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  • Author or Editor: D. D. Mill x
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Summary  

Heat and CO2rates are measured on M. domesticapupae as a function of age and temperature. Heats of combustion of flies, pupae, and puparia are also measured. Heat and CO2rates decrease for 3 d post-pupation and increase exponentially over 4 d prior to eclosure. Heat and CO2rates are low and increase slowly from 5 to 23C, then rapidly increase from 23 to 26C, then more slowly up to 38C where pupae are stressed. Respiratory substrate varies with age and temperature, is a mix of lipids and carbohydrates, and has an average carbon oxidation state of -0.3 at room temperature. Humidity, elevated CO2, or reduced O2did not affect pupal metabolism.

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Abstract  

In this study we report on the comparison between the total selenium in serum (total Se) with that which is apparently bound to high molecular weight (>12,000 D) species, presumably proteins (bound Se). Nine hundred seventy seven (977) serum samples arising out of a population-based epidemiological study were prepared in duplicate for the determination of total Se by pipeting directly into irradiation vials; and separate duplicate aliquots were dialyzed against DI water for the determination of bound Se. All samples were analyzed by neutron activation analysis via77mSe (17.4 s). A small dialyzable Se component (6%) (free Se), defined as the difference between the total Se minus the bound Se, was identified.

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Abstract  

An instrumental neutron activation analysis (INAA) technique, based on the19F(n,)20F reaction, has been development for the determination of fluoride in bone. The purpose was to study fluoride distribution in different kinds of bone samples using a rabbit model. The rationale for the study stems from the posible correlation between fluoride in bone and osteoporosis. The sodium concentration in the bone was used to correct the20F peak area for the23F(n,)20F contribution. Two secondary standards, teflon tape and teflon coated dacron line, were used to quantify fluoride concentration. They proved to be stable and consistent with respect to their fluoride concentration. Bone specimens from 10 sites and two tooth samples were analyzed for fluoride. Fluoride concentration ranged from 305 ppm in the tibia long bone to 585 ppm in the humerus trochanter end and the magnitude of fluoride concentration levels is age depdentent. The detection limit of the fluoride is approximately 5 ppm using a 100 mg bone sample.

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