Transfer properties in radical theory

A functor is said to reflect radical classes if under this functor the inverse image of a radical class is always a radical class.Prototypical examples of such functors include polynomial and matrix functors and various forgetful functors.This paper is for the most part a survey of known results concerning radical reflections,but there are a few new results,including a generalization to right alternative rings of a well known result of Andrunakievici on upper radicals of simple associative rings.