Abstract: A neurostimulation device is provided. The device has first and second physical electrode elements that cooperate to provide a plurality of virtual electrode pairs. The spacing between the physical elements, as well as the relative surface areas between the respective portions comprising the virtual pairs, is controlled to provide self-selecting and/or self-directing treatment capabilities.

Abstract: A neurostimulation device is provided. The device has first and second physical electrode elements that cooperate to provide a plurality of virtual electrode pairs. The spacing between the physical elements, as well as the relative surface areas between the respective portions comprising the virtual pairs, is controlled to provide self-selecting and/or self-directing treatment capabilities.

Abstract: A system for reliably indexing and separating sidewall core samples obtained with a sidewall coring tool comprises markers made of a magnetic material and a mechanism body made of a combination of magnetic and non-magnetic materials to reliably insert and position markers in between successive core samples. The sidewall core is not altered in any way by the marking process. Further, a flexible rubber boot apparatus is disclosed to ensure the complete transfer of retrieved samples in cases where the sample is broken, shattered or segmented and to ensure that broken, shattered or segmented cores will be retrieved in cases where the borehole is horizontal and the tool must operate in a horizontal position or in any other rotational orientation.