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| 1 | Survey of the research on dynamic weapon-target assignment problem显示文摘The basic concepts and models of weapon-target assignment (WTA) are introduced and the mathematical nature of the WTA models is also analyzed. A systematic survey of research on WTA problem is provided. The present research on WTA is focused on models and algorithms. In the research on models of WTA, the static WTA models are mainly studied and the dynamic WTA models are not fully studied in deed. In the research on algorithms of WTA, the intelligent algorithms are often used to solve the WTA problem. The small scale of static WTA problems has been solved very well, however, the large scale of dynamic WTA problems has not been solved effectively so far. Finally, the characteristics of dynamic WTA are analyzed and directions for the future research on dynamic WTA are discussed. | Cai Huaiping Liu Jingxu Chen Yingwu Wang Hao | 2006 | Journal of Systems Engineering and Electronics2006,17,3: | 43 |
| 2 | NUMERICAL SIMULATION OF FLOW THROUGH ORIFICE ENERGY-DISSIPATORS IN XIAOLANGDI FLOOD-DISCHAR-GE TUNNEL显示文摘The cavitation of orifi ces is one of the main problems of the Xiaolangdi flood discharge tunnels. Along with the decompression experiment, the flow field was calculated in this paper by using an axis-symmetrical k-ε turbulence model. The calculated pressur e distribution was compared with the measured data and in agreement with each ot her. The calculated results show that few of the cavitation bubbles generating a t the orifice edge can reach the wall under the calculation condition, the force applied on the orifice surface and the flow pattern before the orifice may be i mproved obviously by adding the vortex elimination ring at the upper side of the orifice. | Qu, Jingxue Xu, Weilin Yang, Yongquan Wang, Wei Diao, Mingjun | 2000 | Journal of Hydrodynamics2000,12,3: | 14 |
| 3 | Ice radar investigation at Dome A, East Antarctica:Ice thickness and subglacial topography显示文摘Dome A, located in the central East Antarctic ice sheet (EAIS), is the highest summit of the Antarctic ice sheet. From ice-sheet evolution modeling results, Dome A is likely to preserve over one million years of the Earth's paleo-climatic and -environmental records, and considered an ideal deep ice core drilling site. Ice thickness and subglacial topography are critical factors for ice-sheet models to determine the timescale and location of a deep ice core. During the 21st and 24th Chinese National Antarctic Research Expedition (CHINARE 21, 2004/05; CHINARE 24, 2007/08), ground-based ice radar systems were used to a three-dimensional investigation in the central 30 km×30 km region at Dome A. The successfully obtained high resolution and accuracy data of ice thickness and subglacial topography were then interpolated into the ice thickness distribution and subglacial topography digital elevation model (DEM) with a regular grid resolution of 140.5 m×140.5 m. The results of the ice radar investigation indicate that the average ice thickness in the Dome A central 30 km×30 km region is 2233 m, with a minimal ice thickness of 1618 m and a maximal ice thickness of 3139 m at Kunlun Station. The subglacial topography is relatively sharp, with an elevation range of 949-2445 m. The typical, clear mountain glaciation morphology is likely to reflect the early evolution of the Antarctic ice sheet. Based on the ice thickness distribution and subglacial topography characteristics, the location of Kunlun Station was suggested to carry out the first high-resolution, long time-scale deep ice core drilling. However, the internal structure and basal environments at Kunlun Station still need further research to determine. | CUI XiangBin SUN Bo TIAN Gang TANG XueYuan ZHANG XiangPei JIANG YunYun GUO JingXue LI Xin | 2010 | Chinese Science Bulletin2010,55,4: | 11 |
| 4 | Preliminary results of ice radar investigation along the traverse between Zhongshan and Dome A in East Antarctic ice sheet:Ice thickness and subglacial topography显示文摘During the 24th Chinese National Antarctic Research Expedition(CHINARE 24,2007/08),a ground-based ice radar was used to survey ice thickness and subglacial topography along the 1170 km traverse between Zhongshan and Dome A in East Antarctic ice sheet(EAIS).Ice-bedrock interface was detected along 82%of the traverse and data was collected at a horizontal resolution of <5.6 m.The data was processed to produce curves of ice thickness distribution and subglacial topography along the traverse.The results indicate that,along the traverse,the average ice thickness is 2037 m,smaller than the average ice thickness in EAIS;the thickest ice is at 730 km,and the thinnest ice(891 m)is at the edge of the ice sheet,but the slightly larger ice thickness(1078 m) in inland appears at 1020 km;the average subglacial topography elevation is 728 m,greatly larger than the average value in EAIS, and the largest elevation reaches up to 2650 m at 1034 km.The lowest terrain is located at 765 km.In further inland of 900?1170 km,the subglacial topography is relatively high due to the existence of the Gamburtsev Subglacial Mountains in the region.Generally,the influence of subglacial topography on ice surface is not significant,except at 900 km where great rise of subglacial topography causes evident uplift of ice surface.Where ice-bedrock interface was detected,the frequent and strong change of ice thickness and subglacial topography in small-scale means large bedrock roughness along the traverse,and is considered as the result of the integrated influence of ice flow,basal environments and geology.The segment where bedrock was not detected has very large ice thickness.The strong ice flow there also makes internal structure more complicated and induces serious attenuation of radar signals. | CUI XiangBin SUN Bo TIAN Gang TANG XueYuan ZHANG XiangPei JIANG YunYun GUO JingXue LI Xin | 2010 | Chinese Science Bulletin2010,55,24: | 8 |
| 5 | Pathogenicty and immune prophylaxis of cag pathogenicity island gene knockout homogenic mutants显示文摘AIM: To clarify the role of cag pathogenicity island (cagPAI) of Helicobacter pylori (H pylori) in the pathogenicity and immune prophylaxis of H pylori infection. METHODS: Three pairs of H pylori including 3 strains of cagPAI positive wildtype bacteria and their cagPAI knockout homogenic mutants were utilized. H pylori binding to the gastric epithelial cells was analyzed by flow cytometry assays. Apoptosis of gastric epithelial cells induced by H pylori was determined by ELISA assay. Prophylaxis effect of the wildtype and mutant strains was compared by immunization with the sonicate of the bacteria into mice model. RESULTS: No difference was found in the apoptasis between cagPAI positive and knockout H pylori strains in respective of the ability in the binding to gastric epithelial cells as well as the induction of apoptosis. Both types of the bacteria were able to protect the mice from the infection of H pylori after immunization, with no difference between them regarding to the protection rate as well as the stimulation of the proliferation of splenocytes of the mice. CONCLUSION: The role of cagPAI in the pathogenicity and prophylaxis of Hpyloriinfection remains to be cleared. | Huan-JianLin JingXue YangBai Ji-DeWang Ya-LiZhang Dian-YuanZhou | 2004 | World Journal of Gastroenterology2004,10,22: | 7 |
| 6 | A Genome Sequence of Novel SARS-CoV Isolates: the Genotype, GD-Ins29, Leads to a Hypothesis of Viral Transmission in South China显示文摘We report a complete genomic sequence of rare isolates (minor genotype) of theSARS-CoV from SARS patients in Guangdong, China, where the first few casesemerged. The most striking discovery from the isolate is an extra 29-nucleotidesequence located at the nucleotide positions between 27,863 and 27,864 (referredto the complete sequence of B J01) within an overlapped region composed of BGI-PUP5 (BGI-postulated uncharacterized protein 5) and BGI-PUP6 upstream ofthe N (nucleocapsid) protein. The discovery of this minor genotype, GD-Ins29,suggests a significant genetic event and differentiates it from the previously re-ported genotype, the dominant form among all sequenced SARS-CoV isolates. A17-nt segment of this extra sequence is identical to a segment of the same size intwo human mRNA sequences that may interfere with viral genome replication andtranscription in the cytosol of the infected cells. It provides a new avenue for theexploration of the virus-host interaction in viral evolution, host pathogenesis, andvaccine development. | E‘deQin XiongleiHe WeiTian YongLiu WeiLi JieWen BingyinSi YongwuHu WenmingPeng LinTaug TaoJiang JianpingShi JiaJia YuZhang JiaYe Cui’eWang YujunHan JingqiangWang BaochangFan QingfaWu GuohuiChang WuchunCao ZuyuanXu RuifuYang JmgWang ManYu YanLi JingXu JunZhou YajumDeng XiaoyuLi JianfeiHu CaipingWang ChunxiaYan QingrunZhang JingyueBao GuoqingLi HaiqingZhang YilinZhang HuiZhao XiaoweiZhang ShuangliLi XiaoJieCheng XiuqingZhang BinLiu ChangqingZeng HuanmingYang WeijunChen LinFang ChangfengLi MengLei DaweiLi WeiTong XiangjunTian JianWang BoZhang SonggangLi XuehaiTan SiqiLiu WeiDong JunWang GaneKa-ShuWong JunYu QingyuZhu | 2003 | Genomics, Proteomics & Bioinformatics2003,1,2: | 6 |
| 7 | Anti-liver cancer activity of TNF-related apoptosis-inducing ligand gene and its bystander effects显示文摘AIM:To observe the anti-liver cancer activity of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene and its bystander effects on hepatocellular carcinoma (HCC) cell line SMMC7721.METHODS:Full-length cDNA of human TRAIL was transferred into SMMC7721 cells with a binary adenoviral vector system.Polymerase-chain reaction following reverse transcription (RT-PCR) was used to determine the expression of TRAIL gene. Effects of the transfected gene on proliferation of SMMC7721 cells were measured by MTT assay. Its influence on apoptosis was demonstrated by fluorescence-activated cell sorting (FACS). The bystander effect was observed by co-culturing the SMMC7721 cells with and without the transfected TRAIL gene at different ratios, and the culture medium supernatant from the transfected cells was also examined for its influence on SMMC7721 cells.RESULTS:The growth-inhibition rate and apoptotic cell fraction in the cells transfected with the TRAIL gene, Bax gene or only LacZ gene were 91.2%, 48.0%, 28.8% and 29.1%, 12.5%, 6.6%, respectively. The growth-inhibition rate of transfection with these three sequences in normal human fibroblasts was 6.1%, 45.5% and 7.6%, respectively,indicating a discriminative inhibition of TRAIL transfection on the cancer cells. In the co-culturing test, addition of the transfected TRAIL to SMMC7721 cells in proportions of 5%,25%, 50%, 75% and 100%, resulted in a growth-inhibition of 15.9%, 67%, 80.2%, 86.4% and 87.7%, respectively.We failed to observe a significant growth-inhibition effect of the culture medium supernatant on SMMC7721 cells.CONCLUSION: TRAIL gene transferred by a binary adenoviral vector system can inhibit proliferation of SMMC7721 cellsand induce their apoptosis. A bystander effect was observed,which seemed not to be mediated by soluble factors. | ChaoHe Wei-FengLao Xiao-TongHu Xiang-MingXu JingXu Bing-LiangFang | 2004 | World Journal of Gastroenterology2004,10,5: | 6 |
| 8 | Chinese radioglaciological studies on the Antarctic ice sheet: progress and prospects显示文摘Chinese radioglaciological studies on the Antarctic ice sheet(AIS) began in 2004/05 when the 21 st Chinese National Antarctic Research Expedition(CHINARE 21) team arrived at Dome A for the first time and radio echo sounding(RES) was conducted along the inland traverse and in the Dome A region. Subsequently, more field surveys were conducted along the traverse and in the Dome A region using different radar systems targeting different scientific purposes, such as revealing the landscape of the Gamburtsev Subglacial Mountains by detailed grid RES, or locating a deep ice core drilling site by mapping and studying internal structures, bedrock topography and subglacial conditions in the Dome A region. Furthermore, the evolution of the AIS was inferred from the typical mountain glaciation topography beneath Dome A, and the age of the deep ice core at Kunlun Station was estimated through numerical modeling. Recently, the Snow Eagle 601 airplane was acquired and an airborne geophysical system was constructed to survey the AIS in Princess Elizabeth Land during CHINARE 32(2015/16) and CHINARE 33(2016/17) in order to fill the large data gap there. In this paper, we review both the recent progress of Chinese radioglaciological science in Antarctica and future proposed work. | CUI Xiangbin WANG Tiantian SUN Bo TANG Xueyuan GUO Jingxue | 2017 | Advances in Polar Science2017,28,3: | 6 |
| 9 | Microenvironment Modulation in Metal−Organic Framework-Based Catalysis显示文摘CONSPECTUS:The fine design and regulation of catalysts play critical roles in the development of catalysis.The microenvironment,which gives rise to unique spatial structures and electronic properties around catalytic sites,has been proven to dramatically regulate catalytic behavior in enzymes and homogeneous catalysis.However,understanding the microenvironment modulation(MEM)of catalytic sites remains challenging and very limited in heterogeneous catalysis mainly due to the lack of structural precision and/or tailorability of traditional solid catalysts.Among diverse materials,metal−organic frameworks(MOFs),a class of porous crystalline solids,have been intensively studied as heterogeneous catalysts in recent years.The atomically precise and well tunable structures of MOFs make them an ideal platform for rationally regulating the microenvironment surrounding catalytic sites.Accordingly,their well-defined structures hold great promise for elucidating how the microenvironment modulation affects the resulting catalytic performance.Nevertheless,the investigations of accurate control over the microenvironment of catalytic sites in MOFs for modulated catalysis are still very limited.Therefore,it is of great importance to summarize the related results and provide in-depth insights into microenvironment modulation in MOF-based catalysis,accelerating the future development of this emerging research topic.In this Account,we have presented a summary of our recent attempts to optimize the catalytic performance of MOF-based materials via microenvironment modulation.In view of the unique component and structural advantages of MOFs,we deliver the general fundamentals for rational control over the microenvironment in MOF-based catalysis.Initially,the great opportunities brought about by MOFs for accurate control over microenvironment engineering,including the origin of abundant active sites,flexible regulation strategies,and well-defined structure,are introduced in detail.In the next section,we focus on the specific strategies of microenvironment modulation in MOF-based catalysis,which dominate the molecular/electron-transfer process and regulate the intrinsic activity of catalytic sites.Meanwhile,the related chemical basis and underlying structure−property relationship behind the enhanced catalytic performance will be highlighted.Finally,the major challenges and future outlooks on the microenvironment modulation in MOF-based catalysis will be further discussed.It is expected that this Account would provide an understanding of the importance of microenvironment modulation around catalytic sites in MOF-based catalysts and afford significant inspiration toward enhanced performance by microenvironment engineering in heterogeneous catalysis. | Long Jiao Jingxue Wang Hai-Long Jiang | 2021 | Accounts of Materials Research2021,2,5: | 5 |
| 10 | A CAHN-HILLIARD TYPE EQUATION WITH GRADIENT DEPENDENT POTENTIAL显示文摘 | Yin Jingxue Huang Rui | 2008 | Journal of Partial Differential Equations2008,21,1: | 4 |
| 11 | A series of aminoamides used for flotation of kaolinite显示文摘N-(2-aminoethyl)-dodecanamide, N-(3-dimethylaminopropyl)-dodecanamide, and N-(3-diethylaminoproyl)-dodecanamide used as collectors were studied for the flotation of kaolinite in the absence of additives at different pulp phs as well as different collector contents. The effectiveness of the long chain aminoamides on pure kaolinite was demonstrated in laboratory scale flotation tests. The adsorption mechanism of the aminoamides onto kaolinite was investigated through zeta potential determinations and infrared spectrometry. The -98 μm size fractions of kaolinite, taken from Jiaxian Henan of China, were used in flotation. The hydrophilic group size of the aminoamides has a relatively less influence upon the floatability of pure kaolinite. The results suggest either the static-electric force or the coordinating bond adsorption mechanism of the aminoamides onto kaolinite depends on pulp pH. | ShiminZhao DianzuoWang YuehuaHu JingXu XiaolingZhao | 2005 | Journal of University of Science and Technology Beijing2005,12,3: | 4 |
| 12 | Cellulose nanofiber separator for suppressing shuttle effect and Li dendrite formation in lithium-sulfur batteries显示文摘Lithium-sulfur battery(LSB) has high energy density but is limited by the polysulfides shuttle and dendrite growth during cycling. Herein, a free-standing cellulose nanofiber(CNF) separator is designed and fabricated in isopropanol/water suspension through vacuum filtration progress. CNFs with abundant polar oxygen-containing functional groups can chemically immobilize the polysulfides, and suppress the formation of the dendrites by controlling the surface morphology of the SEI on lithium metal in LSB. The isopropanol content in a suspension can fine-tune the pore structure of the membrane to achieve optimal electrochemical performance. The prepared separator displays integrated advantages of an ultrathin thickness(19 μm), lightweight(0.87 mg cm^(-2)), extremely high porosity(98.05%), and decent electrolyte affinity. As a result, the discharge capacity of the LSB with CNF separator at the first and 100 th cycle is 1.4 and 1.3 times that of PP separator, respectively. Our research provides an environmentalfriendly and facile strategy for the preparation of multifunctional separators for LSBs. | Jingxue Li Liqin Dai Zhefan Wang Hao Wang Lijing Xie Jingpeng Chen Chong Yan Hong Yuan Hongliang Wang Chengmeng Chen | 2022 | Journal of Energy Chemistry2022,31,4: | 4 |
| 13 | Forest plant and macrofungal differences in the Greater and Lesser Khingan Mountains in Northeast China:A regional-historical comparison and its implications显示文摘Forests in Northeast China in the Greater and Lesser Khingan Mountains(GKM and LKM)account for nearly 1/3 of the total state-owned forests in the country.Regional and historical comparisons of forest plants and macrofungi will favor biological conservation,forest management and economic development.A total of 1067 sampling plots were surveyed on forest composition and structure,with a macrofungi survey at Liangshui and Huzhong Nature Reserves in the center of two regions.Regional and historical differences of these parameters were analyzed with a redundancy ordination of their complex associations.There were 61-76 families,189-196 genera,and 369-384 species,which was only 1/3 of the historical records.The same dominant species were larch and birch with Korean pine(a climax species)less as expected from past surveys in the LKM.Shrub and herb species were different in the two regions,as expected from historical records.There was 10-50%lower species diversity(except for herb evenness),but 1.8-to 4-time higher macrofungi diversity in the GKM.Compared with the LKM,both tree heights and macrofungi density were higher.Nevertheless,current heights averaging 10 m are half of historical records(>20 m in the 1960s).Edible macrofungi were the highest proportion in both regions,about twice that of other fungal groups,hav-ing important roles in the local economy.A major factor explaining plant diversity variations in both regions was herb cover,followed by shrubs in the GKM and herb-dominant species in the LKM.Factors responsible for macrofungi variations were tree density and shrub height.Vaccinium vitis-idaea and Larix gmelinii in the GKM but tree size and diversity were important factors in the LKM.Our findings highlighted large spatial and historical differences between the GKM and LKM in plant-macrofungal composition,forest structure,and their complex associations,which will favor precise conservation and management of forest resources in two region in the future. | Yuanyuan Wang Hui Wen Kai Wang Jingxue Sun Jinghua Yu Qinggui Wang Wenjie Wang | 2022 | Journal of Forestry Research2022,33,2: | 3 |
| 14 | Numerical simulation of counter-current flow field in the downcomer of a liquid-solid circulating fluidized bed显示文摘A comprehensive study on the hydrodynamics in the downcomer of a liquid-solid circulating fluidized bed(LSCFB) is crucial in the control and optimization of the extraction process using an ion exchange LSCFB.A computational fluid dynamics model is proposed in this study to simulate the counter-current two-phase flow in the downcomer of the LSCFB.The model is based on the Eulerian-Eulerian approach incorporating the kinetic theory of granular flow.The predicted results agree well with our earlier experimental data.Furthermore,it is shown that the bed expansion of the particles in the downcomer is directly affected by the superficial liquid velocity in downcomer and solids circulation rate.The model also predicts the residence time of solid particles in the downcomer using a pulse technique.It is demonstrated that the increase in the superficial liquid velocity decreases the solids dispersion in the downcomer of the LSCFB. | Abbas Dadashi Chao Zhang Jingxu(Jesse)Zhu | 2015 | Particuology2015,13,4: | 3 |
| 15 | Continuous Solutions of the First Boundary Value Problems for Nonlinear Diffusion Equations | Yin Jingxue Department of Mathematics Jilin University Changchun,130023 China | 1994 | Acta Mathematica Sinica,English Series1994,10,1: | 3 |
| 16 | Environmental taxation and regional inequality in China显示文摘In order to combat environmental pollution, China enacted the Environmental Protection Tax Law in early 2018. Yet the impacts of the environmental tax on individual regions with different socioeconomic statuses, which are crucial for social justice and public acceptance, remain unclear. Based on a MultiRegional Input-Output(MRIO) table and a nationally regulated tax payment calculation method, this study analyzes the distributional impacts of an environmental tax based upon province’s consumption from both inter-provincial and rural-urban aspects. The national tax revenue based on the current levy mechanism is estimated to be only one seventh of the economic loss from premature mortality caused by ambient particulate matter(PM2.5). The taxation may slightly alleviate urban-rural inequality but may not be helpful with reducing inter-provincial inequality. We further analyze two alternative levy mechanisms. If each province imposes taxes to products it consumes(rather than produces, as in the current mechanism), with the tax rate linearly dependent on its per capita consumption expenditure, this would moderately increase the national tax revenue and significantly reduce inter-provincial inequality.To better compensate for the economic costs of air pollution and reduce regional inequality, it would be beneficial to increase the tax rate nationwide and implement a levy mechanism based on provincially differentiated levels of consumption and economic status. | Jingxu Wang Jintai Lin Kuishuang Feng Peng Liu Mingxi Du Ruijing Ni Lulu Chen Hao Kong Hongjian Weng Mengyao Liu Giovanni Baiocchi Yu Zhao Zhifu Mi Jing Cao Klaus Hubacek | 2019 | Science Bulletin2019,64,22: | 3 |
| 17 | The development road of ammonium phosphate fertilizer in China显示文摘Ammonium phosphate fertilizer is the compounds containing nitrogen and phosphorus that are usually produced through the neutralization reaction of phosphoric acid and ammonia.At present,there are a variety of products,such as slurry monoammonium phosphate(MAP),diammonium phosphate(DAP),industrial grade MAP,water soluble MAP,water soluble ammonium polyphosphate(APP)and so on.After more than 60 years of development,China’s ammonium phosphate fertilizer industry has experienced the road of from scratch and from weak to strong.The successful development of the slurry MAP technology ended the history that the high concentration phosphate fertilizer cannot be produced by using the medium and low grade phosphate ore.The continuous,stable and large-scale production of DAP plant provides sufficient guarantee for DAP products in China.The development of new ammonium phosphate fertilizer products,such as industrial grade MAP,water soluble MAP,water soluble APP,provides technical support for the transformation and upgrading of phosphorus chemical enterprises.In this paper,the production methods,the development history and the latest research progress of ammonium phosphate fertilizers were reviewed. | Dehua Xu Benhe Zhong Xinlong Wang Xue Li Yanjun Zhong Zhengjuan Yan Jingxu Yang Xiaobin Li Yumei Wang Xiaohou Zhou | 2022 | Chinese Journal of Chemical Engineering2022,35,1: | 3 |
| 18 | Predicting the grades of Astragali radix using mass spectrometrybased metabolomics and machine learning显示文摘Astragali radix(AR,the dried root of Astragalus)is a popular herbal remedy in both China and the United States.The commercially available AR is commonly classified into premium graded(PG)and ungraded(UG)ones only according to the appearance.To uncover novel sensitive and specific markers for AR grading,we took the integrated mass spectrometry-based untargeted and targeted metabolomics approaches to characterize chemical features of PG and UG samples in a discovery set(n=16 batches).A series of five differential compounds were screened out by univariate statistical analysis,including arginine,calycosin,ononin,formononetin,and astragalosideⅣ,most of which were observed to be accumulated in PG samples except for astragalosideⅣ.Then,we performed machine learning on the quantification data of five compounds and constructed a logistic regression prediction model.Finally,the external validation in an independent validation set of AR(n=20 batches)verified that the five compounds,as well as the model,had strong capability to distinguish the two grades of AR,with the prediction accuracy>90%.Our findings present a panel of meaningful candidate markers that would significantly catalyze the innovation in AR grading. | Xinyue Yu Jingxue Nai Huimin Guo Xuping Yang Xiaoying Deng Xia Yuan Yunfei Hua Yuan Tian Fengguo Xu Zunjian Zhang Yin Huang | 2021 | Journal of Pharmaceutical Analysis2021,11,5: | 2 |
| 19 | The E Protein Is a Multifunctional Membrane Protein of SARS-CoV显示文摘The E (envelope) protein is the smallest structural protein in all coronaviruses andis the only viral structural protein in which no variation has been detected. Weconducted genome sequencing and phylogenetic analyses of SARS-CoV. Based ongenome sequencing, we predicted the E protein is a transmembrane (TM) pro-tein characterized by a TM region with strong hydrophobicity and α-helix con-formation. We identified a segment (NH2-_L-Cys-A-Y-Cys-Cys-N_-COOH) in thecarboxyl-terminal region of the E protein that appears to form three disulfide bondswith another segment of corresponding cysteines in the carboxyl-terminus of the S(spike) protein. These bonds point to a possible structural association between theE and S proteins. Our phylogenetic analyses of the E protein sequences in all pub-lished coronaviruses place SARS-CoV in an independent group in Coronaviridaeand suggest a non-human animal origin. | QingfaWu YilinZhang HongLu JingWang XimiaoHe YongLiu ChenYe WeiLin JianfeiHu JiaJi JingXu JiaYe YongwuHu WenjunChen SonggangLi JunWang JiauWang ShengliBi HuanmingYang | 2003 | Genomics, Proteomics & Bioinformatics2003,1,2: | 2 |
| 20 | Simplified purification method for Clostridium difficile toxin A显示文摘AIM: To establish the purification method for Clostridium difficile ( C. difficile) toxin A.METHODS: C. difficile VPI 10463 filtrate was cultured anaerobically by the dialysis bag methods. And then the toxin A was purified by precipitation with 500 g/L (NH4)2SO4 and acid precipitation at pH 5.5, followed by ion-exchange chromatography on DEAE-Toyopearl.RESULTS: Purified toxin A exhibited only one band on native polyacrylamide gel electrophoresis (native-PAGE) and Ouchterlony double immunodiffusion. The molecular weight of toxin A was estimated to be 550 000. The purified toxin A had a protein concentration of 0.881 mg/mL. The minimum lethal dose was 1×10^6 MLD/mL (i.p.mice). The cytotoxic titer was 10^7 CU/mg. The haemagglutinate activity was at a concentration of 1.72 μg/mL. The ratio of fluid volume (mL) accumulated to the length (cm) of the loop was 2.46.CONCLUSION: The modified method for purification of toxin A of C difficile was simple and convenient. It may be even more suitable for purification of toxin A on large scales. | Si-WuFu JingXue Ya-LiZhang Dian-YuanZhou | 2004 | World Journal of Gastroenterology2004,10,18: | 2 |