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851.
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   
852.
This study examined the extent to which psychologists, when compared to university professors and evening school students, employ individualist values differentially in their responses to vignettes describing males and females. The participants responded to 6 vignettes by choosing initial hypotheses that reflected either utilitarian (tradition-ally masculine) or expressive (traditionally feminine) themes. Two vignettes involved a sex of client manipulation, but neither resulted in a sex of client effect. An analysis of the responses to the remaining 4 vignettes indicated a marked preference for the masculine form of individualism for males, but were evenly divided for females in all three groups. These results suggest that psychologists were just as likely to engage in bias as others.  相似文献   
853.
TIME COURSE OF ACTIVATING BRAIN AREAS IN GENERATING VERBAL ASSOCIATIONS   总被引:2,自引:0,他引:2  
Abstract— Generating a use far a visual word in comparison with reading the word aloud activates frontal attention areas first (170 MS), a left lateral frontal area next (250 ms), and then a left temporoparietal (Wernicke's) area (650 ms). A brief period of practice reduces these activations. If subjects are asked to respond to a word from the same practiced list by giving a novel use, the original activations reappear and are joined by activity similar in location and time to Wernicke's activation but in the right hemisphere. These findings demonstrate the time course of activations of neuroanatomical areas in word processing and indicate a role for the right hemisphere when semantic processing is more difficult, such as in generating a less frequent association in the presence of a highly practiced one.  相似文献   
854.
The development of attitudes and activities of newcomers in the 18 months following the first period of socialization was investigated. At two points in time, persons' preferences for seven work climates were compared with perceived climate. Changes in person-climate fit were assessed, using a squared difference index, after alternative fit-indices were tested with hierarchical regression analysis. Person-climate fit and work attitudes at T1 (eight to ten months after entry) were examined by comparing three groups of respondents who did not change jobs, changed jobs within the organization or changed organizations. Results showed no alpha, beta or gamma changes for the total group of 108 respondents. Alpha changes were only found for respondents who changed jobs. They showed higher ratings for job satisfaction at T2. Finally, work attitudes at T1 were related to turnover. Organizational changers showed higher turnover intentions and higher discrepancies between preferred and perceived risk orientation and work pressure at T1.  相似文献   
855.
Research over the past decade and a half exploring the psychological dimensions of the definition of sexual harassment has converged on a three-factor model: gender harassment, unwanted sexual attention, and sexual coercion. The current study used confirmatory factor analysis to determine whether the most widely used sexual harassment survey, the U.S. Merit Systems Protection Board (USMSPB; 1981) survey, measures this three-factor structure. Data from a sample of the USMSPB's 1988 survey of Federal employees (n= 1070) and from a midwestern university's survey of undergraduates (n= 572) and graduate students, faculty, and staff (n= 575) were analyzed. The three-factor model fit reasonably well in all samples, but two survey items, measuring sexual assault and sexual favors, were weakly related to their respective factors. This model, however, was only marginally stable across female and male subsamples, and gender harassment and unwanted sexual attention had low discriminant validity. Both practical and theoretical implications are discussed.  相似文献   
856.
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   
857.
Mechanical restraints are commonly used to reduce the risks associated with severe self-injurious behavior (SIB), but may result in movement restriction and adverse side effects (e.g., bone demineralization). Restraint fading may provide a method for decreasing SIB while increasing movement and reducing these side effects. In the current investigation, rigid arm sleeves and restraint fading (gradually reducing the rigidity of the sleeves) were used with 3 clients who engaged in hand-to-head SIB. Restraints and fading reduced the hand-to-head SIB of all clients. However, for 1 client, the addition of a water mist procedure further reduced SIB to near-zero levels. For a 2nd client, another form of SIB developed that was not prevented by the rigid sleeves. For a 3rd client, a topography of SIB that was not physically prevented by the rigid sleeves was also reduced when restraints and fading were introduced.  相似文献   
858.
We conducted a functional assessment of problem behaviors of 2 students with developmental disabilities in their classroom environments. Results of the assessments showed that although there were more tantrums in demand than in no-demand conditions, the function of the behavior was to gain attention (positive reinforcement) rather than to avoid or escape demands (negative reinforcement); demand conditions apparently served a discriminative function for the availability of attention. Therefore, intervention was based on the positive reinforcement hypothesis, resulting in a substantial reduction of tantrums for both subjects.  相似文献   
859.
One of the most important skills in soccer is the ability to respond quickly and accurately to the changing demands of the competitive environment (i.e., position of ball, teammates, opponents). A multiple baseline design across 4 male collegiate soccer players was used to determine the effectiveness of an attentional training program on the execution of targeted soccer skills. The treatment included information and laboratory attentional shift exercises followed by practice of attentional shifting skills on the execution of different soccer exercises. Following treatment, the accuracy of execution of the experimental soccer drill improved.  相似文献   
860.
This study evaluated the effectiveness of high-probability requests and time-out as treatments for noncompliance that appeared to be maintained by contingent attention in 2 developmental normal children. The introduction of high-probability requests increased compliance for 1 child but not the other. Time-out was effective with both children, and improvements in compliance were maintained at an 8-week follow-up.  相似文献   
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