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We show that high-temperature reduction in a CO-CO(2) atmosphere increases the photorefractive sensitivity of KNbO(3):Rh at 860nm by 4 orders of magnitude compared with that of the as-grown crystal. The effective trap density is increased by a factor of 3, and the photoconductivity by a factor of 30, and the photorefractive response at a grating spacing of 0.15 mu;m is accelerated by a factor of 400. The grating buildup time at a grating spacing of 0.7 microm and an intensity of 1Wcm(-2) is 0.5 s, a value comparable with that of as-grown KNbO(3):Fe at visible wavelengths. The optical and photorefractive parameters of Rh-doped KNbO(3) subjected to reduction treatment are characterized for wavelengths of 0.48-1.064 microm .

The digestive tracts of one local, eight spring migrant, and 16 fall migrant bufflehead ducks (Bucephala albeola L.) collected at Delta, Manitoba, were examined for helminths. Twenty-five species (5 nematode, 8 trematode, 11 cestode, and 1 acanthocephalan) were found. Thirteen species occurred in both spring and fall migrants, four occurred in spring migrants only, and six were found only in fall migrants. The species composition of the helminth fauna of buffleheads resembles that of lesser scaup more closely than that of any other anatid species studied to date.

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