Intermediate-pressure phases of cerium studied by an LDA + Gutzwiller method

The thermodynamic stable phase of cerium metal in the intermediate pressure regime (5.0--13.0 GPa) is studied in detail by the newly developed local-density approximation (LDA)+ Gutzwiller method, which can include the strong correlation effect among the 4\textit{f} electrons in cerium metal properly. Our numerical results show that the $\alpha"$ phase, which has the distorted body-centered-tetragonal structure, is the thermodynamic stable phase in the intermediate pressure regime and all the other phases including the $\alpha'$ phase ($\alpha$-U structure), $\alpha$ phase (fcc structure), and bct phases are either metastable or unstable. Our results are quite consistent with the most recent experimental data.Comment: 17 pages, 7 figure

The Reduced Order Method for Solving the Linear Complementarity Problem with an M-Matrix

In this paper, by seeking the zero and the positive entry positions of the solution, we provide a direct method, called the reduced order method, for solving the linear complementarity problem with an M-matrix. By this method, the linear complementarity problem is transformed into a low order linear complementarity problem with some low order linear equations and the solution is constructed by the solution of the low order linear complementarity problem and the solutions of these low order linear equations in the transformations. In order to show the accuracy and the effectiveness of the method, the corresponding numerical experiments are performed

Tunable Goos-H\"{a}nchen shift and polarization beam splitter in electro-optic crystals

We have investigated the tunable lateral shift and polarization beam splitting of the transmitted light beam through electro-optic crystals, based on the Pockels effect. The positive and negative lateral shifts could be easily controlled by adjusting the permittivity tensor, which is modulated by the external applied electric field. An alternative way to realize the polarization beam splitter was also proposed by the polarization-dependent lateral shifts. Numerical simulations for Gaussian-shaped incident beam have demonstrated the above theoretical results obtained by stationary phase method. All these phenomena have potential applications in optical devices.Comment: 5 pages, 7 figure

MicroRNA 506 regulates expression of PPAR alpha in hydroxycamptothecin-resistant human colon cancer cells

AbstractChemotherapeutic drug resistance remains a major obstacle to the successful treatment of colon cancer. Here, we show that 77 differentially expressed miRNAs were identified in SW1116/HCPT versus SW1116, and over-expressed miR-506 in SW1116/HCPT cells was validated. Then it was indicated that PPARα is a common target of miR-506 by using a luciferase reporter assay. Our results also demonstrated that cytotoxic ability of HCPT requires the concomitant presence of PPARα, and that loss of PPARα expression imparts resistance to HCPTs anti-tumor effects. All together, our studies indicate that miR-506 over-expression in established HCPT-resistant colon cancer cell line confers resistance to HCPT by inhibiting PPARα expression, then providing a rationale for the development of miRNA-based strategies for reversing resistance in HCPT-resistant colon cancer cells

Expression and activation of Α v Β 3 integrins by SDF-1/CXC12 increases the aggressiveness of prostate cancer cells

BACKGROUND Stromal cell-derived factor-1 (SDF-1 or CXCL12) and CXCR4 are key elements in the metastasis of prostate cancer cells to bone—but the mechanisms as to how it localizes to the marrow remains unclear. METHODS Prostate cancer cell lines were stimulated with SDF-1 and evaluated for alterations in the expression of adhesion molecules using microarrays, FACs, and Western blotting to identify Α v Β 3 receptors. Cell–cell adhesion and invasion assays were used to verify that activation of the receptor is responsive to SDF-1. RESULTS We demonstrate that SDF-1 transiently regulates the number and affinity of Α v Β 3 receptors by prostate cancer cells to enhance their metastatic behavior by increasing adhesiveness and invasiveness. SDF-1 transiently increased the expression of Β 3 receptor subunit and increased its phosphorylation in metastatic but not nonmetastatic cells. CONCLUSIONS The transition from a locally invasive phenotype to a metastatic phenotype may be primed by the elevated expression of Α v Β 3 receptors. Activation and increased expression of Α v Β 3 within SDF-1-rich organs may participate in metastatic localization. Prostate 67:61–73, 2007. © 2006 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55878/1/20500_ftp.pd