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Flexible and Transparent High-Dielectric-Constant Polymer Films Based on Molecular Ferroelectric-Modified Poly(Vinyl Alcohol)
CO J=3-2 Emission from the "Water Fountain" Sources IRAS 16342-3814 and IRAS 18286-0959
We observed CO J=3-2 emission from the "water fountain" sources, which
exhibit high-velocity collimated stellar jets traced by water maser emission,
with the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope. We
detected the CO emission from two sources, IRAS 16342-3814 and IRAS 18286-0959.
The IRAS 16342-3814 CO emission exhibits a spectrum that is well fit to a
Gaussian profile, rather than to a parabolic profile, with a velocity width
(FWHM) of 158+/-6 km/s and an intensity peak at VLSR = 50+/-2 km/s. The mass
loss rate of the star is estimated to be ~2.9x10^-5 M_sun/yr. Our
morpho-kinematic models suggest that the CO emission is optically thin and
associated with a bipolar outflow rather than with a (cold and relatively
small) torus. The IRAS 18286-0959 CO emission has a velocity width (FWHM) of
3.0+/-0.2 km/s, smaller than typically seen in AGB envelopes. The narrow
velocity width of the CO emission suggests that it originates from either an
interstellar molecular cloud or a slowly-rotating circumstellar envelope that
harbors the water maser source.Comment: 10 pages, 4 figure, accepted for publication in the Publications of
the Astronomical Society of Japan, Vol. 61, No.6, 2009 December issu
Transport properties of dense deuterium-tritium plasmas
Consistent descriptions of the equation of states, and information about
transport coefficients of deuterium-tritium mixture are demonstrated through
quantum molecular dynamic (QMD) simulations (up to a density of 600 g/cm
and a temperature of eV). Diffusion coefficients and viscosity are
compared with one component plasma model in different regimes from the strong
coupled to the kinetic one. Electronic and radiative transport coefficients,
which are compared with models currently used in hydrodynamic simulations of
inertial confinement fusion, are evaluated up to 800 eV. The Lorentz number is
also discussed from the highly degenerate to the intermediate region.Comment: 4 pages, 3 figure
Optimal Pole Assignment of Linear Systems by the Sylvester Matrix Equations
The problem of state feedback optimal pole assignment is to design a feedback gain such that the closed-loop system has desired eigenvalues and such that certain quadratic performance index is minimized. Optimal pole assignment controller can guarantee both good dynamic response and well robustness properties of the closed-loop system. With the help of a
class of linear matrix equations, necessary and sufficient conditions for the existence of a solution to the optimal pole assignment problem are proposed in this paper. By properly choosing the free parameters in the parametric solutions to this class of linear matrix equations, complete solutions to the optimal pole assignment problem can be obtained. A numerical example is used to illustrate the effectiveness of the proposed approach
Taxonomic studies on the subtribe Aphrastobraconina Ashmead (Hymenoptera: Braconidae: Braconinae) in China
The species of the subtribe Aphrastobraconina Ashmead from China were studied and five species belonging to three genera (Undabracon Quicke, 1986, Curriea Ashmead, 1900 and Aphrastobracon Ashmead, 1896) recognized. Three new species (Undabracon cariniventris sp. n., Aphrastobracon huanjiangensis sp. n. and A. politus sp. n.) are fully described and illustrated. The genus Undabracon (Quicke, 1986), the species Aphrastobracon flavipennis Ashmead and Curriea tibialis (Ashmead) are reported for the first time from China. A key to the species of the genus Undabracon is provided
Cloning and selection of reference genes for gene expression studies in Ananas comosus
Full length mRNA sequences of Ac-β-actin and Ac-gapdh, and partial mRNA sequences of Ac-18SrRNA and Ac-ubiquitin were cloned from pineapple in this study. The four genes were tested as housekeeping genes in three experimental sets. GeNorm and NormFinder analysis revealed that β-actin was the most appropriate reference gene for qPCR analysis of callus under induction conditions and in different tissue types, meanwhile, 18SrRNA was the most stable reference gene during organ development. Gapdh was the most unstable gene in all tested experimental sets. Transcript level analysis result of AcSERK1 in stressed callus normalized by β-actin and 18SrRNA further confirmed that reference genes selected in this study were suitable for transcript level analysis of pineapple. The expression pattern of AcSERK1 during somatic embryogenesis normalized by β-actin coincided with the cytological features of calluses during somatic embryogenesis. These results will enable more accurate and reliable normalization of qPCR results for transcription analysis in pineapple. Keywords: Reference genes, qPCR, pineapple, geNorm, NormFinder African Journal of Biotechnology Vol. 11(29), pp. 7424-7433, 10 April, 201
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