Patents Represented by Attorney, Agent or Law Firm Hardie R. Barr
  • Patent number: 6135729
    Abstract: An apparatus is are provided for a blood pump bearing system within a pump housing to support long-term high-speed rotation of a rotor with an impeller blade having a plurality of individual magnets disposed thereon to provide a small radial air gap between the magnets and a stator of less than 0.025 inches. The bearing system may be mounted within a flow straightener, diffuser, or other pump element to support the shaft of a pump rotor. The bearing system includes a zirconia shaft having a radiused end. The radiused end has a first radius selected to be about three times greater than the radius of the zirconia shaft. The radiused end of the zirconia shaft engages a flat sapphire endstone. Due to the relative hardness of these materials a flat is quickly produced during break-in on the zirconia radiused end of precisely the size necessary to support thrust loads whereupon wear substantially ceases.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: October 24, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Gregory S. Aber
  • Patent number: 6134476
    Abstract: Method and apparatus are provided for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna (700) is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 Gigahertz and 12 Gigahertz is applied to monopole microwave radiator (600) having a surface wave limiter (606).
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: October 17, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: G. Dickey Arndt, James R. Carl, George W. Raffoul, Vincent G. Karasack, Antonio Pacifico, Carl F. Pieper
  • Patent number: 6132536
    Abstract: An automated propellant blending apparatus and method uses closely metered addition of countersolvent to a binder solution with propellant particles dispersed therein to precisely control binder precipitation and particle aggregation. A profile of binder precipitation versus countersolvent-solvent ratio is established empirically and used in a computer algorithm to establish countersolvent addition parameters near the cloud point for controlling the transition of properties of the binder during agglomeration and finishing of the propellant composition particles. The system is remotely operated by computer for safety, reliability and improved product properties, and also increases product output.
    Type: Grant
    Filed: October 7, 1998
    Date of Patent: October 17, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Carl W. Hohmann, Douglas W. Harrington, Maureen L. Dutton, Billy Charles Tipton, Jr., James W. Bacak, Frank Salazar
  • Patent number: 6110730
    Abstract: An apparatus and method for using the apparatus for staining particular cell markers is disclosed. The apparatus includes a flexible tube that is reversibly pinched into compartments with one or more clamps. Each compartment of the tube contains a separate reagent and is in selective fluid communication with adjoining compartments.
    Type: Grant
    Filed: June 26, 1996
    Date of Patent: August 29, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Clarence F. Sams, Vaughan L. Clift, Kelly E. McDonald
  • Patent number: 6097189
    Abstract: A portable system is provided that is operational for determining, with three dimensional resolution, the position of a buried object or a proximately positioned object that may move in space or air or gas. The system has a plurality of receivers for detecting the signal from a target antenna and measuring the phase thereof with respect to a reference signal. The relative permittivity and conductivity of the medium in which the object is located is used along with the measured phase signal to determine a distance between the object and each of the plurality of receivers. Knowing these distances, an iteration technique is provided for solving equations simultaneously to provide position coordinates. The system may also be used for tracking movement of an object within close range of the system by sampling and recording subsequent positions of the object.
    Type: Grant
    Filed: September 29, 1997
    Date of Patent: August 1, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: G. Dickey Arndt, James R. Carl
  • Patent number: 6077478
    Abstract: A device and method for elimination of contamination during transfer of materials either into or from bioreactors, food containers, or other microbially vulnerable systems. Using microwave power, thermal sterilizations of mating fixtures are achieved simply, reliably, and quickly by the volatilization of small quantities of water to produce superheated steam which contacts all exposed surfaces.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: June 20, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Richard L. Sauer, James E. Atwater, Roger W. Dahl, Frank C. Garmon, Teddie D. Lunsford, William F. Michalek, Richard R. Wheeler, Jr.
  • Patent number: 6074871
    Abstract: A method for making a biocompatible polymer article using a uniform atomic oxygen treatment is disclosed. The substrate may be subsequently optionally grated with a compatibilizing compound. Compatibilizing compounds may include proteins, phosphorylcholine groups, platelet adhesion preventing polymers, albumin adhesion promoters, and the like. The compatibilized substrate may also have a living cell layer adhered thereto. The atomic oxygen is preferably produced by a flowing afterglow microwave discharge, wherein the substrate resides in a sidearm out of the plasma. Also, methods for culturing cells for various purposes using the various membranes are disclosed as well. Also disclosed are porous organic polymers having a distributed pore chemistry (DPC) comprising hydrophilic and hydrophobic regions, and a method for making the DPC by exposing the polymer to atomic oxygen wherein the rate of hydrophilization is greater than the rate of mass loss.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: June 13, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Steven L. Koontz
  • Patent number: 6050987
    Abstract: A system for coupling a vascular overflow graft or cannula to a heart pump. A pump pipe outlet is provided with an external tapered surface which receives the end of a compressible cannula. An annular compression ring with a tapered internal bore surface is arranged about the cannula with the tapered internal surface in a facing relationship to the external tapered surface. The angle of inclination of the tapered surfaces is converging such that the spacing between the tapered surfaces decreases from one end of the external tapered surface to the other end thereby providing a clamping action of the tapered surface on a cannula which increases as a function of the length of cannula segment between the tapered surfaces. The annular compression ring is disposed within a tubular locking nut which threadedly couples to the pump and provides a compression force for urging the annular ring onto the cannula between the tapered surfaces. The nut has a threaded connection to the pump body.
    Type: Grant
    Filed: September 21, 1998
    Date of Patent: April 18, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Bernard J. Rosenbaum
  • Patent number: 6047216
    Abstract: Method and apparatus are provided to treat atherosclerosis wherein the artery is partially closed by dilating the artery while preserving the vital and sensitive endothelial layer thereof Microwave energy having a frequency from 3 GHz to 300 GHz is propagated into the arterial wall to produce a desired temperature profile therein at tissue depths sufficient for thermally necrosing connective tissue and softening fatty and waxy plaque while limiting heating of surrounding tissues including the endothelial laser and/or other healthy tissue, organs, and blood. The heating period for raising the temperature a potentially desired amount, about 20.degree. C., within the atherosclerotic lesion may be less than about one second. In one embodiment of the invention, a radically beveled waveguide antenna is used to deliver microwave energy at frequencies from 25 GHz or 30 GHz to about 300 GHz and is focused towards a particular radial sector of the artery.
    Type: Grant
    Filed: August 5, 1998
    Date of Patent: April 4, 2000
    Assignee: The United States of America represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: James R. Carl, G. Dickey Arndt, Patrick W. Fink, N. Reginald Beer, Phillip D. Henry, Antonio Pacifico, George W. Raffoul
  • Patent number: 6022902
    Abstract: Porous organic articles having no surface functionality may be treated by remote plasma discharge to thereby introduce functionality to the surface of the article. The functionality is introduced throughout the article's surface, including the exterior surface and the surfaces of the pores. Little or no degradation of the porous organic article occurs as a result of the functionalization. Amino, hydroxyl, carbonyl and carboxyl groups may be introduced to the article. In this way, an essentially inert hydrophobic porous article, made from, for example, polyethylene, can have its surface modified so that the surface becomes hydrophilic. The remote plasma discharge process causes essentially no change in the bulk properties of the organic article. The remote plasma discharge process is preferably conducted so that no photons, and particularly no ultraviolet radiation, is transmitted from the plasma glow to the porous article.
    Type: Grant
    Filed: May 14, 1997
    Date of Patent: February 8, 2000
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Steven L. Koontz
  • Patent number: 5957672
    Abstract: Methods and apparatus are provided for a blood pump bearing system within a pump housing to support long-term high-speed rotation of a rotor with an impeller blade having a plurality of individual magnets disposed thereon to provide a small radial air gap between the magnets and a stator of less than 0.025 inches. The bearing system may be mounted within a flow straightener, diffuser, or other pump element to support the shaft of a pump rotor. The bearing system includes a zirconia shaft having a radiused end. The radiused end has a first radius selected to be about three times greater than the radius of the zirconia shaft. The radiused end of the zirconia shaft engages a flat sapphire endstone. Due to the relative hardness of these materials a flat is quickly produced during break-in on the zirconia radiused end of precisely the size necessary to support thrust loads whereupon wear substantially ceases.
    Type: Grant
    Filed: June 17, 1996
    Date of Patent: September 28, 1999
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Gregory S. Aber
  • Patent number: 5939314
    Abstract: A method for making a biocompatible polymer article using a uniform atomic oxygen treatment is disclosed. The substrate may be subsequently optionally grated with a compatibilizing compound. Compatibilizing compounds may include proteins, phosphorylcholine groups, platelet adhesion preventing polymers, albumin adhesion promoters, and the like. The compatibilized substrate may also have a living cell layer adhered thereto. The atomic oxygen is preferably produced by a flowing afterglow microwave discharge, wherein the substrate resides in a sidearm out of the plasma. Also, methods for culturing cells for various purposes using the various membranes are disclosed as well. Also disclosed are porous organic polymers having a distributed pore chemistry (DPC) comprising hydrophilic and hydrophobic regions, and a method for making the DPC by exposing the polymer to atomic oxygen wherein the rate of hydrophilization is greater than the rate of mass loss.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: August 17, 1999
    Assignee: The United States of America as represented the Administrator of the National Aeronautics and Space Administration
    Inventor: Steven L. Koontz
  • Patent number: 5935845
    Abstract: A method for making a biocompatible polymer article using a uniform atomic oxygen treatment is disclosed. The substrate may be subsequently optionally grated with a compatibilizing compound. Compatibilizing compounds may include proteins, phosphorylcholine groups, platelet adhesion preventing polymers, albumin adhesion promoters, and the like. The compatibilized substrate may also have a living cell layer adhered thereto. The atomic oxygen is preferably produced by a flowing afterglow microwave discharge, wherein the substrate resides in a sidearm out of the plasma. Also, methods for culturing cells for various purposes using the various membranes are disclosed as well. Also disclosed are porous organic polymers having a distributed pore chemistry (DPC) comprising hydrophilic and hydrophobic regions, and a method for making the DPC by exposing the polymer to atomic oxygen wherein the rate of hydrophilization is greater than the rate of mass loss.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: August 10, 1999
    Assignee: The United States of America as represented by theAdministrator, National Aeronautics and Space Administration
    Inventor: Steven L. Koontz
  • Patent number: 5904709
    Abstract: Method and apparatus are provided for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna (700) is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 Gigahertz and 12 Gigahertz is applied to monopole microwave radiator (600) having a surface wave limiter (606).
    Type: Grant
    Filed: April 17, 1996
    Date of Patent: May 18, 1999
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: G. Dickey Arndt, James R. Carl, George W. Raffoul, Antonio Pacifico
  • Patent number: 5882937
    Abstract: Ammonia monitor and method of use are disclosed. A continuous, real-time determination of the concentration of ammonia in an aqueous process stream is possible over a wide dynamic range of concentrations. No reagents are required because pH is controlled by an in-line solid-phase base. Ammonia is selectively transported across a membrane from the process stream to an analytical stream under pH control. The specific electrical conductance of the analytical stream is measured and used to determine the concentration of ammonia.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: March 16, 1999
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Richard L. Sauer, James R. Akse, John O. Thompson, James E. Atwater
  • Patent number: 5879079
    Abstract: An automated propellant blending apparatus and method uses closely metered addition of countersolvent to a binder solution with propellant particles dispersed therein to precisely control binder precipitation and particle aggregation. A profile of binder precipitation versus countersolvent-solvent ratio is established empirically and used in a computer algorithm to establish countersolvent addition parameters near the cloud point for controlling the transition of properties of the binder during agglomeration and finishing of the propellant composition particles. The system is remotely operated by computer for safety, reliability and improved product properties, and also increases product output.
    Type: Grant
    Filed: August 20, 1997
    Date of Patent: March 9, 1999
    Assignee: The United States of America as represented by the Administrator, of the National Aeronautics and Space Administration
    Inventors: Carl W. Hohmann, Douglas W. Harrington, Maureen L. Dutton, Billy Charles Tipton, Jr., James W. Bacak, Frank Salazar
  • Patent number: 5866007
    Abstract: The present invention provides a method and apparatus for separating a blood sample having a volume of up to about 20 milliliters into cellular and acellular fractions. The apparatus includes a housing divided by a fibrous filter into a blood sample collection chamber having a volume of at least about 1 milliliter and a serum sample collection chamber. The fibrous filter has a pore size of less than about 3 microns, and is coated with a mixture including between about 1-40 wt/vol % mannitol and between about 0.1-15 wt/vol % of plasma fraction protein (or an animal or vegetable equivalent thereof). The coating causes the cellular fraction to be trapped by the small pores, leaving the cellular fraction intact on the fibrous filter while the acellular fraction passes through the filter for collection in unaltered form from the serum sample collection chamber.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: February 2, 1999
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Peggy A. Whitson, Vaughan L. Clift
  • Patent number: 5807007
    Abstract: Misalignment accommodating connector assembly for removably connecting first and second objects which may comprise: a first connector subassembly (10) having an arm member (11) extending therefrom transversely through which is provided a tubular member (12); a second connector subassembly (20) having a pair of spaced apart arm members (21,22) each of which is provided with a transversely disposed coaxially aligned semi-cylindrical recess (24,25) for receiving opposite ends of the first connector tubular member (12) upon lateral insertion of the first connector arm member (11) into the space (23) between the second connector pair of arm members (21,22).
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: September 15, 1998
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Jack S. Stemper
  • Patent number: 5798261
    Abstract: A method for making a biocompatible polymer article using a uniform atomic oxygen treatment is disclosed. The substrate may be subsequently optionally grated with a compatibilizing compound. Compatibilizing compounds may include proteins, phosphorylcholine groups, platelet adhesion preventing polymers, albumin adhesion promoters, and the like. The compatibilized substrate may also have a living cell layer adhered thereto. The atomic oxygen is preferably produced by a flowing afterglow microwave discharge, wherein the substrate resides in a sidearm out of the plasma. Also, methods for culturing cells for various purposes using the various membranes are disclosed as well. Also disclosed are porous organic polymers having a distributed pore chemistry (DPC) comprising hydrophilic and hydrophobic regions, and a method for making the DPC by exposing the polymer to atomic oxygen wherein the rate of hydrophilization is greater than the rate of mass loss.
    Type: Grant
    Filed: June 3, 1994
    Date of Patent: August 25, 1998
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Steven L. Koontz
  • Patent number: 5792621
    Abstract: A "reagentless" chemiluminescent biosensor and method for the determination of hydrogen peroxide, ethanol and D-glucose in water. An aqueous stream is basified by passing it through a solid phase base bed. Luminol is then dissolved in the basified effluent at a controlled rate. Oxidation of the luminol is catalyzed by the target chemical to produce emitted light. The intensity of the emitted light is detected as a measure of the target chemical concentration in the aqueous stream. The emitted light can be transmitted by a fiber optic bundle to a remote location from the aqueous stream for a remote reading of the target chemical concentration.
    Type: Grant
    Filed: June 28, 1995
    Date of Patent: August 11, 1998
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Charles E. Verostko, James E. Atwater, James R. Akse, Jeffrey L. DeHart, Richard R. Wheeler