Nematodes, microscopic worms, are making engineers look twice at their ability to exhibit the "Cheerios effect" when they move in a collective motion.
These parasites will actually stick together like Cheerios swimming in milk in a cereal bowl after a chance encounter "due to capillary force." This observation has made Virginia Tech engineers speculate about the possible impacts on the study of biolocomotion.
Their work appears in the journal, Soft Matter, a publication of the Royal Society of Chemistry, the week of Feb. 7. Soft Matter is the premier journal in the ongoing multidisciplinary work between physics, material science, and biology. http://www.rsc.org/Publishing/Journals/sm/News/impactfactor_2009.asp
Two Harvard physicists first defined the Cheerios effect. In 2005, Dominic Vella and Lakshminarayanan Mahadevan wrote an article on this activity, defined by scientists as relating to fluid mechanics, in the Journal of Physics. They cited its usefulness in the study of self-assembly of small structures. Self-assembly is used in the science of nanotechnology.
Dominic Vella who now teaches at the University of Oxford, United Kingdom, collaborated with Sunghwan "Sunny" Jung, an assistant professor of engineering science and mechanics at Virginia Tech, and his student, Sean Gart, of Salem, Va., a senior in engineering science and mechanics, and authored the new paper, "The collective motion of nematodes in a thin liquid layer."
Their work highlights the behaviors of the nematode Panagrellus redivivus, a creature that feeds on bacteria, in a watery liquid layer that is thinner than a human hair. In this environment the nematodes crawl by creating waves that travel backwards down their body, and the force pushes them forward.
"The inspiration for the project came when we observed the nematodes crawling up
|Contact: Lynn Nystrom|