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Comprehensive Functional Analysis of the Catalase Gene Family in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2008年第10期50卷 1318-1326页

作者： Yan-Yan Du peng-cheng wang Jia Chen Chun-peng Song State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100094 China Laboratory of Plant Stress Biology Department of Biology Henan University Kaifeng 475001 China

In Arabidopsis, catalase （CAT） genes encode a small family of proteins including CAT1, CAT2 and CAT3, which catalyze the decomposition of hydrogen peroxide （H2O2） and play an important role in controlling homeostasis of reactive oxygen species （ROS）. Here, we analyze the expression profiles and activities of three catalases under different treatments including drought, cold, oxidative stresses, abscisic acid and salicylic acid in Arabidopsis. Our results reveal that CAT1 is an important player in the removal of H2O2 generated under various environmental stresses. CAT2 and CAT3 are major H2O2 scavengers that contribute to ROS homeostasis in light or darkness, respectively. In addition, CAT2 is activated by cold and drought stresses and CAT3 is mainly enhanced by abscisic acid and oxidative treatments as well as at the senescence stage. These results, together with previous data, suggest that the network of transcriptional control explains how CATs and other scavenger enzymes such as peroxidase and superoxide dismutase may be coordinately regulated during development, but differentially expressed in response to different stresses for controlling ROS homeostasis.

关键词： catalase isozymes reactive oxygen species stress transcription.

Bronsted acidic ionic liquid [C_3SO_3HDoim]HSO_4 catalyzed one-pot three-component Biginelli-type reaction: An efficient and solvent-free synthesis of pyrimidinone derivatives and its mechanistic study

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Chinese Chemical Letters 2016年第2期27卷 226-230页

作者： Zhi-Lei Zhou peng-cheng wang Ming Lu School of Chemical Engineer Nanjing University of Science & Technology

A series of Bronsted acidic ionic liquids（ILs） were prepared and used for Biginelli-type condensation reaction among aromatic aldehydes, urea or thiourea and cyclopentanone. Through this reaction, the synthesis of various pyrimidinones could be achieved. Of interest, it was found that the reaction was efficiently catalyzed by a novel, eco-friendly functionalized IL [C3SO3HDoim]HSO4, which could be reused for at least 7 times without significantly loss of catalytic activity. The reaction proceeded efficiently at 80℃ to afford the desired products in good yield（up to 96%）. In addition, a possible mechanism that accounted for the IL [C3SO3HDoim]HSO4-catalyzed reaction was proposed.

关键词： Bronsted acidic ionic liquids Catalysis Biginelli-type reaction Pyrimidinone Organic synthesis Applied chemistry

Interfacial friction effects on sealing performances of elastomer packer

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Petroleum Science 2024年第3期21卷 2037-2047页

作者： peng-cheng wang Ming-Hui Chen Jim Jenkinson Yong-Xin Song Li Sun Department of Mechanical Engineering University of HoustonHoustonTX77024USA Guren Nanomaterials Suzhou215127JiangsuChina Department of Marine Engineering Dalian Maritime UniversityDalian116026LiaoningChina

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic *** practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and *** previous studies,the impact of friction forces on sealing performance is often *** work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing *** first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac *** we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after *** the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug *** addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial *** study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

Analysis of Global Expression Profiles of Arabidopsis Genes Under Abscisic Acid and H2O2 Applications

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Journal of Integrative Plant Biology 2006年第1期48卷 62-74页

作者： peng-cheng wang Yan-Yan Du Guo-Yong An Yun Zhou Chen Miao Chun-peng Song Laboratory of Plant Stress Biology Department of Biology Henan University Kaifeng 475001 China

To gain insight into the coordination of gene expression profiles under abscisic acid （ABA） and H2O2 applications, global changes in gene expression in response to ABA and H2O2 in Arabidopsis seedlings were investigated using GeneChip （Santa Clara, CA, USA） arrays. Among over 24 000 genes present in the arrays, 459 tran- scripts were found to be significantly increased, whereas another 221 decreased following H2O2 treatment compared with control. Similar to treatment with H2O2, ABA treatment elevated the transcription of 391 genes and repressed that of 322 genes. One hundred and forty-three upregulated genes and 75 downregulated genes were shared between the two treatments and these genes were mainly involved in metabolism, signal transduction, transcription, defense, and resistance. Only two genes, which encode an APETALA2/dehydra- tion-responsive element binding protein （AP2/DREBP） family transcriptional factor and a late embryogenesis- abundant protein, were downregulated by H202, but upregulated by ABA. These results suggest that, similar to ABA, H202 plays a global role in gene transcription of Arabidopsis seedlings. The transcriptional responses induced by the application of exogenous ABA and H2O2 overlapped substantially. These two treatments regulated most of the downstream genes in a coordinated manner.

关键词： abscisic acid gene expression hydrogen peroxide microarray.

Improvement in Tol2 transposon for efficient large-cargo capacity transgene applications in cultured cells and zebrafish(Danio rerio)

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Zoological Research 2024年第3期45卷 567-574页

作者： peng-cheng wang Hao Deng Rang Xu Jiu-Lin Du Rongkun Tao Department of Pediatric Cardiology Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Institute of Neuroscience State Key Laboratory of NeuroscienceCenter for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China Medical School Kunming University of Science and TechnologyKunmingYunnan 650500China Scientific Research Center Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China University of Chinese Academy of Sciences Beijing 100049China School of Life Science and Technology ShanghaiTech UniversityShanghai 200031China

Most viruses and transposons serve as effective carriers for the introduction of foreign DNA up to 11 kb into vertebrate ***,their activity markedly diminishes with payloads exceeding 11 *** the payload capacity of transposons could facilitate more sophisticated cargo designs,improving the regulation of expression and minimizing mutagenic risks associated with molecular therapeutics,metabolic engineering,and transgenic animal *** this study,we improved the Tol2 transposon by increasing protein expression levels using a translational enhancer(QBI SP163,ST)and enhanced the nuclear targeting ability using the nuclear localization protein H2B(SHT).The modified Tol2 and ST transposon efficiently integrated large DNA cargos into human cell cultures(H1299),comparable to the well-established super PiggyBac ***,mRNA from ST and SHT showed a significant increase in transgene delivery efficiency of large DNA payloads(8 kb,14 kb,and 24 kb)into zebrafish(Danio rerio).This study presents a modified Tol2 transposon as an enhanced nonviral vector for the delivery of large DNA payloads in transgenic applications.

关键词： Zebrafish Tol2 transposase Transgene Large payload Synthetic biology

Interface optimization of graphene paper-Cu composite prepared by electrodeposition

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Journal of Iron and Steel Research International 2024年第1期31卷 64-73页

作者： Jing Guo Hai-jing wang Shuang-juan Liu peng Zhang Jing-yu Tang Wei-yang Zhang Han-jie Guo peng-cheng wang Cai Meng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Advanced Technology and Materials Co. Ltd.Beijing100083China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei230027AnhuiChina

A room-temperature electrodeposition method with an organic electrolyte was developed to fabricate a HNO3-pretreated graphene paper Cu(GP'-Cu)*** improve the interfacial bonding of GP'-Cu composite,magnetron sputtering technology was used to create a"sandwich"structural gradient GP'-Cu *** selection of the intermediate transition layer metal was based on two-dimensional *** electron microscopy,X-ray photoelectron spectroscopy,and other analytical methods confirmed that the addition of an intermediate transition metal(Cr,Ni)layer reduced the gap distance and enhanced the interfacial bonding of the GP'and Cu deposited *** GP'-Ni-Cu composite exhibited the largest increase in tensile strength and *** addition,it had the highest thermal diffusivity and elongation at break among the GP'-Cu,GP'-Cr-Cu and GP'-Ni-Cu composites.

关键词： Graphene paper Two-dimensional disregistry Magnetron sputtering Metal composite

Algebraic Study of the Vibrational Levels and Potential Energy Surface of the Excited Electronic State （C^1A＇） for S2O

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Chinese Journal of Chemical Physics 2006年第1期19卷 43-46页

作者： Xiao-yan wang Shi-liang Ding Jin-dong Xie peng-cheng wang Wei-gang Zhong Department of RadioloEy Taishan Medical School Taian 271000 China School of Physics and Microelectronics Shandong University ji＇nan 250100 China

The vibrational levels and potential energy surface of a stable structure for S2O in the excited electronic states C^1A＇ were carried out with algebraic method. The vibrational spectra were obtained （with total quantum number v=20） by fitting 30 spectra data. The fitted rms（root mean square） error based on the Hamiltonian witb 9 parameters was 2.40 cm^-1. The dissociation energy and force constant were also determined by the analytical potential energy surface. The method is proved to be effective by comparing these results with the experimental data.

关键词： S2O3 Energy level Potential energy surface

Improved mammalian family phylogeny using gap-rare multiple sequence alignment:A timetree of extant placentals and marsupials

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Zoological Research 2023年第6期44卷 1064-1079页

作者： Gao-Ming Liu Qi Pan Juan Du Ping-Fen Zhu Wei-Qiang Liu Zi-Hao Li Ling wang Chun-Yan Hu Yi-Chen Dai Xiao-Xiao Zhang Zhan Zhang Yang Yu Meng Li peng-cheng wang Xiao wang Ming Li Xu-Ming Zhou Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China School of Life Sciences University of Science and Technology of ChinaHefeiAnhui 230026China College of Life Sciences Nanjing Normal UniversityNanjingJiangsu 210023China

The timing of mammalian diversification in relation to the Cretaceous-Paleogene(KPg)mass extinction continues to be a subject of substantial *** studies have either focused on limited taxonomic samples with available whole-genome data or relied on short sequence alignments coupled with extensive species *** the present study,we improved an existing dataset from the landmark study of Meredith et al.(2011)by filling in missing fragments and further generated another dataset containing 120 taxa and 98 exonic *** these two datasets,we then constructed phylogenies for extant mammalian families,providing improved resolution of many conflicting ***,the timetrees generated,which were calibrated using appropriate molecular clock models and multiple fossil records,indicated that the interordinal diversification of placental mammals initiated before the Late Cretaceous ***,intraordinal diversification of both extant placental and marsupial lineages accelerated after the KPg boundary,supporting the hypothesis that the availability of numerous vacant ecological niches subsequent to the mass extinction event facilitated rapid ***,our results support a scenario of placental radiation characterized by both basal cladogenesis and active interordinal divergences spanning from the Late Cretaceous into the Paleogene.

关键词： Mammals Phylogeny Diversification Evolutionary model

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利用到时差分布图方法进行近场地表震源定位

地球物理学报 2017年第8期60卷 3119-3132页

作者：史鹏程王元游庆瑜中国科学院地质与地球物理研究所油气资源研究重点实验室北京100029 中国科学院大学北京100049

近场震源的高精度定位在工程建设与军事应用等方面意义重大且应用广泛,如炮弹落点定位或车辆追踪等.定位过程面临速度结构未知、高分辨率要求等问题,传统的震源定位方法有一定的局限性.本文将超声波检测中的时差分布图(Delta T Mapping... 详细信息

近场震源的高精度定位在工程建设与军事应用等方面意义重大且应用广泛,如炮弹落点定位或车辆追踪等.定位过程面临速度结构未知、高分辨率要求等问题,传统的震源定位方法有一定的局限性.本文将超声波检测中的时差分布图(Delta T Mapping,简称DTM)方法首次成功引入近场震源定位问题中.DTM定位法首先建立一个测区的到时差模型,然后基于此模型对新的震源进行定位.有两种建立模型的方法,(1)网格搜索法:对原有模型进行线性插值,得到更高分辨率的到时差分布模型;(2)统计定位法:利用高斯过程回归建立到时差数据与位置坐标之间的映射关系.本文在北京某郊区进行了炸点定位实验,在140 m×90 m的测试区域内,定位误差为0.5~5.1 m.结果表明,DTM方法是一种可靠、高精度、具有近实时性的近场震源定位方法.进一步利用接收点、源点互换,在获得高精度DTM同时,可大幅降低标定与数据分析成本.结合震源扫描法具有解决多目标定位问题的潜力.

关键词：震源定位到时差时差分布图法高斯过程回归震源扫描法