Infrared laser probe Ar/Ar geochronology, instrumental neutron activation analysis (INAA) and analytical electron microscopy have been performed on four 0.5 1.0 0.3 cm polished rock tiles of Apollo 16 and 17 granulitic breccias (60035, 77017, 78155, and 79215). Pyroxene thermometry indicates that these samples were re-equilibrated and underwent peak metamorphic sub-solidus recrystallization at ...

Measurements of partial-body calcium by in vivo neutron activation analysis have been carried out on normal and osteoporotic subjects. Based on measurements on 16 normal subjects (volunteers less than 55 years of age), a calcium index has been established that takes into account variation in skeletal frame size. On the basis of this index, all osteoporotic patients have bone mineral content les...

A triple stable-isotope method was used to estimate simultaneously selenium absorption from poultry meat intrinsically labelled with 74Se and from an extrinsic tracer of 76SeO3(2-) in four young adult men. The subjects received an experimental diet based on chicken meat as the source of protein. Two diet periods, lasting from 5 to 10 d, depending on the frequency of stool output for each subjec...

The assumption that the shape of the epithermal neutron spectrum can be described, in any research reactor, by the 1/E1+α function is a fundamental starting point of the k0 standardization. This assumption may be questioned from a reactor physics viewpoint. The type of moderator, the existence of neutron reflectors, the additional production of (γ, n) neutrons and resonance capture by construct...

Despite the role of iodine for proper development of the brain and the functions of the element, the accurate data on its concentration in brain tissue are largely lacking, the main reason being analytical difficulties associated with determination of the element especially at low levels. In this work, samples from human brain regions from Hungarian patients were analyzed using epithermal and r...

Scalp-hair samples from 40 multiple sclerosis patients and 42 controls were analyzed by neutron activation analysis, with a SLOWPOKE reactor as the neutron source. Ag, Al, As, Au, Ba, Br, Ca, Cl, Cu, l, K, Mg, Mn, Na, S, Sb, Se, Sr, V, and Zn were determined in samples of about 0.1 g. Highly significant differences (99% confidence) were observed between the two groups in concentrations of Cu, l...

Serum bromide has been used in the past to measure extracellular fluid volume in infants. In this report, a modification and refinement of a previously described spectrophotometric assay suitable for determining bromide levels in blood is presented. The assay involves sample deproteinization with perchloric acid followed by spectrophotometric analysis of the complexes formed by the reaction bet...

Previous cross-sectional studies using delayed gamma neutron activation analysis and whole body counting suggested that the relationship of total body calcium (TBCa) to total body potassium (TBK) (muscle mass, body cell mass) remained constant with age. This led to the hypothesis that the muscle mass and skeletal mass compartments are integrated in their response to aging. It had also been hypo...