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151.
152.
Abstract ——We report the first experimental study of the effect of long–term (over 2 years) exposure to a stressor on cellular immune response Forty–three male cynomolgus monkeys were randomly assigned to stable or unstable social conditions for 26 months The proportion of time spent in affiliative behaviors was assessed by observations made twice weekly T–cell immune response (mitogen–stimulated cell proliferation) was assessed weekly for 3 weeks immediately following the 26–month manipulation The possibility that affiliative behavior represents an attempt to cope with social stress was supported by greater affiliation among animals m the unstable condition than in the stable condition Animals in the unstable condition also demonstrated relatively suppressed immune response More affiliative animals showed enhanced immune response, with the beneficial effects of affiliation occurring primarily among unstable animals The data are interpreted as consistent with the stress–buffering hypothesis, that IS, affiliation protects animals from the potentially pathogenic influences of chronic social stress  相似文献   
153.
154.
A set of programs has been developed to allow efficient operator control over the recording of physiological and behavioral measures in experiments of several hours’ duration. Important features include menu-driven selection among possible measurements, minimal data loss in the event of system failure, on-line correction or deletion of incorrect data both during and after collection, and selective reporting of individual statistics and time periods. These programs can be extended to include new measurements with minimal interference with existing measurements.  相似文献   
155.
For longitudinal studies of rats’ consumption of ethanol, water, and food, we require manual entry of directly observed measurements, consolidation with computer-collected measurements, quick computation of derived statistics, and the export of selected data for further analysis and graphing. As in a spreadsheet, our solution propagates changes in data values through all computations dependent on them but, as in a relational database, maintains data in discrete disk records indexed by day and cage, in which the format of these records is also described by records stored in the same database. During manual data updates, each day’s data are presented in a spreadsheet-like format but with more control over data entry validity than a spreadsheet typically affords. Experimental integrity is further enhanced by producing printed worksheets for data entry, assignment of rats to treatments, and printed injection instructions directly from such customized data files.  相似文献   
156.
While wearing laterally displacing prisms, Ss were required to align a spot of light to the phenomenal straightahead. These measurements were obtained at the beginning and at the end of an exposure to prismatic displacement. In addition, Ss either actively controlled movement of the spot of light, or movement was manipulated by E under the direction of the S. Aftereffects were determined by having S position the spot of light with normal vision at the beginning of the experiment and after each measurement obtained under prism viewing. Ss in the darkened room condition who were required to align the spot of light actively showed a significant aftereffect in the direction of prismatic displacement both at the beginning and at the end of the exposure period. No difference in the degree of adaptation was found between those measurements at the beginning and at the end of the exposure period. No significant aftereffects were found when the room was illuminated during prism exposure or when E controlled movement of the light source.  相似文献   
157.
An adaptive threshold estimation procedure, PEST, has been extended to track sensitivity to many independent signals simultaneously within a single experimental run. This paradigm has been implemented on a PDP-8/S computer, and enables investigation of a number of otherwise experimentally intractible substantive problems. The logic of the new experimental paradigm is described, and some examples are given of its use in auditory research. Results of some computer simulations show the relative efficiency of the procedure and evaluate alternative ways to summarize data.  相似文献   
158.
A method of systematic task analysis is applied to the problem of designing a sequence of learning objectives that will provide an optimal match for the child's natural sequence of acquisition of mathematical skills and concepts. The authors begin by proposing an operational definition of the number concept in the form of a set of behaviors which, taken together, permit the inference that the child has an abstract concept of "number". These are the "objectives" of the curriculum. Each behavior in the defining set is then subjected to an analysis that identifies hypothesized components of skilled performance and prerequisites for learning these components. On the basis of these analyses, specific sequences of learning objectives are proposed. The proposed sequences are hypothesized to be those that will best facilitate learning, by maximizing transfer from earlier to later objectives. Relevant literature on early learning and cognitive development is considered in conjunction with the analyses and the resulting sequences. The paper concludes with a discussion of the ways in which the curriculum can be implemented and studied in schools. Examples of data on individual children are presented, and the use of such data for improving the curriculum itself, as well as for examining the effects of other treatment variables, is considered.  相似文献   
159.
Preschool children enrolled in same- and mixed-age day care classrooms were observed during free play to examine patterns of social and play behavior. In mixed-age rooms, there was more interactive-functional play, for both older and younger children, more dramatic play and negative interactions for younger children, and a tendency for older children to be onlookers. In the same-age rooms, there was more conversation and more parallel-functional interaction for both older and younger children. While previous research has emphasized the benefits of mixed-age rooms, the current research indicates that some costs may also be involved.  相似文献   
160.
A microprocessor-controlled clinical tromometer has been developed to permit routine monitoring of disease processes where tremor is a principal sign and in behavior studies where tremor may be used to index anxiety, stress, or response to Ethan. Emphasis is placed on the measurement technique and the design and construction of the device. The important role played by the microprocessor in providing for human factoring of the instrument to make it compatible with the clinical setting is examined.  相似文献   
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