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Collected ratings of communication ease and of engagement for 95 deaf junior and senior high school students (aged 12–21 yrs) in a large, urban, multiethnic school for the deaf. Ratings were made by the students' English teachers and by the students themselves. High teacher ratings for communication ease and engagement were associated with high academic achievement as measured by the Stanford Achievement Test. High student ratings for communication ease were also associated with academic achievement. The 2 best predictors of academic achievement were student-rated communication ease and teacher-rated engagement. Findings suggest that it is important for teachers to be sensitive to the level of communication comfort of their students because students who enjoy easier communication may be more likely to be engaged, or more actively involved, in classroom learning and to demonstrate higher academic achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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LM Powell DT Dryden DF Willcock RH Pain NE Murray 《Canadian Metallurgical Quarterly》1993,234(1):60-71
The methyltransferase of the EcoK type I restriction/modification system is trimeric, M2S1, where the S subunit determines the sequence specificity of the enzyme. The methyltransferase has a strong preference for hemimethylated substrate DNA and, therefore, we have investigated the effect of the methylation state of DNA on binding by the enzyme, together with the effects on binding of the cofactor S-adenosyl-L-methionine. Our results indicate that the methyltransferase has two non-interacting S-adenosyl-L-methionine binding sites, each with a dissociation constant of 3.60 (+/- 0.42) microM determined by equilibrium dialysis, or 2.21 (+/- 0.29) microM determined by the displacement of a fluorescent probe. Ultraviolet light-induced crosslinking showed that S-adenosyl-L-methionine binds strongly only to the modification (M) subunits. Changes in the sedimentation velocity of the methyltransferase imply a protein conformational change due to S-adenosyl-L-methionine binding. Gel retardation results show that the binding of S-adenosyl-L-methionine to the methyltransferase enhances binding to both specific and non-specific DNAs, but the enhancement is greater for the specific DNA. Differences in binding affinities contribute to the recognition of the specific nucleotide sequence AAC(N)6GTGC by the methyltransferase in preference to a non-specific sequence. In contrast, although the complexes of unmodified and hemimethylated DNAs with the methyltransferase have different mobilities in non-denaturing gels, there appears to be no contribution of binding affinity to the distinction between these two substrates. Therefore, the preference for a hemimethylated substrate must be due to a difference in catalysis. 相似文献
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通过工程地质调查、室内围岩物化分析和力学试验 ,深入研究了围岩变形力学机制和破坏机理 .根据新奥法施工原理 ,采取了有针对性的综合治理措施 ,将围岩复杂的变形力学机制转化为单一的变形力学机制 ,使该工程得到了有效治理 .取得的技术经验推广应用于该矿井其它失稳破坏工程 ,均获得了圆满成功 相似文献
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龙秀兰 《石油化工设备技术》2003,24(2):11-13
阐述了全渣油催化裂化装置反应器中旋流快分系统(VQS)的工作原理,对其受力情况进行了分析。较详细介绍了放流快分系统的支撑结构形式,并就支撑梁(焊接工字钢)的选材、几何尺寸进行了详细的分析与比较。 相似文献
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The electromagnetic properties of electrically thick rectangular microstrip antennas were investigated experimentally. Antennas were fabricated with different patch sizes and with electrical thicknesses ranging from 0.03 to 0.23 wavelengths in the dielectric substrate. The resonant frequencies were measured and compared to existing formulas. The bandwidth was calculated as a function of electrical thickness and the antenna radiation patterns were measured. 相似文献