Feasibility of Transdermal, Needleless Injections for Prevention of Pork Carcass Defects

A needle-free transdermal injection device was evaluated for effectiveness of vaccine delivery and for injection site lesions. A total of 96 pigs were vaccinated for pseudorabies virus (PRV) and Mycoplasma hyopneumoniae (M.hyo.). Pigs were divided into three groups; the first group served as unvaccinated controls, the second group was vaccinated with conventional hypodermic needles, and a third group was vaccinated with a needle-free, air-powered injection device. Pigs were tattooed on the neck to mark the injection sites. Blood samples were collected from the pigs at 11−13 days and 23−25 days after injection, and the serological response was measured. Injection sites were collected at slaughter and dissected to evaluate tissue damage. The results showed that both injection methods produced similar serological responses in the vaccinated pigs and both were significantly greater than the unvaccinated controls. The injection site examinations have shown no lesions in any of the pigs. The results show the needle-free, transdermal injection device to be effective and safe. Elimination of needles will prevent residual needle fragments in carcasses and associated carcass defects from injection site lesion

A Physical Model of Lyman Alpha Emitters

We present a simple physical model for populating dark matter halos with Lyman Alpha Emiiters(LAEs) and predict the physical properties of LAEs at z~3-7. The central tenet of this model is that the Ly-alpha luminosity is proportional to the star formation rate (SFR) which is directly related to the halo mass accretion rate. The only free parameter in our model is then the star-formation efficiency (SFE). An efficiency of 2.5% provides the best-fit to the Ly-alpha luminosity function (LF) at redshift z=3.1, and we use this SFE to construct Ly-alpha LFs at other redshifts. Our model reproduce the Ly-alpha LFs, stellar ages, SFR ~1-10; Msun/yr, stellar masses ~ 10^7-10^8 Msun and the clustering properties of LAEs at z~3-7. We find the spatial correlation lengths ro ~ 3-6 Mpc/h, in agreement with the observations. Finally, we estimate the field-to-field variation ~ 30% for current volume and flux limited surveys, again consistent with observations. Our results suggest that the star formation, and hence Ly-alpha emission in LAEs is powered by the accretion of new material, and that the physical properties of LAEs do not evolve significantly over a wide range of redshifts. Relating the accreted mass, rather than the total mass of halos, to the Ly-alpha luminosity of LAEs naturally gives rise to the duty cycle of LAEs.Comment: Published in Ap

Analyzing Mean Transport Equations of Turbulence and Linear Disturbances in Decaying Flows

The decay of laminar disturbances and turbulence in mean shear-free flows is studied. In laminar flows, such disturbances are linear superpositions of modes governed by the Orr-Sommerfeld equation. In turbulent flows, disturbances are described through transport equations for representative mean quantities. The link between a description based on a deterministic evolution equation and a probability-based mean transport equation is established. Because an uncertainty in initial conditions exists in the laminar as well as the turbulent regime, a probability distribution must be defined even in the laminar case. Using this probability distribution, it is shown that the exponential decay of the linear modes in the laminar regime can be related to a power law decay of both the (ensemble) mean disturbance kinetic energy and the dissipation rate. The evolution of these mean disturbance quantities is then described by transport equations similar to those for the corresponding turbulent decaying flow

Chiral Loops and Ghost States in the Quenched Scalar Propagator

The scalar, isovector meson propagator is analyzed in quenched QCD, using the MQA pole-shifting ansatz to study the chiral limit. In addition to the expected short-range exponential falloff characteristic of a heavy scalar meson, the propagator also exhibits a longer-range, negative metric contribution which becomes pronounced for smaller quark masses. We show that this is a quenched chiral loop effect associated with the anomalous structure of the $\eta '$ propagator in quenched QCD. Both the time dependence and the quark mass dependence of this effect are well-described by a chiral loop diagram corresponding to an $\eta '- \pi$ intermediate state, which is light and effectively of negative norm in the quenched approximation. The relevant parameters of the effective Lagrangian describing the scalar sector of the quenched theory are determined.Comment: 29 pages, 10 figures, Late

The Temporally Filtered Navier-Stokes Equations: Propertes of the Residual Stress

Recent interest in the development of a unifying framework among direct numerical simulations, large-eddy simulations, and statistically averaged formulations of the Navier-Stokes equations, provides the motivation for the present paper. Toward that goal, the properties of the residual (subgrid-scale) stress of the temporally filtered Navier-Stokes equations are carefully examined. This includes the frame-invariance properties of the filtered equations and the resulting residual stress. Causal time-domain filters, parametrized by a temporal filter width 0infinity, the residual stress is equivalent to the long-time averaged stress, and the Reynolds-averaged Navier-Stokes equations are recovered from the temporally filtered equations. The predicted behavior at the asymptotic limits of filter width is further validated by numerical simulations of the temporally filtered forced, viscous Burger\u27s equation. Finally, finite filter widths are also considered, and both a priori and a posteriori analyses of temporal similarity and temporal approximate deconvolution models of the residual stress are conducted for the model problem

Finite size corrections in massive Thirring model

We calculate for the first time the finite size corrections in the massive Thirring model. This is done by numerically solving the equations of periodic boundary conditions of the Bethe ansatz solution. It is found that the corresponding central charge extracted from the $1/L$ term is around 0.4 for the coupling constant of ${g_0}=-{\pi\over 4}$ and decreases down to zero when ${g_0}=-{\pi\over{3}}$. This is quite different from the predicted central charge of the sine-Gordon model.Comment: 8 pages, Latex, 2 figure

The infrared behaviour of the static potential in perturbative QCD

The definition of the quark-antiquark static potential is given within an effective field theory framework. The leading infrared divergences of the static singlet potential in perturbation theory are explicitly calculated.Comment: 4 pages, 2 postscript figures, uses revtex.st

Measurement of hybrid content of heavy quarkonia using lattice NRQCD

Using lowest-order lattice NRQCD to create heavy meson propagators and applying the spin-dependent interaction, $c_B^{} \frac{-g}{2m_q}\vec\sigma\cdot\vec{B}$, at varying intermediate time slices, we compute the off-diagonal matrix element of the Hamiltonian for the quarkonium-hybrid two-state system. Thus far, we have results for one set of quenched lattices with an interpolation in quark mass to match the bottomonium spectrum. After diagonalization of the two-state Hamiltonian, we find the ground state of the $\Upsilon$ to show a $0.0035(1)c_B^2$ (with $c_B^2 \sim 1.5-3.1$) probability admixture of hybrid, $|b\bar{b}g>$.Comment: 11 pages, 4 figures, to appear in Phys Rev

Experimental Model for Porcine Circovirus and Porcine Parvovirus Coinfection of Specific-Pathogen-Free Pigs

Porcine parvovirus (PPV) coinfection has been shown to increase the incidence and severity of porcine circovirus 2 (PCV2) associated disease in gnotobiotic and in colostrum-deprived pigs. PPV and PCV2 coinfection is also common in the grow-finish pigs in the field today. The objectives of this study were to determine the interactions between PCV2 and PPV in conventional SPF pigs and to determine whether PPV vaccine has an effect on the coinfection. Seventy-two, 6-week-old conventional pigs were inoculated either with PCV2, PPV, both PCV2 and PPV, or sham-inoculated. Before inoculation, 56 pigs were vaccinated twice with a PPV killed-virus vaccine. Clinical signs due to postweaning multisystemic wasting syndrome (PMWS) (fever, respiratory disease, jaundice, weight loss) were seen in both coinfected groups, vaccinated as well as nonvaccinated. The majority of pigs in the PCV2, and in the PCV2/PPV-inoculated groups had mild-to-severe lymphoid depletion with histiocytic replacement of follicles, and mild lymphohistiocytic interstitial pneumonia. The majority of pigs in the PCV2/PPV-coinfected groups also had mild-to-severe lymphoplasmacytic interstitial nephritis and hepatitis. There were no statistical differences between the two coinfected groups (vaccinated and non-vaccinated) in terms of clinical disease, and macroscopic and microscopic lesions. The results indicated that PPV and PCV2 coinfection resulted in increased severity of clinical disease and lymphoid lesions typical of PMWS and that a PPV-vaccination was not able to prevent PMWS in PCV2/PPV-coinfected pigs