Gauging the spectator equations

We show how to derive relativistic, unitary, gauge invariant, and charge conserving three-dimensional scattering equations for a system of hadrons interacting with an electromagnetic field. In the method proposed, the spectator equations describing the strong interactions of the hadrons are gauged using our recently introduced gauging of equations method. A key ingredient in our model is the on-mass-shell particle propagator. We discuss how to gauge this on-mass-shell propagator so that both the Ward-Takahashi and Ward identities are satisfied. We then demonstrate our gauging procedure by deriving the gauge-invariant three-dimensional expression for the deuteron photodisintegration amplitude within the spectator approach.Comment: 17 pages, REVTeX, epsf, 1 Postscript figur

Neutrino-Oxygen CC0π\pi scattering in the SuSAv2-MEC model

We present the predictions of the SuSAv2-MEC model for the double differential charged-current muonic neutrino (antineutrino) cross section on water for the T2K neutrino (antineutrino) beam. We validate our model by comparing with the available inclusive electron scattering data on oxygen and compare our predictions with the recent T2K $\nu_\mu$-$^{16}$O data, finding good agreement at all kinematics. We show that the results are very similar to those obtained for $\nu_\mu-^{12}$C scattering, except at low energies, and we comment on the origin of this difference. A factorized spectral function model of $^{16}$O is also included for purposes of comparison.Comment: 28 pages, 10 figures, JLAB-THY-17-2586. Version 2 accepted for publication in Journal of Physics G: Nucl. Part. Phy

Evaluación de la función adrenal en perros

En 30 perros sanos, hemos estudiado los niveles de cortisol plasmático antes y después de la administración de hormona adrenocórticotropa (ACTH sintético, vía i.m.) y de dexametasona (dosis de 0,01 y 0,02 mg/Kg p.v., vía i.v.), Las pruebas se iniciaron siempre antes de las 10 horas de la mañana y las determinaciones de cortisol plasmático se evaluaron mediante técnicas de RIA. En nuestras condiciones de trabajo, hemos encontrado unos niveles basales de cortisol cuyo rango va de 0,17 a 7,95 ug/ dl. Se ha observado que, en perros sin sintomatología adrenal y con perfiles hematológicos y bioquímicos normales, la prueba de estimulación con ACTH exógeno, a las dos horas de su administración, es capaz de discriminar como animales sanos el 76,7% de los individuos (23 animales), dando falsos resultados positivos en el 10% (3 animales) y una estimulación baja en el U)% (4 animales). La prueba con dexametasona (0,01 mg/Kg p.v.), a las 8 horas de su aplicación, sólo es capaz de ejercer efecto inhibitorio en el 40% de los casos (12 individuos); pero cuando se incrementa la dosis al doble (dexametasona 0,02 mg/Kg p.v.) se 49 obtienen los mejores resultados de toda la experiencia porque se produce el efecto supresor esperado en el 96,7% de los individuos (29 animales).Thirty healty dogs uiere evaluated for plasma cortisol values before and after adrenocorticotrophic hormone (ACm, administered i.m.) and low dose dexamethasone (0.01 and 0.02 mglKgp.v. administered i.u.). The assays started always before 10 hour A.M.} and cortisol plasma concentrations were determined by RIA. In our laboratory we have obserued the normal baseline morning cortisol concentration was between 0.17 and 7.95 ¡..tgldl. ACTH-estimulation test wasfound abnormal bypereponse in 10% (J animals), anormallow stimulation in 11.1% (a dogs) and a expected byperreponse in 76.7% (23) ofthe normal dogs.Dexamethasone-screening test (0.01 mg/Kgp.v.) bring us supressed effect in 40% (12 animals). But wefound the best reliable results when screening test was applied with 0.02 mg/Kgp.v. dexamethasone dose. the suppressed especting effect wasfound in 06. 7% (29 dogs)

THE ROLE OF PRODUCT ATTRIBUTES IN THE AGRICULTURAL NEGOTIATIONS

Marketing, International Relations/Trade,

RPA quasi-elastic responses in infinite and finite nuclear systems

Quasi-elastic responses in nuclear matter and in $^{12}$C and $^{40}$Ca nuclei are calculated in ring approximation to investigate the finite size effects on the electromagnetic quasi-elastic responses. A method to simulate these effects in infinite systems calculations is proposed. The sensitivity of the results to the various terms of the residual interaction is studied. The results of nuclear matter RPA calculations are compared with those obtained in ring approximation to evidence the importance of the exchange terms.Comment: 14 pages, 8 figure

On the Structure of Measurement Noise in Eye-Tracking

Past research has discovered fractal structure in eye movement variability and interpreted this result as having theoretical ramifications. No research has, however, investigated how properties of the eye-tracking instrument might affect the structure of measurement varia-bility. The current experiment employed fractal and multifractal methods to investigate whether an eye-tracker produced intrinsic random variation and how features of the data recording procedure affected the structure measurement variability. The results of this experiment revealed that the structure of variation from a fake eye was indeed random and uncorrelated in contrast to the fractal structure from a fixated, real human eye. Moreover, the results demonstrated that data-averaging generally changes the structure of variation, introducing spurious structure into eye movement variability

Origin of Relativistic Effects in the Reaction D(e,e'p)n at GeV Energies

In a series of recent publications, a new approach to the non-relativistic reduction of the electromagnetic current operator in calculations of electro-nuclear reactions has been introduced. In one of these papers, the conjecture that at energies of a few GeV, the bulk of the relativistic effects comes from the current and not from the nuclear dynamics was made, based on the large relativistic effects in the transverse-longitudinal response. Here, we explicitly compare a fully relativistic, manifestly covariant calculation performed with the Gross equation, with a calculation that uses a non-relativistic wave function and a fully relativistic current operator. We find very good agreement up to missing momenta of 400 MeV/c, thus confirming the previous conjecture. We discuss slight deviations in cross sections for higher missing momenta and their possible origin, namely p-wave contributions and off-shell effects.Comment: 25 pages, 11 figure

Herding model and 1/f noise

We provide evidence that for some values of the parameters a simple agent based model, describing herding behavior, yields signals with 1/f power spectral density. We derive a non-linear stochastic differential equation for the ratio of number of agents and show, that it has the form proposed earlier for modeling of 1/f^beta noise with different exponents beta. The non-linear terms in the transition probabilities, quantifying the herding behavior, are crucial to the appearance of 1/f noise. Thus, the herding dynamics can be seen as a microscopic explanation of the proposed non-linear stochastic differential equations generating signals with 1/f^beta spectrum. We also consider the possible feedback of macroscopic state on microscopic transition probabilities strengthening the non-linearity of equations and providing more opportunities in the modeling of processes exhibiting power-law statistics

First-principles investigation of spin polarized conductance in atomic carbon wire

We analyze spin-dependent energetics and conductance for one dimensional (1D) atomic carbon wires consisting of terminal magnetic (Co) and interior nonmagnetic (C) atoms sandwiched between gold electrodes, obtained employing first-principles gradient corrected density functional theory and Landauer's formalism for conductance. Wires containing an even number of interior carbon atoms are found to be acetylenic with sigma-pi bonding patterns, while cumulene structures are seen in wires containing odd number of interior carbon atoms, as a result of strong pi-conjugation. Ground states of carbon wires containing up to 13 C atoms are found to have anti-parallel spin configurations of the two terminal Co atoms, while the 14 C wire has a parallel Co spin configuration in the ground state. The stability of the anti-ferromagnetic state in the wires is ascribed to a super-exchange effect. For the cumulenic wires this effect is constant for all wire lengths. For the acetylenic wires, the super-exchange effect diminishes as the wire length increases, going to zero for the atomic wire containing 14 carbon atoms. Conductance calculations at the zero bias limit show spin-valve behavior, with the parallel Co spin configuration state giving higher conductance than the corresponding anti-parallel state, and a non-monotonic variation of conductance with the length of the wires for both spin configurations.Comment: revtex, 6 pages, 5 figure

Modeling quark-hadron duality in polarization observables

We apply a model for the study of quark-hadron duality in inclusive electron scattering to the calculation of spin observables. The model is based on solving the Dirac equation numerically for a scalar confining linear potential and a vector color Coulomb potential. We qualitatively reproduce the features of quark-hadron duality for all potentials considered, and discuss the onset of scaling and duality for the responses, spin structure functions, and polarization asymmetries. Duality may be applied to gain access to kinematic regions which are hard to access in deep inelastic scattering, namely for $x_{Bj} \to 1$, and we discuss which observables are most suitable for this application of duality