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A remarkably simple device is helping scientists find out why mosquitoes
attack some people and ignore others. Ulrich Bernier at the US Department of
Agriculture in Gainesville, Florida, and his colleagues simply asked volunteers
to roll small glass beads between their hands. They then analysed the volatile
chemicals that rubbed off on the glass. Because water from sweat doesn鈥檛 stick
to the beads, this gave the researchers an easy-to-analyse sample of the 350 or
so chemicals that skin secretes (Analytical Chemistry, vol 71, p 1).
鈥淲e鈥檙e trying to develop an attractant that鈥檚 comparable to or better than very
attractive humans and use that in traps,鈥� Bernier says.