The present invention provides a method for measuring the gastric acidity of a mammal using a .sup.13C-labeled carbonate compound. Specifically, the present invention relates to a method for measuring the gastric acidity of a mammal including the following steps:

(1) using, as a test sample, expired air of a mammalian subject excreted at any point in time within 30 minutes after oral administration of a predetermined amount of a .sup.13C-labeled carbonate compound, measuring behavior of .sup.13CO.sub.2 in the expired air;

(2) comparing the behavior of .sup.13CO.sub.2 (measured .sup.13CO.sub.2 behavior) obtained in step (1) with the behavior of corresponding .sup.13CO.sub.2 (reference .sup.13CO.sub.2 behavior) that has been obtained beforehand in a control mammal; and

(3) determining the gastric acidity of the mammalian subject based on a difference between the reference .sup.13CO.sub.2 behavior and the measured .sup.13CO.sub.2 behavior obtained above.

There is disclosed a method and system for determining the partial pressure of at least one gas in a mixture of gasses contained in a pressure vessel, the mixture being pressurised to a level which is above local atmospheric pressure. The method comprises the steps of positioning a gas analysis sensor (14) within a pressure vessel (10); exposing the sensor to the mixture of gasses at the pressure level found in the pressure vessel; operating the sensor to measure the actual partial pressure of the at least one gas in the mixture contained in the vessel; and periodically calibrating the sensor by directing a calibrating gas mixture (20, 22) to the sensor in the chamber, the calibrating gas mixture being breathable by a human being.

The invention relates to a device and to a method for continuously measuring the hydrogen sulfide concentration of an off-gas by means of a detachable device suitable for being temporarily connected to equipment producing the off-gas. The method comprises a step of measuring the absorption of electromagnetic radiation by the off-gas. The device and method method can be used in particular to measure the hydrogen sulfide concentration in an off-gas produced during a step of sulfiding a hydroprocessing catalyst.

Embodiments of the present invention relate to freshness indication. In some embodiments, a freshness indicating device is provided. The freshness indicating device comprises a collector and an indicator. The collector is adapted to collect water from an object. The object includes at least one of fruits and vegetables. The indicator is adapted to indicate the freshness of the object based on the amount of the collected water. A corresponding method and a container comprising the freshness indicating device are disclosed as well.

A system for measuring chlorophyll concentration in a leaf sample includes a leaf-holding illuminator device with a main body containing a power source, a plurality of switchable light sources emitting light at different spectra (e.g., red and white light from a broadband light source), and a cap detachably secured to the main body using one or more fastening means. The leaf sample is interposed between the main body and the cap and held in place during imaging. The system includes a mobile electronic device having a camera configured to capture an image of the leaf illuminated by the plurality of switchable light sources, the mobile electronic device having wireless connectivity to a network and an application contained therein configured to transfer the images to a remote sever or computer via the network for data processing. A final chlorophyll index value is calculated based on the transferred images.

A method includes: performing a time-frequency analysis on measurement data to obtain waveform data representing a temporal change in the intensity of each of a plurality of frequency components; dividing the waveform data of each of a plurality of predetermined frequencies into a plurality of segments so that each section where positive values successively occur and each section where negative values successively occur in a time-axis direction are defined as one segment; calculating the area of each of the segments to obtain segment values; creating, for the waveform data of each of the predetermined frequency components, a selected segment group by excluding a segment whose segment value exceeds a predetermined reference value from the segments in the waveform data; and determining a noise level of each of the predetermined frequency components based on the average value of the segment values of the segments included in the selected segment group.

A micro multi-array sensor includes a substrate, a sensor electrode formed on the substrate, and a heater electrode formed on the substrate. The sensor electrode includes a first sensor electrode formed on the substrate and a second sensor electrode formed on an opposite surface of the substrate from the first sensor electrode. The heater electrode is disposed more adjacent to the first sensor electrode than the second sensor electrode.

Vapor wake detection is a highly advantageous method and system for detecting explosives and other illicit substances. With vapor wake detection, a canine and a handler are used; however, unlike other detection schemes, the canine leads the handler. After the handler positions the canine in a desired location, the canine detects scents in the air that come to the canine. When the canine detects a trained scent, the canine leads the handler to or follows behind the carrier of the item with the scent. Once the carrier is identified by the handler, the proper personnel are contacted. To implement vapor wake detection effectively, specific rigorous training is utilized.

A thin film gas sensor device includes a substrate, a first pillar, a second pillar, a nanostructured thin film layer, and a first and a second electrical contact. The first and second pillars are supported by the substrate. The nanostructured thin film layer is formed with a semi-conductor material including holes. The semiconductor material is configured to undergo a reduction in a density of the holes in the presence of a target gas, thereby increasing an electrical resistance of the nanostructured thin film layer. The first and the second electrical contacts are operably connected to the nanostructured thin film layer, such that the increase in electrical resistance can be detected.

The present invention discloses a method and its variations for simultaneous detection of antibodies against two or more antigens of human immunodeficiency virus (HIV) and determination of approximate time (duration) post HIV infection, thereby confirming the infection, and determination of recency of an HIV infection. The number of individuals with recently infected HIV in a given period may be further used to estimate incidence of HIV in a population.