Christie MacDonald

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There are many pairs of related western and eastern avian taxa in North America, and for many of these, little is known about their interactions in sympatry. One example is provided by MacGillivray’s warblers Oporornis tolmiei and mourning warblers Oporornis philadelphia. There have been occasional reports of range contact and hybridization between these(More)
Five experiments which attempted to evaluate the relationship between orientation and curvature selectivity in human vision are described. In the first two experiments, threshold elevation for curved gratings was measured after exposure to similar gratings, with the use of either an adaptation (experiment 1) or a masking (experiment 2) paradigm. In both(More)
A sensitive and selective method for the determination of domperidone in human breast milk and serum has been developed. The same method may be successfully applied to both matrices to a lower limit of quantitation of 0.5 ng/ml. Samples are processed by a liquid-liquid extraction, and analyzed by LC-ESI-MS in positive ion mode. There was no interference, on(More)
RATIONALE The ability to measure both (135) Cs and (137) Cs can provide an estimate of the age and source of Cs isotopes in an environmental sample. Accelerator mass spectrometry (AMS) consistently reports lower abundance sensitivities than other techniques and, with the addition of an on-line reaction cell, simpler isobaric suppression. Therefore, an AMS(More)
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