Optic disk vasculitis

A 44-year-old woman developed progressive loss of vision associated initially with a swollen optic disk, and later with optic atrophy and a diffuse retinal vasculopathy, which caused extensive retinal hemorrhagagic. Histopathologic examination showed hemorrhagagic infarction of the retina, as well as infarction of the anterior optic nerve. In the optic nerve, the central retinal vessels showed extensive phlebitis and occlusion of many small arterioles.     

Chemical depolymerization of oil shale

The chemical structure of the organic matter from Krassava oil shale has been investigated by means of chemical degradation with metallic sodium in liquid ammonia and with phenol in the presence p-toluenesulphonic acid. The former reaction yielded 20 wt% of pyridine-soluble material and the latter ≈ 65 wt%. Extensive depolymerization of the oil shale was achieved by a combination of both methods in which case the solubility of the organic matter was increased to 85–95 wt%. The characterization of soluble and insoluble products by pyrolysis g.c. and elemental analysis indicated that aliphatic chains were prevalent in the organic matter of the Krassava oil shale.     

Clinicopathologic correlations in diabetic retinopathy. I. Histology and fluorescein angiography of microaneurysms

A patient with adult-onset diabetes mellitus was referred with a diagnosis of malignant melanoma of the choroid of the left eye. A nonproliferative type of diabetic retinopathy was present, which was studied and documented by stereoscopic fundus photographs and fluorescein angiograms. Following enucleation, the microangiopathies were correlated histologically, using the retinal trypsin digest technique. Four types of microaneurysms were seen histologically that were believed to represent stages in the development of this lesion. Most thin-walled aneurysms tightly packed with erythrocytes did not fluoresce. Aneurysms that were hypercellular and those with thick walls showed early and late fluorescence. Intraretinal microvascular abnormalities were hypercellular dilated channels. Those that take origin from terminal arterioles are believed to represent attempts at neovascularization.     

Specular, diffuse, and polarized imagery of an oat canopy

Light, polarized by specular reflection, has been found to be an important part of the light scattered by several measured plant canopies. The authors investigate for one canopy the relative importance of specularly reflected sunlight, specularly reflected light from other sources including skylight, and diffusely upwelling light. Polarization images are used to gain increased understanding of the radiation transfer process in a plant canopy. Analysis of the results suggests that properly analyzed polarized remotely sensed data, acquired under specific atmospheric conditions by a specially designed sensor, potentially provide measures of physiological and morphological states of plants in a canopy