DEFENDING THE EARTH FROM LONG-PERIOD COMETS AND SNEAKY ASTEROIDS: SHORT TERM THREAT RESPONSE REQUIRES LONG TERM PREPARATION.

Comets, such as the recent Comet C/2013 A1 (Siding Spring) can impact terrestrial planets with very short warning times: for Siding Spring the time from discovery to closest approach to Mars (135,000 km) was less than 22 months. Short warning times are also possible for certain asteroids approaching on unfavorable orbits from the direction of the Sun. The time required to design, build, test and launch a high-reliability Interceptor spacecraft is on the order of 5 years, a timescale incompatible with threat mitigation for such short warning times.

In vivo and in vitro comparison of the charge injection capacity of platinum macroelectrodes.

Platinum (Pt) is the most commonly used metal for stimulating electrodes. This study aims to determine the amount of charge that can be delivered without causing irreversible electrochemical reactions (charge injection capacity, Q inj) of Pt macroelectrodes (geometric surface area >0.001 cm(2)) in vitro and in vivo using voltage transient measurements.

Safety and efficacy of explanting or replacing suprachoroidal electrode arrays in a feline model.

Background: A key requirement for retinal prostheses is the ability for safe removal or replacement. We examined whether suprachoroidal electrode arrays can be removed or replaced after implantation.

Methods: Suprachoroidal electrode arrays were unilaterally implanted into 13 adult felines.

Electrical stimulation of retinal ganglion cells with diamond and the development of an all diamond retinal prosthesis.

Electronic retinal implants for the blind are already a market reality. A world wide effort is underway to find the technology that offers the best combination of performance and safety for potential patients. Our approach is to construct an epi-retinally targeted device entirely encapsulated in diamond to maximise longevity and biocompatibility.

Biocompatibility of immobilized aligned carbon nanotubes.

In vivo host responses to an electrode-like array of aligned carbon nanotubes (ACNTs) embedded within a biopolymer sheet are reported. This biocompatibility study assesses the suitability of immobilized carbon nanotubes for bionic devices. Inflammatory responses and foreign-body histiocytic reactions are not substantially elevated when compared to negative controls following 12 weeks implantation.