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A fuzzy matter-element model, combined with the entropy weight of an index, has been used as an evaluation method to achieve a comprehensive assessment and analysis of the operational efficiency of wastewater treatment plants (WWTPs). The feasibility of the method had been validated based on actual operational data and instance from eight WWTPs located in a city in Northern China. According to the results of the comprehensive evaluation, the operational efficiency of the WWTP using an anaerobic/anoxic/oxic process was generally better than other wastewater treating technologies. And especially, the removal efficiencies of nitrogen and phosphorus pollutants were much higher for the process, which suits well the actual operational situation of Chinese WWTPs. Total nitrogen (TN) removal rate and the productive quantity of the excess sludge cake were identified as important factors in the evaluation of the operational efficiency for a WWTP. So the operation level of WWTP could be improved by increasing the TN removal rate and decreasing the excess sludge cake quantity. The developed method can evaluate and analyze the operational efficiency scientifically and objectively, and the evaluation results can be used to guide the construction, operation and management of WWTPs in The Three Gorge reservoir district of China. [ABSTRACT FROM AUTHOR]

Quantitative analysis of human behavior and social development is becoming a hot spot of some interdisciplinary studies. A statistical analysis on the population and GDP of 150 cities in China from 1990 to 2013 is conducted. The result indicates the cumulative probability distribution of the populations and that of the GDPs obeying the shifted power law, respectively. In order to understand these characteristics, a generalized Langevin equation describing variation of population is proposed, which is based on the correlations between population and GDP as well as the random fluctuations of the related factors. The equation is transformed into the Fokker-Plank equation to express the evolution of population distribution. The general solution demonstrates a transition of the distribution from the normal Gaussian distribution to a shifted power law, which suggests a critical point of time at which the transition takes place. The shifted power law distribution in the supercritical situation is qualitatively in accordance with the practical result. The distribution of the GDPs is derived from the well-known Cobb-Douglas production function. The result presents a change, in supercritical situation, from a shifted power law to the Gaussian distribution. This is a surprising result-the regional GDP distribution of our world will be the Gaussian distribution one day in the future. The discussions based on the changing trend of economic growth suggest it will be true. Therefore, these theoretical attempts may draw a historical picture of our society in the aspects of population and economy. [ABSTRACT FROM AUTHOR]

Rainfed agriculture is crucial for global food security, with plastic film mulching a widely adopted practice in this domain. However, the impact of plastic film mulching varies significantly across different crop species. This study conducted a comprehensive meta-analysis to evaluate the overall effects of plastic film mulching on the yield, water use efficiency (WUE), and nitrogen partial factor productivity (NPFP) of 13 different crop species. Plastic film mulching significantly enhanced crop yield (26%), WUE (33%), and NPFP (26%) compared to non-mulched conditions. However, the promotional effects varied significantly among different crop species, with noteworthy improvements observed in soybean (44%, 41%, and 45%, respectively) and millet (42%, 57%, and 39%, respectively). For China's major staple crops, plastic film mulching improved the yield, WUE, and NPFP of wheat (29%, 23%, and 27%, respectively), rice (12%, 36%, and 12%, respectively), maize (25%, 29%, and 26%, respectively), and potato (27%, 29%, and 27%, respectively). Regional suitability for plastic film mulching varied among different crops, with rice, maize, soybean, sunflower, linseed, and millet showing increased benefits in cold, semi-arid and arid areas (mean annual temperature (MAT) ≤ 10°C, mean annual precipitation (MAP) < 450 mm, and aridity index (AI) < 0.5). Conversely, peanut and wheat performed better in warm, moist and semi-humid regions (MAT > 10°C, MAP > 450 mm, and AI > 0.5). Moreover, nitrogen fertilizer application influenced the efficacy of plastic film mulching. For soybean, linseed, and millet, the optimal outcome of plastic mulching was observed under low nitrogen application (<110 kg ha–1). For sorghum, sunflower, sweet potato, rice, peanut, potato, and wheat, the optimal outcome of plastic mulching was found under moderate nitrogen application (110–220 kg ha–1). As for maize, cotton, and oilseed rape, the optimal outcome of plastic mulching was observed under high nitrogen application (>220 kg ha–1), but there was no significant difference between moderate and high nitrogen application. A tailored approach considering specific crop requirements and nitrogen application rates is essential for maximizing the benefits of plastic film mulching across diverse local conditions. This study offers valuable insights into optimizing crop productivity under plastic film mulching management systems. [Display omitted] • Plastic film mulching (PFM) enhanced the yield, WUE, and NPFP of all 13 crops. • PFM improved soybean and millet yields the most among the 13 crops. • Most crops exhibited heightened promotional effects under PFM in cold, semi-arid and arid regions. • Peanut and wheat performed better under PFM in warm, moist and semi-humid regions. • Nitrogen fertilizer application can be reduced when using PFM. [ABSTRACT FROM AUTHOR]

Respiratory syncytial virus (RSV) causes respiratory tract infection, particularly acute lower respiratory tract infection (ALRTI), in early childhood. The RSV fusion protein (F protein) is an important surface protein, and it is the target of both cytotoxic T lymphocytes (CTL) and neutralizing antibodies; thus, it may be useful as a candidate for vaccine research. This study investigated the genetic diversity of the RSV F protein. To this end, a total of 1800 nasopharyngeal aspirates from hospitalized children with ALRTI were collected for virus isolation between June 2009 and March 2012. There were 333 RSV-positive cases (277 cases of RSV A, 55 of RSV B, and 1 with both RSV A and RSV B), accounting for 18.5 % of the total cases. Next, 130 clinical strains (107 of RSV A, 23 of RSV B) were selected for F gene sequencing. Phylogenetic analysis revealed that the F gene sequence is highly conserved, with significant amino acid changes at residues 16, 25, 45, 102, 122, 124, 209, and 447. Mutations in human histocompatibility leukocyte antigen (HLA)-restricted CTL epitopes were also observed. Variations in RSV A F protein at the palivizumab binding site 276 (N→S) increased between 2009 and 2012 and became predominant. Western blot analysis and microneutralization data showed a substitution at residue 276 (N→S) in RSV A that did not cause resistance to palivizumab. In conclusion, the RSV F gene is geographically and temporally conserved, but limited genetic variations were still observed. These data could be helpful for the development of vaccines against RSV infection. [ABSTRACT FROM AUTHOR]