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This article provides preliminary validity evidence for the shorter Mandarin version of the Vocabulary Size Test (VST) under the content aspect, technical quality, substantive and generalizability aspect of Messick's (1995) construct validity framework. The shorter version with 177 Chinese university students in three proficiency levels indicates that the test enjoys a high level of validity both from the perspective of classical test theory and item response theory. A one-way ANOVA and detailed statistics of Rasch analyses demonstrate that the test could effectively distinguish learners from different proficiency levels. The first eight levels of the VST generally display an ascending difficulty continuum except that some loan words in the seventh and the eighth level prove to be problematic in assessing Chinese learners' vocabulary size accurately. The generalizability aspect of construct validity is demonstrated in that there is no item bias for learners of the same proficiency group in terms of gender. Compared with the results of other studies either on monolingual or bilingual version, this research attempts to justify the appropriateness of the Mandarin version and calls for cautious applications of the test instrument on Chinese learners.

Urban mining offers an efficient supply of resources because of rich mines and low environmental impacts. Location selection and optimization for urban mining facilities is more complicated than for natural mines, given that it may vary according to the urban population, consumption habits, and economic development. China initiated the National Urban Mining Pilot Bases program in 2010 that targeted 50 national urban mining pilot bases, but unfortunately neglected the location planning issue. Twenty-eight bases have already been selected, which are concentrated in the central and eastern areas of China. This article combines the use of analytic hierarchy process, maximal covering location model, and geographical information systems (GIS) software to optimize locations for China's urban mining pilot bases. Primary findings show that, theoretically, 40 urban mining pilot bases can sufficiently provide maximum gross domestic product (GDP) and population coverage service for China. Taking the current 28 bases as a precondition and 50 bases as the remaining policy target, our second optimization results in a list of 22 cities for the location selection of future urban mining pilot bases. In total, the optimized 22 cities, together with the selected 28 bases, can provide a maximum 97.5% of GDP and 95.1% of population coverage in China. This study illustrates the optimization process for urban mining recycling facilities in general and provides policy advice for China in a specific case. [ABSTRACT FROM AUTHOR]

China's mineral resource consumption has gone through multiple increases since 1980, resulting in the inadequacy of important strategic resources and a high level of external dependence. Some developed countries have already reduced primary resources consumption through urban mining. Can China also break through the bottleneck of the resource shortage and continue its economic and social development through strengthening of urban mining? This article selected copper (Cu), aluminum (Al), lead (Pb), and iron (Fe) as case studies and established predictive models for metal demand, recycling, and stock, based on stock analysis, material flow analysis, and a life distribution model, and then analyzed the metabolism of the four resources and compared the environmental effects of three scenarios. The study indicates that the urban mining potential of Cu, Fe, Al, and Pb will attain 8.1, 711.6, 37.0, and 12.1 million tonnes, respectively, in 2040. Compared with 2010, the substitution rate (secondary metals substituting primary metals) of Cu and Fe increase by 25.4% and 59.9%, whereas external dependence decreases by 30.8% and 25.7%. However, substitution is not obvious regarding Al and Pb. The low resource scenario decreases resources use, which will reduce external dependence in the short term, whereas the strengthened recovery scenario increases resource recovery and has a larger effect in reducing external dependence in the long term. So, in line with urban mining in the future, China should change its environment and resource strategy, further strengthen layout and construction of urban mining demonstration bases, and encourage the use of recyclable resources to provide a better foundation for urban mining. [ABSTRACT FROM AUTHOR]

In order to evaluate the prevalence of childhood asthma, allergic diseases and pneumonia in Urumqi City, China, as well as its associations with housing and home characteristics, a cross-sectional study was performed in 4618 children (81.7% response rate, average age 4.7±0.9 year, boys accounting for 53.7%). Questions on children’s asthma and allergic diseases were from the International Study on Asthma and Allergies in Childhood (ISAAC) and were integrated with questions on the home environment from the Dampness in Buildings and Health (DBH) study, slightly modified to account for Chinese building characteristics and life habits. The prevalences of physician diagnosed asthma, allergic rhinitis (AR) and pneumonia were 3.6%, 8.7% and 40.9%, respectively. One fourth of children reported wheezing and more than 40% AR symptoms in the last 12 months. Controlling for confounding factors, positive associations were found for home mold/dampness and wheezing (adjusted odds ratio, aOR 1.33, 95% CI 1.07–1.66), AR symptoms (1.34, 1.09–1.64) last 12 months and physician diagnosed pneumonia (1.33, 1.09–1.62). Floor material by wood, PVC or carpeting; and walls by wallpaper, painting or wood material, were positively associated with AR symptoms. Home environmental tobacco smoke (ETS) was positively associated with wheezing (1.23, 1.04–1.46) and pneumonia (1.25, 1.07–1.45). In conclusion, there was a relatively high prevalence of asthmatic and AR symptoms and diagnosed pneumonia in preschool children in Urumqi. Home signs of mold growth or dampness, windowpane condensation, as well as ETS and interior surface materials emitting chemicals were risk factors for allergic symptoms and pneumonia. [ABSTRACT FROM AUTHOR]

High delicate particulate matter (PM 2.5 ) concentration can seriously reduce air quality, destroy the environment, and even jeopardize human health. Accordingly, accurate prediction for PM 2.5 plays a vital role in taking precautions against upcoming air ambient pollution incidents. However, due to the disturbance of seasonal and nonlinear characteristics in the raw series, pronounced forecasts are confronted with tremendous handicaps, even though for seasonal grey prediction models in the preceding researches. A novel seasonal nonlinear grey model is initially designed to address such issues by integrating the seasonal adjustment factor, the conventional Weibull Bernoulli grey model, and the cultural algorithm, simultaneously depicting the seasonality and nonlinearity of the original data. Experimental results from PM 2.5 forecasting of four major cities (Shanghai, Nanjing, Hangzhou, and Hefei) in the YRD validate that the proposed model can obtain more accurate predictive results and stronger robustness, in comparison with grey prediction models (SNGBM(1,1) and SGM(1,1)), conventional econometric technology (SARIMA), and machine learning methods (LSSVM and BPNN) by employing accuracy levels. Finally, the future PM 2.5 concentration is forecasted from 2020 to 2022 using the proposed model, which provides early warning information for policy-makers to develop PM 2.5 alleviation strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The objectives of this study were to understand the characteristics of heavy metal pollution caused by mining activities on the two sides of the Shun'an river and the response of soil microorganisms to the habitats by different contamination levels and vegetation. This paper selected soil samples from the banks of the Shun'an River near the Shizishan mining area, which is at the left of the river, in Tongling, Anhui Province, China. Using Illumina MiSeq 2500 technology, we analyzed the relationship between environmental factors and microbial communities. As the distance from the mining area increased, the heavy metal comprehensive pollution and potential risk value decreased. Additionally, the pollution severity and risk value of the left bank, where the mining area lies, were generally higher than those of the right bank. Because the symmetric sampling points on both banks of the river had similar planting types, their environmental factors and microbial community structure were similar and clustered. However, under different vegetation, the paddy soils tended to have a higher nutrient content and community richness and diversity than the vegetable fields or the abandoned land. It was found that soil microbial communities in this area were mostly affected by pH and Nemerow pollution index (P N ). The pH significantly affected the abundance and structure of most microorganisms. In addition, Proteobacteria, Acidobacteria, and Bacteroidetes had significant tolerance to Zn, Pb, and Cd. By exploring the potential use of these tolerant microorganisms, we seek to provide strains and the theoretical basis for the bioremediation of areas contaminated by heavy metal.