Can Social-Emotional Learning Reduce School Dropout in Developing Countries?

An alarming number of students drop out of junior high school in developing countries. In this study, we examine the impacts of providing a social-emotional learning (SEL) program on the dropout behavior and learning anxiety of students in the first two years of junior high. We do so by analyzing data from a randomized controlled trial involving 70 junior high schools and 7,495 students in rural China. After eight months, the SEL program reduces dropout by 1.6 percentage points and decreases learning anxiety by 2.3 percentage points. Effects are no longer statistically different from zero after 15 months, perhaps due to decreasing student interest in the program. However, we do find that the program reduces dropout among students at high risk of dropping out (older students and students with friends who have already dropped out), both after eight and 15 months of exposure to the SEL program. (C) 2016 by the Association for Public Policy Analysis and Management

Red mud (RM)-Induced enhancement of iron plaque formation reduces arsenic and metal accumulation in two wetland plant species

Human activities have resulted in arsenic (As) and heavy metals accumulation in paddy soils in China. Phytoremediation has been suggested as an effective and low-cost method to clean up contaminated soils. A combined soil-sand pot experiment was conducted to investigate the influence of red mud (RM) supply on iron plaque formation and As and heavy metal accumulation in two wetland plant species (Cyperus alternifolius Rottb., Echinodorus amazonicus Rataj), using As and heavy metals polluted paddy soil combined with three rates of RM application (0, 2%, 5%). The results showed that RM supply significantly decreased As and heavy metals accumulation in shoots of the two plants due to the decrease of As and heavy metal availability and the enhancement of the formation of iron plaque on the root surface and in the rhizosphere. Both wetland plants supplied with RM tended to have more Fe plaque, higher As and heavy metals on roots and in their rhizospheres, and were more tolerant of As and heavy metal toxicity. The results suggest that RM-induced enhancement of the formation of iron plaque on the root surface and in the rhizosphere of wetland plants may be significant for remediation of soils contaminated with As and heavy metals

京津冀地区不同水资源配置方式的影响比较——基于社会核算矩阵

为了缓解京津冀地区水资源短缺状况,政府试图改变三地分散配置水资源的原有模式,建立京津冀水资源统一配置平台。通过编制基于水生产和供应业的京津冀细化社会核算矩阵,并利用乘数分解和结构化路径分析方法,揭示并比较了京津冀2种水资源配置模式下水生产供应部门变动对其他部门的经济影响和具体的作用路径。研究表明,统一配置后北京水生产供应业的带动作用下降,但注入资金在经济体系中的循环比重增加;天津、河北水生产供应业的带动作用上升,生产部门之间的直接联系增强,同时天津居民资本收入的比重提升。总体上,采取统一配置模式对京津冀产业联系有积极影响,因此建议京津冀地区建立和完善跨区域的水资源配置机制,统筹各类水源,推进京津冀协同发展

Precipitation Spectra Analysis Over China With High-Resolution Measurements From Optimally-Merged Satellite/Gauge Observations-Part II: Diurnal Variability Analysis

Timing and diurnal variation of summer precipitation is analyzed over China using a new high-resolution (0.1 degrees, hourly) satellite-gauge merged surface rainfall dataset that spans from 2008 through 2013. The results show that: 1) both precipitation amount (PA) and frequency (PF) show strong diurnal cycles with local solar time (LST); 2) peak times of PA (PAPT) primarily occur from 15 LST to 00 LST in most parts of the Tibet Plateau (TP), Xinjiang (XJ), Northwestern China (NW), Northeastern China (NE), and Southern China (SC), and the PAPT occurs from 00 LST to 09 LST in southern TP, Eastern XJ, western NW, southern NE, eastern Northern China (NC), and most parts of Southwestern China (SW); 3) the PAPT transitions eastward with time, occurring at similar to 15 LST in central TP, at midnight in SW, and at 15-18 LST in the eastern coastal regions that are in the lower reach of Yangtze River and in the north side of Wuyi Mountains; 4) peak times of PF (PFPT) show a similar spatial pattern with PAPT, but with a small temporal (1-2 h) lead; 5) peak times of precipitation intensity (PIPT) occur during the 18-00 LST time frame in the southeastern TP and central SW regions. The PIPT along the upper Yangtze River valley occurs around 00-06 LST. The PIPT occurs in the morning at around 06-09 LST in the mid-lower Yangtze River valley and most parts of SC. This study on the diurnal cycle of precipitation over China can be used as a reference to validate atmospheric and hydrologic models, and also to guide hydrometerological research and applications

地理元胞自动机模型研究进展

元胞自动机(Cellular Automata,简称CA)是一种基于微观个体的相互作用空间离散动态模型,其强大的计算功能、固有的平行计算能力、高度动态及空间概念等特征,使它在模拟空间复杂系统的时空动态演变研究具有较强的优势。文章回顾了元胞自动机的发展历程,阐述了CA在地理学中的主要应用领域和研究进展,在此基础上,以现实世界地理实体及现代城市扩张特征为视角,分析目前CA研究所面临的问题,并对其未来的研究趋势进行了初步探讨,认为以下3个方面将是未来CA研究的热点:1利用不规则元胞及可控邻域的CA模型,对不同规则或不同邻域地理实体的模拟研究;2采用三维元胞自动机对现代城市扩张进行立体化模拟,以克服二维CA模型的缺陷;3将矢量元胞自动机模型应用于地理实体的模拟研究,进一步提高模拟精度

中部三省多尺度城镇用地扩张分异规律

多尺度城镇用地扩张综合特征度量,是深刻揭示城镇用地扩张过程及驱动,促进可持续城镇用地扩张管控的重要基础。研究分析了1990—2015年期间湖北、湖南和江西三省不同尺度县域城镇用地扩张自由度、蔓延度和感观优劣度及其分异规律,结果表明:(1)区域尺度城镇用地扩张自由度总体较低,但蔓延度较高;湖北、江西省扩张整体扩张局势较好;非城市群地区具有比城市群地区更小的扩张自由度和蔓延度,以及更高的感观优劣度,感官优劣度呈负值的城市仅24个;中部三省大部分地区地级市尺度自由度、蔓延度和感观优劣度良好;(2)不同尺度各城市城镇用地扩张自由度、蔓延度和感观优劣度存在差异;(3)中部三省城镇用地扩张呈稳定增长、持续蔓延和复合扩张模式

High-resolution simulation of the spatial pattern of water use in continental China

High-resolution data on the spatial pattern of water use are a prerequisite for appropriate and sustainable water management. Based on one well-validated hydrological model, the Distributed Time Variant Gains Model (DTVGM), this paper obtains reliable high-resolution spatial patterns of irrigation, industrial and domestic water use in continental China. During the validation periods, ranges of correlation coefficient (R) and Nash-Sutcliffe efficiency (NSE) coefficient are 0.67-0.96 and 0.51-0.84, respectively, between the observed and simulated streamflow of six hydrological stations, indicating model applicability to simulate the distribution of water use. The simulated water use quantities have relative errors (RE) less than 5% compared with the observed. In addition, the changes in streamflow discharge were also correctly simulated by our model, such as the Zhangjiafen station in the Hai River basin with a dramatic decrease in streamflow, and the Makou station in the Pearl River basin with no significant changes. These changes are combined results of basin available water resources and water use. The obtained high-resolution spatial pattern of water use could decrease uncertainty of hydrological simulation and guide water management efficiently

Effect of urea fertilization on biomass yield, chemical composition, in vitro rumen digestibility and fermentation characteristics of straw of highland barley planted in Tibet

A completely randomized experiment for planting highland barley in 36 field plots of the Lhasa Agricultural Experiment Station was applied to investigate the effect of urea nitrogen (N) fertilization levels of 0 (control), 156, 258, 363, 465 and 570 kg/ha on nutrient accumulation, in vitro rumen gas production and fermentation characteristics of highland barley straw (HBS). Each urea application was divided into three portions of 0.4, 0.3 and 0.3 and sequentially fertilized at seeding (growth stage (GS) 0), stem elongation (GS 32) and heading (GS 49), respectively. The maturity stage lasted 5-13 days longer in response to the urea N fertilization compared with the control. After removing grains, HBS biomass was harvested at maturity. The biomass yields of leaf, stem, straw and grain were increased quadratically with increasing urea N fertilization, and HBS and grain yields peaked at the estimated urea N fertilization levels of 385 and 428 kg/ha, respectively. The increase of urea N fertilization increased the accumulation of crude protein, cellulose and lignin, and decreased the content of ash and hemicellulose in HBS, resulting in a decrease of the energy content available to be metabolized. After incubating HBS for 72 h with rumen fluids from lactating cows, the urea N fertilization decreased in vitro dry matter disappearance and cumulative gas production, and slightly altered fermentation end-gas composition. Urea N fertilization decreased microbial volatile fatty acid production, but did not alter the ratio of lipogenic acetate and butyrate to glucogenic propionate. In a brief, the current urea N fertilization strategy promoted the growth of the highland barley and increased biomass yield, protein and cellulose accumulation of HBS. A urea N fertilization level. 385 kg/ha could be sufficient for growth of highland barley in Tibet without a consequent nutritive reduction in ruminal digestion