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121.
48 healthy neonates born to multiparae were randomly assigned to view a moving stimulus either in the horizontal or the upright position, with or without added vestibular stimulation and with or without pacifier sucking. The infant was shown a moving black line inside a strictly controlled visual environment provided by an apparatus which permitted horizontal and upright positioning and displacement of the infant. Visual tracking was recorded by a concealed TV camera positioned at a constant distance and angle from the infants' eyes in both positions. Quality of tracking during each of 4 trials was scored on a 7-point scale. Results indicate that vestibularproprioceptive stimulation provided to the infant either horizontally or semivertically significantly enhanced his visual tracking, whereas the upright position did not. Pacifier sucking also improved his performace.  相似文献   
122.
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124.
To examine the developmental significance of mirrow self-recognition in early childhood, a cross-sectional study with 55 Down's syndrome children was conducted. When their image is altered by rouge on the nose, normal infants by 22 months indicate self-recognition by touching their noses while looking in the mirror. Only a small percentage of Down's syndrome children touched their noses by this age, confirming the expected lag in this development. However, those young Down's syndrome infants with near-normal development quotient did manifest the reaction. In general, when developmental age was equated, the Down's syndrome children showed parallel development to normal children.  相似文献   
125.
First-grade males performed a 30-min visual vigilance task under 5 conditions of auditory background stimulation. The 5 conditions consisted of (1) continuous conversation, in which subjects listened to a tape of conversation spliced so that there were no intervals of silence lasting longer than 3 sec; (2) continuous reverse, in which subjects heard the continuous conversation tape played in reverse; (3) intermittent conversation, in which subjects heard alternating segments of conversation and silence; (4) intermittent reverse, in which subjects heard alternating segments of reverse conversation and silence; and (5) silence control. Compared with silence or continuous stimulation, intermittent stimulation produced better detection regardless of whether or not it was meaningful. High achievers made more correct detections than low achievers, but only in the second and third time periods. Few subjects made errors of commission.  相似文献   
126.
The research reported in this article was carried out as part of a larger prefect investigating the impact of the US Space Program on the American economy. The author describes the influence of governmental programs in space and defense on the growth of the computer and semiconductor industries. Three types of economic impacts are analyzed: the role of the federal government in financing research and development; the importance of the government as a market, particularly in the early stages of an industry's growth; and the extent to which government policy encouraged the entrance of new firms and permitted the survival of companies that might otherwise have failed. The paper also deals with the contribution of Defense and NASA to the acceleration of technological changes and the development of specialized manpower on which the progress of the industry largely depended.The author concludes that large government programs can play an essential role in the growth of high technology industries. The significance of space-defense programs for US semiconductor and computer firms can only be perceived by reviewing each type of impact-economic, technological and manpower. The government's early R & D support, assured demand during startup periods, encouragement of competition, acceleration of technological progress and its facilitating of professional mobility, are the separate impacts which together greatly aided US firms in their rise to a dominant position in the world semiconductor and computer industries.  相似文献   
127.
Victor D Hopper 《Endeavour》1978,2(3):121-126
Measurement of vertical and horizontal wind velocity is of great importance in many contexts, such as investigation of air pollution, weather forecasting, and air-traffic control. In recent years continuously recording acoustic sounders have been developed which give reliable results at reasonable cost: some 200 are now in use in at least 15 countries.  相似文献   
128.
Second graders, fifth graders, and adults participated in 2 experiments designed to study the effects of sorting on subsequent recall of unrelated words. 1 group sorted the items freely, while a second group was constrained to learn the sorting schemes generated by free subjects. In the first experiment, subjects sorted until they reached a criterion of organizational stability. In Experiment 2, sorting was terminated prior to reaching a stable criterion. Recall and output clustering were reduced in Experiment 2, relative to Experiment 1, because of organizational instability. No meaningful differences were found in either experiment in the sorting schemes generated by free subjects in the 3 age groups, nor was there an effect of age of yoking partner on performance of constrained subjects. This result differed from previous research, and it was concluded that the sorting technique diminished differences in organizational behavior usually found between older and younger subjects.  相似文献   
129.
The behavior of narcotics-addicted and nonaddicted newborns on the first 2 days of life was assessed with the Brazelton Neonatal Behavioral Assessment Scale. In addition to classic signs of narcotics abstinence, addicted infants were less able to be maintained in an alert state and less able to orient to auditory and visual stimuli. These deficits were especially pronounced at 48 hours of age. Addicted infants were as capable of self-quieting and responding to soothing intervention as normal neonates, although they were substantially more irritable. These characteristics and addicted infants' greater resistance to cuddling are discussed in terms of their potential impact on early infant-care-giver interaction.  相似文献   
130.
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