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The role of exogenous thyroid hormone on visual pigment content of rod and cone photoreceptors was investigated in coho salmon (Oncorhynchus kisutch). Coho vary the ratio of vitamin A1- and A2-based visual pigments in their eyes. This variability potentially alters spectral sensitivity and thermal stability of the visual pigments. We tested whether the(More)
A field study was carried out to study the effect of firing the British L118/9 195 mm howitzer (Hamel gun) on the hearing of crewmen wearing EAR earplugs. Two guns and gun crews were placed 7 m apart, each gun firing 40 rounds during each of 2 successive days. Bekesy type audiometry was carried out before and after firing and was also used to measure the(More)
Quartz deformation lamellae parallel to c{OOO1} and planar features parallel to omega{10ī3} appear to be both characteristic of and reliable criteria for quartz deformed by shock due to impact by meteorite or comet. These features are readily distinguished from microstructures, induced during tectonic deformation, by differences in optical properties or(More)
Plagioclase and olivine crystals in the crystalline rocks from the Sea of Tranquillity show little or no evidence of either static or dynamic deformation. The large disorientations in many of the pyroxene crystals are commonly consistent with slip on the system T -(100), t = [001], but these distortions are not due to plastic flow. They are ascribed to(More)
The activation volume for creep, V*, of olivine-rich rocks has been determined in pressure-differential creep experiments on dunite at temperatures from 1100 degrees to 1350 degrees C and confining pressures from 5 to 15 kilobars. Values of V* range from 10.6 to 15.4 cubic centimeters per mole with a mean value of 13.4 cubic centimeters per mole, near that(More)
The Real Ear Attenuation at Threshold (REAT) of E-A-R (slow recovery) from earplugs was determined, using three methods of presentation of the test tones during a single fitting of the earplug. The three presentation methods were (a) sound-field listening; (b) TDH49 earphone mounted in the shell of a circumaural earmuff; and (c) TDH49 earphone in a Model 51(More)
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