Packed red blood cells do not have an antibody, since the greatest risk of Rh incompatible blood is to current or future pregnancies. For RBCs, type O negative blood is considered a "universal donor" as recipients with types A, B, or AB can almost always receive O negative blood safely. Type AB positive is considered a "universal recipient" because they can receive the other ABO/Rh types safely. These are not truly universal, as other red cell antigens can further complicate transfusions. There are many other human blood group systems and most of them are only rarely associated with transfusion problems. A screening test is
Under a Blood Red Sky Under a Blood Red Sky Under a Blood Red Sky is a live album by Irish rock band U2, produced by Jimmy Iovine and released on 21 November 1983. Along with its companion concert film, "", the release helped establish U2's reputation globally as a live act. The album consists of live recordings from three shows on the band's War Tour, from Colorado and Boston in the US and from Germany. An accompanying concert video entitled "U2 Live at Red Rocks: Under a Blood Red Sky" was released the following year. The film was recorded entirely at the outdoor Red