Abstract: An example device includes processing circuitry configured to receive, from an oxygen sensor, an ambient air signal indicative of an oxygen partial pressure of ambient air. The processing circuitry is further configured to receive, from an atmospheric pressure sensor, an atmospheric pressure sensor signal indicative of atmospheric pressure. The processing circuitry is configured to determine, based on the atmospheric pressure sensor signal, an oxygen partial pressure of the ambient air, determine, based at least in part on the oxygen partial pressure of the ambient air and the ambient air signal, the one or more calibration parameters, and calibrate, based on the one or more calibration parameters, the oxygen sensor. The calibrated oxygen sensor may be used to, for example, determine the oxygen content of urine of a patient to monitor renal function of the patient.

Abstract: Example devices and techniques for sensing a parameter of a substance of interest are disclosed. An example catheter includes an elongated body defining a lumen. The lumen is configured to receive or house an oxygen sensing element. When the oxygen sensing element is located in a proximal portion of the lumen, the oxygen sensing element is configured to sense an amount of dissolved oxygen in a fluid external to the lumen. The catheter is configured to block ingress of the fluid into the lumen while the oxygen sensing element senses the amount of dissolved oxygen.

Abstract: An example device includes memory and processing circuitry communicatively coupled to the memory. The processing circuitry is configured to determine a first baseline value of dissolved oxygen in a fluid and determine a second baseline value of a total oxygen output in the fluid. The processing circuitry is also configured to receive, from a first sensor, a first signal indicative of an amount of dissolved oxygen in the fluid and receive, from a second sensor, a second signal indicative of the output of the fluid. The processing circuitry is configured to determine a risk of developing acute kidney injury (AKI) based at least in part on the first baseline value, the second baseline value, the first signal, and the second signal.

Abstract: An example device includes memory configured to store an observer and processing circuitry communicatively coupled to the memory. The processing circuitry is configured to receive, from an oxygen sensor, an oxygen sensor signal indicative of an amount of dissolved oxygen in a fluid, wherein the oxygen sensor is located in a distal portion of a catheter or distal to a distal end of the catheter, and wherein the fluid flows to the oxygen sensor from a location within a patient. The processing circuitry is configured to determine, based on the oxygen sensor signal, a measurement of the amount of dissolved oxygen in the fluid. The processing circuitry is configured to apply the observer to the measurement of the amount of dissolved oxygen in the fluid. The processing circuitry is configured to determine, based on the observer, an estimate of an amount of dissolved oxygen in the fluid at the location.

Abstract: An example device includes an elongated body defining a lumen, the elongated body comprising a proximal portion and a distal portion; and one or more sensors configured to: stimulate a fluorescence response from one or more fluorescent probes released into a fluid and flowing with the fluid through the lumen; and detect the fluorescence response, wherein the fluorescence response is indicative of a composition of the fluid.

Abstract: An example system includes an elongated body, a fluorescent material, and a diffuse reflector. The elongated body defines a lumen and includes a proximal portion and a distal portion. The fluorescent material is configured to be in fluid communication with a fluid in the lumen. The diffuse reflector is configured to diffuse excitation light received from an excitation light source and direct the diffused excitation light toward the fluorescent material and diffuse the fluoresced light received from the fluorescence material and direct the fluoresced light toward a fluorescent light detector.

Abstract: A device for measuring oxygen saturation includes circuitry configured to determine a measured difference of forward voltage based on a first forward voltage at a first light emitting diode and a second forward voltage a second light emitting diode and determine that the first and second light emitting diodes are valid based on a calibrated difference of forward voltage and the measured difference of forward voltage. In response to the determination that the first and second light emitting diodes are valid, the circuitry is configured to determine an oxygen saturation level.

Abstract: Advanced interconnect technologies such as Through Silicon Vias (TSVs) have become an integral part of 3-D integration. Methods and systems and provided for laser-based acoustic techniques in which a short laser pulse generates broadband acoustic waves that propagate in the TSV structure. An optical interferometer detects the surface displacement caused by the acoustic waves reflecting within the structure as well as other acoustic waves traveling near the surface that has information about the structure dimensions and irregularities, such as voids. Features of voids, such as their location, are also identified based on the characteristics of the acoustic wave as it propagates through the via. Measurements typically take few seconds per site and can be easily adopted for in-line process monitoring.

Abstract: Advanced interconnect technologies such as Through Silicon Vias (TSVs) have become an integral part of 3-D integration. Methods and systems and provided for laser-based acoustic techniques in which a short laser pulse generates broadband acoustic waves that propagate in the TSV structure. An optical interferometer detects the surface displacement caused by the acoustic waves reflecting within the structure as well as other acoustic waves traveling near the surface that has information about the structure dimensions and irregularities, such as voids. Features of voids, such as their location, are also identified based on the characteristics of the acoustic wave as it propagates through the via. Measurements typically take few seconds per site and can be easily adopted for in-line process monitoring.