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Localized Vibrational Modes of Excitation in Electroluminescent Polymers

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Chinese Physics Letters 1999年第11期16卷 836-837页

作者： JIANG Hao xu xiao-hua SUN Xin KYonemitsu T.D.Lee Laboratory and Department of Physics Fudan UniversityShanghai 200433 National Laboratory of Infrared Physics Shanghai Institute for Technical PhysicsShanghai 200083 Institute for Molecular Science Okazaki 444-8585Japan

The localized vibrational modes of exciton and polaron are investigated, and the results show that the frequencies of the three even parity modes of exciton are very different from those of polaron. For the exciton, three modes are distinctly separated;but, for the polaron, two modes with higher frequencies are close to each other, Then, it is possible to distinguish exciton from polaron by watching their Roman spectra. Therefore, the localized mode may be used to specify the exciton and polaron in the electroluminesent polymers.

关键词： spectra. polaron vibrational

Collagenous gastritis in a young Chinese woman:A case report

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World Journal of Gastroenterology 2022年第41期28卷 5993-6001页

作者： Qing-hua Zheng Jie Hu xiao-Yuan Yi xu-hua xiao Li-Na Zhou Bin Li xiao-Tong Bo Department of Gastroenterology Affiliated Hospital of Guilin Medical UniversityGuilin 541001Guangxi ProvinceChina

BACKGROUND Collagenous gastritis(CG) is a rare condition whose pathogenesis may be related to immune abnormalities. We report a case of CG from *** SUMMARY A 24-year-old woman presented with recurrent abdominal distension and discomfort for 3 mo. Upper gastrointestinal endoscopy found diffuse nodular elevation-depression changes in the mucosa of the entire gastric *** ultrasound showed predominant involvement of the lamina propria and submucosa, and computed tomography imaging showed mild enhancement of the gastric wall. Pathological histology revealed that the thickness of the subepithelial collagen band was about 40 μm, and the Masson trichrome staining result was positive and the Congo red staining result was negative. This case is consistent with the child-adolescent type of *** Serum pepsinogen Ⅰ, pepsinogen Ⅱ, pepsinogen Ⅰ/Ⅱ ratio, and gastrin-17 may be potential non-invasive monitoring markers. Currently, treatments for CG vary,and the likely prognosis is unknown. Individual cases of gastric cancer in patients with CG have been reported.

关键词： Endoscopy Endoscopic ultrasound Collagenous gastritis Hematoxylin and eosin staining Masson’s trichrome staining Case report

Synthesis and Biological Activity of Novel Spin Labeled Derivatives of 4′-Demethyl-4-deoxypodophyllotoxin

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Chemical Research in Chinese Universities 2010年第5期26卷 753-756页

作者： xu Jing SUN xiao-hua ZHANG Jia-qiang ZHANG Zhi-wei TIAN xuan State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 P. R. China

Seven novel spin labeled derivatives of 4＇-demethyl-4-deoxypodophyllotoxin with nitroxyl radi- cals（TMHPO and TMPRO） were prepared and their cytotoxic and antioxidative activities were tested. Their cytotoxic activities were tested against two tumor cell lines（A-549 and HL-60） in vitro. Among them, five compounds show higher inhibition activity against A-549 cells compared with the clinical drug VP-16（2） and parent compound 4＇-demethyl-4-deoxypodophyllotoxin（DDPT, 6）. Compounds 8, 10 and 13 show excellent inhibition activity against HL-60 cells. Furthermore, the antioxidative activities of them were tested. All the seven spin labeled compounds show stronger antioxidative activity compared with VP-16（2） and DDPT（6）. The partition coefficients P of these derivatives were determined.

关键词： 4'-Demethyl-4-deoxypodophyllotoxin Nitroxyl radical Antiturnor activity Antioxidative activity

Two Brominated-sesquiterpene from Alga Laurencia Majuscula

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Chemical Research in Chinese Universities 2002年第2期18卷 226-227页

作者： xu xiao-hua YAO Guang-min LU Jian-hua LI Yan-ming CHANG Jiang-lin KONG Chui-hua Institute of Elemento-Organic Chemistry Nankai UniversityTianjin 300071P.R.China Institute of Tropic and Subtropical Ecology South China Agriculture UniversityGuangzhou 510642P.R.China

Two brominated sesquiterpenes were isolated from the Alga Laurencia majuscula collected from the Xisha Islands in the South China Sea. Compound 1 was first reported, and determined, on spectral evidence, to be 8 bromo... 详细信息

关键词： Laurencia majuscula Brominated sesquiterpene Spectral analysis

Novel distribution pattern of fibrinolytic components in rabbit tissues extract: a preliminary study

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第8期8卷 570-574页

作者： LU Xing-guo WU Xian-guo xu xiao-hua GONG xu-bo ZHOU xuan xu Gen-bo ZHU Lei ZHAO xiao-ying Department of Haematology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Department of Clinical Laboratory Diagnosis the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

Objective: The purpose of this work was to investigate the distribution pattern of fibrinolytic factors and their inhibitors in rabbit tissues. Methods: The components of the fibrinolytic system in extracts from a variety of rabbit tissues, including tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), plasminogen (Plg), plasmin (Pl) and α2 plasmin inhibitor (α2PI), were determined by colorimetric assay. Results: The tissue extracts in renal, small intestine, lung, brain and spleen demonstrated strong fibrinolytic function, in which high activity of tPA, Plg and Pl was manifested; whereas in skeletal muscle, tongue and stomach, higher activity of PAI-1 and α2PI showed obviously. Also excellent linear correlations were found between levels of tPA and PAI-1, Pl and α2PI, Plg and Pl. In related tissues, renal cortex and renal marrow showed distinctly higher activity of tPA and lower activity of PAI-1, with the levels of Plg and Pl in renal cortex being higher than those in renal marrow, where the α2PI level was higher than that in renal cortex. Similarly, the levels of tPA, Plg and Pl in small intestine were higher than those in large intestine, but with respect to PAI-1 and α2PI, the matter was reverse. In addition, the fibrinolytic activity in muscle tissue was lower, however, the levels of tPA, Plg, and Pl in cardiac muscle were obviously higher than those in skeletal muscles, and the levels of PAI-1 and α2PI were significantly lower than those in skeletal muscle. Conclusion: Our data demonstrate that a remarkable difference of the fibrinolytic patterns exists in rabbit tissues, which has probable profound significance in understanding the relationship between the function of haemostasis or thrombosis and the physiologic function in tissues.

关键词： Tissue extract Fibrinolytic factors Fibrinolytic inhibitors

利用COSMIC掩星弯曲角数据分析中国区域对流层顶结构变化

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地球物理学报 2013年第8期56卷 2531-2541页

作者：徐晓华高攀张小红武汉大学测绘学院武汉430079

对流层顶是地球大气的一个最基本的结构特征,对流层与平流层通过对流层顶交换气团、水汽、微量气体、能量等.对流层顶结构变化与气候变化密切相连.本文采用掩星弯曲角自然对数协方差变换法确定对流层顶,利用气象、电离层与气候星座观测... 详细信息

对流层顶是地球大气的一个最基本的结构特征,对流层与平流层通过对流层顶交换气团、水汽、微量气体、能量等.对流层顶结构变化与气候变化密切相连.本文采用掩星弯曲角自然对数协方差变换法确定对流层顶,利用气象、电离层与气候星座观测系统(Constellation Observing System for Meteorology,Ionosphere and Climate,COSMIC)2007年1月至2011年12月共5年的掩星观测数据分析了中国区域对流层顶高度、温度、气压等参数随经度、纬度、时间变化的特征.采用2°×2°网格法,把包括中国在内的16°N—54°N、72°E—136°E区域共分成19×32个格网单元,然后计算每个格网单元内对流层顶高度、温度、气压的平均值,结果表明对流层顶参数呈明显的纬度分带分布特征.计算每个格网单元内对流层顶参数季节平均值,结果显示对流层顶高度和气压具有明显的季节性变化特征.采用中位数斜率回归法分析对流层顶参数年平均值,发现在研究时段内中国区域对流层顶高度平均每年降低8m.

关键词：对流层顶 COSMIC GPS无线电掩星弯曲角

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一种自适应的蚂蚁聚类算法

软件学报 2006年第9期17卷 1884-1889页

作者：徐晓华陈崚南京航空航天大学信息科学与技术学院江苏南京210016 扬州大学计算机科学与工程系

受蚂蚁分巢居住行为的启发,提出一种人工蚂蚁运动(antmovement,简称AM)模型和在此模型上的一个自适应的蚂蚁聚类算法(adaptiveantclustering,简称AAC).将人工蚂蚁看成一个行为简单的Agent,代表一个数据对象.在AM中,人工蚂蚁有睡眠和活... 详细信息

受蚂蚁分巢居住行为的启发,提出一种人工蚂蚁运动(antmovement,简称AM)模型和在此模型上的一个自适应的蚂蚁聚类算法(adaptiveantclustering,简称AAC).将人工蚂蚁看成一个行为简单的Agent,代表一个数据对象.在AM中,人工蚂蚁有睡眠和活跃两种状态.在AAC算法中,定义了一个适应度函数用来衡量蚂蚁与其邻居的相似程度.人工蚂蚁通过其适应度和激活概率函数来决定处于活跃态或者睡眠态.整个蚂蚁群体在移动中动态地、自适应地、自组织地形成多个独立的子群体,使不同类别的蚂蚁之间相互分离;而同类的蚂蚁之间高度紧密地排列,从而形成聚类.提出了对参数的自适应的更新方法,使得人工蚂蚁的移动仅仅使用少量的局部信息,这对加快聚类速度和提高聚类质量有非常显著的效果.模拟实验充分显示出,该蚂蚁聚类算法与BM和LF算法相比,在模型上更直观,操作上更简单,可自适应地修改参数,对参数的限制少,计算成本较小,聚类质量高,具有速度快、高效、自组织性和鲁棒性的优点,适用于解决高维、复杂的聚类问题.

关键词：群体智能蚁群聚类

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潜在属性空间树分类器

软件学报 2009年第7期20卷 1735-1745页

作者：何萍徐晓华陈崚南京航空航天大学信息科学与技术学院计算机科学与工程系江苏南京210016 扬州大学信息工程学院计算机科学与工程系江苏扬州225009

提出一种潜在属性空间树分类器(latent attribute space tree classifier,简称LAST)框架,通过将原属性空间变换到更容易分离数据或更符合决策树分类特点的潜在属性空间,突破传统决策树算法的决策面局限,改善树分类器的泛化性能.在LAST... 详细信息

提出一种潜在属性空间树分类器(latent attribute space tree classifier,简称LAST)框架,通过将原属性空间变换到更容易分离数据或更符合决策树分类特点的潜在属性空间,突破传统决策树算法的决策面局限,改善树分类器的泛化性能.在LAST框架下,提出了两种奇异值分解斜决策树(SVD(singular value decomposition)oblique decision tree,简称SODT)算法,通过对全局或局部数据进行奇异值分解,构建正交的潜在属性空间,然后在潜在属性空间内构建传统的单变量决策树或树节点,从而间接获得原空间内近似最优的斜决策树.SODT算法既能够处理整体数据与局部数据分布相同或不同的数据集,又可以充分利用有标签和无标签数据的结构信息,分类结果不受样本随机重排的影响,而且时间复杂度还与单变量决策树算法相同.在复杂数据集上的实验结果表明,与传统的单变量决策树算法和其他斜决策树算法相比,SODT算法的分类准确率更高,构建的决策树大小更稳定,整体分类性能更鲁棒,决策树构建时间与C4.5算法相近,而远小于其他斜决策树算法.

关键词：分类决策树潜在属性空间奇异值分解

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监督式谱空间分类器

软件学报 2012年第4期23卷 748-764页

作者：何萍徐晓华陈崚南京航空航天大学计算机科学与技术学院江苏南京210016 扬州大学信息工程学院计算机系江苏扬州225009

提出了一种非线性的监督式谱空间分类器(supervised spectral space classifier,简称S3C).S3C首先将输入数据映射到融合了训练数据判别信息的低维监督式谱空间中,然后在该监督式谱空间中构造最大化间隔的最优分割超平面,并把测试数据以... 详细信息

提出了一种非线性的监督式谱空间分类器(supervised spectral space classifier,简称S3C).S3C首先将输入数据映射到融合了训练数据判别信息的低维监督式谱空间中,然后在该监督式谱空间中构造最大化间隔的最优分割超平面,并把测试数据以无监督的方式也映射到与训练数据相同的新特征空间中,最后,直接应用之前构建的分类超平面对映射后的测试数据进行分类.由于S3C使研究者可以直观地观察到变化后的特征空间和映射后的数据,因此有利于对算法的评价和参数的选择.在S3C的基础上,进一步提出了一种监督式谱空间分类器的改进算法(supervised spectral space transformation,简称S3T).S3T通过采用线性子空间变换和强迫一致的方法,将映射到监督式谱空间内的数据再变换到指定的类别指示空间中去,从而获得关于测试数据的类别指示矩阵,并在此基础上对其进行分类.S3T不仅保留了S3C算法的各项优点,而且还可以用于直接处理多分类问题,抗噪声能力更强,性能更加鲁棒.在人工数据集和真实数据集上的大量实验结果显示,S3C和S3T与其他多种著名分类器相比,具有更加优越的分类性能.

关键词：分类谱方法维数约减流形映射监督式谱空间