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981.
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Mathematics has always played an important role in the education of engineers and production managers. At the present time, the importance of mathematics has increased significantly and it is quite natural that in universities around the world engineering students are taking courses in mathematics which constitute, as a rule, a significant portion of their programme. At the same time, however, the mathematical education of the engineer is far from ideal and its improvement deserves the closest scrutiny. The present article deals with several general aspects of this problem. 相似文献
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Continuity of individual adaptation from infancy to kindergarten: a predictive study of ego-resiliency and curiosity in preschoolers 总被引:2,自引:0,他引:2
In this longitudinal study, individual differences in security of attachment at 18 months and effective autonomous functioning at age 2 years were related to the dimensions of ego-control and ego-resiliency at age 4--5 years. The kindergarten or nursery school teachers of 26 children completed California Child Q-Sorts. The children were also given a short form of the Block's laboratory battery (Banta's curiosity box, level of aspiration, motor impulse control delay of gratification, the Shure and Spivack Preschool Interpersonal Problem-solving Test, and the Lowenfeld mosaics). Following the Blocks, composited ego-resiliency and ego-control scores were derived from each data set. Children earlier classified as securely attached were, as predicted, significantly higher on ego-resiliency on both laboratory and Q-sort composites. They were also higher than anxiously attached infants on 3 independent measures of curiosity. An independently composited index of competence from 2-year tool-using measures also correlated significantly with later resiliency, as did 2-year measures of mothers' support and quality of assistance. The data provide initial links between the infant's quality of attachment, the toddler's effectiveness in a problem-solving situation, and competence during the preschool years. 相似文献
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Conditioned taste aversions produced a moderate, but transient, suppression of schedule-induced polydipsia. This suppression was greater and longer lasting when rats were offered a choice between water and the previously poisoned solution on the polydipsia baseline. A final experiment demonstrated that taste aversions were more effective in suppressing schedule-induced consumption when superimposed on a developing schedule-induced drinking baseline as opposed to a stable pattern of schedule-induced drinking. It was suggested that schedule-induced polydipsia is insensitive to conditioned taste aversions. This conclusion was discussed in terms of schedule-induced alcohol consumption and its potential as an animal model of alcoholism. 相似文献
990.
Rats shocked once by a stationary, wire-wrapped prod mounted on the wall of the test chamber incorporated sand, wooden blocks, or commercial bedding material on the floor of the chamber into a defensive response. They moved the available material toward and over the shock prod in all three conditions, adapting the response topography to the particular demands of the available material. In the sand and bedding conditions, the rats buried the prod by pushing and spraying piles of the material with snout and forepaws, whereas, in the blocks condition they picked up the blocks with their teeth and placed them individually around the prod. In Experiment 2, the rats buried the shock prod with blocks even when they had to first carry the blocks to the prod from the back of the chamber. Thus, conditioned defensive burying is not a simple, reflexive response to objects paired with a painful stimulus: it is a complex behavioral sequence that can vary as a function of the availability of burying materials. 相似文献