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Abstract  

Bone samples from iliac crest were obtained from apparently healthy female (n = 4) and male (n = 8) subjects with ages between 15–50. Cortical and trabecular parts were separated and soft tissues like fat, muscle and blood were removed. Calcium, Mg, Na, Cl, Fe, Zn, Br, Sr, and Cs were determined by instrumental neutron activation analysis and other techniques, and their relations were discussed. Fairly good agreement was obtained with literature data. These values may serve as reference values for subjects from a Turkish population.

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Abstract  

Ten macro and trace elements were determined in the hair of GuiZhou and XinHuang mercury mine workers and children living near the mine by INAA and AFS. Comparative studies demonstrated that concentrations of certain elements were greater than those corresponding to the nonexposed population. The hair mercury contents of normal adults and children were 1.1 and 1.37 g g–1, respectively. Workers and children living in the polluted area show a mercury level range of 3.52–317 and 1.50–34.7 g g–1, respectively.

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Abstract  

The objective of the present work is the estimation of the210Po content in some beverages and in tobacco, in order to assess the corresponding collective doses to the population in Argentina. Yerba mate, tea leaves, their infusions and ground coffee were analyzed, as well as tobacco. Collective doses due to the annual consumption of the beverages described were found to be from 6 man.Sv to 1200 man.Sv. Results for210Po in tobacco ranged from 10 Bq·kg–1 to 80 Bq·kg–1. Lung doses due to the use of tobacco vary from 75 Sv·y–1 to 600 Sv·y–1.

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Abstract  

In an attempt to characterize radon distribution in residential settings, the USEPA initiated two distinct survey programs, the National Residential Radon Survey (NRRS) and the State/EPA Residential Radon Survey (SRRS). Each survey is different in their level of analysis, with the NRRS concentrating on a national sample, and the SRRS concentrating on individual statewide samples. Both surveys are random and statistically-valid, enabling the survey samples to be extrapolated to represent a much larger population. This paper details each survey's design and provides an examination of the unique approach each program uses to generate sound characterizations of radon distribution in the United States.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Mason, J. Morris, V. Spate, C. Baskett, T. Nichols, T. Horsman, L. Le Marchand, L. Kolonel, and S. Yukimoto

Abstract  

The measurement of dietary selenium intake in a free-living population using dietary recall techniques has been shown to be spurious. Consequently, in our laboratory, we have focused on the development of biologic monitors such as blood, nails, hair and urine. In this paper, we report on the neutron activation analysis of whole blood, plasma and nail specimens collected from 285 Caucasian subjects, all permanent residents of Hawaii, participating in a malignant melanoma trial. Correlations between monitors are presented and discussed in the context of selenium determinants and integration of selenium intake.

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Gelatinisation temperatures as a function of moisture content were determined for potato starch. The native starch was then hydrothermally treated at a temperature 3% (Kelvin degrees) below the gelatinisation peak temperature and at moisture levels varying from 20 to 67% (by weight). Gelatinisation temperatures, temperature ranges and enthalpy values were affected for all treated samples. However, two sample populations could be distinguished: those samples treated under ‘limited’ moisture conditions and other samples treated in the presence of ‘extragranular’ moisture. A two-step hydrothermal treatment further increased the gelatinisation temperature, but the effect of the second step was small in comparison to that of the first.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Tran Thiep, Truong An, Nguyen Khai, Nguyen Vinh, Phan Cuong, I. Gangrski, I. Penhionzkevich, G. Mishinski, and V. Zemenhik

Abstract  

The ratio of the probabilities of population of the isomeric and ground states, so called the isomeric ratio is closely connected to the angular momentum of the initial fission fragments that is dissipated at the later stages of gamma ray cascade. This ratio also provides important information on the nuclear level structure as well as the nuclear reaction mechanism involved. In this work, the isomeric ratio in fission fragment 135Xe from photofission of 233U induced by 23.5 MeV bremsstrahlung has been determined by the method that uses inert gaseous flow. The results have been discussed and compared with that of other authors.

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Abstract  

This study aims to investigate whether known carcinogenic chemical elements in atmospheric deposition might be associated with child mortality due to leukemia in the Portuguese population. A Bayesian hierarchical model was used to explore the association between lichen biomonitoring measurements of four elements—As, Hg, Ni, Pb—and childhood leukemia death counts taken at small administrative units. This geographical epidemiological study found a non-significant positive association between the risk of childhood leukemia and levels of arsenic, mercury and lead, and a non-significant negative association between the disease and the level of nickel. Lead seems to show a weaker association with childhood leukemia than arsenic and mercury.

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Abstract  

Phosphoric acid is generally obtained from an aqueous process starting with the reaction between phosphate rock and sulphuric acid. Due to their chemical similarity, uranium is usually associated with phosphate rock which during chemical processing is partitioned to phosphoric acid. Uranium determination in this matrix is a very important task because of its ingestion it could lead to radiological impact on the population. Therefore, a procedure was developed using an initial precipitation with calcium hydroxide and evaporation, followed by instrumental neutron activation analysis (INAA). The procedure was applied to analyse fourteen uranium enriched phosphoric acid samples.

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Abstract  

The objective of this study was to evaluate the concentrations of essential and toxic elements in hair of children in Tanzania in order to assess their nutritional status. 141 samples of hair from boys and girls living in Tanzania were analyzed using instrumental neutron activation analysis (INAA). The mean concentration levels of Zn and Cu were lower whilst those of other elements were in the same range as the hair elemental concentrations reported in the literature. The lower concentrations of Zn might be related to the diet of mainly cereals with low animal proteins consumed by most of the Tanzanian population.

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