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[Introduction] In order to improve heat exchange efficiency, the condensate pipelines, main water supply pipelines drain pipelines and partial extraction pipelines of nuclear power plants are all coated outside the pipelines. At present, the test methods of ferromagnetic pipelines are mainly conventional ultrasound and ultrasonic guided waves. These test methods are limited by the detection environment and preconditions, which increase the difficulty of test. In order to improve the test efficiency of pipelines with insulation layer, we shall enrich technical methods, shorten maintenance period and improve economic benefit of nuclear power plant. [Method] This paper mainly studied the feasibility and reliability of pulsed eddy current testing method under low frequency electromagnetic interference in nuclear power plant, and used the measured and calculated values of the induced voltage to establish the optimal parameter inversion problem. In combination with the coupling relationship between the parameters and based on the time-domain analytical solution of the pipeline pulsed eddy current field, the paper established the specific relationship between the measured value and the calculated value of the induced voltage, and established the optimization parameter inversion problem. In combination with the coupling relationship between the parameters, the paper proposed a pulsed eddy current detection method for in-service operation and maintenance of insulated pipes in nuclear power plants. [Result] Using the pulsed eddy current detection method for the relative wall thickness of ferromagnetic pipelines proposed in this paper, in-service sample pipelines of nuclear power plant are tested and the testing result is compared with conventional ultrasonic testing. The error of the two testing results is about 5%. [Conclusion] The testing results of impulse eddy current testing are reliable and it is suitable for non-destructive testing and evaluation of nuclear power plant ferromagnetic pipeline wall thickness corrosion thinning.

Fe-Mn-Al-C lightweight steels have been of significant interest due to their excellent mechanical properties and unique microstructures. However, there has been limited focus on the dynamic deformation. Here, we systematically investigate the mechanical responses over various strain rates and corresponding microstructure evolution in quasi-static and dynamic compression to reveal the transition of deformation mechanisms. The present lightweight steel exhibits a significant strain rate effect, with the yield strength increasing from 735.8 to 1149.5 MPa when the strain rate increases from 10−3 to 3144 s−1. The deformation in ferrite under high-strain-rate loading is dominated by wave slip, forming a cellular structure (cell block). Meanwhile, the deformation in austenite is dominated by planar slip, forming dislocation substructures such as high-density dislocation walls and microbands. In addition, the deformation twinning (including secondary twinning)- and microband-induced plasticity effects are responsible for the excellent dynamic compression properties. This alloy delays damage location while maintaining high strength, making it ideal for shock loading and high-strain-rate applications. The Johnson–Cook (J–C) constitutive model is used to predict the deformation behavior of lightweight steel under dynamic conditions, and the J–C model agrees well with the experimental results.

Objective To investigate the anti-metastatic effects of Babao Dan (BBD) on gastric cancer (GC) cells (AGS and MGC80-3) and explore the underlying molecular mechanisms by which it inhibits epithelial–mesenchymal transition (EMT). Methods AGS and MGC80-3 cells were treated with BBD. In addition, cells were treated with the EMT inducer transforming growth factor-β1 (TGF-β1). Cell viability was determined using the MTT assay, and the live cell ratio was calculated via cell counting. Cell invasion and migration were evaluated using the Transwell assay. Western blotting was performed to measure the protein expression of EMT biomarkers and related genes. Results BBD inhibited the viability, migration, and invasion of AGS and MGC80-3 cells, but it did not reduce the live cell ratio. Furthermore, BBD inhibited the expression of N-cadherin, vimentin, zinc finger E-box binding homeobox (ZEB)1, ZEB2, Twist1, matrix metalloproteinase (MMP)2, MMP9, TGF-β1, and p-Smad2/3, whereas E-cadherin expression was increased in AGS and MGC80-3 cells to different degrees. Using a GC cell model of EMT induced by TGF-β1, we proved that BBD inhibited p-Smad2/3 and N-cadherin expression, cell migration, and cell invasion. Conclusion BBD suppressed cell migration and invasion by inhibiting TGF-β–induced EMT and inactivating TGF-β/Smad signaling in GC cells.

The Toll-like receptor 3 (TLR3) agonists as polyriboinosinic–polyribocytidylic acid (poly (I:C)) have been implicated as potential immunotherapy adjuvant for cancer whereas the exact roles of TLR3 agonists in hepatocellular carcinoma (HCC) treatment have not been clearly evaluated. In consistent with previous reports, we found that poly (I:C) triggering of TLR3 inhibited cell proliferation and induced apoptosis in HCC cells. However, poly (I:C), when used at lower concentration that cannot remarkably inhibit proliferation and induce apoptosis in HCC cells, enhanced the migration and invasion in vitro and the metastasis in vivo. More importantly, we found that bufalin, a prominent component of toad venom, could suppress poly (I:C)-inspired migration, invasion and metastasis of HCC cells despite that bufalin could not potentiate poly (I:C)-induced inhibition of proliferation and induction of apoptosis. In MHCC97 H cells, bufalin impaired poly (I:C)-induced activation of Tank-binding kinase 1 (TBK1) and interferon regulatory factor 3 (IRF3) pathway and NF-κB pathway. Inhibitor for TBK1 but not NF-κB suppressed poly (I:C)-inspired migration and invasion, which was further supported by using TBK1 deficient (Tbk1–/–) cells. In another model using poly (I:C) transfection, bufalin could also suppress the migration and invasion of HCC cells, which was not observed in Tbk1–/– MHCC97 H cells. Our data suggest that bufalin can suppress the metastasis of HCC cells in poly (I:C) therapy by impairing TBK1 activation, indicating that bufalin may be used in combination with poly (I:C) therapy in HCC treatment for the sake of reversing poly (I:C)-triggered metastasis of HCC cells.

Emodin, an anthraquinone derivative from the root and rhizome of Rheum palmatum L., was found to have antitumor effects in different types of cancer by regulating multi-molecular targets. The aim of the present study was to explore the effect of emodin on the migration and invasion of MHCC-97H human hepatocellular carcinoma cells and the underlying molecular mechanisms. Firstly, it was demonstrated that emodin can inhibit cell proliferation and induce apoptosis of cells in a time- and dose-dependent manner, using a MTT assay and flow cytometry, respectively. However, when emodin concentration was <50 μmol/l, it had little effect on the inhibition of proliferation or the induction of apoptosis. Then, it was observed that emodin can significantly suppress cell migration and invasion with a treatment dose <50 μmol/l compared with the control (P<0.05), which was not attributed to a decrease in cell number. Further study demonstrated that emodin significantly suppressed the expression levels of matrix metalloproteinase (MMP)-2 and MMP-9 compared with the control, which may be mediated by the activation of the p38 mitogen-activated protein kinases (MAPK) signaling pathway and suppression of extracellular signal regulated kinase (ERK)/MAPK and phosphatidylinositol 3-kinase/Akt signaling pathways. Therefore, the present study, for the first time, used MHCC-97H cells, which have the high potential of malignant invasion, to demonstrate that emodin may inhibit cell migration and invasion. [ABSTRACT FROM AUTHOR]

A mesoporous boehmite (γ-AlOOH) synthesis and vanadate (V(V)) ion adsorption and desorption on the mesoporous γ-AlOOH were investigated. The synthesis and adsorption studies showed that the mesoporous γ-AlOOH with a BET surface of 442 m2 g-1 and a pore size of 2.75 nm possessed a maximum V(V) ion adsorption capacity of 3.28 mmol g-1. The adsorption mechanism results showed that the mesoporous γ-AlOOH liberated surface hydroxyls to form coordinatively unsaturated AlVI centres to adsorb V(V) ions which connected oxygen of the coordinatively unsaturated AlVI centres with mono-oxo, VvO terminal double bonds. The desorption studies showed that the V(V) ions could be desorbed by NH3·H2O easily. In the cleaner production application of chromate, the mesoporous γ-AlOOH was synthesized in the Na2CrO4-NaAlO2-NaVO3-H2O solutions of the chromate production and then in situ adsorbed the V(V) ions. The results showed that the V(V) ions were removed effectively, so that the highly carcinogenic CaCrO4 containing Ca(VO3)2 residue which was obtained by the typical process of chromate production was eliminated. Therefore, green separation of V(V) ions to reduce waste pollution ensuring economy and feasibility could be expected. [ABSTRACT FROM AUTHOR]