Takuzo Aida

Image analysis of α/β-tubulin rings in two-dimensional crystalline arrays of periodic mesoporous nanostructures

Two-dimensional crystalline arrays of periodic mesoporous nanostructures, consisting of alpha/beta-tubulin ring-shaped oligomers in the double-layered architecture in an apolar arrangement are successfully prepared with PEM-G buffer containing Arginine nonamers and observed by electron microscopy. The ring-shaped alpha/beta-tubulin assemblies are conformations related to a protofilament, although protofilaments are usually highly constrained in a straight conformation in microtubules. The two-dimensional crystalline arrays appear to have the structure of a square lattice with the layer group P4, the unit cell dimensions of a = b = 36.9 nm and gamma = 90 degrees . The isolated torus-like shaped projections of a pseudo-repeat structural unit are analysed with the method for single particle reconstruction. The average values of outer- and inner-diameters for the torus-like shapes are 49.0 +/- 1.0, and 25.4 +/- 1.1 nm, respectively. The thickness of the peripheral masses consisting of two concentric sub-rings is 11.8 +/- 1.0 nm, where alpha/beta-tubulin heterodimers appear to reside alternately. Taking the average sizes of the rings and the crystallographic unit cell dimensions into consideration, the discussion is focused on the most probable arrangement of the alpha/beta-tubulin rings in the two-dimensional crystalline arrays.

Fast fully plastic actuator based on ionic-liquid-based bucky gel

In previous papers, we reported the first dry actuator that can be fabricated simply by layer-by-layer casting, using bucky gel, a gelatinous room-temperature ionic liquid containing single-walled carbon nanotubes (SWNTs). The actuator has a bimorph configuration with a polymer-supported internal ionic liquid electrolyte layer sandwiched by polymer-supported bucky-gel electrode layers, which allow quick and long-lived operation in air at low applied voltages. In this paper, some of the recent developments of the actuator performance are reported.