Direct measurement of osmotic pressure via adaptive confinement of quasi hard disc colloids.

Confining a system in a small volume profoundly alters its behaviour. Hitherto, attention has focused on static confinement where the confining wall is fixed such as in porous media. However, adaptive confinement where the wall responds to the interior has clear relevance in biological systems.

TRIC channels supporting efficient Ca(2+) release from intracellular stores.

Trimeric intracellular cation-selective (TRIC) channel subtypes, namely TRIC-A and TRIC-B, are derived from distinct genes and distributed throughout the sarco/endoplasmic reticulum (SR/ER) and nuclear membranes. TRIC-A is preferentially expressed at high levels in excitable tissues, while TRIC-B is ubiquitously detected at relatively low levels in various tissues. TRIC channels are composed of ~300 amino acid residues and contain three putative membrane-spanning segments to form a bullet-shaped homo-trimeric assembly.

Self-filtering oscillations in carbon nanotube hetero-junctions.

We evaluate the vibrational properties of single-wall carbon nanotube (SWCNT) hetero-junction (HJ) oscillators using a hybrid atomistic-continuum approach validated by molecular mechanics/molecular dynamics simulations. The SWCNT-HJs show a broken symmetry topology of their mode shapes, with striction effects caused on the bending and radial modes by the combined effect of the HJ and the tube with the thinner radius. The single-wall nanotube HJs also show selective mass sensing properties based solely on the geometry and type of the boundary conditions of the specific nanostructure.

Ca²+-dependent phosphorylation of RyR2 can uncouple channel gating from direct cytosolic Ca²+ regulation.

Phosphorylation of the cardiac ryanodine receptor (RyR2) is thought to be important not only for normal cardiac excitation-contraction coupling but also in exacerbating abnormalities in Ca²+ homeostasis in heart failure. Linking phosphorylation to specific changes in the single-channel function of RyR2 has proved very difficult, yielding much controversy within the field. We therefore investigated the mechanistic changes that take place at the single-channel level after phosphorylating RyR2 and, in particular, the idea that PKA-dependent phosphorylation increases RyR2 sensitivity to cytosolic Ca²+.