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.
Molded cleats and interchangeable cleats are best for natural grass surfaces where you need shoes to bite into the ground for traction. Indoor shoes are best for gym floors, sport courts, asphalt and concrete. This leaves turf shoes, which are designed specifically for turf-covered fields.