4,674 research outputs found
A study to determine similarities and variances among medical-surgical nursing instructors in rating selected science principles underlying the nursing care of a patient with an ileostomy
Thesis (M.S.)--Boston Universit
From Skew-Cyclic Codes to Asymmetric Quantum Codes
We introduce an additive but not -linear map from
to and exhibit some of its interesting
structural properties. If is a linear -code, then is an
additive -code. If is an additive cyclic code then
is an additive quasi-cyclic code of index . Moreover, if is a module
-cyclic code, a recently introduced type of code which will be
explained below, then is equivalent to an additive cyclic code if is
odd and to an additive quasi-cyclic code of index if is even. Given any
-code , the code is self-orthogonal under the trace
Hermitian inner product. Since the mapping preserves nestedness, it can be
used as a tool in constructing additive asymmetric quantum codes.Comment: 16 pages, 3 tables, submitted to Advances in Mathematics of
Communication
Daily and seasonal variations in the spatial distribution of zooplankton populations in relation to the physical structure in the Ligurian Sea Front
Results from five hydrographic and biological surveys at different seasons across the Ligurian Sea front, using horizontal continuous measurements and vertical profiles are presented. The vertical circulation across the front is described, and two divergences and one convergence are identified as permanent features from data. The key to find their location for each survey is given. The spatial patterns of 14 zooplankton taxa along the transect are established using variance analysis, principal component and correspondence analyses. The spatial distribution of each taxon is related to the physical structure, and the convection cells evidenced by the scheme appear as different biotopes. The daily variability of the spatial distributions is negligible compared to the annual variability. Distinctions are made between coastal species always inhabiting the peripheral (coastal zone) and others with distinct coastal, frontal and offshore distributions varying with the season. For the latter species the frontal zone is a preferential biotope during their seasonal growth period. Consequently the accumulation of organisms near the convergence cannot be created by only the dynamic causes. The role of biological processes in the observed distributions is discussed
A magnetic model for the incommensurate I phase of spin-Peierls systems
A magnetic model is proposed for describing the incommensurate I phase of
spin-Peierls systems. Based on the harmonicity of the lattice distortion, its
main ingredient is that the distortion of the lattice adjusts to the average
magnetization such that the system is always gapful. The presence of dynamical
incommensurabilities in the fluctuation spectra is also predicted. Recent
experimental results for CuGeO_3 obtained by NMR, ESR and light scattering
absorption are well understood within this model.Comment: 8 pages, 3 figures, Latex with EPL style files all include
Introducing the Dark Energy Universe Simulation Series (DEUSS)
In this "Invisible Universe" proceedings, we introduce the Dark Energy
Universe Simulation Series (DEUSS) which aim at investigating the imprints of
realistic dark energy models on cosmic structure formation. It represents the
largest dynamical dark energy simulation suite to date in term of spatial
dynamics. We first present the 3 realistic dark energy models (calibrated on
latest SNIa and CMB data): LambdaCDM, quintessence with Ratra-Peebles
potential, and quintessence with Sugra potential. We then isolate various
contributions for non-linear matter power spectra from a series of pre-DEUSS
high-resolution simulations (130 million particles). Finally, we introduce
DEUSS which consist in 9 Grand Challenge runs with 1 billion particles each
thus probing scales from 4 Gpc down to 3 kpc at z=0. Our goal is to make these
simulations available to the community through the "Dark Energy Universe
Virtual Observatory" (DEUVO), and the "Dark Energy Universe Simulations" (DEUS)
consortium.Comment: 6 pages, 3 figures, to appear in the AIP proceedings of the
'Invisible Universe International Conference', UNESCO-Paris, June 29-July 3,
200
Quantum internal modes of solitons in 1d easy-plane antiferromagnet in strong magnetic field
In presence of a strong external magnetic field the dynamics of solitons in a
one-dimensional easy-plane Heisenberg antiferromagnet exhibits a number of
peculiarities. Dynamics of internal soliton degrees of freedom is essentially
quantum, and they are strongly coupled to the "translational" mode of soliton
movement. These peculiarities lead to considerable changes in the response
functions of the system which can be detected experimentally.Comment: 8 pages, RevTeX, 6 figures, uses psfig.sty, submitted to PR
On the Asymptotic Stability of De-Sitter Spacetime: a non-linear perturbative approach
We derive evolution and constraint equations for second order perturbations
of flat dust homogeneous and isotropic solutions to the Einstein field
equations using all scalar, vector and tensor perturbation modes. We show that
the perturbations decay asymptotically in time and that the solutions converge
to the De-Sitter solution. By induction, this result is valid for perturbations
of arbitrary order. This is in agreement with the cosmic no-hair conjecture of
Gibbons and Hawking.Comment: 11 pages, 2 figure
A Cosmological No-Hair Theorem
A generalisation of Price's theorem is given for application to Inflationary
Cosmologies. Namely, we show that on a Schwarzschild--de Sitter background
there are no static solutions to the wave or gravitational perturbation
equations for modes with angular momentum greater than their intrinsic spin.Comment: 9 pages, NCL94 -TP4, (Revtex
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