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921.
922.
This study indicates that sales volume, stage in the product life cycle, profitability and turnover are all important predictors of the method and magnitude of financial rewards provided by high tech firms to R and D employees. The most favorable situational factors for R and D incentive compensation are a low sales volume high tech company, operating in the growth stage of the product life cycle, with high turnover rates, and capable of linking profitability to incentive rewards such as bonuses. 相似文献
923.
The peak amplitude of EMG activity was measured from the orbicularis oris superior (OOS), orbicularis oris inferior (OOI) and masseter muscles for 3 normal 4-yr.-old children and compared to past data gathered on a group of articulatory disordered children, normal children, and adults. The 4-yr.-olds evidenced greater average peak EMG activity than the other groups, suggesting that speech-sound production becomes more efficient with maturation. Also, levels of variability obtained for the younger children were considerably smaller than for the normal speakers across the three muscles, showing that motor equivalence changes with age whereby the flexibility in the control of articulators increases. The coefficient of variation for the OOI muscle for the disordered children, however, was similar to that for the 4-yr.-olds, while the corresponding data for the other two muscles paralleled those for normal ones. These findings were interpreted as reflecting a delay in the development of speech-motor equivalence that affects certain muscles while sparing others. 相似文献
924.
This experiment concerned the contribution of polydipsia on the temporal discrimination of rats during a fixed-interval 60-sec. schedule. In this study, the timing accuracy of 12 rats which had access to water during training was compared to that of 12 rats which had no water during training. The rats were trained for 25 sessions on an FI 60-sec. schedule. In early sessions before polydipsia was fully developed, no differences existed between the timing accuracy of the water group and no-water group. As the amount of water drunk by the water group increased as the number of sessions increased, a parallel increase was noted in the timing accuracy of the water group. In the final sessions, a significant difference was found between the timing accuracy of rats in the water group and that of those in the no-water group. It was concluded that polydipsia facilitated the development of the temporal discrimination which is characteristic of a fixed-interval 60-sec. schedule. 相似文献
925.
This study was designed to determine possible differences in the cognitive, perceptual, and personal-social development of prematurely and maturely born 3-yr.-olds which might foreshadow later learning problems. The subjects were 40 prematurely born graduates of a neonatal intensive care unit (birth weight less than 2,500 gm, less than 37 wk. gestation) matched on the pair-level with full-term controls on sex, race, post-conceptual age, and socioeconomic background. All subjects were singletons and parity was matched at the group level. No differences were found between the groups on tests of higher mental processes including the General Cognitive, Verbal, Quantitative, and Memory Scales of the McCarthy Scales of Children's Abilities, and researcher-devised measures of problem-solving competence. No differences in parental reports of personal-social development were noted. Prematures did not perform as well as controls on perceptual performance tasks, and this difference was interpreted as reflecting relatively impaired visual-motor coordination. 相似文献
926.
Cross-modal effects on visual and auditory object perception 总被引:1,自引:0,他引:1
927.
928.
929.
930.
W Kallenbach G Küllertz G Fischer 《Psychiatrie, Neurologie, und medizinische Psychologie》1984,36(5):295-302
The investigation of enzyme activity in cerebrospinal fluid has been without relevant results for laboratories analysing spinal fluid. For neurochemical purposes, it is interesting that the Substance P is convered by Depeptidyl-aminopeptidase IV (DP IV), liberating dipeptides. The hydrolysis of nitroanilids of the form Xaa-Pro-NHNp in cerebrospinal fluid was analysed using them as peptidases substrates. Finally a method for measuring the activity was proposed. 相似文献