Abstract: A method of transferring a digital item session state between at least two devices (A, B) using digital items, the method including: providing a content digital item to one of said devices (B); the one of said devices (B) configuring said content digital item according to predetermined requirements; transferring one or more context digital items representing the content digital item's session state from the other device (A) to the one device (B) and the one device (B) configuring said content digital item on the basis of the context digital item. A method of configuring a digital content item on the basis of a stored digital context item is also disclosed.

Abstract: A method of determining a trace gas concentration in a gas sample utilizing Fourier Transform Infrared Spectroscopy. The method includes the steps of(i) synthetically calibrating a spectrometer, and(ii) determining a spectral window within which to fit a calculated spectral trace to an experimental spectral trace by(a) choosing a series of candidate windows;(b) determining the likely error measure associated with a fitting of the spectral trace for each of the series of candidate windows;(c) utilizing the likely error measure associated with each of the fitting to determine a final window having substantially the lowest likely error measure; and(d) utilizing the final window as the spectral window.The calibration and the spectral window is then utilized to fit a calculated spectral trace to a spectral trace measured by the spectrometer and to determine the concentrations of constituent gases.