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In this study, new sponge modified plastic carriers for moving bed biofilm reactor (MBBR) was developed. The performance and membrane fouling behavior of a hybrid MBBR-membrane bioreactor (MBBR-MBR) system were also evaluated. Comparing to the MBBR with plastic carriers (MBBR), the MBBR with sponge modified biocarriers (S-MBBR) showed better effluent quality and enhanced nutrient removal at HRTs of 12h and 6h. Regarding fouling issue of the hybrid systems, soluble microbial products (SMP) of the MBR unit greatly influenced membrane fouling. The sponge modified biocarriers could lower the levels of SMP in mixed liquor and extracellular polymeric substances in activated sludge, thereby mitigating cake layer and pore blocking resistances of the membrane. The reduced SMP and biopolymer clusters in membrane cake layer were also observed. The results demonstrated that the sponge modified biocarriers were capable of improving overall MBBR performance and substantially alleviated membrane fouling of the subsequent MBR unit.

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We compared nucleotide and deduced amino acid sequences of eight Japanese encephalitis virus (JEV) isolates derived from bats in China. We also compared the bat JEV isolates with other JEV isolates available from GenBank to determine their genetic similarity. We found a high genetic homogeneity among the bat JEVs isolated in different geographical areas from various bat species at different time periods. All eight bat JEV isolates belonged to genotype III. The mean evolutionary rate of bat JEV isolates was lower than those of isolates of other origin, but this difference was not statistically significant. Based on these results, we presume that the bat JEV isolates might be evolutionarily conserved. The eight bat JEV isolates were phylogenetically similar to mosquito BN19 and human Liyujie isolates of JEV. These results indicate that bats might be involved in natural cycle of JEV.

Three PAC-DMBRs were developed for wastewater treatment under different PAC dosages with biomass concentrations averaged at 2.5, 3.5 and 5.0g/L. The DMBRs could be continuously operated at 40-100L/mh, while higher fluxes were obtained within the PAC-DMBRs with hydraulic retention times varying in 4-10h. A dose of 1g/L PAC brought about obvious improvement in the sludge particle size distribution, settling, flocculating and dewatering properties due to the formation of biological PAC, and the sludge properties were further improved at a higher PAC dose (3g/L). The addition of PAC notably shortened the DM formation time after air backwashing and enhanced pollutant removal. Moreover, under a long solid retention time (approximately 150d), the concentrations of both soluble and bound extracellular polymeric substances (EPS) decreased substantially because of the adsorption and biodegradation effects of the biological PAC. No obvious impact on biomass activity was observed with PAC addition.

Smoking is associated with attenuated response to inhaled corticosteroids in asthmatics. This offers a rationale for persuasion of smoking cessation. Treatment outcomes might be improved by smoking cessation leading to improved lung function and ameliorated symptoms.