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Microarray profiles on age-related genes in the earlier postnatal rat visual cortex

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Chinese Medical Journal 2011年第10期124卷 1545-1550页

作者： YANG liu NIE Yu-hong zhou li-hua liN Shao-chun WU Kai-li Department of Ophthalmology Beijing Tiantan Hospital Capital Medical University Beijingt00050 China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou Guangdong 510060 China Department of Anatomy Zhongshan Medical College Sun Yat-sen University Guangzhou Guangdong 510060 China Department of Ophthalmology Renmin Hospital of Wuhan University Wuhan Hubei 430060 China

Background Accumulating evidence indicates that both innate and adaptive mechanisms are responsible for the postnatal development of the mammalian visual cortex. Most of the studies, including gene expression analysis, were performed on the visual cortex during the critical period; few efforts were made to elucidate the molecular changes in the visual cortex during much earlier postnatal stages. The current study aimed to gain a general insight into the molecular mechanisms in the developmental process of the rat visual cortex using microarray to display the gene expression profiles of the visual cortex on postnatal *** All age-matched Sprague-Dawley rats in various groups including postnatal day 0 （PO, n=20）, day 10 （P10,n=15）, day 20 （P20, n=15） and day 45 （P45, n=10） were sacrificed respectively. Fresh visual cortex from the binocular area （Area 17） was dissected for extraction of total RNA for microarray analyses. Taking advantage of annotation information from the gene ontology and pathway database, the gene expression profiles were systematically and globally *** Of the 31 042 gene sequences represented on the rat expression microarray, more than 4000 of the transcripts significantly altered at days 45,20 or 10 compared to day 0. The most obvious alteration of gene expression occurred in the first ten days of the postnatal period and the genomic activities of the visual cortex maintained a high level from birth to day 45. Compared to the gene expression at birth, there were 2630 changed transcripts that shared in three postnatal *** up-regulated genes in most signaling pathways were more than those of the down-regulated *** Analyzing gene expression patterns, we provide a detailed insight into the molecular organization of the developing visual cortex in the earlier postnatal rat. The most obvious alteration of gene expression in visual cortex occurred in the first ten days. Our data were a basis to identify new rele

关键词： microarray analysis earlier postnatal development visual cortex rat

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共轭梯度型支撑向量机

模式识别与人工智能 2006年第2期19卷 129-136页

作者：周水生周利华西安电子科技大学理学院

求解支撑向量机的二次规划有不同的变形.对于线性问题.从一个变形出发,利用 Lagrangian 对偶技巧,将特征空间的高维二次规划问题转化为输入空间的低维无约束、可微凸的对偶规划.针对目标函数的分片二次特征,结合快速精确的一维搜索技术... 详细信息

求解支撑向量机的二次规划有不同的变形.对于线性问题.从一个变形出发,利用 Lagrangian 对偶技巧,将特征空间的高维二次规划问题转化为输入空间的低维无约束、可微凸的对偶规划.针对目标函数的分片二次特征,结合快速精确的一维搜索技术,提出共轭梯度型支撑向量机来求解该问题.利用 Cholesky 分解或非完全(in-complete)Cholesky 分解方法分解核矩阵,在算法复杂度增加很少的条件下可实现基于核函数的非线性分类.该算法可以在普通计算机上快速求解上百万规模的线性训练问题和较大规模的非线性训练问题.大量数据实验和复杂度分析表明,该算法与同类算法如 ASVM、LSVM 相比是有效的.

关键词：支撑向量机共轭梯度法 Lagrangian对偶核函数

DCT压缩域中基于纹理和形状的图像检索算法

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西安电子科技大学学报 2007年第3期34卷 402-408页

作者：赵珊周利华西安电子科技大学多媒体研究所陕西西安710071

在对以往DCT压缩域的图像检索算法研究的基础上,将DCT块及其系数的空间分布信息引入特征提取算法,提出了一种压缩域中结合纹理和形状信息的图像检索算法.根据DCT块的复杂度及块内系数的空间分布,构造了加权复杂度直方图来表述图像的纹... 详细信息

在对以往DCT压缩域的图像检索算法研究的基础上,将DCT块及其系数的空间分布信息引入特征提取算法,提出了一种压缩域中结合纹理和形状信息的图像检索算法.根据DCT块的复杂度及块内系数的空间分布,构造了加权复杂度直方图来表述图像的纹理信息;同时,根据DCT块系数的取值将其划分为不同的边缘类型,并采用边缘空间分布特征来描述图像的形状信息.该算法不仅考虑了DCT块的统计分布,又考虑了块内系数的空间分布,在一定程度上避免了由于DCT块统计分布信息相同而空间分布信息不同而造成的误检漏检情况.实验结果表明,该算法具有较好的检索结果.

关键词：基于内容的图像检索离散余弦变换加权复杂度直方图边缘空间分布特征

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试论矿山灾害学的建立及研究途径

湘潭矿业学院学报 2000年第4期15卷 1-6页

作者：周利华湘潭工学院资源工程系湖南湘潭411201

当前矿山灾害的现状决定了矿山灾害学的形成矿山灾害学乃是一适应未来矿山企业生存和发展的的新命题矿山灾害学的研究要从整个矿区大环境、大安全的角度出发 ,实行多学科、多理论的交叉渗透与此同时 ,还必须大力开展多层次、多领... 详细信息

当前矿山灾害的现状决定了矿山灾害学的形成矿山灾害学乃是一适应未来矿山企业生存和发展的的新命题矿山灾害学的研究要从整个矿区大环境、大安全的角度出发 ,实行多学科、多理论的交叉渗透与此同时 ,还必须大力开展多层次、多领域、多方位的国际协作这样才能全面、系统、综合地发展矿山灾害学理论参

关键词：矿山安全矿山灾害学安全工程学事故预测预防原理

Anti-oxidation of Tanshinone Ⅱ_A and Prohibitin on Cardiomyocytes

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Chinese Herbal Medicines 2010年第3期2卷 204-210页

作者： YANG Ping, JIA Yu-hua, li Jie, zhou Feng-hua, li li-jun Southern Medical University, Guangzhou 510515, China Southern Medical University Guangzhou 510515China

Objective To investigate the anti-apoptotic mechanism of tanshinone ⅡA and the function of prohibitin (PHB) on myocardial cells apoptosis induced by hydrogen peroxide (H2O2). Methods Myocardial cells were primary cultured neonate rat were cultured in medium with 200 μmol/L H2O2, and the medium was supplemented with tanshinone ⅡA (1 × 10-4 mol/L) in advance for 24 h. PHB in myocardial cells was knocked down by RNA interference, and the expression level of PHB was determined by Western blotting analysis. Flow cytometric analysis was used to detect apoptosis rate, intracellular calcium concentration ([Ca2+]i), and mitochondrial membrane potential (MMP). Results H2O2-mediated cell apoptosis resulted in activation of PHB, increasing of [Ca2+]i, and decreasing of MMP. Tanshinone ⅡA profoundly inhibited myocardial cell apoptosis induced by H2O2, decreased [Ca2+]i, and increased MMP. Specific silence of PHB by siRNA down-regulated the expression level of PHB, increased apoptosis rate and [Ca2+]i, and decreased MMP. Conclusion The results demonstrate that tanshinone ⅡA could attenuate apoptosis induced by H2O2, and the activation of PHB induced by H2O2 is the major regulatory pathway of cyto-protective gene expression against oxidative stress.

关键词： calcium overload myocardial cell oxidative stress prohibitin tanshinone ⅡA

Design and Performance of an AlGaN-Based p-i-n Ultraviolet Photodetector

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Journal of Electronic Science and Technology of China 2009年第3期7卷 272-276页

作者： Xing-li zhou Mo-hua Yang Jiang-Feng Du State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu 610054 China

An AIGaN-based back-illuminated ultraviolet p-i-n detector is designed and its performance is analysed both simulately and experimentally. The width of p- and i-regions has been optimized to the best theoretic values. It is indicated that the changing of responsivity with increase of bias can not be attributed to the expansion of depletion layer as it is believed, but to two reasons： 1） the effect of GaN/AlGaN heterojunction barrier to block the electrons decreases with higher bias and 2） the recombination rate of excess carriers decreases due to the building up of an electric field in depletion region. At zero bias, the simulated responsivity reaches its maximum of 0.12 A/W with quantum efficiency of 55.1%. The measured peak responsivity is more than 0.09 A/W with quantum efficiency greater than 41.6%. The experimental data are almost consistent with the results of the simulation.

关键词： Hetero-junction barrier recombination rate responsivity ultraviolet photodetector

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li Zhen Ma Jin-hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

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基于WOWA-FCM的复合攻击检测模型

四川大学学报（工程科学版） 2008年第1期40卷 122-126页

作者：吕镇邦周利华西安电子科技大学计算机网络与信息安全教育部重点实验室陕西西安710071

为有效处理复合攻击检测中的诸多不确定性及复杂性因素,提出了基于WOWA-FCM的复合攻击检测模型。WOWA-FCM检测模型从攻击意图分析的角度,利用模糊认知图(Fuzzy Cognitive Maps,FCM)对初级入侵警报进行因果关联;并结合脆弱性知识与系统... 详细信息

为有效处理复合攻击检测中的诸多不确定性及复杂性因素,提出了基于WOWA-FCM的复合攻击检测模型。WOWA-FCM检测模型从攻击意图分析的角度,利用模糊认知图(Fuzzy Cognitive Maps,FCM)对初级入侵警报进行因果关联;并结合脆弱性知识与系统配置信息,利用WOWA(Weighted Ordered Weighted Averaging)算子融合关联数据。WOWA-FCM检测模型不仅能识别复合攻击各个阶段、构建完整的攻击视图,并且能动态地评判攻击进度和目标系统的安全状态。WOWA-FCM模型简化了传统的复合攻击检测过程,并具有较强的适应性。MstreamDDoS攻击检测实验证明了方法的有效性。

关键词：复合攻击模糊认知图入侵检测 WOWA算子警报关联

Recent development in electrode design for wide-temperature supercapacitors

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Science China Chemistry 2025年第1期68卷 96-117页

作者： Jianhong liu Qiang zhou Yuxiao lin Xinsheng Zhao Guangmin zhou Xiaoxiao li School of Physics and Electronic Engineering Jiangsu Normal University Tsinghua-Berkeley Shenzhen Institute & Tsinghua Shenzhen International Graduate School Tsinghua University

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature supercapacitors(SCs). The active electrode is one of the most important parts of SC, which is directly related to the energy density,power transmission and long-term cyclability of the device in the wide-temperature environment. Compared with the SC electrodes aimed for room-temperature application, the SC electrodes for operating at wide-temperature scene often face greater challenges. In this review, the main challenges of SC electrodes under various temperature conditions, including low, high and cross-fade temperatures, are summarized. The relevant performance decay and failure mechanisms of wide-temperature SC electrodes are analyzed. In addition, this review deals with the recent studies and developments in robust wide-temperature SC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active materials. Finally, the future directions for exploring reliable wide-temperature SCs are also proposed.

关键词： supercapacitor wide-temperature electrode design active materials