9401015 Hsia This grant supports the research of Professors J. Hsia to work on problems in number theory. Professor Hsia will continue to work on the arithmetic of integral and hermitian quadratic forms. Inparticular he will work on strong approximation for definite spaces and effectiveness results. He also intends to continue his study of spinor genera. This is research in the field of number theory. Number theory starts with the whole numbers and questions such as the divisibility of one whole number by another. It is among the oldest fields of mathematics and it was originally pursued for purely aesthetic reasons. However, within the last half century, it has become an essential tool in developing new algorithms for computer science and new error correcting codes for electronics.