What are we doing here? Maybe a scientific experiment?

"What are we doing here? Maybe a scientific experiment?"

ESA's Italian astronaut Paolo Nespoli and NASA astronaut Cady Coleman are doing something in this picture...but what?

Paolo and Cady are serving at the International Space Station as a flight engineers with Dmitri Kondratyev, Oleg Skripochka, Alexander Kaleri and commander Scatt Kelly as members of Expedition 26.

Paolo’s MagISStra mission is Europe’s third long-duration mission on the ISS.