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Evolutionary implications of Avian Infectious Bronchitis Virus(AIBV)analysis

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Cell Research 2006年第3期16卷 323-327页

作者： Peng Shi~(1,2. Li Yu~2.Yun-xin Fu~3 Jing-Fei Huang~1 Ke-Qin Zhang~2.Ya-ping Zhang~(1,2.1 Laboratory of Cellular and Molecular Evolution,and Molecular Biology of Domestic Animals,Kunming lnstitute of Zoology,Chinese Academy of Sciences,Kunming 6502.3,china 2.Laboratory for Conservation and Utilization of Bio-resource,Yunnan University,Kunming 650091,china 3 Human Genetics Center,University of Texas at Houston,Houston,Texas 77030,USA Laboratory of Cellular and Molecular Evolution and Molecular Biology of Domestic Animals Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China.

For developing efficient vaccines,it is essential to identify which amino acid changes are most important to the sur-vival of the *** investigate the amino acid substitution features in the Avian Infectious Bronchitis Virus (AIBV)antigenic domain of a vaccine serotype (DE072. and a virulent viral strain (GA98) to better understand adaptive evo-lution of *** addition,the SARS Coronavirus (SARS-CoV) was also analyzed in the same *** is interestingto find that extreme comparability exists between AIBV and SARS in amino acid substitution *** suggests thatamino acid changes that result in overall shift of residue charge and polarity should be paid special attention to duringthe development of vaccines.

关键词： Avian Infectious Bronchitis Virus SARS Coronavirus positive selection adaptive evolution vaccine development

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4,5 1 Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education, institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875, china 2.Beijing Radiation Center, Beijing 100875, china 3 Laboratory of Optical Physics, institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 4 Key Laboratory of Advanced Materials of the Ministry of Education, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, china 5 Beijing National Center for Electron Microscopy, Tsinghua University, Beijing 100084, china Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China Beijing Radiation Center Beijing China Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing China Key Laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing China Beijing National Center for Electron Microscopy Tsinghua University Beijing China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3+ ions are partly converted into Mn2. and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

WHEN THE KUNLUN *** AREA UPLIFTED TO PRESENT ELEVATION

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地学前缘 2000年第S1期7卷 201-202页

作者： Wu Yongqiu 1,2., Cui Zhijiu 3, Ge Daokai 3, Liu Gengnian 3[WT5,5”BX](1 institute of resources Science, Beijing Normal University, Beijing 100875, {2. Fax:+86(10)62.08178 E\|mail: yqwu@*** 2.Key Laboratory of Environmental Change and

Introduction There are big disputes on the uplift of the Tibetan Plateau. Some scientists believe the plateau uplifted to its highest elevation by 14Ma BP,and it decreased in elevation afterward. The second idea about the uplift of the plateau was similar to the first one in tectonic theory, but they consider the time of C3 plant change to C4 in the South Asia, as the time when the plateau reached its highest elevation. This time is 8Ma BP. The third idea, the most Chinese scientists believed, the nearest uplift of the plateau took place since 3 4Ma BP. The occurrence of fault depression and gravel deposit with large thickness in the inner and the marge of the plateau represented the speed uplift. After the collision of the India plate and the Eurasia plateau by the 36Ma, the Tibetean area uplifted several times, but it had been planed to lower area. The plateau with 4500m elevation formed in the Quaternary. While our recent research in the Kunlun Pass area suggest , the nearest uplift occurred at the border of the Early and Middle Pleistocene, and before that time, the elevation of this area was no more than 1500 m.

关键词： Kunlun Mts. Pass area uplift present elevation

CeO_2.加剂对等离子ZrO_2.层抗热震性的影响

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中国稀土学报 2003年第2期21卷 247-249页

作者：李慕勤马臣邵德春郭面焕佳木斯大学材料学院黑龙江省生物医学材料重点实验室黑龙江佳木斯154007 哈尔滨工业大学黑龙江哈尔滨150001

在ZrO2.瓷涂层中加入适量的CeO2.使陶瓷涂层的抗热震性能得到提高,这主要是由于CeO2.加入,涂层的微小孔隙增加、涂层产生细微的网状裂纹,增加了微裂纹密度,从而降低了涂层的弹性模量,释放了涂层中的应力,提高了涂层的裂纹失稳扩展时... 详细信息

在ZrO2.瓷涂层中加入适量的CeO2.使陶瓷涂层的抗热震性能得到提高,这主要是由于CeO2.加入,涂层的微小孔隙增加、涂层产生细微的网状裂纹,增加了微裂纹密度,从而降低了涂层的弹性模量,释放了涂层中的应力,提高了涂层的裂纹失稳扩展时的临界温差ΔTc,并可阻止裂纹沿单方向的快速扩展,使涂层的抗热震起裂性能和抗热震失效能力得到提高。其中,CeO2.入量为9%效果最佳,过量加入CeO2.会过早地促进裂纹的扩展、断裂,不利于提高涂层的抗热震性能。

关键词：无机非金属材料 CeO2 陶瓷涂层抗热震性稀土

Preparation of Glycyrrhetinic Acid Monoglucuronide by Selective Hydrolysis of Glycyrrhizic Acid via Biotransformation

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Chinese Herbal Medicines 2012年第4期4卷 324-328页

作者： LU Li1,2.ZHAO Yang1,YU He-shui1,2.HUANG Hong-zhi1,2.KANG Li-ping1,2.CAO Man1,2.CUI Jiang-ming1,YU Li-yan3,SONG Xin-bo2.MA Bai-ping1 1.Beijing institute of Radiation Medicine,Beijing 100850,china 2.Tianjin University of Traditional Chinese Medicine,Tianjin 300193,china 3.institute of Medicinal Biotechnology,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100050,china Beijing institute of Radiation Medicine Beijing 100850 China Tianjin University of Traditional Chinese Medicine Tianjin 300193 China institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

Objective To search for the microorganisms which have the high selectivity of hydrolyzing glycyrrhizic acid(GL) into 18β-glycyrrhetinic acid-3-O-β-D-glucuronide(GAMG) without glycyrrhetinic acid(GA) *** GL was biotransformed by Aspergillus sp.,the products were separated by chromatography on reverse phase C18 column and semi-preparative HPLC,and their structures were elucidated on the basis of HR-ESI-MS,1D NMR(1H-NMR,13C-NMR,and NOESY) and 2. NMR(1H-1H COSY,HSQC,and HMBC) spectral *** Aspergillus *** partially hydrolyze GL into GAMG(3),along with two minor byproducts,3-O-β-D-glucuronopyranosyl-18β-liquiritic acid(1) and 3-O-β-D-glucuronopyranosyl-2.-hydroxy-18β-glycyrrhetinic acid(2..Conclusion Aspergillus *** the high selectivity of hydrolyzing GL into GAMG without GA byproduct and the yield of GAMG is about 60%.The complete assignments of 1H-NMR and 13C-NMR data for compounds 1 and 2.are reported for the first time.

关键词： Aspergillus sp. biotransformation 18β-glycyrrhetinic acid 3-O-β-D-glucuronide glycyrrhizic acid NMR

THE HARM OF CROFTON WEED AND EXOTIC PEST INVASION

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THE HARM OF CROFTON WEED AND EXOTIC PEST INVASION

Conjugate adjoining problem in braid groups and new design of braid-based signatures

The ⅩⅤth International Plant Protection Congress

作者： JIANG Hui1 ZHOU Su2.and CHEN Su-qing1 1Sichuan Phytosanitary Station No.4 Wuhouci Street chengdu 610041 china 2.ichuan Provincial General Station for Grassland Management chengdu 610041 china

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Science china(Information Sciences) 2010年第3期53卷 524-536页

作者： WANG LiCheng1,2. WANG LiHua2. CAO ZhenFu3, YANG YiXian1 & NIU XinXin1 Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 100876, china 2.ational institute of Information and Communications Technology, Tokyo 184-8795, Japan 3Trusted Digital Technology Laboratory, Shanghai Jiao Tong University, Shanghai 2.02.0, china Information Security Center State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China National institute of Information and Communications Technology Tokyo Japan Trusted Digital Technology Laboratory Shanghai Jiao Tong University Shanghai China

The development of quantum computation casts serious threats to the securities of most existing public-key cryptosystems. Braid-based cryptography is one of the alternatives that have potential advantages in resisting quantum attacks. In this paper, the state of the art of braid cryptography is surveyed, and then a new cryptographic problem-conjugate adjoining problem related to braid groups is proposed. Based on this problem, we design a new braid-based signature scheme. This scheme is efficient and provably secure in the random oracle model. Further, we present the comparison between braid-based signatures and RSA-based ones. The signing process of the braid-based schemes is more efficient than that of RSA-based ones, while the verifying process of the braid-based ones is observably slow. Hence, braid-based signatures are suitable for scenarios where the signing process has to be as quick as possible but delays are permitted in the verifying process, for example, in off-line e-cash systems. The key sizes in braid-based schemes are considerably large-about 2. bits in the case of secret keys and 12. bits in the case of public keys. However, braid operations are much simpler and more efficient than modular exponential operations. Therefore, braid-based schemes can be embedded into devices with low computational ability and large memory space. The capability of braid cryptosystems to resist currently known quantum attacks is also discussed from the perspective of hidden subgroup problems.

关键词： braid group conjugate adjoining problem digital signature provable security resistance to quantum attack

STUDY ON WETLAND LOSS AND ITS REASONS IN china

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Chinese Geographical Science 2001年第3期11卷 50-54页

作者： HE Yan 1 ,ZHANG Ming-xiang 2.3 (1.The Chinese Academy of Sciences,B eijing 100864,P.R.china 2.Changchun institute of Geography,the Chinese Academy of Sciences,Changchun 13002.,P.R.china 3.Wetland resources Monitoring Center,State Forestry Admi

Wetlands are ecosystems with many f *** the general public and government lack a comprehen-sive understanding of the importance of wetland benefits,thus making bl indly exploitation,wetland resour ces decreasing and losing *** wetlands in china,as in most countries,have suffered heavily from the pressure o f develop-ment and have confronted with the thr eats of *** paper takes Sanjian g Plain marshes,lakes in the middle r eaches of the Changjiang(Yangtze)River,coastal wetlands and mangroves as cases to study wetland loss in china,and puts forward main existing reasons of wetland loss,such as blindly reclamati on and exploitation of wetland resou rces,over-exploitation of bio-resource s in wetland,*** recently,there has been a growing recognition of t he benefits of wetlands and a wide range of legal and regulatory initiatives have been undertaken which are designed to impro ve wetland management and *** the basis of the above analysis,the paper brings forward some suggestions on wetland conservation.

关键词： wetland resource wetland loss loss reason china’s wetland

Combination and superimposition of source kitchens and their effects on hydrocarbon accumulation in the hinterland of the Junggar Basin,west china

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Petroleum Science 2010年第1期7卷 59-72页

作者： Zhang Zhihuan Qin Liming Qiu Nansheng Zhong Ningning Zhang Zhenying Li Wei State Key Laboratory of Petroleum resources and Prospecting China University of Petroleum Beijing 102249 China Beijing institute of Economic Management Hebei 102602 China SINOPEC International Petroleum Exploration and Production Corporation Beijing 100083 China

In the hinterland of the Junggar Basin, there are multiple depressions with multiple sets of source rocks. Therefore, the conditions of hydrocarbon sources are complex, and the geochemical characteristics and sources of hydrocarbon vary in different structural belts. The evolution of the Che- Mo palaeohigh affected the formation of hydrocarbon source kitchens and hydrocarbon migration. We studied the combination and superimposition of hydrocarbon source kitchens, using as an example the hinterland of the Junggar Basin （including the Yongjin, Zhengshacun, Moxizhuang and Luliang uplift areas）. The study was based on geochemical analyses of crude oil and fluid inclusions, and the histories of tectonic evolution and hydrocarbon generation. The results indicated that before the Paleogene there were two hydrocarbon-generating depressions： the Western Well Penl depression and the Changji depression on the south and north sides of the Che-Mo palaeohigh, respectively. The Permian source kitchen had been generating hydrocarbon continuously since Triassic and reached high maturity stage in the Cretaceous period. After Paleogene, the adjustment of the Che-Mo palaeohigh led to the subsidence of the Changji depression and the Jurassic source rocks reached mature stage and became the main source kitchens. However, the Jurassic source rocks in the Western Well Penl depression were still in a low maturity stage and did not generate oil because of the adjustment of tectonic movements. As a result, in the central and southern parts of the Junggar Basin, Jurassic source rocks generated oil, but in the Luliang uplift, the crude oil was from the Permian source rocks in the Western Well Penl depression and the Jurassic source rocks did not contribute. The crude oil in the central Zhengshacun-Moxizhuang belt was from the Permian source rocks in two depressions, and partially from the Jurassic source rocks. The crude oil in the Luliang uplift was from the source rocks of the lower Permian F

关键词： Hinterland of the Junggar Basin hydrocarbon source kitchen oil source combination and superimposition accumulation stage