ELFT HÍRADÓ

[Károlyi György <karolyi AT tas.me.bme.hu>]

MEGHÍVÓ 

*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  * 

Philip J. Holmes 
Eugene Higgins Professor of Mechanical and Aerospace Engineering 
Professor of Applied Mathematics 
Princeton University 

The neuromechanics of lamprey swimming or, 
An elastic rod with a mind of its own 

2009. október 8. csütörtök, 15.00 óra

*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  * 

Az előadás helye:
MTA Székház, Kisterem

Az előadás tartalma:  
Locomotion provides superb examples of cooperation among
neuromuscular systems, environmental reaction forces, and sensory
feedback. As part of a program to understand the neuromechanics of
locomotion, here we construct a model of anguilliform (eel-like)
swimming in slender fishes. Building on a continuum mechanical
representation of the body as an viscoelastic rod, actuated by a
traveling wave of preferred curvature and subject to simplified
hydrodynamic reaction forces, we incorporate a new version of a
calcium release and muscle force model, fitted to data from the
lamprey Ichthyomyzon unicuspis, that interactively generates the
curvature wave. We use the model to investigate the source of the
difference in speeds observed between electromyographic waves of
muscle activation and mechanical waves of body curvature, concluding
that it is due to a combination of passive viscoelastic and geometric
properties of the body and active muscle properties. Moreover, we
find that nonlinear force dependence on muscle length and shortening
velocity may reduce the work done by the swimming muscles in steady
swimming.

Minden érdeklődőt szívesen látunk.