Abstract:
An H-bridge switching topology for bi-directional field excitation to null the effects of a rotor's permanent magnets uses both a low-side and a high-side field excitation driver to control the rotor's average field current. A standard proportional control signal for generators using uni-directional field excitation is used to control an H-bridge for bi-directional field excitation. The H-bridge consists of two pair of power switches. In a preferred embodiment, the switches are n-channel MOSFETs. A drive circuit interfaces a logic block with the H-bridge in order to properly bias the power switches.
Abstract:
A biopsy forceps device is provided for obtaining tissue samples at a site within the body, while maintaining access to the site through an access lumen of the biopsy forceps. The device includes an elongate tubular body for introduction into the body and navigation to an area of interest. An inner tubular member having a lumen, or a plurality of lumens, extends through or adjacent the outer tubular member, from the proximal end to the distal end, where cutting jaws are provided. The cutting jaws are rotatably mounted at the distal end of the device and are controlled by movement of the inner tubular member. The inner tubular member is coupled with a handle portion allowing control of the cutting jaws at the proximal end. Access to the lumen of the inner tubular member is gained at the proximal end, where a luer fitting is provided. The lumen of the inner tubular member has a removable optical fiber disposed therethrough and allows for a variety of medical instruments to be inserted so that the instruments can be used coaxially in the same location as where the biopsy sample is taken.
Abstract:
The disclosure relates to maskless deposition and etching and more particularly to maskless deposition and etching of the surface of objects using single and multiple ion sources.
Abstract:
An apparatus and corresponding method for providing convection enhanced delivery of bioactive agent to a tissue site. The apparatus involves the use of semipermeable membranes, typically in the form of one or more hollow fibers, together with a source and conduit of solution containing the bioactive agent to be delivered. The use of hollow fiber technology provides an optimal combination of features, including delivery kinetics and distribution, as compared to conventional (e.g., standard needle) type delivery devices.
Abstract:
An optical scatterometer system enables illumination of a sample material at various angles of incidence without rotating or otherwise moving the sample material.
Abstract:
The disclosure relates to a method and apparatus using ion etching and ion assisted deposition to reform a surface of an object, such as a large lens, from its existing topography to a predetermined topography. The method comprises comparing the existing topography of the surface of the object to the predetermined topography. In one embodiment, the comparison can be used to distinguish objects having surfaces which are readily or economically reformable to the predetermined topography from those which are not suitable for such reforming. The method novelly utilizes an algorithm comprising image restoration. The ion etching structure of the apparatus comprises an ion source grid which can be used to provide an ion beam of a preselected spatial distribution. The grid is constructed of a nonconducting, vacuum compatible material, such as a ceramic sheet coated with a conductive layer on each side. Apertures are drilled through the grid in a selected pattern. The ion beam produced from a plasma source when a suitable voltage is applied across the coatings has a spatial distribution in accordance with the aperture pattern. In one embodiment the coatings comprise discrete corresponding areas on each surface and different voltages are appliable to each area to further control beam spatial distribution. Ion assisted deposition may be simultaneously performed under the algorithm to add material to the surface in accordance with the desired predetermined topography.
Abstract:
A system for use in treating a tissue site, e.g., a site exhibiting or at risk for developing compartment syndrome, the system including a monitor for use in controlling the function and operation of one or more apparatuses providing insertable catheters. The system includes at least one apparatus having a catheter portion that includes both a suitably protected, functional device tip, adapted to be positioned and used within the tissue site, and one or more hollow fiber membranes, e.g., an array of such membranes, adapted to be positioned within the tissue site in order to simultaneously collect fluid therefrom. The catheter portion is adapted to be safely inserted and positioned within the tissue site, in a manner that permits it to function there while substantially minimizing direct impingement of the non-fluid tissue on the functional device tip surface.
Abstract:
A connector having a cylindrical hollow body having a first, closed end and a second, open end. A first external thread extends from the first end toward the second end and a second external thread extends from the second end toward the first end. Additionally, a contact element extends concentrically from the closed first end of the hollow body.
Abstract:
A biopsy forceps device is provided for obtaining tissue samples, or removing tissue for therapeutic reasons, at a site within a body, while maintaining access to the site through an access lumen of the biopsy forceps. The device includes an elongate tubular body for introduction into the body and navigation to an area of interest. An inner tubular member having a lumen, or a plurality of lumens, extends through or adjacent the outer tubular member, from the proximal end to the distal end, where cutting jaws are provided. The cutting jaws are rotatably mounted at the distal end of the device and are controlled by movement of the inner tubular member. The inner tubular member is coupled with a handle portion allowing control of the cutting jaws at the proximal end. Access to the lumen of the inner tubular member is gained at the proximal end, where a luer fitting is provided. The lumen of the inner tubular member has a removable optical fiber disposed therethrough or allows for a variety of medical instruments to be inserted so that the instruments can be used coaxially in the same location as where the biopsy sample is taken.
Abstract:
An optical scatterometer system includes a screen positioned to receive and display a pattern representative of light specularly reflected and scattered from an illuminated sample material and a camera positioned to record the pattern displayed on the screen. The screen may present a curved surface to increase its light gathering capabilities and may be constructed of an electron trapping material, a photochromic material or a pyrochromic material. The screen may contain one or more apertures for passing one or more incident light beams generated by a light source and/or light specularly reflected and scattered from the sample material. The screen may be positioned between the sample material and the light source, or the sample material may be positioned between the screen and the light source.