Georgia Institute of Technology College of Sciences

The viruses that infect bacteria have a hallowed position in the development of modern biology, and once inspired Max Delbruck refer to them as "the atom of biology". Recently, these viruses have become the subject of intensive physical investigation. Using single-molecule techniques, it is actually possible to watch these viruses in the act of packing and ejecting their DNA. This talk will begin with a general introduction to viruses and their life cycles and will then focus on simple physical arguments about the forces that attend viral DNA packaging and ejection, predictions about the ejection process and single-molecule measurements of ejection itself.

The paper "Complete probabilistic analysis of RNA shapes" (2006) by Voss, Giegerich, and Rehmsmeier will be discussed.

The 5th in a series of 9 mini-conferences features Jacob Fox as the prominent researcher who will give 2 fifty-minute lectures and 4 other outstanding researchers each giving one fifty-minute lecture. There will also be several 25-minute lectures by young researchers and graduate students. The lectures will begin at 1 PM on Saturday, February 25 and conclude at at noon on Sunday, February 26.To register, please send an email to rg@mathcs.emory.edu and for complete details, see the website. Registration is free.

There are over 28,000 species of fishes, and a key feature of this remarkable evolutionary diversity is a great variety of propulsive systems used by fishes for maneuvering in the aquatic environment. Fishes have numerous control surfaces (fins) which act to transfer momentum to the surrounding fluid. In this presentation I will discuss the results of recent experimental kinematic and hydrodynamic studies of fish fin function, and their implications for the construction of robotic models of fishes. Recent high-resolution video analyses of fish fin movements during locomotion show that fins undergo much greater deformations than previously suspected and fish fins possess an clever active surface control mechanism. Fish fin motion results in the formation of vortex rings of various conformations, and quantification of vortex rings shed into the wake by freely-swimming fishes has proven to be useful for understanding the mechanisms of propulsion. Experimental analyses of propulsion in freely-swimming fishes have led to the development of a variety of self-propelling robotic models: pectoral fin and caudal fin (tail) robotic devices, and a flapping foil model fish of locomotion. Data from these devices will be presented and discussed in terms of the utility of using robotic models for understanding fish locomotor dynamics.