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Population Genetic Structure of the Medicinal Plant Vitex rotundifolia in China: Implications for its Use and Conservation

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Journal of Integrative Plant Biology 2008年第9期50卷 1118-1129页

作者： Yuan Hu Yu Zhu Qiao-Yan Zhang hai-liang Xin lu-Ping Qin Bao-Rong lu Khalid Rahman Han-Chen Zheng Department of Pharmacognosy School of Pharmacy Second Military Medical University Shanghai 200433 China Chinese People's Liberation Army General Hospital Beijing 100853 China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Department of Ecology and Evolutionary Biology Fudan University Shanghai 200433 China Faculty of Science School of Biomolecular Sciences Liverpool John Moores University Liverpool L3 3AF England UK

Vitex rotundifolia L. is an important plant species used in traditional Chinese medicine. For its efficient use and conservation, genetic diversity and clonal variation of V. rotundifolia populations in China were investigated using inter-simple sequence repeat markers. Fourteen natural populations were included to estimate genetic diversity, and a large population with 135 individuals was used to analyze clonal variation and fine-scale spatial genetic structure. The overall genetic diversity （GD） of V. rotundifolia populations in China was moderate （GD=0.190）, with about 40% within-population variation. Across all populations surveyed, the average within-population diversity was moderate （P = 22.6%; GD = 0.086）. A relatively high genetic differentiation （Gst = 0.587） among populations was detected based on the analysis of molecular variance data. Such characteristics of V. rotundifofia are likely attributed to its sexual/asexual reproduction and limited gene flow. The genotypic diversity （D = 0.992） was greater than the average values of a clonal plant, indicating its significant reproduction through seedlings. Spatial autocorrelation analysis showed a clear within-population structure with gene clusters of approximately 20 m. Genetic diversity patterns of V. rotundifolia in China provide a useful guide for its efficient use and conservation by selecting particular populations displaying greater variation that may contain required medicinal compounds, and by sampling individuals in a population at 〉20 m spatial intervals to avoid collecting individuals with identical or similar genotypes.

关键词： beach vitex medicinal plant conservation Vitex rotundifolia gene cluster genetic diversity sampling strategy spatial structure.

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Factors Affecting Polymer Translocation Through a Nanopore in a Membrane

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Chinese Journal of Chemical Physics 2008年第3期21卷 275-280页

作者： Tao Chen Teng lu Hao-iun liang Hefei National Laboratory for Physical Sciences at Microscale Department of Polymer Science andEnEineerinE University of Science and Technology of China Hefei 230025 China

Monte Carlo simulations were used to study the translocation of a flexible polymer through a pore in a membrane, assuming an attractive interaction between the monomers and the membrane on the trans side of the membrane and no interaction on the cis side. For the case T〈Tc （the temperature corresponding to the minimum in the translocation time τ）, the value of τdecreases with increasing temperature, whereas for T〉Tc, τ increases with increasing temperature. The translocation time depends on the absorbed energy uo in a nontrivial way. The value of τ increases initially upon increasing uo before it begins to decrease. The variation of the translocation time with respect to the solvent quality was also studied. It showed that there is a transition, as the solvent quality improves from ＂poor＂ to ＂good＂： when εAB〈εc （the interaction energy corresponding to the minimum in τ）, τdecreases with increasing the value of εAB; when εAB〉εc, τincreases with increasing εAB- When the chain length was changed, it was found that when the absorbed energy uo was greater than uc,τ was proportional to N1.602; for uo〈uc, τ∝N2.248. As the solvent quality improved from ＂poor＂ to ＂good,＂ the translocation probability increased initially before becoming stable.

关键词： Monte Carlo simulation Translocation time Absorbed energy Solvent quality

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Evaluation of global land cover maps for cropland area estimation in the conterminous United States

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International Journal of Digital Earth 2015年第2期8卷 102-117页

作者： lu liang Peng Gong Department of Environmental Science Policy and ManagementUniversity of CaliforniaBerkeleyCAUSA Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System ScienceTsinghua UniversityBeijingChina

Global land cover data could provide continuously updated cropland acreage and distribution information,which is essential to a wide range of applications over large geographical *** area estimates were evaluated in the conterminous USA from four recent global land cover products:MODIS land cover(MODISLC)at 500-m resolution in 2010,GlobCover at 300-m resolution in 2009,FROM-GLC and FROM-GLC-agg at 30-m resolution based on Landsat imagery circa 2010 against the US Department of Agriculture survey *** estimators derived from the 30-m resolution Cropland Data Layer were applied to MODIS and GlobCover land cover products,which greatly improved the estimation accuracy of MODISLC by enhancing the correlation and decreasing mean deviation(MDev)and RMSE,but were less effective on GlobCover *** found that,in the USA,the CDL adjusted MODISLC was more suitable for applications that concern about the aggregated county cropland acreage,while FROM-GLC-agg gave the least deviation from the survey at the state *** between land cover map estimates and survey estimates is significant,but stronger at the state level than at the county *** regions where most mismatches happen at the county level,MODIS tends to underestimate,whereas MERIS and Landsat images incline to *** uncertainties should be taken into consideration in relevant *** interannual and seasonal effects,R 2 of the FROM-GLC regression model increased from 0.1 to 0.4,and the slope is much closer to *** analysis shows that images acquired in growing season are most suitable for Landsat-based cropland mapping in the conterminous USA.

关键词： cropland area global land cover FROM-GLC area estimation NASS survey

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Effect of stochastic electromagnetic disturbances on autapse neuronal systems

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Chinese Physics B 2018年第11期27卷 349-357页

作者： liang-Hui Qu Lin Du Zi-Chen Deng Zi-lu Cao hai-Wei Hu School of Natural and Applied Sciences Northwestern Polytechnical University Xi＇an 710129 China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi ＇ an 710129 China College of Science Zhongyuan University of Technology Zhengzhou 450007 China

With the help of a magnetic flux variable, the effects of stochastic electromagnetic disturbances on autapse Hodgkin–Huxley neuronal systems are studied systematically. Firstly, owing to the autaptic function, the inter-spike interval series of an autapse neuron not only bifurcates, but also presents a quasi-periodic characteristic. Secondly, an irregular mixed-mode oscillation induced by a specific electromagnetic disturbance is analyzed using the coefficient of variation of inter-spike intervals. It is shown that the neuronal discharge activity has certain selectivity to the noise intensity, and the appropriate noise intensity can induce the significant mixed-mode oscillations. Finally, the modulation effects of electromagnetic disturbances on a ring field-coupled neuronal network with autaptic structures are explored quantitatively using the average spiking frequency and the average coefficient of variation. The electromagnetic disturbances can not only destroy the continuous and synchronous discharge state, but also induce the resting neurons to generate the intermittent discharge mode and realize the transmission of neural signals in the neuronal network. The studies can provide some theoretical guidance for applying electromagnetic disturbances to effectively control the propagation of neural signals and treat mental illness.

关键词： neuronal system electromagnetic disturbance autapse mixed-mode oscillations

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Quantum transport in topological semimetals under magnetic fields

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Frontiers of physics 2017年第3期12卷 43-60页

作者： hai-Zhou lu Shun-Qing Shen Department of Physics The University of Hong Kong Pokfulam Road Hong Kong China

Topological semimetals are three-dimensional topological states of matter, in which the conduction and valence bands touch at a finite number of points, i.e., the Weyl nodes. Topological semimetals host paired monopoles and antimonopoles of Berry curvature at the Weyl nodes and topologically protected Fermi arcs at certain surfaces. We review our recent works on quantum transport in topo- logical semimetals, according to the strength of the magnetic field. At weak magnetic fields, there are competitions between the positive magnetoresistivity induced by the weak anti-localization effect and negative magnetoresistivity related to the nontrivial Berry curvature. We propose a fitting formula for the magnetoconductivity of the weak anti-localization. We expect that the weak localization may be induced by inter-valley effects and interaction effect, and occur in double-Weyl semimetals. For the negative magnetoresistance induced by the nontrivial Berry curvature in topological semimetals, we show the dependence of the negative magnetoresistance on the carrier density. At strong magnetic fields, specifically, in the quantum limit, the magnetoconductivity depends on the type and range of the scattering potential of disorder. The high-field positive magnetoconductivity nmy not be a com- pelling signature of the chiral anomaly. For long-range Gaussian scattering potential and half filling, the magnetoconductivity can be linear in the quantum limit. A minimal conductivity is found at the Weyl nodes although the density of states vanishes there.

关键词： topological semimetal magnetoconductivity magnetoresistance localization,anti-localization chiral anomaly

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Online Scheduling on a Parallel Batch Machine with Delivery Times and Limited Restarts

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Journal of the Operations Research Society of China 2022年第1期10卷 113-131页

作者： hai-Ling Liu Xi-Wen lu Department of Mathematics East China University of Science and TechnologyShanghai 200237China College of Science Henan University of EngineeringZhengzhou 451191HenanChina

The online scheduling on an unbounded parallel batch machine with delivery times and limited restarts is studied in this ***,online means that jobs arrive over time and the characteristics of a job become known until it *** restarts mean that once a running batch contains at least one restarted job,it cannot be restarted *** goal is to minimize the time by which all jobs have been *** consider a restricted model that the delivery time of each job is no more than its processing *** present a best possible online algorithm with a competitive ratio of 3/2 for the problem.

关键词： Online scheduling Parallel batch Limited restart Delivery time

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Sedimentary Records of Heavy Metal Pollution in Fuxian Lake,Yunnan Province,China:Intensity,History,and Sources

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Pedosphere 2009年第5期19卷 562-569页

作者： ZENG hai-Ao WU Jing-lu State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences 73 East Beijing Road Nanjing 210008 (China) Graduate University of the Chinese Academy of Sciences Beijing 100049 (China)

This study focused on the concentration change of heavy metals of sediment cores in heavily polluted north area and less polluted middle area of Fuxian Lake in Southwest *** the basis of the analysis of Cu,Ni,Ti,V,Pb,Cd,and Zn concentration-depth profiles,the pollution history of heavy metals was studied using 137cesium(137Cs) *** sources of heavy metals were distinguished by normalization of their profiles to aluminum and analysis of heavy metal concentrations of potential source *** index(Igeo) was used to quantify their contamination *** results showed that all the heavy metals found in the Fuxian Lake sediments originated naturally before ***,Ni,Ti,and V were still mainly natural in the north lake after 1980s,Cu,Ni,Ti,V,and Pb were mainly natural in the middle lake at all time,but the concentrations of Pb and Zn in the north lake were influenced by industrial wastes from the phosphorus fertilizer factory and cement *** all the lake,the contaminations of Cd and Zn were the results of agricultural cultivation using a large amount of fertilizers and the atmospheric fallouts of dusts from cement *** present,the geoaccumulation indices showed that the Fuxian Lake sediments were moderately to strongly polluted by Cd in the middle lake,and unpolluted to moderately polluted by Pb and Zn and strongly polluted by Cd in the north ***,the pollution intensities of Cd,Zn,and Pb have been increased since 1980s.

关键词： agricultural fertilizers geoaccumulation index industrial wastes lake sediments sediment cores

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Exact Solutions to (2+1)-Dimensional Kaup-Kupershmidt Equation

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Communications in Theoretical Physics 2009年第11期52卷 795-800页

作者： lu hai-Lin LIU Xi-Qiang School of Mathematical Sciences Liaocheng University Liaocheng 252059 China

In this paper, by using the symmetry method, the relationships between new explicit solutions and old ones of the （2＋1）-dimensional Kaup-Kupershmidt （KK） equation are presented. We successfully obtain more general exact travelling wave solutions for （2＋ 1）-dimensional KK equation by the symmetry method and the （G1/G）-expansion method. Consequently, we find some new solutions of （2＋1）-dimensional KK equation, including similarity solutions, solitary wave solutions, and periodic solutions.

关键词： (2+1)-dimensional Kaup-Kupershmidt equation the symmetry method the (G1/G)-expansion method exact solutions

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Prime in Quadratic Progressions on Average

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Acta Mathematica Sinica,English Series 2011年第6期27卷 1187-1194页

作者： Guang Shi lu hai Wei SUN Department of Mathematics Shandong University Ji'nan 250100 P. R. China

In this paper we study the distribution of primes in quadratic progressions on average. Our result improves a previous result of Baier and Zhao in some aspects.

关键词： Primes quadratic progressions circle method

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Flux and spectral variation characteristics of 3C 454.3 at the GeV band

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Research in Astronomy and Astrophysics 2018年第4期18卷 23-42页

作者： hai-Ming Zhang Jin Zhang Rui-Jing lu Ting-Feng Yi Xiao-Li Huang En-Wei liang Guangxi Key Laboratory for Relativistic Astrophysics Department of Physics Guangxi University Key Laboratory of Space Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences Department of Physics Yunnan Normal University

We analyze the long-term lightcurve of 3C 454.3 observed with Fermi/LAT and investigate its relation to flux in the radio,optical and X-ray *** fitting the 1-day binned Ge V lightcurve with multiple Gaussian functions（MGF）,we propose that the typical variability timescale in the Ge V band is 1–10 *** Ge V flux variation is accompanied by the spectral variation characterized as fluxtracking,i.e.,＂harder when brighter.＂The Ge V flux is correlated with the optical and X-ray fluxes,and a weak correlation betweenγ-ray flux and radio flux is also ***γ-ray flux is not correlated with the optical linear polarization degree for the global lightcurves,but they show a correlation for the lightcurves before MJD *** power density spectrum of the global lightcurve shows an obvious turnover at^7.7 d,which may indicate a typical variability timescale of 3C 454.3 in theγ-ray *** is also consistent with the derived timescales by fitting the global lightcurve with *** spectral evolution and an increase in the optical linear polarization degree along with the increase inγ-ray flux may indicate that the radiation particles are accelerated and the magnetic field is ordered by the shock processes during the *** addition,the nature of 3C 454.3 may be consistent with a self-organized criticality system,similar to Sagittariusand thus the outbursts could be from plasmoid ejections driven by magnetic *** may further support the idea that the jet radiation regions are magnetized.

关键词： gamma rays galaxies — galaxies jets — quasars individual(3C 454.3)

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