This paper reviews the range of sensors used in electronic nose (e-nose) systems to date. It outlines the operating principles and fabrication methods of each sensor type as well as the applications in which the different sensors have been utilised. It also outlines the advantages and disadvantages of each sensor for application in a cost-effective low-power handheld e-nose system.

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Elastomeric nanofibers composed of cross-linked poly(2-hydroxyethyl methacrylate) are synthesized via a reactive electrospinning process. In this process, the photoinduced polymerization and cross-linking of polymers take place simultaneously during the electrospinning process. The produced nanofibers are mostly within the diameter range of 100-500 nm in the dry state. When they are immersed in aqueous solution, the nanofibers exhibit remarkably large elastic properties characteristic of bulk hydrogel materials.

"In this paper, the authors briefly review the findings of an earlier study on the patterns of both regional and metropolitan redistribution of immigrant groups in Canada. Against this backdrop, a hierarchical model of migration for immigrant groups for the period 1981-86 is developed and estimated. The internal redistribution of immigrants through postarrival migration has continued to be focused on metropolitan areas in general and on Toronto, Vancouver, and Montreal in particular. The distribution of previous immigrants plays a significant role over and above that of economic circumstances both in retaining immigrants in a particular city and in attracting members of immigrant groups from other cities."

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Although population aging at the national level has received much attention, its geographical dimensions have not. Here we explore the demographic processes which underlie population aging at the provincial and metropolitan scale for the periods 1991-1996 and 1996-2001. A demographic accounting framework is proposed which differentiates between the effects of aging-in-place and net migration on population aging. We also examine the relationships between the various measures of aging and social and economic characteristics of metropolitan areas over the two periods. We demonstrate that the path of population aging is susceptible to social and economic context; in particular, the struggles of the British Columbian economy in the second half of the decade and the deteriorating economies of older resources based communities are associated with increases in population aging over and above the general aging taking place in Canadian society.