Comprehensive Analysis of the Dilatation During Bainitic Transformation Under Stress

Ming-xing Zhou,Guang Xu,Li Wang,Zheng-liang Xue,Hai-jiang Hu 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.6

The thermal simulation experiments on bainitic transformation were conducted on Gleeble 3800. The microstructures of specimens were examined by scanning electron microscopy. The main purpose is to investigate the relationship between the dilatation of specimens and bainitic transformation under stress. Results show that the radial strain cannot represent the real amount of bainitic transformation under stress because the radial strain contains both shear and dilatational components of invariant plane strain. In this case, the volume strain, which eliminates the influence of the shear components, should be used to analyze the amount of bainitic transformation under stress. In addition, the radial strain should not be used for the investigation of the kinetics of bainitic transformation under stress. For bainitic transformation without stress, the radial strain of the specimen can represent the amount of bainite, and can be used for the analysis of the kinetics of bainitic transformation; so it is not necessary to measure the volume strain. The present study clarifies the relationship between dilatation and the bainitic transformation under stress, and provides a useful reference to the analysis of bainitic transformation under stress.

Expression and Clinical Significance of Osteopontin in Calcified Breast Tissue

Huan, Jin-Liang,Xing, Li,Qin, Xian-Ju,Gao, Zhi-Guang,Pan, Xiao-Feng,Zhao, Zhi-Dong Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.10

Osteopontin (OPN) is an integrin-binding protein, believed to be involved in a variety of physiological cellular functions. The physiology of OPN is best documented in the bone where this secreted adhesive glycoprotein appears to be involved in osteoblast differentiation and bone formation. In our study, we used semi-quantitative RT-PCR of osteopontin in calcification tissue of breast to detect breast cancer metastasis. The obtained data indicate that the expression of osteopontin is related to calcification tissue of breast, and possibly with the incidence of breast cancer. The expression strength of OPN by RT-PCR detection was related to the degree of malignancy of breast lesions, suggesting a close relationship between OPN and breast calcification tissue. The results revealed that expression of OPN mRNA is related to calcification of breast cancer tissue and to the development of breast cancer. Determination of OPN mRNA expression can be expected to be a guide to clinical therapy and prediction of the prognosis of breast cancer patients.

β-elemene Induces Caspase-dependent Apoptosis in Human Glioma Cells in vitro through the Upregulation of Bax and Fas/FasL and Downregulation of Bcl-2

Li, Chen-Long,Chang, Liang,Guo, Lin,Zhao, Dan,Liu, Hui-Bin,Wang, Qiu-Shi,Zhang, Ping,Du, Wen-Zhong,Liu, Xing,Zhang, Hai-Tao,Liu, Yang,Zhang, Yao,Xie, Jing-Hong,Ming, Jian-Guang,Cui, Yu-Qiong,Sun, Ying Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Background: ${\beta}$-elemene, extracted from herb medicine Curcuma wenyujin has potent anti-tumor effects in various cancer cell lines. However, the activity of ${\beta}$-elemene against glioma cells remains unclear. In the present study, we assessed effects of ${\beta}$-elemene on human glioma cells and explored the underlying mechanism. Materials and Methods: Human glioma U87 cells were used. Cell proliferation was determined with MTT assay and colony formation assay to detect the effect of ${\beta}$-elemene at different doses and times. Fluorescence microscopy was used to observe cell apoptosis with Hoechst 33258 staining and change of glioma apoptosis and cell cycling were analyzed by flow cytometry. Real-time quantitative PCR and Western-blotting assay were performed to investigated the influence of ${\beta}$-elemene on expression levels of Fas/FasL, caspase-3, Bcl-2 and Bax. The experiment was divided into two groups: the blank control group and ${\beta}$-elemne treatment group. Results: With increase in the concentration of ${\beta}$-elemene, cytotoxic effects were enhanced in the glioma cell line and the concentration of inhibited cell viability ($IC_{50}$) was $48.5{\mu}g/mL$ for 24h. ${\beta}$-elemene could induce cell cycle arrest in the G0/G1 phase. With Hoechst 33258 staining, apoptotic nuclear morphological changes were observed. Activation of caspase-3,-8 and -9 was increased and the pro-apoptotic factors Fas/FasL and Bax were upregulated, while the anti-apoptotic Bcl-2 was downregulated after treatment with ${\beta}$-elemene at both mRNA and protein levels. Furthermore, proliferation and colony formation by U87 cells were inhibited by ${\beta}$-elemene in a time and does-dependent manner. Conclusions: Our results indicate that ${\beta}$-elemene inhibits growth and induces apoptosis of human glioma cells in vitro. The induction of apoptosis appears to be related with the upregulation of Fas/FasL and Bax, activation of caspase-3,-8 and -9 and downregulation of Bcl-2, which then trigger major apoptotic cascades.

Effect of Ausforming on the Stability of Retained Austenite in a C-Mn-Si Bainitic Steel

Hai-jiang Hu,Guang Xu,Li Wang,Ming-xing Zhou,Zheng-liang Xue 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.5

The effect of ausforming on the stability of retained austenite in a C-Mn-Si bainitic steel was investigated through metallography, X-ray diffraction and dilatometry. The geometrical relationships of the amount of bainite transformation and the volume fractions of retained austenite with deformation strains were studied. The results show that the degree of promotion of small strains on bainite transformation is nonlinear because of the dual effects of accelerated nucleation and retarded growth caused by ausforming. The transformed bainite fraction first increased and then decreased with increased small strains. It indicates that there is a maximum degree of the promotional function corresponding to a certain small strain at low temperature. Although small strains promote bainite transformation, a larger quantity of retained austenite exists at room temperature due to the suppressed martensite transformation during the cooling process after bainite transformation. The carbon content in retained austenite increases with the amount of baintie transformation, which contributes to the stability of austenite. Compared with the stabilizing effect due to carbon enrichment, mechanical stabilization caused by ausforming has a decisive effect on determining the volume fraction of retained austenite after isothermal bainite transformation.

Transient propagation of BmLV and dysregulation of gene expression in nontarget cells following BmLV infection

Feng Yongjie,Zhang Xing,Kumar Dhiraj,Kuang Sulan,Liu Bo,Hu Xiaolong,Zhu Min,Liang Zi,Cao Guangli,Xue Renyu,Gong Chengliang 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.3

Bombyx mori latent virus (BmLV), a novel positive-strand RNA virus was first identified in the B. mori cultured BmN cell line. Whether the infectivity of BmLV to silkworm larvae and non-silkworm cells is connected with dysregulation of gene expression are not well understood. A complete sequence of BmLV genomic RNA was identified and revealed that a fragment with 495 nt in length was deleted from the RNA-dependent RNA poly merase (RdRp) gene in some BmLV genomic RNAs. Studies on the infectivity of BmLV to nontarget cells showed that BmLV can infect silkworm larvae, Spodoptera frugiperda Sf-9 and H1299 lung cancer cells with transient propagation. The dysregulation of gene expression of Sf-9 cells followed by BmLV infection was analyzed. Out of 743 differentially expressed genes (DEGs), 300 were upregulated and 443 were downregulated. Gene Ontology (GO) analysis indicated the DEGs were enriched into oxidoreductase activity for CH-NH 2 group donors, gluta mate biosynthetic process, response to stress and proteasome core complex. KEGG enrichment analysis showed that DEGs were mainly enriched into sulfur metabolism, RNA degradation, proteasome, pentose and glucuronate interconversions. Undesirable nutrients and temperature factors contributed to the propagation of BmLV in Sf-9 cells. Additionally, the Imd and RNAi pathways were activated by BmLV infection without stimulating Toll and JAK-STAT pathways. Therefore, it is suggested that BmLV is originated from plants, which can enter nontarget cells with transient propagation. The transient infection of BmLV may not only be regulated by Imd and RNAi immune pathways but also mediated by dysregulation of gene expression.

Enhanced thermoelectric performance of P-type Sb2Te3 thin films through organic-inorganic hybridization on flexible substrate

Zhuang-hao Zheng,Jing-ting Luo,Feng Li,Guang-xing Liang,Ping Fan 한국물리학회 2019 Current Applied Physics Vol.19 No.4

In this work, a new idea of organic-inorganic hybridization was proposed to fabricate flexible p-type - Sb2Te3/ CH3NH3I thin films. The CH3NH3I has a strong adsorption which can promote the growth of organic molecules, improve the crystallization, and finally increase electrical conductivity. Post-annealing of the fabricated films increased the phonon scattering, thus resulting in a reduction of thermal conductivity and an increased ZT value. The annealed hybrid-composite film showed a significant enhancement in thermoelectric performance, with a maximum ZT value of 0.94 at a temperature of 413 K, which is twice as large as that of the as-deposited film.

Enhanced Room-Temperature Thermoelectric Performance of In-Doped ZnO:Al Thin Films through Prefabricated Layer Doping Method

Ping Fan,Zhuang-Hao Zheng,Jing-Ting Luo,Guang-Xing Liang,Dong-Ping Zhang 대한금속·재료학회 2015 ELECTRONIC MATERIALS LETTERS Vol.11 No.3

In this study, AZO thin films prepared by direct current reactive magnetron sputtering using a Zn-Al alloy target and In with varied content were doped through the prefabricated layer doping method in order to optimize their thermoelectric properties. The effects of In content on the room temperature microstructure and thermoelectric properties of the AZO thin films were investigated. It was found that the absolute value of the Seebeck coefficient of the thin films increases stably after In doping and reaches 153 μV·K−1 when the In content is 0.71%. Though the electrical conductivity of In-doped thin films is smaller than those of the un-doped films, the power factor of the thin films shows a significant increase after In doping with a maximum value of 2.22 × 10−4 W·m−1·K−2, which is several times that of the un-doped films.