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rootworm contamination, of which the important advantages of the former modeling methods (visual calculation methods, sticky insect traps) are their low costs and their easy and quick application. These methods provide a relative estimate for population

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Abstract  

Hair samples were collected from 100 healthy people residing in Esfahan, Iran. The concentration of fourteen elements (Al, Br, Ca, Cl, Cu, Hg, I, K, Mg, Mn, Na, S, V, Zn) were determined by instrumental neutron activation analysis (INAA). The statistical results show that there are significant interrelations between some element such as: (Al-Mn, Al-V, Mg-Ca, Mn-V) and also there is no significant age correlation with any element. In addition, the results of this study are compared with the results obtained in England and New Zealand.

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Neutron activation analysis was applied to assess trace elements concentrations in head hair from healthy elderly people living in the São Paulo metropolitan area. Concentrations of As, Br, Ca, Cl, Co, Cr, Cu, Fe, K, La, Mn, Na, Sb, Se and, Zn were determined. Comparisons were made between the results obtained for dyed and non-dyed hair as well as for hair from females and males of two different age groups. The results were also compared with range values established by clinical laboratories and published data.

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In this preliminary study, scalp hair samples from 36 individuals resident in Sofia, Bulgaria, were analysed and Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, F, Fe, Hg, I, K, La, Mg, Mn, Mo, Na, Ni, Rb, S, Sb, Sc, Se, Sn, Sr, Ti, V, W, and Zn were determined. Instrumental neutron activation analysis (INAA) methods were used. Three washing procedures.: distilled-deionised water; acidacetone-water; and Triton X-100 detergent-water, showed a variable elemental change strongly dependent on the procedure used. More than 18 elements (Al, As, Ba, Ca, Ce, Cl, Co, Cs, F, Fe, I, K, La, Mo, Na, Ni, Sb, Sc, Sr and V) were easily removed by water-washing. Triton X-100 detergent was more effective in removing Ag, As, Au, Cl, Cs, K, Na and Rb; but not Hg. Only S and Zn were strongly incorporated in the hair structure (less than 10% being removable by any washing technique). There is no significant age correlation with any element between the various hair treatment groups. Elevated cadmium levels were found in the hair of smokers (0.711–4.913 g/g Cd) compared with nonsmokers (0.568–2.681 g/g Cd). Comparison of the elemental data for distilled water-washed hair and studies from Oxford, England and Hastings, and Hastings, New Zealand (using the same INAA method) revealed interesting variations dependent on local industrial and nutritional factors.

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Exposure to thorium can be estimated by measuring its quantity excreted daily in urine. For this purpose, an adequately sensitive analytical method was developed and standardized, employing radiochemical neutron activation analysis (RNAA). The method was applied to measure pg levels of Th in urine samples from which its daily urinary excretion was quantified. It was possible to achieve a limit of detection (LOD) of 10 pg Th (0.04 μBq) in urine samples. The daily urinary excretion of Th was measured in a group of 15 adult German subjects who were not occupationally exposed to Th. The daily urinary excretion ranged between 0.49-3.65 ng. d-1, with the geometric mean of 1.29 ng Th. d-1. This daily urinary excretion of Th provides an important baseline data against which the occupational exposure of workers could be assessed.

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In the 'normal' ageing brain a decrease in the cerebral metabolic rate has been determined across many brain regions. This study determines whether age differences would affect metabolic rates in regions and different hemispheres of the brain. The regional metabolic rate of glucose (rCMRGlu) was examined in a group of 72 subjects, ages 22 to 82 years, with 36 regions of interest chosen from both hemispheres of the cortex, midbrain and cerebellum. To determine metabolic rates the in-vivo technique of positron emission tomography (PET) was employed. Three age groups were chosen to compare hemispherical differences. In both young and intermediate age groups the left hemisphere had higher rCMRGlu values than those of the right for the majority of regions with, although less pronounced in the intermediate group. Importantly, the older age group displayed little difference between hemispheres.

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Energy-dispersive X-ray fluorescence analysis was applied for the analysis of hair. The hair samples were digested in a mixture of nitric and perchloric acid and the heavy metals were precipitated with ammonium pyrrolidine dithiocarbamate. The accuracy, precision and recovery of the method for the elements Fe, Ni, Cu, Zn and Pb were evaluated through the analysis of a standard hair sample. The procedure was applied to the analysis of hair from an occupationally exposed group of Sudanese workers and a control group. The hair of the exposed group showed a range of 80–550 ppm Fe, 6–12 ppm Cu, 57–190 ppm Zn and 70–3700 ppm Pb, while that of the control group had a range of 60–310 ppm Fe, 7–22 ppm Cu, 89–170 ppm Zn and 3–17 ppm Pb.

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Abstract  

The concentrations of eleven trace elements: Ca, Co, Cr, Cs, Fe, I,K, Se, Sr, Th and Zn were determined in total diet samples and also in individualfood materials which constitute the typical Indian diet. Instrumental neutronactivation analysis (INAA) and radiochemical neutron activation analysis (RNAA)were employed for the analysis. Whereas the elements Fe, Co, Cr, Se and Znare important from the view point of their role in nutrition, the elementsCs, K, Sr and Th are of importance in radiation protection, and Ca and I havedual importance: both in nutrition as well as in radiation protection. Basedon the analysis of twenty total diet samples, prepared as per the data onthe dietary intake pattern of four provinces of India and the data on intakepattern of an average adult Indian, the geometric mean (GM) intake of variouselements was estimated to be 0.33 g (0.2–0.67) for Ca, 16.5 µg(8.3–31.1) for Co, 52.3 µg (35.1–131) for Cr, 4.7 µg(2.79–11.8) for Cs, 94.6 µg (60.6–201) for I, 1.90 g (1.25–3.54)for K, 1.13 mg (0.78–2.97) for Sr, 0.76 µg (0.45–1.66) forTh, 15.9 mg (10.2–34.3) for Fe, 56.3 µg (27.6–105.3) forSe and 8.6 mg (5.1–16.7) for Zn. Some of the important individual foodmaterials, such as cereals, pulses, milk, vegetables etc., were also analysedfor these elements to observe the contributions of the individual food materialsto their daily dietary intake. The results of the analysis showed that inthe case of Cs, K, Sr, Th, Fe, Zn and Co, almost 50% of the daily dietaryintake of the above stated elements is contributed by cereals and pulses.In the case of Ca however, significant amount is contributed by milk and incase of I, iodised salt could make significant contribution. The data collectedso far, for Se and Cr, was not sufficient to draw any definite conclusion.

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