Hypochromicity in red blood cells: an experimental and theoretical investigation

Multiwavelength UV-visible transmission spectrophotometry is a useful tool for the examination of micron-size particle suspensions in the context of particle size and chemical composition. This paper reports the reliability of this method to characterize the spectra of purified red blood cells both in their physiological state and with modified hemoglobin content. Previous studies have suggested the contribution of hypochromism on the particle spectra caused by the close electronic interaction of the encapsulated chromophores. Our research shows, however, that this perceived hypochromism can be accounted for by considering two important issues: the acceptance angle of the instrument and the combined scattering and absorption effect of light on the particles. In order to establish these ideas, spectral analysis was performed on purified and modified red cells where the latter was accomplished with a modified hypotonic shock protocol that altered the hemoglobin concentration within the cells. Moreover, the Mie theory was used to successfully simulate the spectral features and trends of the red cells. With this combination of experimental and theoretical exploration, definition of hypochromism has been extended to two subcategories

LASER SOURCE OF POLARIZED PROTONS

Dans cet article sont présentés des résultats du developpement de la source des protons polarisés. Actuellement dans cette source on a obtenu 200 μA l'intensité du faisceau des protons polarisés avec la polarisation 65±5%.The results of the development of a laser source of polarized protons are presented. Today in this source 200 μA pulse intensity of polarized protons is obtained with polarization 65±5%