New article published in 12(4A) - ENAN / INAC 2024

Conservation of bibliographic collections using gamma ionization – paradigm for cultural collections professionals

Abstract: The preservation of cultural assets, especially bibliographic collections, requires the dissemination of the gamma ionization technique, which is mainly used for the decontamination and sterilization of these materials. The procedure, which is used to preserve library collections in Brazil and other countries, is also used to preserve documents and art collections, being safe to handle, after ionization, once it leaves no residue behind. The aim of the study was to assess knowledge and identify behavioral aspects related to gamma ionization and its application in decontaminating collections. The target audience was a group of professionals who work with cultural assets in Pernambuco and other states. Two questionnaires were used, obtaining 39 and 105 respondents respectively, characterizing the participants and their knowledge of gamma ionization. The research was qualitative and quantitative, of a phenomenological nature. For the analysis, questions were grouped into thematic blocks, characterizing the participants, finding out “knowledge of gamma ionization itself” – with both knowledge and ignorance of the concept and application of the technique – and also collecting from participants their feelings, opinions and positions on various aspects of the application of gamma ionization. Finally, means and personal sources of obtaining information were specified, dealing with sharing of information. Read full article

A dosimetric evaluation using the Monte Carlo method considering geometric variations of the Iodine-125 seed for brachytherapy

Abstract: The Institute for Energy and Nuclear Research – IPEN-CNEN/SP is uniquely positioned to develop a new source of Iodine-125 for brachytherapy treatment. Therefore, research into the dosimetric process and source design is widely studied. Task Group 43 – TG 43 cites methodologies for dosimetry of sources for brachytherapy, the most used method is Monte Carlo. However, the dosimetric protocol does not mention possible variations in the source geometry after its conception. The investigative focus of the work was to obtain measurements of the Iodine-125 seed during the production stages until completion, quantify them and simulate them using the Monte Carlo method with the MCNP – 4C code, the formalism was in water and a 101x101 matrix was used to calculate the dose point by point. Two variations were chosen: a) seed length; b) nucleus length, using a batch of 100 seeds for each case. 100 simulations were carried out for each variation and one simulation using the reference seed geometry. The following calculations were applied: relative difference to compare variations to the reference; average among the 100 seeds of each batch to calculate the standard deviation. In both cases there was no point that exceeded 4.48% relative difference, and for standard deviation the largest point was 1.6%, while the Type A uncertainty was 0.018% at the largest point. Read full article