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山西省晋中和晋南肉牛捻转血矛线虫的核酸检测

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动物医学进展 2024年第9期45卷 141-144页

作者：贺渊惠刘亚亚马志雅郑文斌谢世臣刘卿朱兴全高文伟山西农业大学动物医学学院山西太谷030801 云南农业大学动物医学院云南省高校兽医公共卫生重点实验室云南昆明650201

为了解山西省部分地区肉牛捻转血矛线虫的感染类型和感染率,从山西省晋中(祁县、太谷区)和晋南(稷山县)3个地区采集431份肉牛粪便样本,对捻转血矛线虫ITS-2部分序列进行扩增、测序及鉴定,分析山西省部分地区肉牛捻转血矛线虫的感染情况... 详细信息

为了解山西省部分地区肉牛捻转血矛线虫的感染类型和感染率,从山西省晋中(祁县、太谷区)和晋南(稷山县)3个地区采集431份肉牛粪便样本,对捻转血矛线虫ITS-2部分序列进行扩增、测序及鉴定,分析山西省部分地区肉牛捻转血矛线虫的感染情况。结果显示,在431份检测样品中,7份粪便样品中扩增出捻转血矛线虫ITS-2序列,且序列完全一致,总感染率为1.62%;阳性样品均来源于6~12月龄公牛,晋中地区肉牛感染率为2.43%(5/206),晋南地区肉牛感染率为0.89%(2/225);晋中地区阳性样品均来源于祁县,来源于太谷区的样品中无阳性。序列比对结果显示,扩增出的序列与GenBank中来源于羊的捻转血矛线虫序列相似度为99.62%,说明感染牛与羊的捻转血矛线虫为同一种。表明山西两地区均存在捻转血矛线虫感染,感染率较低,感染牛的捻转血矛线虫为羊种捻转血矛线虫。

关键词：肉牛捻转血矛线虫 ITS-2 检测

茅苍术转录因子AlWRKY65的克隆与功能初探

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药学学报 2024年第5期59卷 1494-1502页

作者：管凤雅刘巍玮迟凯文曾凯玲谢晋查良平安徽中医药大学药学院安徽合肥230012 安徽医科大学药学院安徽合肥230032

WRKY转录因子是植物特有的一类转录因子,在植物多种生理过程中发挥重要的作用。本研究以茅苍术转录组数据为依据,对茅苍术AlWRKY基因与AlTPS基因的FPKM值进行相关性分析,结合分析结果筛选出与AlTPS1、AlTPS6基因表达量具有显著正相关性... 详细信息

WRKY转录因子是植物特有的一类转录因子,在植物多种生理过程中发挥重要的作用。本研究以茅苍术转录组数据为依据,对茅苍术AlWRKY基因与AlTPS基因的FPKM值进行相关性分析,结合分析结果筛选出与AlTPS1、AlTPS6基因表达量具有显著正相关性且FPKM值相对较高的候选基因AlWRKY65,对该候选基因进行克隆,获得AlWRKY65基因的开放阅读框(ORF),分析其编码蛋白的相关信息并进行基因表达研究。研究结果表明,AlWRKY65包含一个681bp的开放阅读框,编码226个氨基酸。AlWRKY65基因编码的氨基酸序列与向日葵HaWRKY65、莴苣LsWRKY65等植物基因编码的氨基酸序列具有较高同源性;该蛋白具有1个WRKYGQK保守结构域,属于WRKY基因家族的第IIe组;系统进化树分析显示,茅苍术AlWRKY65与洋蓟CcWRKY65蛋白亲缘关系较近;运用实时荧光定量PCR检测AlWRKY65基因在2个产地不同组织中的表达水平,结果表明,不同产地的茅苍术AlWRKY65基因具有组织表达差异性,均在叶片中表达量较高;在茉莉酸甲酯(MeJA)诱导处理48 h内,AlWRKY65基因的表达量下调;亚细胞定位和转录自激活活性分析显示,AlWRKY65定位于细胞核,不具有自激活活性。这些结果为进一步研究AlWRKY65在茅苍术中的生物学功能提供参考。

关键词：茅苍术 WRKY转录因子基因克隆表达分析亚细胞定位

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发射光谱法诊断空气电弧的稳态电子密度分布

高压电器 2024年第3期60卷 144-150页

作者：刘广义曹蕤卢阳姚斯立高文孙昊宇文博西安高压电器研究院股份有限公司西安710077 西安交通大学电气学院西安710049

空气电弧是一种常见的等离子体,对其稳态阶段的微观参数进行研究,对准确把握等离子体内部的反应机制有重要意义。发射光谱法是一种成熟的诊断等离子体电子密度的技术,具有非接触式测量、瞬态探测、灵敏度高、响应速度快、仪器简单等优... 详细信息

空气电弧是一种常见的等离子体,对其稳态阶段的微观参数进行研究,对准确把握等离子体内部的反应机制有重要意义。发射光谱法是一种成熟的诊断等离子体电子密度的技术,具有非接触式测量、瞬态探测、灵敏度高、响应速度快、仪器简单等优点。文中以H_(α)656.28 nm谱线做特征谱线,以石墨为电极材料在250 A、200 V的条件下对空气电弧进行发射光谱的测量,对实验获得的发射光谱作阿贝尔反变换和佛克脱线型拟合,反卷积得到斯塔克展宽,最终获得空气电弧电子数密度的径向分布。同时利用汤姆逊散射法测量相同参数条件下空气电弧的电子数密度以验证发射光谱法测量结果的正确性,经验证两种方法的测量结果具有良好的一致性。该实验为空气电弧等离子体电子数密度的测量提供了参考思路和方法。

关键词：气体电弧发射光谱法汤姆逊散射稳态等离子体

Stationarity in the variability of arid precipitation:A case study of aridCentral Asia

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Advances in Climate Change Research 2021年第2期12卷 172-186页

作者： YAO Jun-qiang CHEN Jing ZHANG Tong-wen DILINUER Tuoliewubieke MAO Wei-Yi Institute of Desert Meteorology China Meteorological AdministrationUrumqi830002China

Precipitation is particularly scarce in arid Central Asia(CA),and is expected to be severely impacted by future warming,and the assessmentof the stationarity of precipitation variability is important for managing surface water resources in this *** this study,we investigated thestatistics of stationarity in the totals and extremes of precipitation in CA based on the longest observational records(1881e2006),tree-ringreconstructed records(1756e2012 and 1760e2015),and the Coupled Model Intercomparison Project 5(CMIP5)simulations,applying theautocorrelation function and testing criteria established based on the statistical definitions of *** analyzed the longest daily pre-cipitation record(Tashkent station,1881e2006)and found that the autocorrelation coefficient of the precipitation totals(PRCPTOT)and annualmaximum 1-day precipitation amount(Rx1day)were statistically insignificant for all lags,implying stationary ***,nearly allthe Global Historical Climatology Network-Daily Database(GHCN-D)observatory sites(1925e2005)indicated likely stationary *** records were also indistinguishable from a random *** the CMIP5 models,the simulated and projected PRCPTOT closelyapproximated a purely random process;however,the projected Rx1day maintained non-stationary means in most of the models under therepresentative concentration pathway(RCPs),implying that extreme events would increase in the *** mean precipitation changes(DP)can be expressed as an exponential function depending on the length of the successive mean periods(m)and variance(s2).TheDPof the nextdecade is projected to be within±14.8%of the previous decades mean annual PRCPTOT over *** higher the RCPs,the higher theDP *** results show that the detection and prediction of precipitation change will be challenging in arid CA.

关键词： Stationarity Precipitation Extreme precipitation Variance Central Asia

生物启发的细菌表面人造矿物壳:通过仿生矿化保护活细胞

维普期刊数据库评论

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微生物学报 2024年第6期64卷 2133-2143页

作者：郑莹玲刘瑜谢鑫石美玲谢雯曾飒曾晓雪孟涛西南交通大学生命科学与工程学院四川成都610031 广州栋方生物科技股份有限公司广东广州510800

【目的】生物启发的细菌表面仿生矿化人造矿物壳被用于保护活细胞。【方法】将细菌限制在坚固而完整的矿物壳中,有限的物理空间和物质交换使其暂时进行休眠,降低长期保存期间的活力损失以及提高在各种极端环境中的生存能力,并且能够通... 详细信息

【目的】生物启发的细菌表面仿生矿化人造矿物壳被用于保护活细胞。【方法】将细菌限制在坚固而完整的矿物壳中,有限的物理空间和物质交换使其暂时进行休眠,降低长期保存期间的活力损失以及提高在各种极端环境中的生存能力,并且能够通过酸去除矿物壳而重新激活细菌。【结果】相较于未仿生矿化的细菌(EcN),矿化细菌(EcN@CaCO3)在32 d的储存实验中活力最高提升262倍;在pH 2.5的强酸环境中存活率提高837倍;在pH 12.0的强碱环境中存活率提高171倍;在80°C的高温条件下存活率提高59.1倍;甚至在抗生素溶液中,EcN@CaCO3中细菌的存活率是EcN的729.7倍。【结论】本研究利用仿生矿化提高了细菌的保存稳定性,使其能在酸刺激下去除涂层恢复活性,也能在极端环境下保留细菌的活力,为微生物在环境生态、食品制造和生物医药等领域的应用提供研究基础。

关键词：细菌生物启发仿生矿化休眠与激活耐受性

Quantitative rescattering theory for nonsequential double ionization

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Chinese Physics B 2019年第12期28卷 14-32页

作者： Zhangjin Chen Fang liu Hua wen Department of Physics College of ScienceShantou University UniversityShantou 515063China

We review the recently improved quantitative rescattering theory for nonsequential double ionization, in which the lowering of threshold due to the presence of electric field at the time of recollision has been taken into account. First,we present the basic theoretical tools which are used in the numerical simulations, especially the quantum theories for elastic scattering of electron as well as the processes of electron impact excitation and electron impact ionization. Then,after a brief discussion about the properties of the returning electron wave packet, we provide the numerical procedures for the simulations of the total double ionization yield, the double-to-single ionization ratio, and the correlated two-electron momentum distribution.

关键词： laser-induced recollision nonsequential double ionization quantitative rescattering model

Symmetry Groups and New Exact Solutions to （2＋1）-Dimensional Variable Coefficient Canonical Generalized KP Equation

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Communications in Theoretical Physics 2007年第3X期48卷 405-410页

作者： ZHANG Li-Hua liu Xi-qiang BAI Cheng-Lin Department of Mathematics Dezhou College Dezhou 253023 China School of Mathematical Sciences Liaocheng University Liaocheng 252059 China School of Physics Science and Information Engineering Liaocheng University Liaocheng 252059 China

In this paper, the modified CK＇s direct method to find symmetry groups of nonlinear partial differential equation is extended to （2＋1）-dimensional variable coeffficient canonical generalized KP （VCCGKP） equation. As a result, symmetry groups, Lie point symmetry group and Lie symmetry for the VCCGKP equation are obtained. In fact, the Lie point symmetry group coincides with that obtained by the standard Lie group approach. Applying the given Lie symmetry, we obtain five types of similarity reductions and a lot of new exact solutions, including hyperbolic function solutions, triangular periodic solutions, Jacobi elliptic function solutions and rational solutions, for the VCCGKP equation.

关键词： (2+1)-dimensional variable coefficient canonical generalized KP (VCCGKP) equation modified CK's'direct method symmetry groups Lie symmetry similarity reductions new exact solutions

Microstructure and Mechanical Properties in Friction Stir Welded Thick Al–Zn–Mg–Cu Alloy Plate

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Acta Metallurgica Sinica(English Letters) 2022年第8期35卷 1329-1342页

作者： Fei qiang wen Wang Ke Qiao Pai Peng Ting Zhang Xiao-Hu Guan Jun Cai qiang Meng Hua-Xia Zhao Kuai-She Wang School of Metallurgical Engineering National and Local Joint Engineering Research Center for Functional Materials ProcessingXi'an University of Architecture and TechnologyXi'an 710055China Northwest Institute for Non-Ferrous Metal Research Xian 710016China AVIC Manufacturing Technology Institute Bejing 100024China Beijing FSW Technology Co.Ltd Bejing 101107China

In this work, 20-mm-thick aluminum-alloy plates were joined via friction stir welding. The temperature gradient was reduced by reducing the surface welding heat input to achieve uniformity of the mechanical properties across the thick plate joints. The welding temperature was measured using thermocouples. The microstructures were observed via electron backscatter diff raction and transmission electron microscopy. The tensile properties of the samples sliced along the thickness direction of the joint were evaluated. The results show that the highest welding peak temperature is 430℃ on the advancing side on the top surface of the joint. The grain size gradually decreased along the thickness direction, and grain refi nement was due to the combination of continuous, discontinuous, and geometric dynamic recrystallization. The tensile properties of the sliced samples were found to be uniform, and the ultimate tensile strength reached 62% of that of the base metal. The main strengthening mechanism of the Al–Zn–Mg–Cu alloy joints consists of precipitation strengthening. In addition, the η ` → η phase transition and grain coarsening in the heat-affected zone were found to be responsible for the fracture of the joints.

关键词： Friction stir welding Aluminum alloy thick plate Dynamic recrystallization Mechanical properties Precipitated phase

Saturated output feedback tracking control for robot manipulators via fuzzy self-tuning

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第12期11卷 956-966页

作者： Hua-shan liu Shi-qiang ZHU Zhang-wei CHE State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China College of lnformation Science and Technology Donghua University Shanghai 201620 China

This paper concerns the problem of output feedback tracking (OFT) control with bounded torque inputs of robot manipulators, and proposes a novel saturated OFT controller based on fuzzy self-tuning proportional and derivative (PD) gains. First, aiming to accomplish the whole closed-loop control with only position measurements, a linear filter is involved to generate a pseudo velocity error signal. Second, different from previous strategies, the arctangent function with error-gain is applied to ensure the boundedness of the torque control input, and an explicit system stability proof is made by using the theory of singularly perturbed systems. Moreover, a fuzzy self-tuning PD regulator, which guarantees the continuous stability of the overall closed-loop system, is added to obtain an adaptive performance in tackling the disturbances during tracking control. Simulation showed that the proposed controller gains more satisfactory tracking results than the others, with a better dynamic response performance and stronger anti-disturbance capability.

关键词： Robot Tracking systems Bounded torque input Fuzzy control Output feedback