427 research outputs found
Effect of Added Lysine to Starter Diets Containing Primarily Zein Protein and Formulated to Provide .14% Tryptophan
Corn gluten meal (CGM) is a by-product of the wet milling corn. It is the residue that remains after the bran, germ and starch have been removed and may contain either 41 or 60% crude protein. There is a temptation to use CGM as an alternative to soybean meal (SBM) when the cost of SBM is high. The 60% protein CGM contains a greater quantity of protein and more threonine, sulfur amino acids, and other neutral amino acids than 44% protein SBM. However, SBM contains greater amounts of lysine and tryptophan. Previous studies with growing and finishing swine indicated that tryptophan is limiting in diets containing CGM, even though the diets were formulated to meet the requirements for tryptophan established by the NRC (1988). The objective of this study was to determine if feed intake is maintained for 10 to 20 kg pigs fed low protein diets containing CGM if crystalline L-lysine-HCL (L-LYS) is added to meet the lysine requirement
Dynamics of earthquake nucleation process represented by the Burridge-Knopoff model
Dynamics of earthquake nucleation process is studied on the basis of the
one-dimensional Burridge-Knopoff (BK) model obeying the rate- and
state-dependent friction (RSF) law. We investigate the properties of the model
at each stage of the nucleation process, including the quasi-static initial
phase, the unstable acceleration phase and the high-speed rupture phase or a
mainshock. Two kinds of nucleation lengths L_sc and L_c are identified and
investigated. The nucleation length L_sc and the initial phase exist only for a
weak frictional instability regime, while the nucleation length L_c and the
acceleration phase exist for both weak and strong instability regimes. Both
L_sc and L_c are found to be determined by the model parameters, the frictional
weakening parameter and the elastic stiffness parameter, hardly dependent on
the size of an ensuing mainshock. The sliding velocity is extremely slow in the
initial phase up to L_sc, of order the pulling speed of the plate, while it
reaches a detectable level at a certain stage of the acceleration phase. The
continuum limits of the results are discussed. The continuum limit of the BK
model lies in the weak frictional instability regime so that a mature
homogeneous fault under the RSF law always accompanies the quasi-static
nucleation process. Duration times of each stage of the nucleation process are
examined. The relation to the elastic continuum model and implications to real
seismicity are discussed.Comment: Title changed. Changes mainly in abstract and in section 1. To appear
in European Physical Journal
Unitary Fermi gas, epsilon expansion, and nonrelativistic conformal field theories
We review theoretical aspects of unitary Fermi gas (UFG), which has been
realized in ultracold atom experiments. We first introduce the epsilon
expansion technique based on a systematic expansion in terms of the
dimensionality of space. We apply this technique to compute the thermodynamic
quantities, the quasiparticle spectrum, and the critical temperature of UFG. We
then discuss consequences of the scale and conformal invariance of UFG. We
prove a correspondence between primary operators in nonrelativistic conformal
field theories and energy eigenstates in a harmonic potential. We use this
correspondence to compute energies of fermions at unitarity in a harmonic
potential. The scale and conformal invariance together with the general
coordinate invariance constrains the properties of UFG. We show the vanishing
bulk viscosities of UFG and derive the low-energy effective Lagrangian for the
superfluid UFG. Finally we propose other systems exhibiting the nonrelativistic
scaling and conformal symmetries that can be in principle realized in ultracold
atom experiments.Comment: 44 pages, 15 figures, contribution to Lecture Notes in Physics
"BCS-BEC crossover and the Unitary Fermi Gas" edited by W. Zwerge
A perturbative approach to decays into two mesons
The modified perturbative approach in which transverse degrees of freedom as
well as Sudakov suppressions are taken into account, is applied to decays
into two mesons. The influence of various model parameters (CKM matrix
elements, decay constant, mesonic wave functions) on the results as well as
short distance corrections to the weak Hamiltonian are discussed in some
detail. The perturbative contributions to the decays yield branching ratios
of the order of which values are well below the upper
limit for the branching ratio as measured by CLEO.Comment: 26 pages, RevTex, 6 figures appended (compressed and uuencode using
'uufiles'
Threshold Electrodisintegration of ^3He
Cross sections were measured for the near-threshold electrodisintegration of
^3He at momentum transfer values of q=2.4, 4.4, and 4.7 fm^{-1}. From these and
prior measurements the transverse and longitudinal response functions R_T and
R_L were deduced. Comparisons are made against previously published and new
non-relativistic A=3 calculations using the best available NN potentials. In
general, for q<2 fm^{-1} these calculations accurately predict the threshold
electrodisintegration of ^3He. Agreement at increasing q demands consideration
of two-body terms, but discrepancies still appear at the highest momentum
transfers probed, perhaps due to the neglect of relativistic dynamics, or to
the underestimation of high-momentum wave-function components.Comment: 9 pages, 7 figures, 1 table, REVTEX4, submitted to Physical Review
Benchmark Test Calculation of a Four-Nucleon Bound State
In the past, several efficient methods have been developed to solve the
Schroedinger equation for four-nucleon bound states accurately. These are the
Faddeev-Yakubovsky, the coupled-rearrangement-channel Gaussian-basis
variational, the stochastic variational, the hyperspherical variational, the
Green's function Monte Carlo, the no-core shell model and the effective
interaction hyperspherical harmonic methods. In this article we compare the
energy eigenvalue results and some wave function properties using the realistic
AV8' NN interaction. The results of all schemes agree very well showing the
high accuracy of our present ability to calculate the four-nucleon bound state.Comment: 17 pages, 1 figure
Large-space shell-model calculations for light nuclei
An effective two-body interaction is constructed from a new Reid-like
potential for a large no-core space consisting of six major shells and is used
to generate the shell-model properties for light nuclei from =2 to 6. (For
practical reasons, the model space is partially truncated for =6.) Binding
energies and other physical observables are calculated and compare favorably
with experiment.Comment: prepared using LaTex, 21 manuscript pages, no figure
Avalanches and the Renormalization Group for Pinned Charge-Density Waves
The critical behavior of charge-density waves (CDWs) in the pinned phase is
studied for applied fields increasing toward the threshold field, using
recently developed renormalization group techniques and simulations of
automaton models. Despite the existence of many metastable states in the pinned
state of the CDW, the renormalization group treatment can be used successfully
to find the divergences in the polarization and the correlation length, and, to
first order in an expansion, the diverging time scale. The
automaton models studied are a charge-density wave model and a ``sandpile''
model with periodic boundary conditions; these models are found to have the
same critical behavior, associated with diverging avalanche sizes. The
numerical results for the polarization and the diverging length and time scales
in dimensions are in agreement with the analytical treatment. These
results clarify the connections between the behaviour above and below
threshold: the characteristic correlation lengths on both sides of the
transition diverge with different exponents. The scaling of the distribution of
avalanches on the approach to threshold is found to be different for automaton
and continuous-variable models.Comment: 29 pages, 11 postscript figures included, REVTEX v3.0 (dvi and PS
files also available by anonymous ftp from external.nj.nec.com in directory
/pub/alan/cdwfigs
Resonances in the three-neutron system
A study of 3-body resonances has been performed in the framework of
configuration space Faddeev equations. The importance of keeping a sufficient
number of terms in the asymptotic expansion of the resonance wave function is
pointed out. We investigated three neutrons interacting in selected force
components taken from realistic nn forces.Comment: 38 pages, 11 tables, 4 figure
The three-nucleon bound state using realistic potential models
The bound states of H and He have been calculated using the Argonne
plus the Urbana three-nucleon potential. The isospin state
have been included in the calculations as well as the - mass difference.
The H-He mass difference has been evaluated through the charge
dependent terms explicitly included in the two-body potential. The calculations
have been performed using two different methods: the solution of the Faddeev
equations in momentum space and the expansion on the correlated hyperspherical
harmonic basis. The results are in agreement within 0.1% and can be used as
benchmark tests. Results for the CD-Bonn interaction are also presented. It is
shown that the H and He binding energy difference can be predicted
model independently.Comment: 5 pages REVTeX 4, 1 figures, 6 table
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