Publications by authors named "Christopher Ballard"

Surveying active nuclear facilities for spread of alpha and beta contamination is currently performed by human operators. However, a skills gap of qualified workers is emerging and is set to worsen in the near future due to under recruitment, retirement and increased demand. This paper presents an autonomous ground vehicle that can survey nuclear facilities for alpha, beta and gamma radiation and generate radiation heatmaps.

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Equilibrium statistical mechanics allows the prediction of collective behaviors of large numbers of interacting objects from just a few system-wide properties; however, a similar theory does not exist for far-from-equilibrium systems exhibiting complex spatial and temporal behavior. We propose a method for predicting behaviors in a broad class of such systems and apply these ideas to an archetypal example, the spatiotemporal chaotic 1D complex Ginzburg-Landau equation in the defect chaos regime. Building on the ideas of Ruelle and of Cross and Hohenberg that a spatiotemporal chaotic system can be considered a collection of weakly interacting dynamical units of a characteristic size, the chaotic length scale, we identify underlying, mesoscale, chaotic units and effective interaction potentials between them.

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Aim: The study aims to investigate the prevalence of off-label prescribing in the general paediatric ward at a major teaching hospital in Tasmania, Australia.

Method: The drug charts and medical records from two groups of 150 consecutive paediatric patients, admitted 6 months apart in July 2009 and January 2010, were studied retrospectively. Patients were required to spend at least one night in hospital and be aged less than 12 years.

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Basal cell carcinomas (BCC) have a specialized microvasculature system that can be targeted by the 585-nm pulsed dye laser (PDL) utilizing the theory of selective photothermolysis. Seven volunteers with nine well-defined, biopsy-proven BCCs, were treated with the PDL (585-nm wavelength, a single 450-μs pulse, 7-mm spot size, and 9.0 J/cm(2) energy).

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Unlabelled: The aim of this study was to compare the effects of the pulsed-dye laser (PDL) at a wavelength of 585 nm with those at 595 nm in the treatment of post-surgical scars, starting on the day of suture removal. The study was a prospective, non-randomized, double-blind, controlled, clinical trial, set in an outpatient clinic. Fifteen outpatients with 21 post-operative scars at least 3 cm long were recruited, and 14 patients with 19 scars completed the study.

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A seed size-seed number trade-off exists because smaller seeds are produced in greater number but have a lower probability of establishment. This reduced establishment success of smaller-seeded species may be determined by biophysical constraints imposed by scaling rules. Root and shoot diameter, root growth extension rate (RGER) and shoot length at death for dark-grown seedlings are predicted to scale with the cube root of seed embryo and endosperm mass (m).

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A 42-year-old black woman presented with dermatosis papulosa nigra lesions of 15 years' duration. Coincident with the diagnosis of symptomatic iron-deficiency anemia about 1 year ago, she reported an "explosion" in number and size of the lesions progressing from her face to her trunk and arms. Physical examination revealed numerous 1-5-mm, black, smooth, verrucous papules predominantly on the forehead, malar region of the face, neck, and upper trunk (Figs 1 and 2).

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Propionibacterium acnes (P. acnes) and sebaceous glands are involved in the pathogenesis of acne. Although often effective, traditional therapies can have drawbacks, such as photosensitivity, other toxicities, polypharmacy and frequent dosing.

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Considered the most common skin disorder, acne affects millions of people every year. This multifactorial condition of the pilosebaceous follicle is a combination of at least four different primary pathogeneses. In recent years, acne therapies have been improving, becoming more effective, and targeting one or more of these causes.

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Background: A variety of uses have been described for cotton-tipped applicators.

Objective: We describe an additional application in surgeries involving the nose. This technique uses 8-inch obstetrics-gynecology applicators with oversized cotton tips, unlike most articles, which report the use of 6-inch applicators with smaller cotton heads.

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Basal cell carcinomas (BCCs) that arise in sun-protected sites are quite uncommon. We report a case of BCC of the areola, which is extremely rare. Mohs micrographic surgery was used for the treatment.

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