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Real-time clock strategies are described for microcomputers in behavioral research. Software-oriented and hardware-oriented counters are described in both free-running and strobed modes. An example of a clock using the Intel 8253 is given, along with driving software in 8080 assembly code and hardware for the S-100 bus.  相似文献   
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An inverse relationship was found between the number of parental visits an institutionalized retarded child received and the distance of the parental home from the institution. When the natural parents were living together, the retarded child was shown to receive more visits than when the child's parents were separated or one parent was deceased. Single mothers were found to be living significantly closer to the facility than single fathers. Single fathers appeared to put more effort into visiting, since they visited just as often as the mothers, but had to travel further distances than the mothers to do so. Visitation frequency followed a curvilinear pattern, decreasing uniformly from 20–60 miles (from 0–20 miles visitation frequency is uniform), and then leveling off.  相似文献   
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Pigeons' keypecks were reinforced with grain on the average of once per minute by schedules that maintained low response rates and by schedules that maintained high response rates. During these schedules, a fixed-duration conditioned stimulus (CS) ranging from 7.5 to 120 sec in duration across conditions terminated with response-independent food. Response rates during the CS were inversely related to CS duration. The rates and the temporal patterns of responding during the shortest CS were similar whether the ongoing schedule maintained high response rates or low response rates. As CS duration increased, the rate and pattern of responding during the CS converged on the rate and pattern of responding maintained by the baseline schedule. These data indicate that changes in responding during stimuli that signal response-independent reinforcement are not homogeneous throughout the CS; that response measures, such as “suppression ratios”, which presume homogeneity may mislead us; and that conditioned suppression and conditioned enhancement may be better talked about in terms of species-specific approach and avoidance than in terms of emotional states.  相似文献   
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Laboratory dogs were trained to press a response panel to postpone shocks during daily one-hour avoidance conditioning periods. Each dog was also confined in the experimental environment for 5 hours prior to the avoidance periods. Blood pressure and heart rate were monitored continuously during these experiments from chronically indwelling arterial catheters. Extended training resulted in the emergence of a cardiovascular response pattern during the pre-avoidance interval characterized by gradual increases in blood pressure together with decreases in heart rate. Elevations in both blood pressure and heart rate were sustained during the avoidance periods. During sessions in which alpha adrenergic activity was suppressed by phenoxybenzamine, absolute levels of blond pressure were found to be lower than during control (non-drug) sessions, but a progressive rise in blood pressure continued to be observed during pre-avoidance. These results suggest that sustained cardiovascular responses during avoidance periods are associated with activation of the sympathetic nervous system, but that the gradual rise in blood pressure during pre-avoidance is due to other factors.  相似文献   
96.
The concept of standards lacks clarity because it is applied both to concrete specifications and to the assessment of quality. Confusion is reduced by introducing the notion of interchange expectancy. distinguishing transfer, coupling, and market success as components. Transfer expectancy depends upon the products to be transported or exchanged, but when there is a need to estimate transfer expectancy, a combination of technical standards and performance standards must be applied. Though performance standards are intended to produce quality, the quality of the instrumentation to measure performance standards is often neglected. The development of high-quality performance standards first requires the delineation of the relevant dimensions of performance quality. The process of giving precision to performance standards may lead to the emergence of more acceptable technical standards. To illustrate some of these points, data is presented from the CONDUIT system for quality evaluation of computer-based curriculum materials. The performance quality of these products includes the dimension of transfer expectancy, as well as educational and scientific merit. Increased specification and impact of technical standards may provide greater incentives to authors and hence lead to the invention of products which have higher educational and scientific quality.  相似文献   
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Neuropsychology Review - Attention problems are thought to be a hallmark feature of prenatal alcohol exposure (PAE). Despite decades of research however, these findings have never been pooled to...  相似文献   
100.
Although research has identified effective evidence-based depression prevention interventions for diverse youth, little is known about how the intervention process unfolds with immigrant family youth. This study utilized a qualitative approach to explore cultural and clinical differences in the implementation of Interpersonal Psychotherapy–Adolescent Skills Training (IPT-AST) in two schools, one serving youth from primarily immigrant, Asian American families and the second, youth from mostly nonimmigrant, non-Hispanic White families. A total of 131 IPT–AST sessions were audio recorded, transcribed, and coded for presence and patterns of cultural and clinical constructs. Results revealed that sessions with immigrant family youth were more likely to contain discussions of interpersonal problems characterized by estrangement, goals of spending time together with important others, mentions of emotion suppression and academic achievement expectations, conversations about acculturation, differences in value orientation, and discomfort with implementing new intervention skills. Dialogue from interventionist and youth exchanges is presented to illustrate how these themes emerged and were addressed by interventionists in a culturally responsive manner. The study highlights how IPT–AST with immigrant family and Asian American youth may unfold differently compared to youth from nonimmigrant families. Implications of findings for providers are discussed.  相似文献   
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