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Chromosome-scale genome assembly of marigold (Tagetes erecta L.):An ornamental plant and feedstock for industrial lutein production

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Horticultural Plant Journal 2023年第6期9卷 1119-1130页

作者： Haibo Xin Fangfang Ji Jie Wu Shiya zhang Caijie Yi Shiwei zhao Richen Cong Liangjun zhao Hua zhang zhao zhang Beijing Key Laboratory of Greening Plants Breeding Beijing Academy of Forestry and Landscape ArchitectureBeijing 100102China Beijing Key Laboratory of Development and Quality Control of Ornamental Crops Department of Ornamental HorticultureChina Agricultural UniversityBeijing 100193China

Marigold(Tagetes erecta L., African marigold) is a widely grown ornamental plant and a main source of the carotenoid lutein for the industrial production of pharmaceuticals, food coloring, and feed additives. To gain a deeper understanding of the genetic mechanism of lutein in marigold, a chromosome-scale assembly of the marigold(T. erecta V-01) genome was completed based on Illumina, PacBio, and Hi-C reads. The707.21-Mb assembled genome consisted of 35 834 annotated protein-coding genes, with 97.7% genomic integrity. We anchored 87.8% of the contigs(covering 621.20 Mb) to 12 pseudochromosomes, bringing the scaffold N50 length to 54.15 Mb. Phylogenetic analysis showed that marigold was closely related to the Asteraceae species bitter vine(Mikania micrantha) and sunflower(Helianthus annuus), all three of which originated in the Americas. Marigold diverged from the sunflower clade 23.57 million years ago(MYA) and from M. micrantha 19.59 *** has undergone three whole-genome duplication events, as well as a recent whole-genome duplication event(WGD-2) common to *** and M. micrantha. Marigold gene families were significantly less expanded than those of M. micrantha or H. annuus, and the marigold genome contained significantly fewer interspersed repeats, which might account for its smaller genome. In addition, a range of candidate genes involved in the lutein biosynthetic pathway were identified. The high-quality reference genome obtained in this study provided a valuable genomic resource for studying the evolution of the Asteraceae family and for improving marigold breeding strategies.

关键词： T.erecta L. Genome Gene family Carotenoid Lutein

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Single-chain and monolayered conjugated polymers for molecular electronics

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Chinese Chemical Letters 2016年第8期27卷 1209-1222,1466页

作者： zhao-Yang zhang Tao Li School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China

Exploring the charge transport properties and electronic functions of molecules is of primary interest in the area of molecular *** polymers（CPs） represent an attractive class of molecular candidates,benefiting from their outstanding optoelectronic ***,they have been less studied compared with the small-molecule family,mainly due to the difficulties in incorporating CPs into molecular *** this review,we present a summary on how to fabricate CP-based singlechain and monolayered junctions,then discuss the transport behaviors of CPs in different junction architectures and finally introduce the potential applications of CPs in molecular-scale electronic *** the research on CP-based molecular electronics is still at the initial stage,it is widely accepted that（1） CP chains are able to mediate long-range charge transport if their molecular electronic structures are properly designed,which makes them potential molecular wires,and（2） the intrinsic optoelectronic properties of CPs and the possibility of incorporating desirable functionalities by synthetic strategies imply the potential of employing tailor-made polymeric components as alternatives to small molecules for future molecular-scale electronics.

关键词： Molecular electronics Conjugated polymers Molecular junctions Charge transport Molecular wire Functional devices

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Qualitative Analysis and Solutions of Bounded Traveling Wave for B-BBM Equation

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Acta Mathematicae Applicatae Sinica 2010年第3期26卷 415-426页

作者： Yan zhao Wei-guo zhang School of Science University of Shanghai for Science and Technology Shanghai 200093 China

In this paper, we apply the theory of planar dynamical systems to carry out qualitative analysis for the dynamical system corresponding to B-BBM equation, and obtain global phase portraits under various parameter conditions. Then, the relations between the behaviors of bounded traveling wave solutions and the dissipation coeffiicient μ are investigated. We find that a bounded traveling wave solution appears as a kink profile solitary wave solution when μ is more than the critical value obtained in this paper, while a bounded traveling wave solution appears as a damped oscillatory solution when μ is less than it. Furthermore, we explain the solitary wave solutions obtained in previous literature, and point out their positions in global phase portraits. In the meantime, approximate damped oscillatory solutions are given by means of undetermined coefficients method. Finally, based on integral equations that reflect the relations between the approximate damped oscillatory solutions and the implicit exact damped oscillatory solutions, error estimates for the approximate solutions are presented.

关键词： B-BBM equation qualitative analysis global phase portrait solitary wave solution,damped oscillatory solution

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硅烷改性钛石膏沥青胶浆性能研究

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森林工程 2025年第1期41卷 185-194页

作者：董营营苏纪壮张朝魏毛元张惠勤王凯山东高速集团四川乐宜公路有限公司成都610041 山东高速工程检测有限公司济南250002 大宗固废材料在交通领域行业循环利用行业研发中心济南250002

为降低钛石膏堆积带来的环境问题,同时缓解道路材料短缺现状,采用钛石膏和硅烷偶联剂处理后的钛石膏部分或全部代替石灰岩矿粉,研究钛石膏和改性钛石膏对沥青胶浆常规性能和流变性能的影响。首先通过激光粒度仪和扫描电子显微镜分析钛... 详细信息

为降低钛石膏堆积带来的环境问题,同时缓解道路材料短缺现状,采用钛石膏和硅烷偶联剂处理后的钛石膏部分或全部代替石灰岩矿粉,研究钛石膏和改性钛石膏对沥青胶浆常规性能和流变性能的影响。首先通过激光粒度仪和扫描电子显微镜分析钛石膏、改性钛石膏和石灰岩矿粉的粒度分布情况及微观形貌。然后制备不同钛石膏和改性钛石膏掺量的沥青胶浆,采用常规试验方法、温度扫描试验、频率扫描试验、多重应力蠕变恢复(mutiple stress creep recovery,MSCR)试验、线性振幅扫描(linear amplitude sweep,LAS)试验和弯曲梁流变(bending beam rheometer,BBR)试验测试沥青胶浆的三大指标(针入度、延度和软化点)、高温流变性能、抗疲劳性能和低温流变性能。结果表明,钛石膏和改性钛石膏的粒度范围更广,表面更为粗糙;钛石膏和改性钛石膏的加入降低了沥青胶浆的延度、针入度、不可恢复蠕变柔量(Jnr)、疲劳寿命(N_(f))、蠕变速率(m)和相位角(δ),软化点、复数模量(G^(*))、弹性恢复率(R)和蠕变劲度模量(S)有所提高,即高温性能有所提高,低温性能和疲劳性能有所下降。相同温度下,改性钛石膏的高温性能和弹性恢复指标要优于钛石膏,低温性能有所降低。研究证实使用钛石膏进行沥青混合料生产的可行性,为钛石膏的资源化利用开拓方向。

关键词：钛石膏沥青胶浆改性钛石膏矿粉流变性能

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Multiple-pole solutions and degeneration of breather solutions to the focusing nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2022年第4期74卷 13-22页

作者： zhao zhang Junchao Chen Qi Guo Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices South China Normal UniversityGuangzhou 510631China Department of Mathematics and Institute of Nonlinear Analysis Lishui UniversityLishui 323000China

Based on the Hirota’s method,the multiple-pole solutions of the focusing Schr?dinger equation are derived directly by introducing some new ingenious limit *** have carefully investigated these multi-pole solutions from three perspectives:rigorous mathematical expressions,vivid images,and asymptotic ***,there are two kinds of interactions between multiple-pole solutions:when two multiple-pole solutions have different velocities,they will collide for a short time;when two multiple-pole solutions have very close velocities,a long time coupling will *** last important point is that this method of obtaining multiple-pole solutions can also be used to derive the degeneration of N-breather *** method mentioned in this paper can be extended to the derivative Schr?dinger equation,Sine-Gorden equation,mKdV equation and so on.

关键词： multiple-pole solutions degenerate solutions Hirota’s bilinear method

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Structure and function of neuropeptide F in insects

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Journal of Integrative Agriculture 2020年第6期19卷 1429-1438页

作者： CUI Hong-ying zhao zhang-wu Department of Entomology/MOA Key Lab of Pest Monitoring and Green Management College of Plant ProtectionChina Agricultural UniversityBeijing 100193P.R.China

In sect n europeptides are a group of brain n euro-regulatory factors,which plays very important roles in growth and developme nt,molting and metamorphosis,as well as mating and *** neuropeptide F(NPF),a multi-functional neuropeptide,is one of neuropeptides identified in numerous insect species,which plays important roles in feeding,metabolism,courtship,reproduction,aggression,ethanol sensitivity,locomotor circadian rhythms,learning and stress *** roles of NPF are implemented through NPF receptors(NPFR).The NPFR1,a G protein-coupled receptor with 7 transmembrane domai ns,is one of these receptors and is found to be imports nt for NPF *** NPF usually is con sisted of around 36-40 amino acid residues,but the short neuropeptide F(sNPF)consisted of 7-16 amino acid residues have also been found in some *** this review,the structure and function of both NPF and sNPF in in sects are discussed.

关键词： neuropeptide NPF sNPF NPFR1 insects

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The comparative analysis of rocks' resistance to forward-slanting disc cutters and traditionally installed disc cutters

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Acta Mechanica Sinica 2016年第4期32卷 690-695页

作者： zhao-Huang zhang Sun Fei Meng Liang School of Energy Power and Mechanical EngineeringNorth China Electric Power University School of Foreign Languages North China Electric Power University

At present, disc cutters of a full face rock tunnel boring machine are mostly mounted in the traditional way. Practical use in engineering projects reveals that this installation method not only heavily affects the operation life of disc cutters, but also increases the energy consumption of a full face rock tunnel boring machine. To straighten out this issue, therefore, a rock-breaking model is developed for disc cutters＇ movement after the research on the rock breaking of forward-slanting disc cutters. Equations of its displacement are established based on the analysis of velocity vector of a disc cutter＇s rock-breaking point. The functional relations then are brought forward between the displacement parameters of a rock-breaking point and its coordinate through the analysis of micro displacement of a rock-breaking point. Thus, the geometric equations of rock deformation are derived for the forward-slanting installation of disc cutters. With a linear relationship remaining between the acting force and its deformation either before or after the leap breaking, the constitutive relation of rock deformation can be expressed in the form of generalized Hooke law, hence the comparative analysis of the variation in the resistance of rock to the disc cutters mounted in the forward-slanting way with that in the traditional way. It is discovered that with the same penetration, strain of the rock in contact with forwardslanting disc cutters is apparently on the decline, in otherwords, the resistance of rock to disc cutters is reduced. Thus wear of disc cutters resulted from friction is lowered and energy consumption is correspondingly decreased. It will be useful for the development of installation and design theory of disc cutters, and significant for the breakthrough in the design of full face rock tunnel boring machine.

关键词： installed breaking installation rock apparently tunnel traditionally decline remaining brought

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Rock deformation equations and application to the study on slantingly installed disc cutter

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Acta Mechanica Sinica 2014年第4期30卷 540-546页

作者： zhao-Huang zhang Liang Meng Fei Sun School of Energy Power and Mechanical EngineeringNorth China Electric Power University School of Foreign Languages North China Electric Power University

At present the mechanical model of the interac- tion between a disc cutter and rock mainly concerns indentation experiment, linear cutting experiment and tunnel boring machine （TBM） on-site data. This is not in line with the actual rock-breaking movement of the disc cutter and impedes to some extent the research on the rock-breaking mechanism, wear mechanism and design theory. Therefore, our study focuses on the interaction between the slantingly installed disc cutter and rock, developing a model in accordance with the actual rock-breaking movement. Displacement equations are established through an analysis of the velocity vector at the rock-breaking point of the disc cutter blade; the func- tional relationship between the displacement parameters at the rock-breaking point and its rectangular coordinates is established through an analysis of micro-displacement vectors at the rock-breaking point, thus leading to the geometric equations of rock deformation caused by the slantingly installed disc cutter. Considering the basically linear relationship between the cutting force of disc cutters and the rock deformation before and after the leap break of rock, we express the constitutive relations of rock deformation as generalized Hooke＇s law and analyze the effect of the slanting installa- tion angle of disc cutters on the rock-breaking force. This will, as we hope, make groundbreaking contributions to the development of the design theory and installation practice of TBM.

关键词： TBM Disc cutter· Geometric equation Slant-ingly installed Rock-breaking

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Frontiers of Information Technology & Electronic Engineering 2016年第3期17卷 212-223页

作者： Xiao-hu MA Meng YANG zhao zhang School of Computer Science and Technology Soochow University State Key Laboratory for Novel Software Technology Nanjing University

The feature extraction algorithm plays an important role in face recognition. However, the extracted features also have overlapping discriminant information. A property of the statistical uncorrelated criterion is that it eliminates the redundancy among the extracted discriminant features, while many algorithms generally ignore this property. In this paper, we introduce a novel feature extraction method called local uncorrelated local discriminant embedding(LULDE). The proposed approach can be seen as an extension of a local discriminant embedding(LDE)framework in three ways. First, a new local statistical uncorrelated criterion is proposed, which effectively captures the local information of interclass and intraclass. Second, we reconstruct the affinity matrices of an intrinsic graph and a penalty graph, which are mentioned in LDE to enhance the discriminant property. Finally, it overcomes the small-sample-size problem without using principal component analysis to preprocess the original data, which avoids losing some discriminant information. Experimental results on Yale, ORL, Extended Yale B, and FERET databases demonstrate that LULDE outperforms LDE and other representative uncorrelated feature extraction methods.

关键词： Feature extraction Local discriminant embedding Local uncorrelated criterion Face recognition

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Shale gas reservoir characteristics of Ordovician-Silurian formations in the central Yangtze area, China

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Frontiers of Earth Science 2017年第1期11卷 184-201页

作者： Chang'an SHAN Tingshan zhang Yong WEI zhao zhang School of Earth Sciences and Engineering Xi'an Shiyou University Xi'an 710065 China State Key Laboratory of Oil and Gas Reservoir Geology and Exploration Southwest Petroleum University Chengdu 610500 China School of Geoscience and Technology Southwest Petroleum University Chengdu 610500 China Exploration and Development Research Institute Southwest Oil & Gas field Company CNPC Chengdu 610041 China Exploration and Development department Zhejiang Oilfield Company CNPC Hangzhou 310023 China

The characteristics of a shale gas reservoir and the potential of a shale gas resource of Ordovician-Silurian age in the north of the central Yangtze area were determined. Core samples from three wells in the study area were subjected to thin-section examination, scanning electron microscopy, nuclear magnetic resonance testing, X-ray diffraction mineral analysis, total organic carbon （TOC） testing, maturity testing, gas-bearing analysis, and gas component and isothermal adsorption experiments. A favorable segment of the gas shale reservoir was found in both the Wufeng Formation and the lower part of the Longmaxi Formation; these formations were formed from the late Katian to early Rhuddanian. The high-quality shale layers in wells J1, J2, and J3 featured thicknesses of 54.88 m, 48.49 m, and 52.00 m, respectively, and mainly comprised carbonaceous and siliceous shales. Clay and brittle minerals showed average contents of 37.5% and 62.5% （48.9% quartz）, respectively. The shale exhibited type Ⅱ1 kerogens with a vitrinite reflectance ranging from 1.94% to 3.51%. TOC contents of 0.22%-6.05% （average, 2.39%） were also observed. The reservoir spaces mainly included micropores and microfractures and were characterized by low porosity and permeability. Well J3 showed generally high gas contents, i.e., 1.12-3.16 m^3/t （average 2.15 m^3/t）, and its gas was primarily methane. The relatively thick black shale reservoir featured high TOC content, high organic material maturity, high brittle mineral content, high gas content, low porosity, and low permeability. Shale gas adsorption was positively correlated with TOC content and organic maturity, weakly positive correlated with quartz content, and weakly negatively correlated with clay content. Therefore, the Wufeng and Longmaxi formations in the north of the central Yangtze area have a good potential for shale gas exploration.

关键词： reservoir characteristic shale gas Upper Ordovician Lower Silurian central Yangtze area

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