report the false information when it was conveyed as logically subordinate rather than central. The results suggest one explanation for deficits in comprehension monitoring and have implications for understanding susceptibility to persuasive communications. 相似文献
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Higher levels of affiliation motivation after exposure to affiliative films are significantly related to higher dopamine concentrations in saliva in one study of 61 college students of both sexes, and in plasma in another study of 47 adults of both sexes. Individuals high in dispositionaln Affiliation, if they also reported high life stress, showed high gains in dopamine concentration in plasma after exposure to an affiliative film significantly more often than other individuals. Since aroused affiliation motivation was not associated with higher concentrations of norepinephrine, epinephrine, or cortisol in either study, it appears likely that dopamine is especially associated with arousal of affiliation motivation, just as norepinephrine has been found to be associated with arousal of power motivation. Thus, different motives may be subserved by different hormones, making it unlikely that all motives lead to the same state of physiological arousal.This research was carried out when all the authors were connected with the Department of Psychology and Social Relations at Harvard University. We acknowledge with thanks the support of the John D. and Catherine T. MacArthur Foundation through a grant to the senior author. 相似文献
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This study was aimed at evaluating the self-control behaviors of hyperactive (HA) and nonhyperactive (NHA) first-grade pupils under conditions of repeated failure on a previously learned concept formation task. Subjects were divided into HA and NHA groups on the basis of their scores on the Conners (1969) Teacher Rating Scale. During the training stage of the experiment the children learned a concept formation task under a schedule of contingent positive reinforcement. In the test stage they performed the same task but under a negative noncontingent reinforcement schedule. The results revealed no differences in initial rate of learning the task between the groups. After the introduction of the negative noncontingent reinforcement schedule, however, the HA group showed a marked decrease in the use of effective problem-solving strategies. The HA children's performance on the concept formation task was accompanied by the emission of negative self-evaluations and solution-irrelevant statements. The NHA group used significantly more statements showing useful goal directed cognitive mediations than the HA children. The results suggested that HA children may have deficits in self-control skills.Grateful acknowledgment is made to the two anonymous reviewers whose insightful comments were very helpful in producing the final form of this paper. 相似文献
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Linda Baker 《Journal of experimental child psychology》1984,38(2):289-311
Nine- and eleven-year-old children differing in reading proficiency read and commented on brief expository passages containing three different types of embedded problems (nonsense words, prior knowledge violations, and internal inconsistencies). Half of the children were specifically instructed as to the types of standards they should apply in order to detect the problems (lexical, external consistency, and internal consistency); the remaining children were simply instructed to look for problems. Both quantitative and qualitative differences in standard use were revealed by the children's comments about all parts of the passages. Older and better readers used more different standards and they used them more frequently than younger and poorer readers. The lexical standard was more likely to be adopted spontaneously than the other two standards and it was the only standard used by a substantial proportion of both younger and poorer readers. Finally, the consistent effects of instruction type indicate that children's evaluation activities were strongly influenced by the amount of guidance received. 相似文献
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Myron Charles Baker Diana F. Tomback Daniel B. Thompson Tad C. Theimer Dana C. Bradley 《Learning and motivation》1984,15(4):428-440
The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects. 相似文献
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The attractiveness bias suggests that people who are more attractive will be positively favored across life outcomes. This study sought to test whether candidate attractiveness, sex, and race, affect perceptions of candidate strength in a job recruitment task. In total, 338 White women (Mage = 20.94 ± 5.65) were asked to make judgements of a potential candidate for an administrative job (resume with candidate photograph). The vignettes differed in terms of candidate ability (strong/weak), sex (male/female), race (Black/White), and attractiveness (attractive/less attractive). Participants rated perceived candidate strength and likelihood to invite for interview. Results showed no significant main effects for attractiveness. However, there was a significant interaction for target attractiveness and race, such that attractive/White candidates were more likely to be invited for interview than less attractive/White candidates. There was also a significant main effect for race such that Black candidates were rated as stronger and more likely to be interviewed. Sensitivity analyses (with nonheterosexual women removed from the sample) also showed a main effect for target sex such that female candidates were favored over male candidates. Overall, these findings provide evidence that attractiveness, sex, and race have important, albeit complex, effects on hiring decisions in the workplace. 相似文献