Abstract: Provided is a durable oxygen sensitive probe of sufficient strength to withstand direct tissue pressures in vivo, the probe comprising a sensor chamber within a biocompatible, gas-permeable membrane containing an oxygen sensitive analyte solution producing oxygen quenchable phosphorescence when excited. Further provided is a tissue oxygen detection and measurement system comprising the probe, and methods for use of the probe and the system to directly, rapidly and accurately measure tissue oxygen levels in a patient without reliance on blood vessels or fluid protection of the probe.

Abstract: Provided is a method and system for the rapid and accurate detection of growth and metabolism of a cellular microorganism in a population of microorganisms in a non-liquid, culture medium. Further provided is a gelled culture medium containing a non-toxic, water-soluble, phosphorescent compound which measures oxygen content (partial pressure) of an microorganism also contained therein, by oxygen-dependent quenching of phosphorescence; or the gel contains a fluorescent pH indicator that demonstrates growth of the microorganism by pH-dependent intensity change or wavelength shift in the emission spectrum. Further provided is a system and method for killing undesirable microorganisms or colonies in the culture medium without harming the surrounding microorganisms.

Abstract: A mobile computing device comprises a housing, a memory, a first current source driver, an audio interface and a processing circuit. The housing is configured to be held in a hand during use. The memory is configured to store audio data. The audio interface comprises a first terminal, a second terminal, and a common ground terminal for the first and second terminals. The processing circuit is configured to control the first current source driver to provide a first audio signal on the first terminal based on the audio data.

Abstract: A method of real-time imaging of dissolved oxygen concentration, comprising adding an oxygen-quenched phosphorescent composition to a sample, exciting phosphorescence in the composition by illuminating the sample with pulses of light, detecting phosphorescence intensity as a function of position in the sample at first and second times following exciting pulses of light, determining oxygen concentration from the phosphorescence detected at the first and second times, generating an image of the oxygen concentration as a function of position, and repeating the exciting, detecting, determining, and image generating steps to produce a series of images showing the oxygen concentration varying over time.

Abstract: An electronic device comprises an earpiece speaker, a loudspeaker, and a processing circuit. The processing circuit is configured to receive a wireless telephony audio signal, to separate the audio signal into a first portion and a second portion, the first portion having higher frequency components than the second portion, wherein the processing circuit is configured to provide the first portion of the audio signal to the earpiece speaker and the second portion of the audio signal to the loudspeaker.

Abstract: Light from a small laser diode is inserted in a distal end of a catheter and passed through an optical fiber that is either included in the lumen or incorporated into the wall of an invasive catheter tube during manufacture. The light is selected to be of a wavelength that is minimally absorbed by tissue, preferably in the range from about 620 nm to 1100 nm. 780 nm is preferably used as this is where the tissue absorption is near a minimum. The light passes out the end of the fiber (at the proximal end of the catheter) and through the tissue to the outside of the patient's skin where it is measured. The light pattern is observed by night vision goggles that filter out other frequencies of light. The detected light permits location of the end of the fiber, the positional accuracy depending on the thickness of tissue between the fiber tip and the exterior of the body. The method is highly accurate for small children and for catheters within a few centimeters of the skin surface of adults.

Abstract: The invention provides an improved, reliable and efficient way of measuring the oxygen concentration gradient in a sample by a novel apparatus and accompanying method of calculating linear oxygen concentrations within the sample, permitting diagnostic testing, for example, of the effects of a developmental or metabolic change in a cell or tissue, in vitro or in vivo, in response to disease, injury radiation, or mechanical or chemical intervention, or simply to changed circumstances, or to measure the oxygen permeability of a membrane or plastic. The apparatus in a preferred embodiment comprises a core digital signal processor (DSP), having sufficient memory (RAM and ROM) to perform the necessary calculations, to control output of excitation light from a light source, and to collect phosphorescent lifetime data; and signal processors (A/D and D/A).

Abstract: A method is described for determining the effect of a drug or drugs on an attached culture of cells comprising (i) dissolving the phosphorescent compound, of known or predetermined quenching constant and lifetime at zero oxygen, in a culture medium at a selected temperature comprising an attached culture of test cells; (ii) introducing the drug(s), whose effect on the test cells is to be determined, into the culture medium; (iii) illuminating the culture medium with pulsed or modulated light at a level sufficient to cause the phosphorescent compound to emit measurable phosphorescence; (iv) measuring the emitted phosphorescence; and (v) calculating the phosphorescence lifetime and oxygen concentration gradient in the medium, thereby determining the effect of the drug on the respiration rate of the cells at the selected temperature. Apparatus for carrying out the method is also disclosed.

Abstract: Methods and compounds for the measurement in vivo of oxygen in living tissue. The compounds preferably comprise a substituted porphyrin which is soluble in aqueous solution which is capable of absorbing an amount of energy and subsequently releasing the energy as phosphorescent light. In preferred embodiments, the porphyrin has an absorption band which is at a wavelength in the near infra-red window of living tissue and the phosphorescence is quenched by molecular oxygen according to the Stern-Volmer relationship.

Abstract: A detection device for three-dimensional tissue oxygen measurement in animals and humans comprising an array of fiber optics effective for transmitting emitted phosphorescent light, and further comprising an array of phosphorescent detectors and an excitation light emitter, forming a matrix and effective for sequential introduction of pulses of excitation light from a plurality of sites in said matrix.

Abstract: This invention provides a method for growth detection and identification of microorganisms in a culture medium comprising providing a culture medium comprising a solubilized oxygen-quenchable phosphorescent compound, inoculating said culture medium with a substrate suspected of being associated with one or more microorganism, and detecting microorganism growth and identifying said microorganism by causing said phosphorescent compound to phosphoresce and observing quenching of oxygen in said culture of said compound.

Abstract: An illuminator for use in a darkroom or with scientific instrumentation with several light emitting diodes arranged in a regular array, a transparent structure to house the LED array, two circular end caps to prevent radiation from the end zones, an opaque decorative adhesive film surrounding the outer surface of the cylinder housing, an attachment means comprising hook and loop strips with adhesive backing and a two wire lead originating in a connector to bring power to the LED array.

Abstract: This invention relates to phosphorescent probes effective for oxygen measurement in human or animal tissue comprising a porphyrin chromophore capable of releasing absorbed energy as phosphorescent light and a dendrimer, wherein said porphyrin chromophore comprises the core of the dendrimer.

Abstract: Methods and apparatus for the measurement of oxygen, pH and CO.sub.2 in human and animal tissue is provided, in which the compounds preferably include a chromophore and/or fluorphor capable of absorbing an amount of energy and subsequently releasing the energy as phosphorescent and/or fluorescent light, and wherein the phosphorescence is quenched by molecular oxygen according to the Stern-Volmer relationship, CO.sub.2 is measured by fluorphor which alters fluorescence with pH.

Abstract: The audio system having a master clock, a serial port clocked according to a serial clock from the audio system, a programmable audio functional circuitry programmable and operable at a plurality of sample rates, and a rate selection control logic which sense a ratio between the serial clock and the master clock. The serial clock is derived from the master clock. The rate selection control logic reprograms the audio functional circuitry based on the ratio, to operate at one of the plurality of sample rates in response to a change in the clock rate of the serial clock, such that the audio functional circuitry operates at another of the plurality of sample rates.

Abstract: Apparatus and method for measuring tissue oxygenation using oxygen dependent quenching phosphorescence. The apparatus comprises a phosphorescent probe applied to the surface of the skin; an oxygen impermeable film placed over the probe and the apparatus; a light excitation means for exciting the probe; a heating element for heating the probe; and an analyzer circuit for analyzing the output.

Abstract: A protocol for transferring audio data and control/status data between audio functional units. The protocol involves multiplexing the audio data and control/status data. The multiplexed data is then transferred between a first audio unit and a second audio unit on two wires, each corresponding to the direction of data flow, and according to a clock rate and a synchronization pattern on third and fourth wires respectively.

Abstract: A method for producing a detecting phosphorescent emission from a body portion comprising the following steps: inserting phosphorescent material into the body portion; inserting a needle into said body portion, said needle encasing a light guide for propagating a light signal therethrough, said light signal exciting said phosphorescent material within said body portion so as to produce a phosphorescent emission having a radius of visibility; and collecting the phosphorescent emission using a collector placed proximate to the surface of the body portion. The present invention also encompasses apparatus for inserting an excitation light into a tissue sample comprising: a needle having a light guide extending axially within the needle, the light guide being configured to transmit an excitation light into the body portion, so as to a phosphorescent carrier medium within the tissue sample.

Abstract: A circuit and method for mixing signals from audio sources provide noise reduction by employing a noise gate to selectively attenuate one of the source signals. The noise gate has a low gain state and a unity gain state. The noise gate switches to its unity gain state when a control signal reaches a predefined threshold voltage. The control signal is generated by rectifying and integrating the noisy source audio signal, so that the noise gate enters the unity gain state only when a useful sound occurs. Thus, the noise in the combined audio signal is reduced, without attenuating useful components of the source signals.

Abstract: An system for imaging an oxygen-containing animal includes an illuminating light source 10, optical filters 12, a microscope and an associated epifluorescence attachment 16, a long pass cutoff filter 8, a camera 20, a frame grabber 22, a counter timer board 24, a computer 26 and an analog monitor 28. The light from the flash lamp 10 is passed through the optical filters to remove an unwanted portion of the spectrum, and focused on a sample object 14 through the epifluorescence attachment and phosphorescence is observed through the long pass cutoff filter. The images are collected with the camera and the frame grabber is used to digitize and average frames while the timing of the flash and gating of the camera intensifier is controlled by the counter timer board. The frames are displayed on the analog monitor.