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Objectives:: The nuclear factor-κB (NF-κB) signaling pathway plays an important role in regulating tubular epithelial-mesenchymal transition (EMT), an indispensable cellular programme for driving organ fibrosis and tumor progression. Liuwei Dihuang Decoction (LWD) is an effective Chinese formula for treating chronic renal failure. Methods:: First, by using morphological examination, immunofluorescence staining assay, RTqPCR, and Western blot analysis, in vitro experiments were designed to analyze NF-κB and EMT markers (including Snail, α-SMA, and E-cadherin) in transforming growth factor-β1 (TGF-β1) induced renal tubular epithelial cells (HK-2) and to detect the expression levels of LWD-CS cotreatment. Then, the recombinant lentiviral vector was overexpressed and knocked down by NF- κB and transfected into HK-2 cells. Cells were treated with TGF-β1 (10 ng/ml) with blank serum or LWD-containing serum, respectively, and the expression of these molecules in the NF-κB/Snail signaling pathway was further evaluated. Results:: Our results confirmed that TGF-β1 could induce EMT, nuclear translocation of NF-κB p65, and activate the NF-κB/Snail signaling pathway in HK-2 cells. Furthermore, NF-κB knocked-down dramatically increases the TGF-β1-induced mRNA and protein expression level of E-cadherin and reduces the level of Snail and α-SMA; this is reversed by NF-κB overexpression. LWD can decrease the EMT levels through the NF-κB/Snail signaling activation in TGF-β1-induced EMT of HK-2 cells. Conclusion:: The present study provides evidence suggesting a novel mechanism that LWD exerts anti-fibrosis effects through inhibiting activation of the NF-κB/Snail signaling pathway and consequently downregulating the TGF-β1-induced EMT in renal tubular epithelial cells.

Objective: To reduce the experimental error, three commonly used reference electrodes (Hg/HgO, Hg/Hg2Cl2 (SCE), and Ag/AgCl) are investigated to select the appropriate electrode in different aqueous electrolytes. Methods: Besides, the correct electrochemical test method is proposed according to the stability of the reference electrode. After measuring the potential difference of reference electrode in various aqueous electrolytes, it is found that Hg/HgO electrode is suitable for alkaline electrolytes, with minimum deviation in 6 M KOH solution, SCE should be used in acidic electrolytes, with minimum deviation in H2SO4 solution less than 1 M, and both SCE and Ag/AgCl electrode can be used in neutral electrolytes. Results: Due to the liquid junction potential, the result of using the double salt bridge is more accurate than that of using the single salt bridge. Conclusion: The stability of various reference electrodes in electrolytes is discrepant. Therefore, calibration is emphasized since the potential of the reference electrode drifts and even becomes invalid after prolonged use.

In the fusion reactor, the conducting liquid metals usually work in an environment of large temperature differences and strong magnetic field. The flow driven by the interaction of the Seebeck effect and magnetic field enlightens a promising approach to enhance heat transfer under strong magnetic field. Liquid metal thermal convection affected by the Seebeck effect and magnetic field is simulated using the partitioned iteration algorithm with liquid lithium as working fluid. It is found that the Seebeck effect can change energy transport pattern and greatly improve the heat transfer efficiency under strong magnetic field. With the increase of magnetic field intensity, the flow changes from steady vertical circulation to unsteady horizontal circulation and finally to steady horizontal circulation. The flow regime diagram based on the two dimensionless parameters, Gr / Te and Ha 2 / Te , can reflect the characteristics of different energy transport patterns. The flow generated by the Seebeck effect is most remarkable when O Ha 2 / Te ≈ 1 . The Nusselt numbers at different flow regimes show that the Seebeck effect can enhance the heat transfer efficiency of liquid metal under strong magnetic field about 50% and 90%, respectively, under different Glashof numbers.

Risk preference has constantly been one of the vital issues in economics and finance. In this study, the time series and term structure of Chinese investors’ implicit risk aversion are investigated using the implicit risk aversion extraction method, and the dynamic term structure of Chinese investors’ implicit risk aversion is modeled using the Vasicek model. In the empirical process, the SSE 50 ETF option data from March 2015 to July 2018 are adopted to extract model-free risk-neutral skewness. The standard deviation, skewness, and kurtosis of reality measure are extracted using the Shanghai 50 ETF data, and then the monthly implied risk aversion time series and term structure of Chinese investors are obtained. As indicated by the results of this study, the risk preference of Chinese investors exhibits significant time series characteristics, and it will show risk-loving and risk-averse phenomena at certain times. Moreover, for different periods in the future, differences are generated in investors’ risk preferences, suggesting an aversion to short-term risk and a certain tolerance for long-term risk, i.e., there are significant characteristics of the term structure. Besides, the term structure of implied risk aversion of Chinese investors is dynamically modeled using the Vasicek model. To be specific, its first principal component can account for 90% of the change in the term structure. The “level factor” refers to the critical factor load, and the level of long-term implied risk aversion reaches 0.658. Furthermore, the term structure of implied risk aversion exhibits the characteristics of mean regression. Next, more effective research results on investors’ risk preference are achieved, and the time-varying characteristics and term structure characteristics of investors’ risk preference are investigated. The result suggests that the long-term risk preference of Chinese investors approaches 1, and there is a significant feature of “mean regression,” i.e., a vital finding of this study.

Tunnel lining falling blocks can cause great threats to traffic safety, resulting in traffic interruptions or speed limits and endangering operational safety. Traditional lining disease remediation measures have low efficiency and high costs and are time consuming. Combining the research methods used in the literature, indoor testing, and model experiments, a very normal material, namely, polyurea spray film material, is proposed as a means by which to remediate the lining falling block disease in tunnels. A 1 : 1 tunnel lining structure model was established at the site, and four experimental conditions were tested. The experiments revealed that the tensile stress was less than the tensile strength and that no tensile fracture occurred in the polyurea spray film material under the joint action of the block’s self-weight and aerodynamic loads. Factors such as side seam treatment, surface sanding, and spray temperature may influence the bond strength of the polyurea spray film material. In order to remediate the issue of lining blocks falling, we recommended increasing the bond strength between the spray film material and the concrete or increasing the thickness of the polyurea spray film material.

Over the past few years, population growth, industrial progress and climate change have led to water scarcity. Thus, water pollution caused by hazardous soluble and insoluble pollutants, such as toxic metals and phenolic compounds, has become an important problem that should be dealt with urgently. For instance, new methods have been introduced to convert low-cost raw materials (i.e. coal fly ash and coal bottom ash “wastes-to-resource”) into suitable materials for new cleaner production to achieve sustainability goals in wastewater-containing toxic metals and phenolic compounds purification. Obviously, the functionalization of coal fly ash and bottom ash enhances the ability of coal ash-based entities as potential materials in wastewater remediation technologies. Here, we review the application of coal ashes, including coal bottom ash and fly ash-based materials for toxic metals and phenolic compounds removal. We also examine their structural properties and functionalization to enhance their affinities toward these pollutants in aqueous environment. Even though each process has its own benefits and limitations, coal ash-based materials appear promising for the removal of toxic metals and phenolic compounds using adsorption, membrane filtration, and photocatalysis. Overall, the study on the availability of coal fly ash and bottom ash for wastewater treatment have resulted in high removal efficiencies for toxic metals and phenolic compounds. In the future, new recycling methods for coal ashes as new water purification agents should be further studied and advanced processes should be investigated in order to achieve wastewater remediation purposes.