Lichen sclerosus and lichen planus are fairly common, non cancerous skin conditions. They can affect different parts of the body, but commonly affect the vulva. When they affect the skin of the vulva, theyâre known as vulval LS or LP.
A gap-graded soil is a soil that has an excess or deficiency of certain particle sizes or a soil that has at least one particle size missing. An example of a gap-graded soil is one in which sand of the No. 10 and No. 40 sizes are missing, and all the other sizes are present.
Quicksand is a mixture of sand and water, or sand and air, that looks solid, but becomes unstable when disturbed by any additional stress. In normal sand, grains are packed tightly together to form a rigid mass, with about 25 to 30 percent of the space (voids) between the grains filled with air or water.