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Volatile organic compound (VOC) emissions were measured from Chinese Hamster Ovary (CHO) cell and T cell bioreactor gas exhaust lines with the goal of non-invasively metabolically profiling the expansion process. Measurements of cellular 'breath' were made directly from the gas exhaust lines using polydimethylsiloxane (PDMS)-coated magnetic stir bars, which underwent subsequent thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) analysis. Baseline VOC profiles were observed from bioreactors filled with only liquid media. After inoculation, unique VOC profiles correlated to cell expansion over the course of 8 d. Partial least squares (PLS) regression models were built to predict cell culture density based on VOC profiles of CHO and T cells (R 2 = 0.671 and R 2 = 0.769, respectively, based on a validation data set). T cell runs resulted in 47 compounds relevant to expansion while CHO cell runs resulted in 45 compounds; the 20 most relevant compounds of each cell type were putatively identified. On the final experimental days, sorbent-covered stir bars were placed directly into cell-inoculated media and into media controls. Liquid-based measurements from spent media containing cells could be distinguished from media-only controls, indicating soluble VOCs excreted by the cells during expansion. A PLS-discriminate analysis (PLS-DA) was performed, and 96 compounds differed between T cell-inoculated media and media controls with 72 compounds for CHO cells; the 20 most relevant compounds of each cell line were putatively identified. This work demonstrates that the volatilome of cell cultures can be exploited by chemical detectors in bioreactor gas and liquid waste lines to non-invasively monitor cellular health and could possibly be used to optimize cell expansion conditions 'on-the-fly' with appropriate control loop systems. Although the basis for statistical models included compounds without certain identification, this work provides a foundation for future research of bioreactor emissions. Future studies must move towards identifying relevant compounds for understanding of underlying biochemistry.

Harold Innis (1930) famously described Canada as a country comprised of 'hewers of wood and drawers of water'. The staples approach that he advanced and which his followers subsequently further developed has become a reference point for continuing debate over the economic importance and consequences of natural resource development in Canada, a debate reignited by the long commodities boom of 2000-14. In this article we examine another, overlooked legacy of the staples approach, namely, the ways in which its emphasis on linkages has provided a frame of reference for opponents of natural resource projects. This is illustrated by examining some of the contemporary contestations of resource projects in northern British Columbia. These examples also show, however, that the staples approach provides only a partial frame of reference for contemporary contestations; more recent concerns such as Indigenous rights, procedural fairness, and environmental issues also play a significant role in oppositional politics to resource projects. Nevertheless, our discussion shows that Canada at 150 is still debating the role that natural resource development should play, and that the legacy of the staples approach continues to play a role in the debate. Keywords: staples, natural resource development, Canada, British Columbia, Indigenous rights, environment, Introduction The long commodities boom of the period 2000-14 refocused attention on natural resource development in Canada. Seen in the last decades of the twentieth century as symbols of 'old' [...]