Hydraulic retention time optimization achieved unexpectedly high nitrogen removal rate in pilot-scale anaerobic/aerobic/anoxic system for low-strength municipal wastewater treatment.

Applications of post-denitrification processes are subjected to low reaction rates caused by a lack of carbon resources. To offer a solution for reaction rate promotion, this research found a pilot-scale anaerobic/aerobic/anoxic bioreactor treating 55-120 m3/d low-strength municipal wastewater for 273 days. A short hydraulic retention time (HRT, 5-6 h) and a high nitrogen removal rate (63.2 ± 9.3 g-N/m3·d) were achieved using HRT optimization. The effluent total nitrogen concentration was maintained at 5.8 ± 1.4 mg/L while operating at a high nitrogen loading rate of 86.2 ± 12.8 g-N/m3·d. The short aeration (1.25-1.5 h) minimized the Glycogen loss. The endogenous denitrification rate increased to above 1.0 mg/(g-VSS·h). The functional genus Ca. Competibacter enriched to 2.3 %, guaranteeing the efficient post-denitrification process. Dechloromonas rose to 1.1 %, aiding in the synchronous phosphorus removal. These findings offered fresh insights into AOA processes to achieve energy/cost-saving wastewater treatment.

[Effect and mechanism of Aconitum vaginatum on the proliferation, invasion and metastasis in human A549 lung carcinoma cells].

OBJECTIVE: To study the effects and mechanism of Aconitum vaginatum on proliferation, invasion and metastasis of human lung adenocarcinoma A549 cell lines. METHODS: A549 cells were treated with Aconitum vaginatum at different concentrations, and divided into 4 groups: Aconitum vaginatum 0.01, 0.1, 1 mg/mL groups and control group, respectively. MTT assay was used to evaluate cell proliferation; migration and invasion (with matrigel) assay was conducted in the transwell chamber; gelatin zymography was performed to evaluated the impacts of Aconitum vaginatum on matrix metalloproteinase (MMP)-2, MMP-9. RESULTS: Aconitum vaginatum exhibited a concentration-dependent inhibitory on proliferation and invasion of A549 cells. Aconitum vaginatum was also found to decrease the activity of MMP-2, MMP-9 in a concentration-dependent manner (P < 0.05). CONCLUSION: Aconitum vaginatum can inhibit the proliferation, invasion and metastasis of human adenocarcinoma A549 cell lines, the mechanism maybe deceasing MMP-2, MMP-9 activity.