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排序方式: 共有195条查询结果,搜索用时 15 毫秒
61.
Booney Vance Larry Mayes Ronald C. Eaves Naim Abu Homos 《Psychology in the schools》1991,28(2):100-105
The present investigation compared the Cognitive Levels Test (CLT) and the Wechsler Intelligence Scale for Children-Revised (WISC-R) scores for 55 children who were referred for remedial educational services. A comparison of the correlations for each of the criterion measures from the WISC-R showed a consistent significant positive relationship with the CLT. A repeated measures analysis of variance that compared standard scores for the CLT with those of the WISC-R indicated that significant differences existed between WISC-R IQs and the CLT Cognitive Index. Implications concerning the validity of the Cognitive Levels Test are discussed. 相似文献
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Hudson W. T. Hoyt W. M. Cook D. M. Cason F. L. Hillyard L. R. 《Education, IRE Transactions on》1959,2(1):10-13
Each year America's industries and colleges join forces in an action aimed at converting the engineering student into an engineer employee. Principals in this operation are the company recruiter and the college placement director. Through the years each member of this unique alliance has come to learn the strength and weaknesses of his partner; each has profited and suffered through the other; each has developed his own ideas on how the other should operate. IRE TRANSACTIONS ON EDUCATION recently asked a number of executives on company recruiting staffs and college placement offices for their opinions on the current state of college recruiting, and for suggestions on improving the operation in future years. This two-part article presents excerpts from some of the replies received. 相似文献
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C. G. Hebert S. J. R. Staton T. Q. Hudson S. J. Hart C. Lopez-Mariscal A. Terray 《Biomicrofluidics》2015,9(2)
The ability to confine flows and focus particle streams has become an integral component of the design of microfluidic systems for the analysis of a wide range of samples. Presented here is the implementation of a 3D microfluidic nozzle capable of both focusing particles as well as dynamically positioning those particles in selected flow lamina within the downstream analysis channel. Through the independent adjustment of the three sheath inlet flows, the nozzle controlled the size of a focused stream for 6, 10, and 15 μm polystyrene microparticles. Additional flow adjustment allowed the nozzle to dynamically position the focused particle stream to a specific area within the downstream channel. This unique ability provides additional capability and sample flexibility to the system. In order to gain insight into the fluidic behavior of the system, experimental conditions and results were duplicated within 4.75 μm using a COMSOL Multiphysics® model to elucidate the structure, direction, proportion, and fate of fluid lamina throughout the nozzle region. The COMSOL Multiphysics model showed that the position and distribution of particles upon entering the nozzle have negligible influence over its focusing ability, extending the experimental results into a wider range of particle sizes and system flow rates. These results are promising for the application of this design to allow for a relatively simple, fast, fully fluidically controlled nozzle for selective particle focusing and positioning for further particle analysis and sorting. 相似文献
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Objective:There are no existing validated search filters for the group of 37 Organisation for Economic Co-operation and Development (OECD) countries. This study describes how information specialists from the United Kingdom''s National Institute for Health and Care Excellence (NICE) developed and evaluated novel OECD countries’ geographic search filters for MEDLINE and Embase (Ovid) to improve literature search effectiveness for evidence about OECD countries.Methods:We created the draft filters using an alternative approach to standard filter construction. They are composed entirely of geographic subject headings and are designed to retain OECD country evidence by excluding non-OECD country evidence using the NOT Boolean operator. To evaluate the draft filters’ effectiveness, we used MEDLINE and Embase literature searches for three NICE guidelines that retrieved >5,000 search results. A 10% sample of the excluded references was screened to check that OECD country evidence was not inadvertently excluded.Results:The draft MEDLINE filter reduced results for each NICE guideline by 9.5% to 12.9%. In Embase, search results were reduced by 10.7% to 14%. Of the sample references, 7 of 910 (0.8%) were excluded inadvertently. These references were from a guideline about looked-after minors that concerns both OECD and non-OECD countries.Conclusion:The draft filters look promising—they reduced search result volumes while retaining most OECD country evidence from MEDLINE and Embase. However, we advise caution when using them in topics about both non-OECD and OECD countries. We have created final versions of the search filters and will validate them in a future study. 相似文献
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