Chylous effusions revisited

Varying terms and criteria have been used in the veterinary literature to characterize milky opaque pleural effusions through the years. This article addresses ideas widely repeated in the veterinary and human literature upon which time, experience, diagnostic techniques, experimental data, and improved understanding of pathogenesis have cast doubt. Topics discussed include terminology, pathogenesis of chylous and pseudochylous effusions, criteria for differentiation of chylous from pseudochylous effusions, and clinicopathologic changes associated with drainage of chylous effusions.     

Structure of solidified colloidal array laser filters studied by cryogenic transmission electron microscopy

Ordered arrays of charged uniform colloidal polystyrene particles in solution form a single-wavelength laser filter that is transparent to other wavelengths. A usable filter was prepared by solidification within an acrylamide-methylene-bisacrylamide gel. The rejection wavelength of the colloidal array filter changes with gel composition. Cryogenic transmission electron microscopy of two gel formulations shows that the colloidal array filter is composed of AAA stacking of close-packed planes. Excellent agreement is found between the layer spacings measured and those predicted from the rejection wavelengths.