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871.
Several devices have been developed enabling the blind to adapt to digital and visual displays. Most require extensive training and are relatively expensive. The audio-tactile display described in this paper requires very little training and promises to be inexpensive. Prototypes of the display have been developed for a digital stopwatch, a digital clock, and several electronic calculators. Because the device makes use of electrical impulses to communicate with the blind, it also has numerous potential capabilities as a research tool. The device is based on a panel containing columns of braille digits that are made active through a logic circuit interfacing the braille display with a calculator or other device. The subject scans the braille columns and discovers the digits active in each column when a tone is produced simultaneously with the finger contacting the braille digit. 相似文献
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Jerry D. Harris Bonnie A. Gray Shirley Rees-McGee James L. Carroll Elizabeth T. Zaremba 《Journal of School Psychology》1987,25(4):343-354
School psychologists serving a national, systematic sample of public elementary and secondary schools were surveyed regarding recent referrals. Most referrals were initiated by school staff members (75% of referrals), and the majority occured initially through formal mechanisms (55% of referrals). Most informal requests for assistance or information eventually became, or were thought likely to become, formal referrals. In 92% of cases, the referral agent's initial communication with the psychologist included some designation of what the pupil was doing or not doing that was viewed as problematic. Poor academic performance was of primary concern in 52% of referrals and social/emotional problems in 31%. More boys were referred than girls, and one-half of referrals from the elementary grades involved pupils in grades K-2. Frequency of referral and reason for referral were not independent of pupil's grade or sex. Reason for referral was independent of time of year (October vs. May) and geographical region. 相似文献
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Previous research suggests that gut distension by ingested bulk plays an important role in the regulation of food intake in gastropod molluscs. The present study tested whether the bilateral stomatogastric nerves which innervate the esophagus and crop in Pleurobranchaea form a neural pathway carrying information about gut distension to the central nervous system. The posterior branches of the paired stomatogastric nerves were surgically exposed and sectioned in seven experimental animals while the nerves were simply exposed and not sectioned in seven sham-operated control animals. In three, subsequent, daily feeding sessions, the experimental subjects consumed a greater amount of food in terms of percentage of body weight than the control subjects. The experimental animals also gained a greater percentage of body weight and later were found to contain much more food within their guts. The results support the hypothesis that stretch receptors which innervate the gut and which have axons in the stomatogastric nerves form an important negative feedback pathway for the control of feeding in the sea slug. 相似文献
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Confirmatory factor analyses of the 15 cognitive abilities tests from the Hawaii Family Study of Cognition were conducted on between-family (BF) means and within-family (WF) differences for 370 AEA (Americans of European ancestry) and 116 AJA (Americans of Japanese ancestry) sibling pairs. Difference chi-square significance tests, goodness-of-fit indices, and congruence coefficients for the estimated loadings on four specific cognitive abilities factors and on the second-order general intelligence factor nearly all indicated that the between-family factor structures were not significantly different from the within-family structures for both AEA and AJA siblings (the AEA and AJA structures were also not significantly different). The similarity of the BF and WF structures suggests that the genetic and environmental influences underlying cognitive abilities are “intrinsic” in nature, that is, not just due to between-family differences in culture, status, values, and fortuitous cross-assortative mating. 相似文献