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901.
Sexuality education for children and young adults is one of the most heavily debated issues facing policy-makers, national AIDS program planners, and educators, provoking arguments over how explicit education materials should be, how much of it there should be, how often it should be given, and at what age instruction should commence. In this context, the World Health Organization's Global Program on AIDS' Office of Intervention Development and Support commissioned a comprehensive literature review to assess the effects of HIV/AIDS and sexuality education upon young people's sexual behavior. 52 reports culled from a search of 12 literature databases were reviewed. The main purpose of the review is to inform policy-makers, program planners, and educators about the impact of HIV and/or sexuality education upon the sexual behavior of youth as described in the published literature. Of 47 studies which evaluated interventions, 25 reported that HIV/AIDS and sexuality education neither increased nor decreased sexual activity and attendant rates of pregnancy and sexually transmitted diseases (STDs). 17 reported that HIV and/or sexuality education delayed the onset of sexual activity, reduced the number of sex partners, or reduced unplanned pregnancy and STD rates Only 3 studies found increases in sexual behavior associated with sexuality education. Inadequacies in study design, analytic techniques, outcome indicators, and the reporting of statistics are discussed.  相似文献   
902.
present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.  相似文献   
903.
In two studies, the construct (convergent and discriminant) validity and test-retest reliability of a date rape decision-latency measure was examined. In Study 1, 174 college men completed measures related to sexual aggression and listened to an audiotaped simulation of a date rape, during which cues of nonconsent and force gradually escalated over time. Participants were instructed to respond, by pressing a button which recorded the latency of their decisions in seconds, if and when they believed the man depicted in the scenario should stop his sexual advances. Results demonstrated positive associations between prolonged decision latencies and sexually aggressive behavior, calloused sexual beliefs, acceptance of interpersonal violence, and sexual promiscuity. In Study 2, initial results were cross-validated in a sample of 102 college men, and discriminant validity was established as decision latencies were unassociated with measures of social desirability, alcohol consumption and drug use. Test-retest reliability assessed over a 2-week interval was .87.The authors wish to thank Alan Gross and Brian Marx for providing the audiotaped stimulus materials, Richard Marsh for writing the decision-latency computer program, Jason Hicks for assisting with programming, and the undergraduate research assistants for serving as experimenters.  相似文献   
904.
Our everyday, basic understanding of people's mental stales and behaviors has recently been a lively topic of debate m the social science. This article addresses whether some aspects of our. European-American theory of mind are universal, by examining ethnographic and experimental reports of cultural variation. Implications of the variation for nativist theories of development are discussed and research strategies to augment our understanding are proposed.  相似文献   
905.
Abstract— Becoming a proficient symbol user is a universal developmental last in the first years of life, but delecting and mentally representing symbolic relations can be quite challenging for young children To test the extent to which symbolic reasoning per se is problematic, we compared the performance of 2-year-olds in symbolic and nonsymbolic versions of a search task. The children had to use their knowledge of the location of a toy hidden in a room to draw an inference about where to find a miniature toy in a scale model of the room (and vice versa) Children in the nonsymbolic condition believed a shrinking machine had caused the room to become the model They were much more successful than children in the symbolic condition, for whom the model served as a symbol of the room The symbol understanding and use.  相似文献   
906.
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
907.
The primary objective of the present investigation was to examine adaptive functioning in the families of patients with a wide range of psychiatric disorders. Seven dimensions of family functioning, as measured by the Family Assessment Device (FAD), were compared across families of patients with a schizophrenia spectrum disorder (n = 61 ), bipolar disorder (n = 60 ), major depression (n = 111 ), anxiety disorder (n = 15 ), eating disorder (n = 26 ), substance abuse disorder (n = 48 ), and adjustment disorder (n = 46 ). Families in each psychiatric group were also compared to a control group of nonclinical families (N = 353 ). Results indicated that regardless of specific diagnosis, having a family member in an acute phase of a psychiatric illness was a risk factor for poor family functioning compared to the functioning of control families. However, with few exceptions, the type of the patient's psychiatric illness did not predict significant differences in family functioning. Thus, having a family member with a psychiatric illness is a general stressor for families, and family interventions should be considered for most patients who require a psychiatric hospitalization for either the onset of, or an acute exacerbation of, any psychiatric disorder.  相似文献   
908.
Tustin (1994) recently observed that an individual's preference for one of two concurrently available reinforcers under low schedule requirements (concurrent fixed-ratio [FR] 1) switched to the other reinforcer when the schedule requirements were high (concurrent FR 10). We extended this line of research by examining preference for similar and dissimilar reinforcers (i.e., those affecting the same sensory modality and those affecting different sensory modalities). Two individuals with developmental disabilities were exposed to an arrangement in which pressing two different panels produced two different reinforcers according to progressively increasing, concurrent-ratio schedules. When two dissimilar stimuli were concurrently available (food and a leisure item), no clear preference for one item over the other was observed, regardless of the FR schedules in effect (FR 1, 2, 5, 10, and 20). By contrast, when two similar stimuli were concurrently available (two food items), a clear preference for one item emerged as the schedule requirements were increased from FR 1 to FR 5 or FR 10. These results are discussed in terms of implications for conducting preference assessments and for selecting reinforcers to be used under training conditions in which response requirements are relatively high or effortful.  相似文献   
909.
910.
We examined self- and cross-citation practices in JABA and JEAB from 1983 through 1992. Mean levels of self-citation for JABA and for JEAB were 22.6% and 36.1%, respectively. Overall, 2.4% of JABA citations were JEAB articles, and 0.6% of JEAB citations were JABA articles, which suggests limited integration of basic and applied research.  相似文献   
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