The authors report on measurements of the phase coherence time, tau phi , as determined from the measurement of weak negative magnetoresistance in narrow pinched Si accumulation layers. Under favourable bias conditions, one-dimensional quantum interference and electron interaction corrections to the conductivity are found. The phase coherence length is then best described in terms of the 1D Nyquist phase-breaking mechanism, with a Landau-Baber (pure metal limit) component which retains its 2D form.

The development of an implantable system designed to deliver drug doses in a controlled manner over an extended time period is reported. Key performance parameters are the physical size, the power consumption and also the ability to perform wireless communications to enable the system to be externally controlled and interrogated. The system has been designed to facilitate wireless power transfer, which is very important for miniaturisation as it removes the need for a battery.

No abstract

A wireless power transfer and communication system based on near-field inductive coupling has been designed and implemented. The feasibility of using such a system to remotely control drug release from an implantable drug delivery system is addressed. The architecture of the wireless system is described and the signal attenuation over distance in both water and phosphate buffered saline is studied. Additionally, the health risk due to exposure to radio frequency (RF) radiation is examined using a biological model. The experimental results demonstrate that the system can trigger the release of drug within 5 s, and that such short exposure to RF radiation does not produce any significant (