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The aim of this study was to develop microbial electrolysis cell (MEC) with a novel acidophilic and autotrophic biocathode for treatment of acid wastewater. A biocathode was developed using acidophilic sulfate-reducing bacteria as the catalyst. Artificial wastewater with 200 mg L −1 sulfate and different Zn concentrations (0, 15, 25, and 40 mg L −1 ) was used as the MEC catholyte. The acidophilic biocathode dominated by Desulfovibrio sp. with an abundance of 66% (with 82% of Desulfovibrio sequences similar to Desulfovibrio simplex ) and achieved a considerable sulfate reductive rate of 32 g m −3 d −1 . With 15 mg L −1 Zn added, the sulfate reductive rate of MEC improved by 16%. The formation of ZnS alleviated the inhibition from sulfide and sped the sulfate reduction. With 15 and 25 mg L −1 Zn added, more than 99% of Zn was removed from the wastewater. Dissolved Zn ions in the catholyte were converted into insoluble Zn compounds, such as zinc sulfide and zinc hydroxide, due to the sulfide and elevated pH produced by sulfate reduction. The MEC with acidophilic and autotrophic biocathode can be used as an alternative to simultaneously remove sulfate and metals from acid wastewaters, such as acid mine drainage. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate different microbial electrolysis desalination cells for malic acid production. The systems included microbial electrolysis desalination and chemical-production cell (MEDCC), microbial electrolysis desalination cell (MEDC) with bipolar membrane and anion exchange membrane (BP-A MEDC), MEDC with bipolar membrane and cation exchange membrane (BP-C MEDC), and modified microbial desalination cell (M-MDC). The microbial electrolysis desalination cells performed differently in terms of malic acid production and energy consumption. The MEDCC performed best with the highest malic acid production rate (18.4 ± 0.6 mmol/L h) and the lowest energy consumption (0.35 ± 0.14 kW h/kg). The best performance of MEDCC was attributable to the neutral pH condition in the anode chamber, the lowest internal resistance, and the highest Geobacter percentage of the anode biofilm population among all the reactors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient H 2 production was realized in the single-chamber MEC at pH of 11.2. • H 2 yield was 7.72 mol H 2 / mol glucose with purity of 93.3 % under 1.6 V. • Acetate production from glucose fermentation was enhanced at pH of 11.2. • SAO-HM and HM were inhibited in the anodic and cathodic biofilms, respectively. Hydrogen production from food waste is of great significance for energy conversion and pollution control. The aim of this study was to investigate the glucose fermentation from food waste and hydrogen (H 2) production in the single-chamber microbial electrolysis cell (MEC) under hyperalkaline conditions. Single-chamber MECs were tested with 1 g/L glucose as substrate under different pH values (i.e., 7.0, 9.5, and 11.2) and applied voltages (i.e., 0.8, 1.2, and 1.6 V). With pH increase from 7.0 to 11.2, H 2 production with methanogenesis inhibition was significantly improved in the MEC. At pH of 11.2, the maximum current density reached 180 ± 9 A/m3 with the H 2 purity of 93.3 ± 1.2% and average H 2 yield of 7.72 ± 0.23 mol H 2 / mol glucose under 1.6 V. Acetate from glucose fermentation was the largest electron sink within 12 h. Methanobacterium alcaliphilum dominated the archaeal communities with the relative abundance of > 99.0% in the cathodic biofilms. The microbial communities and mcr A gene copy numbers analyses showed that high pH enhanced the acetate production from glucose fermentation, inhibited syntrophic acetate-oxidizing with hydrogenotrophic methanogenesis in the anodic biofilms, and inhibited hydrogenotrophic methanogenesis in the cathodic biofilms. Our results of hyperalkaline conditions provide a feasible way to harvest H 2 efficiently from fermentable substrates in the single-chamber MEC. [ABSTRACT FROM AUTHOR]

As the bioelectrochemical system, the microbial fuel cell (MFC) and the microbial electrolysis cell (MEC) were developed to selectively recover Cu and Ni ions from wastewater. The wastewater was treated in the cathode chambers of the system, in which Cu and Ni ions were removed by using the MFC and the MEC, respectively. At an initial Cu concentration of 500 mg ·L, removal efficiencies of Cu increased from 97.0%± 1.8% to 99.0%±0.3% with the initial Ni concentrations from 250 to 1000 mg·L, and maximum power densities increased from 3.1±0.5 to 5.4±0.6W·m. The Ni removal mass in the MEC increased from 6.8±0.2 to 20.5±1.5 mg with the increase of Ni concentrations. At an initial Ni concentration of 500 mg·L, Cu removal efficiencies decreased from 99.1%±0.3% to 74.2%±3.8% with the initial Cu concentrations from 250 to 1000 mg ·L, and maximum power densities increased from 3.0±0.1 to 6.3±1.2W·m. Subsequently, the Ni removal efficiencies decreased from 96.9%±3.1% to 73.3%±5.4%. The results clearly demonstrated the feasibility of selective recovery of Cu and Ni from the wastewater using the bioelectrochemical system. [ABSTRACT FROM AUTHOR]

Microbial desalination cell (MDC) is a promising technology to desalinate water and generate electrical power simultaneously. The objectives of this study were to investigate the desalination performance of monovalent and divalent cations in the MDC, and discuss the effect of ion characteristics, ion concentrations, and electrical characteristics. Mixed salt solutions of NaCl, MgCl, KCl, and CaCl with the same concentration were used in the desalination chamber to study removal of cations. Results showed that in the mixed salt solutions, the electrodialysis desalination rates of cations were: Ca >Mg>Na>K. Higher ionic charges and smaller hydrated ionic radii resulted in higher desalination rates of the cations, in which the ionic charge was more important than the hydrated ionic radius. Mixed solutions of NaCl and MgCl with different concentrations were used in the desalination chamber to study the effect of ion concentrations. Results showed that when ion concentrations of Na were one-fifth to five times of Mg, ion concentration influenced the dialysis more profoundly than electrodialysis. With the current densities below a certain value, charge transfer efficiencies became very low and the dialysis was the main process responsible for the desalination. And the phosphate transfer from the anode chamber and potassium transfer from the cathode chamber could balance 1%-3% of the charge transfer in the MDC. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the feasibility of tetramethylammonium hydroxide (TMAH) production using the microbial electrolysis desalination and chemical-production cell (MEDCC). With 1.0 g/L acetate in the anode chamber and tetramethylammonium chloride solutions with different concentrations in the desalination chamber, TMAH could be efficiently produced in the cathode chamber of MEDCC. With an applied voltage of 1.0 V, the concentration of TMAH reached 0.087 M within 17.5 h, with current efficiency of 52–58%. The electrical energy consumed for the TMAH production using the MEDCC was 0.76 kWh/kg, which was only 5–12% of that for the electrolysis and electrodialysis process. With the high value of TMAH produced in a friendly environment with low energy consumption, the MEDCC should be a potentially valuable method for the chemical production in practice. [ABSTRACT FROM AUTHOR]

Port State Control (PSC) can effectively improve crew and ship safety, reduce the probability of maritime accidents, and prevent marine environment from being polluted, playing a key role in the international shipping market. In order to effectively identify the degree of influence of various defects on the main types of ships in PSC inspection, a risk assessment matrix is constructed in this paper to determine the risk level of each detention defect. In addition, considering the association between various detention defects, this paper uses the CARMA algorithm to mine the association rules between various detention defects, so as to identify the defects that cause a higher risk of ship detention. The results show that for the existing six main ship types, Fire safety, Safety of Navigation, Life saving appliances and ISM have higher risks of ship detention and the risk of a ship being detained by a defect varies for different types of ships. In addition, corresponding recommendations are provided for port state control officer (PSCO) and ship managers to ensure ship safety based on the risk of deficiencies. This paper has reference value for shipping companies to effectively manage ships and improve the efficiency of port state inspection. • Evaluate the retention risk of defects in terms of both likelihood and severity. • Research on the detention risk of different ship type defects. • Provides targeted advice to all parties involved in the maritime industry • Combining extensive PSC retention data for research. [ABSTRACT FROM AUTHOR]

This study aims to investigate the expression levels of fibrinogen α chain (FGA) in human gastric cancer (GC) tissues and cell lines, clarify its role in gastric cancer progression, and explore its underlying mechanism. Bioinformatics analysis, Immunoblot, Immunohistochemical (IHC), and quantitative PCR assays were performed to assess the expression of FGA in human gastric cancer tissues and cell lines. CCK-8 and colony formation assays were performed to detect its role in the proliferation of gastric cancer cells. Wound healing, transwell, and Immunofluorescence were performed to detect its effects on gastric cancer cell motility and epithelial-mesenchymal transition (EMT) processes. Luciferase and CHIP assays were performed to confirm the transcriptional regulation of FGA on ITGA5. Immunoblot assays and double-label RFP-GFP-LC3 immunofluorescence analysis were conducted to detect its effects on gastric cancer cell autophagy and FAK/ERK pathway, and in vivo tumor growth assays were further performed. We found the low expression of FGA in human gastric cancer tissues and cell lines. FGA suppressed gastric cancer cell proliferation, motility, and EMT process, and stimulated cell autophagy. We further found that FGA suppressed the expression of Integrin-α5 (ITGA5) and inhibited the FAK/ERK pathway, therefore suppressing the progression of gastric cancer. The in vivo assays further confirmed that FGA suppressed tumor growth of gastric cancer cells in the BALB/c nude mice (18–22 g, female, 8-week-old) through suppressing ITGA5-mediated FAK/ERK pathway in mice. We demonstrated the mechanism underlying FGA suppressing gastric cancer progression, and therefore we thought FGA could serve as a tumor suppressor protein in gastric cancer. • FGA was low expressed in human gastric cancer tissues and cell lines. • FGA regulates the proliferation, motility, EMT, and autophagy of gastric cancer cells. • FGA promotes gastric cancer progression via ITGA5-mediated FAK/ERK pathway [ABSTRACT FROM AUTHOR]