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Genetic Diversity of Hordeum bogdanii Wilensky Native to Xinjiang, China, Based on STS-PCR Markers 被引量:2
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作者 郭红 魏育明 +1 位作者 陈放 郑有良 《Acta Botanica Sinica》 CSCD 2002年第11期1327-1332,共6页
The genetic diversity among 32 accessions of Hordeum bogdanii Wilensky native to Xinjiang, China, was evaluated by 22 STS_PCR primer sets derived from RFLP clones of the wheat ( Triticum aestivum L.) or barley ... The genetic diversity among 32 accessions of Hordeum bogdanii Wilensky native to Xinjiang, China, was evaluated by 22 STS_PCR primer sets derived from RFLP clones of the wheat ( Triticum aestivum L.) or barley ( Hordeum vulgare L.) mapping. Out of the 22 STS_PCR markers, only three markers gave products which did not generate polymorphic bands upon digestion with Hin fⅠ, Hha Ⅰ, Hae Ⅲ and Rsa Ⅰ, while 19 out of 22 markers (86.4%) and 46 out of 88 marker/enzyme combinations (52.3%) revealed polymorphisms. Among the 32 H. bogdanii accessions, a total of 315 bands were observed in 88 STS_PCR marker/enzyme combinations, with 3.6 bands each. One hundred and twenty_three out of 315 bands (39.0%) were polymorphic, among which 1 to 6 polymorphic bands were generated by each polymorphic marker/enzyme combination. The STS_PCR_based genetic diversity index ( GD ) among 32 H. bogdanii accessions ranged between 0.078 to 0.352, with a mean of 0.198. Based on the GD matrix, a dendrogram showing the genetic relationships between accessions was constructed using the unweighted pair_group method with arithmetic average (UPGMA). Results showed that all 32 accessions could be distinguished by STS_PCR markers. The accessions originated from the same region were distributed within different groups or subgroups. This study indicates that the genetic diversity of H. bogdanii is not closely correlated with the geographical distribution. 展开更多
关键词 Hordeum bogdanii STS_PCR marker genetic diversity genetic relationship
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Light Propagation in the Second post-Newtonian Approximation of Scalar-Tensor Theory of Gravity 被引量:2
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作者 DONG Peng LI Lei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期457-461,共5页
In this paper, we use the metric coefficients and the equation of motion obtained in the second post- Newtonian approximation of scalar-tensor theory to derive the second-order light propagation equation and the light... In this paper, we use the metric coefficients and the equation of motion obtained in the second post- Newtonian approximation of scalar-tensor theory to derive the second-order light propagation equation and the light deflection angle and compare it with previous works. These results are useful for precision astrometry missions like ASTROD, GALA, Darwin and SIM which aim at astrometry with micro-arcsecond and nano-aresecond accuracies, and need for the second post-Newtonian framework and ephemeris for observations to determine the stellar and spacecraft positions. 展开更多
关键词 post-Newtonian approximation scalar-tensor theory light propagation
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Generalized Virial Theorem for Mixed State When Hamiltonians Include Coordinate-Momentum Couplings
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作者 WANG Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1173-1176,共4页
The generalized Virial theorem for mixed state, derived from the generalized Hellmann Feynman theorem, only applies to Hamiltonians in which potential of coordinates is separate from momentum energy term. In this pape... The generalized Virial theorem for mixed state, derived from the generalized Hellmann Feynman theorem, only applies to Hamiltonians in which potential of coordinates is separate from momentum energy term. In this paper we discuss Virial theorem for mixed state for some Hamiltonians with coordinate-momentum couplings in order to know their contributions to internal energy. 展开更多
关键词 generalized Virial theorem mixed state
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Biomarkers of neurodegenerative disorders: How good are they? 被引量:15
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作者 VarunRACHAKONDA TianHongPAN WeiDongLE 《Cell Research》 SCIE CAS CSCD 2004年第5期347-358,共12页
Biomarkers are very important indicators of normal and abnormal biological processes. Specific changes in pathologies, biochemistries and genetics can give us comprehensive information regarding the nature of any part... Biomarkers are very important indicators of normal and abnormal biological processes. Specific changes in pathologies, biochemistries and genetics can give us comprehensive information regarding the nature of any particular disease. A good biomarker should be precise and reliable, distinguishable between normal and interested disease, and differential between different diseases. It is believed that biomarkers have great potential in predicting chances for diseases, aiding in early diagnosis, and setting standards for the development of new remedies to treat diseases. New technologies have enabled scientists to identify biomarkers of several different neurodegenerative diseases. The followings, for instance, are only a few of the many new biomarkers that have been recently identified: the phosphorylated tau protein and aggregated β-amyloid peptide for Alzheimer’s disease (AD), α-synuclein contained Lewy bodies and altered dopamine transporter (DAT) imaging for Parkinson’s disease (PD), SOD mutations for familial amyotrophic lateral sclerosis (ALS), and CAG repeats resulted from Huntington’s gene mutations in Huntington’s disease (HD). This article will focus on the most-recent findings of biomarkers belonging to the four mentioned neurodegenerative diseases. 展开更多
关键词 Alzheimer’s disease Parkinson’s disease Amyotrophic Lateral Sclerosis Huntington’s disease biomarkers.
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Treatment of Dirac Fields in Light—Front Coordinates by Dirac‘s Method for Constrained Hamiltonian Systems
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作者 YANGZe-Sen LIUPeng 等 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第1期55-58,共4页
Dirac's method which itself is for constrained Boson fields and particle systems is followed and developed to treat Dirac fields in light-front coordinates.
关键词 Dirac fields in light-front coordinates Dirac's method for constrained Hamiltonian systems
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Complete Assignment and Benchmarking of an 8-Qubit System
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作者 Virginia Jaiuregui-Villanueva Guanru Feng +1 位作者 Jingfu Zhang Raymond Laflamme 《Journal of Physical Science and Application》 2013年第5期301-311,共11页
In this paper, the assignment of acomplex 8-spin-half system (7,7-dichloro-6-oxo-2-tio-bicycle [3.2.0] heptane-4-carboxlic acid) using nuclear magnetic resonance (NMR) techniques is presented and the hamiltonian o... In this paper, the assignment of acomplex 8-spin-half system (7,7-dichloro-6-oxo-2-tio-bicycle [3.2.0] heptane-4-carboxlic acid) using nuclear magnetic resonance (NMR) techniques is presented and the hamiltonian obtained, was used to demonstrate universal control. The system has 313C and 51H,in our work, we carried out traditional 1-D and 2-D experiments and also made use of coherent control together with simulation to get the full hamiltonian of this weakly coupled system. Spin-echo J-resolved 2-D experiments were used to obtain the heteronuclear and homonuclear coupling values; COSY45 experiments were used to obtain the signs of homonuclear coupling constants. The signs of heteronuclear coupling constants were obtained using the polarization transfer method. All the data obtained in the experiments were used in the simulation of the 1-D spectra and then optimized using the least square fitting method. After obtaining the full hamiltonian of the 8-spin system, we used it in QIP, prepared pseudopure states and implemented 1-qubit and 2-qubit gates on one of its 6-qubit subsystems. 展开更多
关键词 NMR 1H 13C quantum computing selective 2D-Jresolved seI-COSY45 13C enriched compound 8-qubit system quantum gates pseudopure states.
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正确解读标语言
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作者 安生夫 《垂钓》 2004年第2期21-21,共1页
关键词 钓鱼 浮标 标语言 拖标 顶标 走标 抖标 顿标 截标 闪标
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Two-post-Newtonian approximation of the scalar-tensor theory with an intermediate-range force for general matter
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作者 DENG XueMei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第3期8-15,共8页
Some future space missions measure distances of laser links and angles with unprecedented precision, allowing us to test theories of gravity up to the two-post-Newtonian (2PN) order. Besides, investigation of an int... Some future space missions measure distances of laser links and angles with unprecedented precision, allowing us to test theories of gravity up to the two-post-Newtonian (2PN) order. Besides, investigation of an intermediate-range force has been of considerable interests in gravitational experiments. Inspired by these ideas, within the framework of the scalar-tensor theory with an intermediate- range force, its 2PN approximation is obtained with Chandrasekhar's approach. It includes the 2PN metric and equations of motion for general matter without specific equation of state. The conserved quantities to the 2PN order are isolated with the aid of the energy-momentum complex. We also discuss the prospect of testing and distinguishing the intermediate-range force with the orbital motions of celestial bodies and spaeecrafts. 展开更多
关键词 GRAVITATION intermediate-range force post-Newtonian approximation
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Hamiltonian Analysis of 3-Dimensional Connection Dynamics in Bondi-like Coordinates
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作者 黄超光 孔师碑 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第8期227-235,共9页
The Hamiltonian analysis for a 3-dimensional connection dynamics of o(1, 2), spanned by {L-+, L-2, L+2) instead of {Lol, L02, L12}, is first conducted in a Bondi-like coordinate system. The symmetry of the system... The Hamiltonian analysis for a 3-dimensional connection dynamics of o(1, 2), spanned by {L-+, L-2, L+2) instead of {Lol, L02, L12}, is first conducted in a Bondi-like coordinate system. The symmetry of the system is clearly presented. A null coframe with 3 independent variables and 9 connection coefficients are treated as basic configuration variables. All constraints and their consistency conditions, the solutions of Lagrange multipliers as well as the equations of motion are presented. There is no physical degree of freedom in the system. The Bafiados-Teitelboim-Zanelli (BTZ) spaeetime is discussed as an example to check the analysis. Unlike the ADM formalism, where only non-degenerate geometries on slices are dealt with and the Ashtekar formalism, where non-degenerate geometries on slices are mainly concerned though the degenerate geometries may be studied as well, in the present formalism the geometries on the slices are always degenerate though the geometries for the spacetime are not degenerate. 展开更多
关键词 3d gravity Hamiltonian analysis connection dynamics Bondi-like coordinate system
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B^0-B^0 Mixing in Local Gauged Baryon and Lepton Numbers
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作者 孙飞 冯太傅 +3 位作者 罗国慧 赵树民 孙科盛 寇丽娜 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第12期721-726,共6页
Using the effective Hamiltonian method, we analyze the B0-B0 mixing in the extension of the standard model (SM) where baryon number and lepton number are local gauge symmetries. The numerical results indicate the co... Using the effective Hamiltonian method, we analyze the B0-B0 mixing in the extension of the standard model (SM) where baryon number and lepton number are local gauge symmetries. The numerical results indicate the correction from the extra particles to the mass difference ArnB is significant. There is a 60% enhancement compared to the SM prediction for AraB at most, which agrees with the current experimental result. 展开更多
关键词 B0-B0 mixing Baryon number local gauge symmetry effective Hamiltonian
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Physiological Flow of Jeffrey Six Constant Fluid Model due to Ciliary Motion 被引量:1
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作者 A.Shaheen S.Hussain S.Nadeem 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第12期701-708,共8页
The main purpose of this article is to present a mathematical model of ciliary motion in an annulus. In this analysis, the peristaltic motion of non-Newtonian Jeffrey six constant fluid is observed in an annulus with ... The main purpose of this article is to present a mathematical model of ciliary motion in an annulus. In this analysis, the peristaltic motion of non-Newtonian Jeffrey six constant fluid is observed in an annulus with ciliated tips in the presence of heat and mass transfer. The effects of viscous dissipation are also considered. The flow equations of non-Newtonian fluid for the two-dimensional tube in cylindrical coordinates are simplified using the low Reynolds number and long wave-length approximations. The main equations for Jeffrey six constant fluid are considered in cylindrical coordinates system. The resulting nonlinear problem is solved using the regular perturbation technique in terms of a variant of small dimensionless parameter α. The results of the solutions for velocity, temperature and concentration field are presented graphically. B_k is Brinkman number, ST is soret number, and SH is the Schmidth number. Outcome for the longitudinal velocity, pressure rise, pressure gradient and stream lines are represented through graphs. In the history, the viscous-dissipation effect is usually represented by the Brinkman number. 展开更多
关键词 ciliary motion metachronal wave Jeffrey six-constant fluid viscous dissipation effects and perturbation method
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Resonances of Spin-1/2 Fermions in Eddington-Inspired Born-Infeld Gravity
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作者 付启明 赵力 +1 位作者 杜云芝 古宝珉 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第3期292-300,共9页
We investigate the fermionic resonances for both chiralities in five-dimensional Eddington-inspired BornInfeld(EiBI)theory.In order to localize fermion on the brane,it needs to be considered the Yukawa coupling betwee... We investigate the fermionic resonances for both chiralities in five-dimensional Eddington-inspired BornInfeld(EiBI)theory.In order to localize fermion on the brane,it needs to be considered the Yukawa coupling between the fermion and the background scalar field.In our models,since the background scalar field has kink,double kink,or anti-kink solution,the system has rich resonant Kaluza-Klein(KK)modes structure.The massive KK fermionic modes feel a volcano potential,which result in a fermionic zero mode and a set of continuous massive KK modes.The inner structure of the branes and a free parameter in background scalar field influence the resonant behaviors of the massive KK fermions. 展开更多
关键词 FERMION resonance EiBI gravity
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Uniqueness of First Order Post-Newtonian Collinear Solutions for Three-Body Problem under a Scalar-Tensor Theory
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作者 曹伟光 周天倚 谢懿 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第10期455-462,共8页
As a continuing investigation of an earlier work that establishes the cofiinear solutions to the three-body problem with general masses under a scalar-tensor theory, we study these solutions and prove their uniqueness... As a continuing investigation of an earlier work that establishes the cofiinear solutions to the three-body problem with general masses under a scalar-tensor theory, we study these solutions and prove their uniqueness up to the first order post-Newtonian approximation. With the help of observed bounds on the scalar field in the Solar System, we show that the seventh-order polynomial equation determining the distance ratio among the three masses has either one or three positive roots. However, in the case with three positive roots, it is found that two positive roots break down the slow-motion condition for the post-Newtonian approximation so that only one positive root is physically valid. The resulting uniqueness suggests that the locations of the three masses are very close to their Newtonian positions with post-Newtonian corrections of general relativity and the scalar field. We also prove that, in the framework of the scalar-tensor theory, the angular velocity of the collinear configuration is always less than the Newtonian one when all other parameters are fixed. These results are valid only for three-body systems where upper-bounds on the scalar field are compatible with those of the Solar System. 展开更多
关键词 scalar-tensor theory THREE-BODY
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