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112篇 您的检索式:作者名="Yuqing Xu"
    题名 作者 年代 出处 被引量
1Transmission routes of 2019-nCoV and controlsin dental practice显示文摘A novel β-coronavirus(2019-nCoV) caused severe and even fatal pneumonia explored in a seafood market of Wuhan city, Hubei province, China, and rapidly spread to other provinces of China and other countries. The 2019-nCoV was different from SARS-Co V,but shared the same host receptor the human angiotensin-converting enzyme 2(ACE2). The natural host of 2019-nCoV may be the bat Rhinolophus affinis as 2019-nCoV showed 96.2% of whole-genome identity to Bat Co V Ra TG13. The person-to-person transmission routes of 2019-nCoV included direct transmission, such as cough, sneeze, droplet inhalation transmission, and contact transmission, such as the contact with oral, nasal, and eye mucous membranes. 2019-nCoV can also be transmitted through the saliva, and the fecal–oral routes may also be a potential person-to-person transmission route. The participants in dental practice expose to tremendous risk of 2019-nCoV infection due to the face-to-face communication and the exposure to saliva, blood, and other body fluids, and the handling of sharp instruments. Dental professionals play great roles in preventing the transmission of2019-nCoV. Here we recommend the infection control measures during dental practice to block the person-to-person transmission routes in dental clinics and hospitals.Xian Peng Xin Xu Yuqing Li Lei Cheng Xuedong Zhou Biao Ren 2020International Journal of Oral Science2020,12,1:29
2Satellite range scheduling with the priority constraint: An improved genetic algorithm using a station ID encoding method显示文摘Satellite range scheduling with the priority constraint is one of the most important problems in the field of satellite operation.This paper proposes a station coding based genetic algorithm to solve this problem,which adopts a new chromosome encoding method that arranges tasks according to the ground station ID.The new encoding method contributes to reducing the complexity in conflict checking and resolving,and helps to improve the ability to find optimal resolutions.Three different selection operators are designed to match the new encoding strategy,namely random selection,greedy selection,and roulette selection.To demonstrate the benefits of the improved genetic algorithm,a basic genetic algorithm is designed in which two cross operators are presented,a single-point crossover and a multi-point crossover.For the purpose of algorithm test and analysis,a problem-generating program is designed,which can simulate problems by modeling features encountered in real-world problems.Based on the problem generator,computational results and analysis are made and illustrated for the scheduling of multiple ground stations.Li Yuqing Wang Rixin Liu Yu Xu Minqiang 2015Chinese Journal of Aeronautics2015,28,3:22
3Rescheduling of observing spacecraft using fuzzy neural network and ant colony algorithm显示文摘This paper aims at rescheduling of observing spacecraft imaging plans under uncertainties. Firstly, uncertainties in spacecraft observation scheduling are analyzed. Then, considering the uncertainties with fuzzy features, this paper proposes a fuzzy neural network and a hybrid rescheduling policy to deal with them. It then establishes a mathematical model and manages to solve the rescheduling problem by proposing an ant colony algorithm, which introduces an adaptive control mechanism and takes advantage of the information in an existing schedule. Finally, the above method is applied to solve the rescheduling problem of a certain type of earth-observing satellite.The computation of the example shows that the approach is feasible and effective in dealing with uncertainties in spacecraft observation scheduling. The approach designed here can be useful in solving the problem that the original schedule is contaminated by disturbances.Li Yuqing Wang Rixin Xu Minqiang 2014Chinese Journal of Aeronautics2014,27,3:19
4Natural^(15)N abundance in soils and plants in relation to N cycling in a rangeland in Inner Mongolia显示文摘Aims Natural 15N abundance provides integrated information about nitrogen(N)input,transformation and output,indirectly reflecting N cycling traits within terrestrial ecosystems.However,relationships between natural 15N abundance and N cycling processes are poorly understood in China.Here,our primary objectives were to(i)examine the effects of grazing at varying levels of intensity on d15N of soils and plants in a semi-arid grassland;(ii)detect the relationships between d15N of soils and four major N cycling processes(i.e.mineralization,nitrification,denitrification and ammonia volatilization);and(iii)determine whether d15N of soils can be used as an indicator of N cycling in this semi-arid grassland.Methods The field experiment was conducted within the long-term(17-year)grazing enclosures in a semi-arid grassland in Inner Mongolia.Five grazing intensities(0.00,1.33,2.67,4.00 and 5.33 sheep ha1)were designed.d15N values of topsoils(0–10 cm),surface soils(0–2 cm)and plants were measured in 2006.Differences in d15N of soils and plants between the five grazing intensities were examined.Rates of four soil N cycling processes were measured periodically during the 2005 and 2006 growing seasons.The d15N values of topsoils were linked to the four N cycling processes to investigate their relationships.Important Findings The d15N values of topsoils(5.20–5.96&)were substantially higher than the d15N values of plants(2.51–2.93&)and surface soils(1.44–2.92&)regardless of grazing intensities.The 15N-depleted N losses during microbial decomposition of organic matter in concert with the downward movement of residual substrate over time are the possible causes of higher d15N values in topsoils than in surface soils.In addition,the d15N values of topsoils were positively correlated with the d15N values of both plants and surface soils.Grazing,especially the high-intensity grazing(5.33 sheep ha1),resulted in a significant decrease in d15N of surface soils.However,no statistically significant variations in d15N of topsoils and plants were found in response to grazing.The d15N values of topsoils exhibited significant dependence on the cumulative rates of NH3 volatilization,net nitrification and denitrification in 2005 but not in 2006.Yuqing Xu Jicheng He Weixin Cheng Xuerong Xing Linghao Li 2010Journal of Plant Ecology2010,3,3:12
5Oral microbiota in human systematic diseases显示文摘Oral bacteria directly affect the disease status of dental caries and periodontal diseases. The dynamic oral microbiota cooperates with the host to reflect the information and status of immunity and metabolism through two-way communication along the oral cavity and the systemic organs. The oral cavity is one of the most important interaction windows between the human body and the environment.The microenvironment at different sites in the oral cavity has different microbial compositions and is regulated by complex signaling,hosts, and external environmental factors. These processes may affect or reflect human health because certain health states seem to be related to the composition of oral bacteria, and the destruction of the microbial community is related to systemic diseases. In this review, we discussed emerging and exciting evidence of complex and important connections between the oral microbes and multiple human systemic diseases, and the possible contribution of the oral microorganisms to systemic diseases. This review aims to enhance the interest to oral microbes on the whole human body, and also improve clinician’s understanding of the role of oral microbes in systemic diseases. Microbial research in dentistry potentially enhances our knowledge of the pathogenic mechanisms of oral diseases,and at the same time, continuous advances in this frontier field may lead to a tangible impact on human health.Xian Peng Lei Cheng Yong You Chengwei Tang Biao Ren Yuqing Li Xin Xu Xuedong Zhou 2022International Journal of Oral Science2022,14,1:9
6Simultaneous state and actuator fault estimation for satellite attitude control systems显示文摘In this paper,a new nonlinear augmented observer is proposed and applied to satellite attitude control systems.The observer can estimate system state and actuator fault simultaneously.It can enhance the performances of rapidly-varying faults estimation.Only original system matrices are adopted in the parameter design.The considered faults can be unbounded,and the proposed augmented observer can estimate a large class of faults.Systems without disturbances and the fault whose finite times derivatives are zero piecewise are initially considered,followed by a discussion of a general situation where the system is subject to disturbances and the finite times derivatives of the faults are not null but bounded.For the considered nonlinear system,convergence conditions of the observer are provided and the stability analysis is performed using Lyapunov direct method.Then a feasible algorithm is explored to compute the observer parameters using linear matrix inequalities(LMIs).Finally,the effectiveness of the proposed approach is illustrated by considering an example of a closed-loop satellite attitude control system.The simulation results show satisfactory performance in estimating states and actuator faults.It also shows that multiple faults can be estimated successfully.Cheng Yao Wang Rixin Xu Minqiang Li Yuqing 2016Chinese Journal of Aeronautics2016,29,3:9
7The Oral Microbiome Bank of China显示文摘The human microbiome project(HMP) promoted further understanding of human oral microbes. However, research on the human oral microbiota has not made as much progress as research on the gut microbiota. Currently, the causal relationship between the oral microbiota and oral diseases remains unclear, and little is known about the link between the oral microbiota and human systemic diseases. To further understand the contribution of the oral microbiota in oral diseases and systemic diseases, a Human Oral Microbiome Database(HOMD) was established in the US. The HOMD includes 619 taxa in 13 phyla, and most of the microorganisms are from American populations. Due to individual differences in the microbiome, the HOMD does not reflect the Chinese oral microbial status. Herein, we established a new oral microbiome database—the Oral Microbiome Bank of China(OMBC,http://gffzz1f92d53390b34408h5nnkb5nq5okx66nb.ffgz.tsg.suse.edu.cn/ombc). Currently, the OMBC includes information on 289 bacterial strains and 720 clinical samples from the Chinese population, along with lab and clinical information. The OMBC is the first curated description of a Chinese-associated microbiome; it provides tools for use in investigating the role of the oral microbiome in health and diseases, and will give the community abundant data and strain information for future oral microbial studies.Xian Peng Xuedong Zhou Xin Xu Yuqing Li Yan Li Jiyao Li Xiaoquan Su Shi Huang Jian Xu Ga Liao 2018International Journal of Oral Science2018,10,2:8
8Genome-wide identification of OSCA gene family and their potential function in the regulation of dehydration and salt stress in Gossypium hirsutum显示文摘Background:Cotton(Gossypium hirsutum) provides the largest natural fiber for the textile manufacturing industries,but its production is on the decline due to the effects of salinity.Soil salt-alkalization leads to damage in cotton growth and a decrease in yields.Hyperosmolality-gated calcium-permeable channels(OSCA) have been found to be involved in the detection of extracellular changes which trigger an increase in cytosolic free calcium concentration.Hyperosmolality-induced calcium ion increases have been widely speculated to be playing a role in osmosensing in plants.However,the molecular nature of the corresponding calcium ion channels remains unclearly.In this research work,we describe the OSCA genes and their putative function in osmosensing in plants by carrying out genomewide identification,characterization and functional analysis of the significantly up-regulated OSCA gene,GhOSCA1.1 through reverse genetics.Result:A total of 35,21 and 22 OSCA genes were identified in G.hirsutum,G.arboreum,and G.raimondii genomes,respectively,and were classified into four different clades according to their gene structure and phylogenetic relationship.Gene and protein structure analysis indicated that 35 GhOSCA genes contained a conserved RSN17 TM(PF02714) domain.Moreover,the cis-regulatory element analysis indicated that the OSCA genes were involved in response to abiotic stress.Furthermore,the knockdown of one of the highly up-regulated genes,GhOSCA1.1 showed that the virus-induced gene silenced(VIGS) plants were highly sensitive to dehydration and salinity stresses compared with the none VIGS plants as evident with higher concentration levels of oxidant enzymes compared with the antioxidant enzymes on the leaves of the stressed plants.Conclusion:This study provides the first systematic analysis of the OSCA gene family and will be important for understanding the putative functions of the proteins encoded by the OSCA genes in cotton.These results provide a new insight of defense responses in general and lay the foundation for further investigation of the molecular role played by the OSCA genes,thereby providing suitable approaches to improve crop performance under salinity and drought stress conditions.YANG Xiu XU Yanchao YANG Fangfang MAGWANGA Richard Odongo CAI Xiaoyan WANG Xingxing WANG Yuhong HOU Yuqing WANG Kunbo LIU Fang ZHOU Zhongli 2019Journal of Cotton Research2019,2,2:7
9Reconstruction of a hybrid nucleoside antibiotic gene cluster based on scarless modification of large DNA fragments显示文摘Genetic modification of large DNA fragments(gene clusters) is of great importance in synthetic biology and combinatorial biosynthesis as it facilitates rational design and modification of natural products to increase their value and productivity.In this study,we developed a method for scarless and precise modification of large gene clusters by using RecET/RED-mediated polymerase chain reaction(PCR) targeting combined with Gibson assembly.In this strategy,the biosynthetic genes for peptidyl moieties(HPHT) in the nikkomycin biosynthetic gene cluster were replaced with those for carbamoylpolyoxamic acid(CPOAA)from the polyoxin biosynthetic gene cluster to generate a^40 kb hybrid gene cluster in Escherichia coli with a reusable targeting cassette.The reconstructed cluster was introduced into Streptomyces lividans TK23 for heterologous expression and the expected hybrid antibiotic,polynik A,was obtained and verified.This study provides an efficient strategy for gene cluster reconstruction and modification that could be applied in synthetic biology and combinatory biosynthesis to synthesize novel bioactive metabolites or to improve antibiotic production.Jiming Zhuo Binbin Ma Jingjing Xu Weihong Hu Jihui Zhang Huarong Tan Yuqing Tian 2017Science China(Life Sciences)2017,60,9:6
10A draft sequence of the rice (Oryza sativa ssp. indica) genome显示文摘The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development, and evolution, as well as information on many beneficial phenotypes of economic significance. Using a 'whole genome shotgun' approach, we have pro-duced a draft rice genome sequence of Oryza sativa ssp. in-dica, the major crop rice subspecies in China and many other regions of Asia. The draft genome sequence is constructed from over 4.3 million successful sequencing traces with an accumulative total length of 2214.9 Mb. The initial assembly of the non-redundant sequences reached 409.76 Mb in length, based on 3.30 million successful sequencing traces with a total length of 1797.4 Mb from an indica variant cultivar 93-11, giving an estimated coverage of 95.29% of the rice genome with an average base accuracy of higher than 99%. The coverage of the draft sequence, the randomness of the sequence distribution, and the consistency of BIG-ASSEM-BLER, a custom-designed software packageYU Jun, HU Songnian, WANG Jun,LI Songgang WONG Ka-Shu Gane, LIU Bin,DENG Yajun, DAI Li, ZHOU Yan,ZHANG Xiuqing, CAO Mengliang, LIU Jing,SUN Jiandong , TANG Jiabin, CHEN Yanjiong,HUANG Xiaobing, LIN Wei, YE Chen, TONG Wei,CONG Lijuan, GENG Jianing, HAN Yujun, LI Lin,LI Wei, HU Guangqiang, HUANG Xiangang,LI Wenjie, LI Jian, LIU Zhanwei, LI Long,LIU Jianping, Ql Qiuhui, LIU Jinsong, LI Li,WANG Xuegang, LU Hong, WU Tingling,ZHU Miao, Nl Peixiang, HAN Hua, DONG Wei,REN Xiaoyu, FENG Xiaoli, GUI Peng,LI Xianran, WANG Hao, XU Xin, ZHAI Wenxue,XU Zhao, ZHANG Jinsong, HE Sijie,ZHANG Jianguo, XU Jichen, ZHANG Kunlin,ZHENG Xianwu, DONG Jianhai, ZENG Wanyong,TAO Lin, CHEN Xuewei, HE Jun, LIU Daofeng,TIAN Wei, TIAN Chaoguang, XIA Hongai,LI Gang, GAO Hui, LI Ping, CHEN Wei ,WANG Xudong, ZHANG Yong, HU Jianfei,WANG Jing, LIU Song, YANG Jian,ZHANG Guangyu, XIONG Yuqing, LI Zhijie,MAO Long, ZHOU Chengshu, ZHU Zhen,CHEN Runsheng, HAO Bailin,ZHENG Weimou, CHEN Shouyi, QUO Wei,LI Guojie, LIU Siqi, HUANG Guyang,TAO Ming, WANG Jian, ZHU Lihuang,YUAN Longping& YANG HuanmingBeijing Genomics Institute/Center of Genomics & Bioinformatics, Chinese Academy of Sciences, Beijing 101300, China Hangzhou Genomics Institute/Institute of Bioinformatics of Zhejiang University/Key Laboratory of Bioinformatics of Zhejiang Province, Hangzhou 310007, China Institute of Genetics, Chinese Academy of Sciences, Beijing 100101, China National Hybrid Rice R & D Center, Changsha 410125, China Laboratory of Bioinformatics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China College of Life Sciences, Peking University, Beijing 100871, China Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 1Q0080, China Digital China Ltd., Beijing 100080, China Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100080, China Medical College, Xi’an Jiaotong University, Xi’an 710061, ChinaThese authors contributed equally to this work.Corresponding author.Corresponden 2001Chinese Science Bulletin2001,46,23:6
11Aerosol light absorption in a coastal city in Southeast China:Temporal variations and implications for brown carbon显示文摘Light-absorbing carbonaceous aerosols including black carbon(BC) and brown carbon(BrC)play significant roles in atmospheric radiative properties. One-year measurements of aerosol light absorption at multi-wavelength were continuously conducted in Xiamen,southeast of China in 2014 to determine the light absorption properties including absorption coefficients(σabs) and absorption ?ngstr?m exponent(AAE) in the coastal city.Light absorptions of BC and BrC with their contributions to total light absorption were further quantified. Mean σabsat 370 nm and 880 nm were 56.6 ± 34.3 and 16.5 ± 11.2 Mm-1,respectively. σabspresented a double-peaks diurnal pattern with the maximum in the morning and the minimum in the afternoon. σabswas low in warm seasons and high in cold seasons. AAE ranged from 0.26 to 2.58 with the annual mean of 1.46, implying that both fossil fuel combustion and biomass burning influenced aerosol optical properties. σabsof BrC at 370 nm was 24.0 ± 5.7 Mm-1, contributing 42% to the total absorption. The highest AAE(1.52 ± 0.02) and largest BrC contributions(47% ± 4%) in winter suggested the significant influence of biomass burning on aerosol light absorption. Long-distance air masses passing through North China Plain and the Yangtze River Delta led to high AAE and BrC contributions. High AAE value of 1.46 in July indicated that long-range transport of the air pollutants from intense biomass burning in Southeast Asia would affect aerosol light absorption in Southeast China. The study will improve the understanding of light absorption properties of aerosols and the optical impacts of BrC in China.Yuqing Qiu Xin Wu Yanru Zhang Lingling Xu Youwei Hong Jinsheng Chen Xiaoqiu Chen Junjun Deng 2019Journal of Environmental Sciences2019,31,6:5
12Fault detection of flywheel system based on clustering and principal component analysis显示文摘Considering the nonlinear, multifunctional properties of double-flywheel with closedloop control, a two-step method including clustering and principal component analysis is proposed to detect the two faults in the multifunctional flywheels. At the first step of the proposed algorithm,clustering is taken as feature recognition to check the instructions of ‘‘integrated power and attitude control' system, such as attitude control, energy storage or energy discharge. These commands will ask the flywheel system to work in different operation modes. Therefore, the relationship of parameters in different operations can define the cluster structure of training data. Ordering points to identify the clustering structure(OPTICS) can automatically identify these clusters by the reachability-plot. K-means algorithm can divide the training data into the corresponding operations according to the reachability-plot. Finally, the last step of proposed model is used to define the relationship of parameters in each operation through the principal component analysis(PCA) method.Compared with the PCA model, the proposed approach is capable of identifying the new clusters and learning the new behavior of incoming data. The simulation results show that it can effectively detect the faults in the multifunctional flywheels system.Wang Rixin Gong Xuebing Xu Minqiang Li Yuqing 2015Chinese Journal of Aeronautics2015,28,6:5
13Expert consensus on early childhood caries management显示文摘Early childhood caries(ECC)is a significant chronic disease of childhood and a rising public health burden worldwide.ECC may cause a higher risk of new caries lesions in both primary and permanent dentition,affecting lifelong oral health.The occurrence of ECC has been closely related to the core microbiome change in the oral cavity,which may be influenced by diet habits,oral health management,fluoride use,and dental manipulations.So,it is essential to improve parental oral health and awareness of health care,to establish a dental home at the early stage of childhood,and make an individualized caries management plan.Dental interventions according to the minimally invasive concept should be carried out to treat dental caries.This expert consensus mainly discusses the etiology of ECC,caries-risk assessment of children,prevention and treatment plan of ECC,aiming to achieve lifelong oral health.Jing Zou Qin Du Lihong Ge Jun Wang Xiaojing Wang Yuqing Li Guangtai Song Wei Zhao Xu Chen Beizhan Jiang Yufeng Mei Yang Huang Shuli Deng Hongmei Zhang Yanhong Li Xuedong Zhou 2022International Journal of Oral Science2022,14,3:5
14LIN28 coordinately promotes nucleolar/ribosomal functions and represses the 2C-like transcriptional program in pluripotent stem cells显示文摘LIN28 is an RNA binding protein with important roles in early embryo development,stem cell differentiation/re-programming,tumorigenesis and metabolism.Previous studies have focused mainly on its role in the cytosol where it interacts with Let-7 microRNA precursors or mRNAs,and few have addressed LIN28's role within the nucleus.Here,we show that LIN28 displays dynamic temporal and spatial expression during murine embryo development.Maternal LIN28 expression drops upon exit from the 2-cell stage,and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blas-tocyst stage development,to become dominantly expressed in the cytosol after implantation.In cultured pluripotent stem cells(PSCs),loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus genes.Mechanistically,LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity,and its loss leads to nucleolar phase separation defects,ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factor Dux.LIN28 also resides in a complex containing the nucleolar factor Nucleolin(NCL)and the transcrip-tional repressor TRIM28,and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on the Dux and rDNA loci,and thus de-repressed Dux and reduced rRNA expression.Lin28 knockout cells with nucleolar stress are more likely to assume a slowly cycling,translationally inert and anabolically inactive state,which is a part of previously unappreciated 2C-like transcriptional program.These findings elucidate novel roles for nucleolar LIN28 in PSCs,and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development.Zhen Sun Hua Yu Jing Zhao Tianyu Tan Hongru Pan Yuqing Zhu Lang Chen Cheng Zhang Li Zhang Anhua Lei Yuyan Xu Xianju Bi Xin Huang Bo Gao Longfei Wang Cristina Correia Ming Chen Qiming Sun Yu Feng Li Shen Hao Wu Jianlong Wang Xiaohua Shen George Q.Daley Hu Li Jin Zhang 2022Protein & Cell2022,13,7:4
15Is Process as Important as Outcome? Empirical Evidence from the Chinese Context显示文摘尽管在薪水水平和薪水满足之间的关系在薪水满足的文学作为最柔韧的关系之一被验证了,学者们还没关于它的内在的机制达成了一个协议。调查在绝对薪水水平和薪水之间的连接的现在的纸目的由根据公平作为调停人介绍分发、程序的公平感觉铺平满足启发式的观点。从组织的各种各样的类型的 298 个雇员的一件样品完成了调查,并且一系列模型与相比如果假设理论模型适合我们的数据,评估。我们也构造了改正偏爱自举测试假设调停效果的信心间隔。建议理论模型被支持,并且未来研究方向被讨论。Lel Wang ShiYong Xu Wei Huang Yuqing Zhang 2014Frontiers of Business Research in China2014,8,4:4
16Genetic architecture and key genes controlling the diversity of oil composition in rice grains显示文摘Rice grain oil is a valuable nutrient source.However,the genetic basis of oil biosynthesis in rice grains remains unclear.In this study,we performed a genome-wide association study on oil composition and oil concentration in a diverse panel of 533 cultivated rice accessions.High variation for 11 oil-related traits was observed,and the oil composition of rice grains showed differentiation among the subpopulations.We identified 46 loci that are significantly associated with grain oil concentration or composition,16 of which were detected in three recombinant inbred line populations.Twenty-six candidate genes encoding enzymes involved in oil metabolism were identified from these 46 loci,four of which(PAL6,LIN6,MYR2,and ARA6)were found to contribute to natural variation in oil composition and to show differentiation among the subpopulations.Interestingly,population genetic analyses revealed that specific haplotypes of PAL6 and LIN6 have been selected in japonica rice.Based on these results,we propose a possible oil biosynthetic pathway in rice grains.Collectively,our results provide new insights into the genetic basis of oil biosynthesis in rice grains and can facilitate marker-based breeding of rice varieties with enhanced oil and grain quality.Hao Zhou Duo Xia Pingbo Li Yiting Ao Xiaodong Xu Shanshan Wan Yanhua Li Bian Wu Huan Shi Kaiyue Wang Guanjun Gao Qinglu Zhang Gongwei Wang Jinghua Xiao Xianghua Li Sibin Yu Xingming Lian Yuqing He 2021Molecular Plant2021,14,3:4
17Morphology and magnetic properties of Sm_(2)Co_(7)/α-Fe nanocomposite magnets produced by high energy ball milling and spark plasma sintering显示文摘In this article,the Sm_(2)Co_(7)/α-Fe nanocomposite magnets were prepared by high energy ball milling and spark plasma sintering method.The effect of soft phase content on the magnetic properties was studied.Up to 30 wt% α-Fe was added into Sm_(2)Co_(7) matrix without the decrease of remanence.Optimal energy product(BH)max of 9.2 MGOe was obtained with 20 wt% α-Fe.TEM observation shows that the grain size of α-Fe is 20-50 nm which ensures a good coupling effect between soft and hard phase.One more thing needs to be mentioned is that there exists inter-diffusion between Sm-Co phase and α-Fe phase.Moreover,our results can also illustrate that the Sm_(2)Co_(7)/α-Fe nanocomposite magnets are able to acquire better magnetic properties than the SmCo_(5)/α-Fe magnets prepared by the same process due to the large domain width of Sm_(2)Co_(7) phase.Yitong Zhuge Yuqing Li Xiaochang Xu Dongtao Zhang Hongguo Zhang Weiqiang Liu Ming Yue 2021Journal of Rare Earths2021,39,3:3
18Ambulatory blood pressure profile and stroke recurrence显示文摘Objectives To establish a new ambulatory blood pressure(ABP)parameter(24-hour ABP profile)and evaluated its performance on stroke outcome in ischaemic stroke(IS)or transient ischaemic attack(TIA)patients.Methods The prospective cohort consisted of 1996 IS/TIA patients enrolled for ABP monitoring and a 3-month follow-up for stroke recurrence as outcome.Profile groups of systolic blood pressure(SBP)were identified via an advanced functional clustering method,and the associations of the profile groups and conventional ABP parameters with stroke recurrence were examined in a Cox proportional hazards model.Results Three discrete profile groups(n=604,781 and 611 in profiles 1,2 and 3,respectively)in 24-hour ambulatory SBP were identified.Profile 1 resembled most to the normal diurnal blood pressure pattern;profile 2 also dropped at night,but climbed earlier and with higher morning surge;while profile 3 had sustained higher nocturnal SBP without significant nocturnal SBP decline.The incidence of stroke recurrence was 2.9%,3.9%and 5.5%in profiles 1,2 and 3,respectively.After adjustment for covariates,profile 3 was significantly associated with higher risk of stroke recurrence with profile 1 as reference(HR 1.76,95%CI:1.00 to 3.09),while no significant difference was observed between profiles 2 and 1(HR 1.22,95%CI:0.66 to 2.25).None of conventional ABP parameters showed significant associations with the outcome.Conclusions Ambulatory 24-hour SBP profile is associated with short-term stroke recurrence.Profiles of ABP may help improve identification of stroke recurrence by capturing the additive effects of individual ABP parameters.Jie Xu Fei Jiang Anxin Wang Hui Zhi Yuan Gao Junping Tian Jinglin Mo Zimo Chen An-Ding Xu Benyan Luo Bo Hu Yuqing Zhang Xingquan Zhao Yilong Wang Hao Li Haipeng Shen Yongjun Wang 2021Stroke & Vascular Neurology2021,6,3:3
19MicroRNA-145, a Novel Smooth Muscle Cell Phenotypic Marker and Modulator, Controls Vascular Neointimal Lesion Formation显示文摘Yunhui Cheng Xiaojun Liu Jian Yang Ying Lin Da-Zhong Xu Qi Lu Edwin A. Deitch Yuqing Huo Ellise S. Delphin Chunxiang Zhang 2009Circulation Research2009,,2:2
20Effect of heterogeneous microstructure on magnetization reversal mechanism of hot-deformed Nd-Fe-B magnets显示文摘The hot-deformed(HD) Nd-Fe-B magnets show heterogeneous microstructure composed of coarse and fine grain regions. It is significant to fully understand the influence of this complex microstructure on the magnetization reversal process which can give the guidance for the enhancement of the magnetic properties. In this paper, the heterogeneous microstructure of the(HD) Nd-Fe-B magnets were characterized from the morphology, size, macro-texture and micro-structure. In addition, the magnetization reversal process of the HD Nd-Fe-B magnets was systematically analyzed by magnetic measurement, insitu domain evolution observation and micromagnetic simulation. The results indicate that the HD NdFe-B magnets mainly consist of fine grain regions(FGRs) and coarse grain regions(CGRs). The FGRs show plate-like grains with fine grain size and strong c-axis texture, while the CGRs show equiaxial grains with large grain size and weak c-axis texture. In particular, it is worth noting that the texture in homogeneity exists not only between FGRs and CGRs, but also inside both the FGRs and CGRs. The dominant coercivity mechanism of the HD Nd-Fe-B magnets is domain wall pinning. Also, the experimental analysis shows that the reverse domain is formed and expanded in the CGRs at low reverse applied field, while the reverse domain occurs in the FGRs at higher reverse applied field. The micromagnetic simulation results also confirm the above magnetization reversal process. In addition, micromagnetic simulation results also show that the orientation of the grains also affects the pinning strength, besides the grain size.Yuqing Li Xiaochang Xu Ming Yue Dan Wu Weiqiang Liu Dongtao Zhang 2019Journal of Rare Earths2019,37,10:2
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