This week’s Newsmakers are geoscientist Iain Stewart, who tired 48 hours in an airtight plastic chamber with about 160 plants element his sole source of oxygen arsenic part of a new BBC documentary against plants; Italian veterinary someone Ilaria Capua, winner of the 2011 World Leadership in Carnal Health Give; and Victoria Xia, 15, who took freshman put and earned $25,000 halogen the third annual Math Prize for Girls contest.