Abstract: A method for using saliva to measure at least one substance or physiological parameter of a human or animal subject may involve inserting a first end of a sensor into a handheld saliva testing device. The method may also involve receiving saliva from the subject on a second end of the sensor, moving the saliva from the second end of the sensor to the first end, and processing the saliva with the handheld saliva testing device to provide initial saliva data related to the at least one substance or physiological parameter of the subject. In some embodiments, the sensor remains inserted in the handheld device while the subject deposits saliva on the opposite, free end of the sensor.

Abstract: A device for indicating violation of a temperature limit of an item is provided. The device is positionable near the item and includes a sensor configured to change its state permanently when the temperature limit is violated. The change in sensor state is machine-readable to provide a permanent indication of the temperature limit violation. The sensor includes a reservoir for storing a fluid that changes phase from a solid to a liquid when the temperature limit is violated and a channel in fluid communication with the reservoir for receiving flow of the fluid in liquid phase from the reservoir. The sensor is arranged to allow flow of the fluid in the liquid phase such that the state of the sensor is permanently changed. The sensor is further configured to prevent the fluid flow from permanently changing the sensor state until activation of the sensor from a resting state. A system and method for detecting violation of a temperature limit of an item using the device is also provided.

Abstract: A device for indicating violation of a temperature limit of an item is provided. The device is positionable near the item and includes a sensor configured to change its state permanently when the temperature limit is violated. The change in sensor state is machine-readable to provide a permanent indication of the temperature limit violation. The sensor includes a reservoir for storing a fluid that changes phase from a solid to a liquid when the temperature limit is violated and a channel in fluid communication with the reservoir for receiving flow of the fluid in liquid phase from the reservoir. The sensor is arranged to allow flow of the fluid in the liquid phase such that the state of the sensor is permanently changed. The sensor is further configured to prevent the fluid flow from permanently changing the sensor state until activation of the sensor from a resting state. A system and method for detecting violation of a temperature limit of an item using the device is also provided.

Abstract: A method for using saliva to measure at least one substance or physiological parameter of a human or animal subject may involve inserting a first end of a sensor into a handheld saliva testing device. The method may also involve receiving saliva from the subject on a second end of the sensor, moving the saliva from the second end of the sensor to the first end, and processing the saliva with the handheld saliva testing device to provide initial saliva data related to the at least one substance or physiological parameter of the subject. In some embodiments, the sensor remains inserted in the handheld device while the subject deposits saliva on the opposite, free end of the sensor.