Abstract: A method of calibrating a gas sensor comprises determining a sensitivity of a gas sensor to one or more conditions proximate the gas sensor, determining one or more initial calibration factors comprising a sensitivity of the gas sensor to one or more analytes of interest, determining a current sensitivity of the gas sensor to the one or more conditions proximate the gas sensor by measuring a response of the gas sensor while the one or more conditions proximate the gas sensor varies during operation of the gas sensor, and adjusting the one or more initial calibration factors of the gas sensor based, at least in part on the current sensitivity of the gas sensor to the one or more conditions proximate the gas sensor, and a relationship between the sensitivity of the gas sensor to the one or more analytes of interest to the sensitivity of the gas sensor to the one or more conditions proximate the gas sensor.

Abstract: A system for determining one or more properties of one or more gases. The system comprises sensors configured to measure thermal conductivity and exothermic responses of a sample at multiple temperatures. Sensor responses to exposure to a gas sample at two or more temperatures are compensated and analyzed by a subsystem. The subsystem is configured to determine a thermal conductivity of the gas sample at each of the two or more temperatures and determine at least one component of the gas sample based at least in part on the thermal conductivity value of the sample at each of the two or more temperatures. Related systems and methods of determining one or more properties of a sample are also disclosed.

Abstract: Disclosed are methods and devices for detecting retained surgical items or other objects having a magnetic signature within a corpus of a patient. The device can comprise a handle, a shaft extending from the handle, and a distal sensing portion positioned distally of the shaft. The distal sensing portion can comprise one or more gradiometers comprising a plurality of magnetometers. The device can further comprise one or more output components configured to generate a user output to alert a user of a detected object.

Abstract: A system for determining one or more properties of one or more gases. The system comprises sensors configured to measure thermal conductivity and exothermic responses of a sample at multiple temperatures. Sensor responses to exposure to a gas sample at two or more temperatures are compensated and analyzed by a subsystem. The subsystem is configured to determine a thermal conductivity of the gas sample at each of the two or more temperatures and determine at least one component of the gas sample based at least in part on the thermal conductivity value of the sample at each of the two or more temperatures. Related systems and methods of determining one or more properties of a sample are also disclosed.

Abstract: A method of calibrating a gas sensor comprises determining a sensitivity of a gas sensor to one or more conditions proximate the gas sensor, determining one or more initial calibration factors comprising a sensitivity of the gas sensor to one or more analytes of interest, determining a current sensitivity of the gas sensor to the one or more conditions proximate the gas sensor by measuring a response of the gas sensor while the one or more conditions proximate the gas sensor varies during operation of the gas sensor, and adjusting the one or more initial calibration factors of the gas sensor based, at least in part on the current sensitivity of the gas sensor to the one or more conditions proximate the gas sensor, and a relationship between the sensitivity of the gas sensor to the one or more analytes of interest to the sensitivity of the gas sensor to the one or more conditions proximate the gas sensor.

Abstract: Disclosed are methods and devices for detecting retained surgical items or other objects having a magnetic signature within a corpus of a patient. The device can comprise a handle, a shaft extending from the handle, and a distal sensing portion positioned distally of the shaft. The distal sensing portion can comprise one or more gradiometers comprising a plurality of magnetometers. The device can further comprise one or more output components configured to generate a user output to alert a user of a detected object.

Abstract: A system for determining one or more properties of one or more gases. The system comprises sensors configured to measure thermal conductivity and exothermic responses of a sample at multiple temperatures. Sensor responses to exposure to a gas sample at two or more temperatures are compensated and analyzed by a subsystem. The subsystem is configured to determine a thermal conductivity of the gas sample at each of the two or more temperatures and determine at least one component of the gas sample based at least in part on the thermal conductivity value of the sample at each of the two or more temperatures. Related systems and methods of determining one or more properties of a sample are also disclosed.

Abstract: A system for determining one or more properties of one or more gases. The system comprises sensors configured to measure thermal conductivity and exothermic responses of a sample at multiple temperatures. Sensor responses to exposure to a gas sample at two or more temperatures are compensated and analyzed by a subsystem. The subsystem is configured to determine a thermal conductivity of the gas sample at each of the two or more temperatures and determine at least one component of the gas sample based at least in part on the thermal conductivity value of the sample at each of the two or more temperatures. Related systems and methods of determining one or more properties of a sample are also disclosed.

Abstract: Disclosed are methods and devices for detecting retained surgical items or other objects having a magnetic signature within a corpus of a patient. The device can comprise a handle, a shaft extending from the handle, and a distal sensing portion positioned distally of the shaft. The distal sensing portion can comprise one or more gradiometers comprising a plurality of magnetometers. The device can further comprise one or more output components configured to generate a user output to alert a user of a detected object.

Abstract: A system for determining one or more properties of one or more gases. The system comprises sensors configured to measure thermal conductivity and exothermic responses of a sample at multiple temperatures. Sensor responses to exposure to a gas sample at two or more temperatures are compensated and analyzed by a subsystem. The subsystem is configured to determine a thermal conductivity of the gas sample at each of the two or more temperatures and determine at least one component of the gas sample based at least in part on the thermal conductivity value of the sample at each of the two or more temperatures. Related systems and methods of determining one or more properties of a sample are also disclosed.

Abstract: A system for determining one or more properties of one or more gases. The system comprises sensors configured to measure thermal conductivity and exothermic responses of a sample at multiple temperatures. Sensor responses to exposure to a gas sample at two or more temperatures are compensated and analyzed by a subsystem. The subsystem is configured to determine a thermal conductivity of the gas sample at each of the two or more temperatures and determine at least one component of the gas sample based at least in part on the thermal conductivity value of the sample at each of the two or more temperatures. Related systems and methods of determining one or more properties of a sample are also disclosed.

Abstract: In one embodiment, the present disclosure provides a target or mold having one or more support arms coupled to a substrate. The support arm can be used in handling or positioning a target. In another embodiment, the present disclosure provides target molds, targets produced using such molds, and a method for producing the targets and molds. In various implementations, the targets are formed in a number of disclosed shapes, including a funnel cone, a funnel cone having an extended neck, those having Gaussian-profile, a cup, a target having embedded metal slugs, metal dotted foils, wedges, metal stacks, a Winston collector having a hemispherical apex, and a Winston collector having an apex aperture. In yet another embodiment, the present disclosure provides a target mounting and alignment system.

Abstract: A system for determining one or more properties of one or more gases. The system comprises sensors configured to measure thermal conductivity and exothermic responses of a sample at multiple temperatures. Sensor responses to exposure to a gas sample at two or more temperatures are compensated and analyzed by a subsystem. The subsystem is configured to determine a thermal conductivity of the gas sample at each of the two or more temperatures and determine at least one component of the gas sample based at least in part on the thermal conductivity value of the sample at each of the two or more temperatures. Related systems and methods of determining one or more properties of a sample are also disclosed.

Abstract: A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Abstract: A pre-smoke detector and system for use in early detection of developing fires whereby vapors of marker chemicals generated during the melting and/or smoldering of common household materials are detected before detection by conventional smoke detectors. Vapors resulting from heating and resultant vaporization of substances are detected as well as vapors resulting from their breakdown, decomposition, or pyrolysis during the pre-combustion stage. Conventional smoke detectors focus on particle detection and are most effective after a developing fire has produced smoke. To minimize false alarms caused by common household odors, the pre-smoke detectors focus on detecting medium temperature pyrolysis products using sensor coatings that can be consistent with a 10-year operational lifetime and multiple orthogonal detection processes.

Abstract: The invention provides a liquid cell for an atomic force microscope. The liquid cell includes a liquid cell housing with an internal cavity to contain a fluid, a plurality of conductive feedthroughs traversing the liquid cell housing between the internal cavity and a dry side of the liquid cell, a cantilevered probe coupled to the liquid cell housing, and a piezoelectric drive element disposed on the cantilevered probe. The cantilevered probe is actuated when a drive voltage is applied to the piezoelectric drive element through at least one of the conductive feedthroughs. A method of imaging an object in a liquid medium and a method of sensing a target species with the liquid cell are also disclosed.

Abstract: In particular embodiments, the present disclosure provides targets including a metal layer and defining a hollow inner surface. The hollow inner surface has an internal apex. The distance between at least two opposing points of the internal apex is less than about 15 ?m. In particular examples, the distance is less than about 1 ?m. Particular implementations of the targets are free standing. The targets have a number of disclosed shaped, including cones, pyramids, hemispheres, and capped structures. The present disclosure also provides arrays of such targets. Also provided are methods of forming targets, such as the disclosed targets, using lithographic techniques, such as photolithographic techniques. In particular examples, a target mold is formed from a silicon wafer and then one or more sides of the mold are coated with a target material, such as one or more metals.

Abstract: In one embodiment, the present disclosure provides a target or mold having one or more support arms coupled to a substrate. The support arm can be used in handling or positioning a target, In another embodiment, the present disclosure provides target molds, targets produced using such molds, and a method for producing the targets and molds. In various implementations, the targets are formed in a number of disclosed shapes, including a funnel cone, a funnel cone having an extended neck, those having Gaussian-profile, a cup, a target having embedded metal slugs, metal dotted foils, wedges, metal stacks, a Winston collector having a hemispherical apex, and a Winston collector having an apex aperture. In yet another embodiment, the present disclosure provides a target mounting and alignment system.

Abstract: A pre-smoke detector and system for use in early detection of developing fires whereby vapors of marker chemicals generated during the melting and/or smoldering of common household materials are detected before detection by conventional smoke detectors. Vapors resulting from heating and resultant vaporization of substances are detected as well as vapors resulting from their breakdown, decomposition, or pyrolysis during the pre-combustion stage. Conventional smoke detectors focus on particle detection and are most effective after a developing fire has produced smoke. To minimize false alarms caused by common household odors, the pre-smoke detectors focus on detecting medium temperature pyrolysis products using sensor coatings that can be consistent with a 10-year operational lifetime and multiple orthogonal detection processes.