Patents by Inventor David E. Townsend

David E. Townsend has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7560246
    Abstract: The present invention relates generally to compositions and methods for detecting target microorganisms in a sample. In particular, the present invention relates to compositions comprising a conditionally detectable maker and an enzyme substrate that provides detection of the target microorganism as well as methods of use thereof. With the invention disclosed herein, a widely applicable approach is revealed which utilizes a presumptive indicator for the target microorganism and non-target microorganisms capable of growth and detection in a medium followed by a confirmation indicator, which is substantially only reacted upon by the non-target microorganisms.
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: July 14, 2009
    Assignee: BioControl Systems, Inc.
    Inventor: David E Townsend
  • Patent number: 7122338
    Abstract: Methods for the detection and/or quantification of a biological material in a sample. The method includes the steps of liquefying the sample (if necessary) and pouring the liquefied sample into the incubation vessel. The incubation vessel has a generally flat horizontal surface and the surface is divided into at least one incubation site. Each incubation site is adapted to hold an aliquot of liquid and is sized and shaped, and formed of a suitable material, to hold the aliquot within the well by surface tension. Any excess liquid from the liquefied sample is poured from the surface of the incubation vessel. The method then involves incubating that incubation vessel until the presence or absence of the biological material is determined. The presence of air bubbles can be dramatically reduced by the presence of a surface acting agent in the liquid sample deposited on the device surface.
    Type: Grant
    Filed: January 21, 2003
    Date of Patent: October 17, 2006
    Assignee: Biocontrol Systems, Inc.
    Inventors: Andrew J. Crouteau, Mark W. Pierson, David E. Townsend, Ali Naqui
  • Publication number: 20040018585
    Abstract: Methods for the detection and/or quantification of a biological material in a sample. The method includes the steps of liquefying the sample (if necessary) and pouring the liquefied sample into the incubation vessel. The incubation vessel has a generally flat horizontal surface and the surface is divided into at least one incubation site. Each incubation site is adapted to hold an aliquot of liquid and is sized and shaped, and formed of a suitable material, to hold the aliquot within the well by surface tension. Any excess liquid from the liquefied sample is poured from the surface of the incubation vessel. The method then involves incubating that incubation vessel until the presence or absence of the biological material is determined. The presence of air bubbles can be dramatically reduced by the presence of a surface acting agent in the liquid sample deposited on the device surface.
    Type: Application
    Filed: January 21, 2003
    Publication date: January 29, 2004
    Inventors: Andrew J. Crouteau, Mark W. Pierson, David E. Townsend, Ali Naqui
  • Patent number: 6509168
    Abstract: Method for detection of a biological material in a sample. The method includes the steps of liquifying the sample (if necessary) and pouring the liquified sample into the incubation plate. The incubation plate has a generally flat horizontal surface and the surface is divided into a plurality of at least 20 recessed wells. Each well is adapted to hold an aliquot of liquid and is sized and shaped, and formed of a suitable material, to hold the aliquot within the well by surface tension. Any excess liquid from the liquified sample is poured from the surface of the plate. The method then involves incubating that incubation plate until the presence or absence of the biological material is determined.
    Type: Grant
    Filed: April 18, 2001
    Date of Patent: January 21, 2003
    Assignee: Biocontrol Systems, Inc.
    Inventors: Andrew J. Croteau, Mark W. Pierson, David E. Townsend, Ali Naqui
  • Patent number: 6472167
    Abstract: This invention relates to a method for detecting the existence or measuring the concentration of total viable bacteria in a test sample from a food product. A medium is provided which contains three or more different enzyme substrates each having a nutrient moiety and a detectable moiety linked together. When a substrate is hydrolysed by a bacterial enzyme to create a separate detectable moiety, it causes or produces a detectable signal. These substrates produce detectable signals when any one of a phosphatase enzyme, a glycosidase enzyme or a peptidase enzyme is present in the medium.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: October 29, 2002
    Assignee: BioControl Systems, Inc.
    Inventors: David E. Townsend, Chun-ming Chen
  • Publication number: 20020058298
    Abstract: The present invention relates generally to compositions and methods for detecting target microorganisms in a sample. In particular, the present invention relates to compositions comprising a conditionally detectable maker and an enzyme substrate that provides detection of the target microorganism as well as methods of use thereof. With the invention disclosed herein, a widely applicable approach is revealed which utilizes a presumptive indicator for the target microorganism and non-target microorganisms capable of growth and detection in a medium followed by a confirmation indicator, which is substantially only reacted upon by the non-target microorganisms.
    Type: Application
    Filed: August 27, 2001
    Publication date: May 16, 2002
    Applicant: BioControl System, Inc.
    Inventor: David E. Townsend
  • Patent number: 6387650
    Abstract: This invention relates to a method for detecting the existence or measuring the concentration of total viable bacteria in a test sample from a food product. A medium is provided which contains three or more different enzyme substrates each having a nutrient moiety and a detectable moiety linked together. When a substrate is hydrolyzed by a bacterial enzyme to create a separate detectable moiety, it causes or produces a detectable signal. These substrates produce detectable signals when any one of a phosphatase enzyme, a glycosidase enzyme or a peptidase enzyme is present in the medium.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 14, 2002
    Assignee: Biocontrol Systems, Inc.
    Inventors: David E. Townsend, Chun-ming Chen
  • Publication number: 20020031796
    Abstract: This invention relates to a method for detecting the existence or measuring the concentration of total viable bacteria in a test sample from a food product. A medium is provided which contains three or more different enzyme substrates each having a nutrient moiety and a detectable moiety linked together. When a substrate is hydrolysed by a bacterial enzyme to create a separate detectable moiety, it causes or produces a detectable signal. These substrates produce detectable signals when any one of a phosphatase enzyme, a glycosidase enzyme or a peptidase enzyme is present in the medium.
    Type: Application
    Filed: August 6, 2001
    Publication date: March 14, 2002
    Applicant: Biocontrol Systems, Inc.
    Inventors: David E. Townsend, Chun-Ming Chen
  • Publication number: 20020009766
    Abstract: Method for detection of a biological material in a sample. The method includes the steps of liquifying the sample (if necessary) and pouring the liquified sample into the incubation plate. The incubation plate has a generally flat horizontal surface and the surface is divided into a plurality of at least 20 recessed wells. Each well is adapted to hold an aliquot of liquid and is sized and shaped, and formed of a suitable material, to hold the aliquot within the well by surface tension. Any excess liquid from the liquified sample is poured from the surface of the plate. The method then involves incubating that incubation plate until the presence or absence of the biological material is determined.
    Type: Application
    Filed: April 18, 2001
    Publication date: January 24, 2002
    Applicant: BioControl Systems, Inc.
    Inventors: Andrew J. Croteau, Mark W. Pierson, David E. Townsend, Ali Naqui
  • Patent number: 6287797
    Abstract: Method for detection of a biological material in a sample. The method includes the steps of liquifying the sample (if necessary) and pouring the liquified sample into the incubation plate. The incubation plate has a generally flat horizontal surface and the surface is divided into a plurality of at least 20 recessed wells. Each well is adapted to hold an aliquot of liquid and is sized and shaped, and formed of a suitable material, to hold the aliquot within the well by surface tension. Any excess liquid from the liquified sample is poured from the surface of the plate. The method then involves incubating that incubation plate until the presence or absence of the biological material is determined.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: September 11, 2001
    Assignee: BioControl Systems, Inc.
    Inventors: Andrew J. Croteau, Mark W. Pierson, David E. Townsend, Ali Naqui
  • Patent number: 5985594
    Abstract: Method for detection of a biological material in a sample. The method includes the steps of liquifying the sample (if necessary) and pouring the liquified sample into the incubation plate. The incubation plate has a generally flat horizontal surface and the surface is divided into a plurality of at least 20 recessed wells. Each well is adapted to hold an aliquot of liquid and is sized and shaped, and formed of a suitable material, to hold the aliquot within the well by surface tension. Any excess liquid from the liquified sample is poured from the surface of the plate. The method then involves incubating that incubation plate until the presence or absence of the biological material is determined.
    Type: Grant
    Filed: November 6, 1996
    Date of Patent: November 16, 1999
    Assignee: Idexx Laboratories, Inc.
    Inventors: Andrew J. Croteau, Mark W. Pierson, David E. Townsend, Ali Naqui
  • Patent number: 5700655
    Abstract: Method for detection of a biological material in a sample. The method includes the steps of liquifying the sample (if necessary) and pouring the liquified sample into the incubation plate. The incubation plate has a generally flat horizontal surface and the surface is divided into a plurality of at least 20 recessed wells. Each well is adapted to hold an aliquot of liquid and is sized and shaped, and formed of a suitable material, to hold the aliquot within the well by surface tension. Any excess liquid from the liquified sample is poured from the surface of the plate. The method then involves incubating that incubation plate until the presence or absence of the biological material is determined.
    Type: Grant
    Filed: February 23, 1996
    Date of Patent: December 23, 1997
    Assignee: Idexx Laboratories, Inc.
    Inventors: Andrew J. Croteau, Mark W. Pierson, David E. Townsend, Ali Naqui
  • Patent number: 5610029
    Abstract: The invention features a medium for the detection of target microbes in a liquified environmental or biological sample in less than 18 hours.
    Type: Grant
    Filed: April 18, 1995
    Date of Patent: March 11, 1997
    Assignee: Idexx Laboratories, Inc.
    Inventors: Elizabeth Ehrenfeld, Colin Fricker, David E. Townsend
  • Patent number: 4730628
    Abstract: Cigarette rods include four segments of smokable material. First and second segments are positioned at the extreme ends of the rod. The first segment is positioned at the end of the rod to be lit. A third segment is positioned adjacent the first segment, and a fourth segment is positioned adjacent the second segment. The density of the third segment is greater than the fourth segment. The first and second segments can be "dense ends" or "loose ends" relative to the respective adjacent segments. The cigarette rods have a relatively uniform burn rate provided by treatment of the wrapping material of the rod with burn rate suppressants and burn rate accelerators in the positions thereof which overlie the third and fourth segments, respectively.
    Type: Grant
    Filed: July 21, 1986
    Date of Patent: March 15, 1988
    Assignee: R. J. Reynolds Tobacco Company
    Inventors: David E. Townsend, Thomas A. Perfetti
  • Patent number: 4700726
    Abstract: Cigarette rods include four segments of smokable material. First and second segments are positioned at the extreme ends of the rod. The first segment is positioned at the end of the rod to be lit. A third segment is positioned adjacent the first segments, and a fourth segment is positioned adjacent the second segment. The density of the third segment is greater than the fourth segment. The first and second segments can be "dense ends" or "loose ends" relative to the respective adjacent segments.
    Type: Grant
    Filed: May 2, 1986
    Date of Patent: October 20, 1987
    Assignee: R. J. Reynolds Tobacco Company
    Inventors: David E. Townsend, Diane R. Frye, Tammie B. Greene, Thomas A. Perfetti
  • Patent number: 4595024
    Abstract: A cigarette, having a tobacco rod consisting of at least two segments. The segment toward the filter end of the tobacco rod has a density at least 20% greater than the fire-end segment. The density differential may be combined with a nicotine differential, such that the fire-end segment has a higher nicotine content than does the filter-end segment. This configuration alters the nicotine delivery of the invention, providing a nicotine delivery either uniform during the last half of the cigarette or at levels reduced from those seen during the first few puffs.
    Type: Grant
    Filed: August 31, 1984
    Date of Patent: June 17, 1986
    Assignee: R. J. Reynolds Tobacco Company
    Inventors: Tammie B. Greene, David E. Townsend, Thomas A. Perfetti