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Salinity has a significant impact on the sewage treatment efficiency of constructed wetlands (CWs), as well as affecting the greenhouse gas emissions of CWs. A lab-scale CW simulation system was constructed to observe the treatment efficiency and greenhouse gas flux occurring in CWs at different influent salinities (0%, 0.5%, 1.0%, 1.5%, and 2.0%). The results show that (1) the removal rates of COD, TN, NH4+-N, NO3−-N, and TP reach the highest at salinity of 0 or 0.5%. And the lowest removal rates are all at a salinity of 2.0%. (2) The emission flux of CO2, CH4, and N2O in CWs varies with an increase in salinity. The trends of CO2 and CH4 emission flux were consistent with those of COD reduction rate. However, it was opposite for N2O flux to that of TN, NH4+-N, and NO3−-N removal rate. Affected by salinity, the greenhouse gas emission flux in this study is generally lower than what was reported in literature. (3) Correlation analysis showed that CO2 and CH4 emission fluxes were positively correlated with the COD reduction rate. N2O emission flux was negatively correlated with the removal rates of TN, NH4+-N, and NO3−-N. The results suggest that different pollutants are inhibited by salinity to different degrees. COD is more affected by salinity than nitrogen and phosphorus, while nitrogen is more easily inhibited by salinity than phosphorus. CWs can have a high removal rate of pollutants in treating low-salinity wastewater. Although increased salinity reduces treatment efficiency of wastewater to some extent, it also inhibits the emission of CO2 and CH4.

Choosing suitable substrate is key to improving the efficiency of wetland decontamination. However, little is known about the effect of particle size. In order to study the effect of substrate type and size on COD, TN, and TP removal from sewage, 1-2, 2-4, and 4-8 mm zeolite, 2-4, 4-8, and 8-16 mm gravel, and 2-4, 3-5, and 6-8 mm anthracite were selected for establishment of the constructed system of experimental media with three replications. Results showed that removal efficiency of COD, TN, and TP varied with different particle sizes of the same material. The greatest COD removal was achieved with 4-8 mm zeolite and gravel and 6-8 mm anthracite, with removal rates of 53.74%, 60.76%, and 62.93%, respectively. Denitrification is the main pattern of nitrogen removal in the artificial test column; results show that smaller particle size is more effective for removal of TN. The removal rate of TP is also higher with smaller sizes of gravel and anthracite, but the opposite pattern occurred with zeolite. The removal of COD, TP, and TN also varied by substrate type. Anthracite led to good removal of COD, TP, and TN. Zeolite was most effective for removal of TN but had lower removal of TP. Gravel has high removal rate for COD, and has a general removal effect on TP.

Bismuth + proton pump inhibitor (PPI) + amoxicillin + levofloxacin is one of the bismuth quadruple therapy regimens widely used for the eradication of H. pylori infection. The recommended dosage of levofloxacin is 500 mg once daily or 200 mg twice daily to eradicate H. pylori infection. The aim of the present open-label, randomized control trial was to compare the effectiveness, safety, and compliance of different dosages of levofloxacin used to cure Helicobacter pylori infection. Eligible patients were randomly assigned to receive esomeprazole, amoxicillin, colloidal bismuth pectin and levofloxacin 500 mg once/day (group A) or levofloxacin 200 mg twice/day (group B) for 14 days. The primary outcome was the eradication rates in the intention-to-treat (ITT) and per protocol (PP) analyses. Overall, 400 patients were enrolled. The eradication rates in group A and group B were 77.5% and 79.5% respectively, in the ITT analysis, and 82.9% and 86.4%, respectively, in the PP analysis. No significant differences were found between two groups in terms of eradication rate, adverse effects or compliance. Oral levofloxacin 200 mg twice daily was similar in efficacy for eradicating H. pylori infection to oral levofloxacin 500 mg once daily but with lower mean total costs.

In this article, a novel transmit-reference (TR) signaling scheme is proposed for ultra-wideband (UWB) system, where by invoking m -sequence codes the reference and data pulses can be transmitted side by side to increase the data rate. This structure enables demodulation with a simple and practical autocorrelation receiver despite existence of severe inter-pulse interference (IPI). To evaluate detection performance of the new designs, closed-form expression for bit error probability (BRP) is theoretically derived and simulation results confirm the analytical results. In addition, the proposed scheme can be extended to M -ary systems to further improve the data rate and power efficiency.