Abstract: A system, method and device for interrogating a downhole environment in a borehole beneath a surface includes a source of electromagnetic energy, operable to transmit an electromagnetic signal in the borehole, a sensor module, including a passive resonating circuit including a crystal oscillator having a resonant frequency that varies with changes in the condition in the downhole environment to reflect the electromagnetic signal and to modulate the electromagnetic signal in response to a condition in the downhole environment in the borehole and a detector positionable to receive the reflected modulated electromagnetic signal. Embodiments include a power monitor and circuitry configured and arranged to measure an input frequency at a time when an inflection in the applied power is observed.

Abstract: A system, method and device for interrogating a downhole environment in a borehole beneath a surface includes a source of electromagnetic energy, operable to transmit an electromagnetic signal in the borehole, a sensor module, including a passive resonator having a resonant frequency that varies with changes in the condition in the downhole environment to reflect the electromagnetic signal and generates harmonic frequencies in response to a condition in the downhole environment in the borehole and a detector positionable to receive a returned electromagnetic signal. Embodiments include a filter to pass a harmonic of the resonant frequency of the resonating circuit and circuitry configured and arranged to measure the frequency of the harmonic signal.

Abstract: The present invention discloses an improved system for measurement of the liquid flow rate and totalized liquid production of a producing well. In the method of the present invention, liquid production rate in a pumping well is determined by calculation based upon wellbore geometry and continuously monitoring the depth of the fluid level within the wellbore. It is applicable to any pump lifted well where it is possible to shut the pump off periodically. Accuracy is enhanced with this method by properly accounting for pump leakage and where pump leakage is either known or can be estimated within reasonable limits or where it is measured during the pump shut off cycle.

Abstract: A system, method and device may be used to monitor fluid levels in a borehole. The system includes a pulse generator to generate a pulse of electromagnetic energy to propagate along the wellbore towards a surface of the fluid, a detector to detect a portion of the electromagnetic pulse reflected from the surface of the fluid and propagated along the wellbore towards the detector, a processor to analyze detected signals to determine a level of the surface of the fluid. In an embodiment, the system includes a pump controller to control the operation of a pump located in the wellbore based on the fluid surface level.

Abstract: A system, method and device for interrogating a downhole environment in a borehole beneath a surface includes a source of electromagnetic energy, operable to transmit an electromagnetic signal in the borehole, a sensor module, including a passive resonator having a resonant frequency that varies with changes in the condition in the downhole environment to reflect the electromagnetic signal and generates harmonic frequencies in response to a condition in the downhole environment in the borehole and a detector positionable to receive a returned electromagnetic signal. Embodiments include a filter to pass a harmonic of the resonant frequency of the resonating circuit and circuitry configured and arranged to measure the frequency of the harmonic signal.

Abstract: A system, method and device for interrogating a downhole environment in a borehole beneath a surface includes a source of electromagnetic energy, operable to transmit an electromagnetic signal in the borehole, a sensor module, including a passive resonating circuit including a crystal oscillator having a resonant frequency that varies with changes in the condition in the downhole environment to reflect the electromagnetic signal and to modulate the electromagnetic signal in response to a condition in the downhole environment in the borehole and a detector positionable to receive the reflected modulated electromagnetic signal. Embodiments include a power monitor and circuitry configured and arranged to measure an input frequency at a time when an inflection in the applied power is observed.

Abstract: A system, method and device may be used to monitor fluid levels in a borehole. The system includes a pulse generator to generate a pulse of electromagnetic energy to propagate along the wellbore towards a surface of the fluid, a detector to detect a portion of the electromagnetic pulse reflected from the surface of the fluid and propagated along the wellbore towards the detector, a processor to analyze detected signals to determine a level of the surface of the fluid. In an embodiment, the system includes a pump controller to control the operation of a pump located in the wellbore based on the fluid surface level.

Abstract: Immunogenic peptides derived from the ORF1, ORF2, and ORF3 regions of hepatitis E virus (HEV), diagnostic reagents containing the peptide antigens, vaccine compositions containing the antigens, and antibodies which are immunoreactive with the antigens are disclosed.

Abstract: All or part of the DNA sequence of the gene which encodes the S-layer protein of R. prowazekii as illustrated in Sequence ID No. 1 as well as a truncated identical piece of this gene in R. typhi as well as the 5' and 3' noncoding regions can be used for vaccination against typhus and spotted fever rickettsial infection or to diagnose the diseases caused by these bacteria. The invention is also accomplished by the deduced amino acid sequence of the S-layer protein of R. prowazekii derived from the DNA sequence of the encoding gene. Further, the invention includes the peptide or protein products based on all or parts of this gene.