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Volatile organic compounds (VOCs) are important precursors to the formation of ozone and fine particulate matter, the two pollutants of most concern in Sydney, Australia. Despite this importance, there are very few published measurements of ambient VOC concentrations in Australia. In this paper, we present mole fractions of several important VOCs measured during the campaign known as MUMBA (Measurements of Urban, Marine and Biogenic Air) in the Australian city of Wollongong (34°S). We particularly focus on measurements made during periods when clean marine air impacted the measurement site and on VOCs of biogenic origin. Typical unpolluted marine air mole fractions during austral summer 2012-2013 at latitude 34°S were established for CO2 (391.0 ± 0.6 ppm), CH4 (1760.1 ± 0.4 ppb), N2O (325.04 ± 0.08 ppb), CO (52.4 ± 1.7 ppb), O3 (20.5 ± 1.1 ppb), acetaldehyde (190 ± 40 ppt), acetone (260 ± 30 ppt), dimethyl sulphide (50 ± 10 ppt), benzene (20 ± 10 ppt), toluene (30 ± 20 ppt), C8H10 aromatics (23 ± 6 ppt) and C9H12 aromatics (36 ± 7 ppt). The MUMBA site was frequently influenced by VOCs of biogenic origin from a nearby strip of forested parkland to the east due to the dominant north-easterly afternoon sea breeze. VOCs from the more distant densely forested escarpment to the west also impacted the site, especially during two days of extreme heat and strong westerly winds. The relative amounts of different biogenic VOCs observed for these two biomes differed, with much larger increases of isoprene than of monoterpenes or methanol during the hot westerly winds from the escarpment than with cooler winds from the east. However, whether this was due to different vegetation types or was solely the result of the extreme temperatures is not entirely clear. We conclude that the clean marine air and biogenic signatures measured during the MUMBA campaign provide useful information about the typical abundance of several key VOCs and can be used to constrain chemical transport model simulations of the atmosphere in this poorly sampled region of the world. [ABSTRACT FROM AUTHOR]

An important task of mobility scholars is to attend to how time and space are generated through mobilities. Building upon research inspired by Deleuze and Guattari that foregrounds experiential mobilities, we use the notion of the refrain to chart experiences of long-distance rail commuting with a particular focus on how these journeys are crafted to be productive. Moreover, we consider a series of interruptions and their transformative potential. We read wanted and unwanted interruptions as breaks in the consistency of a refrain – disruptions to the socio-material, affective, and expressive arrangements that constitute a sense of productivity. We submit that in the wake of interruption, a refrain may dissolve or reform in three different ways: as repeat, as variation, or as developing variation. These categorisations help us to understand the differential influence of interruption on a refrain. We illustrate our argument by drawing on ethnographic research conducted with 16 mobile commuters who regularly journey by train for work between Wollongong and Sydney (Australia) – a trip of at least 90 minutes each way along a key commuting corridor. Through building an account of long-distance commuting, this article provides insights into how productivity (and productive subjects) may manifest through mundane activities. [ABSTRACT FROM AUTHOR]

Background: Cross-sectional studies suggest that more green space may lower the odds of prevalent diabetes, hypertension and cardiovascular diseases (CVD) in cities. We assess if these results are replicable for tree canopy exposure and then extend the study longitudinally to examine incident cardiometabolic outcomes.Methods: The study was set in the Australian cities of Sydney, Wollongong and Newcastle. Total green space and tree canopy as percentages of landcover within 1.6 km (1 mile) from home were linked to a residentially stable sample of 46 786 participants in the Sax Institute's 45 and Up Study (baseline 2006-09; follow-up 2012-15). Separate multilevel models were used to investigate whether the odds of prevalent and incident doctor-diagnosed diabetes, hypertension and CVD were associated with total green space and tree canopy provision, adjusting for age, sex, income, education, employment and couple status.Results: Lower odds of prevalent diabetes were observed with 1% increases in total green space [odds ratio (OR) 0.993, 95% confidence interval (CI) 0.988 to 0.998] and tree canopy (0.984, 0.978 to 0.989). Lower odds of prevalent CVD were found with a 1% increase in tree canopy only (0.996, 0.993 to 0.999). Lower odds of incident diabetes (0.988, 0.981 to 0.994), hypertension (0.993, 0.989 to 0.997) and CVD (0.993, 0.988 to 0.998) were associated with a 1% increase in tree canopy, but not total green space. At ≥30% compared with 0-9% tree canopy, there were lower odds of incident diabetes (0.687, 0.547 to 0.855), hypertension (0.828, 0.719 to 0.952) and CVD (0.782, 0.652 to 0.935). However, ≥30% compared with 0-4% total green space was associated with lower odds of prevalent diabetes only (0.695, 0.512 to 0.962).Conclusions: Restoring local tree canopy in neighbourhoods may help to prevent the incidence of cardiometabolic diseases. [ABSTRACT FROM AUTHOR]