one of a group of cells that develop in the walls of the seminiferous tubules. Spermatogenic cells include spermatogonia, spermatocytes, and spermatidsâall of which are transitional forms between primary sexual cells and spermatozoa.
long-haul optics. Long-haul optics refers to the transmission of visible light signals over optical fiber cable for great distances, especially without or with minimal use of repeaters. Normally, repeaters are necessary at intervals in a length of fiber optic cable to keep the signal quality from deteriorating to the point of non-usability. In long-haul optical systems, the goal is to minimize the number of repeaters per unit distance, and ideally, to render repeaters unnecessary.
Ramie fiber. Ramie fiber is one of the premium vegetable fibers. The ultimate fibers are exceptionally long and are claimed to be the longest of vegetable origin, with one report claiming the fibers range up to 580 mm, averaging about 125 mm. Ramie fiber is very durable, is pure white in colour and has a silky luster.It is reported to have a tensile strength eight times that of cotton and seven times greater than silk. However, other reports claim that the tensile strengths of cotton, flax, hemp and ramie are similar.amie (Boehmeria nivea. The true ramie or China Grass' is also known as white ramie' and is the Chinese cultivated plant. It has large heart shaped, crenate leaves covered on the underside with white hairs that give it a silvery appearance. Boehmeria nivea var. tenacissima, is known as green ramie' or rhea'.