Solution and Asymptotic Behavior for a Nonlocal Coupled System of Reaction-Diffusion

This paper concerns with existence, uniqueness and asymptotic behavior of the solutions for a nonlocal coupled system of reaction-diffusion. We prove the existence and uniqueness of weak solutions by the Faedo-Galerkin method and exponential decay of solutions by the classic energy method. We improve the results obtained by Chipot-Lovato and Menezes for coupled systems. A numerical scheme is presented

Influence of season of birth, sex and paternal line on growth performance and carcass traits in pigs

Participants in the pig production industry focus on feed and feed additives to improve growth performance and meat quality of pigs. Consequently, the Rural Development Administration of the Republic of Korea produced a new paternal line to improve economic traits in pigs. However, there is an absence of information on pig traits with regard to season and sex, and a comparison between the new paternal line and past paternal lines. Therefore, the authors conducted this study to investigate the influence of season of birth, sex and paternal line on growth performance and carcass traits in pigs. A total of 2888 piglets ((Landrace × Yorkshire) × Darby Duroc (DD) or Chookjin Duroc (CD)) with an average age of three weeks were tested for 22 weeks during the four season of the year (spring 608 piglets, summer 404 piglets, autumn 576 piglets and winter 1300 piglets). The bodyweights (BW) of individual pig were recorded, and feed consumption was recorded at weeks 2, 12 and 22, to determine growth performance. At reaching market weight, backfat thickness was determined at the last rib area. Meat was graded according to the criteria of the slaughterhouse. There were no significant differences in growth performance and carcass traits between sexes. The CD line crossbred pig had a significant higher BW at 16 weeks, and higher carcass trait values at 22 weeks than the DD line. During weeks 8 to 16 the CD line crossbred pigs showed a tendency of an increased average daily gain (ADG) and gain : feed (G : F) ratio compared with the DD line. Furthermore, pigs born in spring had significant lower ADG, average daily feed intake (ADFI) and carcass trait values than born in the other seasons. In conclusion, the new paternal line (Chookjin Duroc) improved growth performance and carcass traits compare with the DD line.Keywords: sex, growth, terminal sire, meat quality, backfat thicknes

Study of heterogeneous nucleation of eutectic Si in high-purity Al-Si alloys with Sr addition

The official published version can be accessed from the link below - Copyright @ 2010 The Minerals, Metals & Materials Society and ASM InternationalAl-5 wt pct Si master-alloys with controlled Sr and/or P addition/s were produced using super purity Al 99.99 wt pct and Si 99.999 wt pct materials in an arc melter. The master-alloy was melt-spun resulting in the production of thin ribbons. The Al matrix of the ribbons contained entrained Al-Si eutectic droplets that were subsequently investigated. Differential scanning calorimetry, thermodynamic calculations, and transmission electron microscopy techniques were employed to examine the effect of the Sr and P additions on eutectic undercoolings and nucleation phenomenon. Results indicate that, unlike P, Sr does not promote nucleation. Increasing Sr additions depressed the eutectic nucleation temperature. This may be a result of the formation of a Sr phase that could consume or detrimentally affect potent AlP nucleation sites.This work is financially supported by the Higher Education Commission of Pakistan and managerially supported from the OAD

Inelastic J/ψJ/\psi production in polarized photon-hadron collisions

Presented here is a calculation of inelastic $J/\psi$ production in polarized photon-hadron collisions under the framework of NRQCD factorization formalism. We consider the photoproduction of \jpsi in the energy range relevant to HERA. The Weizs\"acker-Williams approximation is adopted in the evaluation of the cross sections for $ep$ collisions. We found that this process can give another independent test for the color-octet mechanism, and the different features for the two color-octet processes may provide further informations on the mechanism for inelastic \jpsi photoproduction. And the discrepancy on the production asymmetry $A$ between various sets of polarized gluon distribution functions is also found to be distinctive.Comment: 14pages, 6 PS figure

Certain subclasses of multivalent functions defined by new multiplier transformations

In the present paper the new multiplier transformations \mathrm{{\mathcal{J}% }}_{p}^{\delta }(\lambda ,\mu ,l) (\delta ,l\geq 0,\;\lambda \geq \mu \geq 0;\;p\in \mathrm{% }%\mathbb{N} )} of multivalent functions is defined. Making use of the operator $\mathrm{{\mathcal{J}}}_{p}^{\delta }(\lambda ,\mu ,l),$ two new subclasses $\mathcal{P}_{\lambda ,\mu ,l}^{\delta }(A,B;\sigma ,p)$ and $\widetilde{\mathcal{P}}_{\lambda ,\mu ,l}^{\delta }(A,B;\sigma ,p)$\textbf{\ }of multivalent analytic functions are introduced and investigated in the open unit disk. Some interesting relations and characteristics such as inclusion relationships, neighborhoods, partial sums, some applications of fractional calculus and quasi-convolution properties of functions belonging to each of these subclasses $\mathcal{P}_{\lambda ,\mu ,l}^{\delta }(A,B;\sigma ,p)$ and $\widetilde{\mathcal{P}}_{\lambda ,\mu ,l}^{\delta }(A,B;\sigma ,p)$ are investigated. Relevant connections of the definitions and results presented in this paper with those obtained in several earlier works on the subject are also pointed out

Cosmological viability of f(R)-gravity as an ideal fluid and its compatibility with a matter dominated phase

We show that f(R)-gravity can, in general, give rise to cosmological viable models compatible with a matter-dominated epoch evolving into a late accelerated phase. We discuss the various representations of f(R)-gravity as an ideal fluid or a scalar-tensor gravity theory, taking into account conformal transformations. We point out that mathematical equivalence does not correspond, in several cases, to the physical equivalence of Jordan frame and Einstein frame. Finally, we show that wide classes of f(R)-gravity models, including matter and accelerated phases, can be phenomenologically reconstructed by means of observational data. In principle, any popular quintessence models could be "reframed" as an f(R)-gravity model.Comment: 11 pages, 1 figur

Feeding and Distribution of Porosity in Cast Al-Si Alloys as Function of Alloy Composition and Modification

Unmodified, Na-modified, and Sr-modified castings of Al-7 pct Si and Al-12.5 pct Si alloys were cast in molds in which it was possible to create different cooling conditions. It is shown how solidification influences the distribution of porosity at the surface and the center of the castings as a function of modification and Si content in sand- and chill-cast samples. Eutectic modification, Si content, and cooling conditions have a great impact on the distribution of porosity. Unmodified and Na-modified castings are more easily fed with porosity tending to congregate near the centerline of the casting, while Sr-modified castings solidify in a mushy manner that creates a more homogeneous distribution of porosity in the casting. The amount of porosity was highest in the Sr-modified alloys, lower in the Na-modified alloys, and lowest in the unmodified alloys. The size of the porosity-free layer and the effectiveness of the feeders were greater in the castings made with the steel chills due to the increased thermal gradients and consequent increase in the directionality of solidification

Mean-atom-trajectory model for the velocity autocorrelation function of monatomic liquids

We present a model for the motion of an average atom in a liquid or supercooled liquid state and apply it to calculations of the velocity autocorrelation function $Z(t)$ and diffusion coefficient $D$. The model trajectory consists of oscillations at a distribution of frequencies characteristic of the normal modes of a single potential valley, interspersed with position- and velocity-conserving transits to similar adjacent valleys. The resulting predictions for $Z(t)$ and $D$ agree remarkably well with MD simulations of Na at up to almost three times its melting temperature. Two independent processes in the model relax velocity autocorrelations: (a) dephasing due to the presence of many frequency components, which operates at all temperatures but which produces no diffusion, and (b) the transit process, which increases with increasing temperature and which produces diffusion. Because the model provides a single-atom trajectory in real space and time, including transits, it may be used to calculate all single-atom correlation functions.Comment: LaTeX, 8 figs. This is an updated version of cond-mat/0002057 and cond-mat/0002058 combined Minor changes made to coincide with published versio

MHV Rules for Higgs Plus Multi-Gluon Amplitudes

We use tree-level perturbation theory to show how non-supersymmetric one-loop scattering amplitudes for a Higgs boson plus an arbitrary number of partons can be constructed, in the limit of a heavy top quark, from a generalization of the scalar graph approach of Cachazo, Svrcek and Witten. The Higgs boson couples to gluons through a top quark loop which generates, for large top mass, a dimension-5 operator H tr G^2. This effective interaction leads to amplitudes which cannot be described by the standard MHV rules; for example, amplitudes where all of the gluons have positive helicity. We split the effective interaction into the sum of two terms, one holomorphic (selfdual) and one anti-holomorphic (anti-selfdual). The holomorphic interactions give a new set of MHV vertices -- identical in form to those of pure gauge theory, except for momentum conservation -- that can be combined with pure gauge theory MHV vertices to produce a tower of amplitudes with more than two negative helicities. Similarly, the anti-holomorphic interactions give anti-MHV vertices that can be combined with pure gauge theory anti-MHV vertices to produce a tower of amplitudes with more than two positive helicities. A Higgs boson amplitude is the sum of one MHV-tower amplitude and one anti-MHV-tower amplitude. We present all MHV-tower amplitudes with up to four negative-helicity gluons and any number of positive-helicity gluons (NNMHV). These rules reproduce all of the available analytic formulae for Higgs + n-gluon scattering (n<=5) at tree level, in some cases yielding considerably shorter expressions.Comment: 34 pages, 8 figures; v2, references correcte