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We investigated the effects of gestational age at birth on behavioral and electrophysiological measures of 135 medically healthy infants, studied at 42 weeks postconception, and stratified into 3 groups--early-born preterms, 26-32 weeks (n = 55); middle-group preterms, 33-37 weeks (n = 43); and fullterms, 38-41 weeks (n = 37). Subjects were studied behaviorally with the Assessment of Preterm Infants' Behavior (APIB) and electrophysiologically with brain electrical activity mapping (BEAM). Fullterms showed significantly better behavioral function than both preterm groups. Less difference was found between the preterm groups. EEG spectral and photic evoked response were of significantly less amplitude for the preterms than the fullterms. Path analysis showed gestational age effects on behavioral (3 of 6) and electrophysiological (13 of 17) variables due to postnatal complications. We conclude that some differences attributable to gestational age at birth are explained by the cumulative effect of minor but unavoidable complications associated with premature birth. We speculate that remaining effects may result from developmentally inappropriate sensorimotor stimulation consequent to the premature experience of an extrauterine environment. 相似文献
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This study was an attempt to encourage middle school pupils to use time spent on topic (project) work to better effect. They were taught some elements of correspondence training which required them to think ahead, to plan carefully what they were going to do in a certain time period and to make a forecast. At the end of each working session, they were required to look back at what they had achieved and to discuss the outcomes with a partner in terms of their success at forecasting and in achievement. Especially among the more able pupils, there were marked improvements in both quantity and quality of work produced 相似文献
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Frank A. Farris 《PRIMUS》2017,27(8-9):827-844
AbstractThe domain-coloring algorithm allows us to visualize complex-valued functions on the plane in a single image—an alternative to before-and-after mapping diagrams. It helps us see when a function is analytic and aids in understanding contour integrals. The culmination of this article is a visual discovery and subsequent proof of the Argument Principle, which relates the count of poles and zeros of a meromorphic function inside a contour to the accumulated change in argument of the function around the contour. Throughout, I offer connections to standard learning goals of courses in complex variables. 相似文献
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This introductory essay reviews the key contributions of David Teece's landmark paper “Profiting from Innovation” published in research policy in 1986. It summarises the contributions of each of the papers in the special issue. It then offers some perspectives on the key themes emerging from these papers, and on the broader challenges facing researchers, strategists and policymakers in the field of technology innovation today. 相似文献
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Although the principle of holography was conceived as long ago as 1947, interest was limited until the advent of the laser in 1960 made possible the off-axis holography widely used today. Since then holography has found many applications and become so well known outside the laboratory as to be a recognized art form. Within the last few years considerable progress has also been made in acoustic holography. 相似文献
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Supplemental instruction classes have been shown in many studies to enhance performance in the supported courses and even to improve graduation rates. Generally, there has been little evidence of a differential impact on students from different ethnic/racial backgrounds. At San Francisco State University, however, supplemental instruction in the Introductory Biology I class is associated with even more dramatic gains among students from underrepresented minority populations than the gains found among their peers. These gains do not seem to be the product of better students availing themselves of supplemental instruction or other outside factors. The Introductory Biology I class consists of a team-taught lecture component, taught in a large lecture classroom, and a laboratory component where students participate in smaller lab sections. Students are expected to master an understanding of basic concepts, content, and vocabulary in biology as well as gain laboratory investigation skills and experience applying scientific methodology. In this context, supplemental instruction classes are cooperative learning environments where students participate in learning activities that complement the course material, focusing on student misconceptions and difficulties, construction of a scaffolded knowledge base, applications involving problem solving, and articulation of constructs with peers. 相似文献