9,419 research outputs found
The internal transcribed spacer rDNA specific markers for identification of Zanthoxylum piperitum
Genus Zanthoxylum which has significant medical importance belongs to the family Rutaceae. This investigation was aimed to identify total internal transcribed spacer (ITS) regions among the nuclear ribosomal DNA (nrDNA) to distinguish Zanthoxylum piperitum from Zanthoxylum sichinifolium. The nrDNA ITS sequence markers were developed by using universal ITS5/ITS4 primer pairs. Speciesspecific primers amplified the total ITS region sequence named ITS1-YL1 and ITS1-YL2. These were amplified efficiently when paired with universal primer ITS4 in Z. piperitum, but not in Z. schinifolium. ITS1-YL1/ITS4 or ITS1-YL2/ITS4 preferential amplification was shown to be particularly useful for detection and distribution of Z. piperitum from other plant species, especially Z. schinifolium. These primers are useful to study the structure of Rutaceae family. Such identifications will be helpful for phylogenetic analysis in intraspecies population of the genus Zanthoxylum.Key words: Zanthoxylum piperitum, rDNA Int-sp markers, phylogenetic relationship, ribosomal DNA, internal transcribed spacer
Ribosomal DNA internal transcribed spacer 1 and internal transcribed spacer 2 regions as targets for molecular identification of medically important Zanthoxylum schinifolium
Molecular approaches are now being developed to provide a more rapid and objective identification compared to traditional phenotypic methods. Nuclear ribosomal DNA (nrDNA) targets, especially internal transcribed spacer 1 and 2 (ITS1 and ITS2), have been widely used for molecular identification of some plants and fungi. We therefore conducted an investigation in the identification of the fifth medically important Zanthoxylum schinifolium ecotypes using the common primers of the ITS region. About 620 bp fragments were obtained and the sequences of the polymerase chain reaction (PCR) products were tested. The sequence length, G+C content (%), DNA alignment and pariwise nucleotidecomparisons demonstrated 98.8 to 100% sequence identities in the total ITS region, 98.3 to 100% identities in the ITS1 region and 99.5 to 100% in the ITS2 region. Comparative analysis using GenBank reference data showed that the exclusive reported data showed 100% identities with BEMR, CWDO, HCDC, JDGG and GJGD in the ITS1 region and 100% identities with thirteen ecotypes except BEMR and GRDG in the ITS2 region. The fifth different ecotypes were classified into five groups and theidentification of medically important Z. schinifolium was highly improved due to the augmentation of our current ITS sequences
Measurement of Cosmic-ray Muons and Muon-induced Neutrons in the Aberdeen Tunnel Underground Laboratory
We have measured the muon flux and production rate of muon-induced neutrons
at a depth of 611 m water equivalent. Our apparatus comprises three layers of
crossed plastic scintillator hodoscopes for tracking the incident cosmic-ray
muons and 760 L of gadolinium-doped liquid scintillator for producing and
detecting neutrons. The vertical muon intensity was measured to be cmssr. The yield of
muon-induced neutrons in the liquid scintillator was determined to be
neutrons/(gcm). A fit to the recently measured neutron
yields at different depths gave a mean muon energy dependence of for liquid-scintillator targets.Comment: 14 pages, 17 figures, 3 table
Ordered Phases of Itinerant Dzyaloshinsky-Moriya Magnets and Their Electronic Properties
A field theory appropriate for magnets that display helical order due to the
Dzyaloshinsky-Moriya mechanism, a class that includes MnSi and FeGe, is used to
derive the phase diagram in a mean-field approximation. The helical phase, the
conical phase in an external magnetic field, and recent proposals for the
structure of the A-phase and the non-Fermi-liquid region in the paramagnetic
phase are discussed. It is shown that the orientation of the helical pitch
vector along an external magnetic field within the conical phase occurs via two
distinct phase transitions. The Goldstone modes that result from the long-range
order in the various phases are determined, and their consequences for
electronic properties, in particular the specific heat, the single-particle
relaxation time, and the electrical and thermal conductivities, are derived.
Various aspects of the ferromagnetic limit, and qualitative differences between
the transport properties of helimagnets and ferromagnets, are also discussed.Comment: 22pp, 8 eps fig
Effects of metallic spacer in layered superconducting Sr2(MgTi)O3FeAs
The highly two-dimensional superconducting system
Sr2(MgTi)O3FeAs, recently synthesized in the range of 0.2 < y <
0.5, shows an Mg concentration-dependent . Reducing the Mg concentration
from y=0.5 leads to a sudden increase in , with a maximum ~40 K at
y=0.2. Using first principles calculations, the unsynthesized stoichiometric
y=0 and the substoichiometric y=0.5 compounds have been investigated. For the
50% Mg-doped phase (y=0.5), Sr2(MgTi)O3 layers are completely
insulating spacers between FeAs layers, leading to the fermiology such as that
found for other Fe pnictides. At y=0, representing a phase with metallic
Sr2TiO3 layers, the -centered Fe-derived Fermi surfaces (FSs)
considerably shrink or disappear. Instead, three -centered Ti FSs
appear, and in particular two of them have similar size, like in MgB2.
Interestingly, FSs have very low Fermi velocity in large fractions: the lowest
being 0.6 cm/s. Furthermore, our fixed spin moment calculations
suggest the possibility of magnetic ordering, with magnetic Ti and nearly
nonmagnetic Fe ions. These results indicate a crucial role of
Sr2(MgTi)O3 layers in this superconductivity.Comment: 7 pages; Proceedings of ICSM-201
Gravity and Large-Scale Non-local Bias
The relationship between galaxy and matter overdensities, bias, is most often
assumed to be local. This is however unstable under time evolution, we provide
proofs under several sets of assumptions. In the simplest model galaxies are
created locally and linearly biased at a single time, and subsequently move
with the matter (no velocity bias) conserving their comoving number density (no
merging). We show that, after this formation time, the bias becomes unavoidably
non-local and non-linear at large scales. We identify the non-local
gravitationally induced fields in which the galaxy overdensity can be expanded,
showing that they can be constructed out of the invariants of the deformation
tensor (Galileons). In addition, we show that this result persists if we
include an arbitrary evolution of the comoving number density of tracers. We
then include velocity bias, and show that new contributions appear, a dipole
field being the signature at second order. We test these predictions by
studying the dependence of halo overdensities in cells of fixed matter density:
measurements in simulations show that departures from the mean bias relation
are strongly correlated with the non-local gravitationally induced fields
identified by our formalism. The effects on non-local bias seen in the
simulations are most important for the most biased halos, as expected from our
predictions. The non-locality seen in the simulations is not fully captured by
assuming local bias in Lagrangian space. Accounting for these effects when
modeling galaxy bias is essential for correctly describing the dependence on
triangle shape of the galaxy bispectrum, and hence constraining cosmological
parameters and primordial non-Gaussianity. We show that using our formalism we
remove an important systematic in the determination of bias parameters from the
galaxy bispectrum, particularly for luminous galaxies. (abridged)Comment: 26 pages, 9 figures. v2: improved appendix
Heuristic derivation of continuum kinetic equations from microscopic dynamics
We present an approximate and heuristic scheme for the derivation of
continuum kinetic equations from microscopic dynamics for stochastic,
interacting systems. The method consists of a mean-field type, decoupled
approximation of the master equation followed by the `naive' continuum limit.
The Ising model and driven diffusive systems are used as illustrations. The
equations derived are in agreement with other approaches, and consequences of
the microscopic dependences of coarse-grained parameters compare favorably with
exact or high-temperature expansions. The method is valuable when more
systematic and rigorous approaches fail, and when microscopic inputs in the
continuum theory are desirable.Comment: 7 pages, RevTeX, two-column, 4 PS figures include
Constraints on the R-parity- and Lepton-Flavor-Violating Couplings from B0 Decats to Two Charged Leptons
We derive the upper bounds on certain products of R-parity- and
lepton-flavor-violating couplings from the decays of the neutral meson into
two charged leptons. These modes of decays can constrain the product
combinations of the couplings with one or more heavy generation indices. We
find that most of these bounds are stronger than the previous ones.Comment: Table is changed; version to appear in Phys. Rev.
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