The purpose of this study is to determine the life span and functional characteristics of platelets derived from whole blood that has been stored in a refrigerator for up to 21 days. Currently, platelets are separated from red cells shortly after donation and stored at room temperature for no longer than 5 days. This study is considered experimental because; 1) we will be keeping platelets in the original whole blood donor unit in the refrigerator, and 2) we will be reinfusing a small portion of that donation back into the study-subject-donor and tracking how many of the transfused platelets from that unit circulate in the study-subject-donor in the hours and days after transfusion.