Brain IA and cardiac Ito currents arise from complexes containing Kv4 voltage-gated potassium channels and cytoplasmic calciumsensor proteins (KChIPs). Here, we present X-ray crystallographic and small-angle X-ray scattering data that show that the KChIP1–Kv4.3 N-terminal cytoplasmic domain complex is a cross-shaped octamer bearing two principal interaction sites. Site 1 comprises interactions ...

Transport of point-size Brownian particles under the influence of a constant and uniform force field through a planar three-dimensional channel with smoothly varying, axis-symmetric periodic side walls is investigated. Here we employ an asymptotic analysis in the ratio between the difference of the widest and the most narrow constriction divided through the period length of the channel geometry...

Electric forces play a key role in the conductance of ions in biological channels. Therefore, their correct treatment is very important in making physical models of ion channels. Here, we present FORTRAN 90 codes for solution of Poisson’s equation satisfying the Dirichlet boundary conditions in realistic channel geometries that can be used in studies of ion channels. For a general channel shape...

We investigated the concentration- and Ca(2+)-dependent effects of CaM mutants, CaM(12) and CaM(34), in which Ca(2+)-binding to its N- and C-lobes was eliminated, respectively, on the Ca(V)1.2 Ca(2+) channel by inside-out patch clamp in guinea-pig cardiomyocytes. Both CaM(12) and CaM(34) (0.7-10muM) applied with 3mM ATP produced channel activity after "rundown". Concentration-response curves we...

We used continuous flow micro-devices as bioreactors for the production of a glycosylated pharmaceutical product (a monoclonal antibody). We cultured CHO cells on the surface of PMMA/PDMS micro-channels that had been textured by micromachining and coated with fibronectin. Three different micro-channel geometries (a wavy channel, a zigzag channel, and a series of donut-shape reservoirs) were tes...

A T-shaped micromixer featuring electroosmotic flow with heterogeneous charged surface patches on the channel walls was analyzed, and an improved design was proposed to enhance mixing performance. Numerical analysis was performed using steady Navier-Stokes equations with an additional electrokinetic body force. The numerical results for species concentration were validated with available experi...

The central device of this thesis is the transistor. It acts like a faucet, but then for electric charge. There is a connection that is called the source, just like the water company. And the charge flows into the drain. Finally there is a handle, here called the gate, to control the flow of charge. The transistor is not an ideal faucet for electrons. For example, even when the gate is closed a...