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The circularly propagating pattern of the low-frequencyfluctuations of monthly MSL in the tropical PacificOcean and its correlation with El Nino

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Acta Oceanologica Sinica 1992年第2期11卷 205-218页

作者： yu Jiye, chen Shangjil and fang Xinhua

The long-term time series analysis of the SST (sea surface temperature) in the Eastern Equatorial Pacific Ocean and the monthly MSL (mean sea level) in the tropical Pacific Ocean is conducted. Their quasiperiodic and low-frequency oscillation features are revealed. The significant periods of low-frequency fluctuations for monthly MSL in the area of 20°N-20° S are between 43. 5 months and 50. 0 months, approximating closely to 47. 6 months which is the significant period of SST in the Eastern Equatorial Pacific Ocean. From the results of space-spectral analysis, the low-frequency fluctations of monthly MSL in the tropical Pacific Ocean appear to have a anticlockwise circularly-propagating pattern, which is, the Eastern Pacific Ocean (off-shore of Mexico) →the area of NEC (North Equatorial Current) →the Western Equatorial Pacific Ocean→the area of NECC (North Equatorial Counter-Current)→the Eastern Equatorial Pacific Ocean. The phases of the pattern correspond to those of El Nino cycle. On the basis of the above results,a basic model is established with stepwise-regression method, which can forecast El Nino events by the variations of monthly MSL at a few stations in the tropical Pacific Ocean 4 months ahead. The correlation coefficient between the forecasted series and the observed one is 0. 89.

关键词： MSL The circularly propagating pattern of the low-frequencyfluctuations of monthly MSL in the tropical PacificOcean and its correlation with El Nino Nino El

A Geometric Robust Watermarking Algorithm Based on DWT-DCT and Zernike Moments

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Wuhan University Journal of Natural Sciences 2008年第6期13卷 753-758页

作者： chen yu QU fang HU Jianbin chen Zhong School of Electronics Engineering and Computer Science Peking University/Key Laboratory of High Confidence Software Technologies of Ministry of Education Beijing 100871 China

This paper proposed a novel multibits watermarking algorithm providing robustness against geometric attacks. The robustness is achieved from three aspects：（1） Choosing the inscribed disk of the host image as the Zernike moments computation domain and the square in the disk as the watermarking embedding domain. （2） Embedding the watermark in the cascade discrete wavelet transform-discrete cosine transform （DWT-DCT） domain by modulating the specified coefficient pair in each sub block. （3） Saving two selected Zernike moments of the original watermarked image to estimate and correct the geometric attacks before watermark extraction. Experimental results show that the proposed algorithm is robust to any angle of rotation attacks and wide range of scaling attacks, and as well, a variety of other attacks such as lossy compression, common signal processing.

关键词： Zernike moments discrete wavelet transform discrete cosine transform (DWT-DCT) watermarking

Nested RT-PCR method for the detection of European avian-like H1 swine influenza A virus

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Journal of Integrative Agriculture 2016年第5期15卷 1095-1102页

作者： WEI Yan-di PEI Xing-yao ZHANG yuan yu chen-fang SUN Hong-lei LIU Jin-hua PU Juan Key Laboratory of Animal Epidemiology and Zoonosis Ministry of Agriculture/State Key Laboratory of Agrobiotechnology/College of Veterinary Medicine China Agricultural University Beijing 100193 P.R. China China Institute of Veterinary Drug Control Beijing 100086 P.R. China

Swine influenza A virus（swine IAV） circulates worldwide in pigs and poses a serious public health threat, as evidenced by the 2009 H1N1 influenza pandemic. Among multiple subtypes/lineages of swine influenza A viruses, European avian-like（EA） H1N1 swine IAV has been dominant since 2005 in China and caused infections in humans in 2010. Highly sensitive and specific methods of detection are required to differentiate EA H1N1 swine IAVs from viruses belonging to other lineages and subtypes. In this study, a nested reverse transcription（RT）-PCR assay was developed to detect EA H1 swine IAVs. Two primer sets（outer and inner） were designed specifically to target the viral hemagglutinin genes. Specific PCR products were obtained from all tested EA H1N1 swine IAV isolates, but not from other lineages of H1 swine IAVs, other subtypes of swine IAVs, or other infectious swine viruses. The sensitivity of the nested RT-PCR was improved to 1 plaque forming unit（PFU） m L^（-1） which was over 10~4 PFU m L^（-1） for a previously established multiplex RT-PCR method. The nested RT-PCR results obtained from screening 365 clinical samples were consistent with those obtained using conventional virus isolation methods combined with sequencing. Thus, the nested RT-PCR assay reported herein is more sensitive and suitable for the diagnosis of clinical infections and surveillance of EA H1 swine IAVs in pigs and humans.

关键词： nested RT-PCR swine influenza A virus European avian-like H1 HA gene molecular diagnosis

A duplex RT-PCR assay for detection of H9 subtype avian influenza viruses and infectious bronchitis viruses

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Journal of Integrative Agriculture 2016年第9期15卷 2105-2113页

作者： WEI Yan-di GAO Wei-hua SUN Hong-lei yu chen-fang PEI Xing-yao SUN Yi-peng LIU Jin-hua PU Juan Key Laboratory of Animal Epidemiology and Zoonosis Ministry of Agriculture/College of Veterinary Medicine/State Key Laboratory of Agrobiotechnology China Agricultural University

H9 s ubtype avian influenza virus（AIV） and infectious bronchitis virus（IBV） are major pathogens circulating in poultry and have resulted in great economic losses due to respiratory disease and reduced egg production. As similar symptoms are elicited by the two pathogens, it is difficult for their differential diagnosis. So far, no reverse transcription-polymerase chain reaction（RT-PCR） assay has been found to differentiate between H9 AIV and IBV in one reaction. Therefore, developing a sensitive and specific method is of importance to simultaneously detect and differentiate H9 AIV and IBV. In this study, a duplex RT-PCR（d RT-PCR） was established. Two primer sets target the hemagglutinin（HA） gene of H9 AIV and the nucleocapsid（N） gene of IBV, respectively. Spec ific PCR products were obtained from all tested H9 AIVs and IBVs belonging to the major clades circulating in China, but not from AIVs of other subtypes or other infectious avian viruses. The sensitivity of the d RT-PCR assay corresponding to H9 AIV, IBV and mixture of H9 AIV and IBV were at a concentration of 1×10^1, 1.5×10^1 and 1.5×10^1 50% egg infective doses（EID_（50）） m L^–1, respectively. The concordance rates between the d RT-PCR and virus isolation were 99.1 and 98.2%, respectively, for detection of samples from H9N2 AIV or IBV infected chickens, while the concordance rate was 99.1% for detection of samples from H9N2 AIV and IBV co-infected chickens. Thus, the d RT-PCR assay reported herein is specific and sensitive, and suitable for the differential diagnosis of clinical infections and survei llance of H9 AIVs and IBVs.

关键词： avian influenza viruses H9 subtype infectious bronchitis viruses duplex RT-PCR

The Existence of Solutions of Initial Value Problems for Nonlinear Second Order Impulsive Integro-Differential Equations of Mixed Type in Banach Spaces

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Journal of Mathematical Research and Exposition 2008年第3期28卷 501-510页

作者： yu Wei Qin chen fang Qi Department of Mathematics Nanjing University of Aeronautics and Astronautics Jiangsu 210016 China

By the use of MSnch fixed point theorem and a new comparison result, the solutions of initial value problems for nonlinear second order impulsive integro-differential equations of mixed type in Banach spaces are inves... 详细信息

关键词： Banach spaces impulsive integro-differential equations initial value problems measure of noncompactness cone.

重新解读清中前期欧洲来华使团与外交礼仪之争

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史学集刊 2022年第6期 62-70页

作者：陈玉芳吉林大学文学院中国史系吉林长春130012

清中前期,葡萄牙、荷兰、沙俄和英国使团陆续来华。其间,葡、俄、英使臣均与清朝发生过礼仪争执和冲突,主要体现在国书格式和内容与清朝典制不符,使臣觐见皇帝时拒行跪拜礼,使臣坚持亲自呈递国书和方物,以及拒绝被称为“贡使”等方面。... 详细信息

清中前期,葡萄牙、荷兰、沙俄和英国使团陆续来华。其间,葡、俄、英使臣均与清朝发生过礼仪争执和冲突,主要体现在国书格式和内容与清朝典制不符,使臣觐见皇帝时拒行跪拜礼,使臣坚持亲自呈递国书和方物,以及拒绝被称为“贡使”等方面。清朝在面对欧洲来华使团对既有外交礼仪的挑战时,有不同程度的妥协和变通,有时面对不同国家使臣挑起的同一礼仪问题,反应也不同。虽然历次礼仪之争的内容和激烈程度不同,但综合来看,礼仪问题却并非清朝答应或拒绝使团要求的主要原因。清朝拒绝葡、荷、英使臣的要求,却与俄国使臣开展各项谈判并对其诉求做出积极回应,从表面看,这是区别对待西欧各国与俄国使臣的要求,但根本上均是出于消除对统治威胁的考量。

关键词：外交礼仪之争马戛尔尼欧洲中国观欧洲使团

Location of the Protein of RSG6,a Predominantly Expressed Gene in Rice Sperm Cells

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Wuhan University Journal of Natural Sciences 2004年第3期9卷 375-380页

作者： LanLi-qiong Miaochen Zengyu WangSheng-hua Xuying TangLin BAIyu chenfang CollegeofLifeSciences SichuanUniversityChengdu610064SichuanChina

Using Western blot and immunohistochemistry analysis, here the localization ofRSG6 protein was determined in various tissues of rice. Western blot showed only a weak signal in mature pollen. Nevertheless, according to the result of immunohistochemistry with DAB and fluorescent staining, the expression ofRSG6 protein appeared to begin at the bicellular microspore stage, and then keep activity in the sperm cells of mature pollens. The fluorescence pattern showedRSG6 polypeptide was present close to or attached to the surface of the isolated sperm cells. And this suggested thatRSG6 might take an important part in the process of recognition of sperm cell and ovum. Key words Western blot - immunohistochemistry - location - protein - RSG6 - rice CLC number Q 939.91 Foundation item: Supported by the National Natural Science Foundation of China (30270090); the Doctoral Foundation of the Ministry of Education (98061001) and the Key Project of Natural Science Foundation of Sichuan Province.Biography: Lan Li-qiong (1967-) female, Ph. D; research direction: plant developmental biology and reproductive engineering.

关键词： Western blot immunohistochemistry location protein RSG6 rice

Sequencing of p53 mutation in established human hepatocellular carcinoma cell line of HHC4 and HHC15 in nude mice

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World Journal of Gastroenterology 1998年第6期4卷 51-55页

作者： YANG Shan Min, ZHOU Hong, chen Rui Chuan, WANG yu fang, chen Fu, ZHANG Chang Gong, ZHEN yun, YAN Jiang Hua and SU Jin Hua

AIM To set up cell lines of human hepatocellular carcinoma in nude mice for the research of cell biology and gene therapy. METHODS Xenotransplantation of human hepatoma into nude mice was carried out and the growth rate, histopathology and immunology of the nude mice were studied. The DNA from xenografts were analyzed by HBV gene and PCR amplification of a fragment of p 53 gene exon 7, which were identified by dot blot hybridization, restriction fragments length polymorphism and DNA sequencing. RESULTS hHCC4 and hHCC415 cell lines could be successively transplanted in nude mice and the population doubling time was 7 and 5 days respectively. These strains retained the original characteristics of histopathology, secreting AFP and heteroploid karyotypes in human hepatocellular carcinoma. The fragment of HBV gene was detected in the genomic DNA of both hHCC4 and hHCC15, however only hHCC4 secreted HBsAg. The mutation at 250 code (C→A) and 249 code (G→T) were detected respectively in the genomic DNA of hHCC4 and hHCC15. CONCLUSION The two cell lines are useful material for studying cell biology and gene therapy in human hepatocellular carcinoma and provide molecular biological trace of the relationship between high mortality of hepatoma and AFB1 severe pollution of the daily common foods in this district.

关键词： Liver neoplasms carcinoma, hepatocellular p53 gene mutation HHC4 HHC15 Tumor cell, cultured

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富锂层状氧化物正极材料研究进展

无机材料学报 2017年第8期32卷 792-800页

作者：陈宇方李宇杰郑春满谢凯陈重学国防科学技术大学指挥军官基础教育学院长沙410073 国防科学技术大学航天科学与工程学院长沙410073 武汉大学动力与机械学院武汉430072

富锂层状氧化物正极材料(xLi_2MnO_3·(1–x)LiMO_2(M=Ni_yMn_zCo_(1-y-z)….)理论容量高、价格低廉,是新一代锂离子电池正极材料的候选之一。本文概述了该正极材料的结构,分析了其在电化学活化过程与循环过程中结构的演变,探讨了结构... 详细信息

富锂层状氧化物正极材料(xLi_2MnO_3·(1–x)LiMO_2(M=Ni_yMn_zCo_(1-y-z)….)理论容量高、价格低廉,是新一代锂离子电池正极材料的候选之一。本文概述了该正极材料的结构,分析了其在电化学活化过程与循环过程中结构的演变,探讨了结构变化对正极材料电化学性能的影响规律,并概括了目前针对该类正极材料电化学性能提升所开展的离子掺杂和表面改性的研究工作,展望了未来富锂层状氧化物正极材料的发展方向。

关键词：富锂层状氧化物活化和循环过程晶相结构演变表面改性离子掺杂综述