对角占优矩阵和块对角占优矩阵的判定

基于α-对角占优矩阵概念,给出了广义严格对角占优矩阵新的判定条件,改进和推广了先前有关文献的相应结果.     

矩阵指数函数的性质

研究了矩阵指数函数在Kronecker积(和),Khatri-Rao积(和),Tracy-Singh 积(和)方面的一些性质,并讨论了矩阵指数函数在矩阵的换位子方面的特殊性质.     

点矩阵式激光喷码

<正> 激光能产生波长和相位相同的相干辐射,其光谱范围一般在紫外光至红外光的光谱内,能在很小的范闰内传递大量的能量。生产激光的方法基本上有几种,但在包装打印上应用的激光,一般会以密封式CO_2作为光源,高     

Expression of extracellular matrix metalloproteinase inducer and matrix metalloproteinases during mouse embryonic development

Mouse embryo implantation is a highly invasive and controlled process that involves remodeling and degradation of the extracellular matrix of the uterus. Matrix metalloproteinases (MMPs) are the main proteinases facilitating this process. Extracellular matrix metalloproteinase inducer (EMMPRIN) can stimulate the production of MMPs and is required for successful implantation in the mouse. The aims of the present study were to examine the expression profiles of mRNA and proteins for EMMPRIN and MMPs in the developing mouse embryo in vitro, and to study whether EMMPRIN protein induces the production of MMPs by mouse blastocysts. EMMPRIN mRNA, detected by RT-PCR, was present at all stages of embryo development from the one-cell to the blastocyst outgrowth. EMMPRIN protein, observed by confocal microscopy, was present on the cell surface at the same stages of development as was the mRNA. Of seven MMPs studied, murine collagenase-like A (Mcol-A), murine collagenase-like B (Mcol-B) and gelatinase A (MMP-2) mRNAs were detected only in blastocyst outgrowths by RT-PCR. Gelatinase B (MMP-9) mRNA was detected both in expanded blastocysts and blastocyst outgrowths. MMP-2 and -9 proteins were detected in the cytoplasm of outgrowing trophoblast cells. Collagenase-2 (MMP-8), collagenase-3 (MMP-13), or stromelysin-1 (MMP-3) mRNAs were not present at any stage of pre- or peri-implantation mouse embryo development. Quantitative RT-PCR analyses showed that recombinant EMMPRIN protein did not stimulate MMP-2 or -9 expression by mouse blastocyst outgrowths. These data suggest that EMMPRIN may regulate physiological functions other than MMP production by mouse embryos during implantation.     

Zinc deprivation inhibits extracellular matrix calcification through decreased synthesis of matrix proteins in osteoblasts

Scope: Zinc is implicated as an activator for bone formation, however, its influence on bone calcification has not been reported. This study examined how zinc regulates the bone matrix calcification in osteoblasts. Methods and Results: Two osteoblastic MC3T3‐E1 cell subclones (SC 4 and SC 24 as high and low osteogenic differentiation, respectively) were cultured in normal osteogenic (OSM), Zinc deficient (Zn–, 1 μM), or adequate (Zn+, 15 μM) media up to 20 days. Cells (SC 4) were also supplemented with (50 μg/mL) or no ascorbic acid (AA) in combination with Zinc treatment. Zn– decreased collagen synthesis and matrix accumulation. Although AA is essential for collagen formation, its supplementation could not compensate for Zinc deficiency‐induced detrimental effects on extracellular matrix mineralization. Zn– also decreased the medium and cell layer alkaline phosphatase ALP activity. This decreased ALP activity might cause the decrease of Pi accumulation in response to Zn–, as measured by von Kossa staining. Ca deposition in cell layers, measured by Alizarin red S staining, was also decreased by Zn^–. Conclusion: Our findings suggest that zinc deprivation inhibits extracellular matrix calcification in osteoblasts by decreasing the synthesis and activity of matrix proteins, type I collagen and ALP, and decreasing Ca and Pi accumulation. Therefore zinc deficiency can be considered as risk factor for poor extracellular matrix calcification.     

拟次酉矩阵及其性质

利用共轭次转置阵和可逆Hermite矩阵给出了拟次酉阵的概念,从而拓广了酉矩阵和拟酉矩阵的概念,并研究了拟次酉阵的若干基本性质及其特征值和特征向量.     

中心自共轭矩阵的一些性质

引入中心自共轭矩阵的定义,给出了中心自共轭矩阵的代数和、转置、积(幂及张量积)以及伴随矩阵也是中心自共轭矩阵的结论.得出当δ(A)＝δ(A-),以及当V是n阶翻矩阵,λ0∈δ(A),0≠X0=(a1,a2,…,an)Y∈Cn,AX0=λX0时,有A-VX0=λX0等论断.     

点阵式激光喷码打印机

<正> 激光科技以永久不变、可靠稳定见称,为使标码永久保存,喷码机生产商不断研究有关技术,现在多米诺公司已将DDC3型点阵式激光喷码机推出市场。 专利系统 节省能源 DDC3型点阵式激光喷码机采用专利的Rainbow~(TM)7根激光管技术进行喷码。传统的激光机大多采用1根激光管,能源消耗量是DDC3型激光机的6～10倍,而且当单管激光机在中速或     

共轭正规矩阵的等价刻画

共轭正规矩阵在酉相合理论中起着重要的作用.利用矩阵对角化、共轭交换、矩阵Toeplitz分解、谱分解及对称酉极分解等矩阵方法,并运用分块矩阵的技巧,讨论了共轭正规矩阵并获得了共轭正规矩阵的若干个等价条件.     

关于Hermite矩阵特征值的不等式

设A是n阶Hermite矩阵,X是nxp矩阵,利用Wely单调定理,通过分类方法,讨论了矩阵X*AX特征值的变分特征;随后通过优化的方法探讨了矩阵A的特征值与矩阵A的元素之间的关系.     

非负矩阵级数收敛性判断

为判断非负矩阵级数收敛性,通过类比非负矩阵级数与正数项级数的一些性质,证明了非负矩阵级数的M判别法、比较原则、比较判别法定理及推论。证明了可以通过布尔矩阵和函数矩阵的反常积分判别非负矩阵级数的收敛性。     

Hankel矩阵的性质及其应用

利用Bez(a,b)矩阵与其中多项式a(λ)的第一友阵适于的缠绕关系,以及a(λ)和b(λ)的变量变换关系给出了Hankel矩阵所满足的几种新型合同关系、缠绕关系;利用Bezout矩阵的Barnett分解以及Bez(a,b)中a(λ)的零点与其第一友阵特征值的一致性,给出了利用Hankel矩阵的非奇异性判定多项式对互素的新方法.     

模糊关系矩阵的若干性质

讨论了模糊关系矩了国的若干与模糊系统稳定性相关的性质;证明了闭环模糊系统矩阵表示的一个充要条件,利用半群理论,给出了模糊关系矩阵序列收敛性的一个简单判别算法。     

广义矩阵迹的贝尔曼不等式

引入了广义矩阵迹τ：Mn(C(Ω））→C（Ω），讨论了在广义矩阵迹下的贝尔曼不等式。证明了C^*-代数Mn(C(Ω))中任意两个正元A，B及A k∈N，有τ（（AB）^k)≤τ（A^kB^k),这便在更一般的框架下给出了Bellman问题的一个肯定问题。同时还利用C^*-代数证明了其它一些相关不等式。     

四元数自共轭矩阵的一个性质

讨论了四元数自共轭矩阵的一个性质,利用该性质把n阶四元数正定(半正定、负定)自共轭矩阵的定义予以简化,得到了与四元数自共轭矩阵的相同结论.     

一类双变量矩阵方程广义自反Ls解的迭代算法

借鉴求线性矩阵方程约束最小二乘（Ls）解的修正共轭梯度法,建立了求特殊类型的双矩阵变量线性矩阵方程的广义自反Ls解的迭代算法,证明了迭代算法的收敛性．利用该算法可在有限步迭代计算后求得矩阵方程的一组广义自反Ls解,选取特殊的初始矩阵时,可求得矩阵方程的极小范数广义自反Ls解．此外,还可求得在该矩阵方程的广义自反Ls解集合中对给定矩阵的最佳逼近．数值算例表明,迭代算法是有效的．     

关于矩阵奇异值的不等式

分析已有的矩阵奇异值不等式和受控理论.利用Weyl定理、k-范数以及弱受控的一些不等式,通过奇异值分解及排序不等式,结合已有结论,得到关于矩阵奇异值的3个不等式结果,即奇异值不等式,受控不等式和酉不变范数不等式.     

矩阵的保半正定性

利用经典的半正定Hermite矩阵的等价条件,讨论了2×2分块矩阵的保半正定性问题.A为2×2半正定Hermite分块矩阵时,则对每一子块分别取迹、行列式、谱范数、秩、数值域后所成矩阵仍为半正定;当A为2×2分块矩阵时,(A)的范数和数值域半径分别不超过(A)的范数和数值域半径.     

利用曲率和相关矩阵的角点检测算法

为提高定位准确性并抑制噪声,利用多方向Gabor滤波器,提出基于曲率和相关矩阵的角点检测方法.首先利用Canny边缘轮廓检测器提取图像的边缘并填充缺口;其次计算边缘像素点的曲率;然后利用多方向Gabor滤波器的虚部对原始图像进行平滑,对每个边缘像素及其邻域构造相关矩阵,利用相关矩阵的归一化特征值计算角点准则函数,将角点准则函数值与边缘像素点的曲率的乘积做为角点测度;最后利用非极大值抑制对候选角点进行筛选.分别在无噪声和噪声情况下进行实验,结果表明,与Harris,CPDA,HeYung角点检测算法相比,该方法可以有效地抑制噪声,平均配准角点数提高了19.6%和25.6%,平均定位误差约降低了6.5%和9.2%.     

Food matrix impact on macronutrients nutritional properties

The food industry is aware of the consumer’s desire to purchase delicious, convenient and nutritious foods. Rapid development of functional foods has induced the food industry to evaluate and revise the composition of their processed foods as well as their processing conditions and methods to improve nutritional and health effects. The addition of new bioactive compounds to a food requires that the bioactive agent is in the active form by the time it reaches the gastrointestinal tract, where it is assimilated. However, the question is whether or not the processes and the composition of traditional foods are carefully balanced to ensure the optimal nutritional properties. This paper aims to review the concepts and facts that are the basis of the new area of research regarding the role of food structure on the nutritional properties of conventional and functional foods. Several original approaches have emerged, bringing together scientists from fields such as food science, nutrition and physiology, which bring enlightening new perspectives to the development of delicious and nutritional foods.