Patents Assigned to Metropolitan Water District of Southern California
  • Patent number: 6436638
    Abstract: A method for selectively detecting the presence of C. parvum organisms in a sample. A method for selectively detecting the presence of C. parvum organisms and for detecting the presence of G. lamblia organisms, simultaneously, in a sample. A method for selectively detecting viable C. parvum organisms in a sample potentially containing viable C. parvum organisms. A method for selectively detecting viable C. parvum organisms and for detecting viable G. lamblia organisms, simultaneously. A method for selectively detecting infectious C. parvum organisms in a sample, and in another embodiment, additionally comprising detecting viable G. lamblia organisms in the sample, simultaneously. Kit for use in performing these methods.
    Type: Grant
    Filed: June 4, 1999
    Date of Patent: August 20, 2002
    Assignee: Metropolitan Water District of Southern California
    Inventors: Ricardo De Leon, Paul A. Rochelle
  • Patent number: 5996413
    Abstract: A method is provided for testing prestressed concrete pipe. In the method, elastic waves are serially induced at at least three different inducing locations along the surface of the conduit. The shear wave component of each induced elastic wave is detected by at least one, and preferably two, acoustic sensors disposed at fixed sensing sites along the conduit. The relationship between at least one parameter of each induced shear wave and the distance between each inducing location and the acoustic sensor(s), are correlated and compared with standard correlations to identify structural discontinuities in the conduit. In a typical example of the method, elastic waves are induced using a mechanical hammer at multiple inducing sites around a multiplicity of annuli along the length of the conduit. Each annulus is separated from adjoining annuli by 2-4 feet.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: December 7, 1999
    Assignee: The Metropolitan Water District of Southern California
    Inventors: Subramanian T. M. Iyer, Harvey O. Webster, III
  • Patent number: 5770368
    Abstract: The subject invention provides processes and kits for detecting encysted forms of protozoa, particularly Cryptosporidium and Giardia, that are viable and infectious. To determine viability, cysts or oocysts are heated to a temperature that induces transcription of heat shock protein (HSP) genes. Alternatively, to determine infectivity the encysted forms are inoculated onto susceptible cell cultures. The viability or infectivity of the encysted forms can be determined by synthesizing a cDNA from an induced HSP RNA template using a primer that is specific for particular genus or species of protozoa, followed by enzymatic amplification of the cDNA. Alternatively, infectivity can be determined by amplifying HSP DNA from infected cells using a primer pair that is specific for a particular genus or species of protozoa. Amplified HSP DNA can be detected using probes that are specific for a protozoan species of interest, such as the human pathogens C. parvum and G. lamblia.
    Type: Grant
    Filed: May 9, 1996
    Date of Patent: June 23, 1998
    Assignee: Metropolitan Water District of Southern California
    Inventors: Ricardo De Leon, Paul A. Rochelle