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The influence of erythromycin on ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) was investigated using batch and continuous experiments. During the batch experiments, the impact of erythromycin was strictly dose-dependent for AOB and NOB. The continuous addition of 1 mg/L of erythromycin in the long-term exposure experiment made NOB to be sensitive whereas AOB to be minimally sensitive. After a prolonged exposure to concentration, even up to 50 mg/L both NOB and AOB become insensitive to increases in erythromycin. From the seven dosage levels, between 54.3% and 69.1% of erythromycin was removed by adsorption and the percentage of nitrifiers in the microbial community increased from 39.8% to 55.6%.

Expression and function of Wnt signaling pathway in rats with atherosclerosis (AS) were investegated. The AS model of rats was established after 8-week continuous feeding of a high-fat diet, with normal rats as the control. Blood was taken from the carotid artery to detect the level of blood lipid. Aortic slices were made to observe the pathological changes of the aorta after the rats were sacrificed. Enzyme-linked immunosorbent assay kits were used to detect the contents of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Western blot analysis and semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) were performed to detect the expression levels of related proteins and mRNA in rat Wnt signaling pathway. Correlation analysis between the protein expression level of vascular endothelial growth factor (VEGF) and that of Wnt1 was conducted. Aortic slices showed that the ratio of intima thickness to media thickness of the rats in the model group was higher than that of in the control group (P

A self-agitation anaerobic baffled reactor (SA-ABR) was designed for treating waste substrate. The system uses the produced biogas to create a level difference in the chambers for agitation without any mechanical equipment. Computational fluid dynamics (CFD) models were used to investigate the influence of different configurations on the tracer diffusion. The results show that each self-agitation cycle includes an energy storage process, an exergonic process and a buffer stage. The compound transition phenomenon mainly occurs during the energy exergonic process and buffer stage. A higher U-tube would decrease the diffusion of the influent. The liquid level significantly affects the mixing in the reactor. The incomplete self-agitation could be improved by decreasing the U-tube height, increasing the difference of the liquid levels or decreasing the U-tube length. Furthermore, the two-stage agitation allows the reactor to behave as a two-phase system and the compounds in the two stages could partially be mixed.

The effect of the chemical oxygen demand/sulfate (COD/SO4(2-)) ratio on the anaerobic treatment of synthetic chemical wastewater containing acetate, ethanol, and sulfate, was investigated using a UASB reactor. The experimental results show that at a COD/SO4(2-) ratio of 20 and a COD loading rate of 25.2gCODL(-1)d(-1), a COD removal of as high as 87.8% was maintained. At a COD/SO4(2-) ratio of 0.5 (sulfate concentration 6000mgL(-1)), however, the COD removal was 79.2% and the methane yield was 0.20LCH4gCOD(-1). The conversion of influent COD to methane dropped from 80.5% to 54.4% as the COD/SO4(2-) ratio decreased from 20 to 0.5. At all the COD/SO4(2-) ratios applied, over 79.4% of the total electron flow was utilized by methane-producing archaea (MPA), indicating that methane fermentation was the predominant reaction. The majority of the methane was produced by acetoclastic MPA at high COD/SO4(2-) ratios and both acetoclastic and hydrogenthrophic MPA at low COD/SO4(2-) ratios. Only at low COD/SO4(2-) ratios were SRB species such as Desulfovibrio found to play a key role in ethanol degradation, whereas all the SRB species were found to be incomplete oxidizers at both high and low COD/SO4(2-) ratios.

The enrichment of nitrifying bacteria was realized and sludge yield was calculated for the batch experiment period. The influence of four kinds of antimicrobials on ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) was investigated using batch experiments. The specific ammonia-oxidizing activity (SAA) was 0.44 gN/gVSS/d and the specific nitrite-oxidizing activity (SNA) was 0.64 gN/gVSS/d. Below 400 mg/L antimicrobials, Cefalexin (CLX) almost has no adverse effect on nitrification and the highest inhibition caused by Sulfamethoxazole (SMX) was 15.4% and 23.9% to SAA and SNA respectively. Azithromycin (AZI) exhibited the most intense inhibitory effect. The relative activity of AOB and NOB were 39.0% and 29.8% respectively when AZI was 400 mg/L. Due to the complexation of Tetracycline (TC) with Ca and Mg, biomass showed obvious reduction with the foam on water surface. With the addition of 400 mg/L TC, only 76.9%, 13.7% and 8.1% of sludge remained when the substrate contained calcium or magnesium ions or both of them respectively.

Potential reuse of dewatered sludge (DS) and municipal solid waste incineration (MSWI) bottom ash as components to develop controlled low-strength material (CLSM) was explored. The effects of DS:MSWI bottom ash:calcium sulfoaluminate (C S ¯ A) cement ratio and thermal treatment of MSWI bottom ash at 900 °C on the mechanical and microstructural properties of CLSM were intensively studied to optimize the process. Results showed DS and MSWI bottom ash could be utilized for making CLSM. The CLSM prepared with milled MSWI bottom ash gave higher unconfined compressive strength (UCS) of 2.0–6.2 MPa following 1 year of curing at 1.0:0.1:0.9 ≤ DS:MSWI bottom ash:C S ¯ A ≤ 1.0:0.8:0.2. However, the corresponding strengths for CLSM containing thermally treated MSWI bottom ash ranged from 0.7 to 4.6 MPa, decreasing 26–65%. The microstructural analysis by X-ray powder diffraction (XRD), Fourier transforms infrared spectroscopy (FT-IR), as well as scanning electron microscopy (SEM) combined with an energy dispersive X-ray spectroscopy (EDS) revealed that ettringite (C 3 A·3C S ¯ ·H 32 , or AFt) crystals were the most important strength-producing constituents which grew into and filled the CLSM matrix pores. Milled MSWI bottom ash addition favored the formation of highly crystalline AFt phases and accordingly enhanced compressive strengths of CLSM specimens. In contrast, thermal treatment at 900 °C produced new phases such as gehlenite (Ca 2 Al 2 SiO 7 ) and hydroxylapatite (Ca 5 (PO 4 ) 3 (OH)), which deteriorated the pozzolanic activity of bottom ash and caused the strengths to decrease. Leaching tests evidenced that leachable substances from CLSM samples exhibited negligible health and environmental risks. The results of this study suggested that MSWI bottom ash can be effectively recycled together with DS in developing CLSM mixtures with restricted use of C S ¯ A cement.

The influence of Cephalexin (CLX), Tetracycline (TC), Erythromycin (ERY) and Sulfathiazole (ST) on methane-producing archaea (MPA) and sulfate-reducing bacteria (SRB) in anaerobic sludge was investigated using acetate or ethanol as substrate. With antimicrobial concentrations below 400 mg L −1 , the relative specific methanogenic activity (SMA) was above 50%, so that the antimicrobials exerted slight effects on archaea. However ERY and ST at 400 mg L −1 caused a 74.5% and 57.6% inhibition to specific sulfidogenic activity (SSA) when the sludge granules were disrupted and ethanol used as substrate. After disruption, microbial tolerance to antimicrobials decreased, but the rate at which MPA utilized acetate and ethanol increased from 0.95 gCOD·(gVSS⋅d) −1 to 1.45 gCOD·(gVSS⋅d) −1 and 0.90 gCOD·(gVSS⋅d) −1 to 1.15 gCOD·(gVSS⋅d) −1 respectively. The ethanol utilization rate for SRB also increased after disruption from 0.35 gCOD·(gVSS⋅d) −1 to 0.46 gCOD·(gVSS⋅d) −1 . Removal rates for CLX approaching 20.0% and 25.0% were obtained used acetate and ethanol respectively. The disintegration of granules improved the CLX removal rate to 65% and 78%, but ST was not removed during this process.