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Engineering Multipedal DNA Walker on Paper for Sensitive Electrochemical Detection of Plant MicroRNA

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Chinese Journal of Chemistry 2022年第23期40卷 2808-2814页

作者： xiaojuan liu Junzhu Xiang Hao Cheng Yuying Wang Feng Li College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural UniversityQingdaoShandong 266109China College of Plant Health&Medicine Qingdao Agricultural UniversityQingdaoShandong 266109China

MicroRNAs (miRNAs) are vital regulators in both plants and animals. Therefore, it is highly desirable to develop portable and user-friendly biosensors for convenient and sensitive detection of miRNAs. Herein, a novel paper-based electrochemical biosensor was intelligently engineered for the detection of plant miRNA based on a smart DNA walking machine and λ-exonuclease (λ-Exo)-assisted target recycling amplification. Using TaMIR5086 as a target plant miRNA, the presence of TaMIR5086 could initiate the target recycling process and activate the DNA walker to move along the track on the paper. Then, numerous electroactive molecules-labeled single-strand DNA (ssDNA) would be released and adsorbed onto the surface of screen-printed electrode, generating a remarkably increased electrochemical signal. Benefitting from the dual amplification, the developed biosensor exhibits excellent analytical performance toward TaMIR5086 with a detection limit down to 0.37 pmol/L. Furthermore, the paper-based biosensor could be applied for the analysis of target miRNA in complex biological samples, which found great potential in the fields of miRNA analysis and plant biology research.

关键词： RNA recognition Electrochemistry Sensor DNA walker on paper Target recycling amplification

杉木ClOFP1基因的克隆、表达及单核苷酸多态性分析

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核农学报 2025年第1期39卷 19-28页

作者：王紫彤应威洋刘明彤刘晓娟林二培胡现铬黄华宏浙江农林大学亚热带森林培育国家重点实验室浙江临安311300

OFP基因家族在植物的生长发育中发挥重要调控作用。为探究ClOFP1在木质部形成过程中的作用,本研究通过克隆杉木ClOFP1基因,分析其表达模式,并开展该基因在杉木群体的单核苷酸多态性(SNP)及连锁不平衡(LD)分析。结果表明,ClOFP1基因的cDN... 详细信息

OFP基因家族在植物的生长发育中发挥重要调控作用。为探究ClOFP1在木质部形成过程中的作用,本研究通过克隆杉木ClOFP1基因,分析其表达模式,并开展该基因在杉木群体的单核苷酸多态性(SNP)及连锁不平衡(LD)分析。结果表明,ClOFP1基因的cDNA序列长1 648 bp,开放阅读框(ORF)长1 320 bp,在氨基酸序列的376~428位有卵形蛋白家族特有的OVATE结构域。系统进化树分析结果显示,ClOFP1蛋白与水稻、拟南芥中调控细胞伸长和次生壁形成的OsOFP19、AtOFP1、AtOFP4聚为一类。ClOFP1在幼嫩叶片和茎段中优势表达,随着叶片成熟和茎段木质化程度加深其表达量递减,幼叶中的表达量是老叶中的14倍。同时,在杉木木材中,ClOFP1主要在靠近树皮的边材区域表达,而在心边过渡区表达较弱。推测ClOFP1基因作为负调控因子,参与次生木质部的形成。共检测到ClOFP1基因内存在16个常见SNP位点,平均发生频率为1/103 bp。其中编码区域有11个SNP位点,分为7个同义突变和4个错义突变。7个地理种源的SNP多样性指数差异不显著,非同义突变多样性π_(ns)小于同义突变π_(s)。连锁不平衡分析结果发现,ClOFP1基因间的LD在875 bp左右长度内迅速消失,且SNPs具有3个较强的连锁不平衡区块。综上,ClOFP1的表达与杉木茎段木质化程度负相关,ClOFP1在不同无性系中SNP变异较为丰富,位点间的LD在较短序列长度内迅速消失,表明基于该基因的LD作图是可行的。本研究结果为深入解析ClOFP1功能和开展LD作图提供了重要依据。

关键词：杉木 OFP基因基因表达 SNP 连锁不平衡

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Comparative Study on Diagonal Strut Model of Infill Wall

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Structural Durability & Health Monitoring 2018年第3期12卷 169-187页

作者： Zhenling Chai Zixiong Guo xiaojuan liu Yunfan Jiang College of Civil Engineering Huaqiao UniversityXiamen361021China

The equivalent diagonal strut models of infill wall mainly include the single strut model and multi-strut ***,several equivalent strut models and their characteristics are introduced in this ***,model analysis and pushover analysis are carried out on infilled frame models with the aid of the software *** typical single strut models and a typical three-strut model are used to simulate the panel of the frames *** is indicated that the period reduction factor of the frame with a three-strut model is close to the value recommended by the current *** infill wall has great influence on the overall stiffness,bearing capacity and weak position of the *** stiffness and the bearing capacity of the infilled frame increase with the increase of the number of the infill *** unfilled story is the weak position of the infilled frame,and when the unfilled story at the bottom of the infilled frame,the seismic response of the upper infill layer decreases with the increasing of the number of unfilled story.

关键词： Infill wall equivalent strut model comparative study pushover analysis

Abusive Supervision and Neglect： The Effects of Leader-Based Perceived Insider Status and Perceived Organizational Support

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Frontiers of Business Research in China 2014年第4期8卷 550-570页

作者： Yuchuan liu Ning Xiao Jun liu xiaojuan liu Business School National University of Singapore Singapore 119245 Singapore School of Business Renmin University of China Beijing 100872 China Faculty of Business The Hong Kong Polytechnic University Hong Kong China

Researchers have noted various obvious behavioral outcomes caused by abusive supervision while overlooking hidden behaviors. We draw on self-determination theory to propose that abusive supervision leads to subordinates＇ hidden destructive behavior, namely neglect. This study examines the relationship by focusing on a three way interaction model. Using multi-wave design, we collected data in a Chinese leading petrochemical corporation. We found positive associations between abusive supervision and neglect. Such associations are influenced by subordinates＇ insider status and organizational support. Theoretical and practical implications, limitations and future research directions are discussed.

关键词： abusive supervision leader-based perceived insider status,organizational support neglect

Divalent Ytterbium Iodide Supported by β-Diketiminato Based Tridentate Ligand: Synthesis, Structure and Small Molecule Activation

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Chinese Journal of Chemistry 2020年第3期38卷 247-253页

作者： xiaojuan liu Li Xiang Chen Wang Bingwu Wang Xuebing Leng Yaofeng Chen State Key Laboratory of Organometllic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China Beiing National laboratory of Molecular Science State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Moleculor EngineeringPeking UniversityBeijing 100871Chino

Divalent ytterbium lodide[LYb(μ-I)(THF)]2(1;L=[MeC(NDIPP)CHC(Me)NCH2CH2NMe2]^-,DIPP=2,6-(iPr)2C6H3)was synthesized and its reactivity was *** 1 was synthesized by salt metathesis of Ybl2(THF)2 with the potassium salt of ligand(KL)in high *** the reactions with trimethylsil azide,azobenzene,sulfur and diphenyl disufide,complex 1 acts as a 2e *** the reaction with CO2,the central carbon atom ofβ-diketiminato backbone in 1 nuclephilcally attacks the CO2 molecule to give a divalent ytterbium carboxylate.

关键词： backbone potassium azide

Theoretical probe into universal tetrad effect for complexation discrepancy between lanthanide elements and organophosphoric extractant diethyl phosphoric acid

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Journal of Rare Earths 2024年第6期42卷 1142-1148,I0006页

作者： Haifeng Zheng Yanling Li Xuyi Zhang Jinglu Han Songsong Li Guolong Wu Qingshi liu xiaojuan liu Wuping Liao State Key Laboratory of Rare Earth Resources Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China University of Science and Technology of China Hefei230026China School of Chemistry and Chemical Engineering Nanchang UniversityNanchang330031China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China

The deep understanding of 4f-correlated electron motion behavior is experimentally limited due to similar physicochemical properties of rare earth elements(REEs).While the solvent extraction behavior originating from the continuous occupation of 4f electrons along the lanthanide family provides a particular platform to probe the 4f electrons motion behavior and its correlations to their versatile ***,the complexation between REEs and the prototypical extractant of diethyl phosphoric acid(DEP)was substantially studied based on quantum mechanical *** results firstly show that the average bond lengths between Ln and six coordinated oxygen atoms are consistent with lanthanide contraction phenomenon,and gadolinium break effect is also obviously ***,the"tetrad effect"is figured out based on the subtle discrepancy of 4f electrons occupation,namely La-Nd,Sm-Eu,Gd-Dy and ***,the main composition is 4f5d6p for La-Nd,while the discrepancy is due to the increasing electrons in the 5d shell,while it is 4f5d for *** Gd-Dy,their 4f orbitals accept little electrons and the donating electrons flow into 6s5d subshells due to the half-filled stability and the enhancement of shielding *** electrons donate into 5d6p subshells due to multiply electrons occupation of 4f orbitals for *** detailed analyses obviously clarify the"tetrad effect"along the lanthanide family due to the different variation of 4f orbital *** is expected that these microscopic understandings provide important guidance for the separation of REEs and the design of new extractants.

关键词： Theoretical calculation Rare earths 4f electron Tetrad effect Gadolinium break

Modeling the Warming Impact of Urban Land Expansion on Hot Weather Using the Weather Research and Forecasting Model: A Case Study of Beijing, China

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Advances in Atmospheric Sciences 2018年第6期35卷 723-736页

作者： xiaojuan liu Guangjin TIAN Jinming FENG Bingran MA Jun WANG Lingqiang KONG State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University School of Government Beijing Normal University CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences

The impacts of three periods of urban land expansion during 1990–2010 on near-surface air temperature in summer in Beijing were simulated in this study, and then the interrelation between heat waves and urban warming was assessed. We ran the sensitivity tests using the mesoscale Weather Research and Forecasting model coupled with a single urban canopy model,as well as high-resolution land cover data. The warming area expanded approximately at the same scale as the urban land expansion. The average regional warming induced by urban expansion increased but the warming speed declined slightly during 2000–2010. The smallest warming occurred at noon and then increased gradually in the afternoon before peaking at around 2000 LST—the time of sunset. In the daytime, urban warming was primarily caused by the decrease in latent heat flux at the urban surface. Urbanization led to more ground heat flux during the day and then more release at night, which resulted in nocturnal warming. Urban warming at night was higher than that in the day, although the nighttime increment in sensible heat flux was smaller. This was because the shallower planetary boundary layer at night reduced the release efficiency of near-surface heat. The simulated results also suggested that heat waves or high temperature weather enhanced urban warming intensity at night. Heat waves caused more heat to be stored in the surface during the day, greater heat released at night, and thus higher nighttime warming. Our results demonstrate a positive feedback effect between urban warming and heat waves in urban areas.

关键词： heat wave numerical simulation urbanization surface heat flux WRF UCM

Dialdehyde starch nanoparticles as antitumor drug delivery system:An in vitro,in vivo,and immunohistological evaluation

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Chinese Science Bulletin 2012年第24期57卷 3226-3232页

作者： XIAO SuYao liu XuanMing TONG ChunYi ZHAO LiChao liu xiaojuan ZHOU AiMei CAO Yong College of Food Science South China Agricultural University.Guangzhou 510642China Institute of Life Science and Biotechnology Hunan UniversityChangsha 410082China

Sustaining the release of therapeutic nanoparticles in a cell-, tissue-, or disease-specific manner is a potentially powerful technology. A new drug carrier-dialdehyde starch nanoparticle (DASNP) that can sustain the loading and release of 5-fluorouracil (5-Fu) antitumor drug is reported in this study. IR spectrophotometer and 1H NMR confirmed the formation of aldehyde groups, and scan electron microscope determinations showed that the dialdehyde starch nanoparticles obtained had an average diameter of 90 nm. 5-Fu, the model drug, was conjugated into nanoparticles by aldehyde groups. These 5-Fu-binding nanoparticles significantly enhanced breast cancer cell (MCF-7) inhibition in vitro compared with free 5-Fu. After subcutaneous 0 injection in the breast tumor-loaded rats, 5-Fu-DASNP exhibited remarkable tumor-inhibitory efficacy determined by measuring tumor weight in vivo. The tumor inhibition of 5-Fu-DASNP was 61%±6%, whereas that of free 5-Fu was only 42%±4%. Bcl-2/Bax immunohistochem-istry studies indicated that 5-Fu-DASNP remarkably induced tumor tissue necrosis. These results demonstrated that the DASNP prepared in this work is a potentially effective drug carrier.

关键词：抗癌药物纳米颗粒双醛淀粉体外抑制输送系统免疫组化体内 Bcl-2/Bax

A Q-switched erbium-doped fiber laser based on ZrS2 as a saturable absorber

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Chinese Optics Letters 2019年第8期17卷 21-25页

作者： Ping Hu Yan Huang Fangfang liu Ying liu Liping Guo Xiaolu Ge xiaojuan liu School of Physics and Optoelectronic Engineering Shandong University of Technology

A passively Q-switched erbium-doped fiber(EDF) laser is proposed and demonstrated utilizing a zirconium disulfide(ZrS2)-based saturable absorber(SA). ZrS2 nanosheets are prepared, whose modulation depth,saturation intensity, and nonsaturable absorbance are measured to be 14.7%, 0.34 MW/cm^2, and 17.4%, respectively. Then, a Q-switched EDF laser is implemented by the ZrS2-SA. The pulse repetition rate varies from 40.65 to 87.1 k Hz when the pump power changes from 55 to 345 mW. The shortest pulse width is 1.49 μs with pulse energy of 33.5 nJ. As far as we know, this is the shortest pulse width obtained by a ZrS2-SA so far.

关键词： EDF ZrS2 SA