197 research outputs found
Comparison of genetic diversity and growth traits among Fangzheng silver crucian carp (Carassius auratus gibelio) gynogenetic clones
The silver crucian carp (Carassius auratus gibelio), a gynogenetic teleost, is a promising model for the study of evolutionary genetics in vertebrates. We identified ten gynogenetic clones (FZ-I~FZ-X) from triploid silver crucian carp, collected from Fangzheng County in Heilongjiang Province, China, using microsatellite markers. The genetic diversity of these gynogenetic clones was analyzed using 52 microsatellite markers. A total of 413 alleles were detected and the length of fragments ranged from 96 to 340 bp. The number of alleles per locus varied from 2~19 (mean=7.9423). The observed heterozygosity at polymorphic loci ranged from 0.10~1.00 (mean=0.80). The average allele count per gynogenetic clone ranged from 1.9423~2.1923. The ratio of the polymorphic locus was from 71.15% (VII) to 84.61% (IX) per clone. The number of genotypes ranged from 2~10 per locus. Ten genotypes were observed by analyzing each of 14 microsatellites. As a result, each gynogenetic clone could be accurately identified. In addition, the growth traits, including body weight, length, and height, among five gynogenetic clones were compared. There was a significant difference among gynogenetic clones. Clone FZ-V exhibited the best growth traits, with the largest body weight (53.17±5.24 g), length (11.38±0.37 cm) and height (4.69±0.18 cm). Our results provide basic data for the identification of silver crucian carp gynogenetic clones and can be used as a guide genetic breeding programs
The short-time behaviour of a kinetic Ashkin-Teller model on the critical line
We simulate the kinetic Ashkin-Teller model with both ordered and disordered
initial states, evolving in contact with a heat-bath at the critical
temperature. The power law scaling behaviour for the magnetic order and
electric order are observed in the early time stage. The values of the critical
exponent vary along the critical line. Another dynamical exponent
is also obtained in the process.Comment: 14 pages LaTeX with 4 figures in postscrip
Improved InGaN/GaN light-emitting diodes with a p-GaN/n-GaN/p-GaN/n-GaN/p- GaN current-spreading layer
This work reports both experimental and theoretical studies on the InGaN/GaN light-emitting diodes (LEDs) with optical output power and external quantum efficiency (EQE) levels substantially enhanced by incorporating p-GaN/n-GaN/p-GaN/n-GaN/p-GaN (PNPNP-GaN) current spreading layers in p-GaN. Each thin n-GaN layer sandwiched in the PNPNP-GaN structure is completely depleted due to the built-in electric field in the PNPNP-GaN junctions, and the ionized donors in these n-GaN layers serve as the hole spreaders. As a result, the electrical performance of the proposed device is improved and the optical output power and EQE are enhanced. © 2013 Optical Society of America
A study of charged kappa in
Based on events collected by BESII, the decay
is studied. In the invariant mass
spectrum recoiling against the charged , the charged
particle is found as a low mass enhancement. If a Breit-Wigner function of
constant width is used to parameterize the kappa, its pole locates at MeV/. Also in this channel,
the decay is observed for the first time.
Its branching ratio is .Comment: 14 pages, 4 figure
Measurements of the observed cross sections for exclusive light hadrons containing at , 3.650 and 3.6648 GeV
By analyzing the data sets of 17.3, 6.5 and 1.0 pb taken,
respectively, at , 3.650 and 3.6648 GeV with the BES-II
detector at the BEPC collider, we measure the observed cross sections for
, , ,
and at the three energy
points. Based on these cross sections we set the upper limits on the observed
cross sections and the branching fractions for decay into these
final states at 90% C.L..Comment: 7 pages, 2 figure
Partial wave analysis of J/\psi \to \gamma \phi \phi
Using events collected in the BESII detector, the
radiative decay is
studied. The invariant mass distribution exhibits a near-threshold
enhancement that peaks around 2.24 GeV/.
A partial wave analysis shows that the structure is dominated by a
state () with a mass of
GeV/ and a width of GeV/. The
product branching fraction is: .Comment: 11 pages, 4 figures. corrected proof for journa
Direct Measurements of Absolute Branching Fractions for D0 and D+ Inclusive Semimuonic Decays
By analyzing about 33 data sample collected at and around 3.773
GeV with the BES-II detector at the BEPC collider, we directly measure the
branching fractions for the neutral and charged inclusive semimuonic decays
to be and , and determine the ratio of the two branching
fractions to be
Bright Strongly Lensed Galaxies at Redshift z~ 6-7 behind the Clusters Abell 1703 and CL0024+161
We report on the discovery of three bright, strongly-lensed objects behind
Abell 1703 and CL0024+16 from a dropout search over 25 square arcminutes of
deep NICMOS data, with deep ACS optical coverage. They are undetected in the
deep ACS images below 8500 A and have clear detections in the J and H bands.
Fits to the ACS, NICMOS and IRAC data yield robust photometric redshifts in the
range z~6-7 and largely rule out the possibility that they are low-redshift
interlopers. All three objects are extended, and resolved into a pair of bright
knots. The bright i-band dropout in Abell 1703 has an H-band AB magnitude of
23.9, which makes it one of the brightest known galaxy candidates at z>5.5. Our
model fits suggest a young, massive galaxy only ~ 60 million years old with a
mass of ~ 1E10 solar mass. The dropout galaxy candidates behind CL0024+16 are
separated by 2.5" (~ 2 kpc in the source plane), and have H-band AB magnitudes
of 25.0 and 25.6. Lensing models of CL0024+16 suggest that the objects have
comparable intrinsic magnitudes of AB ~ 27.3, approximately one magnitude
fainter than L* at z~6.5. Their similar redshifts, spectral energy
distribution, and luminosities, coupled with their very close proximity on the
sky, suggest that they are spatially associated, and plausibly are physically
bound. Combining this sample with two previously reported, similarly magnified
galaxy candidates at z~6-8, we find that complex systems with dual nuclei may
be a common feature of high-redshift galaxies.Comment: 34 pages, 9 figure
Facile Hydrogen Evolution Reaction on WO3Nanorods
Tungsten trioxide nanorods have been generated by the thermal decomposition (450 °C) of tetrabutylammonium decatungstate. The synthesized tungsten trioxide (WO3) nanorods have been characterized by XRD, Raman, SEM, TEM, HRTEM and cyclic voltammetry. High resolution transmission electron microscopy and X-ray diffraction analysis showed that the synthesized WO3nanorods are crystalline in nature with monoclinic structure. The electrochemical experiments showed that they constitute a better electrocatalytic system for hydrogen evolution reaction in acid medium compared to their bulk counterpart
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