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The groundwater system in the strata within 800 m of Dezhou city, which is located in the North China Plain (NCP), China, includes four aquifer groups (labeled AgI to AgIV from top to bottom). The exploitation of deep groundwater from AgIII and AgIV is generally considered the primary reason for land subsidence in Dezhou. Although the deep groundwater exploitation volume has decreased significantly, the annual land subsidence has been accelerating in the central area of Dezhou since 2012. The factors resulting in the acceleration of land subsidence are discussed. Presently, AgII and AgIII between 60 and 500 m below the ground surface are the two main layers contributing to land subsidence, the settlement of which accounted for 74% of the total subsidence value. The increasing settlement of AgIII may be due to the soil creep caused by the continuous release of groundwater from AgIII. AgII is characterized by high compressibility, the deformation of which is susceptible to a decrease in the groundwater level. Since AgII is not the historical groundwater exploitation layer, the decrease in the groundwater level of AgII may be caused by the downward leaking recharge to AgIII and lateral recharge to the surrounding cities in the NCP. The study of the deformation mechanism of AgII is essential for subsidence control in Dezhou. Geological investigation and groundwater-level monitoring of AgII and joint control of regional groundwater overexploitation in the NCP should be strengthened. [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]

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]