EZEQUIEL DA SILVA
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Artigo IPEN-doc 27249 Evaluation of the performance of radioprotection ionization chambers used in radiometric survey of clinical systems2020 - SILVA, E.; SANTOS, L.R.; ASSEMANY, L.P.F.; POTIENS, M.P.A.The use of ionizing radiation for medical purposes was a major advancement for society due to the various possibilities of use for the treatment and diagnosis of diseases. On the other hand, knowledge about the damage caused by the biological effects of ionizing radiation requires a continuous improvement of the quality control of diagnostic radiology. Radiation detector equipment is used to measure the levels of radiation emitted by sources be they natural or artificial. For practicality and precision, among the most commonly used detectors are the ionization chambers. Especially in outdoor areas climatic factors may affect the behavior of these detectors at the time of measurement, but Brazilian legislation only recommends the calibration of these measuring instruments in a traceable laboratory every two years to ensure their reliability. The objective of this work was to evaluate the performance of an ionization chamber used in radioprotection measurements in diagnostic radiology equipment, considering the climatic variations in the different regions of Brazil. For this, a system was developed to simulate the environmental conditions found for the parameters of temperature and humidity at the time of clinical measurements, making it possible to estimate the influence of these factors on the values obtained.Artigo IPEN-doc 27208 Evaluation of 3D printing filaments for construction of a pediatric phantom for dosimetry in CBCT2020 - ASSEMANY, LADYJANE P.F.; RODRIGUES JUNIOR, ORLANDO; SILVA, EZEQUIEL da; POTIENS, MARIA da P.A.Cone-beam computed tomography (CBCT) has been widely used in orthodontics, due to the ability to provide visualization of mineralized tissues in high definition and consequently the identification and delimitation of three-dimensional irregularities. Compared with 2D imaging techniques, the doses used in CBCT exams are higher. Considering that the pediatric and adolescent population routinely receives orthodontic treatments, it is important to note that the cellular development phase of the organs is associated with increased tissue sensitivity to radiation, and that cancer is one of the main long-term effects caused by exposure to X radiation. In recent years, the 3D printing technique has been used in the medical industry because it allows the reproduction of structures of the human body, enabling detailed studies in several application areas. The objective of this work was to study the different types of filaments available for 3D printing of structures that will compose a phantom for dose evaluation in the pediatric and adolescent population who undergo CBCT exams.Artigo IPEN-doc 26747 Evaluation of the behavior of a 180cc ionization chamber under different environmental conditions2019 - SILVA, E.; SANTOS, L.R.; ASSEMANY, L.P.F.; POTIENS, M.P.A.The use of ionizing radiation for medical purposes has been a major advance for society due to the numerous possibilities of use for the treatment and diagnosis of diseases. On the other hand, knowledge about the damage caused by the biological effects of ionizing radiation requires continuous improvement of diagnostic radiology quality control. Radiation detector equipment is used to measure radiation levels emitted from natural or artificial sources. For convenience and accuracy, among the most widely used detectors are ionization chambers. Especially outdoors, weather factors can affect the behavior of these detectors at the time of measurement, but Brazilian law recommends only calibrating these measuring instruments in a traceable laboratory every two years to ensure their reliability. The objective of this work was to evaluate the performance of an ionization chamber used in radioprotection measurements in diagnostic radiology equipment, considering climatic variations in different regions of Brazil. For this, a system was developed to simulate the environmental conditions found for the temperature and humidity parameters at the moment of the clinical measurements, allowing to estimate the influence of these factors on the obtained values.Dissertação IPEN-doc 26411 Avaliação do desempenho de câmaras de ionização para radioproteção em condições ambientais variadas2019 - SILVA, EZEQUIEL daEsse trabalho apresenta uma proposta metodológica para verificar o desempenho das câmaras de ionização comerciais para radioproteção utilizadas no levantamento radiométrico em radiodiagnóstico nas cinco regiões brasileiras para os parâmetros de umidade e temperatura.Para isso, foi construído um sistema de climatização para simular as diversas condições ambientais as quais estes instrumentos de medição são expostos quando utilizados em campo.O presente trabalho teve como objetivo diminuir erros na medição em função do desempenho das câmaras de ionização, aumentando a segurança dos trabalhadores ocupacionalmente expostos, dos usuários, do público em geral e impactar na redução com custos estruturais tais como troca de visoresplumbíferos, revestimento adequado das paredes das salas de radiologia dentre outras ações de radioproteção.Foram simuladas as condições climáticas das cinco regiões do território nacional, todos os estados simulados apresentaram coeficientes de variação em relação as taxas de dose acumulada menores que 5%. O sistema de climatização desenvolvido de baixo custo apresentou boa eficiência nas faixas de umidade no intervalo de 40% a 100% e para simulações partindo da temperatura ambiente até 50 °C. O sistema de climatização pode ainda ser utilizado para tratar a umidade dos instrumentos de medição melhorando significativamente sua performance.Resumo IPEN-doc 26060 Evaluation of the performance of radioprotection ionization chambers used in radiometric survey of radiology clinical systems2019 - SILVA, E.; SANTOS, L.R.; ASSEMANY, L.P.F.; POTIENS, M.P.A.Resumo IPEN-doc 26010 Performance evaluation of a cilindrical ionization chamber used in radiation protection measurements of diagnostic radiology clinical systems2018 - SILVA, EZEQUIEL da; ASSEMANY, LADYJANE P.F.; POTIENS, MARIA da P.A.