33,505 research outputs found
Genuine Multipartite Entanglement in Quantum Phase Transitions
We demonstrate that the Global Entanglement (GE) measure defined by Meyer and
Wallach, J. Math. Phys. 43, 4273 (2002), is maximal at the critical point for
the Ising chain in a transverse magnetic field. Our analysis is based on the
equivalence of GE to the averaged linear entropy, allowing the understanding of
multipartite entanglement (ME) features through a generalization of GE for
bipartite blocks of qubits. Moreover, in contrast to GE, the proposed ME
measure can distinguish three paradigmatic entangled states: ,
, and . As such the generalized measure can detect
genuine ME and is maximal at the critical point.Comment: 4 pages, 3 figures. Replaced with final published versio
Nematic liquid crystal dynamics under applied electric fields
In this paper we investigate the dynamics of liquid crystal textures in a
two-dimensional nematic under applied electric fields, using numerical
simulations performed using a publicly available LIquid CRystal Algorithm
(LICRA) developed by the authors. We consider both positive and negative
dielectric anisotropies and two different possibilities for the orientation of
the electric field (parallel and perpendicular to the two-dimensional lattice).
We determine the effect of an applied electric field pulse on the evolution of
the characteristic length scale and other properties of the liquid crystal
texture network. In particular, we show that different types of defects are
produced after the electric field is switched on, depending on the orientation
of the electric field and the sign of the dielectric anisotropy.Comment: 7 pages, 12 figure
On X-ray-singularities in the f-electron spectral function of the Falicov-Kimball model
The f-electron spectral function of the Falicov-Kimball model is calculated
within the dynamical mean-field theory using the numerical renormalization
group method as the impurity solver. Both the Bethe lattice and the hypercubic
lattice are considered at half filling. For small U we obtain a single-peaked
f-electron spectral function, which --for zero temperature-- exhibits an
algebraic (X-ray) singularity () for . The
characteristic exponent depends on the Coulomb (Hubbard) correlation
U. This X-ray singularity cannot be observed when using alternative
(Keldysh-based) many-body approaches. With increasing U, decreases and
vanishes for sufficiently large U when the f-electron spectral function
develops a gap and a two-peak structure (metal-insulator transition).Comment: 8 pages, 8 figures, revte
Banco de Dados de Genótipos e Fenótipos (BDGF) para suporte a estudos de associação genômica ampla e seleção genômica em programas de melhoramento animal.
Este documento complementa os trabalhos previamente desenvolvidos, apresentando um modelo de dados para armazenamento de dados de genótipos, fenótipos e pedigree de animais de interesse agropecuário para suporte tanto a experimentos de GWAS quanto a programas de melhoramento genético animal, Banco de Dados de Genótipos e Fenótipos(BDGF).bitstream/item/138127/1/Doc133.pd
Diffusion Enhancement in Core-softened fluid confined in nanotubes
We study the effect of confinement in the dynamical behavior of a
core-softened fluid. The fluid is modeled as a two length scales potential.
This potential in the bulk reproduces the anomalous behavior observed in the
density and in the diffusion of liquid water. A series of Molecular
Dynamics simulations for this two length scales fluid confined in a nanotube
were performed. We obtain that the diffusion coefficient increases with the
increase of the nanotube radius for wide channels as expected for normal
fluids. However, for narrow channels, the confinement shows an enhancement in
the diffusion coefficient when the nanotube radius decreases. This behavior,
observed for water, is explained in the framework of the two length scales
potential.Comment: 17 pages, 8 figures, accept for publication at J. Chem. Phy
Transition Matrix Monte Carlo Reweighting and Dynamics
We study an induced dynamics in the space of energy of single-spin-flip Monte
Carlo algorithm. The method gives an efficient reweighting technique. This
dynamics is shown to have relaxation times proportional to the specific heat.
Thus, it is plausible for a logarithmic factor in the correlation time of the
standard 2D Ising local dynamics.Comment: RevTeX, 5 pages, 3 figure
Características físico-químicas de sucos de uvas Isabel Precoce e BRS Violeta elaborados no Nordeste do Brasil.
A avaliação da adaptação de variedades de uva destinadas à elaboração de sucos a determinadas condições de clima e solo requer estudos específicos, contando com uma avaliação analítica do produto elaborado. O objetivo do presente trabalho foi comparar os sucos obtidos a partir de duas variedades de uvas labruscas produzidas no Vale do São Francisco. Os sucos foram elaborados em triplicata pelo método artesanal, a partir de uvas das variedades BRS Violeta e Isabel Precoce. As variáveis analisadas foram pH, sólidos solúveis totais, acidez total e volátil, dióxido de enxofre livre e total, teor alcoólico, índice de cor, antocianinas totais e índice de polifenóis totais (I-280). As médias foram comparadas pelo teste de Tukey a 5% de probabilidade. Apenas para o pH não houve diferença significativa, sendo as demais variáveis significativamente diferentes entre as variedades, nos sucos analisados. A variedade BRS Violeta apresentou excelente potencial para a elaboração comercial de sucos na região
Chaotic Interaction of Langmuir Solitons and Long Wavelength Radiation
In this work we analyze the interaction of isolated solitary structures and
ion-acoustic radiation. If the radiation amplitude is small solitary structures
persists, but when the amplitude grows energy transfer towards small spatial
scales occurs. We show that transfer is particularly fast when a fixed point of
a low dimensional model is destroyed.Comment: LaTex + 4 eps file
Características físico-químicas de sucos de uvas Isabel Precoce e BRS Violeta elaborados no Nordeste do Brasil.
A avaliação da adaptação de variedades de uva destinadas à elaboração de sucos a determinadas condições de clima e solo requer estudos específicos, contando com uma avaliação analítica do produto elaborado. O objetivo do presente trabalho foi comparar os sucos obtidos a partir de duas variedades de uvas labruscas produzidas no Vale do São Francisco. Os sucos foram elaborados em triplicata pelo método artesanal, a partir de uvas das variedades BRS Violeta e Isabel Precoce. As variáveis analisadas foram pH, sólidos solúveis totais, acidez total e volátil, dióxido de enxofre livre e total, teor alcoólico, índice de cor, antocianinas totais e índice de polifenóis totais (I-280). As médias foram comparadas pelo teste de Tukey a 5% de probabilidade. Apenas para o pH não houve diferença significativa, sendo as demais variáveis significativamente diferentes entre as variedades, nos sucos analisados. A variedade BRS Violeta apresentou excelente potencial para a elaboração comercial de sucos na região
- …