There's only a set 25% xp boost no matter how many transmissions you have. Tested it on a character with just one and another with all five. These transmissions also seem to be some sort of super soldier type serum. Patients injected with it were showing increased cognitive and physical capabilities when Clovis Bray was testing it. It's unlikely these transmissions are part of SIVA as they are two very different nanotechnologies.