Stochasticity in Circadian Clocks

Start: 11/09/2011 - 4:15pm
End  : 11/09/2011 - 5:15pm


Linda Petzold (University of California at Santa Barbara)


In mammals, the suprachiasmatic nucleus (SCN), a brain region of about 20,000 neurons, serves as the master circadian clock, coordinating timing throughout the body and entraining the body to daily light cycles. Experiments in which cell-to-cell signaling between SCN neurons is disrupted by physical separation of the cells, or by blocking vasoactive intestinal polypeptide (VIP) mediated signaling, show that the remarkable precision of the circadian clock at the level of the organism relies on this intercellular signaling. In the absence of cell-to-cell signaling, each SCN neuron and the SCN as a whole exhibits a high degree of stochasticity, with significantly less stable oscillations. We describe several novel findings that were obtained via a combination of experiment and discrete stochastic models, explored through wavelet analysis.

About the speaker

Dr. Linda Petzold is currently Professor in the Department of Computer Science (Chair 2003-2007) and the Department of Mechanical Engineering, and Director of the Computational Science and Engineering Program at the University of California Santa Barbara. She received her Ph.D. in Computer Science in 1978 from the University of Illinois. From 1978-1985 she was a member of the Applied Mathematics Group at Sandia National Laboratories in Livermore, California, from 1985-1991 she was Group Leader of the Numerical Mathematics Group at Lawrence Livermore National Laboratory, and from 1991-1997 she was Professor in the Department of Computer Science at the University of Minnesota. Dr. Petzold is a member of the US National Academy of Engineering. She was recently named the Faculty Research Lecturer for 2011, the highest honor that UCSB bestows to its faculty. She is a Fellow of the ASME, SIAM and AAAS. She was awarded the Wilkinson Prize for Numerical Software in 1991, the Dahlquist Prize in 1999, and the AWM/SIAM Sonia Kovalevski Prize in 2003. She served as SIAM (Society for Industrial and Applied Mathematics) Vice President at Large from 2000-2001, as SIAM Vice President for Publications from 1993-1998, and as Editor in Chief of the SIAM Journal on Scientific Computing from 1989-1993.

Millikan Auditorium, Pomona College: entrance is on the north side of the Millikan patio (6th St. and College St.)

Misc. Information

Here is the PDF flyer for this talk. The dinner will be hosted by Ami Radunskaya.

Abstract and info110.88 KB