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61.
The interaction of light with surfaces results in a number of lighting effects that may serve as valuable visual cues. Previous research on shadows has shown them to be effective in determining the three-dimensional (3-D) layout of a scene, but interreflections have been ignored as cues for spatial layout. Interreflections as well as shadows may help to disambiguate the 3-D layout of objects by providing information about an object's contact with a surface. We generated computer images of a box on an extended textured ground plane that was either in contact with the ground or was slightly above the ground. Images were rendered for four conditions: (1) no shadow + no interreflection, (2) shadow only, (3) interreflection only, and (4) shadow + interreflection. A photometrically incorrect condition was also included. The participants rated the degree of contact for each image on a scale, which was used to generate receiver operating characteristic (ROC) curves and a measure of sensitivity. In the images with no shadows or interreflections, the participants performed at chance levels. Interreflections, shadows, and a combination of interreflections and shadows all resulted in high sensitivity for judging object contact. More important, information from shadows and interreflections can be combined, resulting in near-perfect judgment of surface contact. Interreflections and shadows can be effective cues for object contact.  相似文献   
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Pigeons' key pecks produced food under second-order schedules of token reinforcement, with light-emitting diodes serving as token reinforcers. In Experiment 1, tokens were earned according to a fixed-ratio 50 schedule and were exchanged for food according to either fixed-ratio or variable-ratio exchange schedules, with schedule type varied across conditions. In Experiment 2, schedule type was varied within sessions using a multiple schedule. In one component, tokens were earned according to a fixed-ratio 50 schedule and exchanged according to a variable-ratio schedule. In the other component, tokens were earned according to a variable-ratio 50 schedule and exchanged according to a fixed-ratio schedule. In both experiments, the number of responses per exchange was varied parametrically across conditions, ranging from 50 to 400 responses. Response rates decreased systematically with increases in the fixed-ratio exchange schedules, but were much less affected by changes in the variable-ratio exchange schedules. Response rates were consistently higher under variable-ratio exchange schedules than tinder comparable fixed-ratio exchange schedules, especially at higher exchange ratios. These response-rate differences were due both to greater pre-ratio pausing and to lower local rates tinder the fixed-ratio exchange schedules. Local response rates increased with proximity to food under the higher fixed-ratio exchange schedules, indicative of discriminative control by the tokens.  相似文献   
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The Comprehensive Services Act for At Risk Youth and Families of Virginia (CSA), is a service, funding, and organizational reform initiative designed to improve the provision of child centered and family focused services within a community setting. We conducted this study in order to assess the feasibility of applying utilization management principles to the CSA in order to improve the appropriateness, quality, and cost effectiveness of this service delivery system. Data were gathered through focus groups, surveys, clinical profiling, and analysis of costs, and service utilization. While overall program costs increased since inception of the program, the costs per child served rose less than the rate of inflation. CSA appeared to be serving children with a high degree of emotional and behavioral difficulties. There was considerable variation among localities in placement patterns. A majority of survey and focus group respondents were willing to consider the application of utilization management principles to the CSA as long as decision making remained within localities. We concluded that there is a constructive role for utilization management approaches to improve the appropriateness and quality of services as well as enhancing efficiency in child mental health.  相似文献   
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Menopause is a normative life transition that is experienced by virtually all women, yet remains poorly understood. The dominance of the biomedical model results in a unidimensional definition of menopause as a biological event, ignoring the influence of cultural and psychosocial factors. Counselors who use an integrative approach can not only provide accurate biomedical information but also conceptualize menopause as a normative midlife transition. The purpose of this article is to provide a foundation in biomedical issues and to consider how these independently, and in interaction with cultural and psychosocial factors, influence the experience of menopause.  相似文献   
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The purpose of the current study was to develop and evaluate a measure of maternal reward responsivity in parenting. Deficits in reward responsivity, a common feature of depression, may contribute to maladaptive parenting behaviors. Reward responsivity is an individual difference in reactivity to pleasurable stimuli and represents a key motivational component that could contribute to the frequency and quality of mothers’ interactions with their infants. However, there is currently no measure of reward responsivity in parenting, which would be necessary to evaluate the link between mother reward responsivity, behaviors towards their infant, and infant behavior. Therefore, the current study reports on the development and initial evaluation of a self-report measure of reward responsivity in parenting, the Mother Inventory of Reward Experience (MIRE). We evaluated the MIRE among 200 mothers (M?=?28.45, SD?=?5.50) recruited from a pediatric primary care center. After item analysis, 22 items were retained and displayed high internal consistency reliability and test re-test reliability. Convergent validity was established via a significant correlation with global reward responsivity. Concurrent validity was established via significant correlations with depressive symptoms, parenting stress, and child behavior problems. Incremental validity of the MIRE over a measure of global reward responsivity was supported. These results support the reliability and validity of the MIRE as a measure of reward responsivity in parenting.  相似文献   
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The purpose of the present study was to assess the potential of exergame training based on physically simulated sport play as a mode of physical activity that could have cognitive benefits for older adults. If exergame play has the cognitive benefits of conventional physical activity and also has the intrinsic attractiveness of video games, then it might be a very effective way to induce desirable lifestyle changes in older adults. To examine this issue, the authors developed an active video game training program using a pretest-training-posttest design comparing an experimental group (24 × 1 hr of training) with a control group without treatment. Participants completed a battery of neuropsychological tests, assessing executive control, visuospatial functions, and processing speed, to measure the cognitive impact of the program. They were also given a battery of functional fitness tests to measure the physical impact of the program. The trainees improved significantly in measures of game performance. They also improved significantly more than the control participants in measures of physical function and cognitive measures of executive control and processing speed, but not on visuospatial measures. It was encouraging to observe that, engagement in physically simulated sport games yielded benefits to cognitive and physical skills that are directly involved in functional abilities older adults need in everyday living (e.g., Hultsch, Hertzog, Small, & Dixon, 1999).  相似文献   
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We argue that consumers with high self-brand connections (SBC) respond to negative brand information as they do to personal failure — they experience a threat to their positive self-view. After viewing negative brand information, high (vs. low) SBC consumers reported lower state self-esteem. Consumers with high SBC also maintained favorable brand evaluations despite negative brand information. However, when they completed an unrelated self-affirmation task, they lowered their brand evaluations the same as low SBC consumers. This finding suggests that high SBC consumers' reluctance to lower brand evaluation might be driven by a motivation to protect the self rather than the brand.  相似文献   
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