Here's what I found a while back when seeking info about tumor necrosis. 1) Necrosis in the tumor means that the cancer cells in that area are dead. The pathologic finding of necrosis suggests a fast-growing cancer. This often happens because the tumor runs out of blood supply in the central portion. Without a blood supply, the tumor cells cannot live.
In association football, where the shoes themselves are known as football boots, there are three different cleat types. There are soft ground cleats which are made for wet weather. The soft ground cleats are always replaceable, and are almost always metal, so when they wear down they are easy to replace.
Common modern formations. The following formations are used in modern football. The formations are flexible allowing tailoring to the needs of a team, as well as to the players available. Variations of any given formation include changes in positioning of players, as well as replacement of a traditional defender by a sweeper.