Researchers, Developers and Staffs
Hidetaka  YAMAOKA Hidetaka YAMAOKA

Research Themes

Continuum modeling of actin cytoskeleton
Study on geometric structures of microcontinuum

Research Subjects and Results

In this program, we have studied microcontinuum theory based on the viewpoint of differential geometry, because mechanical behaviors of higher order structures of actin filaments intertwining factors at various temporal and spatial scales should be modeled together with behaviors at smaller scales. The microcontinuum theory is described as a dynamics on the tangent bundle over a vector bundle and equations of motion for an elastic body with microstructures are derived. As a result, macro-micro coupled behaviors can be investigated straightforwardly. Moreover, we considered applications of the formulation of the microcontinuum to continuum models of the actin cytoskeletons. In particular, investigation of the actin filament describing by this model suggests that ensile-torsional coupling behavior is caused by geometric asymmetry of filament. In addition, the filamentous model can be extended to detailed model considering subdomain structure of actin monomers as the microstructure.

Future Target

The actin cytoskeletons can be considered as a microcontinuum, in various temporal and spatial scales, that is, the cytoskeleton in cellular scale, the filaments constructing the cytoskeleton, and monomers (or subdomain structures) forming the filament are regarded as the microstructure. Remainder works are that the higher order structures are concretely modeled and that their behaviors are investigated. These modeling and analysis are possible to find a macroscopic properties caused by deformations of the microstructures. In addition, if macroscopic biochemical phenomena are explained by microscopic mechanical behaviors, our techniques will be an interesting new method for biomechanical research.

Selected Publications

Hidetaka Yamaoka, Shinji Matsushita, Yoshitaka Shimada, Taiji Adachi
Multiscale modeling and mechanics of filamentous actin cytoskeleton
Journal of Biomechanics and Modeling in Mechanobiology (submitted)

Hidetaka Yamaoka, Taiji Adachi
Continuum dynamics on a vector bundle for a directed medium
Journal of Physics A: Mathematical and Theoretical, Volume 43, Number 32, 325209 (15pp) (2010)

Journal of Physics A: Mathematical and Theoretical, Volume 43, Number 32, 325209 (15pp) (2010)
Coupling between axial stretch and bending/twisting deformation of actin filament caused by a mismatched centroid from the center axis
International Journal of Mechanical Sciences, Volume 52, Issue 2, pp.329-333 (2010)

Hidetaka Yamaoka, Taiji Adachi
Geometrical settings of directed medium by vector bundle description and its application to biomechanics
SES 2010: the 47th Anuual Technical Meeting of Society of Engineering Science, Ames, USA, October (2010)

Hidetaka Yamaoka, Taiji Adachi
Cosserat theoretical modeling of single actin filament as a twisted elastic filament
ICTAM 2008: the 22nd International Congress of Theoretical and Applied Mechanics, Adelaide, Australia, August (2008)

Hidetaka Yamaoka, Taiji Adachi
A study on mechanical behavior of single actin filament through continuum modeling
AP Biomech 2007: the 3rd Asian Pacific Conference on Biomechanics, Tokyo, Japan, Novenber (2007)

Selected Publications Page