Radial Splitting Research Articles

Histological Development of the Green Bean Pod as Related to Culinary Texture.

SUMMARY— The different tissues of the green pod exhibit a wide range in cellular structure and composition at edible maturities. Large substomatal spaces and intercellular spaces in outer parenchyma and thick‐walled hypodermis contribute to cell separation or sloughing when the beans are cooked. Cells of the outer parenchyma contain numerous starch granules, are thicker walled than the inner parenchyma cells, and usually are not torn as a result of freezing. Cells of the inner parenchyma are thin‐walled and form a compact, succulent tissue with only minute intercellular spaces. Slow rates of freezing result in radial cracks often extending into the young fiber sheath lying between the inner and outer parenchyma zones. With more rapid freezing small cracks sometimes appear only in close association with the immature fiber sheath cells.Prolonged immersion freezing usually results in radial splitting throughout all tissues without respect to differences in structure and composition. In pods overly mature for culinary use wall thickening and lignification of sheath sheath and sclereid caps contribute to toughness and stringiness. Other histological aspects of texture qualities involve growth environment and postharvest conditions.

Fagot lasers

Fagot lasers have been constructed by holding a nnmher of identical laser rods in cages consisting of blllkheads held together by tie rods. The bulkheads separate the rods to allow water flow between them and prevent them from saging or moving in translation or rotation. The fagot laser is then held in the usual laser cavity hardware in a similar manner to a solid cylindrical laser rod. The fagot configuration is motivated by the desire to operate glass laser systems at high average input power which can produce radial splitting of the rod due to the tangential stress caused by the cooling gradient from center to edge. Analysis shows that the fagot, laser can have substantially greater power handling capability than a solid rod of the same volume and length.

Ultrastructure of hemocyanin components from the gastropod Buccinum undatum

The molecular components of Buccinum undatum hemocyanin and their mode of dissociation and aggregation have been studied with the electron microscope. Shadow casting and positive and negative staining techniques have been used. The prevailing molecule in native hemocyanin material, the B-component molecule of earlier ultracentrifuge studies, probably consists of a tube containing inside at each end a shorter tube, with the same axial orientation. Each of the inner tubes is connected to the outer tube by twenty bridges. Centrally in the molecule where no tube is found, a small body is situated. When the pH in a solution of native hemocyanin is lowered to near the isoelectric point, two kinds of linear aggregate of B-component molecules are found. When pH is raised, some of the B-component molecules dissociate into two parts through a plane perpendicular to the long axis of the tube. These parts represent the C-component. Complexes of one B- and one C-component molecule are often observed in these solutions. These complexes have been correlated with the A-component. B- and C-component molecules may show a radial splitting of the inner tubes into five parts. It is proposed that this is the initial process in the formation of H-component molecules. H-component molecules are therefore considered to be a tenth of B-component molecules, not an eighth part, as indicated by previous molecular weight determinations of B- and C-component molecules.

Disc Protrusion in the Cat: Ventral Protrusions and Radial Splits

SUMMARY Ventral protrusions and radial splits of the intervertebral discs have been investigated in 100 adult cats, 50 being of known age. Forty-eight of the latter were also examined for osteophytes. The ventral protrusions were either diffuse mounds or discrete knobs; clear splits of the annulus usually led towards the protrusion, but the annulus was seldom completely perforated. They were found in 23 cats. Forty-nine discs were affected, most of them (69 per cent) being between T10 and S1. There were no true lateral protrusions. In 15 cats with ventral protrusions there were 189 discs with osteophytes, and 21 of these had a ventral protrusion as well: 12 other discs had ventral protrusions, but no osteophytes. It cannot be said that osteophytes cause ventral protrusions, nor vice versa, but there was some statistical evidence that they may share causal factors in the cervical and lumbar regions. Radial splits consisted of outward distortion or radial rupture of lamellae unaccompanied by protrusion. These were found in 27 cats, affecting 43 discs, most of which (58 per cent) lay between T10 and S1, Ventral splits accounted for 60 per cent, and these occurred mostly between T10 and S1. Dorsal splits (19 per cent) were mainly cervical. Lateral splits (21 per cent) were irregularly scattered. Radial splits may be precursors of protrusions. Radial splits first occurred at 6 years old, ventral protrusions at 10. Over 80 per cent of both were found in cats 14 years old or more; therefore, both are essentially phenomena of senility. The nucleus pulposus was still gelatinous in 20 per cent of discs with ventral protrusions and 9 per cent with radial splits. This casts doubt on the orthodox concept that protrusions originate from degeneration of the nucleus pulposus. The findings suggest that one set of anatomical or biomechanical factors is needed to explain the distribution of dorsal protrusions and another for ventral protrusions. The low incidence of radial splits and ventral protrusions in the first 9 thoracic discs indicates that the conjugal ligament is not the only factor restricting dorsal protrusion in this region.