Abstract: The present invention encompasses tools and a tool-holding retractor assembly. The retractor assembly spreads an incision and holds the incision open. At least one extension device, having a tool holder on one end, attaches to the assembly. The holder includes a selectively locking multi-axis adjustable mounting element adapted to grip a tool shaft. The mounting element acts as a universal mounting providing rotational and sliding movement of the tool shaft. The extension device adjusts to position the tool holder peripherally of the surgical field. Once the retractor is placed, the extension device provides full access to regions below the incision. The extension device allows the surgeon to chose the insertion point and insertion angle of the tool shaft.

Abstract: Apparatus for determining the location of a signal-generating source (e.g., a conferee in a telephone conference) includes at least three sensors (e.g., microphones) arranged in a plurality of sets, each having two or more sensors. A surface-finding element responds to receipt at each sensor set of signals (e.g., speech) from the source for identifying a geometric surface (e.g., the surface of a hyperboloid or cone) representing potential locations of the source as a function of sensor locations and time difference of arrival of the signals. A location-approximating element coupled to two or more of the sets identifies a line that further defines potential source locations at the intersection of the surfaces. A location signal representing those potential locations is generated in accord with parameters of that line. Further functionality generates generating the location signal as a function of closest intersections the plural ones of the aforementioned lines.