Made available in DSpace on 2014-10-09T12:43:47Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:44Z (GMT). No. of bitstreams: 1 06775.pdf: 15025996 bytes, checksum: fbd53da186ea56301e555ed353c39360 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Submitted by Maria Eneide de Souza Araujo (mearaujo@ipen.br) on 2015-09-02T13:51:32Z No. of bitstreams: 0 / Made available in DSpace on 2015-09-02T13:51:32Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:53:16Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:40Z (GMT). No. of bitstreams: 0 / O valor alfa é um critério extremamente importante, pois determina o tempo que um País levará para atingir suas metas na diminuição da distribuição das doses em trabalhadores envolvidos com fontes de radiação ionizante. Atualmente os paises adotam um valor único para ? baseado no Produto Interno Bruto per Capita. Neste trabalho, pretende-se mostrar que seria possível a escolha de uma curva para ? ao invés de um único valor. Esta curva por sua vez, seria capaz de fornecer valores para ? que estariam vinculados às maiores doses individuais observadas em cada processo de otimização, tanto de projeto quanto de operação. Os valores para a construção das curvas ?, aqui sugeridos, não dependeriam mais do Produto Interno Bruto per Capita mas seriam função da distribuição das doses individuais máximas e do prazo necessário para atingir a meta de 1/10 do limite de dose anual previsto, isto é, alcançar a região de doses individuais consideradas aceitáveis. Esta nova conceituação do valor alfa viria resolver muitos problemas criados pela teoria atual, entre os quais destacamos: a) somente pode ser realizada uma otimização para cada conjunto (família) de opções de radioproteção. b) cada país tem limites restritos diferenciados, que podem causar graves problemas nos intercâmbios internacionais. c) dificulta o cálculo de prováveis casos de morte em virtude do valor da dose coletiva, considerado indesejável pelos organismos internacionais. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:34:31Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:57Z (GMT). No. of bitstreams: 0 / O fosfogesso é um resíduo da indústria de fertilizantes fosfatados que concentra radionuclídeos naturais. Neste trabalho foi estudada a taxa de exalação de 222Rn em placas e tijolos de fosfogesso, visando sua utilização na construção de residências. Para tanto, foram determinadas a taxa de exalação de 222Rn por meio da técnica da câmara de acumulação com detectores sólidos de traços nucleares (SSNTD) inseridos em uma câmara de difusão e a dose efetiva para um indivíduo habitando uma residência construída com esses materiais. A título de comparação foi também determinada a taxa de exalação teórica, por meio do modelo proposto pela UNSCEAR, a partir da concentração de 226Ra nas placas e tijolos de fosfogesso. A contribuição do revestimento na superfície dos materiais para a diminuição da taxa de exalação de radônio foi também avaliada. Foram estudados placas e tijolos fabricados com fosfogesso das empresas Bunge Fertilizantes, Ultrafertil e Fosfertil e tijolos fabricados com gesso comum. Os valores médios obtidos foram 0,19 0,06 Bq m-2 h-1, 1,3 0,3 Bq m-2 h-1 e 0,41 0,07 Bq m-2 h-1 para as placas fabricadas com fosfogesso proveniente das empresas Bunge, Ultrafertil e Fosfertil, respectivamente. Já para os tijolos de fosfogesso, os valores foram 0,11 0,01 Bq m-2 h-1, 1,2 0,6 Bq m-2 h-1, 0,47 0,15 Bq m-2 h-1, para o fosfogesso da Bunge, Ultrafertil e Fosfertil. O tijolo fabricado com gesso comum apresentou valor médio de 0,18 0,08 Bq m-2 h-1. As doses efetivas anuais para um indivíduo habitando uma residência construída como os tijolos ou placas de fosfogesso de qualquer uma das procedências ficaram abaixo do limite de dose efetiva para indivíduos do público de 1 mSva-1 estabelecido pela Comissão Internacional de Proteção Radiológica. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Made available in DSpace on 2014-10-09T12:43:47Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:44Z (GMT). No. of bitstreams: 1 06775.pdf: 15025996 bytes, checksum: fbd53da186ea56301e555ed353c39360 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Submitted by Maria Eneide de Souza Araujo (mearaujo@ipen.br) on 2015-09-02T13:51:32Z No. of bitstreams: 0 / Made available in DSpace on 2015-09-02T13:51:32Z (GMT). No. of bitstreams: 0 / Flores comestíveis são cada vez mais utilizadas nas preparações culinárias, sendo também reconhecidas por seus potenciais efeitos benéficos na saúde humana, o que exige novas abordagens para melhorar a sua conservação e segurança. Estes produtos altamente perecíveis devem ser cultivados sem o uso de agrotóxicos. Tratamento de irradiação pode ser a resposta a estes problemas, garantindo a qualidade dos alimentos, aumentando seu prazo de validade e desinfestação. Tropaeolum majus L. (capuchinha) e Viola tricolor L. (amorperfeito) são flores amplamente utilizadas nas preparações culinárias, sendo também reconhecidas por suas propriedades antioxidantes e alto teor de compostos fenólicos. O objetivo deste estudo foi avaliar os efeitos dose-resposta da irradiação por gama e feixe de elétron (doses de 0, 0,5, 0,8 e 1 kGy) sobre a atividade antioxidante, compostos fenólicos, aspectos físicos e potencial antiproliferativo das flores comestíveis. O flavonoide Kaempferol-O-hexosídeo-Ohexosídeo foi o composto mais abundante em todas as amostras de flores de Tropaeolum majus, enquanto Pelargonidina-3-O-soporosídeo foi a principal antocianina. Em geral, as amostras irradiadas demonstraram maior atividade antioxidante. Nas amostras da Viola tricolor, os compostos fenólicos mais abundantes foram os flavonois, especialmente aqueles derivados da quercetina. Em geral, as amostras irradiadas com raios gama, independentemente da dose aplicada, apresentaram quantidades mais elevadas m compostos fenólicos, os quais também foram favorecidos pela dose de 1,0 kGy independente da fonte utilizada. A atividade antioxidante também foi maior entre as amostras irradiadas. As duas espécies de flores comestíveis não apresentaram as amostras não apresentaram potencial antiproliferativo e citotoxicidade. Assim, os tratamentos por irradiação aplicados, demonstraram ser uma tecnologia viável para preservar a qualidade de pétalas de flores comestíveis, considerando as exigências impostas para sua utilização. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Introduction Radiologic Technologists exposed to continuous low dose radiation may have an increased risk for spontaneous abortions. Although the federally mandated radiation dose limit to the developing fetus of an occupational worker is 5mSv, well below the documented threshold of 100mSv, some studies have suggested an increased risk for spontaneous abortions in occupationally exposed females. The effects of exposure to low levels of radiation are difficult to discern from the usual occurrence and are limited in the literature because of the large sample size needed to achieve statistical power. This study contains data from 152,439 self-reported pregnancies and possesses the appropriate sample size to assess the risk of spontaneous abortions incident to radiologic technologists who maintain fetal radiation dose levels within federal guidelines. Methods This non-experimental retrospective designed study uses data from the United States Radiologic Technologist Study (USRTS). The USRTS began in 1982 as a joint effort between the American Registry of Radiologic Technologists (ARRT),UniversityofMinnesotaand the National Cancer Institute to study the radiation effects from low-dose occupational exposure. This longitudinal study follows more than 90,000 current and former technologists through periodic surveys and contains a sufficient sample size to overcome statistical power concerns. The provided data included the order and outcome of each self-reported pregnancy as well as the year of each live birth. The data were therefore manipulated to provide a likely gestational interval for both a reported live birth and spontaneous abortion. After calculating the spontaneous abortion rate for the final sample, a binary logistic regression was performed to determine if levels of estimated fetal radiation dose are associated with predicting the odds of a reported spontaneous abortion. A linear regression analysis was then performed to assess the relationship between the calculated odds ratios of a reported spontaneous abortion as a function of estimated fetal radiation dose, specifically to determine the significance of the linear relationship Results The overall spontaneous abortion incidence to the cohort reporting at least one live birth or spontaneous abortion was 14.8%, lower than the reported national incidence of 15-20%. Using up to 1mSv as the reference fetal radiation dose category, the odds ratios of a spontaneous abortion for 1-2mSv, 2-3mSv, 3-4mSv and 4-5mSv were calculated as 1.57, 1.82, 2.11 and 2.15 respectively. This increase in odds was linear with estimated fetal radiation dose as demonstrated by the significant regression equation (F=29.93, p = .01) and an R2 of 0.9089. Conclusions By demonstrating an increased risk at levels of radiation as low as natural background, and further demonstrating the risk increases linearly with radiation dose, the Linear Non-Threshold Theory appears to be the more likely risk model for predicting spontaneous abortions in lieu of the belief that a 100mSv threshold must first be exceeded for a radiation induced spontaneous abortion to occur. Application of this model demonstrates the risk of a spontaneous abortion is twice as likely in occupational workers whose fetal radiation doses are closer to the maximum allowable limit of 5mSv compared with those who maintain fetal radiation doses below 1mSv.

In 1959, approximately 20 km to the north-west of České Budějovice a construction of a chemical uranium ore plant MAPE began. The plant operation started in 1962 and finished in 1991. The premises of the former chemical plant MAPE Mydlovary consisted of a plant in which uranium ore was manufactured and the manufactured material from uranium mines was stored in adjacent sludge lagoons. Uranium ore has never been mined in this area, neither in its surroundings. It has always been imported from uranium mines. Uranium was made from the ores by either acid or alkali leaching. Although this former uranium ore plant MAPE Mydlovary hasn´t been economically active anymore, it is nowadays one of the biggest environmental burden which results from ore mining and it's processing in the Czech Republic. Therefore, it is important to carry out remediation and recultivation works which are currently provided by the state enterprise DIAMO. DIAMO company, in fact, is also the owner of the former plant MAPE Mydlovary. During the operation of the former ore plant MAPE Mydlovary, about 1,100 employees took turns in the company. During the uranium ore treating and its consequent waste store in the lunge lagoons, employees of the plant were exposed to the effect of radionuclides. For this reason, my diploma thesis deals with the effect of radiation on employees of the former chemical plant MAPE Mydlovary and aims at the doses which the employees received while working in the plant. The data were gathered from October 2013 to April 2014 and contain figures for a period of 1963-1996. These figures were gained from personal dosimetrical files of the employees and these files were provided by the state enterprise DIAMO. The first aim of the thesis was to monitor the rate of radiation and to compare the gained values among individual employees of the plant MAPE Mydlovary. The monitoring of the effect of radiation was carried out from personal files of the employees and the measured values were put into tables of Excel programme. The values were then compared and I also used descriptive figures statistics. The doses at the employees were found not to exceed any dose limits. The second aim of the thesis was to evaluate the measured values at several groups of employees according to the type of the work they do. The division into individual groups was carried out according to the scale of received doses. It deals with a group of employees who worked at least for 6 months with dustiness, another group working in a sludge lagoon, another group of workers who were responsible for the main manufacture but weren´t exposed to any dustiness (according to the type of work, these people were then divided either into the first or the second sub-group) and also a group of other employees who had their own dosimeter- this group served as a comparative reference in a statistic research. The measures values were evaluated by a statistic research. For this type of research, we used a parametric testing and a so-called Fischer´s F-test, which was applied thanks the Statistics function in a table processor MS Excel 2010. For this test, we used the level of significance = 0,05. Through the statistic research, we have found out that the highest measured values appeared at the employees who were working in the main manufacture but without any dustiness. This group of people was ranked as the first group. The lowest amount of received doses appeared at the employees who worked in the main manufacture, without any dustiness and were put into the second sub-group. The hypothesis that the doses of the MAPE Mydlovary employees are different within the groups has been confirmed. The hypothesis that the doses at the MAPE Mydlovary staff didn´t exceed any dose limits for the staff has been confirmed as well. The hypothesis that the doses at the MAPE Mydlovary staff were different in certain groups was confirmed.