Patents Assigned to University of British Columbia (UBC)
  • Patent number: 5514882
    Abstract: A new static memory cell based on the bistable operation of a three-terminal four layer semiconductor device working in the forward blocking state is disclosed. The power consumption of the memory cell is low. The switching speed of the memory cell is in the nanosecond range. The memory cell may be integrated into VLSI processes and is of a size suitable for VLSI applications. The memory cell comprises a semiconductor device which comprises: an n-type semiconductor cathode region; a p-type semiconductor gate region; a third semiconductor region adjacent the gate region; a fourth region adjacent the third semiconductor region; and a hole-injecting boundary between the third semiconductor region and the fourth region. The semiconductor device is preferably a p-n-p-n device. The gate current-voltage characteristics of the device comprise a negative resistance region. The device is designed to operate in a forward blocking low current state.
    Type: Grant
    Filed: February 2, 1995
    Date of Patent: May 7, 1996
    Assignee: The University of British Columbia
    Inventor: David D. Shulman
  • Patent number: 5514665
    Abstract: Methods for reducing the risk of or preventing infections by bacterial pathogens in vivo. In particular, a method for reducing the risk of P. aeruginosa infection in vivo in compromised hosts such as cystic fibrosis patients. The methods involve the use of dextran or dextran sulphate as the active ingredient.
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: May 7, 1996
    Assignee: University of British Columbia
    Inventors: David P. Speert, Thomas C. Usher
  • Patent number: 5514848
    Abstract: An electrode structure is composed of a gas passage containing a cathode ending in a cathode tip adjacent one end of the passage and has an anode electrode adjacent to the other end of the passage. A restriction is formed within the passage between the cathode and anode electrode to restrict the cross sectional area of the passage an accelerate the flow of gas from the cathode toward the anode and thereby increase the arc length and permit a reduced amperage to voltage (A/V) ratio for a given power input to the structure.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: May 7, 1996
    Assignee: The University of British Columbia
    Inventors: Douglas A. Ross, Alan Burgess
  • Patent number: 5513100
    Abstract: A force feedback velocity control measures the forces adjacent the end point of an arm being controlled and adjusts the stiffness of a manual controller in any one direction by scaling the end point force in the corresponding direction and adjusting the scaled force based on the degree of displacement of the manual controller away from a datum or zero velocity position in the one direction. A suitable deadband zone is provided surrounding the datum position.
    Type: Grant
    Filed: June 10, 1993
    Date of Patent: April 30, 1996
    Assignee: The University of British Columbia
    Inventors: Niall R. Parker, Peter D. Lawrence, Septimiu E. Salcudean
  • Patent number: 5512675
    Abstract: A method for synthesizing a porphocyanine having the formula: ##STR1## where each R is ethyl, comprises either: (1) treating 3,3'-4,4'-tetraethyl-5,5'-bisaminomethyl-2,2'-dipyrromethane with a 10-fold excess of DDQ or(2) treating 3,3'-4,4'-tetraethyl-5,5'-diformyl 2,2'-dipyrromethane with ammonia, followed by column chromatography purification and evaporating to dryness the eluant containing the purified product.
    Type: Grant
    Filed: June 15, 1993
    Date of Patent: April 30, 1996
    Assignee: The University of British Columbia
    Inventors: Hang Tang, Lily Xie, Tilak Wijesekera, David Dolphin
  • Patent number: 5510044
    Abstract: A composition, adapted to be used in the flotation of ore fractions in aqueous suspension, with the advantages of better dispersability of the amine and improved flotation results. The composition consists essentially of: (a) water; (b) a long chain aliphatic amine; and (c) a frother. The composition may further contain a carboxylic or mineral acid emulsifier.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: April 23, 1996
    Assignee: The University of British Columbia
    Inventors: Janusz S. Laskowski, Qun Wang, Elena A. Alonso
  • Patent number: 5510248
    Abstract: An isolated polynucleotide which encodes human prothrombin is modified to encode amino acid substitutions at positions 155, 271 and 284 of the prothrombin polypeptide. A second polynucleotide is further modified to encode an additional amino acid substitution at residue 320.The polypeptide encoded by the first polynucleotide is resistant to cleavage by thrombin and factor Xa, exhibits greatly reduced procoagulant activity towards fibrinogen and unchanged anticoagulant activity towards protein C. The polypeptide can be cleaved between amino acid positions 320 and 321 to produce an active serine protease which can activate protein C, thereby inhibiting coagulation and stimulating activated protein C fibrinolytic activity.The polypeptide encoded by the second polynucleotide cannot be cleaved, mimics inactive prothrombin and thereby acts as a reversible inhibitor of coagulation by competing with Factor Xa and Factor Va for interaction at the phospholipid surface.
    Type: Grant
    Filed: June 22, 1993
    Date of Patent: April 23, 1996
    Assignee: The University of British Columbia
    Inventors: Helene C. F. Cote, Willem K. Stevens, Michael E. Nesheim, Ross T. A. MacGillivray
  • Patent number: 5507394
    Abstract: A composition, adapted to be used in the flotation of ore fractions in aqueous suspension, consists essentially of: (a) water; (b) a hydrocarbon extender oil, preferably one having a low aromatics content; (c) a long chain aliphatic amine, such as a tallow-based amine, preferably one with an iodine value is less than about 20 cg/g; and (d) an acid emulsifier. This composition is prepared by the following successive steps: (a) dissolution of the amine in the oil at an elevated temperature, (b) addition of the acid to the aqueous phase, (c) addition of the oil containing the amine to the aqueous phase, and (d) emulsification of the mixture using an appropriate shearing.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: April 16, 1996
    Assignee: The University of British Columbia
    Inventors: Janusz S. Laskowski, Oun Wang
  • Patent number: 5506257
    Abstract: The present invention provides methods for blocking sodium channels in cardiac or neuronal tissue using aminocyclohexylamides. This invention also provides kits including aminocyclohexylamides and instructions for the use of the compounds for the treatment of arrhythmia or for the inducement of local anaesthesia.
    Type: Grant
    Filed: February 15, 1994
    Date of Patent: April 9, 1996
    Assignee: University of British Columbia
    Inventors: Bernard A. MacLeod, Michael J. A. Walker, Richard A. Wall
  • Patent number: 5506217
    Abstract: This invention pertains to the synthesis and usc as anti-cancer therapeutic agents of a group of substances with a glycerol backbone linked to phosphonocholinc, or other phosphorus-containing head groups, of the following formula: ##STR1## wherein n is 0 to 14 and R.sub.1 is an alkyl group containing 12 to 20 carbon atoms, R.sub.2 is a methyl group, n=0 to 14 and m=2 to 10, or enantiomer thereof, or mixture of stereoisomers. This invention also pertains to the following formula: ##STR2## wherein n is 15 to 17; R1 is an alkyl group: m is 0 to 2; T is an oxygen atom or a methylene; and R.sub.2 is a choline group and therapeutically effective pharmaceutically acceptable salts thereof. These thiophosphonolipids are useful for treating cancer in a mammal in need of cancer treatment.
    Type: Grant
    Filed: November 10, 1994
    Date of Patent: April 9, 1996
    Assignee: The University of British Columbia
    Inventors: Hassan Salari, Robert Bittman
  • Patent number: 5506221
    Abstract: The invention presents compounds useful for the prevention of inflammatory or allergic reaction or the treatment of cardiovascular or haemodynamic disorders having the formula: ##STR1## where R= ##STR2## where R= ##STR3## or pharmaceutically acceptable acids or salts thereof.
    Type: Grant
    Filed: April 12, 1994
    Date of Patent: April 9, 1996
    Assignees: University of British Columbia, University of Alberta
    Inventors: Raymond J. Andersen, Theresa M. Allen, David L. Burgoyne
  • Patent number: 5500088
    Abstract: The load on a refiner motor is controlled by adjusting the motor load setpoint by monitoring load applied by the refiner and the plate gap between the refiner plates to define the curve of the load versus plate gap relationship. This slope of load versus plate gap relationship is estimated and when the sign of the slope of the curve changes sign indicating operation in an unstable zone of pad collapse and based on the tendency for the refiner to be in the unstable operation zone over a selected period of time exceeding a preset limit adjusting the setpoint lower to approach more closely the maximum load applied over the selected time.
    Type: Grant
    Filed: March 14, 1995
    Date of Patent: March 19, 1996
    Assignees: MacMillan Bloedel Limited, The University of British Columbia
    Inventors: Bruce J. Allison, Joe E. Ciarniello, Guy A. Dumont, Patrick J. Tessier
  • Patent number: 5500353
    Abstract: This invention provides a bacterium having an S-layer modified such that the bacterium S-layer protein gene contains one or more in-frame sequences coding for one or more heterologous polypeptides and, the S-layer is a fusion product of the S-layer protein and the heterologous polypeptide. The bacterium is preferably a Caulobacter which may be cultured as a film in a bioreactor or may be used to present an antigenic epitope to the environment of the bacterium. This invention also provides a method of expressing and presenting to the environment of a Caulobacter, a polypeptide that is heterologous to the S-layer of Caulobacter which comprises cloning a coding sequence for the polypeptide in-frame into an S-layer protein gene of Caulobacter whereby the polypeptide is expressed and presented on the surface of the Caulobacter as a fusion product of the S-layer protein and the polypeptide in the S-layer of the Caulobacter.
    Type: Grant
    Filed: February 9, 1994
    Date of Patent: March 19, 1996
    Assignee: The University of British Columbia
    Inventors: John Smit, Wade H. Bingle
  • Patent number: 5481637
    Abstract: An outer prism light guide surrounds a cover which in turn surrounds a light source. The outer guide is formed of prism light guide wall material having uniform shape in cross-sections perpendicular to a first octature symmetry direction, with its optical center line parallel to the first octature symmetry direction. Surfaces of the wall material are substantially in octature relative to the first octature symmetry direction. A surface normal vector at any point on any internal surface of the material is either substantially parallel or substantially perpendicular to a first notional line extending from the point through and perpendicular to the optical center line. The cover has cylindrical symmetry about the optical center line to intercept a substantial portion of light emitted by the source.
    Type: Grant
    Filed: November 2, 1994
    Date of Patent: January 2, 1996
    Assignee: The University of British Columbia
    Inventor: Lorne A. Whitehead
  • Patent number: 5478366
    Abstract: A pumpable slurry for recovering fuel value from lignin by mixing the lignin with water, fuel oil and a dispersing agent to form a stable thixotropic or near Newtonian portable slurry by coordinating the amounts of lignin, water and fuel oil to produce a substantially slurry suitable for use as a liquid fuel having a viscosity after stirring of 100 to 1,000 mPa.s.
    Type: Grant
    Filed: September 28, 1994
    Date of Patent: December 26, 1995
    Assignee: The University of British Columbia
    Inventors: Khay C. Teo, Alan P. Watkinson
  • Patent number: 5475694
    Abstract: A method of testing a digital integrated circuit for faults. A plurality of n check points l.sub.1, l.sub.2, . . . , l.sub.n are established to define a test sequence. A set of m references r.sub.1, r.sub.2, . . . , r.sub.m are predefined, corresponding to the signatures which the circuit would produce at the corresponding check points in the absence of any faults. A test sequence is applied to the circuit and an output signature s.sub.i is derived from the circuit at the corresponding check point l.sub.i. The output signature is compared with each member of the set of references. The circuit is declared "good" if the signature matches at least one member of the set of references, or "bad" if a signature matches no members of the set of references. Testing proceeds in similar fashion at the next check point, until the circuit has been tested at all check points.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: December 12, 1995
    Assignee: The University of British Columbia
    Inventors: Andre Ivanov, Yuejian Wu
  • Patent number: 5468508
    Abstract: This invention pertains to a novel process for preserving the quality attributes and ascorbic acid content of fresh fruit juices and fruit juice blends. The process involves sanitizing the outer surface of a fruit, extracting the juice from the edible portion of the fruit, gasifying the juice with an oxygen-containing, carbon dioxide-containing gas mixture, filling a high gas-barrier container with the juice; hermetically sealing the container and rapidly cooling the juice in the container. Alternatively, the extracted juice may be filled into the high gas barrier container and then gasified prior to hermetically sealing the container.
    Type: Grant
    Filed: February 11, 1993
    Date of Patent: November 21, 1995
    Assignee: The University of British Columbia
    Inventors: Chiu H. Wu, William D. Powrie
  • Patent number: 5456362
    Abstract: A process for the flotation of coarse potash ore fractions in an aqueous brine containing frother that comprises: (a) using a column flotation device in which air bubbles are generated by a sparger that utilizes high intensity shearing to mix and disperse air into brine containing frother; (b) removing a portion of the suspension at another point in the direction of flow of the suspension to regulate the upward flow rate of the suspension past the point where the air is dispersed into the suspension and thereby reducing fine particles entrainment in the froth product. The suspension can be conditioned with an aqueous composition comprising a hydrocarbon extender oil and a substantially saturated long chain primary mine, optionally comprising an acid, such as a mineral acid or carboxylic acid, to emulsify the oil in the composition, or can be conditioned with an aqueous composition comprising a long chain primary amine having an iodine value ranging from about 20 to about 70 cg/g.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: October 10, 1995
    Assignee: The University of British Columbia
    Inventors: Janusz S. Laskowski, Qun Wang
  • Patent number: 5455212
    Abstract: A method for producing alumina-silicon carbide ceramic powders by in situ production of silicon carbide particles by introducing a pyrolyzable carbon source, preferably a gaseous hydrocarbon, into a reactor containing an alumino-silicate, pyrolyzing the pyrolyzable carbon source to form carbon particles in situ, wherein the carbon particles are capable of reacting with a silicate in the alumino-silicate to form carbide products, and then reacting the silicate and the carbon particles in situ at an effective temperature, preferably at least 1450.degree. C. and more preferably at least 1500.degree. C., for a sufficient time to transform the alumino-silicate and the pyrolyzable carbon source into the composite ceramic powder having alumina (Al.sub.2 O.sub.3) and silicon carbide (SiC) as major phases.
    Type: Grant
    Filed: March 15, 1994
    Date of Patent: October 3, 1995
    Assignee: The University of British Columbia
    Inventors: Asoke C. Das Chaklader, Edmond C. Y. Lin
  • Patent number: 5450498
    Abstract: An electrostatic transducer in which two sheets are separated by a gas-filled gap. The sheets have conductive surfaces for imposing electric fields within the gap when an electrical potential is applied across the sheets. A flexible positioning mechanism between the sheets maintains the gap at a desired time-averaged thickness. The gap is made up of a plurality of thick regions and a plurality of thin regions. Both regions have a total projected area which is a substantial portion of the total area of one of the sheets. The average thickness of the gap in the thick regions is at least ten times greater than the gap's average thickness in the thin regions. The electrostatic field energy of the electric fields is concentrated in the thin regions.
    Type: Grant
    Filed: July 14, 1993
    Date of Patent: September 12, 1995
    Assignee: The University of British Columbia
    Inventor: Lorne A. Whitehead