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Structural Characterization of Phosphatidylcholines at the Level of sn-and C=C Location

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Structural Characterization of Phosphatidylcholines at the L...

Learning from nature:Peptidomimetic of Hp1404 and identification of K1K8 as an improved anti-infectious peptide

2018年中国质谱学术大会（CMSC2018）

作者： Xue Zhao Xinwei Liu Wenbo cao Wenpeng Zhang xiaobo Xie Zheng Ouyang Yu Xia Department of Chemistry Tsinghua University Department of Precision Instrument Tsinghua University Department of Chemistry 4Weldon School of Biomedical EngineeringPurdue University

Phosphatidylcholines(PCs) are the major components of eukaryotic cell membrane and they play diverse roles in maintaining lipid homeostasis in biological systems1. PCs contain three structural building blocks, i.e., the glycerol backbone, fatty alkyl/acyl chains connected at the sn-1 and sn-2 of glycerol oxygen, and the phosphocholine head group. PCs could exist as mixtures of isomers of different fatty acyl composition, sn-position, and C=C location. Conventionally, identification of fatty acyl composition and sn-location is achieved by analyzing the fatty acyl anions or their losses as neutral ketenes from collision-induced dissociation(CID) of the PC anion adduct(e.g. acetate and formate)2. This method, however, suffers from limited accuracy in sn-isomer quantitation. Herein, we utilize strong binding between bicarbonate anion with the quaternary amine in PCs to promote new fragmentation pathway that enables facile analysis of sn-isomers of PC via CID. We further couple the Paternò–Büchi(PB)3 reaction with bicarbonate adduct formation to achieve sn-specific C=C location determination for PCs from lipid extract. CID of bicarbonate(A-) adduct of PC(M) in negative ion mode produces a distinct fragment peak from a radicaldirected fragmentation pathway, which has been verified by accurate mass measurement, MS3 CID, and MS3 CID-ozone induced dissociation. It contains intact sn-1 fatty acyl;the sn-2 fatty acyl is cleaved off, leaving a new C=C bond between C2-C3 on glycerol;the C3-hydroxyl is esterified by ethyl phosphate. Formation of such fragment ion is highly specific, thus termed as sn-1 diagnostic ion. Taking advantage of the sn-1 diagnostic ions, PC sn-positional isomers could be readily identified and quantified based on ion abundance ratios. In addition, sensitive quantitation of PC sn-isomers can be achieved from NLS of 121 Da, the most abundant fragment channel([M-AH-(CH3)3 N)]-). PB-MS4 CID of the bicarbonate adduct allows sn-position specific C=C location d

关键词： Phosphatidylcholine sn-isomer the Paternò-Büchì reaction C=C location shotgun lipidomics

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Learning from nature:Peptidomimetic of Hp1404 and identifica...

第12届生物毒素研究及医药应用学术大会

作者： Zhongjie Li Gaomin Liu Lanxia Meng xiaobo Xu Wenxin Li Yingliang Wu Zhijian cao State Key Laboratory of Virology College of Life SciencesWuhan University

As an alternative class of antimicrobial agent to overcome the drug resistant infections,antimicrobial peptides（AMPs） have gained significant ***,we designed and got an improved antimicrobial peptide K1K8 based on the molecular template of *** to the wild type Hp1404,K1K8 has an improved antibacterial spectra in vitro,a lower hemolytic activity,and an enhanced serum ***,K1K8 also decreases methicillin-resistant Staphylococcus aureus（MRSA） bacterial counts of the wounded region in the mouse skin infection ***,K1K8 does not induce both bacterial resistance and non-specific immune response ***,the peptide kills bacteria by disrupting the bacterial *** together,K1K8 exhibits the potential as the development of an anti-infection agent in the future.

关键词： Antimicrobial peptides Hemolysis Serum stability MRSA skin infection Resistance

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基于神经网络集成的阵地工程效能评估

兵器装备工程学报 2021年第4期42卷 156-161页

作者：曹林陈亮马小博陆军工程大学南京210007 中国人民解放军66072部队北京100044 军事交通学院汽车士官学校安徽蚌埠233011

针对单一神经网络存在精度低、泛化能力弱等问题,提出了基于神经网络集成的阵地工程效能评估模型。结合某合成旅阵地工程规划方案效能评估实例,由历史数据独立训练出若干个神经网络,选出多个精度较高且差异性较大的个体网络,组合构成神... 详细信息

针对单一神经网络存在精度低、泛化能力弱等问题,提出了基于神经网络集成的阵地工程效能评估模型。结合某合成旅阵地工程规划方案效能评估实例,由历史数据独立训练出若干个神经网络,选出多个精度较高且差异性较大的个体网络,组合构成神经网络集成。仿真实验结果表明,神经网络集成的评估性能明显优于最优的单个神经网络,且操作简单,评估快速,结果稳定,对于神经网络集成在评估领域中的推广应用具有积极意义。

关键词：神经网络集成阵地工程效能评估

In-orbit performance of ME onboard Insight-HXMT in the first 5 years

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Radiation Detection Technology and Methods 2023年第1期7卷 15-24页

作者： Ying Tan Xuelei cao Weichun Jiang xiaobo Li Bin Meng Wanchang Zhang Sheng Yang Tao Luo Yudong Gu Liang Sun Xiaojing Liu Yuanyuan Du Jiawei Yang Yanjun Xu Jinyuan Liao Yupeng Xu Fangjun Lu Liming Song Shuangnan Zhang Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Science19B Yuquan RoadShijingshan DistrictBeijing 100049China

Introduction The medium-energy X-ray telescope(ME)is a collimated X-ray telescope onboard the Insight hard X-ray modulation telescope(Insight-HXMT)*** has 1728 Si-PIN pixels readout using 54 low noise application-specific integrated circuits(ASICs).ME covers the energy range of 5–30 keV and has a total detection area of *** typical energy resolution of ME at the beginning of the mission is 3 keV at 17.8 keV(full width at half maximum,FWHM),and the time resolution is 255μ*** this study,we present the in-orbit performance of ME in its first 5 years of *** The performance of ME was monitored using onboard radioactive sources and astronomical X-ray *** carries six 241Am radioactive sources for onboard calibration,which can continuously illuminate the calibration *** long-term performance evolution of ME can be quantified using the properties of the accumulated spectra of the calibration *** addition,observations of the Crab Nebula and the pulsar were used to check the long-term evolution of the detection efficiency as a function of *** After 5 years of operation,742cm2 of the Si-PIN pixelswere stillworking *** peak positions of 241Am emission lines gradually shifted to the high-energy region,implying a slow increase in ME gain of 1.43%.A comparison of the ME spectra of the Crab Nebula and the pulsar shows that the E–C relations and the redistribution matrix file are still acceptable for most data analysis works,and there is no detectable variation in the detection efficiency.

关键词： Hard X-ray Calibration Detector In-orbit performance

生物炭负载纳米铁活化过硫酸盐去除土壤中的五氯联苯

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生态环境学报 2024年第2期33卷 282-290页

作者：丛鑫曹平王晓博辽宁工程技术大学环境科学与工程学院辽宁阜新123000

以污染土壤中检出量较高的PCB118为目标污染物,采用银杏叶提取液绿色合成纳米铁材料(nZVI)、玉米秸秆制备生物炭(BC),将nZVI负载在BC表面合成生物炭负载纳米零价铁复合材料(BC-nZVI),利用制备的BC-nZVI复合材料催化活化过硫酸盐(PS)去... 详细信息

以污染土壤中检出量较高的PCB118为目标污染物,采用银杏叶提取液绿色合成纳米铁材料(nZVI)、玉米秸秆制备生物炭(BC),将nZVI负载在BC表面合成生物炭负载纳米零价铁复合材料(BC-nZVI),利用制备的BC-nZVI复合材料催化活化过硫酸盐(PS)去除土壤中PCB118。主要探讨了在生物炭负载纳米零价铁活化过硫酸盐体系(BC-nZVI/PS)中复合材料BC-nZVI碳铁比及其投加量、PS浓度、pH值、温度等因素对PCB118去除速率的影响。结果表明,反应时间为24h时,碳铁比为2?1时BC-nZVI反应体系对土壤中PCB118去除效果优于其他3种比例。实验条件下,随着BC-nZVI的投加量由0.002 g增加到0.500 g,PS浓度由0.05 mol·L^(-1)增至0.35 mol·L^(-1),温度由15℃升高到45℃,土壤中PCB118的去除率分别增加了32.4%、10.6%及14.7%。随着溶液初始pH值由3升到9,土壤中PCB118的去除率降低了11.4%。单因素实验数据显示,在BC-nZVI的投加量为0.500 g,PS浓度为0.35 mol·L^(-1),pH值为3,温度为45℃的条件下,土壤中PCB118去除效果最佳。为分析不同因素及其交互作用对土壤中PCB118去除率的影响,采用Box-Behnken响应面法设计了三因素三水平试验,建立了PS浓度、温度和pH等3个变量的二次多项式回归模型,得到土壤中PCB118最佳去除条件为:PS浓度0.23 mol·L^(-1)、pH 3.11、温度45℃。在此条件下,土壤中的PCB118在BC-nZVI/PS体系中去除率为71.6%。实验验证结果与模型预测值的相对偏差<5%,表明可使用此模型对BC-nZVI/PS体系中PCB118的去除率进行预测。该研究可为土壤中PCB118污染治理提供一些基础数据,为绿色环保修复土壤中有机污染物提供理论参考。

关键词：五氯联苯生物炭植物提取液纳米零价铁过硫酸盐

New Method of Measuring the Positive-sequence Capacitance of T-connection Transmission Lines

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Energy and Power Engineering 2013年第4期5卷 941-944页

作者： Yuansen Zhang Demin Cui Qingtao cao Yongqiang Chai Peng Liu xiaobo Li Zhijian Hu Chuanqi Li Chengxue Zhang Dezhou Power Supply Company Shandong Electric Power Group Co. Dezhou China School of Electrical Engineering Wuhan University Wuhan China

A novel method of measuring the positive-sequence capacitance of T-connection transmission lines is proposed. The mathematical model of the new method is explained in detail. In order to obtain enough independent equations, three independent operation modes of T-connection transmission lines during the line measurement are introduced. The digital simulation results and field measurement results are shown. The simulation and measurement results have validated that the new method can meet the needs of measuring the positive-sequence capacitance of T-connection transmission lines. This method has been implemented in the newly developed measurement instrument.

关键词： T-connection Transmission Lines Line Parameter Positive-sequence Capacitance Measurement

贵金属纳米复合材料电致化学发光传感器在食品重金属检测中的研究进展

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食品科学 2024年第22期45卷 269-279页

作者：王秀雯袁景利张艳张晓波曹际娟大连民族大学生命科学学院生物技术与资源利用教育部重点实验室辽宁大连116600 国家粮食和物资储备局标准质量中心北京100834

随着工业化的加速,重金属污染问题日益严重,对人类健康构成了巨大的威胁。近年来,各种生物传感器被广泛用于重金属检测,其中,电致化学发光传感器因其高灵敏度、快速响应和实时检测能力而受到研究者的关注。贵金属纳米复合材料因其独特... 详细信息

随着工业化的加速,重金属污染问题日益严重,对人类健康构成了巨大的威胁。近年来,各种生物传感器被广泛用于重金属检测,其中,电致化学发光传感器因其高灵敏度、快速响应和实时检测能力而受到研究者的关注。贵金属纳米复合材料因其独特的物理化学性质,在提高传感器性能方面发挥着重要作用。本文总结了基于贵金属纳米复合材料的电致化学发光传感器在重金属检测中的最新研究进展,强调了材料在提高传感器灵敏度等方面的作用,讨论了其在重金属检测中的性能表现,探讨了传感器的设计原理、特异性等,并展望了未来通过技术进步提升传感器性能以及优化微流控平台的应用,以期为食品安全检测的挑战提供更有效的解决方案。

关键词：重金属电致化学发光传感器贵金属纳米复合材料快速检测传感性能

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金属诱导制备纳米晶硅薄膜的研究进展

材料导报 2023年第21期37卷 34-40页

作者：王宁马晓波侯毅郑富曹志杰宁夏大学物理与电子电气工程学院银川750021

纳米晶硅是纳米尺度无定形态的硅晶粒,具备体硅所不具有的新颖光电性能,具有显著的量子限域效应,是发光半导体、光伏发电等领域中的关键材料。实验上,非晶硅通过气氛退火获得晶化的纳米晶硅,本质上破坏了非晶硅中的Si-Si共价键,局域生... 详细信息

纳米晶硅是纳米尺度无定形态的硅晶粒,具备体硅所不具有的新颖光电性能,具有显著的量子限域效应,是发光半导体、光伏发电等领域中的关键材料。实验上,非晶硅通过气氛退火获得晶化的纳米晶硅,本质上破坏了非晶硅中的Si-Si共价键,局域生核形成纳米晶硅,因此,晶化温度近达1000℃,晶化时间长达数小时。金属诱导法通过金属与非晶硅直接接触,促使Si与金属在400~600℃的低温条件下形成离子键,弱化了界面处的Si-Si键,为纳米晶硅提供成核位点,有效降低了纳米晶硅的晶化温度并缩短晶化时间。同时,不同诱导金属(如Ni、Pt、Pd、Cu、Au、Al和Ag)与界面处Si原子的结合方式不同,诱导非晶硅晶化的机制和晶化效果不同。基于此,本文归纳汇总了Ni、Al、Cu、Au、Co几种常见金属以及Ag-Cu和Ni-Cu两种合金诱导a-Si晶化的诱导机制、诱导特征及晶化条件,可为纳米晶硅薄膜的制备工艺提供有益参考。

关键词：金属诱导法非晶硅纳米晶硅薄膜低温诱导

SARS-CoV-2 Epitopes following Infection and Vaccination Overlap Known Neutralizing Antibody Sites

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Research 2022年第2期2022卷 71-84页

作者： Li Yang Te Liang Lane M.Pierson Hongye Wang Jesse K.Fletcher Shu Wang Duran Bao Lii Zhang Zhen Huang Wenshu Zheng Xiaomei Zhang Heewon Park Yuwen Li James E.Robinson Amy K.Fechan Christopher J.Lyon Jing cao Lisa A.Morici Chenzhong Li Chad J.Roy xiaobo Yu Tony Hu Center for Cllular and Molecular Diagnostics Tulane University Schoo of Medicine1430 Tulane AveNew OrleansLA 70112USA Department of Biochemisty and Molecular Biology Tulane University School of Medicine1430 Tulane AveNew OrleansLA 70112USA Beijing Key Laboratory for Forest Pest Control Bejjing Foresiry UniersilyBeijing 10083.China State Key Laboratory of Proteommics Beijing Protcome Resarch CenterNattional Center for Protein Sciences-Beiing(PHOENIX Center)Beijing Institute of LijfeomicsBeijing 102206China Hayward Genetis Cener Department of PediatricsTulane Universily School of Medicine1430 Tulane AveNew OrleansLA 70112USA Department of Pediatrics Tulane Uhriversity School of Medicine1430 Ttulane AveNew OrleansLA 70112USA Infectious Disease Depariment Ochsner Clinic FoundationNew OrleansLA 70121USA Universty of Texas Souhwestern Medical Cener 5323 Harry Himes BlvdDallasTX 75390USA Department of Microbiology Imruolog Tulane Untiversity School of Medicine 1430 Tulane AveNew OrleansLA 70112USA Division of Microbiology Tulane National Primate Research Center18703 Three Rivers RoadCovingtonLA 70433USA

Identification of epitopes targeted following virus infection or vaccination can guide vaccine design and development of therapeutic interventions targeting functional sites,but can be ***,we employed peptide microarrays to map linear peptide epitopes(LPEs)recognized following SARS-CoV-2 infetion and *** detected by nonhuman primate(NHP)and patient IgMs after SARS-CoV-2 infection extensively overlapped,localized to functionally important virus regions,and aligned with reported neutralizing antibody binding *** LPE overlap occurred atfter infection and vaccination,with LPE clusters specifc to each stimulus,where strong and conserved LPEs mapping to sites known or likely to inhibit spike protein ***-specifc LPEs tended to map to sites known or likely to be afected by structural changes induced by the proline substitutions in the mRNA vaccine's S *** LPEs to regions of known functional importance in this manner may acelerate vaccine evaluation and discovery of targets for sile secific therapeutic interventions.

关键词： vaccine Antibody likely