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Estimations of Parametric Functions under a System of Linear Regression Equations with Correlated Errors

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Acta Mathematica Sinica,English Series 2010年第10期26卷 1927-1942页

作者： yong ge tian China Economics and Management Academy Central University of Finance and Economics Beijing 100081 P. R. China

Estimations of parametric functions under a system of linear regression equations with correlated errors across equations involve many complicated operations of matrices and their generalized inverses. In the past several years, a useful tool -- the matrix rank method was utilized to simplify various complicated operations of matrices and their generalized inverses. In this paper, we use the matrix rank method to derive a variety of new algebraic and statistical properties for the best linear unbiased estimators （BLUEs） of parametric functions under the system. In particular, we give the necessary and sufficient conditions for some equalities, additive and block decompositions of BLUEs of parametric functions under the system to hold.

关键词： Linear regression equations SUR model parametric functions estimability BLUE equalities of estimators decompositions of estimators matrix rank method

On Equalities for BLUEs under Misspecified Gauss-Markov Models

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Acta Mathematica Sinica,English Series 2009年第11期25卷 1907-1920页

作者： yong ge tian China Economics and Management Academy Central University of Finance and Economics Beijing 100081 P. R. China

This paper studies relationships between the best linear unbiased estimators （BLUEs） of an estimable parametric functions Kβunder the Gauss-Markov model {y, Xβ, σ^2]E} and its misspecified model {y, X0β,σ^2∑0}. In addition, relationships between BLUEs under a restricted Gauss Markov model and its misspecified model are also investigated.

关键词： original model misspecified model restricted model equality of estimations BLUE matrix rank method

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矩阵广义逆的一个混合反序律

数学学报（中文版） 2009年第1期52卷 197-204页

作者：刘永辉田永革上海金融学院应用数学系上海201209 中央财经大学中国经济与管理研究院北京100081

使用矩阵三元组(A,B,C)的乘积型广义奇异值分解,证明了总是存在广义逆矩阵A^((1,2,3)),B^((1,2))和C^((1,2,4)),使得矩阵乘积ABC的Moore-Penrose逆可以表示成如下形式(ABC)^+=C^((1,2,4))B^((1,2))A^((1,2,3)).所获结果是Wibker,Howe和G... 详细信息

关键词： Moore-Penrose广义逆混合反序律三矩阵的乘积型广义奇异值分解

基于边带限制的梯度矢量流主动轮廓线模型的超声图像分割

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上海交通大学学报 2003年第2期37卷 232-235,240页

作者：严加勇庄天戈上海交通大学生物医学工程系上海200030

主动轮廓线模型是广泛应用于数字图像分析和计算机视觉等领域的一种目标轮廓跟踪算法 ,非常适合于医学图像 (如 CT和 MRI)的处理 .但将这一模型应用于超声图像的分割和目标轮廓的跟踪时 ,由于超声图像不可避免地存在着斑点噪声、弱边界... 详细信息

主动轮廓线模型是广泛应用于数字图像分析和计算机视觉等领域的一种目标轮廓跟踪算法 ,非常适合于医学图像 (如 CT和 MRI)的处理 .但将这一模型应用于超声图像的分割和目标轮廓的跟踪时 ,由于超声图像不可避免地存在着斑点噪声、弱边界和与组织有关的纹理 ,往往使传统主动轮廓模型难以获得满意的轮廓跟踪效果 .为此 ,在梯度矢量流主动轮廓线模型的基础上 ,引入边带限制概念 ,并将该模型应用于超声图像的分割 .实验表明 ,该方法较好地限制了非目标边缘和噪声干扰的影响 ,而且对超声及其序列图像具有较好的分割效果 .

关键词：主动轮廓线模型边带限制超声图像图像分割

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基于动态规划的最优化医学超声图像边缘提取

上海交通大学学报 2002年第7期36卷 970-974页

作者：李斌严加勇庄天戈上海交通大学生物医学工程系上海200030

动态规划 (DP)是一种解决多阶段决策过程最优化的方法 .图像边缘提取时为了使系统输出具有最小的不确定性 ,考虑最优化判据是必要的 .动态规划算法用于图像的边缘检测主要是获得一个图像的最低能量代价阵的过程 ,而图像的边缘对应于最... 详细信息

动态规划 (DP)是一种解决多阶段决策过程最优化的方法 .图像边缘提取时为了使系统输出具有最小的不确定性 ,考虑最优化判据是必要的 .动态规划算法用于图像的边缘检测主要是获得一个图像的最低能量代价阵的过程 ,而图像的边缘对应于最低代价阵中的终止点和起始点之间能量梯度降低最快的路径 ,由此可以由最低代价阵勾勒出需要的边缘 .对于质量较差的图像 ,可以先用梯度算子和一种 LUM滤波器相结合进行预滤波 .实验表明 ,基于该算法用于超声图像的边缘检测可获得全局最优的稳定的边缘线。

关键词：边缘检测动态规划边缘增强图像分割最优化算法医学超声图像边缘提取

序列超声图像边缘检测与跟踪的改进Snake模型

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上海交通大学学报 2003年第z1期37卷 106-108,117页

作者：严加勇庄天戈上海交通大学生物医学工程系上海200030

提出了一种序列超声图像边缘检测与跟踪的离散动态模型.在基于动态规划的Snake模型中,引入目标边缘的形状信息改进了内部能量约束形式;充分利用序列图像相邻层间的灰度相关信息弥补了传统Snake模型中图像梯度能量对噪声敏感的不足.实验... 详细信息

提出了一种序列超声图像边缘检测与跟踪的离散动态模型.在基于动态规划的Snake模型中,引入目标边缘的形状信息改进了内部能量约束形式;充分利用序列图像相邻层间的灰度相关信息弥补了传统Snake模型中图像梯度能量对噪声敏感的不足.实验结果表明,改进的Snake模型仅需少量的用户交互就能快速、准确地从超声序列图像中检测、跟踪出目标物体的边缘,在医学图像分析中具有一定的实用价值.

关键词： Snake模型动态规划超声图像边缘检测相关性信息

Enhancing m^(6)A modification in the motor cortex facilitates corticospinal tract remodeling after spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1749-1763页

作者： tian Qin Yuxin Jin Yiming Qin Feifei Yuan Hongbin Lu Jianzhong Hu yong Cao Chengjun Li Department of Spine Surgery and Orthopedics Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan ProvinceChangshaHunan ProvinceChina National Clinical Research Center for geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Department of Sports Medicine Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.

关键词： corticospinal tract remodeling epigenetic regulations locomotor cortex m^(6)A modification methyltransferase 14 protein(METTL14) mitogen-activated protein kinase neural regeneration spinal cord injury syringin TRIB2

基于SBAS-InSAR和光学遥感的天津市北部山区潜在滑坡识别研究

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灾害学 2025年第1期40卷 30-35页

作者：王勇邢振涛李锁闫勇司甜天津城建大学地质与测绘学院天津300384 天津市地质工程勘测设计院有限公司天津300191

以天津市北部山区为研究对象,开展潜在滑坡识别研究,利用差分干涉测量短基线集时序分析技术(SBAS-InSAR)处理2018-01—2022-08的56景Sentinel-1A数据,并结合2018—2022年的Landsat8光学遥感影像,分析形变与光学遥感影像特征以及NDVI,筛... 详细信息

以天津市北部山区为研究对象,开展潜在滑坡识别研究,利用差分干涉测量短基线集时序分析技术(SBAS-InSAR)处理2018-01—2022-08的56景Sentinel-1A数据,并结合2018—2022年的Landsat8光学遥感影像,分析形变与光学遥感影像特征以及NDVI,筛选出潜在滑坡区域。研究结果表明:基于SBAS-InSAR技术识别的天津北部山区的形变较大区域有20处,使用光学遥感影像结合各发育环境要素进行处理确定的区域有19处,其中5处经两种技术确认为滑坡隐患,通过对该5处沉降信息进行识别分析,该5处区域最大年形变速率可达-12 mm/a,需要进行重点监测预警,使用两种技术结合对滑坡隐患区域进行识别可以有效地提高识别准确度,为天津北部山区灾害监测提供新的方式。

关键词：潜在滑坡 SBAS-InSAR 光学遥感影像天津市北部山区

Co-assembly of FeTPP@Fe_(3)O_(4) nanoparticles with photo-enhanced catalytic activity for synergistic tumor therapy

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Nano Research 2022年第10期15卷 9114-9124页

作者： tian tian Jianshuai Bao Jinghan Wang Jiefei Wang Yan ge Zengyin Li Shanqing Gao Zhongqi You Xiaoyan Yang yong Zhong Feng Bai Key Laboratory for Special Functional Materials of Ministry of Education National&Local Joint Engineering Research Center for High-efficiency Display and Lighting TechnologySchool of Materials Science and EngineeringCollaborative Innovation Center of Nano Functional Materials and ApplicationsHenan UniversityKaifeng 475004China Henan-Macquarie University Joint Centre for Biomedical Innovation School of Life SciencesHenan UniversityKaifeng 475004China

Chemodynamic therapy(CDT)offers a promising alternative to conventional cancer ***,the limited acidity and H_(2)O_(2) concentration in tumor microenvironment(TME)severely impair the anticancer effects of *** this study,we report a microemulsion-assisted coassembly method to prepare iron(III)tetraphenylporphyrin(FeTPP)and magnetic(Fe_(3)O_(4))nanocomposite material(FeTPP@Fe_(3)O_(4)),using photoactive FeTPP and Fe_(3)O_(4) nanocrystals as building *** selfassembling nature of FeTPP results in disordered aggregation and fluorescence quenching,leading to a high light-to-heat conversion ***,the photo-thermal effect enhances the catalytic decomposition of hydrogen peroxide(H_(2)O_(2))in the Fenton reaction on Fe_(3)O_(4) nanocrystals to generate highly toxic hydroxyl radicals(·OH)to destroy cancer *** cascade reaction produces a synergistic therapeutic effect between CDT and photothermal therapy(PTT),which significantly amplifies the therapeutic effect and enhances the treatment outcome of cancer *** highly efficient tumor catalytic therapy in vivo results confirmed that this nanomedicine treatment is an excellent biocompatible catalytic nanomedicine therapy achieved through a photo-enhanced Fenton reaction activity approach.

关键词： porphyrin photo-enhanced nanocatalyst synergistic therapy