1,283 research outputs found
Benefits of a commercial solid-state fermentation (SSF) product on growth performance, feed efficiency and gut morphology of juvenile Nile tilapia (Oreochromis niloticus) fed different UK lupin meal cultivars
A nutritional investigation was conducted to determine whether growth performance, feed efficiency and midgut morphology of Nile tilapia is affected by United Kingdom cultivars of Yellow Lupin (Control, Y) (YLC) or Blue Lupin (Control, B) (BLC) inclusions compared to the addition of a commercial solid-state fermentation product (SSF) in separate dietary treatments for both lupin cultivars (YLS and BLS). After 49 days of feeding, tilapia receiving SSF supplemented diets (YLS & BLS) exhibited significantly greater weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER) and condition factor (K) compared to YLC or BLC without solid state fermentation. SSF inclusion exhibited significantly improving of enterocyte height within both the first and second half of the experiment (P .05); although a potential response over time was apparent in the YLS group. Enterocyte microvilli were significantly wider in fish fed YLC diets (P < .05), whilst they were significantly longer in the BLC control compared to the YLC control (P < .05). Microvilli lengths of fish fed YLS were comparable to those receiving BLC diets and close to being significantly longer than those fed YLC alone (P = .06). Overall, BLC appeared to perform superiorly to YLC; whilst SSF inclusion promoted some desirable production parameters, seemingly most effectively in the YLC diet
Dietary nucleotides enhance growth performance, feed efficiency and intestinal functional topography in European Seabass ( Dicentrarchus labrax )
Nucleotides, nucleosides and nucleic acids (NU) have many critical functions in supporting life and increasing evidence suggests that exogenous supply can benefit the health of mammals and fish. For these reasons, a 6âweek feeding trial was conducted on juvenile European seabass (Dicentrarchus labrax) with diets containing 0%, 0.15% and 0.3% inclusion of a NU mixture (LaltideÂź) derived from the yeast Saccharomyces cerevisiae. At the end of the study no significant differences were found in fish performance, although a tendency towards better performance was indicated in fish fed the Nu0.3 diet. In relation to histological assessment, a significantly greater perimeter ratio; internal to outer (IP/OP) was observed in the posterior intestine of fish fed supplemental NU. Microvilli heights in the posterior intestine were also shown to be significantly promoted in fish fed NU diets (p 0.05). Overall, this study indicates that orally administered NU may be effective promoters of gut functional topography with marginal associated improvements to fish performance. Nonetheless, longer exposure and/or commercial scale application, and in diets that were challenging in use of high inclusion levels of plant byâproducts would potentially amplify improvements in production characteristics, in turn benefiting fish culturists
Interactions, Distribution of Pinning Energies, and Transport in the Bose Glass Phase of Vortices in Superconductors
We study the ground state and low energy excitations of vortices pinned to
columnar defects in superconductors, taking into account the long--range
interaction between the fluxons. We consider the ``underfilled'' situation in
the Bose glass phase, where each flux line is attached to one of the defects,
while some pins remain unoccupied. By exploiting an analogy with disordered
semiconductors, we calculate the spatial configurations in the ground state, as
well as the distribution of pinning energies, using a zero--temperature Monte
Carlo algorithm minimizing the total energy with respect to all possible
one--vortex transfers. Intervortex repulsion leads to strong correlations
whenever the London penetration depth exceeds the fluxon spacing. A pronounced
peak appears in the static structure factor for low filling fractions . Interactions lead to a broad Coulomb gap in the distribution of
pinning energies near the chemical potential , separating
the occupied and empty pins. The vanishing of at leads to a
considerable reduction of variable--range hopping vortex transport by
correlated flux line pinning.Comment: 16 pages (twocolumn), revtex, 16 figures not appended, please contact
[email protected]
On The Problem of Particle Production in c=1 Matrix Model
We reconsider and analyze in detail the problem of particle production in the
time dependent background of matrix model where the Fermi sea drains away
at late time. In addition to the moving mirror method, which has already been
discussed in hep-th/0403169 and hep-th/0403275, we describe yet another method
of computing the Bogolubov coefficients which gives the same result. We
emphasize that these Bogolubov coefficients are approximately correct for small
value of the deformation parameter.
We also study the time evolution of the collective field theory stress-tensor
with a special point-splitting regularization. Our computations go beyond the
approximation of the previous treatments and are valid at large coordinate
distances from the boundary at a finite time and up-to a finite coordinate
distance from the boundary at late time. In this region of validity our
regularization produces a certain singular term that is precisely canceled by
the collective field theory counter term in the present background. The energy
and momentum densities fall off exponentially at large distance from the
boundary to the values corresponding to the static background. This clearly
shows that the radiated energy reaches the asymptotic region signaling the
space-time decay.Comment: 37 pages, 5 figures. Section 6 is modified to clarify main
accomplishments of the paper including a discussion comparing stress-tensor
analysis with those preexisted in literature. Other modifications include
minor changes in the text and addition of one reference. Version accepted for
publication in JHE
Staggered versus overlap fermions: a study in the Schwinger model with
We study the scalar condensate and the topological susceptibility for a
continuous range of quark masses in the Schwinger model with
dynamical flavors, using both the overlap and the staggered discretization. At
finite lattice spacing the differences between the two formulations become
rather dramatic near the chiral limit, but they get severely reduced, at the
coupling considered, after a few smearing steps.Comment: 15 pages, 7 figures, v2: 1 ref corrected, minor change
Static quantities of the W boson in the SU_L(3) X U_X(1) model with right-handed neutrinos
The static electromagnetic properties of the boson, and
, are calculated in the SU_L(3)} \times U_X(1) model with
right-handed neutrinos. The new contributions from this model arise from the
gauge and scalar sectors. In the gauge sector there is a new contribution from
a complex neutral gauge boson and a singly-charged gauge boson .
The mass of these gauge bosons, called bileptons, is expected to be in the
range of a few hundreds of GeV according to the current bounds from
experimental data. If the bilepton masses are of the order of 200 GeV, the size
of their contribution is similar to that obtained in other weakly coupled
theories. However the contributions to both and are
negligible for very heavy or degenerate bileptons. As for the scalar sector, an
scenario is examined in which the contribution to the form factors is
identical to that of a two-Higgs-doublet model. It is found that this sector
would not give large corrections to and .Comment: New material included. Final version to apppear in Physical Review
Neutrino Masses with "Zero Sum" Condition:
It is well known that the neutrino mass matrix contains more parameters than
experimentalists can hope to measure in the foreseeable future even if we
impose CP invariance. Thus, various authors have proposed ansatzes to restrict
the form of the neutrino mass matrix further. Here we propose that ; this ``zero sum'' condition can occur in certain
class of models, such as models whose neutrino mass matrix can be expressed as
commutator of two matrices. With this condition, the absolute neutrino mass can
be obtained in terms of the mass-squared differences. When combined with the
accumulated experimental data this condition predicts two types of mass
hierarchies, with one of them characterized by eV, and the other by eV and eV. The mass ranges
predicted is just below the cosmological upper bound of 0.23 eV from recent
WMAP data and can be probed in the near future. We also point out some
implications for direct laboratory measurement of neutrino masses, and the
neutrino mass matrix.Comment: Latex 12 pages. No figures. New references adde
On the vanishing electron-mass limit in plasma hydrodynamics in unbounded media
We consider the zero-electron-mass limit for the Navier-Stokes-Poisson system
in unbounded spatial domains. Assuming smallness of the viscosity coefficient
and ill-prepared initial data, we show that the asymptotic limit is represented
by the incompressible Navier-Stokes system, with a Brinkman damping, in the
case when viscosity is proportional to the electron-mass, and by the
incompressible Euler system provided the viscosity is dominated by the electron
mass. The proof is based on the RAGE theorem and dispersive estimates for
acoustic waves, and on the concept of suitable weak solutions for the
compressible Navier-Stokes system
The Concise Guide to Pharmacology 2015/16: Transporters
The Concise Guide to PHARMACOLOGY 2015/16 provides concise overviews of the key properties of over 1750 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. The full contents can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.13355/full. G protein-coupled receptors are one of the eight major pharmacological targets into which the Guide is divided, with the others being: G protein-coupled receptors, ligand-gated ion channels, voltage-gated ion channels, other ion channels, nuclear hormone receptors, catalytic receptors and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The Concise Guide is published in landscape format in order to facilitate comparison of related targets. It is a condensed version of material contemporary to late 2015, which is presented in greater detail and constantly updated on the website www.guidetopharmacology.org, superseding data presented in the previous Guides to Receptors & Channels and the Concise Guide to PHARMACOLOGY 2013/14. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and GRAC and provides a permanent, citable, point-in-time record that will survive database update
Complex Langevin: Etiology and Diagnostics of its Main Problem
The complex Langevin method is a leading candidate for solving the so-called
sign problem occurring in various physical situations. Its most vexing problem
is that in some cases it produces `convergence to the wrong limit'. In the
first part of the paper we go through the formal justification of the method,
identify points at which it may fail and identify a necessary and sufficient
criterion for correctness. This criterion would, however, require checking
infinitely many identities, and therefore is somewhat academic. We propose
instead a truncation to the check of a few identities; this still gives a
necessary criterion, but a priori it is not clear whether it remains
sufficient. In the second part we carry out a detailed study of two toy models:
first we identify the reasons why in some cases the method fails, second we
test the efficiency of the truncated criterion and find that it works perfectly
at least in the toy models studied.Comment: 39 pages, 15 figures; typos corrected and reference adde
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