Silicon micromachining and thin-film technology have been employed to fabricate iridium stimulating arrays which can be used to excite discrete volumes of the central nervous system. Silicon multichannel probes with thicknesses ranging from 1 to 40 microns and arbitrary two-dimensional shapes can be fabricated using a high-yield, circuit-compatible process. Iridium stimulating sites are shown to have similar characteristics to iridium wire electrodes. Accelerated pulse testing with over 8 million 100 microA biphasic current pulses on 8000 microns 2 sites has demonstrated the long-term stability of iridium and activated iridium sites. In vivo tests have been performed in the central auditory pathways to demonstrate neural activation using the devices. These tests show a selective activation both as a function of site separation and site size.

One hundred and twenty-six blood samples were collected from healthy sheep and goats in Xinjiang, China, during July 2014. Seventy-three samples (57.93%) were bluetongue virus (BTV) serology-positive, and 39 samples (30.95%) were BTV NS1 gene-positive. BTV strain XJ1407 was isolated from the blood of BTV NS1 gene-positive animals and sequenced. Analysis of its genome sequence suggests that XJ1407 is a novel BTV serotype.

A simple, compact, and highly sensitive optical fiber directional bend sensor is presented. This device consists of a lateral-offset splicing joint and an up-taper formed through excessive fusion splicing method. The lateral-offset splicing breaks the cylindrical symmetry of the fiber and defines a pair of directions along which the bending response of the Mach-Zehnder interferometer transmission spectrum is different and thus could be used for bending vector measurement. For a curvature range from -3 to 3 m(-1), the bending sensitivities at 1463.86 nm and 1548.41 nm reach 11.987 nm/m(-1) and 8.697 nm/m(-1), respectively.

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As part of a program to determine the feasibility of a CNS auditory prosthesis, the tissue reaction to electrodes chronically implanted in the cochlear nucleus (CN) of the guinea pig was examined. Varied open operative approaches and microelectrode designs were utilized. Silicon substrate thin film and platinum-iridium wire electrodes, tethered and untethered, were placed successfully in different divisions of the CN. Implantation through a posterior suboccipital approach was most successful. Histologic examinations demonstrated a glial cell proliferation confined to the area of the electrode track that never exceeded 15 microns in width. No neuronal loss or significant effect on cell morphology was seen, and reactive cells were absent. Electrode migration was apparent in a minority of animal preparations. Although potential problems were identified, our findings lend support to the feasibility of implanting a neuroprosthesis in the CN and have helped to establish methods for future studies of chronic intranuclear stimulation.

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