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甘肃岷县猫尾草叶斑病及其危害

草地学报 2025年第1期33卷 62-69页

作者：申琴徐秋蕊李应德段廷玉草种创新与草地农业生态系统全国重点实验室/农业部草牧业创新重点实验室/兰州大学草地农业教育部工程研究中心/兰州大学草地农业科技学院甘肃兰州730020

猫尾草(Phleum pratense)是一种多年生丛生型禾本科牧草,兼具抗寒耐湿、优质高产等特点,具有良好的饲用价值。病害是限制猫尾草生产的重要因素之一,目前尚缺少对猫尾草病害的系统研究。本研究以甘肃省岷县猫尾草为对象,调查了梯牧草枝孢... 详细信息

猫尾草(Phleum pratense)是一种多年生丛生型禾本科牧草,兼具抗寒耐湿、优质高产等特点,具有良好的饲用价值。病害是限制猫尾草生产的重要因素之一,目前尚缺少对猫尾草病害的系统研究。本研究以甘肃省岷县猫尾草为对象,调查了梯牧草枝孢(Cladosporium phlei)引致的猫尾草叶斑病发病动态,评定了病害危害损失。结果表明:梯牧草枝孢叶斑病主要在猫尾草生长中后期发生,田间发病率最高可达83.2%,病情指数达42.2。叶斑病显著影响了猫尾草的产量和品质,致使猫尾草鲜重显著减少50.6%,锌元素含量显著减少35.21%,以及叶绿素含量显著降低58.09%,苯丙氨酸、异亮氨酸、天冬氨酸、丙氨酸、色氨酸、甘氨酸与精氨酸含量显著减少了42.45%~67.47%,干重、粗蛋白含量和绿原酸含量分别损失了34.0%,45.7%和23.29%。综上,本研究发现梯牧草枝孢引致的猫尾草叶斑病是影响岷县猫尾草生产的重要病害,亟需研发防治技术。

关键词：猫尾草梯牧草枝孢叶斑病严重度饲草品质

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Numericals for total variation-based reconstruction of motion blurred images

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Applied Mathematics(A Journal of Chinese Universities) 2010年第3期25卷 367-373页

作者： xu qiu-bin Department of Mathematics Nanjing Audit University Nanjing 211815 China

In this paper image with horizontal motion blur, vertical motion blur and angled motion blur are considered. We construct several difference schemes to the highly nonlinear term △↓.（△↓u/√｜△↓｜^2＋β） of the total variation-based image motion deblurring problem. The large nonlinear system is linearized by fixed point iteration method. An algebraic multigrid method with Krylov subspace acceleration is used to solve the corresponding linear equations as in [7]. The algorithms can restore the image very well. We give some numerical experiments to demonstrate that our difference schemes are efficient and robust.

关键词： Motion blur difference scheme fixed point method algebraic multigrid method.

Salmonella Yrb D protein mediates invasion into the host by interacting with β2 integrin

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Journal of Integrative Agriculture 2025年第03期 1181-1197页

作者： Jun Cao Jinliang Wang Guanghui Dang Shihao Ding Yao Lu qiu xu Siguo Liu Shenye Yu State Key Laboratory for Animal Disease Control and Prevention Harbin Veterinary Research Institute Chinese Academy of Agricultural Sciences

Salmonella enterica serovar Typhimurium, the causative agent of gastroenteritis, is one of the most successful intracellular pathogens. Although certain host factors for Salmonella infection have been unveiled, the factors mediating Salmonella entry, particularly the invasion process, remain obscure. Here, we have unearthed β2 integrin,a crucial member of the integrin family, as an important host factor facilitating Salmonella invasion. It is demonstrated that overexpression of β2 integrin promotes Salmonella invasion, while the knockdown of β2 integrin significantly diminishes the extent of invasion. Moreover, Salmonella exhibits specific binding affinity towards β2 integrin, and the block of β2 integrin on cell surface substantially reduces the infection of cells in vitro. The ectodomain soluble protein of β2 integrin neutralized Salmonella infection both in cells(in vitro) and in mice(in vivo). Additionally, Salmonella protein YrbD directly interacts with β2 integrin to facilitate its invasion. To our knowledge, this study showed for the first time that the protein YrbD mediates Salmonella adhesion and internalization into host cells by interacting with β2 integrin. These findings not only broaden our understanding of the mechanisms underlying Salmonella entry, but also identify a prospective target for therapeutic control.

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Effects of alloying elements Mn,Mo,Ti,Si,P and C on the incubation period of void swelling in austenitic stainless steels

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Tungsten 2021年第1期3卷 3-19页

作者： Toshimasa Yoshiie qiu xu Institute for Integrated Radiation and Nuclear Science Kyoto UniversityOsaka 590‑0494Japan

Void swelling,which induces the degradation of the original properties of nuclear materials under high-energy particleirradiation,is an important *** incubation period,a transient stage before the steady void growth,determines the duration of service of nuclear *** experimental studies have been performed on void observations by transmission electron microscopy(TEM),which,however,has a resolution limit for the size of defect *** annihilation lifetime spectroscopy(PALS)enables the detection of small vacancy clusters,single vacancies,dislocations and *** use of these two methods provides complementary information toward detecting defect information in the incubation ***,defect structures during the incubation period in austenitic stainless steels,by means of PALS and TEM are *** role of alloying elements into determining the period is ***,the existing problems and research directions in this field are presented.

关键词： Austenitic stainless steels Void swelling Incubation period Neutron irradiation Positron annihilation lifetime spectroscopy

Zero-forcing dirty paper coding aided physical-layer network coding for MIMO two-way relaying channels with multiple users

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 53-58页

作者： GONG Peng xu Jie qiu Ling Personal Communication Network & Spread Spectrum Laboratory University of Science and Technology of China Hefei 230027 China

This article considers the two-way multiple-input multiple-output（MIMO） relaying channels with multiple users,in which multiple users are served simultaneously by the base station（BS） with the assistance of the *** transmission consists of only two phases,doubling the system throughout over traditional one-way half-duplex transmission.A zero-forcing dirty paper coding（ZFDPC） aided physical-layer network coding（PNC） scheme is proposed in this article and the achievable capacity of the ZFDPC aided PNC scheme is *** results show that the proposed scheme outperforms the previous decode-and-forward（DF） and zero-forcing beamforming（ZFBF） aided PNC scheme due to more degrees of freedoms and the advantage of ***,we analyze the effect of the imperfect channel state information（CSI） from RS to users at BS side to show the robustness of the proposed ZFDPC aided PNC scheme.

关键词： zero-forcing dirty paper coding MIMO physical-layer network coding two-way relaying multiuser diversity

Abundance and Dynamics of Soil Labile Carbon Pools Under Different Types of Forest Vegetation

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Pedosphere 2006年第4期16卷 505-511页

作者： JIANG Pei-Kun xu qiu-Fang Zhejiang Forestry College Lin＇an 311300 （China）

Soil organic matter (SOM) in forest ecosystems is not only important to global carbon (C) storage but also to sustainable management of forestland with vegetation types, being a critical factor in controlling the quantity and dynamics of SOM. In this field experiment soil plots with three replicates were selected from three forest vegetation types: broadleaf, Masson pine (Pinus massoniana Lamb.), and Chinese fir (Cunninghamia lanceolata Hook.). Soil total organic C (TOC), two easily oxidizable C levels (EOC1 and EOC2, which were oxidized by 66.7 mmol L-1 K_2Cr_2O_7 at 130-140℃and 333 mmol L-1 KMnO4 at 25℃, respectively), microbial biomass C (MBC), and water-soluble organic C (WSOC) were analyzed for soil samples. Soil under the broadleaf forest stored significantly higher TOC (P (?) 0.05). Because of its significantly larger total soil C storage, the soil under the broadleaf forest usually had significantly higher levels (P (?) 0.05) of the different labile organic carbons, EOC1, EOC2, MBC, and WSOC; but when calculated as a percentage of TOC each labile C fraction of the broadleaf forest was significantly lower (P (?)0.05) than one of the other two forests. Under all the three vegetation types temperature as well as quality and season of litter input generally affected the dynamics of different organic C fractions in soils, with EOC1, EOC2, and MBC increasing closely following increase in temperature, whereas WSOC showed an opposite trend.

关键词： dynamics forest soil labile organic C total organic C vegetation system

Panel data models with cross-sectional dependence: a selective review

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Applied Mathematics(A Journal of Chinese Universities) 2016年第2期31卷 127-147页

作者： xu qiu-hua CAI Zong-wu FANG Ying The Wang Yanan Institute for Studies in Economics MOE Key Laboratory of Econometrics (Xiamen University)Fujian Provincial Key Laboratory of Statistical ScienceXiamen University Department of Economics University of Kansas

In this review, we highlight some recent methodological and theoretical develop- ments in estimation and testing of large panel data models with cross-sectional dependence. The paper begins with a discussion of issues of cross-sectional dependence, and introduces the concepts of weak and strong cross-sectional dependence. Then, the main attention is primarily paid to spatial and factor approaches for modeling cross-sectional dependence for both linear and nonlinear （nonparametric and semiparametric） panel data models. Finally, we conclude with some speculations on future research directions.

关键词： Panel data models Cross-sectional dependence Spatial dependence Interactive fixed effects,Common factors.

Moving Objects with Transportation Modes:A Survey

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Journal of Computer Science & Technology 2019年第4期34卷 709-726页

作者： Jian-qiu xu Ralf Hartmut Güting Yu Zheng Ouri Wolfson College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 211106China Faculty of Mathematics and Computer Science University of HagenHagen 58097Germany JD Intelligent City Research Beijing 100176China Department of Computer Science University of Illinois at ChicagoChicago 60607U.S.A.

In this article,we survey the main achievements of moving objects with transportation modes that span the past *** an important kind of human behavior,transportation modes reflect characteristic movement features and enrich the mobility with informative *** make explicit comparisons with closely related work that investigates moving objects by incorporating into location-dependent semantics and descriptive *** exhaustive survey is offered by considering the following aspects:1)modeling and representing mobility data with motion modes;2)answering spatio-temporal queries with transportation modes;3)query optimization techniques;4)predicting transportation modes from sensor data,e.g.,GPS-enabled *** new and emergent issues concerning transportation modes are proposed for future research.

关键词： moving object transportation mode data model performance data generator

Time-Grating for the Generation of STUD Pulse Trains

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Chinese Physics Letters 2013年第4期30卷 85-87页

作者： ZHENG Jun WANG Shi-Wei xu Jian-qiu Key Laboratory for Laser Plasmas(Ministry of Education and Department of Physics Shanghai Jiao Tong UniversityShanghai 200240

Spike train of uneven duration or delay(STUD)pulses hold potential for laser-plasma interaction(LPI)control in laser *** technique based on time grating is applied to generate an STUD pulse *** grating,a temporal analogy of the diffraction grating,can control the pulse width,shape,and repetition rate easily through the use of electro-optical *** pulse width and repetition rate are given by the modulation frequency and depth of the phase modulation function in theory and numerical *** zero-chirped phase modulation is good for the compression effect of the time grating.A principle experiment of two pulses interfering is shown to verify the time grating function.

关键词： function. pulse repetition