2,860 research outputs found
Numerical solutions on fracture of piezoelectric materials by hybrid element
The cracked piezoelectric problem is observed numerically. To simulate the characteristic singularity at the crack tip, a plane piezoelectric hybrid element is derived. The new model involves displacement u, stress σo, electric displacement D and electric potential p as independent variables. The electromechanical coupling behavior of the cracked piezoelectric ceramics PZT-4 and PZT-5 is investigated. Under impermeable crack condition, the 1/√r-singularity at the crack-tip zone is exactly represented for σ and D. The efficiency of implementing the permeable crack condition is also inspected. To examine current energy release rate formulas, the path-independent integral is computed, and then a fitting formula for the energy release rate is obtained. In this paper, all the numerical results are compared with the previously reported theoretical solutions. © 2001 Elsevier Science Ltd. All rights reserved.postprin
Norcantharidin (NCTD) induces mitochondria mediated apoptosis in human HepG2 cells
Norcantharidin (NCTD), a demethylated form of cantharidin, is now in used as a routine anticancer drug. However, the detailed mechanisms underlying this process are generally unclear. The aims of this study were to evaluate the apoptotic effects and molecular mechanisms of NCTD. MTT assay was used to determine the cell growth inhibitory rate. Flow cytometry were used to detect the apoptosis and the loss of mitochondrial membrane potential (Δψm) induced by NCTD. Caspase detection kit were used to detect the activity of caspase-3 -9. Western-blot was used to detect the expression of Bcl-2, Bax and cytochrome C (cyt C). Our results indicated that, treatment of NCTD resulted in significant decrease in cell viability in a dose-and time-dependent manner. A dose-dependent apoptosis was also observed by flow cytometery analysis. Molecular mechanistic studies of apoptosis revealed that, NCTD treatment resulted in a significant loss of Δψm, release of cyt C, enhanced expression of pro-apoptotic protein Bax and suppression of anti-apoptotic protein Bcl-2. These were followed by activation of caspases-9 and -3, subsequently leading to cell apoptosis. These results indicate that, NCTD induced cytotoxicity in HepG2 cells by apoptosis, which is mediated through mitochondrial pathway.Key words: Norcantharidin, apoptosis, caspase, Bax/Bcl-2, cyto C, HepG2 cells
Miniaturized Multibeam Array Antenna Based on E-Plane Butler Matrix for 5G Application
© 2018 IEEE. A miniaturized multibeam array antenna fed by a compact beam-forming network (BFN) in multi-layer substrate integrated waveguide (SIW) technology is addressed. As the BFN, an E-plane 4 × 4 Butler matrix (BM) is designed. It is stacked with basic components in the vertical direction so that the dimension can be significantly reduced. Furthermore, some modifications of the BM have been made to obtain further miniaturization. The total occupied area of the designed antenna, including the BFN, is merely 3.8 1 × 0.5 1, which provides an attractive alternative for future 5G applications
High nuclear expression of STAT3 is associated with unfavorable prognosis in diffuse large B-cell lymphoma
<p>Abstract</p> <p>Background</p> <p>The purpose of the study was to investigate the expression and prognostic value of STAT3 in diffuse large B-cell lymphoma (DLBCL).</p> <p>Methods</p> <p>Seventy-four DLBCL patients from 2001 to 2007 were reviewed in the study. The STAT3 expression in their tumor tissues was examined using the immunohistochemistry (IHC) method, and evaluated for its association with clinicopathological parameters.</p> <p>Results</p> <p>Strong nuclear staining of STAT3 and phosphorylated-STAT3<sup>tyr705 </sup>(P-STAT3) were observed in 19 cases (25.7%) and 24 cases (32.4%), respectively, and the expression levels were highly consistent between them (<it>P </it>= 0.001). The high nuclear expression of STAT3 was more frequent in the non-germinal center B cell-like (non-GCB) DLBCL than that in the GCB subtype, but not reaching significance (<it>P </it>< 0.061). The high nuclear expression of STAT3 was found to be correlated with poor overall survival (OS) (<it>P </it>= 0.005). Multivariate Cox regression analysis showed that the STAT3 expression was an independent prognostic factor for DLBCL patients regardless of CHOP or R-CHOP regimen used as the first-line therapy.</p> <p>Conclusion</p> <p>STAT3 is more frequently expressed in non-GCB DLBCL than that in GCB subtype, and its strong nuclear expression is correlated with poor OS in DLBCL.</p
地心坐标系与站心坐标系中的速度转换及误差传播
Author name used in this publication: 伍吉仓Author name used in this publication: 邓康伟, Conrad TangAuthor name used in this publication: 陈永奇, Chen YongqiTitle in Traditional Chinese: 地心坐標系與站心坐標系中的速度轉換及誤差傳播Journal title in Traditional Chinese: 大地測量與地球動力學2005-2006 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
用边长变化结果计算地应变及块体划分
Author name used in this publication: 伍吉仓Author name used in this publication: 邓康伟, Conrad TangAuthor name used in this publication: 陈永奇, Chen YongqiTitle in Traditional Chinese: 用邊長變化結果計算地應變及塊體劃分Journal title in Traditional Chinese: 大地測量與地球動力學2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
三角形形状因子对地壳形变计算精度的影响
Author name used in this publication: 伍吉仓Author name used in this publication: 邓康伟, Conrad TangAuthor name used in this publication: 陈永奇, Chen YongqiTitle in Traditional Chinese: 三角形形狀因數對地殼形變計算精度的影響Journal title in Traditional Chinese: 大地測量與地球動力學2003-2004 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Inversion of GPS measurements for a layer of negative dislocation distribution in north China
Author name used in this publication: Wu, J. C.Author name used in this publication: Tang, H. W.Author name used in this publication: Chen, Y. Q.2003-2004 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
一种地应变显著性检验方法
Author name used in this publication: 陈光保Author name used in this publication: 陈永奇, Chen YongqiAuthor name used in this publication: 伍吉仓Author name used in this publication: 何秀凤Title in Traditional Chinese: 一種地應變顯著性檢驗方法Journal title in Traditional Chinese: 大地測量與地球動力學2009-2010 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
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