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As a dewatering method of high moisture solid waste sludge, biodrying still faces environmental problems such as material loss and greenhouse gas emission in the process of treatment. In this study, biochar and magnesium chloride were used to explore the synergistic effect of enhancing sludge biodrying and reducing greenhouse gas emissions. The highest temperature of biodrying was raised to 68.2 °C within 3 days, extending the longest high-temperature period to 5 days, which reduced the water content to 28.8 % in the single addition of biochar treatment. The complex addition increased the NH4+-N content of materials by 57.49 % and decreased the NO3--N content of materials by 40.62 %. The use of additives significantly reduced the emissions of CO2, CH4, and N2O compared to the no-addition treatment. The increase in dominant Actinomycetes and Chloroflexibacter was the main reason for the reduction in gas emissions.

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The Slack channel (KCNT1, Slo2.2) is a sodium-activated and chloride-activated potassium channel that regulates heart rate and maintains the normal excitability of the nervous system. Despite intense interest in the sodium gating mechanism, a comprehensive investigation to identify the sodium-sensitive and chloride-sensitive sites has been missing. In the present study, we identified two potential sodium-binding sites in the C-terminal domain of the rat Slack channel by conducting electrophysical recordings and systematic mutagenesis of cytosolic acidic residues in the rat Slack channel C terminus. In particular, by taking advantage of the M335A mutant, which results in the opening of the Slack channel in the absence of cytosolic sodium, we found that among the 92 screened negatively charged amino acids, E373 mutants could completely remove sodium sensitivity of the Slack channel. In contrast, several other mutants showed dramatic decreases in sodium sensitivity but did not abolish it altogether. Furthermore, molecular dynamics (MD) simulations performed at the hundreds of nanoseconds timescale revealed one or two sodium ions at the E373 position or an acidic pocket composed of several negatively charged residues. Moreover, the MD simulations predicted possible chloride interaction sites. By screening predicted positively charged residues, we identified R379 as a chloride interaction site. Thus, we conclude that the E373 site and the D863/E865 pocket are two potential sodium-sensitive sites, while R379 is a chloride interaction site in the Slack channel.SIGNIFICANCE STATEMENT The research presented here identified two distinct sodium and one chloride interaction sites located in the intracellular C-terminal domain of the Slack (Slo2.2, KCNT1) channel. Identification of the sites responsible for the sodium and chloride activation of the Slack channel sets its gating property apart from other potassium channels in the BK channel family. This finding sets the stage for future functional and pharmacological studies of this channel.

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The 34-day anoxic storage of Pinus massoniana sawdust (PS) in a sealed constant temperature and humidity chambers was carried out to simulate the limited-oxygen storage process inside piles at industrial scale. The effects of anoxic storage on feedstock's properties and pelletization process were investigated with respect to elemental composition, dry matter loss, thermogravimetric characteristics, energy consumption, pellets' density, and microbial communities, etc. After anoxic storage, the microbial community of PS samples was altered, such as the fungi content (Clonostachys, Strelitziana, and Orbilia, etc.), resulting the elemental composition of PS was altered. Thus, the cellulose and ash content of the stored PS were increased, while the hemicellulose, volatile, and fixed carbon were decreased. The energy consumption was increased 7.85-21.98% with the increase in anoxic storage temperature and with the additive of fresh soil collected from PS field in storage process. The single pellet density was altered slightly. Meanwhile, the moisture uptake of PS pellets was decreased. After anoxic storage, the combustion behavior of the stored PS became more stable. The results can be applied directly to guide the development of commercial PS storage and pelletization process currently under development in Asia, Europe and North America.

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BACKGROUND: Recently, denervation therapy has been applied clinically for the treatment of intractable osteoarthritis (OA). This therapy provides an alternative for patients who are insensitive to conservative therapies or unwilling to receive surgery and general anesthesia. However, therapeutic effect of this method, especially the long-term efficacy, is still controversial. OBJECTIVES: The aim of this systematic review was to examine the efficacy of denervation therapy for the treatment of OA, especially on pain alleviation and functional recovery in the short and long term. STUDY DESIGN: This systematic review and meta-analysis was designed to investigate whether denervation therapy is more useful than conservative methods for achieving clinical outcomes in patients with refractory OA. METHODS: A literature search was performed in MEDLINE, EMBASE, and the Cochrane library for studies published from inception to August 2018. From those found meeting the search criteria, manuscripts comparing the clinical efficacy of denervation therapy and control agents, such as conservative therapies or sham operation, were included in this study. After reviewing the titles, abstracts, and the full text, 6 studies were included in the quantitative synthesis. Data, including postoperative pain scores, rate of 50% pain relief, and joint functional scores were extracted and combined to obtain effect size and statistical significance. RESULTS: In terms of postoperative pain intensity, denervation therapy showed significantly better short-term (4, 12, and 24 weeks) pain relief. The rates of 50% pain relief at 12 and 24 weeks after operation were also higher compared with the control group. In terms of joint functional improvement, denervation therapy showed favorable outcomes at 4 and 12 weeks after treatment, but no significant difference was found at 24 weeks after procedure between the groups. Overall, better results were reported in denervation therapy with a relative high-grade of evidence. LIMITATION: Analyses of long-term (one year and longer) effects could not be conducted owing to a lack of existing studies. CONCLUSIONS: Denervation of the knee joint may become a promising therapy for patients with knee OA who are refractory to conservative treatment. This therapy can provide short-term therapeutic effect in pain alleviation for 6 months and joint function recovery for 3 months. The therapeutic effect in joint function may decrease 6 months after operation. The long-term efficacy in pain remission and function improvement is still elusive and controversial; therefore, further research with larger sample sizes are needed in the future. KEY WORDS: Osteoarthritis, denervation therapy, radiofrequency, chronic pain, function, systematic review, meta-analysis.

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Effect of hydrothermal carbonization (HTC) on the hydrochar pelletization and the aldehydes/ketones emission from pellets during storage was investigated. Pellets made from the hydrochar were stored in sealed apparatuses for sampling. The energy consumption during pelletization and the pellets' properties before/after storage, including dimension, density, moisture content, hardness, aldehyde/ketones emission amount/rate and unsaturated fatty acid amount, were analyzed. Compared with untreated-sawdust-pellets, the hydrochar-pellets required more energy consumption for pelletization, and achieved the improved qualities, resulting in the higher stability degree during storage. The species and amount of unsaturated fatty acids in the hydrochar-pellets were higher than those in the untreated-sawdust-pellets. The unsaturated fatty acids content in the hydrochar-pellets was decreased with increasing HTC temperature. Higher aldehydes/ketones emission amount and rates with a longer emission period were found for the hydrochar-pellets, associated with variations of structure and unsaturated fatty acid composition in pellets.

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The high concentrations of CO (toxic) and CO2 (greenhouse gases) in blast furnace gas (a by-product of steelworks) reflect its low calorific value. In this study, anaerobic granular sludge was used to convert carbon from blast furnace gas to methane via exogenous hydrogen addition. The inhibition of methane production by CO partial pressure (P CO) was found to start from 0.4 atm. The intermediate metabolites from CO to methane including acetate, propionate, and H2 accumulated at higher CO concentrations in the presence of 2-bromoethanesulfonic acid. After the introduction of H2 and blast furnace gas, although the hydrogen partial pressure (P H2 ) up to 1.54 atm resulted in the maximum CH4 yield, the whole system was not stable due to the accumulation of a large amount of volatile fatty acids. The optimum P H2 on CH4 production from the simulated blast furnace gas, 5.32 mmol g-1 VSS, was determined at 0.88 atm in this study.

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In order to investigate the influence of hydrothermal carbonization (HTC) on the properties of the hydrochars, sawdust with a particle size below 0.45mm was treated in an autoclave at 200-260°C. The physical and chemical characteristics of products were studied, including proximate analysis, elemental composition, fiber content, surface area, bulk density, energy yield, color value, combustion activities and pyrolysis kinetics, etc. It showed that the color of hydrochars turned blacker, greener, and bluer after HTC. The ash, carbon, hydrogen and lignin contents showed a good correlation (R2>0.96) with color coordinates. The decrement in stage 1 and increment in stage 2 of temperature intervals were attributed to the volatile matters removal and fixed carbon accumulation, improving the stability and safety of hydrochars combustion. As shown by the Kissenger-Akahira-Sunose (KAS) and Coats-Redfern calculations, the HTC process can also make the pyrolysis more stable.

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The degradation of antibiotic levofloxacin was investigated by dimensionally stable anode as well as modified cathode using low-cost chemical reagents of hydrazine hydrate and ethanol for electro-Fenton in an undivided cell at pH 3.0 under room temperature. Comparison of unmodified and modified cathode was performed. The apparent rate constant of levofloxacin decay was found to be 0.2883 min-1 for graphite felt-10 with the best performance at 200 mA, which is lower than graphite felt at 400 mA. The optimum modified cathode showed a significant improvement of complete mineralization of levofloxacin, reaching a 92% TOC removal at 200 mA for 480 min higher than unmodified one at twice the current. Surface physicochemical properties and morphology were investigated by scanning electron microscope, contact angle and X-ray photoelectron spectroscopy. The electrochemical characterization of hydrogen evolution reaction was adopted to clarify a possible pathway for the higher mineralization of levofloxacin, indicating a potential pilot-scale study to the pollution with the similar structure.

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