Silt three grades fine, medium and coarse 0.002 mm to 0.006 mm to 0.020 mm to 0.063 mm). In actuality, silt is chemically distinct from clay, and unlike clay, grains of silt are approximately the same size in all dimensions; furthermore, their size ranges overlap. Clays are formed from thin plate-shaped particles held together by electrostatic forces, so present a cohesion. Pure silts are not cohesive. According to the U.S. Department of Agriculture Soil Texture Classification system, the sand–silt distinction is made at the 0.05 mm particle size. The USDA system has been adopted by the Food and Agriculture Organization (FAO).
Granular corneal dystrophy autosome), and only one copy of the gene is sufficient to cause the disorder, when inherited from a parent who has the disorder. The gene TGFBI encodes the protein keratoepithelin. Corneal transplant is not needed except in very severe and late cases. Light sensitivity may be overcome by wearing tinted glassess. Granular corneal dystrophy Granular corneal dystrophy is a slowly progressive corneal dystrophy that most often begins in early childhood. Granular corneal dystrophy has two types: Granular corneal dystrophy is diagnosed during an eye examination by an ophthalmologist or optometrist. The lesions consist of central, fine, whitish granular lesions in