A chrysanthemum overlaid with the chemical formula for pyrethrins

What Do Pesticides and Chrysanthemums Have in Common?

They both contain insecticides called pyrethrins, used in ancient Persia. Today we use them in lice-killing shampoos.
US Embassy Havana Cuba

The Science Behind Sonic Incidents

U.S. government employees stationed in Havana, Cuba, and Guangzhou, China, have experienced mysterious symptoms. Could the culprit be a sonic weapon?