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
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
Four male subjects responded on a multiple schedule in which responding was maintained by a random interval 20-sec (RI20) schedule of point presentation. Responding was suppressed in alternating components by an added variable ratio 30 (VR30) schedule of point subtractions. Each component was accompanied by distinctive stimulus lights. Subjects were exposed to the multiple schedule from the initial session. Two subjects experienced four 50-min sessions daily (Experiment 1) and the other two subjects participated in one 50-min session daily (Experiment 2). Once responding in the punished components had stabilized, responding in the nonpunished components continued to increase across sessions. Nonpunished responding did not stabilize even after as many as 36 sessions. These results are discussed in the context of previous studies using animals which employed multiple schedules with punished and nonpunished response contingencies.
Within the Euro-American community of philosophers relating hermeneutics to science there is a considerable disagreement about where hermeneutics may be located. The older traditions hold that hermeneutics apply to and are limited to the social, cultural, and historical dimensions of science. But newer approaches claim that hermeneutics applies to the very praxis of science and to the constitution of scientific objects. This paper sides with the latter perspective and argues that a tendency to retain vestigial positivist interpretations of science keeps the older tradition from seeing hermeneutics as deeply embedded in science praxis. After arguing this point historically, I turn to a hermeneutic recuperation of science, first by drawing from the hermeneutic approach of Joseph Rouse, and then by the hermeneutic constructionism of Bruno Latour. I finally turn to what I term technoconstruction in science, particularly in imaging processes, to show concrete cases of the hermeneutic preparation of scientific objects. I conclude that contemporary science has exceeded its earlier modernist framework and now operates in a constructionist-hermeneutic framework. 相似文献
This study describes the results of a retrospective review of patients' charts who had an advanced directive (AD) and who were hospitalized in a tertiary, acute care teaching hospital. The purpose of the review was to understand from clinical, sociological, ethical and legal perspectives the nature and utility of ADs. Findings and implications of the review are discussed in terms of: patient demographics; diagnoses; quality of ADs; influence of ADs on clinical decisions; and legal aspects of ADs. 相似文献
The authors summarise the findings of four recent experiments whichexamined childrens capacity to remember a particular occurrence of arecurring event. Issues discussed include the timing of the interview, thetype of errors, the questioning techniques, the age of the child, theconsistency of the childs account, and the impact of an interveninginterview. Implications for professionals who conduct investigatory orevidentiary interviews with child witnesses are discussed and suggestionsfor future research are also offered. 相似文献
Several current models of human parsing maintain that initial structural decisions are influenced (or tuned) by the listener's or reader's prior contact with language. The precise workings of these models depend upon the grain, or level of detail, at which previous exposures to language are analyzed and used to influence parsing decisions. Some models are premised upon the use of fine-grained records (such as lexical cooccurrence statistics). Others use coarser measures. The present paper considers the viability of models based exclusively on the use of fine-grained lexical records. The results of several studies are reviewed and the evidence suggests that, if they are to account for the data, experience-based parsers must draw upon records or representations that capture statistical regularities beyond the lexical level. This poses problems for several parsing models in the literature.Aspects of this work were supported by ESRC grant No. R0023 4062 to Don Mitchell, by a Spanish Government grant DGICVT No. PB-92-0656-C04-02 to Fernando Cuetos, and by the Belgian National Fonds voor Wetenschappelijk Onderzoek, of which Marc Brysbaert is a Research Associate. We are grateful to Chuck Clifton, Barbara Hemforth, Martin Pickering, Matt Traxler, and an anonymous reviewer-all of whom made helpful comments on an earlier draft of the paper. 相似文献
Three field studies investigated the effects of post-exposure cognitions on person identification. Subjects' beliefs that they could identify someone were significantly increased by the presentation of new information and the rehearsal of old information about the person. Misidentification errors increased as the lengths of the initial exposure duration increased and when subjects received additional contextual information about the target. These frequent misidentifications may reflect the misattribution of familiarity from enhanced contextual knowledge to familiarity arising from perceptual knowledge. Further, performance was enhanced when the identification task capitalized on 'transfer-appropriate rehearsal' post-event strategies. Ancillary findings contradicted research on 'verbal overshadowing', and the relationship between identification accuracy and confidence. The results were generalized to real-world situations that encourage post-event cognitions by eyewitnesses. 相似文献