Poisoning the mind: Arsenic contamination of drinking water wells and children's educational achievement in rural Bangladesh

Bangladesh has experienced the largest mass poisoning of a population in history owing to contamination of groundwater with naturally occurring inorganic arsenic. Prolonged drinking of such water risks development of diseases and therefore has implications for children's cognitive and psychological development. This study examines the effect of arsenic contamination of tubewells, the primary source of drinking water at home, on the learning outcome of school-going children in rural Bangladesh using recent nationally representative data on secondary school children. We unambiguously find a negative and statistically significant correlation between mathematics scores and arsenic-contaminated drinking tubewells at home, net of the child's socio-economic status, parental background and school specific unobserved correlates of learning. Similar correlations are found for an alternative measure of student achievement and subjective well-being (i.e. self-reported measure of life satisfaction), of the student. We conclude by discussing the policy implication of our findings in the context of the current debate over the adverse effect of arsenic poisoning on children.     

The quality vs. the quantity of schooling: What drives economic growth?

This paper challenges Hanushek and Woessmann's (2008) contention that the quality and not the quantity of schooling determines a nation's rate of economic growth. I first show that their statistical analysis is flawed. I then show that when a nation's average test scores and average schooling attainment are included in a national income model, both measures explain income differences, but schooling attainment has greater statistical significance. The high correlation between a nation's average schooling attainment, cumulative investment in schooling, and average tests scores indicates that average schooling attainment implicitly measures the quality as well as the quantity of schooling.     

Economic returns to education: What We Know, What We Don’t Know, and Where We Are Going—Some brief pointers

The estimation of the economic return to education has perhaps been one of the predominant areas of analysis in applied economics for over 50 years. In this short note we consider some of the recent directions taken by the literature, and also some of the blockages faced by both science and policymakers in pushing forward some key issues. This serves by way of introduction to a set of papers for a special issue of the Economics of Education Review.     

The impact of child labor on schooling outcomes in Nicaragua

Child labor is considered a key obstacle to reaching the international commitments of Education For All. However, the empirical evidence on the effects of child labor on educational attainments is mostly limited to static measurements. This paper assesses the consequences of child labor on schooling outcomes over time by employing a three-year longitudinal household data set from Nicaragua. The potential endogeneity of past child labor and school outcomes is addressed through instrumental variables. The time a child dedicates to work is found to have harmful consequences on subsequent educational achievements, even after controlling for previous human capital accumulation and other factors. In particular, working over three hours a day is associated with school failure in the medium term. A distinction by type of work shows that time spent in market production has larger negative effects on school outcomes than time spent performing household chores.     

有氧运动对KK-Ay小鼠骨骼肌p38 MAPK、血清TNF-α及FFA的影响

目的:从p38 MAPK信号转导通路的角度探讨运动降低糖尿病血糖水平的机制,为运动治疗糖尿病提供科学依据和参考。研究方法:雄性6月龄KK-Ay和C57BL/6J小鼠各12只,按血糖配对后随机分为糖尿病运动组(KE组)和糖尿病对照组(KC组);正常运动组(CE组)和正常对照组(CC组)。进行坡度0°,速度12 m/min,时间30 min的跑台运动后,实验检测p38蛋白表达和磷酸化,测定血糖浓度、血清胰岛素和TNF-α、FFA。研究结果:KK-Ay小鼠血糖高于C57BL/6J小鼠,KE组和CE组血糖分别较实验前下降了34%和25%;运动后CE组血清胰岛素浓度比CC组低55%,KE组则较KC组低43%;骨骼肌p38磷酸化水平KC组高于CC组,CE组高于C组,KE组高于KC组;血清TNF-α及FFA浓度KC组明显高于CC组,KE组明显低于KC组。结论:一次性有氧运动可以有效降低KK-Ay小鼠的血糖及血清胰岛素水平,直接激活KK-Ay小鼠骨骼肌p38磷酸化,降低血清TNF-α和FFA水平,并通过p38间接作用于TNF-α、FFA,最终达到降低血糖的效果,这可能是运动降血糖的部分分子机制。     

前躯体煅烧法制备Cr2O3微/纳米球

采用前躯体煅烧法制备了无机微/纳米材料Cr2O3.利用有机碱的缓慢水解,用无机盐铬源,在水和乙醇或者其他混合溶剂中进行水热反应,首先制得前躯体Cr（OH）3,然后通过煅烧得到Cr2O3微/纳米粒子.通过对比实验,发现影响前躯体和最终产物尺寸大小的主要因素是所使用的有机碱（沉淀剂）的种类.对前躯体采用红外光谱（IR）和热重分析（TG）进行了表征,对产物采用X-射线粉末衍射（XRD）、扫描电镜（SEM）和透射电镜（TEM）进行了表征.     

Changes to university IPR regulations in Europe and the impact on academic patenting

This article develops a general framework to describe the changes in university IPR regulations in Europe and their effects on the patenting activities of universities and on knowledge transfer processes. Understanding the effects of changes in IPR regulations on academic patenting is a complex issue, and parallels with the US case can be misleading. First, despite the general trend towards institutional ownership, university IPR regulations in Europe remain extremely differentiated and there is no one-to-one mapping to the US system. Second, it is difficult to disentangle the quantitative and qualitative effects of changes in IPR ownership regulations on academic patenting activities from the effects of concurrent transformations in the institutional, cultural and organizational landscape surrounding academic knowledge transfer. The article proposes a review and typological classification of national university IPR ownership systems on the basis of their development since 2000, and uses it to analyze the aggregate dynamics of academic patent ownership in several European countries. The analysis of patterns of ownership of academic patents shows that there has been a general increase in university patenting since 1990, with a significant slowdown (and even reduction in some countries) after early 2000s accompanied by a switch in academic patents ownership in favor of university ownership though preserving the European specificity of high company ownership of academic invented patents.     

生物合成Cr2O3纳米颗粒

微生物还原固定铬对Cr（VI）污染环境修复具有重要意义。筛选获得一株Cr（VI）还原菌株XMCr-6,并对其生物还原固定Cr（VI）进行了研究。动力学实验显示Cr（VI）是先还原,然后吸附固定在细胞表面。XPS分析表明铬在细胞表面主要是以三价的形式存在,高分辨透射电镜结合能谱分析进一步证实是形成Cr2O3纳米颗粒。