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To meet the use needs of LNG fuel tanks and storage tanks， the key process control of steel-making and rolling of 9Ni steel were carried， and the influence of two-phase area heat-treatment processes and Nb microalloying on micro⁃ structure and properties of 9Ni steel was studied. The results show that with the increase of intercritical quenching （IQ） temperature， the Yield stress（YS）， tensile strength （TS） and the ratio between YS and TS （Y/T） decreases firstly， then increases. Subsequently as the tempering temperature increases， the YS and TS gradually decrease， while the elongation increases； When the tempering temperature is 600 ℃， the YS and TS reach their lowest values， and the elongation （EL） reaches its peak. The microstructure after intercritical quenching presents distribution of large and small grains， which contributes to the reduction of Y/T ratio of steel plate. The microstructure of Nb micro-alloyed 9Ni low-temperature steel plate is mainly composed of tempered sorbite structure and 3% -8% reverse austenite. The addition of 0. 015% Nb in⁃ creases the average YS and TS of 9Ni low-temperature steel by about 50 MPa and 40 MPa， respectively. The impact ab⁃ sorption energy increases by about 40 J tested at -196 ℃.

Purpose: To examine whether ionizing radiation enhances the migratory and invasive abilities of cancer cells through transforming growth factor (TGF-β)–mediated epithelial–mesenchymal transition (EMT). Methods and Materials: Six cancer cell lines originating from different human organs were irradiated by 60Co γ-ray at a total dose of 2 Gy, and the changes associated with EMT, including morphology, EMT markers, migration and invasion, were observed by microscope, Western blot, immunofluorescence, scratch assay, and transwell chamber assay, respectively. Then the protein levels of TGF-β in these cancer cells were detected by enzyme-linked immunosorbent assay, and the role of TGF-β signaling pathway in the effect of ionizing radiation on EMT was investigate by using the specific inhibitor SB431542. Results: After irradiation with γ-ray at a total dose of 2 Gy, cancer cells presented the mesenchymal phenotype, and compared with the sham-irradiation group the expression of epithelial markers was decreased and of mesenchymal markers was increased, the migratory and invasive capabilities were strengthened, and the protein levels of TGF-β were enhanced. Furthermore, events associated with EMT induced by IR in A549 could be reversed through inhibition of TGF-β signaling. Conclusions: These results suggest that EMT mediated by TGF-β plays a critical role in IR-induced enhancing of migratory and invasive capabilities in cancer cells. [Copyright &y& Elsevier]

Background: Chronic atrophic gastritis (AG) with intestinal metaplasia (IM) significantly increases the risk of gastric cancer. Some medicines have showed definite therapeutic effects in AG and IM regression., Aim: To validate the efficacy of Lamb's tripe extract and vitamin B 12 capsule (LTEVB 12 ) initial therapy and celecoxib rescue therapy for IM and AG., Methods: A total of 255 patients were included to receive LTEVB 12 initial therapy (2 capsules each time, three times daily for 6 mo) in hospital in this study. The patients with failure of IM regression continued to receive celecoxib rescue therapy (200 mg, once daily for 6 mo). After each therapy finished, the patients underwent endoscopy and biopsy examination. The regression efficiency was assessed by the operative link on gastritis assessment (OLGA) and the operative link on the gastric intestinal metaplasia assessment (OLGIM) staging system. Logistic regression analysis was applied to identify factors associated with the curative effect., Results: For LTEVB 12 initial therapy, the reversal rates of IM and AG were 52.95% and 48.24%, respectively. Analogously, for celecoxib rescue therapy, the effective rates for IM and AG were 56.25% and 51.56%, respectively. The IM regression rate of complete therapy was up to 85.03%. In different OLGA and OLGIM stages of IM patients, therapeutic efficiency showed a significant difference in each group ( P < 0.05). For both therapies, patients with high stages (III or IV) of both the OLGA and OLGIM evaluation systems showed a higher IM or AG regression rate than those with low stages (I or II). Among patients with high stages (OLGIM III and IV), the IM regression rate was above 70% for each therapy. Eating habits, fresh vegetable intake, and high-salt diet were identified as independent factors for the IM reversal effect of LTEVB 12 therapy, especially high-salt diet (odds ratio = 1.852, P < 0.05)., Conclusion: Monotherapy could reverse IM and AG. LTEVB 12 initial therapy and celecoxib rescue therapy significantly increase the regression effect. IM may not be the point of no return among gastric precancerous lesions., Competing Interests: Conflict-of-interest statement: The authors declare that they have no conflict of interest to disclose., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)

Objective: To study the effects of electromagnetic pulses (EMP) on pathological changes and apoptosis of spleen lymphocytes in mice., Methods: The male BALB/c mice (18 ∼ 22 g) were sham-exposed or exposed to EMP at 200 kV/m for 400 pulses a day for 7 days. On the 1st, 3rd, 7th, 14th 28th days after exposure the mice were killed. The weight of mice, the pathological change and the weight of mouse spleens were observed, the spleen indexes were calculated. The lymphocytes extracted from spleens were counted. The apoptosis and cell cycle of the lymphocyte were detected by flow cytometry, and the migration of the lymphocyte was measured by transwell assay., Results: No pathological changes were found on the first day after exposure. However, the expanded sinusoid and the changed structure of spleen corpuscle on the 3rd day after exposure were observed. There was no difference of spleen indexes between the sham group and the exposure group on the 1st and 14th day after exposure. On the 3rd and 7th days after exposure, the spleen indexes of exposure group were significantly higher than those of sham-exposure group (P < 0.05). On the 28th day after exposure, the spleen indexes of exposure group was significantly lower than those of sham-exposure group (P < 0.05). The number of spleen lymphocytes on the 3rd and 7th days after exposure in exposure group increased significantly, compared with sham-exposure group (P < 0.05). But there were no differences of apoptotic cells and cellular cycle between the exposure group and sham-exposure group (P > 0.05). The ability of migration of the exposure group was significantly higher than that of sham-exposure group (P < 0.05). than the sham group (P < 0.05)., Conclusion: The spleen of the male mouse is one of the target organs of EMP. After exposure to EMP, the number of spleen lymphocytes increased. But there were no differences of cell apoptotic cells and cell cycle between the sham group and the exposure group, due to the enhanced migration of lymphocytes induced by EMP.