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Variable stars in the field of open cluster NGC 2126

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Research in Astronomy and Astrophysics 2009年第7期9卷 791-802页

作者： shun-Fang Liu Zhen-Yu Wu Xiao-Bin Zhang jiang-Hua Wu jun Ma Zhao-ji jiang jian-Sheng Chen Xu Zhou National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We report the results of a time-series CCD photometric survey of variable stars in the field of open cluster NGC 2126. In about a one square degree field covering the cluster, a total of 21 variable candidates are detected during this survey, of which 16 are newly found. The periods, classifications and spectral types of 14 newly discovered variables are discussed, which consist of six eclipsing binary systems, three pulsating variable stars, three long period variables, one RS CVn star, and one W UMa or δ Scuff star. In addition, there are two variable candidates, the properties of which cannot be determined. By a method based on fitting observed spectral energy distributions of stars with theoretical ones, the membership probabilities and the fundamental parameters of this cluster are determined. As a result, five variables are probably members of NGC 2126. The fundamental parameters of this cluster are determined as： metallicity to be 0.008 Z, age log（t） = 8.95, distance modulus （m - M）0 = 10.34 and reddening value E（B - V） = 0.55 mag.

关键词： open clusters: individual (NGC 2126) - stars: variables (general) - bina- ties: general

Receptor variability-driven evolution of snake toxins

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Zoological Research 2018年第6期39卷 431-436页

作者： Xian-Hong ji Shang-Fei Zhang Bin Gao shun-Yi Zhu Group of Peptide Biology and Evolution State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Three-finger toxins （TFTs） are well-recognized non- enzymatic venom proteins found in snakes. However, although TFTs exhibit accelerated evolution, the drivers of this evolution remain poorly understood. The structural complexes between long-chain α-neurotoxins, a subfamily of TFTs, and their nicotinic acetylcholine receptor targets have been determined in previous research, providing an opportunity to address such questions. In the current study, we observed several previously identified positively selected sites （PSSs） and the highly variable C-terminal loop of these toxins at the toxin/receptor interface. Of interest, analysis of the molecular adaptation of the toxin-recognition regions in the corresponding receptors provided no statistical evidence for positive selection. However, these regions accumulated abundant amino acid variations in the receptors from the prey of snakes, suggesting that accelerated substitution of TFTs could be a consequence of adaptation to these variations. To the best of our knowledge, this atypical evolution, initially discovered in scorpions, is reported in snake toxins for the first time and may be applicable for the evolution of toxins from other venomous animals.

关键词： Three-finger toxins Nicotinic acetylcholine receptor Driver

Identification of main effect and epistatic QTLs controlling initial flowering date in cultivated peanut(Arachis hypogaea L.)

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Journal of Integrative Agriculture 2020年第10期19卷 2383-2393页

作者： WANG Liang YANG Xin-lei CUI shun-li WANG ji-hong HOU Ming-yu MU Guo-jun LI Zi-chao LIU Li-feng College of Agronomy Hebei Agricultural University/North China Key Laboratory for Crop Germplasm ResourcesMinistry of Education/State Key Laboratory of North China Crop Improvement and RegulationBaoding 071001P.R.China College of Agronomy and Biotechnology China Agricultural University/Key Laboratory of Crop Heterosis and Utiliz ationMinistry of Education/Bejing Key Laboratory of Crop Genetic IlmprovementBejing 100193P.R.China Crop Research Institute Xinjiang Academy of Agricultural and Reclamation SciencesShihezi 832000P.R.China School of Statistics University of International Business and EconomicsBejing 100029P.R.China College of Science Shihezi UniversityShihezi 832003P.R.China

Initial flowering date(IFD)is closely related to mature period of peanut *** present study,a population of recombinant inbred lines(RIL)derived from the cross between Silihong(female parent)and jinonghei 3(male parent)was used to map QTLs associated with *** RIL population and its two parental cultivars were planted in two locations of Hebei Province,China from 2015 to 2018(eight environments).Based on a high-density genetic linkage map(including 2996 SNP and 330 SSR markers)previously constructed in our laboratory,QTLs were analyzed using phenotypic data and the best linear unbiased prediction(BLUP)value of initial flowering date by inclusive composite interval mapping(ICIM)*** effects between every two QTLs and between individual QTL and environment were also *** cultivated peanut,IFD was affected by genotypic factor and environments simultaneously,and its broad sense heritability(h2)was estimated as 86.8%。Using the IFD phenotypic data from the eight environments,a total of 19 QTLs for IFD were detected,and the phenotypic variation explained(PVE)by each QTL ranged from 1.15 to 21.82%.Especially,five of them were also detected by the BLUP value of *** addition,12 additive QTLs and 35 pairs of epistatic QTLs(62 loci involved)were identifed by the joint analysis of IFD across eight *** QTLs(qIFDB04.1,qIFDB07.1 and qIFDB08.1)located on chromosome B04,B07 and B08 were identified as main-effect QTL for IFD,which had the most potential to be used in peanut *** study would be helpful for the early-maturity and adaptability breeding in cultivated peanut.

关键词： peanut(Arachis hypogaea L.) initial flowering date(IFD) QTL best linear unbiased prediction(BLUP) ICIM

LES method of the tip clearance vortex cavitation in a propelling pump with special emphasis on the cavitation-vortex interaction

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Journal of Hydrodynamics 2020年第6期32卷 1212-1216页

作者： Cheng-zao Han shun Xu Huai-yu Cheng Bin ji Zhi-yuan Zhang State Key Lab of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China Marine Design and Research Institute of China Shanghai200011China

The turbulent cavitating flow around the propelling pump tip clearance is numerically simulated using the large eddy simulation(LES)method coupled with the Zwart-Gerber-Belamri(ZGB)cavitation model to investigate the cavitation-vortex interaction *** calculated cavitation structures around the blades are in a remarkable agreement with the experimental *** distributions of the tip clearance vortex under two cavitation conditions are obtained and *** results show that the cavitation development enhances the vorticity generation and the flow unsteadiness around the tip clearance of a propelling *** are basically located around the cavitation areas,particularly in the tip clearance region,during the *** relative vorticity transport equation is applied for the cavitating turbulent flows and it is further indicated that the vortex stretching term makes the main contribution in the vortex production,and the baroclinic torque and dilation terms are important source terms for the vorticity generation in the cavitating *** addition,the viscous diffusion term and the Coriolis force term are significant in modifying the vorticity field inside the blade tip clearance.

关键词： Tip-clearance cavitation propelling pump large eddy simulation(LES) vorticity transport equation

A New Species of the Genus Nanorana Günther,1896(Anura:Dicroglossidae)from Hengduan Mountains of China

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Asian Herpetological Research 2023年第4期14卷 300-318页

作者： Feirong ji Shengchao SHI shun MA Cheng SHEN Liming CHANG jianping jiANG Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina University of Chinese Academy of Sciences Beijing 100049China Mangkang Biodiversity and Ecological Station Tibet Ecological Safety Monitor NetworkChangdu 854500XizangChina

An integrative study based on morphological data and mitochondrial molecular data of all known Nanorana(sensu stricto)species have revealed a new species from the Hengduan Mountains,*** *** new species can be distinguished from its congers by its:(1)medium body size,SVL 31.3–40.6 mm in adult males(n=12),39.2–48.1 mm in adult females(n=8);(2)absence of subarticular tubercles on fingers,with supernumerary tubercles below the base of the fingers small but distinct;(3)presence of dark dorsal patches without pale margins,generally creamy yellow ventral body basically,bright yellow ventral limbs;(4)small but prominent tympanum;(5)tibio-tarsal joint that reaches to the tympanum or the shoulder when hindlimbs adpressed forward towards body;(6)head length more than 30%of *** addition,the new species can be separated from all other congeners by uncorrected genetic distances:ranging from 2.8%–7.5%of the mitochondrial 12S rRNA,1.1%–2.1%of the 16S rRNA,and 7.5%–11.5%of the COI.

关键词： Hengduan Mountains Nanorana huangi sp.nov. new species taxonomy

Restricted Arc-Connectivity of Harary Digraphs

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Journal of the Operations Research Society of China 2024年第2期12卷 540-547页

作者： jun-Hao Zhang ji-Xiang Meng College of Mathematics and System Science Xinjiang UniversityUrumqi 830046XinJiangChina

The h-restricted arc-connectivity of a digraph is an important parameter to measure fault-tolerance of interconnection *** paper determines that the h-restricted arc-connectivity of the Harary digraph D=G(n;1,2,.:,k)i... 详细信息

关键词： Restricted arc-connectivity λ_(h)(D) Super-λ_(h) λ_(h)-Atom λ_(h)-Superatom

A MIXED MODE FRACTURE CRITERION BASED ON THE MAXIMUM TANGENTIAL STRESS IN BRITTLE INCLUSION

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Acta Mechanica Solida Sinica 2005年第3期18卷 225-233页

作者： ji Changjiang Li Zhonghua Sun jun School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200240 China State Key Laboratory for Mechanical Behavior of Material School of Materials Science and Engineering Xi＇an Jiaotong University Xi＇an 710049 China

A closed-form solution for predicting the tangential stress of an inclusion located in mixed mode Ⅰ and Ⅱ crack tip field was developed based on the Eshelby equivalent inclusion theory. Then a mixed mode fracture criterion, including the fracture direction and the critical load, was established based on the maximum tangential stress in the inclusion for brittle inclusioninduced fracture materials. The proposed fracture criterion is a function of the inclusion fracture stress, its size and volume fraction, as well as the elastic constants of the inclusion and the matrix material. The present criterion will reduce to the conventional one as the inclusion having the same elastic behavior as the matrix material. The proposed solutions are in good agreement with detailed finite element analysis and measurement.

关键词： mixed mode Ⅰ and Ⅱ crack fracture toughness inclusion Eshelby inclusion theory

Bogdanov-Takens Bifurcation in a Leslie-Gower Predator-prey Model with Prey Harvesting

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Acta Mathematicae Applicatae Sinica 2014年第1期30卷 239-244页

作者： Yi-jun GONG ji-cai HUANG School of Mathematics and Statistics Central China Normal University

This paper discuss the cusp bifurcation of codimension 2 （i.e. Bogdanov-Takens bifurcation） in a Leslie^Gower predator-prey model with prey harvesting, which was not revealed by Zhu and Lan [Phase portraits, Hopf bifurcation and limit cycles of Leslie-Gower predator-prey systems with harvesting rates, Discrete and Continuous Dynamical Systems Series B. 14（1）（2010）, 289-306]. It is shown that there are different parameter values for which the model has a limit cycle or a homoclinic loop.

关键词： Leslie-Gower predator-prey model Bogdanov-Takens bifurcation limit cycle homoclinic loop

Energy Scattering Theory for Electromagnetic NLS in Dimension Two

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Acta Mathematica Sinica,English Series 2018年第4期34卷 641-654页

作者： jun Yong ZHANG ji Qiang ZHENG Department of Mathematics Beijing Institute of Technology Beijing 100081 P. R. China Beijing Computational Science Research Center Beijing 100193 P. R. China Department of Mathematics Universitd Nice Sophia-Antipolis 06108 Nice Cedex 02 France

We study the well-posedness and long-time behavior of solution to both defocusing and focusing nonlinear Schrodinger equations with scaling critical magnetic potentials in dimension two. In the defocusing case, and under the assumption that the initial data is radial, we prove interaction Morawetz-type inequalities and show the scattering holds in the energy space. The magnetic potential considered here is the Aharonov-Bohm potential which decays likely the Coulomb potential {x}-1.

关键词： Nonlinear Schrodinger equations Aharonov-Bohm potential global well-posedness scat-tering