Abstract: A housing selectively encloses a nozzle. The housing has a body that partially defines an interior space in which the nozzle is configured to be disposed. The housing also includes a cover assembly that selectively blocks a first aperture of the body and further defines the interior space. Additionally, the housing has a piston that is disposed in the interior space and secured to the nozzle. The piston defines a gas inlet, a liquid inlet, and an outlet fluidly connected to both the gas inlet and the liquid inlet. The housing further includes a biasing member attached to the piston. The biasing member is configured to exert a biasing force that biases the nozzle to a retracted position. The biasing member is further configured such that when pressurized gas flows through the body, the biasing force is overcome such that the nozzle is disposed in an extended position.

Abstract: A housing selectively encloses a nozzle. The housing has a body that partially defines an interior space in which the nozzle is configured to be disposed. The housing also includes a cover assembly that selectively blocks a first aperture of the body and further defines the interior space. Additionally, the housing has a piston that is disposed in the interior space and secured to the nozzle. The piston defines a gas inlet, a liquid inlet, and an outlet fluidly connected to both the gas inlet and the liquid inlet. The housing further includes a biasing member attached to the piston. The biasing member is configured to exert a biasing force that biases the nozzle to a retracted position. The biasing member is further configured such that when pressurized gas flows through the body, the biasing force is overcome such that the nozzle is disposed in an extended position.

Abstract: The present invention provides improved flow cytometry tubes containing ports to allow rapid addition and mixing of reagents with sample during flow cytometry. The present invention further provides rapid mixing cytometry devices and method for their use in rapid reagent mixing during flow cytometry.

Abstract: A digital signal processing based feed forward amplifier includes a delay circuit which receives a portion of the input signal and generates a delayed input signal. A first analog to digital converter receives another portion of the input signal and generates a digitized input signal. A main amplifier receives the delayed input signal and generates a main amplified signal. A second analog to digital converter receives at least a portion of the main amplified signal and converts it to a digitized main amplified signal. A digital signal processor receives the digitized input signal and the digitized main amplified signal and generates a digitized error signal. The digitized error signal is converted to an analog error signal by a digital to analog converter. An error amplifier receives the analog error signal and amplifies it to generate an amplified error signal.

Abstract: An RF power amplifier with amplifier stage failure detection comprises an amplifier input for receiving an RF signal to be amplified, an amplifier output for outputting an amplified RF signal, a plurality of separate amplifier stages coupled between the amplifier input and amplifier output so as to cumulatively provide a desired amplifier gain to the input RF signal, and means for detecting amplifier stage failure by providing a pilot tone separately to the amplifier stages based on a separate timing for each stage and detecting pilot tones output from the stages based on the timing.

Abstract: An RF power amplifier with amplifier stage failure detection comprises an amplifier input for receiving an RF signal to be amplified, an amplifier output for outputting an amplified RF signal, a plurality of separate amplifier stages coupled between the amplifier input and amplifier output so as to cumulatively provide a desired amplifier gain to the input RF signal, and means for detecting amplifier stage failure by providing a pilot tone separately to the amplifier stages based on a separate timing for each stage and detecting pilot tones output from the stages based on the timing.

Abstract: An RF power amplifier with amplifier stage failure detection comprises an amplifier input for receiving an RF signal to be amplified, an amplifier output for outputting an amplified RF signal, a plurality of separate amplifier stages coupled between the amplifier input and amplifier output so as to cumulatively provide a desired amplifier gain to the input RF signal, and means for detecting amplifier stage failure by providing a pilot tone to the amplifier stages, duty cycling the amplifier stages based on a separate timing for each stage and detecting the pilot tone output from the stages based on the timing.

Abstract: A narrow band complex input signal, typically having multiple independently modulated carriers, is processed to produce an output signal which, while containing the information in the input signal, is not an amplitude dependent signal, and thus can be transmitted through nonlinear media, such as a saturated power amplifier, as a less expensive and more power-efficient alternative over a conventionally required linear power amplifier. The process separates the multiple input signals into an amplitude-limited angle-modulated carrier component and an envelope component, and then combines these components by a form of pulse-duty-factor modulation such as pulse-duration modulation, at a sufficiently high sampling rate. The combined signal is input to a nonlinear power amplifier. Unwanted sidebands are rejected by bandpass filtering at the amplifier output so as to pass only the carrier and its signal bandwidth.

Abstract: A mold section is made by covering at least the surface of a cavity of a metallic substrate with a layer of plastic barrier material. A pattern is then placed on this so-covered surface. A compressive force and heat are applied to the metallic substrate and pattern causing the material of the layer to flow and then become bonded to the surface of the cavity while duplicating the surface and shape of the pattern.