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Chemical composition and phytotoxic activity of the volatile oil of invasive Xanthium italicum Moretti from Xinjiang,China

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Journal of Arid Land 2013年第3期5卷 324-330页

作者： Hua SHAO YuanMing ZHANG peng nan XiaoLi HUANG Chi ZHANG Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering School of Life SciencesFudan University State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences

Aerial parts of Xanthium italicum in an air tight container greatly inhibited root elongation of radish, implying that this invasive plant could release biologically active volatile organic compounds （VOCs） into the environment to affect other plants＇ growth. This phenomenon was further studied by evaluating the phytotoxic effects of X. italicum essential oil against two dicot plants, amaranth （Amaranthus mangostanus L.） and lettuce （Lectuca sativa L.）, and two monocot plants, wheat （Triticum aestivum Linn） and ryegrass （Lolium multiforum）, and analyzing the chemical composition of the oil. Among the 4 test species, amaranth was the most sensitive plant, 0.5μl/mL essential oil application resulted in a 50% reduction on root elongation, and 2.5 μl/mL essential oil almost completely inhibited its seedling growth. Wheat was the least sensitive species, whose root growth was reduced to 36% of control by 5 μl/mL essential oil. The essential oil exerted moderate inhibitory effect on both lettuce and ryegrass. Compared to a commercial herbicide-Harness, X. italicum oil exhibited stronger phytotoxicity on amaranth, lettuce and wheat, but weaker activity on ryegrass. The chemical composition of the essential oil isolated by hydrodistillation from the aerial parts of X. italicum Moretti was analyzed by GC/MS. Thirty two compounds were identified, representing 94.89% of total oil, which was found to be rich in monoterpene hydrocarbons （60.71%）. The main constituents of the oil were limonene （51.61%）, germacrene B （6.98%）, 6-cadinol （5.94%）, β-pinene （5.23%）, α-caryophyllene （5.1%） and bornyl acetate （3.15%）. Bioassay revealed the dominant constituent-limonene, was unlikely the responsible phytotoxic compound due to its low biological activity; rather, there might be other oil constituent（s） that either act alone, or work together, and possibly assisted by synergistic effect, to display the phytotoxic activity. Our results suggested that X. italicum might produce allelopathic V

关键词： allelopathy phytotoxicity essential oil volatile organic compounds Xanthium italicum

Stratigraphy and Geochronology of Vertebrate Fossil-Bearing Jurassic Strata from Linglongta,Jianchang County,Western Liaoning,Northeastern China

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Acta Geologica Sinica(English Edition) 2012年第6期86卷 1326-1339页

作者： peng nan LIU Yongqing KUANG Hongwei JIANG Xiaojun XU Huan Institute of Geology Chinese Academy of Geological Sciences School of the Earth Science and Resources China University of Geosciences

Northeastern China contains widely distributed Jurassic terrestrial strata that have yielded many spectacular mammal and pterosaur fossils, in addition to feathered dinosaur fossils and more recent discoveries from Jianchang, particularly from western Liaoning. However, the fossil-bearing stratigraphic succession, regional correlation, and age estimates of the fossils found in Jianchang County and nearby areas have been contentious. Here, we report on the vertebrate fossil-bearing Jurassic stratigraphy from Linglongta, Jianchang County, western Liaoning, including a SHRIMP U-Pb zircon date unambiguously associated with the fossil horizons. The primary goal was to determine the vertebrate fossil-bearing succession. A further aim was to provide age estimations for the fossil-bearing horizon as well as the earliest appearance of feathered dinosaurs, the eutherian-placental clade, and transitional pterosaurs. Field investigations showed that the vertebrate fossil-bearing stratigraphic succession in Jianchang County mainly consists of basal andesites overlain by rhythmic tufts and tuffaceous lacustrine sediments, with the upper intermediate or acidic lavas interbedded with laminated more or less tuffaceous lacustrine deposits. This sequence correlates well with the Middle Jurassic Lanqifl＇iaojishan Formation in northeastern China. Detailed and accurate field observations showed that the well- preserved vertebrate fossils were buried in either the middle or the upper fine-grained laminated lacustrine deposits. Previous and current SHRIMP U-Pb zircon dates provide an age estimation of 161- 159 Myr for the fossil-bearing horizon and vertebrates. This indicates that the earliest appearance of feathered dinosaurs here was more than 159 Myr ago and unquestionably older than Archaeopteryx from Germany, making these the earliest known feathered dinosaurs in the world. Furthermore, the eutherian-placental clade and the known transitional pterosaurs first emerged no later than 161

关键词： Jurassic vertebrates stratigraphy geochronology northeastern China

Genetic technologies for extremely thermophilic microorganisms of Sulfolobus, the only genetically tractable genus of crenarchaea

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Science China(Life Sciences) 2017年第4期60卷 370-385页

作者： nan peng Wenyuan Han Yingjun Li Yunxiang Liang Qunxin She State Key Laboratory of Agricultural Microbiology College of Life Science and Technology Huazhong Agricultural University Archaeal Centre Department of Biology University of Copenhagen

Archaea represents the third domain of life, with the information-processing machineries more closely resembling those of eukaryotes than the machineries of the bacterial counterparts but sharing metabolic pathways with organisms of Bacteria, the sister prokaryotic phylum. Archaeal organisms also possess unique features as revealed by genomics and genome comparisons and by biochemical characterization of prominent enzymes. Nevertheless, diverse genetic tools are required for in vivo experiments to verify these interesting discoveries. Considerable efforts have been devoted to the development of genetic tools for archaea ever since their discovery, and great progress has been made in the creation of archaeal genetic tools in the past decade. Versatile genetic toolboxes are now available for several archaeal models, among which Sulfolobus microorganisms are the only genus representing Crenarchaeota because all the remaining genera are from Euryarchaeota. Nevertheless, genetic tools developed for Sulfolobus are probably the most versatile among all archaeal models, and these include viral and plasmid shuttle vectors, conventional and novel genetic manipulation methods, CRISPR-based gene deletion and mutagenesis, and gene silencing, among which CRISPR tools have been reported only for Sulfolobus thus far. In this review, we summarize recent developments in all these useful genetic tools and discuss their possible application to research into archaeal biology by means of Sulfolobus models.

关键词： plasmid promoter prokaryotic shuttle mutagenesis deletion silencing genomics diverse genera

Numerical simulation of the self-propulsive motion of a fishlike swimming foil using the δ^+-SPH model

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Theoretical & Applied Mechanics Letters 2018年第2期8卷 115-125页

作者： peng-nan Sun Andrea Colagrossi A-Man Zhang College of Shipbuilding Engineering Harbin Engineering University CNR-INSEAN Marine Technology Research Institute

The present work is dedicated to the application of the recently developed （δ＋ -SPH） scheme to the self-propulsive fishlike swimming hydrodynamics. In the numerical method, a particle shifting technique （PST） is implemented in the framework of δ-SPH, combining with an adaptive particle refinement （APR） which is a numerical technique adopted to refine the particle resolution in the local region and de-refine particles outside that region. This comes into being the so-called δ＋- SPH scheme which contributes to higher numerical accuracy and efficiency. In the fishlike swimming modeling, a NACA0012 profile is controlled to perform a wavy motion mimicking the fish swimming in water. Thanks to the mesh-free characteristic of SPH method, the NACA0012 profile can undergo a wavy motion with large amplitude and move forward freely, avoiding the problem of mesh distortion. A parallel staggered algorithm is adopted to perform the fluidstructure interaction between the foil and the surrounding fluid. Two different approaches are adopted for the fishlike swimming problem. In Approach 1, the foil is fixed and flaps in a free stream and in Approach 2, the wavy foil can move forward under the self-driving force. The numerical results clearly demonstrate the capability of the δ＋ -SPH scheme in modeling such kind of self-propulsive fishlike swimming problems.

关键词： Smoothed particle hydrodynamics δ+-SPH Fishlike swinuning Wavy foil Swinuning propulsion

Mesozoic basins and associated palaeogeographic evolution in North China

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Journal of Palaeogeography 2015年第2期4卷 189-202页

作者： Yong-Qing Liu Hong-Wei Kuang nan peng Huan Xu peng Zhang Neng-Sheng Wang Wei An Institute of Geology Chinese Academy of Geological Sciences

In North China, the Mesozoic terrestrial basins, sedimentary palaeogeography and tectonic settings involved five evolutionary stages：（1） the Early-Middle Triassic, （2） the Late Triassic to Early-Middle Jurassic, （3） the Late Jurassic to early Early Cretaceous, （4） the middle-late Early Cretaceous and （5） the Late Cretaceous. The regional punctuated tectonic events occurred during these evolutionary stages. During the Early-Middle Triassic （stage 1）, the Xingmeng Orogenic Belt （XMOB, i.e., east- ern part of Central Asia Orogenic Belt, CAOB） of the northern North China was settled in the transition of tectonic environment from syn-orogenic compression to post-orogenic extension with intensive uplifting. It is a main provenance in the unified Ordos-North China *** united continental plate of China and the Qinling-Dabie-Sulu Orogenic Belt formed due to convergence and collision between the North China Plate and the Yangtze Plate along two suture zones of the Mianlue and the Shangdan in the terminal Middle Triassic. During the Late Triassic to the Early-Middle Jurassic （stage 2）, the Late Triassic mafic or alkaline rocks and intrusions occurred on the northern and southern margins of North China Craton （NCC） and XMOB, implying that intensified extension happened all over the North China （early phase of stage 2）. Additionally, in the late phase of stage 2, the basic volcanic- filing faulted basins were widely distributed in the northeastern North China during the Early- Middle Jurassic, including a series of smalt- to medium-sized basins with coal-bearing strata and some volcanic rocks in other areas of North China, which was the result of subduction of the Palaeo-Pacific Plate during the Early-Middle Jurassic. An active continental margin with accretionary complex developed in the eastern Heilongjiang of China, Japan and the Far East of Russia at that time. However, in the end of the Early-Middle Jurassic, because of the Yan- shanian orogeny characterized by com

关键词： Mesozoic basin orogenic belt tectonic zone palaeogeography North China

Dynamic mechanical behavior of ultra-high strength steel 30CrMnSiNi2A at high strain rates and elevated temperatures

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Journal of Iron and Steel Research International 2017年第7期24卷 724-729页

作者： Qiu-lin Niu Wei-wei Ming Ming Chen Si-wen Tang peng-nan Li College of Mechanical and Electrical Engineering Hunan University of Science and Technology Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material Hunan University of Science and Technology School of Mechanical Engineering Shanghai Jiao Tong University

During high speed machining in the field of manufacture,chip formation is a severe plastic deformation process including large strain,high strain rate and high *** the strain rate in high speed cutting process can be achieved to 105 s^（-1）.30CrMnSiNi2Asteel is a kind of important high-strength low-alloy structural steel with wide application *** the dynamic mechanical properties of30CrMnSiNi2Aunder the conditions of high strain rate and high temperature is necessary to construct the constitutive relation model for high speed *** dynamic compressive mechanical properties of30CrMnSiNi2Asteel were studied using split Hopkinson pressure bar（SHPB）tests at 30-700°C and3000-10000s^（-1）.The stress-strain curves of 30CrMnSiNi2Asteel at different temperatures and strain rates were investigated,and the strain hardening effect and temperature effect were *** results show that 30CrMnSiNi2Ahas obvious temperature sensitivity at 300°***,the flow stress decreased significantly with the increase of *** strain hardening effect of the material at high strain rate is not significant with the increase of *** strain rate hardening effect is obvious with increasing the *** to the experimental results,the established Johnson-Cook（J-C）constitutive model of 30CrMnSiNi2Asteel could be used at high strain rate and high temperature.

关键词： 30CrMnSiNi2A steel Dynamic mechanical behavior Split Hopkinson pressure bar High temperature High strain rate Ultra-high strength steel

CRISPR-Cas-Based Engineering of Probiotics

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BioDesign Research 2023年第1期5卷 121-132页

作者： Ling Liu Shimaa Elsayed Helal nan peng National Key Laboratory of Agricultural Microbiology Hubei Hongshan LaboratoryCollege of Life Science and TechnologyHuazhong Agricultural UniversityWuhan 430070HubeiChina. CABIO Biotech(Wuhan)Co.Ltd. WuhanChina.

Probiotics are the treasure of the microbiology *** have been widely used in the food industry,clinical treatment,and other *** equivocal health-promoting effects and the unknown action mechanism were the largest obstacles for further probiotic’s developed *** recent years,various genome editing techniques have been developed and applied to explore the mechanisms and functional modifications of *** important genome editing tools,CRISPR-Cas systems that have opened new improvements in genome editing dedicated to *** high efficiency,flexibility,and specificity are the advantages of using CRISPR-Cas ***,we summarize the classification and distribution of CRISPR-Cas systems in probiotics,as well as the editing tools developed on the basis of ***,we discuss the genome editing of probiotics based on CRISPR-Cas systems and the applications of the engineered probiotics through CRISPR-Cas ***,we proposed a design route for CRISPR systems that related to the genetically engineered probiotics.

关键词： CRISPR editing distribution

Detecting putative recombination events of hepatitis B virus: An updated comparative genome analysis

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Chinese Science Bulletin 2010年第22期55卷 2373-2379页

作者： YE Lin ZHANG Yuan MEI Yi nan peng ZHONG Yang Center for Evolutionary Biology School of Life Sciences Fudan University Shanghai 200433 China Institute of Pathogen Biology Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100730 China Shanghai Center for Bioinformation Technology Shanghai 200235 China Institute of Biodiversity Science and Geobiology Tibet University Lhasa 850000 China

An updated collection of 791 human hepatitis B virus (HBV) genomes and 38 non-human primate HBV genomes was analyzed for identifying putative recombination events and their recombinants by using two bioinformatics software tools: Simplot and RDP3 with five algorithms (RDP, GENECONV, MaxChi, Chimaera, and SiScan). A total of 61 recombinants from nine putative recombination events were detected with RDP3, especially the breakpoints of six events which have both two parental sequences that can be determined precisely with Simplot. To our knowledge, 53 recombinants were found for the first time. Our study also suggests that a relatively high recombination frequency occurs in the PreC/C gene region and the position near gene boundaries.

关键词：基因组分析乙肝病毒重组体事件检测乙型肝炎病毒生物信息学灵长目动物

Numerical study of the splashing wave induced by a seaplane using mesh-based and particle-based methods

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Theoretical & Applied Mechanics Letters 2023年第5期13卷 375-381页

作者： Yang Xu peng-nan Sun Xiao-Ting Huang Salvatore Marrone Lei-Ming Geng School of Ocean Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China CNR-INM.Institute of Marine Engineering Rome 00128Italy AVIC General Huanan Aircraft Industry Co. LtdZhuhai 519080China

In recent years,forest fires and maritime accidents have occurred frequently,which have had a bad impact on human production and ***,the development of seaplanes is an increasingly urgent *** is important to study the taxiing process of seaplanes for the development of seaplanes,which is a strong nonlinear fluid-structure interaction *** this paper,the smoothed particle hydrodynamics(SPH)method based on the Lagrangian framework is utilized to simulate the taxiing process of seaplanes,and the SPH results are compared with those of the finite volume method(FVM)based on the Eulerian *** results show that the SPH method can not only give the same accuracy as the FVM but also have a strong ability to capture the splashing waves in the taxiing process,which is quite meaningful for the subsequent study of the effect of a splash on other parts of the seaplane.

关键词： Seaplane Splashing Fluid-structure interactions SPH Method