BackgroundParental influences are essential to the behaviours and physical activity of their children. Our study aimed to determine if parental beliefs and support are associated with children’s pedometer measured physical activity levels on school days and weekend days.MethodsIn the spring of 2009 and 2011, we analyzed cross-sectional data from 1,355 grade five students and parents in 30 schools in Alberta, Canada. Parents reported how much they care about exercising, how much they encourage their child to be physically active, and how frequently they engage in physical activities with their child. Physical activity was assessed from step counts obtained from time-stamped pedometers collected over nine consecutive days.ResultsIncreased parental encouragement was positively associated with boys’ and girls’ physical activity on school days (Boys: beta = 1373, 95% CI: 606, 2139; Girls: beta = 632, 95% CI: 108, 1155) and girls’ physical activity on weekend days (beta = 997, 95% CI: 130, 1864). Increased parental care was positively associated with boys’ physical activity on weekend days (beta = 1381, 95% CI: 85, 2676). Increased parental support and engagement was associated with an additional 632–1381 steps/day for children in this study.ConclusionsParental care, encouragement and engagement are associated with physical activity levels of children 10–11 years of age. Policy makers and researchers should consider the importance of targeting parents when designing strategies to promote physical activity in children. This is particularly relevant to weekends and holidays when children’s activity levels are low.

Monolayer epitaxial graphene (EG) has been shown to have clearly superior properties for the development of quantized Hall resistance (QHR) standards. One major difficulty with QHR devices based on EG is that their electrical properties drift slowly over time if the device is stored in air due to adsorption of atmospheric molecular dopants. The crucial parameter for device stability is the charge carrier density, which helps determine the magnetic flux density required for precise QHR measurements. This work presents one solution to this problem of instability in air by functionalizing the surface of EG devices with chromium tricarbonyl-Cr(CO) 3. Observations of carrier density stability in air over the course of one year are reported, as well as the ability to tune the carrier density by annealing the devices. For low temperature annealing, the presence of Cr(CO) 3 stabilizes the electrical properties and allows for the reversible tuning of the carrier density in millimeter-scale graphene devices close to the Dirac point. Precision measurements in the quantum Hall regime show no detrimental effect on the carrier mobility.

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