Nematode worms do not usually react to ultrasound, but Chalasani found that they did when they were surrounded by a fluid containing microscopic bubbles.
Sukkulamadot eivät normaalisti reagoi ultraääneen. Chalasani huomasi, että madot kuitenkin alkavat reagoida, kun ne asetetaan nesteeseen, jossa on mikroskooppisen pieniä kuplia.