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Abstract  

EAEN (Advanced School of Nuclear Energy, 2010) is an annual school that consists of a week of activities in the area of Nuclear Physics, Radiochemistry and uses of Nuclear Energy for a public made of high school students. The EAEN project represents a pioneering program on science education and dissemination of knowledge, conducted by researchers and focused mainly on high school and scientific education for the population in general. The school’s priority is to explore the failures and the lack of education in the dissemination of nuclear energy for high school students as well as to attract prospective students with great potential for graduate courses of IPEN and other institutions in Sao Paulo and in Brazil.

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In Brazil, dairy products are being enriched with folic acid (FA), an important vitamin for public health. With a view to guaranteeing a degree of confidence in these enriched products, the objective of this research was to determine the levels of FA in enriched dairy products such as powdered milk, sterilised milk, dairy beverages and ‘petit suisse’ cheese. The methodology used to determine FA by high performance liquid chromatography (HPLC) used a 0.1 mol 1 −1 KOH solution for extraction and trichloracetic acid for the clean up. A C 18 column was used for the separation with gradient elution using a mobile phase of acetate buffer and acetonitrile, which allowed for the completion of the analysis in 9 min. Detection was carried out at 290 nm and quantification by the way of an external standard. Of the twenty-five products analysed, sixteen presented FA values with only slight deviations from the values declared, whereas seven showed very low values, mainly sterilised milks and ready to drink dairy beverages, and in two of the three ‘petit suisse’ cheeses no vitamin was detected.

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Abstract  

Arsenic and cadmium contents in eight edible mushroom species (Agaricus bisporus, Agaricus sp, Pleurotus ostreatus, Pleorotus florida, Pleorotus eryngui, Pleurotus osteatus, Pleurotus salmoneostramineus, Lentinula edodes) consumed by Brazilian population were determined by instrumental neutron activation analysis (INAA) and graphite furnace atomic absorption spectrometry (GF AAS), respectively. Arsenic concentrations varied from 0.009 mg/kg in P. eryngui to 0.210 mg/kg dry weight in L. edodoes and Cd from 0.011 g/kg in P. eryngui to 0.229 mg/kg dw in P. salmoneostramineus. The consumption of mushrooms in São Paulo-Brazil may be considered safe from a toxicological point of view as As and Cd presented levels of ingestion are below the maximum levels recommended by the World Health Organization.

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Summary  

The crude methanolic extracts of a single bean from samples of organic, natural or genetically modified (GM) soybeans [Glycine max. (Merrill) L.] were analyzed by direct infusion electrospray ionization mass spectrometry (ESI-MS). These extracts, containing the most polar natural products of soybeans (free aglycones, monoglucosides, diglucosides and esters including isoflavones and flavones) provide characteristic fingerprinting mass spectra owing to different proportions or sets of components. Spectra distinctiveness is confirmed by chemometric multivariate analysis of the ESI-MS data, which place the three-types of beans into well-defined groups. When ESI-MS is applied, these polar components constitute therefore unique chemotaxonomic markers able to provide fast soybean typification.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Vasconcellos
,
P. Bode
,
G. Paletti
,
M. Catharino
,
A. Ammerlaan
,
M. Saiki
,
D. Fávaro
,
A. Byrne
,
R. Baruzzi
, and
D. Rodrigues

Abstract  

Biomonitoring of mercury contamination of Brazilian Indian population groups living in the Xingu Park, a reservation situated in the Amazonic region, has revealed very high levels of mercury in hair samples as compared to controls. Total mercury was determined by INAA in most of the tribes living in the Park and methylmercury was determined by CVAAS in samples with total mercury above 10 mg/kg. Due to the fact that selenium seems to protect animals against the toxic effects of methylmercury, it was considered also of interest to determine its concentrations in the hair samples with very high mercury levels. Selenium was determined by INAA via the short-lived radionuclide 77mSe (T 1/2 = 17.45 s). The correlations between selenium and mercury concentrations in Brazilian controls and in the Indian population groups are discussed.

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