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Development of a real-time RT-PCR method for the detection of newly emerged highly pathogenic H7N9 influenza viruses

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Journal of Integrative Agriculture 2017年第9期16卷 2055-2061页

作者： WANG Xiu-rong GU Lin-lin SHI Jian-zhong XU Hai-feng ZHANG Ying ZENG Xian-ying DENG guo-hua LI Cheng-jun CHEN Hua-lan State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069P.R.China

In 2013, a human influenza outbreak caused by a novel H7N9 virus occurred in China. Recently, the H7N9 virus acquired multiple basic amino acids at its hemagglutinin（HA） cleavage site, leading to the emergence of a highly pathogenic virus. The development of an effective diagnostic method is imperative for the prevention and control of highly pathogenic H7N9 influenza. Here, we designed and synthesized three pairs of primers based on the nucleotide sequence at the HA cleavage site of the newly emerged highly pathogenic H7N9 influenza virus. One of the primer pairs and the corresponding probe displayed a high level of amplification efficiency on which a real-time RT-PCR method was established. Amplification using this method resulted in a fluorescent signal for only the highly pathogenic H7N9 virus, and not for any of the H1–H15 subtype reference strains, thus demonstrating high specificity. The method detected as low as 39.1 copies of HA-positive plasmid and exhibited similar sensitivity to the virus isolation method using embryonated chicken eggs. Importantly, the real-time RT-PCR method exhibited 100% consistency with the virus isolation method in the diagnosis of field samples. Collectively, our data demonstrate that this real-time RT-PCR assay is a rapid, sensitive and specific method, and the application will greatly aid the surveillance, prevention, and control of highly pathogenic H7N9 influenza viruses.

关键词： H7N9 highly pathogenic influenza virus real-time RT-PCR

2维线元不确定性ε_σ模型误差带几何特征的代数研究

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测绘学报 2007年第4期36卷 463-467页

作者：朱长青张国芹史文中南京大师范大学虚拟把环境教育部重要实验室信息工程大学理学院河南郑州450001 香港理工大学土地测量与地理资讯学系

对地理信息系统(GIS)中2维线元不确定性εσ模型的误差带的几何特征进行研究。运用函数单调性和极值理论,从理论上证明εσ模型的误差带的几何特征;得到线元误差带不仅具有"两端大、中间小",而且也可能具有"一端大、一端小"的几何形状;... 详细信息

对地理信息系统(GIS)中2维线元不确定性εσ模型的误差带的几何特征进行研究。运用函数单调性和极值理论,从理论上证明εσ模型的误差带的几何特征;得到线元误差带不仅具有"两端大、中间小",而且也可能具有"一端大、一端小"的几何形状;给出了误差带的最小带宽及其位置;论证了误差带的最小误差带宽的位置靠近中误差较小的一端。本研究完善了2维线元不确定性εσ模型,使其更具有严密性,同时为GIS空间数据不确定性的研究提供了新的方法。

关键词： GIS 不确定性 εσ模型误差带几何特征

Ab initio study of dynamical properties of U-Nb alloy melt

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Chinese Physics B 2021年第12期30卷 515-522页

作者： Yong-Peng Shi Ming-Feng Liu Yun Chen wen-Lin Mo Dian-zhong Li Tao Fa Bin Bai Xiao-Lin Wang Xing-Qiu Chen Shenyang National Laboratory for Materials science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaShenyang 110016China Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China

The U-Nb alloy,as a kind of nuclear material with good corrosion resistance and mechanical properties,plays an important role in the nuclear ***,the experimental measurements and theoretical calculations of many parameters which are essential in describing the dynamical properties of this alloy melt,including density,diffusivity,and viscosity,have not been carried out *** lack of data on the dynamical properties of nuclear materials seriously hinders the high-performance nuclear materials from being developed and *** this work,the dynamical properties of the U-Nb alloy melt are systematically studied by means of ab initio molecular dynamics simulations and their corresponding mathematical models are established,thereby being able to rapidly calculate the densities,diffusion coefficients,viscosities,and their activation energies in the whole U-Nb liquid *** work provides a new idea for investigating the dynamical properties of binary alloy melts,thereby promoting the development of melt research.

关键词： U-Nb alloy melt dynamical properties ab initio study

Comparisons of Supine Roll Test and Alternative Positional Tests in HC-BPPV Lateralization

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Current Medical science 2022年第3期42卷 613-619页

作者： Geeta KOJU Dan BING Liang-qiang ZHOU zhong-yao MAO Yan-ling TAO Qing-guo CHEN Jin CHEN Yun LIU Ting TONG Han-qi CHU Department of Otolaryngology-Head and Neck Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective The purpose of the study was to evaluate the efficiency of the supine roll test(SRT)and alternative positional tests(APTs)including the bow and lean test(BLT),pseudo-spontaneous nystagmus(PSN),and lying down nystagmus(LDN)to identify the affected side in horizontal canal benign paroxysmal positional vertigo(HC-BPPV).Methods In our prospective study,we performed a testing profile(PSN,BLT,LDN,SRT)on 59 HC-BPPV patients using *** compared the accuracy and sensitivity of these tests in HC-BPPV *** from 30 healthy patients were collected as the control *** When performing positional tests,the elicited nystagmus coinciding with Ewald’s second law was defined as a“positive response”.In 44 patients with geotropic nystagmus,the rates of positive response in LDN,PSN,and BLT were 22/44(50%),19/44(43%),and 18/44(41%),respectively,while in 15 patients with apogeotropic nystagmus,the positive response rates of these three tests were 10/15(66.7%),9/15(60%),and 4/15(27.00%),*** sensitivity of LDN(54.38%)was higher than that of PSN(47.37%)and BLT(38.60%)but lower than that of SRT(89.47%).Notably,the accuracy rate of PSN(71.8%)was higher than that of the other *** 6 patients with symmetrical nysgtamus during the roll test,5 patients showed a positive response in both LDN and BLT(83.34%),whereas 4 patients showed a positive response in PSN(66.67%).Conclusion All positional tests are helpful for determining the affected side of HC-BPPV,but SRT carries the highest accuracy of lateralization followed by PSN.

关键词： horizontal canal benign paroxysmal positional vertigo pseudo spontaneous nystagmus bow and lean test lying down nystagmus supine roll test

Fecal microbial biomarkers combined with multi-target stool DNA test improve diagnostic accuracy for colorectal cancer

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World Journal of Gastrointestinal Oncology 2023年第8期15卷 1424-1435页

作者： Jin-Qing Fan Wang-Fang Zhao Qi-wen Lu Fu-Rong Zha Le-Bin Lv guo-Liang Ye Han-Lu Gao Department of Traditional Chinese Medicine The First Affiliated Hospital of Ningbo UniversityNingbo 315000Zhejiang ProvinceChina Department of Gastroenterology The First Affiliated Hospital of Ningbo UniversityNingbo 315000Zhejiang ProvinceChina Department of Bioinformation Analysis Shanghai BIOZERON Biotechnology Co.Shanghai 201800China Department of Preventive Medicine The First Affiliated Hospital of Ningbo UniversityNingbo 315000Zhejiang ProvinceChina

BACKGROUND Colorectal cancer(CRC)is a major global health *** current diagnostic tests have shortcomings of being invasive and low *** To explore the combination of intestinal microbiome composition and multi-target stool DNA(MT-sDNA)test in the diagnosis of *** We assessed the performance of the MT-sDNA test based on a hospital clinical *** intestinal microbiota was tested using 16S rRNA gene *** case-control study enrolled 54 CRC patients and 51 healthy *** identified biomarkers of bacterial structure,analyzed the relationship between different tumor markers and the relative abundance of related flora components,and distinguished CRC patients from healthy subjects by the linear discriminant analysis effect size,redundancy analysis,and random forest *** MT-sDNA was associated with ***-sDNA and carcinoembryonic antigen(CEA)were positively correlated with the existence of Parabacteroides,and alpha-fetoprotein(AFP)was positively associated with Faecalibacterium and *** the random forest model,the existence of Streptococcus,Escherichia,Chitinophaga,Parasutterella,Lachnospira,and Romboutsia can distinguish CRC from health *** diagnostic accuracy of MT-sDNA combined with the six genera and CEA in the diagnosis of CRC was 97.1%,with a sensitivity and specificity of 98.1%and 92.3%,*** There is a positive correlation of MT-sDNA,CEA,and AFP with intestinal *** biomarkers including six genera of gut microbiota,MT-sDNA,and CEA showed a prominent sensitivity and specificity for CRC prediction,which could be used as a non-invasive method for improving the diagnostic accuracy for this malignancy.

关键词： Gut microbiome Colorectal cancer Diagnostic model Multi-target stool DNA test Tumor biomarker

Radical SAM-Dependent Adenosylation Involved in Bacteriohopane-polyol Biosynthesis

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Chinese Journal of Chemistry 2020年第1期38卷 39-42页

作者： Yuting zhong Xinjian Ji Qi Zhang Department of Chemistry FudanUniversityShanghai 200433China

Summaryof main observation and conclusion Bacteriohopanepolyols are a group of triterpenoids that play important rolesin regulating bacterial cell membrane *** an intermediate in bacteriohopanepolyol biosynthesis,adenosylhopane production is related to a putative Fe-S protein HpnH,but the exact role of this enzyme remains *** we report characterization of HpnH as a novel radical S-adenosylmethionine(SAM)superfamily *** contrast to almost all the members in the superfamily,HpnH does not initiate the reaction by a hydrogen atom abstraction ***,it catalyzes the adenosylation of hopene via a radical addition reaction to produce adenosylhopane,representing the second example of radical SAM-dependent adenosylation involved in natural product biosynthesis.

关键词： function. process. polyol

煤层气在多孔介质填充管线反应器中的水合实验研究

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煤炭学报 2016年第4期41卷 871-875页

作者：李文涛郭博婷赵建忠太原理工大学采矿工艺研究所山西太原030024 大同煤矿集团有限责任公司晋华宫矿山西大同037016 太原理工大学矿业工程学院山西太原030024

针对目前传统方式(低温液化、变压吸附、膜分离等)对低浓度煤层气增浓工业化应用的不适用性问题,提出通过合成水合物的方式实现低浓度煤层气中CH4的富集。但该技术的实现需要解决煤层气水合物合成过程中合成速率慢、储气密度低两个问题... 详细信息

针对目前传统方式(低温液化、变压吸附、膜分离等)对低浓度煤层气增浓工业化应用的不适用性问题,提出通过合成水合物的方式实现低浓度煤层气中CH4的富集。但该技术的实现需要解决煤层气水合物合成过程中合成速率慢、储气密度低两个问题。借鉴日本对管线式反应器的试验结果与目前理论与实验研究所得出的THF与SDS分别对水合物合成相平衡条件、储气密度、合成速率的最佳促进浓度配比和多孔介质的加入对水合物合成促进作用的研究成果,以5×10-10m沸石分子筛填充管线反应器作为水合界面,研究了摩尔分数17%THF+质量分数300×10-6SDS理论最佳促进体系下的水合物合成速率变化与工业化实现指标。实验结果表明:随着压力的升高,整体管线反应速率加快,合成速率峰值沿反应管线前移;水合驱动力的升高可有效提高水合物储气效率,且过压驱动力对水合储气的影响强于过冷驱动力;284 K/1.5 MPa条件下利用一次反应后多孔介质进行二次合成,达到相同储气量时,反应时间仅为一次合成的10%;随着水合时间的延长,284 K/1.8 MPa条件下水合单位耗气达到了67.25 m L/m L,配合二次合成对水合时间的缩短效应,可大大提高水合物合成的储气速率与储气密度。

关键词：煤层气水合物多孔介质储气管线反应器

Functional analysis of a novel C-glycosyltransferase in the orchid Dendrobium catenatum

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Horticulture Research 2020年第1期7卷 1426-1443页

作者： Zhiyao Ren Xiaoyu Ji Zhenbin Jiao Yingyi Luo guo-Qiang Zhang Shengchang Tao Zhouxi Lei Jing Zhang Yuchen Wang zhong-Jian Liu Gang Wei school of Pharmaceutical sciences Guangzhou University of Chinese MedicineGuangzhou 510006China Shantou University Medical College Shantou 515041China State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of sciences Beijing 100049China Shenzhen Key Laboratory for Orchid Conservation and Utilization The National Orchid Conservation Center of China and The Orchid Conservation and Research Center of ShenzhenShenzhen 518114China Department of Pharmacy Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhou 510120 GuangdongChina Shaoguan Institute of Danxia Dendrobium Officinale Shaoguan 512005China Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization College of Landscape ArchitectureFujian Agriculture and Forestry UniversityFuzhou 350002China Henry Fok College of Biology and Agriculture Shaoguan UniversityShaoguan 512005China

Flavonoids,which are a diverse class of phytonutrients,are used by organisms to respond to nearly all abiotic stresses and are beneficial for human ***,used during the last step of flavonoid biosynthesis,is important in flavonoid ***,little is known about glycosyltransferase in the orchid Dendrobium catenatum(***).In this study,we isolated a novel C-glycosyltransferase(designated DcaCGT)from the orchid *** by identifying and analyzing 82 putative genes in the GT1 *** could specifically catalyze not only di-C-glycosylation but also *** from the normal function of catalyzing 2-hydroxynaringenin and phloretin to the respective di-C-glycosides,DcaCGT also catalyzes apigenin to *** metabolic profiling of the substrates(2-hydroxynaringenin,phloretin,and apigenin)and products(vitexin,isovitexin,vicenin-2,nothofagin,3’,5’-di-C-glucosylphloretin,and cosmosiin)in different tissues showed that vicenin-2 was the most abundant product of this novel *** was detected in flowers and flower *** also established that DcaCGT functions expanded throughout the evolution of *** OGT activity may help *** resist drought *** study illustrates the function,origin,and differentiation of DcaCGT and provides insights into glycosylation and molecular propagation processes,which can be used to improve the production of flavonoids by the cultivated medicinal plant ***.

关键词： flowers expanded drought

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金属带式无级变速器

东北大学学报（自然科学版） 2000年第5期21卷 505-508页

作者：程乃士刘温李来平郭大中东北大学机械工程与自动化学院辽宁沈阳110006

金属带式无级变速器 (MetalV beltCVT)是一种新型的机械摩擦式无级变速器 ,具有承载能力强、效率高、平稳性好、环保节能等优良的传动特性 ,它特别适用于需要传递中大功率而又需无级调速的场合·主要以其在轿车中的应用介绍了它的发展... 详细信息

金属带式无级变速器 (MetalV beltCVT)是一种新型的机械摩擦式无级变速器 ,具有承载能力强、效率高、平稳性好、环保节能等优良的传动特性 ,它特别适用于需要传递中大功率而又需无级调速的场合·主要以其在轿车中的应用介绍了它的发展过程和现状 ,基本结构 ,传动原理 ,性能特点和发展趋势·

关键词：汽车无级变速器金属带摩擦传动机械摩擦式