19,905 research outputs found
Immunoreactive inhibin in human follicular fluid in an ovarian hyperstimulation proramme for in vitro fertilisation: correlations and different forms
A model for the phase separation controlled by doping and the internal chemical pressure in different cuprate superconductors
In the framework of a two-band model, we study the phase separation regime of
different kinds of strongly correlated charge carriers as a function of the
energy splitting between the two sets of bands. The narrow (wide) band
simulates the more localized (more delocalized) type of charge carriers. By
assuming that the internal chemical pressure on the CuO layer due to
interlayer mismatch controls the energy splitting between the two sets of
states, the theoretical predictions are able to reproduce the regime of phase
separation at doping higher than 1/8 in the experimental pressure-doping-
phase diagram of cuprates at large microstrain as it appears in overoxygenated
LaCuO.Comment: 8 pages, 5 figures, submitted to Phys. Rev.
Analytical Results for Random Band Matrices with Preferential Basis
Using the supersymmetry method we analytically calculate the local density of
states, the localiztion length, the generalized inverse participation ratios,
and the distribution function of eigenvector components for the superposition
of a random band matrix with a strongly fluctuating diagonal matrix. In this
way we extend previously known results for ordinary band matrices to the class
of random band matrices with preferential basis. Our analytical results are in
good agreement with (but more general than) recent numerical findings by
Jacquod and Shepelyansky.Comment: 8 pages RevTex and 1 Figure, both uuencode
Possibilidades de produção de frutos de açaizeiros em área de terra firme no Estado do Pará.
Publicado também: FRAZÃO, D. A. C.; HOMMA, A. K. O; VIÉGAS, I. de J. M. (Ed.). Contribuição ao desenvolvimento da fruticultura na Amazônia. Belém, PA: Embrapa Amazônia Oriental, 2006. p. 91-97
Large-Eddy Simulations of Fluid and Magnetohydrodynamic Turbulence Using Renormalized Parameters
In this paper a procedure for large-eddy simulation (LES) has been devised
for fluid and magnetohydrodynamic turbulence in Fourier space using the
renormalized parameters. The parameters calculated using field theory have been
taken from recent papers by Verma [Phys. Rev. E, 2001; Phys. Plasmas, 2001]. We
have carried out LES on grid. These results match quite well with direct
numerical simulations of . We show that proper choice of parameter is
necessary in LES.Comment: 12 pages, 4 figures: Proper figures inserte
Iterative Perturbation Theory for Strongly Correlated Electron Systems with Orbital Degeneracy
A new scheme of the iterative perturbation theory is proposed for the
strongly correlated electron systems with orbital degeneracy. The method is
based on the modified self-energy of Yeyati, et al. which interpolates between
the weak and the strong correlation limits, but a much simpler scheme is
proposed which is useful in the case of the strong correlation with orbital
degeneracy. It will be also useful in the study of the electronic structures
combined with the band calculations.Comment: 6 pages, 3 Postscript figures, to appear in J. Phys. Cond. Matte
Running Gluon Mass from Landau Gauge Lattice QCD Propagator
The interpretation of the Landau gauge lattice gluon propagator as a massive
type bosonic propagator is investigated. Three different scenarios are
discussed: i) an infrared constant gluon mass; ii) an ultraviolet constant
gluon mass; iii) a momentum dependent mass. We find that the infrared data can
be associated with a massive propagator up to momenta MeV, with a
constant gluon mass of 723(11) MeV, if one excludes the zero momentum gluon
propagator from the analysis, or 648(7) MeV, if the zero momentum gluon
propagator is included in the data sets. The ultraviolet lattice data is not
compatible with a massive type propagator with a constant mass. The scenario of
a momentum dependent gluon mass gives a decreasing mass with the momentum,
which vanishes in the deep ultraviolet region. Furthermore, we show that the
functional forms used to describe the decoupling like solution of the
Dyson-Schwinger equations are compatible with the lattice data with similar
mass scales.Comment: Version to appear in J. Phys. G. New version include some rewriting
and new analysis. In particular, the section on the running mass is ne
Time-resolved charge detection with cross-correlation techniques
We present time-resolved charge sensing measurements on a GaAs double quantum
dot with two proximal quantum point contact (QPC) detectors. The QPC currents
are analyzed with cross-correlation techniques, which enables us to measure dot
charging and discharging rates for significantly smaller signal-to-noise ratios
than required for charge detection with a single QPC. This allows to reduce the
current level in the detector and therefore the invasiveness of the detection
process and may help to increase the available measurement bandwidth in
noise-limited setups.Comment: 6 pages, 4 figure
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