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Beta-and Novel Delta-Coronaviruses Are Identified from Wild Animals in the Qinghai-Tibetan Plateau, China

Virologica Sinica 2021年第3期36卷 402-411页

作者： Wentao Zhu Jing Yang Shan Lu ruiting lan Dong Jin Xue-lian Luo Ji Pu Shusheng Wu Jianguo Xu State Key Laboratory of Infectious Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Shanghai Public Health Clinical Center Fudan UniversityShanghai 201508China Research Units of Discovery of Unknown Bacteria and Function Chinese Academy of Medical SciencesBeijing 100730China School of Biotechnology and Biomolecular Sciences University of New South WalesSydneyNSW 2052Australia Yushu Prefecture Center for Disease Control and Prevention Yushu 815000China Department of Laboratorial Science and Technology&Vaccine Research Center School of Public HealthPeking UniversityBeijing 100191China

Outbreaks of severe virus infections with the potential to cause global pandemics are increasingly concerning. One type of those commonly emerging and re-emerging pathogens are coronaviruses(SARS-Co V, MERS-Co V and SARS-Co V-2).Wild animals are hosts of different coronaviruses with the potential risk of cross-species transmission. However, little is known about the reservoir and host of coronaviruses in wild animals in Qinghai Province, where has the greatest biodiversity among the world's high-altitude regions. Here, from the next-generation sequencing data, we obtained a known beta-coronavirus(beta-Co V) genome and a novel delta-coronavirus(delta-Co V) genome from faecal samples of 29 marmots, 50 rats and 25 birds in Yushu Tibetan Autonomous Prefecture, Qinghai Province, China in July 2019. According to the phylogenetic analysis, the beta-Co V shared high nucleotide identity with Coronavirus HKU24. Although the novel delta-Co V(Mt Co V) was closely related to Sparrow deltacoronavirus ISU42824, the protein spike of the novel delta-Co V showed highest amino acid identity to Sparrow coronavirus HKU17(73.1%). Interestingly, our results identified a novel host(Montifringilla taczanowskii) for the novel delta-Co V and the potential cross-species transmission. The most recent common ancestor(t MRCA) of Mt Co Vs along with other closest members of the species of Coronavirus HKU15 was estimated to be 289 years ago. Thus, this study increases our understanding of the genetic diversity of beta-Co Vs and deltaCo Vs, and also provides a new perspective of the coronavirus hosts.

关键词： Coronavirus Qinghai-Tibetan plateau Rat Montifringilla taczanowskii Marmot

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Multiscale Analysis on Two-dimensional Nanoscale Adhesive Contacts

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 446-455页

作者： TONG ruiting LIU Geng LIU lan Key Laboratory of Contemporary Design and Integrated Manufacturing Technology of Ministry of Education Northwestern Polytechnical UniversityXi'an 710072China

Nanoscale adhesive contacts play a key role in micro/nano-electro-mechanical systems as the dimension of the components come to *** studies on nanoscale adhesive contacts are limited by some uncertain factors and the cost of experiments is too ***,nanoscale textured surfaces are difficult to process and nanoscale adhesive contacts of textured surfaces are still lack of *** using multiscale method,which couples molecular dynamics simulation and finite element method,two-dimensional nanoscale adhesive contacts between a rigid cylindrical tip and an elastic substrate are *** the contacts between the rigid cylindrical tip and smooth surface,Von Mises stress distributions,the maximum Von Mises stresses,and contact forces are compared for different radii to show the size effects and adhesive *** phenomena of hysteresis are observed and more obvious as the radii of the tip *** influences of indentation depth and indentation speed are also *** two series of textured surfaces are employed,and the influences of the texture asperity shape,asperity height,and asperity spacing on contact forces are *** contact forces comparisons show that textured surfaces can reduce contact forces effectively in the range of the two *** forces of textured surfaces increase as the asperity heights increase,and textured surfaces with smaller asperity spacing will get higher contact *** forces may be controlled through textured surfaces in the *** obtained results will help to improve contact condition and provide theory basis for texture design.

关键词： nanoscale adhesive contact multiscale method surface texture

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Adaptive Multiscale Method for Two-dimensional Nanoscale Adhesive Contacts

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Chinese Journal of Mechanical Engineering 2013年第3期26卷 606-612页

作者： TONG ruiting LIU Geng LIU lan WU Liyan School of Mechanical Engineering Northwestern Polytechnical University

There are two separate traditional approaches to model contact problems: continuum and atomistic theory. Continuum theory is successfully used in many domains, but when the scale of the model comes to nanometer, continuum approximation meets challenges. Atomistic theory can catch the detailed behaviors of an individual atom by using molecular dynamics (MD) or quantum mechanics, although accurately, it is usually time-consuming. A multiscale method coupled MD and finite element (FE) is presented. To mesh the FE region automatically, an adaptive method based on the strain energy gradient is introduced to the multiscale method to constitute an adaptive multiscale method. Utilizing the proposed method, adhesive contacts between a rigid cylinder and an elastic substrate are studied, and the results are compared with full MD simulations. The process of FE meshes refinement shows that adaptive multiscale method can make FE mesh generation more flexible. Comparison of the displacements of boundary atoms in the overlap region with the results from full MD simulations indicates that adaptive multiscale method can transfer displacements effectively. Displacements of atoms and FE nodes on the center line of the multiscale model agree well with that of atoms in full MD simulations, which shows the continuity in the overlap region. Furthermore, the Von Mises stress contours and contact force distributions in the contact region are almost same as full MD simulations. The method presented combines multiscale method and adaptive technique, and can provide a more effective way to multiscale method and to the investigation on nanoscale contact problems.

关键词： adaptive multiscale method adhesive contact

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A near-complete genome assembly of the allotetrapolyploid Cenchrus fungigraminus(JUJUNCAO)provides insights into its evolution and C4 photosynthesis

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Plant Communications 2023年第5期4卷 324-341页

作者： Huakun Zheng Baiyu Wang Xiuting Hua ruiting Gao Yuhao Wang Zixin Zhang Yixing Zhang Jing Mei Yongji Huang Yumin Huang Hui Lin Xingtan Zhang Dongmei Lin Siren lan Zhongjian Liu Guodong Lu Zonghua Wang Ray Ming Jisen Zhang Zhanxi Lin National Engineering Research Center of JUNCAO Technology College of Life ScienceFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources Guangxi Key Laboratory of Sugarcane BiologyGuangxi UniversityNanning 530004GuangxiChina Center for Genomics Fujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyKey Laboratory of GeneticsBreeding and Multiple Utilization of CropsMinistry of EducationFujian Agriculture and Forestry UniversityFuzhou 350002China Fuzhou Institute of Oceanography Minjiang UniversityFuzhou 350108China

JUJUNCAO(Cenchrus fungigraminus;2n=4x=28)is a Cenchrus grass with the highest biomass production among cultivated plants,and it can be used for mushroom cultivation,animal feed,and biofuel ***,we report a nearly complete genome assembly of JUJUNCAO and reveal that JUJUNCAO is an allopolyploid that originated2.7 million years ago(mya).Its genome consists of two subgenomes,and subgenome A shares high collinear synteny with pearl *** also investigated the genome evolution of JUJUNCAO and suggest that the ancestral karyotype of Cenchrus split into the A and B ancestral karyotypes of *** transcriptome and DNA methylome analyses revealed functional divergence of homeologous gene pairs between the two subgenomes,which was a further indication of asymmetric DNA *** three types of centromeric repeat in the JUJUNCAO genome(CEN137,CEN148,and CEN156)may have evolved independently within each subgenome,with some introgressions of CEN156 from the B to the A *** investigated the photosynthetic characteristics of JUJUNCAO,revealing its typical C4 Kranz anatomy and high photosynthetic ***-ME and PEPCK appear to cooperate in the major C4 decarboxylation reaction of JUJUNCAO,which is different from other C4 photosynthetic subtypes and may contribute to its high photosynthetic efficiency and biomass *** together,our results provide insights into the highly efficient photosynthetic mechanism of JUJUNCAO and provide a valuable reference genome for future genetic and evolutionary studies,as well as genetic improvement of Cenchrus grasses.

关键词： genome assembly allotetrapolyploid centromere architecture evolutionary trajectory photosynthetic efficiency Cenchrus grass

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江苏省射阳县居民饮水情况与胃癌关联的病例对照研究

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中华预防医学杂志 2020年第8期54卷 892-896页

作者：郝瑞婷钱乐叶必雄张岚中国疾病预防控制中心环境与健康相关产品安全所北京100050

选择2014—2018年射阳县189例胃癌新发病例作为病例组,按照年龄、性别匹配189名其他未患胃癌人群作为对照组,开展居民饮水情况与胃癌关联的病例对照研究。多因素logistic回归模型结果显示,调整体重指数、家庭年收入、饮食口味、每月腌... 详细信息

选择2014—2018年射阳县189例胃癌新发病例作为病例组,按照年龄、性别匹配189名其他未患胃癌人群作为对照组,开展居民饮水情况与胃癌关联的病例对照研究。多因素logistic回归模型结果显示,调整体重指数、家庭年收入、饮食口味、每月腌菜食用量、每月辣椒食用量、每月豆制品食用量、经历不幸、患浅表性胃炎、胃癌家族史因素后,与10年前饮水末梢无污染源、饮用开水为主者相比,10年前饮水末梢有污染源、只喝生水者胃癌的患病风险较高[OR(95%CI)值分别为2.20(1.13~4.29)、6.12(1.25~29.93)];与饮水来源为自来水相比,饮用净水处理后水者胃癌患病风险较低[OR(95%CI):0.55(0.35~0.85)];每天饮水量较多者胃癌患病风险较低[OR(95%CI):0.67(0.48~0.92)]。

关键词：饮水病例对照研究胃癌

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纳观纹理表面摩擦过程的分子动力学模拟

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中国机械工程 2012年第19期23卷 2378-2383页

作者：南江红刘更佟瑞庭刘岚西北工业大学西安710072

采用分子动力学方法模拟了半球形刚性压头在单晶铜基体上的纳观黏着滑动接触过程。设计了不同纹理表面,研究了表面纹理方向和纹理密度对滑动摩擦力的影响。模拟结果表明:表面纹理密度小于50%时,0°和90°方向纹理表面的滑动摩擦力振幅较... 详细信息

采用分子动力学方法模拟了半球形刚性压头在单晶铜基体上的纳观黏着滑动接触过程。设计了不同纹理表面,研究了表面纹理方向和纹理密度对滑动摩擦力的影响。模拟结果表明:表面纹理密度小于50%时,0°和90°方向纹理表面的滑动摩擦力振幅较小,且45°方向纹理表面最易发生滑移塑性变形;纹理密度相差较大时,对于0°和90°方向纹理表面,滑动摩擦力随纹理密度的增大而增大;在较小的纹理密度下,0°和90°方向纹理表面的减摩效果优于光滑表面的减摩效果;纳观纹理表面的引入对滑动摩擦力的大小产生影响,但没有改变滑动摩擦力的波动周期。

关键词：纹理表面黏滑摩擦单晶铜分子动力学模拟

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纳观纹理表面相关参数对滑动摩擦过程的影响

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机械科学与技术 2013年第2期32卷 225-230页

作者：南江红刘更佟瑞庭刘岚西北工业大学机电学院西安710072

采用分子动力学方法研究了半球形刚性压头在单晶铜纹理表面上的纳观黏着滑动摩擦过程。对不同纹理密度下纹理形状和纹理深度对黏滑摩擦性能的影响进行了全面研究,通过对比分析不同纹理参数下的滑动摩擦力和基体变形,揭示了上述参数对纹... 详细信息

采用分子动力学方法研究了半球形刚性压头在单晶铜纹理表面上的纳观黏着滑动摩擦过程。对不同纹理密度下纹理形状和纹理深度对黏滑摩擦性能的影响进行了全面研究,通过对比分析不同纹理参数下的滑动摩擦力和基体变形,揭示了上述参数对纹理表面黏滑摩擦的影响规律。模拟结果表明:在相同的纹理密度下,柱状纹理表面的滑动摩擦力小于矩形纹理表面。相比矩形纹理,柱状纹理表面的结构稳定性较差,但纹理表面的结构稳定性随着纹理密度的增加而加强。在相同的纹理密度下,矩形纹理表面的滑动摩擦力随着纹理深度的增加而减小。

关键词：分子动力学纹理表面纹理形状纹理深度黏滑摩擦

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莴笋根部促生菌筛选与促生特性测定

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干旱地区农业研究 2020年第3期38卷 127-133页

作者：撖冬荣侯栋姚拓兰晓君朱瑞婷甘肃农业大学草业学院草业生态系统教育部重点实验室甘肃兰州730070 甘肃省农业科学院蔬菜研究所甘肃兰州730070

为获得莴笋(Lactuca sativa)根部优良促生菌株,为后续研制微生物接种剂(菌肥)提供优良菌种,以莴笋根系为对象,利用选择性培养基分离、筛选莴笋根系溶解有机溶磷、无机溶磷细菌和固氮细菌,测定其溶磷能力、固氮能力、分泌植物生长激素能... 详细信息

为获得莴笋(Lactuca sativa)根部优良促生菌株,为后续研制微生物接种剂(菌肥)提供优良菌种,以莴笋根系为对象,利用选择性培养基分离、筛选莴笋根系溶解有机溶磷、无机溶磷细菌和固氮细菌,测定其溶磷能力、固氮能力、分泌植物生长激素能力以及对植物病原菌的拮抗能力;对性能优良的菌株进行16S rDNA分子生物学鉴定。研究表明:莴笋根部分离到25株溶磷菌株,其溶解无机磷能力为60.83~290.66μg·mL^-1(菌株PGBA2溶磷量最高,为290.66μg·mL^-1),溶解有机磷的能力普遍较低,为8.12~71.87μg·mL^-1;分离出固氮菌株20株,固氮酶活性为8.37~371.54 nmol·h^-1·mL^-1(GNB6固氮酶活性最强,为371.54 nmol·h^-1·mL^-1);分离筛选分泌植物生长激素(IAA)菌株14株,分泌量为0.78~5.29μg·mL^-1(MGBD1分泌IAA的能力最强,为5.29μg·mL^-1);菌株MGNB4、MGBC3、PGBA2对黄瓜枯萎病(Fusarium oxysporum)有抑菌作用,抑菌率达到50%以上。对9株优良PGPR菌株进行分子生物学鉴定,菌株MGBC2、MGBC3、PGBA2为醋酸钙不动杆菌(Acinetobacter calcoaceticus),菌株MGNB3、MGNB4为华夏氏肠杆菌(Enterobacter huaxiensis),菌株MGBD1为铜绿假单胞菌(Pseudomonas brassicacearum),菌株GND5为枯草芽孢杆菌(Bacillus subtilis),菌株GNA6为气泡微细菌(Microbacterium aerolatum),菌株GNB6为放射型根瘤菌(Rhizobium radiobacter)。

关键词：莴笋植物根际促生菌溶磷细菌固氮细菌植物生长激素(IAA)

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影响食盐中碘含量检测结果准确性的主要因素

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农产品加工 2021年第10期 50-51,57页

作者：宋悦同瑞婷兰萌陕西省产品质量监督检验研究院陕西西安710048

碘是食盐重要的监测指标,研究了影响食盐中碘含量检测结果准确性的主要因素及试验过程中注意的事项。结果表明,对于加碘食盐而言,为保证检验结果的准确性,检测过程中应注意:①将碘盐研磨粉碎后均匀取样;②有效氯含量应适度过量,含量为3... 详细信息

碘是食盐重要的监测指标,研究了影响食盐中碘含量检测结果准确性的主要因素及试验过程中注意的事项。结果表明,对于加碘食盐而言,为保证检验结果的准确性,检测过程中应注意:①将碘盐研磨粉碎后均匀取样;②有效氯含量应适度过量,含量为3%较为适宜;③滴定过程中试样溶液滴定至浅黄色后再加入淀粉指示剂;④滴定终点以样液蓝色消失为终点,切勿直接滴定到澄清透明。

关键词：食盐碘有效氯含量

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婴幼儿米粉类辅食中亚硝酸盐测定方法的优化

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农产品加工 2021年第13期 70-71页

作者：同瑞婷宋悦兰萌陕西省产品质量监督检验研究院陕西西安710048

采用室温饱和硼砂超声提取法对样品中亚硝酸盐进行提取,与国标方法进行结果比较。结果表明,超声提取法能够在短时间内获得澄清滤液,回收率和RSD分别分布在93.5%~100.9%和1.35%~2.51%。经改进,过程简单、成本低而且准确度高,能满足定量... 详细信息

采用室温饱和硼砂超声提取法对样品中亚硝酸盐进行提取,与国标方法进行结果比较。结果表明,超声提取法能够在短时间内获得澄清滤液,回收率和RSD分别分布在93.5%~100.9%和1.35%~2.51%。经改进,过程简单、成本低而且准确度高,能满足定量试验测定的要求。

关键词：超声提取米粉亚硝酸盐

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