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41.
With 3 years and counting since its inception, the scope and impact of No Child Left Behind is now being felt in classrooms across the nation. Although some successes have been identified, concerns about the implementation and expectations of the legislation are emerging. As a result of the legislation's emphasis on the development of standards and assessment systems in reading, mathematics, and science, educators of other core and elective subjects are weighing the impact of being left out of the No Child Left Behind formula of testing and accountability. In an attempt to ascertain the perceptions and sentiments of social studies teachers concerning the impact of No Child Left Behind and the concomitant issue of state-level testing and accountability policy, a tristate study was conducted. The findings of this research indicate that although elementary, middle, and high school social studies educators recognize the negative consequences of being left out of No Child Left Behind, they are not convinced that being included would be better for them, their students, or social studies education in general. 相似文献
42.
Roel Hendrickx Ester S.B. Ferreira Jaap J. Boon Guylaine Desmarais Dominique Derome Lora Angelova 《文物保护研究》2017,62(7):393-409
Moisture is a driving factor in the long-term mechanical deterioration of canvas paintings, as well as for a number of physico–chemical degradation processes. Since the 1990s a number of publications have addressed the equilibrium hygroscopic uptake and the hygro-mechanical deformation of linen canvas, oil paint, animal glue, and ground paint. In order to visualise and quantify the dynamic behaviour of these materials combined in a painting mock-up or reconstruction, we have performed custom-designed experiments with neutron radiography and nuclear magnetic resonance (NMR) imaging. This paper reports how both techniques were used to obtain spatially and temporally resolved information on moisture content, during alternate exposure to high and low relative humidity, or in contact with liquids of varying water activities. We observed how the canvas, which is the dominant component in terms of volumetric moisture uptake, absorbs and dries rapidly, and, due to its low vapour resistance, allows for vapour transfer towards the ground layer. Moisture desorption was generally found to be faster than absorption. The presence of sizing glue leads to a local increase of moisture content. It was observed that lining a painting with an extra canvas results in a damping effect: i.e. absorption and drying are significantly slowed down. The results obtained by NMR are complementary to neutron radiography in that they allow accurate monitoring of water ingress in contact with a liquid reservoir. Quantitative results are in good agreement with adsorption isotherms. The findings can be used for risk analysis of paintings exposed to changing micro-climates or subjected to conservation treatments using water. Future studies addressing moisture-driven deformation of paintings can make use of the proposed experimental techniques. 相似文献
43.
目的:为了研究高血压大鼠左室流出道电位的变化。方法:利用大鼠的离体心脏,采用常规玻璃微电极细胞内记录方法。观察静息电位(RP)、0相去极幅度(APA)、0相最大除极速度(Vmax)、复极时程(APD)以及复极50%(APD_(50))和复极90%(APD_(90))的时间。结果:高血压大鼠左室流出道诱发电位APD、APD_(50)、APD_(90)都明显高于正常同龄大鼠(P<0.01)。结论:高血压大鼠左室流出道动作电位复极时程延长。 相似文献
44.
W. S. Dakin 《Clearing house (Menasha, Wis.)》2013,86(1):12-14
To a surprising degree, how you communicate determines your effectiveness as a teacher. Relationships are built on communication and easily destroyed by it. (Charles 2000, 48–49) 相似文献
45.
Jamal Abedi 《Educational Measurement》2008,27(3):17-31
High‐stakes decisions for the instruction and assessment of English language learner (ELL) students are made based on the premise that ELL classification is a valid dichotomy that distinguishes between those who are proficient in the use of the English language and those who are not. However, recent research findings draw a vague picture of the term “ELL” and call for a more valid classification system for ELL students. Thus, the purpose of this paper is twofold: (1) to reveal issues concerning the validity of the current ELL classification system based on the results of several empirical studies, and (2) to initiate a discussion on ways to improve the validity of the ELL classification system by proposing a system that uses existing multiple criteria in a stepwise manner. While the suggested system has its own limitations and controversies, we hope this discussion stimulates thoughts and brings much needed attention to this very important national issue. 相似文献
46.
本文在利用遥感解译数据对1990-2010年科尔沁左翼后旗沙地面积变化情况进行分析的基础上,进行沙地面积与人类活动因素、自然因素的相关性分析。结果表明20年来沙地面积总体上呈减少趋势;人类活动因素与沙地面积变化存在负相关性,说明耕地和牲畜数量的增加并未对沙地面积变化造成很大的影响;秋冬季节的最大风速起沙风天数、夏季的最小相对湿度总和、夏秋季节的平均相对湿度总和是沙地面积变化的主要影响因素。基于以上分析,认为科尔沁左翼后旗在治理和利用沙地过程中,固沙植被的选择应当以耐干旱且耗水量较少的草本或沙柳等灌木植被为主;维持现有的禁止放牧、牲畜圈养、禁止砍伐等政策措施以对人类活动进行约束。本研究结果对进一步巩固沙地治理效果、合理利用沙地具有现实意义。 相似文献
47.
缝隙连接蛋白在心肌疾病时的重构及其与运动性心律失常的关系 总被引:1,自引:0,他引:1
顾长海 《天津体育学院学报》2009,24(6):518-521
采用回顾性研究和前瞻性分析相结合的研究方法,综述连接蛋白(Connexins.cxs)的生物学功能及其在不同类型心肌疾病下的变化规律.Cxs在肥厚性心肌病、心肌缺血,左室压力超负荷等心肌疾病时发生重构,力竭运动和大强度运动下诱导的心脏病理改变类似于心肌疾病状态,且运动实践证明力竭运动和大强度运动造成Cxs分布模式改变和表达降低,推测大强度、高负荷运动诱导的心律失常可能与运动诱导心脏Cxs改变有关. 相似文献
48.
Rebecca Zwick Jeffrey C. Sklar Graham Wakefield Cris Hamilton Alex Norman Douglas Folsom 《Educational Measurement》2008,27(2):14-27
In the current No Child Left Behind era, K‐12 teachers and principals are expected to have a sophisticated understanding of standardized test results, use them to improve instruction, and communicate them to others. The goal of our project, funded by the National Science Foundation, was to develop and evaluate three Web‐based instructional modules in educational measurement and statistics to help school personnel acquire the “assessment literacy” required for these roles. Our first module, “What's the Score?” was administered in 2005 to 113 educators who also completed an assessment literacy quiz. Viewing the module had a small but statistically significant positive effect on quiz scores. Our second module, “What Test Scores Do and Don't Tell Us,” administered in 2006 to 104 educators, was even more effective, primarily among teacher education students. In evaluating our third module, “What's the Difference?” we were able to recruit only 33 participants. Although those who saw the module before taking the quiz outperformed those who did not, results were not statistically significant. Now that the research phase is complete, all ITEMS instructional materials are freely available on our Website. 相似文献
49.
50.
探讨耐力训练对心脏结构与功能的影响及其与中国人群CKMM基因A/G多态性之间的关联性.方法:102名中国汉族士兵每周3次5 000m训练,耐力训练前后测定左心室结构与功能相关指标;并应用PCR-RFLP法测定受试者CKMM多态性.结果:训练后安静时ESD、IVS-S、IVS-D、RWT、LVM、LVMI和SV、SVI、EF、FS、T都显著增加(P<0.01);训练后各种负荷时SV、SVI增加,50W时具有显著性;训练后各种负荷时显著性延长T、CO和COI均显著性下降(P<0.01);训练后50W时ESD、ESV、EF和FS变化率在从组和AG组间有显著性差异(P<0.05).结论:耐力训练能使左心结构和心功能呈现良好的顺应性变化,CKMM基因型可能与个体50W负荷时心脏收缩功能对耐力训练的敏感性有关. 相似文献