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310篇 您的检索式:作者名="Changfeng"
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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
2Anaerobic microbiologically influenced corrosion mechanisms interpreted using bioenergetics and bioelectrochemistry: A review显示文摘Microbiologically influenced corrosion(MIC) is a major cause of corrosion damages, facility failures, and financial losses, making MIC an important research topic. Due to complex microbiological activities and a lack of deep understanding of the interactions between biofilms and metal surfaces, MIC occurrences and mechanisms are difficult to predict and interpret. Many theories and mechanisms have been proposed to explain MIC. In this review, the mechanisms of MIC are discussed using bioenergetics, microbial respiration types, and biofilm extracellular electron transfer(EET). Two main MIC types, namely EET-MIC and metabolite MIC(M-MIC), are discussed. This brief review provides a state of the art insight into MIC mechanisms and it helps the diagnosis and prediction of occurrences of MIC under anaerobic conditions in the oil and gas industry.Yingchao Li Dake Xu Changfeng Chen Xiaogang Li Ru Jia Dawei Zhang Wolfgang Sand Fuhui Wang Tingyue Cu 2018Journal of Materials Science & Technology2018,34,10:43
3Evaluation 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
4In 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
5Geochronology, 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
6Altered regional homogeneity in post-traumatic stress disorder: a resting-state functional magnetic resonance imaging study显示文摘Objective Little is known about the brain systems that contribute to vulnerability to post-traumatic stress disorder (PTSD). Comparison of the resting-state patterns of intrinsic functional synchronization, as measured by functional magnetic resonance imaging (fMRI), between groups with and without PTSD following a traumatic event can help identify the neural mechanisms of the disorder and targets for intervention. Methods Fifty-four PTSD patients and 72 matched traumatized subjects who experienced the 2008 Sichuan earthquake were imaged with blood oxygen level-dependent (BOLD) fMRI and analyzed using the measure of regional homogeneity (ReHo) during the resting state. Results PTSD patients presented enhanced ReHo in the left inferior parietal lobule and right superior frontal gyrus, and reduced ReHo in the right middle temporal gyrus and lingual gyrus, relative to traumatized individuals without PTSD. Conclusion Our findings showed that abnormal brain activity exists under resting conditions in PTSD patients who had been exposed to a major earthquake. Alterations in the local functional connectivity of cortical regions are likely to contribute to the neural mechanisms underlying PTSD.Yan Yin Changfeng Jin Lisa T. Eyler Hua Jin Xiaolei Hu Lian Duan Huirong Zheng Bo Feng Xuanyin Huang Baoci Shan Qiyong Gong Lingjiang Li 2012Neuroscience Bulletin2012,28,5:9
7Surface integrity and fatigue behavior when turning γ-TiAl alloy with optimized PVD-coated carbide inserts显示文摘This paper presents a comprehensive investigation on the effects of tool and turning parameters on surface integrity and fatigue behavior in turning c-Ti Al alloy. The wear of inserts surface, cutting forces, and surface roughness were studied to optimize PVD-coated carbide inserts.Surface topography, residual stresses, microhardness, and microstructure were analyzed to characterize the surfaces layer under different turning parameters. Surface integrity and fatigue life tests of c-Ti Al alloy were conducted under turning and turning-polishing processes. The results show that compared to CNMG120412-MF4, CNMG120408-SM is more suitable because it obtained low cutting force, surface roughness, and tool wear. With increasing the cutting speed and depth, the depths of the compressive residual stress layer, hardening layer, and plastic deformation layer increased. For turning and turning-polishing specimens, the compressive residual stress was relaxed by less than 20%–30% after 10~7 cycles. The fatigue life of a turning-polishing specimen with R_a= 0.15 mm has increased 3 times from that of a turning specimen with R_a= 0.43 mm.Changfeng YAO Jiannan LIN Daoxia WU Junxue REN 2018Chinese Journal of Aeronautics2018,31,4:9
8Multi-quasiparticle rotational bands in neutron-rich erbium isotopes显示文摘Multi-quasiparticle states and rotational bands in neutron-rich erbium isotopes have been investigated by the configuration-constrained pairing-deformation-frequency self-consistent total-Routhian-surface (TRS) method with particle-number-conserved pairing. Specifically, the recently observed Kn=4-bands in 168,170,172 Er have been found to experience a configuration change in our calculation. Some other multi-quasiparticle states with uncertain configuration assignments have been reinvestigated by calculating their collective rotations. The configuration-constrained TRS calculation can reproduce experimental data consistently.FU XiMing JIAO ChangFeng XU FuRong ZHANG ZhenHua 2013Science China(Physics,Mechanics & Astronomy)2013,56,8:8
9Removal of dust from flue gas in magnetically stabilized fluidized bed显示文摘A magnetically stabilized fluidized bed(MSFB, 500 mm×2100 mm) was designed to study dust removal from flue gas.Based on the mechanism of dust removal in a fixed bed,the effects on collection efficiency of magnetic field intensity,ratio of flue gas velocity to minimum fluidization velocity,bed height,and particle average diameter,were investigated.Then feasible methods for MSFB to better remove dust were proposed.Over 95% of dust removal with MSFB can be achieved,when stable fluidization is maintained and when magnetic particles are frequently renewed.Yinghui Wang Keting Gui Mingheng Shi Changfeng Li 2008Particuology2008,6,2:8
10The 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
11Investigation 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
12NIR-IIb excitable bright polymer dots with deep-red emission for in vivo through-skull three-photon fluorescence bioimaging显示文摘It is of great significance to study the brain structure and function in deep-tissue for neuroscience research and bio-medical applications because of the urgent demand for precise theranostics.Three-photon fluorescence microscopic(3PFM)bioimaging excited by the light in near-infrared IIb(NIR-IIb,1,500–1,700 nm)spectral region is one of the most promising imaging techniques with the advantages of high spatial resolution,large imaging depth,and reduced scattering.Herein,a type of NIR-IIb light excitable deep-red emissive semiconducting polymer dots(P-dots)with bright 3PF and large three-photon absorption cross-section(σ3)at 1,550 nm was prepared.Then the P-dots were functionalized with polystyrene polymer polystyrene graft ethylene oxide functionalized with carboxyl groups(PS-PEG-COOH)and modified with NH2-poly(ethylene glycol)(PEG)to synthesis photochemically stable and biocompatible P-dots nanoparticles(NPs).Further the P-dots NPs were utilized for in vivo 3PFM bioimaging of cerebral vasculature with and without the brain skull under 1,550 nm femtosecond(fs)laser excitation.In vivo 3PFM bioimaging of the mice cerebral vasculature at various vertical depths was obtained.Moreover,a vivid three-dimensional structure of the mice vascular architecture beneath the skull was reconstructed.At the depth of 350μm beneath the brain skull,3.8μm blood vessels could still be clearly recognized.NIR-IIb excitable P-dots assisted 3PFM bioimaging has great potential in accurate deep tissue bioimaging.Nuernisha Alifu Abudureheman Zebibula Hequn Zhang Huwei Ni Liang Zhu Wang Xi Yalun Wang Xueliang Zhang Changfeng Wu Jun Qian 2020Nano Research2020,13,10:6
13Corrosion behavior of Al_(0.4)CoCu_(0.6)NiSi_(0.2)Ti_(0.25) high-entropy alloy coating via 3D printing laser cladding in a sulphur environment显示文摘High-entropy alloys(HEAs) are of great interest in materials science and engineering communities owing to their unique phase structure.HEAs are constructed with five or more principal alloying elements in equimolar or near-equimolar ratios.Therefore,they can derive their performance from multiple principal elements ratherthan a single element.In this work,three-dimensional printing laser cladding was applied to produce an Al_(0.4)CoCu_(0.6)NiSi_(0.2)Ti_(0.25) HEA coating.The experimental results confirmed that the laser cladding could be used to produce a thin coating of 120 μm in thickness.In the high-temperature laser cladding process,some Fe elements diffused from the substrate to the coating,forming a combination of face-centred cubic and body-centred cubic phase structures.The HEA coating metallurgically bonded well with the substrate.Owing to the increased dislocation density and number of grain boundaries,the HEA coating was harder and had a stronger hydrophobicity than X70 steel.The electrochemistry results showed that the HEA coating had better corrosion resistance than X70 steel.Aluminium oxides formed on the surface of the HEA coating had a certain protective effect.However,because of the laser cladding,the HEA coating generated cracks.In future work,the laser cladding technology will be improved and heat treatment will be implemented to prevent formation of cracks.Hongxia Wan Dongdong Song Xiaolei Shi Yong Cai Tingting Li Changfeng Chen 2021Journal of Materials Science & Technology2021,,1:6
14Heterogeneously supported pseudo-single atom Pt as sustainable hydrosilylation catalyst显示文摘Huachao Zai Yizhou Zhao Shanyu Chen Lei Ge Changfeng Chen Qi Chen Yujing Li 2018Nano Research2018,11,5:6
15Isolation via enrichment and characterization of ten polymorphic microsatellite loci in the cuttlefish, Sepiella maindroni de Rochebruns显示文摘Ten novel polymorphic microsatellite loci were developed using an enrichment and colony hybridization protocol and characterized for the cuttlefish,Sepiella maindroni.Polymorphism was explored by using 30 individuals from the coastal waters of Zhanjiang,Guangdong province,China,in December 2007.The number of alleles ranged from 5 to 13.The ranges of observed and expected heterozygosity were from 0.578 9 to 1.000 0 and 0.682 8 to 0.925 7,respectively,and the average polymorphic information content (P IC) was 0.778 5.These microsatellite loci will certainly facilitate the detection of the genetic variation and population structure of S.maindroni.WU Changwen CHI Changfeng HE Guangyuan LU Zhenming XU Meiying 2010Acta Oceanologica Sinica2010,29,6:6
16Competition between collective oblate rotation and non-collective prolate K isomerism in neutron-rich tungsten isotopes显示文摘Recent experiments open up the possibility to investigate oblate rotation-aligned states and prolate high-K isomers in neutron-rich tungsten isotopes.In the present work,we perform the projected-shell-model calculations for A ~ 190 tungsten nuclei.The 190 W results are compared with experimental data.The observed 8 + isomer is assigned as a two-quasiproton K π = 8 + configuration.Low-lying high-K four-quasiparticle states are predicted.Of particular interest is the prediction of the K π = 20 + state in 190,192 W,which may form a long-lived spin trap.In competition with the prolate high-K states,rotational alignment leads to near-yrast collective oblate rotation.JIAO ChangFeng SHI Yue XU FuRong SUN Yang WALKER P M 2012Science China(Physics,Mechanics & Astronomy)2012,55,9:5
17Indole-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
18PtxCuy nanocrystals with hexa-pod morphology and their electrocatalytic performances towards oxygen reduction reaction显示文摘二金属的磅 x 有明确的昆虫形态学的 Cu y nanocrystals (NC ) 经由一条湿化学途径被综合。有约 20 nm 表演的尺寸的同样综合的凸的 NC 暴露了低索引(111 ) 种子上的方面和豆荚上的各种各样的高索引的方面。生长机制沿着 cuboctahedral 上的结晶的方向播种的 <100> 包含了比较喜欢的生长。合成协议能被用于磅 x 有各种各样的 Cu/Pt 比率的 Cu y NC。向氧减小反应(ORR ) 在碳黑色上支持的昆虫 PtxCuy NC 的电镀物品催化的活动被学习。昆虫 PtCu 2/C 催化剂展出最高特定的活动(3.7 妈 / 厘米 2) 和集体活动(2.4 A/mg ) 报导了为磅 x Cu y 。有磅 x Cu y 显示提高的活动从词法因素发源。豆荚上的高索引的方面以及丰富的边和步的存在能相当解释提高的催化活动。昆虫磅 x Cu y /C 催化剂也在加速的耐久性测试以后显示出高词法的稳定性和活动。同样综合的昆虫磅 x Cu y NC 为质子交换膜燃料房间作为阴极电镀物品催化剂有高潜力。Yujing Li Fanxin Quan Enbo Zhu Lin Chen Yu Huang Changfeng Chen 2015Nano Research2015,8,10:5
19Innovation and development of BeiDou Navigation Satellite System(BDS)project management mode显示文摘The BeiDou Navigation Satellite System(hereinafter referred to as BDS)has been independently developed and operated by China with an eye on the needs of the country’s national security as well as economic and social development.As a temporal-spatial infrastructure of national significance,the BDS provides all-time,all-weather and high-accuracy positioning,navigation and timing services to global users.Changfeng YANG 2021Frontiers of Engineering Management2021,8,2:4
20Heat transfer enhancement in a tube fitted with helical blade rotors with grooves显示文摘Zhen Zhang Weimin Yang Changfeng Guan Yumei Ding Hua Yan 2013Experimental Thermal and Fluid Science2013,,:4
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