What Rojan demonstrates is more like transporter technology. It isn't simply desiccating the victim by removing all the water. It is (as Metryq points out) also reducing clothes and boots.
I invoke transporter technology because the reduced objects seem to be data storage units-- but with no mechanism. The "cube" itself is
the data, stored in the pattern of its molecules.
There must be a nearby storage place for the missing mass that makes up each person. That mass is later recalled and reassembled according to the data in the cube.