(1) Background: is an important zoonotic pathogen that infects pigs and can occasionally cause life-threatening systemic infections in humans. Two large-scale outbreaks of streptococcal toxic shock-like syndrome in China suggest that the pathogenicity of has been changing in recent years. Genetic analysis revealed the presence of a chromosomal pathogenicity island (PAI) designated SsPI-1 in Chinese epidemic strains.
View Article and Find Full Text PDFNatural attenuation is an effective and feasible technology for controlling groundwater contamination. This study investigated the potential effectiveness and mechanisms of natural attenuation of 1,1,1-trichloroethane (TCA) contaminants in shallow groundwater in Shanghai by using a column simulation experiment, reactive transport model, and 16S rRNA gene clone library. The results indicated that the majority of the contaminant mass was present at 2-6 m in depth, the contaminated area was approximately 1000 m × 1000 m, and natural attenuation processes were occurring at the site.
View Article and Find Full Text PDFSorption and desorption play an important role in the transport and the fate of tetrachloroethylene (PCE) in soil. In order to examine influences of different soil compositions on PCE sorption-desorption, equilibrium batch experiments were carried out using four sorbents (natural soil with 2.23% total organic carbon (TOC), H2O2-treated soil, 375 degrees C-treated soil and 600 degrees C-treated soil) with different initial PCE liquid concentrations (c0).
View Article and Find Full Text PDFThe occurrence and removal of six pharmaceuticals and personal care products (PPCPs) including caffeine (CF), N, N-diethyl-meta-toluamide (DEET), carbamazepine, metoprolol, trimethoprim (TMP), and sulpiride in a municipal wastewater treatment plant (WWTP) in Shanghai, China were studied in January 2013; besides, grab samples of the influent were also taken every 6 h, to investigate the daily fluctuation of the wastewater influent. The results showed the concentrations of the investigated PPCPs ranged from 17 to 11,400 ng/L in the WWTP. A low variability of the PPCP concentrations in the wastewater influent throughout the day was observed, with the relative standard deviations less than 25 % for most samples.
View Article and Find Full Text PDFThis study investigated the effects of PCE and 2-CP co-contamination on growth of microbial community in terms of enzymatic activity and microbial diversity in activated sludge. Results showed that the activities of three key enzymes (dehydrogenase, phosphatase and urease) decreased significantly when PCE (in the range of 5-150 mg/L) was mixed with 2-CP (in the range of 25-150 mg/L). Especially, activity of dehydrogenase decreased by more than 93% as the concentration of PCE and 2-CP both reached 150 mg/L.
View Article and Find Full Text PDFAdsorption plays an important role in the transport and the fate of trichloroethylene (TCE) in soil. Six types of soil, including two types of natural soil with different organic carbon content and four types of soil with the low aggregation of "soft carbon" pre-treated by hydrogen peroxide or with all organic carbon removed by high temperature ignition from the original soil, were adopted as adsorbents. The effects of parameters (organic carbon content and composition, minerals, the initial TCE concentration, solution pH, moisture content and ionic strength) on TCE adsorption capacity were examined.
View Article and Find Full Text PDFThis study focused on acclimating a microbial enrichment to biodegrade benzene, toluene, ethylbenzene and xylenes (BTEX) in a wide range of salinity. The enrichment degraded 120 mg/L toluene within 5d in the presence of 2M NaCl or 150 mg/L toluene within 7d in the presence of 1-1.5M NaCl.
View Article and Find Full Text PDF1,1,1-Trichloroethane (TCA), a major organic and groundwater contaminant, has very strong toxic effects on humans, plants and microorganisms. Effects of TCA on enzymatic activity and microbial diversity were investigated in the anaerobic sequencing batch reactor (ASBR) under methanogenic, nitrate-reducing, sulfate-reducing and benzene/toluene degrading conditions. The activities of three enzymes (lactate dehydrogenase, phosphatase and protease) were significantly decreased in the presence of 5 mg/L TCA.
View Article and Find Full Text PDFA modified model based on the activated sludge model no. 3 was established to simulate a full-scale municipal wastewater treatment plant in Shanghai, China. The activated sludge model no.
View Article and Find Full Text PDFTwo dry anaerobic digestions of organic solid wastes were conducted for 6 weeks in a lab-scale batch experiment for investigating the start-up performances under mesophilic and thermophilic conditions. The enzymatic activities, i.e.
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