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A resurfaced sensor NLR confers new recognition specificity to non-MAX effectors

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Journal of Integrative Plant Biology 2025年第1期67卷 11-14页

作者： Tongtong Zhu Xuefeng Wu Guixin Yuan Dongli Wang Vijai Bhadauria You-Liang Peng junfeng liu Xin Zhang The State Key Laboratory of Maize Bio-breeding Joint International Research Laboratory of Crop Molecular BreedingMinistry of Agriculture Key Laboratory for Crop Pest Monitoring and Green ControlCollege of Plant ProtectionChina Agricultural UniversityBeijing 100193China Joint International Research Laboratory of Crop Molecular BreedingChina Agricultural UniversityBeijing 100193China Frontiers Science Center for Molecular Design Breeding China Agricultural UniversityBeijing 100193China Sanya Institute of China Agricultural University Sanya 572025China

To defend against pathogens,plants have evolved an innate immune system,encompassing pattern-triggered immunity(PTI)and effector-triggered immunity(ETI).Nucleotide-binding leucine-rich repeat receptors(NLRs)detect pat... 详细信息

关键词： immunity specificity pattern

抗生素全细胞生物传感器的设计与应用研究进展

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生物工程学报 2025年第1期41卷 79-91页

作者：罗宇柯朱怡铃许健萍刘君凤音建华浙江工业大学生物工程学院浙江杭州310014

抗生素是由微生物产生或人工合成的具有杀菌或抑菌活性的化学物质,被广泛应用于临床治疗以及畜牧业和水产养殖行业中,使得土壤、水体和食品等环境中抗生素的残留问题非常突出;与此同时,抗生素耐药性问题日益严重,新型抗生素的开发迫在... 详细信息

抗生素是由微生物产生或人工合成的具有杀菌或抑菌活性的化学物质,被广泛应用于临床治疗以及畜牧业和水产养殖行业中,使得土壤、水体和食品等环境中抗生素的残留问题非常突出;与此同时,抗生素耐药性问题日益严重,新型抗生素的开发迫在眉睫。全细胞生物传感器可以利用微生物细胞将抗生素信号转换为可读信号,不仅能够简单快速、灵敏准确地对抗生素进行动态检测,还能有效地发现新型抗生素。本文对目前报道的抗生素全细胞生物传感器进行了全面的梳理和总结,将其分为特异型和广谱型两大类型,并重点阐述了两大类型抗生素生物传感器的设计原理与应用实例,为其他抗生素全细胞生物传感器的构建及应用提供了借鉴。

关键词：抗生素全细胞生物传感器耐药基因调控蛋白特异性灵敏度

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杆式折叠结构的设计与受力性能分析

建筑钢结构进展 2025年第2期27卷 64-73,122页

作者：刘俊锋刘艳芝朱德举王涛湖南大学土木工程学院长沙410082 山东天意高科技有限公司山东济宁272114

为了实现房屋的折叠与展开并满足其受力需求,在传统剪支铰折叠结构的基础上,提出一种新型杆式折叠结构。首先,对新型杆式折叠结构进行设计和优化,采用螺旋理论对其进行自由度分析。同时,建立高度为2.2 m的ABAQUS有限元模型,对其施加平... 详细信息

为了实现房屋的折叠与展开并满足其受力需求,在传统剪支铰折叠结构的基础上,提出一种新型杆式折叠结构。首先,对新型杆式折叠结构进行设计和优化,采用螺旋理论对其进行自由度分析。同时,建立高度为2.2 m的ABAQUS有限元模型,对其施加平面内竖向荷载,获得不同铰接约束次数、钢材强度等级、销轴孔径、槽钢立柱壁厚、杆件宽度条件下折叠结构的初始刚度、极限承载力和破坏模式。最后,对折叠结构进行稳定性分析,提出了设计建议。结果表明:当折叠结构展开后高宽比为1/√2时,可以达到最大折叠率;折叠结构展开过程中机构自由度为1,当折叠结构完全展开并施加一定铰接约束后结构自由度为负值;次要受力杆件、销轴孔径对结构初始刚度和极限承载力影响不大;提高钢材强度等级、槽钢立柱壁厚、主要受力构件宽度可提高结构初始刚度和极限承载力,但是其值过高时会导致结构发生失稳破坏;为避免结构失稳,可通过促进塑性铰形成和将特定杆件改为箱形截面两种途径来实现。

关键词：折叠结构有限元模拟螺旋理论荷载-位移曲线稳定性分析

Passive walker that can walk down steps:simulations and experiments

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Acta Mechanica Sinica 2008年第5期24卷 569-573页

作者： Ning liu junfeng Li Tianshu Wang School of Aerospace Tsinghua UniversityBeijing 100084 China

A planar passive walking model with straight legs and round feet was discussed. This model can walk down steps, both on stairs with even steps and with random steps. Simulations showed that models with small moments of inertia can navigate large height steps. Period-doubling has been observed when the space between steps grows. This period-doubling has been validated by experiments, and the results of experiments were coincident with the simulation.

关键词： Passive walking Period-doubling ,Simulation - Experiments Poincaré map ,Nonlinear dynamics

On a semilinear stochastic partial differential equation with double-parameter fractional noises

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Science China Mathematics 2014年第4期57卷 855-872页

作者： liu junfeng YAN LiTan Department of Mathematics Nanjing Audit University Department of Mathematics Donghua University

We study the existence,uniqueness and Hlder regularity of the solution to a stochastic semilinear equation arising from 1-dimensional integro-differential scalar conservation *** equation is driven by double-parameter fractional *** addition,the existence and moment estimate are also obtained for the density of the law of such a solution.

关键词： stochastic partial differential equations double-parameter fractional noises H61der regularity density of the law Malliavin calculus

An improved GC-ECD method for measuring atmospheric N_2O

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Journal of Environmental Sciences 2013年第3期25卷 547-553页

作者： Yuanyuan Zhang Yujing Mu Shuangxi Fang junfeng liu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Key Laboratory for Atmospheric Chemistry Centre for Atmosphere Watch and ServicesChinese Academy of Meteorological Sciences

Gas chromatography equipped with an electron capture detector （GC-ECD） has been widely used for measuring atmospheric N2O,but nonlinear response and the influence of atmospheric CO2 have been recognized as defects for *** original GCECD method using N 2 as carrier gas was improved by introducing a small flow rate of CO2 makeup gas into the ECD,which could well remedy the above *** N2O signal of the improved method was 4-fold higher than that of the original method and the relative standard deviation was reduced from 〉 1% to 0.31%.N2O concentrations with different CO2 concentrations （172.2×10-6-1722×10-6mol/mol） measured by the improved GC-ECD method were in line with the actual N2O ***,the N2O concentrations detected by the original method were largely biased with a variation range of-4.5%～7%.The N2O fluxes between an agricultural field and the atmosphere measured by the original method were greatly overestimated in comparison with those measured by the improved *** linear correlation （R2=0.9996） between the response of the improved ECD and N2O concentrations （93×10-9-1966×10-9mol/mol） indicated that atmospheric N2O could be accurately quantified via a single standard *** N2O concentrations comparatively measured by the improved method and a high precision GC-ECD method were in good agreement.

关键词： N2O GC-ECD CO2 exchange flux method comparison

Focused Widely Linear Beamforming

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Journal of Beijing Institute of Technology 2019年第4期28卷 744-749页

作者： Yougen Xu junfeng liu Zhiwen liu School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

The problem addressed in this paper concerns the extension of widely linear beamforming to the wideband case,developing a wide-focused linear beamformer for the extraction of a wideband second-order(SO)noncircular signal-of-interest(SOI)contaminated by uncorrelated interferences and *** the proposed beamformer,the beamforming array observation is first focused to adopt a standard linear minimum variance distortionless response(MVDR)*** augmented SOI steering vector then is obtained by estimating the SOI noncircularity parameter with the newly proposed oblique projection with an augmented sparse representation *** covariance matrix of the virtual interference,true interference and noise is further reconstructed using the newly presented complementary spatial spectrum *** wideband widely linear spatial filtering is finally realized via MVDR like *** performance of the proposed beamformer is verified by simulation.

关键词： array signal processing adaptive beamforming direction-of-arrival estimation noncircularity wideband

Levels,sources and health risks of carbonyls and BTEX in the ambient air of Beijing,China

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Journal of Environmental Sciences 2012年第1期24卷 124-130页

作者： Yujie Zhang Yujing Mu junfeng liu Abdelwahid Mellouki Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Centre National de Recherche Scientifique-Institut de Combustion AerothermiqueReactivite et Environnement(CNRS-ICARE)45071 Orleans cedex 02France

The atmospheric concentrations of carbonyls and BTEX （benzene,toluene,ethylbenzene,m,p-xylene and o-xylene） were measured simultaneously at a same sampling site in Beijing from September 2008 to August *** average concentrations of the total measured carbonyls during autumn,winter,spring,and summer were 37.7,31.3,39.7,50.5 μg/m 3,respectively,and maximal values for their diurnal variations usually happened at *** contrast to carbonyls,the average concentrations of the total measured BTEX during the four seasons were 27.2,31.9,23.2,19.1 μg/m 3,respectively,andminimal values for their diurnal variations always occurred in the early *** average concentration for carbonyls increased about 24% from September 2008–August 2009 to September 2009–August 2010,for BTEX,increased about 15%.Integrated life time cancer risks for three carcinogens （benzene,formaldehyde and acetaldehyde） in Beijing exceeded the value of 1E-06,and the hazard quotient （HQ） of non-cancer risk of exposure to formaldehyde exceeded unity.

关键词： carbonyls BTEX sources exposure and risk assessment Beijing

Rural vehicle emission as an important driver for the variations of summertime tropospheric ozone in the Beijing-Tianjin-Hebei region during 2014-2019

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Journal of Environmental Sciences 2022年第4期34卷 126-135页

作者： Yifei Song Yuanyuan Zhang junfeng liu Chenglong Zhang Chengtang liu Pengfei liu Yujing Mu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Tropospheric ozone(O_(3))pollution is increasing in the Beijing-Tianjin-Hebei(BTH)region despite a significant decline in atmospheric fine aerosol particles(PM_(2.5))in recent ***,the intrinsic reason for the elevation of the regional O_(3)is still *** this study,we analyzed the spatio-temporal variations of tropospheric O_(3)and relevant pollutants(PM_(2.5),NO_(2),and CO)in the BTH region based on monitoring data from the China Ministry of Ecology and Environment during the period of *** results showed that summertime O_(3)concentrations were constant in Beijing(BJ,0.06μg/(m^(3)·year))but increased significantly in Tianjin(TJ,9.09μg/(m^(3)·year))and Hebei(HB,6.06μg/(m3·year)).Distinct O_(3)trends between Beijing and other cities in BTH could not be attributed to the significant decrease in PM_(2.5)(from-5.08 to-6.32μg/(m3·year))and CO(from-0.053 to-0.090 mg/(m^(3)·year))because their decreasing rates were approximately the same in all the *** relatively stable O_(3)concentrations during the investigating period in BJ may be attributed to a faster decreasing rate of NO_(2)(BJ:-2.55μg/(m^(3)·year);TJ:-1.16μg/(m^(3)·year);HB:-1.34μg/(m3·year)),indicating that the continued reduction of NOx will be an effective mitigation strategy for reducing regional O_(3)*** positive correlations were found between daily maximum8 hr average(MDA8)O_(3)concentrations and vehicle population and highway freight transportation in ***,we speculate that the increase in rural NO_(x)emissions due to the increase in vehicle emissions in the vast rural areas around HB greatly accelerates regional O_(3)formation,accounting for the significant increasing trends of O_(3)in HB.

关键词： Tropospheric ozone The Beijing-Tianjin-Hebei region Spatio-temporal trends Rural vehicle emission