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44篇 您的检索式:作者名="Changfeng Liu"
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1A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
2Evaluation of measurement uncertainty based on grey system theory for small samples from an unknown distribution显示文摘To evaluate measurement uncertainty for small sample size and measurement data from an unknown distribution, we propose a grey evaluation method of measurement uncertainty based on the grey relation coefficient. The uncertainty of measurement is analyzed using grey system theory, and the defects of the grey evaluation model of measurement uncertainty (GEMU) are studied. We then establish an improved grey evaluation model of measurement uncertainty (IGEMU). Simulations show that the precision of IGEMU is greater than that of GEMU, and that sample size has only a small effect on the precision of IGEVU. In particular, IGEMU is applied to evaluating measurement uncertainty for small sample size and measurement data from an unknown distribution. The measurement uncertainty of total profile deviation, which is measured by the CNC gear measuring center, can be evaluated by a combination of IGEMU and the Monte Carlo method.HAN LianFu TANG WenYan LIU YongMeng WANG Jun FU ChangFeng 2013Science China(Technological Sciences)2013,56,6:18
3In vivo theranostics with near-infraredemitting carbon dots—highly efficient photothermal therapy based on passive targeting after intravenous administration显示文摘Carbon dots that exhibit near-infrared fluorescence(NIR CDs)are considered emerging nanomaterials for advanced biomedical applications with low toxicity and superior photostability and targeting compared to currently used photoluminescence agents.Despite progress in the synthesis of NIR CDs,there remains a key obstacle to using them as an in vivo theranostic agent.This work demonstrates that the newly developed sulfur and nitrogen codoped NIR CDs are highly efficient in photothermal therapy(PTT)in mouse models(conversion efficiency of 59%)and can be readily visualized by photoluminescence and photoacoustic imaging.The real theranostic potential of NIR CDs is enhanced by their unique biodistribution and targeting.Contrary to all other nanomaterials that have been tested in biomedicine,they are excreted through the body’s renal filtration system.Moreover,after intravenous injection,NIR CDs are accumulated in tumor tissue via passive targeting,without any active species such as antibodies.Due to their accumulation in tumor tissue without the need for intratumor injection,high photothermal conversion,excellent optical and photoacoustic imaging performance,and renal excretion,the developed CDs are suitable for transfer to clinical biomedical practice.Xin Bao Ye Yuan Jingqin Chen Bohan Zhang Di Li Ding Zhou Pengtao Jing Guiying Xu Yingli Wang Kateřina Holá Dezhen Shen Changfeng Wu Liang Song Chengbo Liu Radek Zbořil Songnan Qu 2018Light(Science & Applications)2018,7,1:13
4Geochronology, Geochemistry and Tectonic Significance of the Early Carboniferous Gabbro and Diorite Plutons in West Ujimqin, Inner Mongolia显示文摘Early Carboniferous gabbros and diorites are distributed in West Ujimqin, Inner Mongolia. The LA-ICP-MS zircon U-Pb ages of the gabbro and diorite samples are 321± 2 Ma(MSWD=0.65) and 319.4± 1.5 Ma(MSWD=0.42), respectively. In addition, new geochemistry data from three gabbro and three diorite samples are presented. All six samples show high Al_2O_3 contents but low-TiO_2 contents, belonging to tholeiitic and calc-alkali basalt series. All of the samples have similar chondrite normalized REE patterns characterized by moderate depletion in LREE similar to normal middle oceanic ridge basalt(MORB). The MORB and PM-normalized trace element patterns show the enrichment in large ion lithophile elements(LILE, e.g., Rb, Ba and Sr), depletion in high field strength elements(HFSE) and distinctly negative Nb and Ta anomalies similar to volcanic arc basalt. Furthermore, as shown in the correlation plots of La/Ba vs. La/Nb, Ba/La vs. Ce/Pb, Th/La vs. Ce/Pb, Nb/La vs. Ba/Rb, and Nb/Y vs. La/Yb, the magma source has underwent contamination and metasomatism from the subduction fluid. According to the Zr/Nb, La/Nb, and La/Ta ratios and the Nb/Y vs. Zr/Y and Sm/Yb vs. La/Sm diagrams, the magma was derived from shallow depleted lithospheric mantle and formed by moderate(5%~20%) partial melting of spinel lherzolites. Tectonic setting discrimination diagrams reveal that the gabbros and diorites display both characteristics of MORB and volcanic arc basalt, which is consistent with their geochemical characteristics. On the basis of the geochemical features of these samples, combined with regional geological data and many previous researches in the study area, the Early Carboniferous gabbros and diorites of West Ujimqin are suggested to be formed in an intensely extensional rift setting, and a limited immature ocean basin probably formed after subsequent development.Shiwei Ma Changfeng Liu Zhiqin Xu Zhiguang Zhou Jinyuan Dong Hongying Li 2017Journal of Earth Science2017,28,2:10
5The 600-mm precipitation isoline distinguishes tree-ring-width responses to climate in China显示文摘The numerous temperature and precipitation reconstructions in China based on tree-ring-width data have played significant roles in furthering the understanding of past climate changes. However, the geographical variability in the responses of trees to climate variations in China remains largely undetermined. Here, we describe an important spatial boundary in the response of trees to climate variations, namely the 600-mm annual precipitation isoline. We found that, to the north of this line, tree-ring widths are usually positively correlated with precipitation and negatively correlated with growing-season temperature. To the south of this line, the tree-ring widths respond positively to temperature, and winter half-year temperatures are the main reconstructed parameters, especially on the third topographical step of China. We also found that precipitation reconstructions based on tree-ring data and the Palmer Drought Severity Index almost exclusively fall in the region of the 200- to 600-mm annual precipitation isolines, not other regions. Our findings indicate that, when using multiple tree-ring-width chronologies for large-scale past climate reconstructions, the climatic signal of each tree-ring-width series should be carefully considered.Yu Liu Huiming Song Changfeng Sun Yi Song Qiufang Cai Ruoshi Liu Ying Lei Qiang Li 2019National Science Review2019,6,2:8
6Investigation of octupole effects in superheavy nuclei with improved potential-energy-surface calculations显示文摘It has been found that high-order deformation (e.g.β6) can have important effects on the structures of superheavy nuclei. In the present work, we investigate octupole deformation effects on superheavy nuclei with an improved potential-energy-surface (PES) calculation by including reflection-asymmetric deformations in a space of (β2 ,β3 ,β4 , β5). The calculations give various deformations including highly deformed (β2 ≈ 0.4) and superdeformed (β2 ≈ 0.7) shapes. The octupole-deformation degree of freedom mainly affects the fission barrier beyond the second minimum of PES.WANG HuaLei LIU HongLiang XU FuRong JIAO ChangFeng 2012Chinese Science Bulletin2012,57,15:7
7Indole-3-propionic Acid-aggravated CCl_(4)-induced Liver Fibrosis via the TGF-β1/Smads Signaling Pathway显示文摘Background and Aims:The pathogenesis of liver fibrosis involves liver damage,inflammation,oxidative stress,and intestinal dysfunction.Indole-3-propionic acid(IPA)has been demonstrated to have antioxidant,anti-inflammatory and anticancer activities,and a role in maintaining gut homeostasis.The current study aimed to investigate the role of IPA in carbon tetrachloride(CCl4)-induced liver fibrosis and explore the underlying mechanisms.Methods:The liver fibrosis model was established in male C57BL/6 mice by intraperitoneal injection of CCl4 twice weekly.IPA intervention was made orally(20 mg/kg daily).The degree of liver injury and fibrosis were assessed by serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),and histopathology.Enzyme-linked immunosorbent assay and quantitative real-time polymerase chain reaction(qPCR)were used to detect the inflammatory cytokines.The malondialdehyde(MDA),glutathione,glutathione peroxidase,superoxide dismutase,and catalase were determined via commercial kits.Hepatocyte apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay.The expression of mRNA and protein was assayed by qPCR,Western blotting,or immunohistochemical staining.Results:After IPA treatment,the ALT and AST,apoptotic cells,and pro-inflammatory factor levels were enhanced significantly.Moreover,IPA intervention up-regulated the expression of collagen I,α-smooth muscle actin,tissue inhibitor of matrix metalloproteinase-1,matrix metalloproteinase-2,transforming growth factor-β1(TGF-β1),Smad3,and phosphorylated-Smad2/3.Additionally,IPA intervention did not affect the MDA level.Attractively,the administration of IPA remodeled the gut flora structure.Conclusions:IPA aggravated CCl_(4)-induced liver damage and fibrosis by activating HSCs via the TGF-β1/Smads signaling pathway.Fei Liu Changfeng Sun Yuanfang Chen Fei Du Yuxiang Yang Gang Wu 2021Journal of Clinical and Translational Hepatology2021,9,6:5
8SETD8 induces stemness and epithelial–mesenchymal transition of pancreatic cancer cells by regulating ROR1 expression显示文摘Pancreatic cancer(PC)is one of the most deadly diseases,and its incidence is increasing year by year.The methyltransferase SETD8 has been demonstrated to play an important role in tumor cell proliferation and metastasis.However,little is known about whether SETD8 could affect the invasion and metastasis of PC and the mechanism underlying the regulation.Based on our previous report,here,we further found that SETD8 could promote the invasion and migration of PC cells by inducing the expression of receptor tyrosine kinase-like orphan receptor 1(ROR1).ROR1 was predominantly upregulated in PC tissues and was correlated with lymph node metastasis and worse prognosis.Mechanistically,SETD8 mediated ROR1 activity and regulated PC cells invasion and migration,although promoting the expression of stemness and epithelial–mesenchymal transition-related molecules.This promotion effect disappeared when the catalytically inactive mutant SETD8 was overexpressed,which could be counteracted by the SETD8-specific methyltransferase inhibitor UNC0379.Collectively,our results demonstrate that SETD8 may be a novel prognostic factor and a therapeutic target of PC.Mengqi Liu Yihua Shi Qiangsheng Hu Yi Qin Shunrong Ji Wensheng Liu Qifeng Zhuo Guixiong Fan Zeng Ye Changfeng Song Xianjun Yu Xiaowu Xu Wenyan Xu 2021Acta Biochimica et Biophysica Sinica2021,53,12:2
9The complete genome of hydrocarbon-degrading Pseudoalteromonas sp. NJ289 and its phylogenetic relationship显示文摘Genus Pseudoalteromonas belongs to Family Pseudoalteromonadaceae in Gammaproteobacteria. A cold-adapted gram-negative bacterium, hydrocarbon-degrading Pseudoalteromonas sp. NJ289, was isolated from sea-ice of the Antarctica region, and sequenced the whole genome through the next generation sequencing platform. The assembly yielded three contigs representing two chromosomes and one plasmid with the sizes of 3.2 Mb, 636 kb and 1.8 kb, respectively. The G+C contents of genome were 40.83% and included 3 589 ORFs. Functional annotation indicated some potential roles in enzymatic activity and environmental adaptability. This study may help for understanding the population diverse, evolutionary ecology and the microbial interaction.LIU Fangming WANG Yibin QU Changfeng ZHENG Zhou MIAO Jinlai XU Hua XIAO Tian 2017Acta Oceanologica Sinica2017,36,2:2
10Assessment of Fiber Distribution in Steel Fiber Mortar Using Image Analysis显示文摘A new test method was introduced to measure fiber distribution in steel fiber reinforced mortar by using image analysis technique. Through specimen preparation, image acquisition, fiber extraction, and measurement of related fiber parameters, quantitative analysis of fiber distribution could be obtained by two parameters, namely dispersion coefficient and orientation factor. Effect of boundaries, size and steel fiber content on fiber distribution was discussed. Results showed that, steel fiber distribution was affected by boundary effect, which would be weakened with the increase of specimen size. If the length and width remained constant, the specimen height had a significant effect on orientation factor of fiber, while its influence on dispersion coefficient was not so obvious. With the increase of steel fiber content, dispersion coefficient decreased slightly, and orientation factor deviated from 0.5.刘建忠 孙伟 MIAO Changwen LIU Jiaping LI Changfeng 2012Journal of Wuhan University of Technology(Materials Science)2012,27,1:2
11Carboniferous ridge subduction in the Xingmeng Orogenic Belt:Constraints from geochronological,geochemical,and Sr-Nd-Hf isotopic analysis of strongly peraluminous granites and gabbro-diorites in the Xilinhot micro-continent显示文摘The Xingmeng Orogenic Belt evolved through a long-lived orogeny involving multiple episodes of subduction and accretion.However,there is a debate on its tectonic evolution during the Late Paleozoic.Here,we report geochemical,geochronological,and isotopic data from strongly peraluminous granites and gabbro-diorites from the Sunidzuoqi-Xilinhot region.Zircon U-Pb ages suggest that the intrusive rocks were emplaced during the Early Carboniferous(333-322 Ma).The granites exhibit geochemical characteristics similar to S-type granites,with high SiO_(2)(72.34-76.53 wt.%),Al_(2)O_(3)(12.45-14.65 wt.%),and A/CNK(1.07-1.16),but depleted Sr,Nb,and Ta contents.They exhibit positiveε_(Nd)(t)andε_(Hf)(t)values(-0.3 to 2.8 and 2.7-5.7,respectively)and young Nd and Hf model ages(T_(DM2)(Nd)=853-1110 Ma and T_(DM2)(Hf)=975-1184 Ma),suggesting that they may be the partial melting products of heterogeneous sources with variable proportions of pelite,psammite,and metabasaltic rocks.The meta-gabbro-diorites from the Maihantaolegai pluton have low SiO_(2)(47.06-53.49 wt.%)and K_2O(0.04-0.99 wt.%)contents,and demonstrate slight light rare earth element(REE)depletion in the chondritenormalized REE diagrams.They have high zirconε_(Hf)(t)values(14.41-17.34)and young Hf model ages(T_(DM2)(Hf)=230-418 Ma),indicating a more depleted mantle source.The variations of the Sm/Yb and La/Sm ratios can thus be used to assess the melting degree of the mantle source from 5%to 20%,suggesting a quite shallow mantle melting zone.We propose that the petrogenesis and distribution of the strongly peraluminous granites and gabbro-diorites,as well as the tectonic architecture of the region,can be explained by a ridge subduction model.Based on these results,and previous studies,we suggest a southward ridge subduction model for the Sunidzuoqi-Xilinhot region.Changfeng Liu Zhiguang Zhou Guosheng Wang Chen Wu Hongying Li Shiwei Ma 2021Geoscience Frontiers2021,12,3:2
12Surface defect-rich ceria quantum dots anchored on sulfur-doped carbon nitride nanotubes with enhanced charge separation for solar hydrogen production显示文摘Designing defect-engineered semiconductor heterojunctions can effectively promote the charge carrier separation.Herein,novel ceria(CeO2) quantum dots(QDs) decorated sulfur-doped carbon nitride nanotubes(SCN NTs) were synthesized via a thermal polycondensation coupled in situ depositionprecipitation method without use of template or surfactant.The structure and morphology studies indicate that ultrafine CeO2 QDs are well distributed inside and outside of SCN NTs offering highly dispersed active sites and a large contact interface between two components.This leads to the promoted formation of rich Ce^(3+) ion and oxygen vacancies as confirmed by XPS.The photocatalytic performance can be facilely modulated by the content of CeO2 QDs introduced in SCN matrix while bare CeO2 does not show activity of hydrogen production.The optimal catalyst with 10% of CeO2 loading yields a hydrogen evolution rate of 2923.8 μmol h-1 g-1 under visible light,remarkably higher than that of bare SCN and their physical mixtures.Further studies reveal that the abundant surface defects and the created 0 D/1 D junctions play a critical role in improving the separation and transfer of charge carriers,leading to superior solar hydrogen production and good stability.Mengru Li Changfeng Chen Liping Xu Yushuai Jia Yan Liu Xin Liu 2021Journal of Energy Chemistry2021,30,1:1
13Differential HSP70 expression in Mytilus coruscus under various stressors 显示文摘LIU Huihui HE Jianyu CHI Changfeng 2014Gene2014,543,1:1
14Studies on Fragrance Raw Materials of α-Terpineol Analogues显示文摘Thirty four α-substituted or α, α-disubstituted-( 1-methylcyclohexen-4-yl )methanols and α-substituted or α,α-disubstituted-(4-methylcyclohexyl) methanols weresynthesized. Thirty two of them are new compounds. 1H NMR and IR spectra of allthe compounds were determined, MS spectra of some of them were obtained as well.The characteristic odors were evaluated.Keywords Fragrance raw materials,α-Terpineol analogues, Synthesis,Tang Shixiong, Liu Hong, Wang Changfeng, Cao Yurong, Liao Xiangmin and Wang Xiaolan (Department of Chemistry, Nankai University, Tianjin) 1991Chemical Research in Chinese Universities1991,7,4:1
15Direct H-He chemical association in superionic FeO_(2)H_(2)He at deep-Earth conditions显示文摘Hydrogen and helium are known to play crucial roles in geological and astrophysical environments;however,they are inert toward each other across wide pressure-temperature(P-T)conditions.Given their prominent presence and influence on the formation and evolution of celestial bodies,it is of fundamental interest to explore the nature of interactions between hydrogen and helium.Using an advanced crystal structure search method,we have identified a quaternary compound FeO_(2)H_(2)He stabilized in a wide range of P-T conditions.Ab initio molecular dynamics simulations further reveal a novel superionic state of FeO_(2)H_(2)He hosting liquid-like diffusive hydrogen in the FeO_(2)He sublattice,creating a conducive environment for H-He chemical association,at P-T conditions corresponding to the Earth’s lowest mantle regions.To our surprise,this chemically facilitated coalescence of otherwise immiscible molecular species highlights a promising avenue for exploring this long-sought but hitherto unattainable state of matter.This finding raises strong prospects for exotic H-He mixtures inside Earth and possibly also in other astronomical bodies.Jurong Zhang Hanyu Liu Yanming Ma Changfeng Chen 2022National Science Review2022,9,7:1
16Facile and Versatile Preparation of Silicate-1 Hollow Structures Using Cotton Threads as Templates显示文摘Liu Weiwei Zeng Changfeng Zhang Lixiong 2007Mater Chem Phys2007,103,23:1
17Collaborative manufacturing technologies of structure shape and surface integrity for complex thin-walled components of aero-engine:Status,challenge and tendency显示文摘Presently,the service performance of new-generation high-tech equipment is directly affected by the manufacturing quality of complex thin-walled components.A high-efficiency and quality manufacturing of these complex thin-walled components creates a bottleneck that needs to be solved urgently in machinery manufacturing.To address this problem,the collaborative manufacturing of structure shape and surface integrity has emerged as a new process that can shorten processing cycles,improve machining qualities,and reduce costs.This paper summarises the research status on the material removal mechanism,precision control of structure shape,machined surface integrity control and intelligent process control technology of complex thin-walled components.Numerous solutions and technical approaches are then put forward to solve the critical problems in the high-performance manufacturing of complex thin-wall components.The development status,challenge and tendency of collaborative manufacturing technologies in the high-efficiency and quality manufacturing of complex thin-wall components is also discussed.Biao ZHAO Wenfeng DING Zhongde SHAN Jun WANG Changfeng YAO Zhengcai ZHAO Jia LIU Shihong XIAO Yue DING Xiaowei TANG Xingchao WANG Yufeng WANG Xin WANG 2023Chinese Journal of Aeronautics2023,36,7:1
18Prediction of hot deformation behavior in Ni-based alloy considering the effect of initial microstructure显示文摘High temperature heat treatments were conducted for as-cast N08028 alloy to obtain various microstructures with different amounts of σ-phase,and then hot compression tests were carried out using Gleeble-3500 thermo-mechanical simulator in deformation temperature range from 1100 to1200 ℃ and strain rate range from 0.01 to 1 s-1. For the same initial microstructure, the flow stress was observed to increase with increasing the strain rate and decreasing the deformation temperature, while for the same deformation condition, the flow stress was found to increase with increasing the amount of σ-phase in the initial microstructure. Moreover, dynamic recrystallization was found to be the main dynamic soften mechanism. On this basis, Arrhenius-type constitutive equations and artificial neural network(ANN) model with back-propagation learning algorithm were established to predict hot deformation behavior of the alloy. Furthermore, the parameters of constitutive equations were found to be dependent on the initial microstructure, which was also as one of the inputs for the ANN model. Suitability of the two models was evaluated by comparing the accuracy, correlation coefficient and average absolute relative error, of the prediction. It is concluded that the ANN model is more accurately than the constitutive equations.Qiang Zuo Feng Liu Lei Wang Changfeng Chen Zhonghua Zhang 2015Progress in Natural Science:Materials International2015,25,1:1
19Microstructure and properties of Ti C-Fe cermet coatings by reactive flame spraying using asphalt as carbonaceous precursor显示文摘Liu Huiyuan Huang Jihua Yin Changfeng 2007Ceramics International2007,33,:1
20One-step smoothing Newton method for solving the mixed complementarityproblem with a Po -function 显示文摘Tang Jia Liu Sanyang? Ma Changfeng 2009Applied Mathematics and Computation?2009,215,6:1
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