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101.
102.
This paper investigates the relationship between non-parental care and toddlers’ behavioral outcomes using data from Australia. In particular, we explore heterogeneity in the relationship using the unique data on quality attributes: carer/child ratio, share of qualified staff, and expert ratings. The results suggest that full-time non-parental care, particularly center care, is negatively associated with toddlers’ behavioral outcomes. The negative association is however mitigated when centers have a larger number of carers per child. The negative association between non-parental care and behavioral outcomes also appears to be larger for children with better-educated parents.  相似文献   
103.
This study estimates the value of the private and public benefits that accrue to Minnesota residents from state government subsidies to higher education. In 2005, the University of Minnesota and the Minnesota State Colleges and Universities system received $832 million from Minnesota's state government to support educational programs. These subsidies allow these institutions to offer lower tuition rates, increasing the number of Minnesotans with bachelor and graduate degrees. We calculate that removing these subsidies would eventually lead to 14,000 fewer graduate degree holders in Minnesota, and reduce those with bachelor's degrees or “some college” by 42,000. The annual economic cost of these subsidies is about $326 million; this is less than annual state appropriations because most of those appropriations are income transfers from taxpayers to students, not an economic cost. We estimate that the annual value of the benefits of these subsidies is between $531 and $786 million ($381 and $570 million) when a 3% (5%) discount rate is used. We also discuss some of the income distribution consequences.  相似文献   
104.
This study examines the impact that collective bargaining has on multiple dimensions of teacher compensation, including average and starting salaries, early and late returns to experience, returns to graduate degrees, and the incidence of different pay for performance schemes. Using data from the School and Staffing Survey (SASS) and a more recent data set, the Teacher Rules, Roles and Rights (TR3), we find that collective bargaining has a significant impact on all aspects of current, qualification-specific salary schedules. Further, we find some evidence that bargaining impacts the design of performance pay plans. Specifically, unions tend to encourage teacher bonuses that are based on additional qualifications or duties, but discourage bonuses that directly reward improved student test scores.  相似文献   
105.
Using a survey of a cohort of UK graduates, linked to administrative data on higher education participation, this paper investigates the labour market attainment of recent graduates by subject of study. We document a large heterogeneity in the mean wages of graduates from different subjects and a considerably larger one within subject with individuals with the most favourable unobserved characteristics obtaining wages almost twice as large as those with the worst. Moreover, gender differences in wages within subjects are also large. We then simulate a graduate tax to calculate a willingness to pay – in form of tuition fees – to capture these subject wage premia.  相似文献   
106.
21世纪的今天,人们面对社会上五花八门的现代健身养生项目,如何选择已成为追求自我身心健康的人们较为关注的问题。文章就这一问题为大家解析健身养生项目的基本特征、健身功效所在,并在揭开健身养生理论神秘面纱的同时,使人们进一步了解现代武术健身养生常见的锻炼项目。旨在让大家轻松地找到一种具有实效性的现代武术健身养生项目为己用,从而达到提高自我健康的目的。  相似文献   
107.
外源性生长激素对运动大鼠骨骼肌形态和代谢机能的影响   总被引:1,自引:0,他引:1  
目的:旨在观察生长激素对运动大鼠骨骼肌形态及机能的影响。方法:28只雄性成熟SD大鼠在适应性训练后随机分成安静对照组、安静注射组、运动对照组和运动注射组。运动组和运动注射组进行跑台训练8周。皮下注射rhGH。结果:1)注射生长激素后,出现了肌纤维排列松散,细胞核数量减少且体积变小,骨骼肌细胞间质水肿等现象。2)在8周的训练后,肌纤维横截面积稍有下降,但变化不明显。注射生长激素4周后,安静组和运动组均显著增加,且安静注射组大鼠的肌纤维横截面积显著高于运动注射组。3)运动组及运动注射组骨骼肌IGF-I明显升高。安静注射组及运动注射组血清IGF-I明显升高,运动组无明显变化。4)各组肌肉总蛋白含量有所增加,分别为安静注射组升高4.77%、运动组升高31.13%、运动注射组升高28.06%。5)运动组及运动注射组腓肠肌ATP酶活性升高。结论:1)8周耐力运动明显促进大鼠骨骼肌蛋白质合成,同时增加了骨骼肌IGF-I水平。2)外源性rhGH注射4周后,大鼠骨骼肌细胞形态产生肥大,骨骼肌肌纤维横截面积明显增加。3)外源性rhGH注射4周可以显著提高血清和骨骼肌IGF-I水平,且骨骼肌总蛋白的含量变化与骨骼肌IGF-I的变化趋势平行。4)外源性rhGH注射4周可以对肌纤维类型及分配产生调节作用,从而改变肌肉代谢酶活性。  相似文献   
108.
实时虚拟参考咨询服务在图书馆服务中发挥着积极且重要的作用。清华大学图书馆基于开源软件A.L.I.C.E.开发出实时智能聊天机器人"小图",提供参考咨询、图书搜索、自我学习等多种服务,并将其推广至社交网络,取得良好的效果。  相似文献   
109.
文章介绍了服务器虚拟化技术和VMware Infrastructure3虚拟架构套件,详细阐述了VMware服务器虚拟化技术在中央民族大学数字图书馆中的应用,结果表明虚拟化后的服务器是稳定和高效的。  相似文献   
110.
In this paper, we utilize transmission-line matrix simulations to study the electromagnetic properties of hyperbolic metamaterial grids, which are synthesized by arranging unloaded transmission lines over electrical ground planes, such that the unit cells are rectangular in shape. The hyperbolic grids support Bragg and Hyperbolic resonant modes that have rectangular and hyperbolic dispersion surfaces, respectively. We demonstrate the formation of these resonant modes in the hyperbolic grids and their refraction, and spatial scanning properties via circuit simulations. The simulation results are compared with experimental results of a two-layer anisotropic hyperbolic metamaterial.  相似文献   
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