Marsha Lester, Andrea Liu and Amita Sehgal of the University of Pennsylvania have been elected to the National Academy of Sciences, considered one of the highest honors accorded a U.S. scientist or engineer.

Lester is the Edmund J. Kahn Distinguished Professor in the Department of Chemistry and Liu is the Hepburn Professor of Physics in the Department of Physics and Astronomy, both in Penn's School of Arts & Sciences. Sehgal is the John Herr Musser Professor of Neuroscience and director of the Chronobiology Program in Penn’s Perelman School of Medicine.

Selected for "their distinguished and continuing achievements in original research," the three scientists are part of the 2016 Academy class of 84 members and 21 foreign associates from 14 countries.

Lester uses laser spectroscopic techniques to elucidate intermediate steps that direct the outcome of chemical reactions. Her work has focused on oxidation chemistry in atmospheric and combustion environments.

Liu studies theoretical problems in soft and living matter physics, using theoretical and computational approaches.  She is best known for her work on jamming, a new way of thinking about the development of rigidity in solids.

Sehgal studies the molecular and genetic components of sleep and circadian, or 24-hour, rhythms. Using the fruit fly, she and others have characterized a molecular clock present in flies and humans. Sehgal is also a Howard Hughes Medical Institute investigator.

A full list of 2016 Academy Members is here.