John A Dalziel

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In the past four years, four patients with progressive supranuclear palsy have presented to the Department of Geriatric Medicine, Oxford, under the care of one of us (RAG). They were all females whose symptoms began in the sixth or seventh decade. They died from three to six years after the onset of symptoms. All had neuropathological studies which are(More)
Dimethylnaphthalene (DMN) was shown to be an effective sprout suppressant. In the laboratory and in a commercial seed potato store, a DMN isomer mixture applied at 100 mg kg−1 controlled sprout growth as effectively as tecnazene applied at 135 mg kg−1. When seed tubers, treated at 100 mg kg−1, were aired for 4 to 7 weeks before planting, subsequent(More)
Most human exposure to mercury (Hg) in the United States is from consuming marine fish and shellfish. The Gulf of Maine is a complex marine ecosystem comprising twelve physioregions, including the Bay of Fundy, coastal shelf areas and deeper basins that contain highly productive fishing grounds. Here we review available data on spatial and temporal Hg(More)
Methylmercury (MeHg) bioaccumulation in marine food webs poses risks to fish-consuming populations and wildlife. Here we develop and test an estuarine mercury cycling model for a coastal embayment of the Bay of Fundy, Canada. Mass budget calculations reveal that MeHg fluxes into sediments from settling solids exceed losses from sediment-to-water diffusion(More)
Evasion from first- and second-order streams in a watershed may be a significant factor in the atmospheric recycling of volatile pollutants such as mercury; however, methods developed for the determination of Hg evasion rates from larger water bodies are not expected to provide satisfactory results in highly turbulent and morphologically complex first- and(More)
Tecnazene (1, 2, 4, 5-tetrachloro-3-nitrobenzene) treated potato tubers analysed by a gas chromatographic method were found to contain tecnazene residue levels ranging from 8.2 mg kg1 near the surface of the tubers to approximately 0.2 mg kg1 near the centre of the tubers. Residue levels in laboratory and commercially treated samples were examined at(More)
The sprout suppressant properties of 20 naturally produced volatile chemicals were assessed experimentally. The compounds tested were α-pinene, benzothiazole, 1,4-dimethylnaphthalene, 1,6-dimethylnaphthalene, 2,3-dimethylnaphthalene, citral, camphene, citronellol, coumarin, α-terpineol, naphthalene, limonene, 2-methoxy-3-ethylpyrazine, biphenyl, carvone,(More)
Produced water undergoes changes in its physical chemistry including precipitation of heavy metals after being discharged and mixed with ambient seawater. Potential impacts of the precipitation of heavy metals on their transport and toxicity were studied using samples from offshore oil production sites on the Scotian Shelf off eastern Canada. Concentrations(More)