Justin J Chapman

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The Large Underground Xenon (LUX) experiment is a dual-phase xenon time-projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota). The LUX cryostat was filled for the first time in the underground laboratory in February 2013. We report results of the first WIMP search data set, taken during the period from April to(More)
OBJECTIVES To assess physical activity (PA) and sedentary behaviour (SB) in non-institutionalised adults with mental illness, using a combination of self-report and objective measures. DESIGN Cross-sectional METHODS Participants completed PA questionnaires (time spent walking for transport, walking for recreation, gardening, vigorous-, and(More)
The life expectancy of adults with mental illness is worse than that of the general population and is largely due to poor physical health status. Physical activity has been consistently recommended for the prevention and management of many chronic physical health conditions and can also have benefits for mental health. This cross sectional study assessed(More)
We present constraints on weakly interacting massive particles (WIMP)-nucleus scattering from the 2013 data of the Large Underground Xenon dark matter experiment, including 1.4×10^{4}  kg day of search exposure. This new analysis incorporates several advances: single-photon calibration at the scintillation wavelength, improved event-reconstruction(More)
BACKGROUND Adults with mental illness may have specific attitudes toward physical activity (PA). AIMS To assess the PA attitudes of non-institutionalised adults with mental illness, and associations with psychological distress. METHOD Participants completed questionnaires on activity preferences (type, context and sources of support), motivators,(More)
An automated, interferometrically referenced scanning knife-edge beam profiler with submicron resolution is demonstrated by directly measuring the focusing properties of three aspheric lenses with numerical aperture (NA) between 0.53 and 0.68, with spatial resolution of 0.02 microm. The results obtained for two of the three lenses tested were in agreement(More)
Observation of rotational curve of spiral galaxies shows that a large fraction (∼23%) of the mass density of the universe is unaccounted for. Such a significant percentage of missing dark matter suggests that the universe may consist of new types of elementary particles. A compelling explanation for the new particles is the existence of Weakly Interacting(More)
BACKGROUND Adults with mental illness may have difficulties with data collection methods such as questionnaires and accelerometry. AIMS To assess the utility of questionnaires and accelerometry for assessing physical activity (PA) and sedentary behaviour (SB) in non-institutionalised adults with mental illness. METHODS Participants were recruited from(More)
OBJECTIVES The aim of this study was to assess levels and patterns of physical activity and sedentary behaviour among inpatient adults with mental illness. DESIGN Cross-sectional. METHODS 101 participants completed questionnaires on time spent in walking, moderate- and vigorous-intensity activity in the past week and domain specific sitting time on a(More)