Brazilian Journal of Radiation Sciences最新文献_第10页

Dose sensitivity of MAGIC-f polymer gel using different MRI sequences 不同MRI序列对MAGIC-f聚合物凝胶剂量敏感性的影响

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-20 DOI: 10.15392/2319-0612.2022.2085

N. G. Cavedini, R. Papaléo, Nícolas Borges Jobim, P. N. Schuck, Fabrício Nery Garrafiel, E. Oliveira, M. Schwarcke, A. C. H. Oliveira, P. Caribé, A. M. Marques da Silva

{"title":"Dose sensitivity of MAGIC-f polymer gel using different MRI sequences","authors":"N. G. Cavedini, R. Papaléo, Nícolas Borges Jobim, P. N. Schuck, Fabrício Nery Garrafiel, E. Oliveira, M. Schwarcke, A. C. H. Oliveira, P. Caribé, A. M. Marques da Silva","doi":"10.15392/2319-0612.2022.2085","DOIUrl":"https://doi.org/10.15392/2319-0612.2022.2085","url":null,"abstract":"This study aims to evaluate the dose sensitivity of MAGIC-f gel irradiated by high-energy photon beams, comparing quantification using different MRI sequences. Irradiation was performed using 6 MV photons with 600 cGy/min dose rate, field size of 20x20 cm², and 94 cm source-to-surface distance. Two gel batches were produced on different days and placed in vials. In the first batch, doses of 0, 2, 4, 6, 8, 10, 20, and 40 Gy were planned. The second batch was irradiated with doses of 0, 2, 4, 6, 10, 12, 14, and 16 Gy. MR images were acquired with Spin Echo (SE, TR=3 s) and Multi Spin Echo (MSE, TR = 3s or 10s, turbo factor 24) sequences. The dose is assessed via changes in the transverse relaxation time in the irradiated gel. In MSE, dose sensitivity in the first batch was 0.27 (TR=3 s) and 0.28 Gy-1s-1 (TR=10 s) and in the second batch, 0.31 and 0.31 Gy-1s-1 (TR = 3 s and TR = 10 s, respectively). In the SE sequence, dose sensitivity was 0.42 for the first batch and 0.43 Gy-1s-1 for the second batch. Linearity of dose-response was only obtained for doses below 10 Gy. Comparing the dose sensitivity extracted from MSE and SE sequences using TR= 3s, differences around 30% were found. Thus, although MSE-MRI offers a faster protocol of imaging acquisition it is less precise for quantification of relaxation times, as TE is not a well-defined quantity. The performance of the gel as a dosimeter is consequently sequence dependent.","PeriodicalId":9203,"journal":{"name":"Brazilian Journal of Radiation Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74492303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Uncertainty evaluation in activity measurements with HPGe using two relative methods 用两种相对方法评价HPGe活度测量中的不确定度

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-20 DOI: 10.15392/2319-0612.2022.2070

M. C. M. De Almeida, J. U. Delgado, R. L. Silva, R. Poledna, R. S. Gomes, A. L. Ferreira Filho

引用次数: 0

Proposal of Brazilian National Program for Quality Control in the small animal PET scanners 巴西国家小动物PET扫描仪质量控制方案提案

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-04 DOI: 10.15392/2319-0612.2022.1978

R. Gontijo

{"title":"Proposal of Brazilian National Program for Quality Control in the small animal PET scanners","authors":"R. Gontijo","doi":"10.15392/2319-0612.2022.1978","DOIUrl":"https://doi.org/10.15392/2319-0612.2022.1978","url":null,"abstract":"In Brazil, currently there are six preclinical molecular imaging centers and seven different small animal PET systems in use. However, there is still no national specific legislation for research laboratories focused on preclinical molecular images, unlike clinical nuclear medicine centers. A standardization of quality control protocols is needed to harmonize the use of small animal PET scanners in the research field. Thus, the aim of this work was to propose a National Program for Quality Control (NPQC) for the preclinical PET imaging systems in Brazil. This work was based on the quality control tests performed in Molecular Image Laboratory LIM/CDTN based on NEMA NU 4-2008 as described and presented in doctoral thesis of GONTIJO, 2019. The proposal of the NQCP was based on the CNEN NN 3.05 Publication (2013) and includes fundamental tests to be adopted, if possible, in laboratory practice to corroborate the experimental data. The Quality Control Program implemented in LIM/CDTN is an innovative and unprecedented proposal in the scope of preclinical molecular imaging services in Brazil. Therefore, the LIM/CDTN Program was carried out as a pilot to evidence the applicability and viability of the NQCP using small animal PET scanners. Summarizing, this work presents a viable set of Quality Control tests and their periodicities like a proposal for standardization to harmonize the use of this imaging technology in the field of research. Therefore, a National Quality Control Program (NQCP) applied to small animal PET scanners.","PeriodicalId":9203,"journal":{"name":"Brazilian Journal of Radiation Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77694532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Semiconductors (LEDs) quality control based in high-resolution 3D X-ray microscope 基于高分辨率三维x射线显微镜的半导体(led)质量控制

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-04 DOI: 10.15392/2319-0612.2022.1955

Diogo Da Costa, M. D. dos Anjos, D. Oliveira, Alessandra Machado, Joaquim Teixeira de Assis, Ricardo Lopes

{"title":"Semiconductors (LEDs) quality control based in high-resolution 3D X-ray microscope","authors":"Diogo Da Costa, M. D. dos Anjos, D. Oliveira, Alessandra Machado, Joaquim Teixeira de Assis, Ricardo Lopes","doi":"10.15392/2319-0612.2022.1955","DOIUrl":"https://doi.org/10.15392/2319-0612.2022.1955","url":null,"abstract":"Electronic devices are getting smaller each time and the technology, increasingly complex. Commonly found problems such as reflow soldering and open solder connections, which are mostly difficult to detect by conventional means like X-ray images or physical cut on the transverse section. Along with the challenge of finding these flaws, there are also some problems that may arise on the exposure of them using destructive analysis techniques, such as the fiscal transversal cut and chemical decapsulation. Both techniques may induce damage not relevant to where that flaw is located or remove evidence of a flaw or a damaged place. The high-resolution 3D x-ray computerized microtomography provides a powerful alternative solution and non-invasive to issues that involve the analysis of semiconductor devices. This research contemplates the study of semiconductor’s integrity (LED’s) based of X-ray computerized microtomography. The SkyScan 1272 Bruker commercial equipment was used for analysis of the P-N junction in a set with 10 LEDs, under non polarized conditions and upon electrical overstress effects on its contact terminals. The P-N junction had their dimensions analyzed on the three spatial directions (x, y and z) and studied on the effects that occur when a LED is damaged. The study methodology of integrity regarding computerized microtomography have shown consist outcomes that allowed the understanding of what occurs on the LED's structure and investigates matters that allows decisions to be made regarding its quality, and so, accomplishing the goals designated on this research.","PeriodicalId":9203,"journal":{"name":"Brazilian Journal of Radiation Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80416703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Precautionary and preventive measures in Brazilian law applied to radioactive waste management 巴西法律中的预防和预防措施适用于放射性废物管理

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-04 DOI: 10.15392/2319-0612.2022.1899

Monise Andrade

{"title":"Precautionary and preventive measures in Brazilian law applied to radioactive waste management","authors":"Monise Andrade","doi":"10.15392/2319-0612.2022.1899","DOIUrl":"https://doi.org/10.15392/2319-0612.2022.1899","url":null,"abstract":"Nuclear technologies and radiation have offered technological and scientific growth nowadays, but there is a frequent paradox in this. While these technologies substantially increase the quality of human life, they also produce radioactive waste, which, when not properly managed, can generate risks that threaten to harm the environment and health. As a result, in risk management of radioactive waste, decision-making processes need to be guided by a framework of principles, including the precautionary and preventive principles. For this reason, the present work proposes to develop a legal analysis on radioactive waste risk management using the principles of precaution and prevention. These principles have similarities, but it is the differences in their structure that deserve to be highlighted, which is discussed and exemplified throughout this work. Furthermore, national and international experience in environmental damage has taught us that an identification and assessment of risk is necessary, because if preventive measures are not taken radioactive waste can be dispersed and harm the environment. When it comes to assessing the risk of radioactive waste, one of the precautionary measures is the application of a conservative stance in modelling scenarios, as there are still uncertain risks. Therefore, comprehending the different circumstances surrounding precautionary and preventive measures and having effective information about risk is essential for successful risk management.","PeriodicalId":9203,"journal":{"name":"Brazilian Journal of Radiation Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85330218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of 18F-FDG and 68-PSMA-11 in PET for prostate cancer diagnosis 18F-FDG与68-PSMA-11在PET诊断前列腺癌中的比较

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-04 DOI: 10.15392/2319-0612.2022.2007

Natalia Fulle, G. Sabundjian

{"title":"Comparison of 18F-FDG and 68-PSMA-11 in PET for prostate cancer diagnosis","authors":"Natalia Fulle, G. Sabundjian","doi":"10.15392/2319-0612.2022.2007","DOIUrl":"https://doi.org/10.15392/2319-0612.2022.2007","url":null,"abstract":"Prostate cancer is the second most incident neoplasm in men, except for non-melanoma skin cancer, and has the second highest mortality rate in Brazil. Early diagnosis increases the chances of cure and enables a less aggressive treatment for the patient. Nuclear Medicine presents effective alternatives for prostate cancer diagnosis, such as Positron Emission Tomography (PET) or PET and Computed Tomography (PET/CT) imaging. The aim of this study is to compare the advantages and disadvantages of the radiopharmaceuticals 18F-FDG and 68Ga-PSMA-11 used for PET or PET/CT in the diagnosis of this type of cancer. Compared to 18F-FDG, 68Ga-PSMA-11 has some advantages such as its availability by means of generators, the independent production of a cyclotron facility and its theranostic potential. The disadvantages compared to 18F-FDG are the scalability of 18F-FDG production compared to limited generator production. Despite its favorable characteristics, the radiopharmaceutical 18F-FDG has limitations in the diagnosis of some types of tumors, such as prostate cancer. All the favorable and unfavorable aspects of these two radiopharmaceuticals are presented in this work.","PeriodicalId":9203,"journal":{"name":"Brazilian Journal of Radiation Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89500183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of pore geometry in the compacted fine aggregate matrix by x-ray microtomography 用x射线微层析技术分析致密细聚集体基质中的孔隙几何结构

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-04 DOI: 10.15392/2319-0612.2022.1862

Rogério F. Costa

{"title":"Analysis of pore geometry in the compacted fine aggregate matrix by x-ray microtomography","authors":"Rogério F. Costa","doi":"10.15392/2319-0612.2022.1862","DOIUrl":"https://doi.org/10.15392/2319-0612.2022.1862","url":null,"abstract":"This study employs the advanced X-ray microtomography technique to evaluate the open and closed porosity geometry within fine aggregate matrix specimens extracted from different locations of SGC samples compacted with distinct densities. The adoption of advanced techniques such as the X-ray microtomography facilitate the fabrication of FAMs that are more representative of those that comprise asphalt concretes, as well as allow the use of similar replicates in mechanical tests. In addition, the traditional porosity assessment methods are well documented, but provide only global average results for the entire sample. In this context, X-ray microtomography stands out because, besides porosity information, pore distribution and a series of other parameters related to the internal structure of the object can be evaluated. This study evaluated the geometry of open and closed pores of FAM specimens extracted from different locations of SGC compacted samples. From the results and analyses, it can be concluded that the shape of the closed pores is spherical and the shape of the open pores is cylindrical for the SGC samples compressed with 2.26 g/cm3, 2.34 g/cm3 and 2.44 g/cm3.","PeriodicalId":9203,"journal":{"name":"Brazilian Journal of Radiation Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90416535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Toxicity Removal of Pharmaceuticals Mixtures through Electron Beam Irradiation 电子束辐照药物混合物的毒性去除

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-04 DOI: 10.15392/2319-0612.2022.1838

N. F. Boiani, Flávio Kiyoshi Tominaga, Sueli Ivone Borrely

{"title":"Toxicity Removal of Pharmaceuticals Mixtures through Electron Beam Irradiation","authors":"N. F. Boiani, Flávio Kiyoshi Tominaga, Sueli Ivone Borrely","doi":"10.15392/2319-0612.2022.1838","DOIUrl":"https://doi.org/10.15392/2319-0612.2022.1838","url":null,"abstract":"Contamination of the aquatic environment by pharmaceuticals is becoming a global phenomenon of growing concern. Pharmaceuticals can be only partially metabolized during therapeutic use, resulting in the excretion and release of residual fractions into sewage, unaltered or in the form of metabolites they may remain active in sewage treatment facilities for a long time. Many studies have shown that wastewater treatment plants are not designed to eliminate these compounds, as such the main source of drug residues in the aquatic environment. Due to their frequency and detection in the environment, persistence and toxicity, the most studied pharmaceutical groups are antibiotics, psychiatric drugs, hormones, analgesics and anti-inflammatory, β-blockers, and antidiabetic drugs. Advanced Oxidative Processes (AOPs) have been applied as an alternative or complement to conventional sewage treatment processes, aiming the degradation and removal of toxic pollutants. Electron beam irradiation (EBI) is considered a clean process that offers an environmentally friendly alternative to degrade pollutants in the aquatic environment. This technology has been demonstrated effective for removal of multiclass pharmaceutical residues present in wastewater by using low doses (2.5-5.0 kGy). In this present study, we focused on toxicity removal of three different tertiary mixtures of pharmaceuticals, which showed toxicity removal efficiency around 80% for the mixture of Propranolol, Fluoxetine and Diclofenac; 75% for the mixture of Propranolol, Fluoxetine and Sulfadiazine; and 30% for the mixture of Acetylsalicylic acid, Fluoxetine and Metformin. \u0000 ","PeriodicalId":9203,"journal":{"name":"Brazilian Journal of Radiation Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80778701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characterization of suspended particulate matter using cascade impactor and X-ray fluorescence 用级联冲击器和x射线荧光表征悬浮颗粒物

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-04 DOI: 10.15392/2319-0612.2022.1919

J. Pereira, V. Costa, M. Anjos, Joaquim Teixeira de Assis

{"title":"Characterization of suspended particulate matter using cascade impactor and X-ray fluorescence","authors":"J. Pereira, V. Costa, M. Anjos, Joaquim Teixeira de Assis","doi":"10.15392/2319-0612.2022.1919","DOIUrl":"https://doi.org/10.15392/2319-0612.2022.1919","url":null,"abstract":"Atmospheric pollution has become one of the biggest environmental and public health problems in large urban centers. The process of industrialization and urbanization of large cities together with population growth and motorized transport has caused an increase in the level of air pollution in these places. Thus, this work approaches the characterization of suspended particulates in the surroundings of the Duque de Caxias Refinery (REDUC) from the identification of the chemical elements present using the X-ray fluorescence technique - XRF. A PIXE 8-stage impactor was used to collect the particulate material (aerodynamic diameters of 16 – 0.12 µm). On the other hand, the experimental measurements of XRF were performed using a commercial system ARTAX 200 (Bruker) and under the following conditions: voltage of 45 kV, current of 500 µA, acquisition time of 300 s and no filter in the incident X-ray beam. The study allowed estimating the dimensions of the particulate materials, identifying the chemical elements present and pointing out possible sources, from samples collected in three residential points that are in the surroundings of REDUC in the region of Campos Elísios. The X-ray fluorescence technique proved to be efficient and it was possible to detect the following chemical elements: Silicon, Sulfur, Chlorine, Potassium, Calcium, Titanium, Manganese, Iron, Nickel and Zinc. Correlations were observed between some elements making it possible to identify possible sources of pollution.","PeriodicalId":9203,"journal":{"name":"Brazilian Journal of Radiation Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91075455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Degradation and Toxicity of Amoxicillin After Electron Beam Irradiation 电子束辐照后阿莫西林的降解及毒性研究

Brazilian Journal of Radiation Sciences Pub Date : 2022-12-04 DOI: 10.15392/2319-0612.2022.1894

Sueli Ivone Borrely, Marcelo Miyada Redígolo, Bruno David Quiroz Villardi, Daniel Temponi Lebre, Flávio Kiyoshi Tominaga

引用次数: 0