Relativistic Multiple Scattering Theory and the Relativistic Impulse Approximation

It is shown that a relativistic multiple scattering theory for hadron-nucleus scattering can be consistently formulated in four-dimensions in the context of meson exchange. We give a multiple scattering series for the optical potential and discuss the differences between the relativistic and non-relativistic versions. We develop the relativistic multiple scattering series by separating out the one boson exchange term from the rest of the Feynman series. However this particular separation is not absolutely necessary and we discuss how to include other terms. We then show how to make a three-dimensional reduction for hadron-nucleus scattering calculations and we find that the relative energy prescription used in the elastic scattering equation should be consistent with the one used in the free two-body t-matrix involved in the optical potential. We also discuss what assumptions are involved in making a Dirac Relativistic Impulse Approximation (RIA).Comment: 20 pages, 9 figures, Accepted for publication in Journal of Physics

On the mechanism of inactivation of antibody activity by cobalt-60 gamma radiation-I

Experimentally determined relationships between 60Co radiation dose and inactivation of combining activity of anti-PAB indicated that a relatively large number of reactions were associated with inactivation. A progressive increase in gross molecular disorganization with increasing radiation dose was indicated by a change in viscosity. Some degree of molecular rearrangement was also suggested by an increased availability of an average of two to three disulphide bonds for reduction after irradiation in presence of urea. The molecular rearrangement suggested by viscosity and disulphide analysis is probably related to the inactivation process, rather than to mere secondary radiation-induced damage of material already inactivated, since, they were first measurable at doses of 7 x 104 and 15 x 104 rads, respectively, as compared to D37 of 35 x 104 rads.The irradiated material was found to contain, in addition to a grossly denaturated fraction insoluble at low ionic strength, some subtly denaturated fractions. These fractions were demonstrated by such sensitive techniques as elimination patterns in rabbits and rates of tryptic hydrolysis. Augmented inactivation above, that resulting from irradiation alone, was demonstrated to follow mild post-irradiation heat treatment (40-41[deg] for 3 hr). This increased heat-induced inactivation was not accompanied by detectable changes in viscosity or in the number of disulphide bonds available for reduction. It appeared to relate to the presence of molecular species, in irradiated antibody solution, that had undergone almost complete disorganization of combining sites, since stabilization of combining site by p-iodobenzoic added before heat treatment could not protect against the additional loss of activity. The degree of inactivation relating to the alternative possibility of free radical reactions with a critical group(s) in the combining site was evaluated by blocking experiments with specific haptens and was found to be insignificant.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33451/1/0000854.pd

Automatización del generador eléctrico del Hospital de Magdalena

Sumario: Estudio en planta - El dispositivo de conmutación - Automatización del generador - Manuales de instrucciones - Conclusiones.Facultad de Ingenierí

Automatización del generador eléctrico del Hospital de Magdalena

Sumario: Estudio en planta - El dispositivo de conmutación - Automatización del generador - Manuales de instrucciones - Conclusiones.Facultad de Ingenierí

El líder y la empresa en crisis

Fil: Fleicher, Gregorio Julio. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Buenos Aires, Argentina

Discovering Spotify A Thematic Introduction

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