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Testing local realism in P → VV decays

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Science China(Physics,Mechanics & Astronomy) 2010年第5期53卷 870-875页

作者： LI JunLi1 & QIAO CongFeng1,2 1department of Physics,graduate University of chinese{3. of sciences,beijing 100049,China 2Theoretical Physics Center for Science Facilities(TPCSF),chinese{3. of sciences,beijing 100049,China department of Physics Graduate University of Chinese Academy of Sciences Beijing China Theoretical Physics Center for Science Facilities (TPCSF) Chinese Academy of Sciences Beijing China

It was found that the vector meson pair from the pseudoscalar decays can form an entangled *** this work we give out detailed explanations on the polarization correlation of the two entangled vector *** is demonstrated that an experimental test of the Clauser-Horne inequality can be carried out through measuring the azimuthal distribution of four pseudoscalars in the cascade decay ηc→ VV →(PP)(PP),and the measurement of this process is feasible with the current running experiments in tau-charm ***,a brief discussion on the polarization correlation of the two vector mesons from B → VV decays is also presented.

关键词： nonlocality test high energy experiment meson decays

Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural Science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1,2 *, YUAN Yunbin1, OU Jikun1 and CHEN Jinping3.1. Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 43.077, China 2.{3., beijing 10003., China 3. department of Precision Instrument and Mechanology, Tsinghua University, beijing 100084, China) Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China graduate school Chinese Academy of Sciences Beijing 100039 China department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS Ionospheric eclipse factor Ionospheric influence factor

Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG Yuxiu , WANG Zi and XU Jin (department of Bioengineering, school of Chemical and Environmental Engineering, China University of Mining and Technology (beijing), beijing 100083. China department of Biology, graduate University of chinese academy of sciences, beijing 100049, China) department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beijing) Beijing 100083 China department of Biology Graduate University Chinese Academy of Sciences Beijing 100049 China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.

Molecular identification of species in Prunus sect. Persica (Rosaceae), with emphasis on evaluation of candidate barcodes for plants

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Journal of Systematics and Evolution 2011年第2期49卷 138-145页

作者： 1,2 Xu QUAN 1 Shi-Liang ZHOU 1 (State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, chinese academy of sciences,{3. 100093. China) 2 (graduate school of the chinese academy of sciences, beijing 100049, China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate school of the chinese{3. of sciences Beijing 100049 China)

Species of Prunus L. sect. Persica are not only important fruit trees, but also popular ornamental and medicinal plants. Correct identification of seedlings, barks, or fruit kernels is sometimes required, but no reliable morphological characters are available. Nowadays, the technique of DNA barcoding has the potential to meet such requirements. In this study, we evaluated the suitability of 11 DNA loci (atpB-rbcL, trnH-psbA, trnL-F, trnS-G, atpF-H, rbcL, matK, rpoB, rpoC1, nad1, and internal transcribed spacer [ITS]) as candidate DNA barcodes for peaches, using samples from 3. populations, covering all the species in sect. Persica. On the whole, the primers worked well in this group and sequencing difficulties were met only in the case of ITS locus. Five loci (rbcL, matK, rpoB, rpoC, and nad1) have very low variation rates, whereas atpB-rbcL, atpF-H, trnH-psbA, trnL-F and trnS-G show more variability. The most variable loci, atpB-rbcL and trnH-psbA, can distinguish three of the five species. Two two-locus combinations, atpB-rbcL+trnL-F and atpB-rbcL+atpF-H, can resolve all five species. We also find that identification powers of the loci are method-dependent. The NeighborNet method shows higher species identification power than maximum parsimony, neighbor joining, and unweighted pair group method with arithmetic mean methods.

关键词： atpB-rbcL DNA barcode Prunus sect. Persica trnL-F.

MicroRNA (miR3.6) negatively regulates expression of ceramidase-like genes in Arabidopsis

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Progress in Natural Science:Materials International 2009年第6期19卷 781-785页

作者： Dongmei Liu a,b, Diqiu Yu a, a Xishuangbanna Tropical Botanical Garden, chinese academy of sciences, Kunming 650223. China b{3. school of the chinese academy of sciences, beijing 100049, China Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China graduate school of the chinese{3. of sciences Beijing 100049 China

MicroRNAs (miRNAs) are 21-23.nucleotide (nt), endogenous RNAs that regulate gene expression by targeting mRNAs for direct cleavage or translational repression in plants. In Arabidopsis, miR3.6 is encoded by two different loci (MIR3.6a and MIR3.6b) and sequence analysis suggests it may target three ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2 and Atceramidase-like 3.. To demonstrate the biological function of miR3.6, we inserted the synthetic precursors, MIR3.6a or MIR3.6b, under the control of the enhanced cauliflower mosaic virus (CaMV) 3.S promoter, into a plant transformation vector (pOCA3.) and transformed the constructs into Arabidopsis. The promoter increased miR3.6 levels by more than 2-fold, indicating appropriate maturation of the synthetic precursor MIR3.6a or MIR3.6b transcript in transgenic plants. Microarray analysis showed that the transcript levels of two ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2) were decreased by more than 2-fold and lactosylceramide 4-a-galactosyltransferase increased by more than 2-fold in transgenic plants compared with the empty vector-transformed plants. Northern blot analysis showed that the mRNA levels of the two ceramidase-like genes were significantly reduced in transgenic plants. These results indicated that miR3.6 probably plays a crucial role in the ceramide metabolism pathway by negatively regulating the expression of ceramidase-like genes in Arabidopsis.

关键词： miR3.6 miR3.6 precursor Ceramidase Ceramide

Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3., HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4 , ZHANG Shu 2 & ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, chinese academy of sciences,{3. 100012, China 2 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences, beijing 100049, China 3.graduate University of the chinese academy of sciences, beijing 100049, China 4 {13. of Physics, Nanjing Normal University, Nanjing 210011, China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China graduate University of the chinese academy of{3. Beijing China department of Physics Nanjing Normal University Nanjing China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

Hedychium menghaiense (Zingiberaceae),a new species from Yunnan,China

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Journal of Systematics and Evolution 2010年第2期48卷 146-151页

作者： 1,2,3.iu HU 1Nian LIU 1(Zhongkai University of Agriculture and Engineering,Guangzhou 510225,China) 2(South China Botanical Garden,chinese academy of sciences,Guangzhou 510650,China) 3.{3. school of chinese academy of sciences,beijing 100049,China) (Zhongkai University of Agriculture and Engineering Guangzhou 510225 China) (South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (graduate school of chinese{3. of sciences Beijing 100049 China)

Hedychium menghaiense *** & ***,a new species of the Zingiberaceae from Yunnan Province,China,is described and *** new species is currently known only from its type locality,Nannuoshan Mountain,Menghai County,growing under evergreen broad-leaved forests at altitudes of 1400-1700 *** is similar to Hedychium forrestii Diels,but differs in its narrower and emarginate labellum folded inwards lengthwise,narrower staminodes,and scarlet *** recognition of the new species is supported by the results from analysis of sequence-related amplified polymorphism markers.

关键词： Hedychium Hedychium menghaiense X.Hu & N.Liu new species SRAP markers Zingiberaceae

Morphological characteristics of leaf epidermis and size variation of leaf,flower and fruit in different ploidy levels in Buddleja macrostachya (Buddlejaceae)

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Journal of Systematics and Evolution 2009年第3期47卷 231-236页

作者： 1,2Gao CHEN 1Wei-Bang SUN 3.ang SUN 1(Kunming Botanical Garden, Kunming Institute of Botany, chinese academy of sciences, Kunming 650204, China) 2({3. school of chinese academy of sciences, beijing 100049, China) 3.Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, chinese academy of sciences, Kunming 650204, China) (Kunming Botanical Garden Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate school of chinese{3. of sciences Beijing 100049 China) (Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

Buddleja macrostachya (Buddlejaceae) is a widespread shrub native to the Sino-Himalayan mountains and beyond. It has been found to occur at two ploidy levels, hexaploid, 2n=6x=114 and dodecaploid, 2n=12x=228. To determine if morphological characters might be used as indicators of ploidy levels, we measured floral and fruit length, relative and absolute leaf size, trichome density on both leaf surfaces, and stomatal density and length in different populations of B. macrostachya. In general, flower and fruit length, absolute leaf size, and stomatal length increased with an increase at ploidy level (P0.05) in different populations. Other characters studied such as trichome type, cuticular membrane and ornamentation of stomata, cell and stomatal shape, and anticlinal wall pattern were quite constant in this species. Thus it appears that flower and fruit length, absolute leaf size, and stomatal frequency and length can be used to distinguish hexaploid from dodecaploid cytotypes either in the fleld or in herbarium specimens.

关键词： Buddleja macrostachya dodecaploid hexaploid leaf epidermis ploidy level stomata.

Improvement of a 3. radar backscattering model using matrix-doubling method

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Science China Earth sciences 2010年第7期53卷 1029-1035页

作者： NI WenJian1,2, GUO ZhiFeng1 & SUN GuoQing3.1 State Key Laboratory of Remote Sensing Science, jointly sponsored by the Institute of Remote Sensing Applications of chinese academy of sciences and{3. Normal University,{3. 100101, China 2 graduate University of chinese academy of sciences, beijing 100049, China 3.department of Geography, University of Maryland, College Park, MD 27042, USA State Key Laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China graduate University of chinese academy of{3. Beijing China department of Geography University of Maryland College Park USA

Radiative transfer models have been widely used to simulate the radar backscattering from forested areas. A three-dimensional radar backscatter model of forest canopy developed in previous studies takes full account of spatial position of trees in a forest stand, and the interactions among crown, trunk and ground surface. The model predicted well for the co-polarized backscatter measurements, but underestimated the backscattering for cross-polarization, primarily because only the first-order scattering within tree crowns was considered in the model. The backscattering at cross-polarization depends strongly on multiple scatter- ing within tree crowns. To produce good estimations for cross-polarized component, the matrix-doubling method is employed here to compute multiple-scattering within the crown. The modified model is compared with the original model, and the field forest measurements and AIRSAR data are used for validation of the modified model. The cross-polarization backscattering is improved in different degrees for different crown structures and at different bands.

关键词： remote sensing forestry electromagnetic propagation radar backscattering model matrix-doubling