Expression of matrix metalloproteinase-9 in nasopharyngeal carcinoma and association with Epstein-Barr virus infection

Objective: To evaluate the expression of matrix metalloproteinase-9 (MMP9) in nasopharyngeal carcinoma and the association between MMP9 and Epstein-Barr virus infection. Methods: The MMP9 expression was studied by immunohistochemical analysis; and Epstein-Barr virus encoded small nuclear mRNA-1 (EBER-1) produced by in situ hybridization were examined in 41 nasopharyngeal carcinoma sections, and the relation between them, and the associations of MMP9 with clinical features were statistically analyzed. Results: Positive expression rate of MMP9 was 73.17%. The expression of MMP9 showed significant positive correlation with the expression of EBER- 1 (γ=0.483, P=0.001). There was significant association of MMP9 expression with lymph nodes metastasis and clinical stage (P＜0.001), non-significant association with age, gender, pathological classification and T classification. Conclusions: The highly pronounced expression of MMP9 is associated with cervical lymph nodes metastasis. Epstein-Barr virus can enhance NPC metastasis by up-regulating the expression of MMP9.     

Passive fuzzy controller design for nonlinear systems with multiplicative noises

This paper proposes a passive fuzzy controller design methodology for nonlinear system with multiplicative noises. Applying the Itô's formula and the sense of mean square, the sufficient conditions are developed to analyze the stability and to design the controller for stochastic nonlinear systems which are represented by the Takagi-Sugeno (T-S) fuzzy models. The sufficient conditions derived in this paper belong to the Linear Matrix Inequality (LMI) forms which can be solved by the convex optimal programming algorithm. Besides, the passivity theory is applied to discuss the effect of external disturbance on system. Finally, some numerical simulation examples are provided to demonstrate the applications of the proposed fuzzy controller design technique.     

Jacobi正交多项式的一些性质

Jacobi正交多项式被广泛地应用于Jacobi谱方法的数值分析中,它的性质对于误差分析极其重要．通过总结Jacobi正交多项式的一些性质,给出了它的一些新性质．     

关于非奇H矩阵某些迭代的谱半径

当系数矩阵A是非奇H矩阵时,通过分析求解线性方程组的雅可比、高斯塞德尔和超松弛方法的迭代矩阵特征值,得出相关谱半径的性质,进而将雅可比迭代和高斯塞德尔迭代收敛的充分条件由A为严格对角占优矩阵放宽到A为非奇H矩阵,同时证明了此时低松弛迭代也是收敛的．     

求解奇异线性方程组的双逐次投影法

用双逐次投影迭代法来求解奇异线性方程组,当线性方程组的系数矩阵是对称半正定时,给出了不同情形时有关参量的选取以及相应的算法,并就收敛结果分别与雅可比迭代法和Gauss-Seidel迭代法进行了比较,数值结果表明,该方法对求解奇异线性方程组是很有效的.     

Using diagrams as tools for the solution of non-routine mathematical problems

The Mathematics education community has long recognized the importance of diagrams in the solution of mathematical problems. Particularly, it is stated that diagrams facilitate the solution of mathematical problems because they represent problems’ structure and information (Novick & Hurley, 2001; Diezmann, 2005). Novick and Hurley were the first to introduce three well-defined types of diagrams, that is, network, hierarchy, and matrix, which represent different problematic situations. In the present study, we investigated the effects of these types of diagrams in non-routine mathematical problem solving by contrasting students’ abilities to solve problems with and without the presence of diagrams. Structural equation modeling affirmed the existence of two first-order factors indicating the differential effects of the problems’ representation, i.e., text with diagrams and without diagrams, and a second-order factor representing general non-routine problem solving ability in mathematics. Implicative analysis showed the influence of the presence of diagrams in the problems’ hierarchical ordering. Furthermore, results provided support for other studies (e.g. Diezman & English, 2001) which documented some students’ difficulties to use diagrams efficiently for the solution of problems. We discuss the findings and provide suggestions for the efficient use of diagrams in the problem solving situation.     

氢原子第四激发态（n=5）能级简并的解除

用简并微扰论研究氢原子第四激发态（n=5）在正交非均匀外电场中的能级分裂情况.并介绍高阶方阵本征问题的Jacobi解法.     

高次非线性薛定谔微分方程的新精确解

主要利用直接截断法来讨论非线性薛定谔微分方程： iu1＋uxx＋α0｜u｜^2u＋i[γ1uxx＋γ2｜u｜^2ux＋γ3（｜u｜^2）xu]=0 的精确解．借助于符号计算软件Maple,得到了此方程一些新的含Jacobi椭圆函数的精确解。     

Legendre符号及Gauss二次互反律的证明

介绍了Legendre符号的应用,给出了初等数论中Gauss二次互反律的一个证明,证明中的个别地方在常见文献中不曾见过,并将Legendre符号与Jacobi符号在计算上给予了比较和总结。     

A simplified MMSE-based iterative receiver for MIMO systems

A simplified minimum mean square error （MMSE） detector is proposed for joint detection and decoding of multiple-input multiple-output （MIMO） systems. The matrix inversion lemma and the singular value decomposition （SVD） of the channel matrix are used to simplify the computation of the coefficient of the MMSE filter. Compared to the original MMSE detector, the proposed detector has a much lower computational complexity with only a marginal performance loss. The proposed detector can also be applied to MIMO systems with high order modulations.