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41.
Paul Brna Alan Bundy Tony Dodd Marc Eisenstadt Chee Kit Looi Helen Pain Dave Robertson Barbara Smith Maarten van Someren 《Instructional Science》1991,20(2-3):111-133
In this paper we introduce the concept of a Prolog programming technique. This concept is then distinguished both from that of an algorithm and that of a programming cliché. We give examples and show how a knowledge of them can be useful in both programming environments and in teaching programming skills. The extraction of the various techniques is outlined. Finally, we discuss the problem of representing techniques where we conclude that the most promising approach is the development of a suitable meta-language. 相似文献
42.
D. W. Fulker L. R. Cardon J. C. Defries W. J. Kimberling B. F. Pennington S. D. Smith 《Reading and writing》1991,3(3-4):299-313
A simple extension of the DeFries and Fulker multiple regression model for twin analysis is applied to the problem of detecting linkage in a quantitative trait. The method, employing sib pairs, is based on that of Haseman and Elston. Reading data from 19 extended pedigrees were analyzed employing RLFPs as markers on chromosome 15 and using the widely available statistical applications software package, SAS. A number of possible linkages were detected, indicating that this approach is both powerful and effective, especially in the case of selected samples. Detecting genotype-environment interaction and the issue of power are briefly discussed. The programs used are available upon request. 相似文献
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44.
Janet M. Batzli Amber R. Smith Paul H. Williams Seth A. McGee Katalin Dósa Jesse Pfammatter 《CBE life sciences education》2014,13(3):410-424
Genetics instruction in introductory biology is often confined to Mendelian genetics and avoids the complexities of variation in quantitative traits. Given the driving question “What determines variation in phenotype (Pv)? (Pv=Genotypic variation Gv + environmental variation Ev),” we developed a 4-wk unit for an inquiry-based laboratory course focused on the inheritance and expression of a quantitative trait in varying environments. We utilized Brassica rapa Fast Plants as a model organism to study variation in the phenotype anthocyanin pigment intensity. As an initial curriculum assessment, we used free word association to examine students’ cognitive structures before and after the unit and explanations in students’ final research posters with particular focus on variation (Pv = Gv + Ev). Comparison of pre- and postunit word frequency revealed a shift in words and a pattern of co-occurring concepts indicative of change in cognitive structure, with particular focus on “variation” as a proposed threshold concept and primary goal for students’ explanations. Given review of 53 posters, we found ∼50% of students capable of intermediate to high-level explanations combining both Gv and Ev influence on expression of anthocyanin intensity (Pv). While far from “plug and play,” this conceptually rich, inquiry-based unit holds promise for effective integration of quantitative and Mendelian genetics. 相似文献
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46.
CRABTREE Vincent P. AZORIN-PERIS Vincent ECHIADIS Angelos SMITH Peter R. 《浙江大学学报(A卷英文版)》2007,8(6):916-920
Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-invasive PPG technique to detect the blood pulse signal on toe with infrared (IR) photo sensor. A protocol consisting of two postures, i.e., supine and 45° reclining, was designed to conduct laboratory trial in this study. During the period of performing the protocol of these postures, the lower limb was passively raised from the heights of 10 cm to 60 cm randomly and individually with sponge blocks underneath the foot. Results: In the supine posture, the higher the foot was passively raised, the more the blood PPG signal decreased. In the 45° reclining posture, the blood PPG signal increased at the beginning and then decreased in the foot height position from 10 cm to 60 cm. In both postures the normalized AC signal changes significantly while the normalized DC signal changes little. Conclusion: The toe PPG signals can obviously indicate the regulated blood volume change with the designated postural procedures due to the heart level position. 相似文献
47.
Linda J. Graham 《Cambridge Journal of Education》2012,42(2):163-176
A significant gap exists in the Australian research literature on the disproportionate over-representation of minority groups in special education. The aim of this paper is to make a contribution to the research evidence-base by sketching an outline of the issue as it presents in Australia’s largest education system in the state of New South Wales. Findings from this research show that Indigenous students are equally represented in special schools enrolling students with autism, physical, sensory, and intellectual disabilities, but significantly over-represented in special schools enrolling students under the categories of emotional disturbance, behaviour disorder and juvenile detention. Factors that might influence the disproportionate over-representation of Indigenous children and young people are discussed, and based on these observations, some practical implications for policy and practice are provided. 相似文献
48.
Andrew J. Greene Michael H. Dickson Floren Colloud Richard M. Smith 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):302-317
The effect of anthropometric differences in shank to thigh length ratio upon timing and magnitude of joint power production during the drive phase of the rowing stroke was investigated in 14 elite male rowers. Rowers were tested on the RowPerfect ergometer which was instrumented at the handle and foot stretcher to measure force generation, and a nine segment inverse dynamics model used to calculate the rower's joint and overall power production. Rowers were divided into two groups according to relative shank thigh ratio. Time to half lumbar power generation was significantly earlier in shorter shank rowers (p = 0.028) compared to longer shank rowers, who showed no lumbar power generation during the same period of the drive phase. Rowers with a relatively shorter shank demonstrated earlier lumbar power generation during the drive phase resulting from restricted rotation of the pelvic segment requiring increased lumbar extension in these rowers. Earlier lumbar power generation and extension did not appear to directly affect performance measures of the short shank group, and so can be attributed to a technical adaptation developed to maximise rowing performance. 相似文献
49.
ABSTRACTIn this paper, we draw on the ‘dilemma of difference’ to discuss the dangers and affordances of diagnosis within two of the most prevalent, yet under-supported, disabilities affecting school-age children: Attention Deficit Hyperactivity Disorder (ADHD) and Developmental Language Disorder (DLD). The dilemma that exists between denying and thereby ignoring difference on the one hand, versus recognising and potentially stigmatising difference on the other, will be explored and the consequences outlined. Our aim is to achieve a middle ground that conceives of diagnosis as a helpful starting point to enable educators to address barriers to access and participation through appropriate adjustments to curriculum, pedagogy and assessment. 相似文献
50.
Joan Scanlon McMath Margaret A. King William Earl Smith 《Early Childhood Education Journal》1998,26(1):19-27
This article discusses the use of nonfiction as a powerful antecedent for success in the types of reading required later on in the intermediate grades. Recent trends in informational (nonfiction) books, values of bringing together young children, and informational books and criteria for selecting high quality informational books are identified. Several question types are highlighted and incorporated into three strategies for bringing together young children, informational books, and questions. Also, a bibliography of high quality informational books is provided. 相似文献