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Kilian, Krzysztof, e Krystyna Pyrzyńska. "Scandium Radioisotopes—Toward New Targets and Imaging Modalities". Molecules 28, n.º 22 (19 de novembro de 2023): 7668. http://dx.doi.org/10.3390/molecules28227668.
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The concept of theranostics uses radioisotopes of the same or chemically similar elements to label biological ligands in a way that allows the use of diagnostic and therapeutic radiation for a combined diagnosis and treatment regimen. For scandium, radioisotopes -43 and -44 can be used as diagnostic markers, while radioisotope scandium-47 can be used in the same configuration for targeted therapy. This work presents the latest achievements in the production and processing of radioisotopes and briefly characterizes solutions aimed at increasing the availability of these radioisotopes for research and clinical practice.
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Motahari, Sayed Mahdi, e Fatemah Alemzada. "Radiopharmaceuticals: Production, Physics, and Clinical Applications in Nuclear Medicine: A Short Review". Afghanistan Journal of Basic Medical Science 2, n.º 2 (15 de abril de 2024): 43–52. http://dx.doi.org/10.62134/ajbms/v2.i2.khatamuni.6.
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Introduction: The use of radioactive atoms in medicine is growing, particularly in nuclear medicine, where radiation is emitted from the body. Radiopharmaceuticals or radiotracers are artificial short-living radioisotopes labeled with special pharmaceuticals. There are around 1800 radioisotopes, but only around 200 are suitable for general applications. There are four methods for generating radioisotopes: reactor-producing, neutron activation, charged acceleration, and radioisotope generators. Cyclotrons are used to produce many other radioisotopes for medical applications. Physical and biomedical characteristics are crucial for radiopharmaceuticals for clinical use. Physical aspects include the type and energy of radiation, mother and daughter radioactive elements, purity, and half-life of radioactives. Biomedical considerations include easy adhesion to biomolecules, a dynamic time course in the body, toxicity, and high tissue targeting. Radiopharmaceuticals used in diagnosis differ from those used in therapy, with positron emission tomography (PET) using radioisotopes, and gamma-emitting radioisotope-labeled radiopharmaceuticals suitable for SPECT imaging. Over 90% of radiopharmaceuticals are used for diagnostic purposes. Conclusion: Nuclear medicine, as an inevitable part of modern medicine, follows different methods to create more effective diagnostic and therapeutic radiopharmaceuticals with respect to several physical and biological considerations.
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Pimlott, Sally L. "Radioisotopes for medical imaging". International Journal of Modern Physics A 29, n.º 14 (26 de maio de 2014): 1441003. http://dx.doi.org/10.1142/s0217751x14410036.
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Nunes, Bruno Silveira, Enio Rodrigo Fernandes Rodrigues, Jonathan Alexander Prestes Fruscalso, Roger Pizzato Nunes, Alexandre Bonatto e Mirko Salomón Alva-Sánchez. "Highly Enriched Uranium-Free Medical Radioisotope Production Methods: An Integrative Review". Applied Sciences 12, n.º 24 (8 de dezembro de 2022): 12569. http://dx.doi.org/10.3390/app122412569.
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The ever-growing need for radiopharmaceuticals, i.e., compounds containing pharmaceutical drugs and radioisotopes used for medical diagnostic imaging (SPECT/PET scan) and treating neoplasms, is significantly leading to an increased demand for such substances in hospitals and clinics worldwide. Currently, most large-scale productions of radioisotopes required for radiopharmaceuticals are carried out in research reactors, via the fission of highly enriched uranium. However, because large amounts of radioactive waste are produced as byproducts in this process, new greener methods are needed for radioisotope production. This work presents an integrative literature review and summarizes enriched uranium-free methods for radioisotope production, accomplished through the adoption of new reaction routes, distinct acceleration technologies, or by using other physical processes. This review considered forty-eight studies published from 2010 to 2021 on three established virtual databases. Among these selected works, a cyclotron is the most adopted HEU-free method for radioisotope production, and 44Sc, 68Ga, and 99mTc are the medical radioisotopes most often reported as produced by using the investigated HEU-free production methods.
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Perini, Efrain Araujo, Mikhail Skopchenko, Tran Thu Hong, Rahmat Harianto, Alexis Maître, Maidelys Rosa Rodríguez Rodríguez, Nathalia de Oliveira Santos et al. "Pre-feasibility Study for Establishing Radioisotope and Radiopharmaceutical Production Facilities in Developing Countries". Current Radiopharmaceuticals 12, n.º 3 (1 de outubro de 2019): 187–200. http://dx.doi.org/10.2174/1874471012666190328164253.
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Background:A significant number of developing countries have no facilities to produce medical radioisotopes and radiopharmaceuticals.Objective:In this paper we show that access to life-saving radioisotopes and radiopharmaceuticals and the geographical distribution of corresponding infrastructure is highly unbalanced worldwide.Methods:We discuss the main issues which need to be addressed in order to establish the production of radioisotopes and radiopharmaceuticals, which are especially important for developing countries as newcomers in the field. The data was gathered from several sources, including databases maintained by the International Atomic Energy Agency (IAEA), World Health Organization (WHO), and other international organizations; personal interactions with representatives in the nuclear medicine field from different regions of the world; and relevant literature.Results:Developing radioisotope and radiopharmaceutical production program and installing corresponding infrastructure requires significant investments, both man-power and financial. Support already exists to help developing countries establish their medical radioisotope production installations from several organizations, such as IAEA.Conclusion:This work clearly shows that access to life-saving radioisotopes and the geographical distribution of corresponding infrastructure is highly unbalanced. Technology transfer is important as it not only immediately benefits patients, but also provides employment, economic activity and general prosperity in the region to where the technology transfer is implemented.
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Konefał, Adam, Andrzej Orlef e Maria Sokół. "Application of therapeutic linear accelerators for the production of radioisotopes used in nuclear medicine". Polish Journal of Medical Physics and Engineering 28, n.º 3 (28 de julho de 2022): 107–16. http://dx.doi.org/10.2478/pjmpe-2022-0013.
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Abstract This review paper summarizes the possibilities of the use of therapeutic linear electron accelerators for the production of radioisotopes for nuclear medicine. This work is based on our published results and the thematically similar papers by other authors, directly related to five medical radioisotopes as 99Mo/99mTc, 198Au, 186Re, 188Re, 117mSn, produced using therapeutic linacs. Our unpublished data relating to the issues discussed have also been used here. In the experiments, two types of radiation were included in the analysis of the radioisotope production process, i.e. the therapeutic twenty-megavolt (20 MV) X-rays generated by Varian linacs and neutron radiation contaminating the therapeutic beam. Thus, the debated radioisotopes are produced in the photonuclear reactions and in the neutron ones. Linear therapeutic accelerators do not allow the production of radioisotopes with high specific activities, but the massive targets can be used instead. Thus, the amount of the produced radioisotopes may be increased. Apart from linear accelerators, more and more often, the production of radioisotopes is carried out in small medical cyclotrons. More such cyclotrons are developed, built, and sold commercially than for scientific research. The radioisotopes produced with the use of therapeutic linacs or cyclotrons can be successfully applied in various laboratory tests and in research.
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Kambali, Imam, Indra Saptiama e Hari Suryanto. "Residual Radioisotopes Generated from Neutron Irradiated Aluminum Capsules". Aceh International Journal of Science and Technology 6, n.º 3 (31 de dezembro de 2017): 104–10. http://dx.doi.org/10.13170/aijst.6.3.8116.
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Aluminum (Al) is often used to house a molybdenum oxide (MoO3) target for neutron or proton-produced technetium-99m (99mTc) radioisotope. During neutron or proton bombardment of an Al body, residual radioisotopes could be generated following nuclear reactions between the incoming particles and the Al body. In this research, residual radioisotopes produced following nuclear reactor based-neutron irradiation of Al body were experimentally measured using a portable gamma ray spectroscopy system; whereas TALYS 2015 calculated data were used to evaluate various nuclear reactions for the by-product identification. As a comparison, Al body used in a cyclotron-based 99mTc production was also analyzed. Experimental data indicated that relatively long-lived radioisotopes such as 26Al, 22Na and 24Na were identified in the Al body following nuclear reactor-based 99mTc production, whereas the presence of 27Mg radioisotope was, for the first time, experimentally detected in both the Al bodies for nuclear reactor-based and cyclotron-based 99mTc production. A special safety attention should be paid to the radiation workers when producing 99mTc using a nuclear reactor since it generates 26Al (half life = 716,600 years).
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Lapi, Suzanne E., e Jonathan W. Engle. "Radiochlorine: an underutilized halogen tool". Radiochimica Acta 107, n.º 9-11 (25 de setembro de 2019): 1027–31. http://dx.doi.org/10.1515/ract-2019-0015.
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Abstract Halogen radioisotopes have a variety of physical half-lives which are suitable for probing a wide variety of pharmacokinetic processes. Compared with other radiohalogens, relatively little work has been done with radiochlorine. However, high specific activity radioisotopes of chlorine are available from low energy cyclotron production in quantities suitable for positron emission tomography (PET) and fundamental research. In particular, the sole radioisotope of chlorine which may be used for PET imaging, 34mCl, has achieved a state of development that permits imaging in clinical settings though sparse research effort has been focused on this isotope over the last 40 years. Additionally, the other longer-lived radioisotopes of chlorine will likely continue to show utility for more traditional radiotracer studies and chemistry development.
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Pellico, Juan, Jordi Llop, Irene Fernández-Barahona, Riju Bhavesh, Jesús Ruiz-Cabello e Fernando Herranz. "Iron Oxide Nanoradiomaterials: Combining Nanoscale Properties with Radioisotopes for Enhanced Molecular Imaging". Contrast Media & Molecular Imaging 2017 (2017): 1–24. http://dx.doi.org/10.1155/2017/1549580.
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The combination of the size-dependent properties of nanomaterials with radioisotopes is emerging as a novel tool for molecular imaging. There are numerous examples already showing how the controlled synthesis of nanoparticles and the incorporation of a radioisotope in the nanostructure offer new features beyond the simple addition of different components. Among the different nanomaterials, iron oxide-based nanoparticles are the most used in imaging because of their versatility. In this review, we will study the different radioisotopes for biomedical imaging, how to incorporate them within the nanoparticles, and what applications they can be used for. Our focus is directed towards what is new in this field, what the nanoparticles can offer to the field of nuclear imaging, and the radioisotopes hybridized with nanomaterials for use in molecular imaging.
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Usman, Ahmed Rufai, e Ibrahim Abdullahi Lawal. "PROGRESS IN NICKEL TARGET DESIGNS FOR DEUTERON IRRADIATION: A MILESTONE IN RADIOISOTOPE PRODUCTION OPTIMIZATION". FUDMA JOURNAL OF SCIENCES 6, n.º 5 (31 de outubro de 2022): 211–14. http://dx.doi.org/10.33003/fjs-2022-0605-1484.
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Medical radioisotopes play significant roles in nuclear medicine, particularly in tumor diagnosis and its therapy. Optimization in production of these important isotopes is very essential for the overall health of the target patients. In this work, we analyzed general trends in the use of various forms of nickel metal as target for radioisotopes production in nuclear accelerators. A careful study of all previously used forms of nickel metal in the literature up to 2016 indicate that different physical forms of the metal, such as its very high purity and impure forms, alloys, compounds and powdered forms have, over the years, been used for various radioisotope productions under deuteron irradiation route, each providing different production effect. The excitation functions of several useful radioisotopes could be studied under deuteron irradiation of nickel. In a recent experimental work by the authors, some very pure, thin nickel foils of natural isotopic composition were also used in form of stacked arrangement for deuteron irradiation. The study found that most of the recent studies on radioisotopes production cross sections use very high purity and solid nickel forms.
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Usman, Ahmed Rufai, e Ibrahim Abdullahi Lawal. "PROGRESS IN NICKEL TARGET DESIGNS FOR DEUTERON IRRADIATION: A MILESTONE IN RADIOISOTOPE PRODUCTION OPTIMIZATION". FUDMA JOURNAL OF SCIENCES 7, n.º 2 (30 de abril de 2023): 121–24. http://dx.doi.org/10.33003/fjs-2023-0702-1718.
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Medical radioisotopes play significant roles in nuclear medicine, particularly in tumor diagnosis and its therapy. Optimization in production of these important isotopes is very essential for the overall health of the target patients. In this work, we analyzed general trends in the use of various forms of nickel metal as target for radioisotopes production in nuclear accelerators. A careful study of all previously used forms of nickel metal in the literature up to 2016 indicate that different physical forms of the metal, such as its very high purity and impure forms, alloys, compounds and powdered forms have, over the years, been used for various radioisotope productions under deuteron irradiation route, each providing different production effect. The excitation functions of several useful radioisotopes could be studied under deuteron irradiation of nickel. In a recent experimental work by the authors, some very pure, thin nickel foils of natural isotopic composition were also used in form of stacked arrangement for deuteron irradiation. The study found that most of the recent studies on radioisotopes production cross sections use very high purity and solid nickel forms.
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Acosta, Luis, Paulina Amador-Valenzuela, Eduardo Andrade, Libertad Barrón-Palos, David Belmont, Luis E. Charón, Efraín Chávez et al. "The AMS technique as an important tool for the measurement of astrophysical cross sections". EPJ Web of Conferences 252 (2021): 05003. http://dx.doi.org/10.1051/epjconf/202125205003.
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Accelerator Mass Spectrometry is a technique commonly used to approach low concentrations of certain long half-life radioisotopes. The most important contribution of the technique is the accurate measure of organic sample ages, by separating masses 12,13 and 14 in the case of carbon allocated in such samples. However, the reach of AMS could cover many other scientific scopes, since it can give us a precise measure of a very small concentration of a radioisotope. On this direction, AMS can be used to approach reactions of interest for astrophysics, if we spot an specific radioisotope which concentration can be measure with AMS. Starting with this, we have selected specific reactions involving 14C, 10Be and 26Al, produced with slow neutrons from a reactor and positive ions at an accelerator. The main idea is to produce a particular reaction and later to measure the radioisotopic concentration using AMS. In this study our first results for 14C and 10Be nuclei produced with neutrons, and the preliminary results for 26Al nuclei produced with deuterium are shown.
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LaBrecque, J. J., e P. A. Rosales. "The Application of P-32 and Sn-113 Radionuclides for the Determination of Noble Metals". Advances in X-ray Analysis 32 (1988): 255–59. http://dx.doi.org/10.1154/s0376030800020553.
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Recently, a new radioisotope X-ray fluorescence technique was reported in which a small quantity (100μCi) of a selected radioisotope was directly mixed with a small amount of the sample, as a source-sample. Many different types of excitation radiation from various radioisotopes have been previously studied: Na-22, S-35, Fe-55, Co-57, Hi-63, Zn-65, Cd-109, 1-125, Cs-137, Pa-147 and Ara-241.
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KARPUZ DEMİR, Nurdan. "Investigation of the Cross Sections and Effect of Level Density Models for Platinum Element". Afyon Kocatepe University Journal of Sciences and Engineering 22, n.º 6 (28 de dezembro de 2022): 1256–70. http://dx.doi.org/10.35414/akufemubid.1143137.
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In cases where experimental studies cannot be carried out and there is no experimental data with it, studies carried out with theoretical models shed light on the researchers' knowledge of different data. The most important of this data is the measurable or calculatable influence cross-section value, which is defined as the probability of a reaction occurrence. Examining the possible effects of different models in the calculation of the effect section is important for the correct calculation of this value. The most important data, the cross section of influence, has taken its place in the radioisotope world as well as in many areas of nuclear physics. With developing technology and advancing science, radioisotopes have widespread and diversified uses. Most commonly, radioisotopes are used in medical diagnosis and treatment applications. Among the many radioisotopes used for this purpose, 191-199Au radioisotopes are also important in terms of both their benefits and characteristics in medical applications. In this respect, the study aimed to investigate the effects of different nuclear level density models in production impact cross-section calculations of 191-199Au radioisotopes with deuteron reference. Theoretical cross sections using the TALYS code have been simulated for all isotopes. The results of the calculations obtained were compared with each other and with the experimental data in the literature and it was aimed to determine the most compatible level density models according to the reaction situations examined.
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Khan, Hamda, Umair Aziz e Zafar Ullah Koreshi. "Radiation dose delivered by 125I, 103Pd and 131Cs and dose enhancement by gold nanoparticle (GNP) solution in prostate brachytherapy: a comparative analysis by Monte Carlo simulation". IIUM Engineering Journal 20, n.º 2 (2 de dezembro de 2019): 176–87. http://dx.doi.org/10.31436/iiumej.v20i2.1136.
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: The energy deposition and radiation dose from commonly used radioisotopes, 125I,103Pd, and 131Cs, used for brachytherapy of cancers is estimated using Monte Carlo (MC) simulations. To enhance the dose, gold nanoparticle (GNP) solutions are injected into the tumor; this results in more effective and shorter therapy duration. It is thus important to estimate the dose enhancement factor (DEF) achievable by a radioisotope. The research presented in this paper thus focuses on a comparative analysis of radioisotopes. To estimate the radiation dose, the Monte Carlo N-particle code MCNP5 was used for a coupled photon-electron simulation of radiation transport from radiation emanating from seeds of radioisotopes implanted in the prostate at positions prescribed to deliver effective doses to the tumor while protecting neighbouring vital organs such as the rectum and urethra. The quantities tallied were the energy deposition (F6 tally) and the pulse heights (*F8 tally) in specified energy bins. The energy deposited in the tumor was used to estimate the absorbed dose to the prostate incorporating the transformations of the radioisotopes during decay. The absorbed dose was subsequently estimated for a GNP-tissue solution with a concentration of 25 mg Au/g of prostate tissue, modelled as a homogenous mixture. From the simulations, it was found that the lifetime absorbed dose is ~96 Gy from 98 seeds, each of 0.31 mCi, of 125I; ~102 Gy, from 115 seeds, each of 1.4 mCi, of 103Pd, and ~90 Gy from 131Cs seeds replacing 103Pd seeds of the same initial activity. The main advantage of 131Cs, over 125I and 103Pd, is observed in the larger dose rate (~26 cGy/hr) delivered initially i.e. in the first few days which is 1.5 and 5.7 times higher than that for 103Pd and 125I. The absorbed dose for 125I, 103Pd and 131Cs increases to ~245, ~130, ~187 Gy respectively with GNP-tissue solution of 25 mg Au/g tissue. From the analysis, it is found that while the lifetime absorbed dose of all three radioisotopes is of the same order, there are advantages in using 131Cs; these advantages are further quantified.
ABSTRAK: Pemendapan tenaga dan dos sinaran radiasi daripada radioisotop yang biasa digunakan, 125I,103Pd, dan 131Cs, digunakan bagi terapibraki kanser dianggar menggunakan simulasi Monte Carlo (MC). Bagi meningkatkan dos, larutan partikel nano emas (GNP) telah disuntik ke dalam tumor; ini lebih memberi kesan dan mengurangkan masa terapi. Oleh itu, adalah penting menganggar faktor dos penggalak (DEF) dapat dicapai dengan radioisotop. Kajian ini mengfokuskan pada analisis perbandingan radioisotop. Bagi menganggarkan dos radiasi, kod Monte Carlo N-partikel MCNP5 telah digunakan pada simulasi pasangan foton-elektron pengangkutan radiasi daripada pancaran radioaktif benih radioisotop yang ditanam dalam prostat pada posisi yang disebut bagi mencetuskan dos penghantaran yang berkesan pada sel tumor. Dalam masa sama melindungi organ penting seperti rektum dan uretra. Kuantiti diselaras dengan pemendapan tenaga (selaras F6) dan ketinggian denyut (selaras *F8) dalam aras tenaga sebenar. Tenaga yang dienap dalam sel tumor ini telah digunakan bagi menganggarkan dos serapan pada prostat dengan menggabungkan transformasi radioisotop ketika susutan. Dos yang diserap telah kemudiannya dianggarkan bagi larutan tisu-GNP dengan ketumpatan 25 mg Au/g tisu prostat, dimodelkan sebagai campuran homogen. Daripada simulasi, dapatan kajian menunjukkan dos diserap sebanyak ~96 Gy daripada 98 benih, setiap satu daripada 0.31 mCi, 125I; ~102 Gy, dari 115 benih, setiap 1.4 mCi, dari 103Pd, dan ~90 Gy daripada benih 131Cs menggantikan benih 103Pd pada pemulaan aktiviti yang sama. Keistimewaan utama adalah 131Cs, ke atas 125I dan 103Pd, telah dilihat dalam kadar dos lebih besar (~26 cGy/hr) dikeluarkan pada pemulaannya iaitu dalam beberapa hari pertama iaitu 1.5 dan 5.7 kali lebih tinggi daripada 103Pd dan 125I. Dos yang diserap pada 125I, 103Pd dan 131Cs bertambah kepada ~245, ~130, ~187 Gy masing-masing dengan larutan tisu-GNP sebanyak 25 mg Au/g tisu. Hasil analisis menunjukkan penyerapan seumur hidup dos diserap pada ketiga-ketiga radioisotop dalam aturan yang sama, ini adalah keistimewaan menggunakan 131Cs; keistimewaan ini akan terus diuji pada masa depan dan diukur kuantitinya.
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Setiawan, Duyeh, e Titin Sri Mulyati. "PEMBUATAN DAN ANALISIS FISIKO-KIMIA RADIOISOTOP SKANDIUM-47 (47Sc) DARI BAHAN SASARAN TITANIUM OKSIDA ALAM". Jurnal Sains dan Teknologi Nuklir Indonesia 16, n.º 2 (19 de agosto de 2015): 63. http://dx.doi.org/10.17146/jstni.2015.16.2.2379.
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Radioisotop skandium-47 (47Sc) memiliki waktu paruh 3,35 hari, pemancar energi beta, Eβmax 0,441 MeV (68 %) dan 0,601 MeV (32 %), serta pemancar energi gamma, Eγ 159 keV (68 %). Radioisotop 47Sc dihasilkan oleh iradiasi neutron cepat dari target titanium berdasarkan reaksi inti 47Ti (n, p) 47Sc. Metode pemisahan 47Sc menggunakan cara kromatografi kolom dengan matriks Dowex AG 50W-x4 dalam bentuk kation (H+), selanjutnya 47Sc dielusi dengan HCl 4 M. Radioisotop 47Sc digunakan dalam bidang kedokteran nuklir untuk radioterapi dengan metode pencitraan. Karakteristik fisiko-kimia suatu sediaan radioisotop mempunyai peranan penting dalam penyebaran dan penimbunan di dalam tubuh. Oleh karena itu, untuk menjamin keberhasilan penggunaan sediaan radioisotop 47Sc perlu dilakukan analisis fisiko-kimia yang meliputi kejernihan, pH, kemurnian radionuklida dan radiokimia serta stabilitasnya pada penyimpanan. Hasil penelitian menunjukkan bahwa radio-isotop 47Sc berupa larutan jernih dengan rumus kimia 47Sccl3, memiliki pH 2, konsentrasi radioaktivitas 1,086 ± 0,0314 mCi/mL, aktivitas jenis 2,60 mCi/mg Ti (End of Irradiation = EOI), kemurnian radionuklida lebih dari 98,5 %, kemurnian radiokimia 95,22 ± 0,83 % dan masih stabil selama 5 hari disimpan di temperatur kamar. Radioisotop 47Sc yang diperoleh memiliki karakteristik fisiko-kimia untuk digunakan dalam pengembangan radiofarmaka sebagai sediaan radioterapi. PREPARATION AND PHYSICO-CHEMICAL ANALYSIS OF RADIOISOTOPE SCANDIUM-47 (47Sc) FROM NATURAL TITANIUM OXIDE MATERIAL TARGET. Radioisotopes scandium-47 (47Sc) has a half-life of 3.35 day, the energy beta transmitter Eβmax of 0.441 MeV (68 %) and 0.601 MeV (32 %), as well as gamma energy transmitter, Eγ 159 keV (68 %). Radioisotope 47Sc is produced by fast neutron irradiation of the titanium targets based on nuclear reaction 47Ti (n,p) 47Sc. Separation methods of 47Sc was done using chromatography column with a matrix of Dowex AG 50W-x4 in a cation (H+) form, and 47Sc was eluted with 4 M HCl. Radioisotope 47Sc is used in nuclear medicine for radiotherapy with imaging methods. The physico-chemical characteristics of a radioisotope has an important role in the biodistribution and bioaccumulation in the body. Therefore, in order to assure the success of usage of radioisotope 47Sc, of physico-chemical characteristic is need to be analyzed which includes clarity of solution, pH, purity of radionuclide and radiochemical, stability in the storage. The results showed that the radioisotope 47Sc was a clear solution with a chemical formula of 47ScCl3, has pH of 2 with the concentration of radioactivity 1,086 ± 0,0314 mCi/mL, specific activity of 2.60 mCi/mg Ti (End of Irradiation = EOI), the radionuclide purity more than 98.50 %, radiochemical purity 95,22 ± 0,83 % and stable after 5 days storage in room temperature. Radioisotope 47Sc that was produced has the ideal physico-chemical characteristics and can be used for the radiopharmaceutical development especially for radiotherapy.
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Molo, Yosefina, Bartholomeus Pasangka e Jehunias Leonidas Tanesib. "INVESTIGASI KANDUNGAN RADIOISOTOP DALAM SAMPEL BATUAN DI MUARA SUNGAI SUMLILI KUPANG BARAT". Jurnal Fisika : Fisika Sains dan Aplikasinya 5, n.º 1 (15 de abril de 2020): 11–18. http://dx.doi.org/10.35508/fisa.v5i1.1235.
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Abstrak
Masalah pokok yang dikaji di penelitian ini adalah pemetaan dan analisis aktivitas jenis kandungan radioisotop dalam sampel batuan di muara sungai Sumlili Kupang Barat. Tujuan penelitian meliputi : menentukanrange cacah dan aktivitas jenis massa (C) kandungan radioisotop dalam sampel pasir di muara sungai Sumlili Kupang Barat, mengestimasi tingkat kontaminasi radioisotop sesuai standar di sekitar muara sungai Sumlili, dan memetakan sebaran cacah radioisotop pada luasan daerah tertentu yang terjangkau survei di lapangan. Metode penelitian meliputi : observasi/survei, sampling, serta analisis dan interpretasi data. Kisaran cacah radiasi di lapangan, di laboratorium, dan nilai aktivitas jenis massa kandungan radioisotop dalam 52 sampel pasir dari lokasi penelitian dimuara sungai Sumili Kupang Barat secara berturut-turut adalah 19 cpm sampai dengan 60 cpm, 29 cpm sampai dengan 73 cpm, dan 0,107 x 10-5μCi/gram sampai dengan 0,269 x 10-5μCi/gram. Berdasarkan kontur dan kurva tiga dimensi radiasi cacah radioisotop dalam sampel pasir di lapangan dan di laboratorium serta kontur dan kurva tiga dimensi aktivitas jenis massa di muara sungai Sumlili Kupang Barat dapat diketahui bahwa sebaran kontaminasi radioisotop di muara sungai Sumlili Kupang Barat lebih tinggi ke arah barat dan cenderung menurun ke arah timur. Hasil perhitungan aktivitas jenis massa kandungan radioisotop dalam sampel pasir di muara sungai Sumlili Kupang Barat, termaksud dalam kontaminasi rendah untuk radiasi alpha (α) dan beta (β), namun daerah ini perlu diwaspadai karna terdapat beberapa titik di lapangan, cacah radiasi nuklir kandungan radioisotop dalam deposit mineral cukup tinggi melebihi standar IAEA.
Kata kunci : Radioisotop, Aktivitas Jenis Massa, Daerah Kontaminasi.
ABSTRACT
The main problem studied in this study is mapping and analyzing the activity of the types of radioisotope content in rock samples at the mouth of the Sumlili river in West Kupang. The research objectives included: determining the counting range and mass type activity (C) radioisotope content in the sand samples at the Sumlili River mouth in West Kupang, estimating the level of radioisotope contamination according to the standards around the Sumlili river estuary, and mapping the distribution of radioisotope counts in the area covered by surveys in field. Research methods include: observation / survey, sampling, and analysis and interpretation of data. The range of radiation counts in the field, in the laboratory, and the value of the type of mass activity of radioisotope content in 52 sand samples from the study locations in the West Kupang Sumili River are 19 cpm to 60 cpm, 29 cpm to 73 cpm, and 0.107 x 10-5μCi / gram up to 0.269 x 10-5μCi / gram. Based on the three-dimensional contour and curve of radiation from radioisotope counts in sand samples in the field and in the laboratory and three-dimensional contours and curves the activity of mass types in the Sumlili estuary of West Kupang can be seen that the distribution of radioisotope contamination in the Sumlili estuary of West Kupang is higher west and tends to decline to the east. The results of the calculation of the type of mass activity of radioisotope content in sand samples at the mouth of the Sumlili River in West Kupang, are referred to in low contamination for alpha (α) and beta (β) radiation, but this area needs to be watched out for there are several points in the field, nuclear radiation in mineral deposits quite high exceeding IAEA standards.
Keywords : Radioisotopes, Mass Type Activities, Contamination Areas.
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Martini, Petra, Andrea Adamo, Neilesh Syna, Alessandra Boschi, Licia Uccelli, Nopphon Weeranoppanant, Jack Markham e Giancarlo Pascali. "Perspectives on the Use of Liquid Extraction for Radioisotope Purification". Molecules 24, n.º 2 (18 de janeiro de 2019): 334. http://dx.doi.org/10.3390/molecules24020334.
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The reliable and efficient production of radioisotopes for diagnosis and therapy is becoming an increasingly important capability, due to their demonstrated utility in Nuclear Medicine applications. Starting from the first processes involving the separation of 99mTc from irradiated materials, several methods and concepts have been developed to selectively extract the radioisotopes of interest. Even though the initial methods were based on liquid-liquid extraction (LLE) approaches, the perceived difficulty in automating such processes has slowly moved the focus towards resin separation methods, whose basic chemical principles are often similar to the LLE ones in terms of chelators and phases. However, the emerging field of flow chemistry allows LLE to be easily automated and operated in a continuous manner, resulting in an even improved efficiency and reliability. In this contribution, we will outline the fundamentals of LLE processes and their translation into flow-based apparatuses; in addition, we will provide examples of radioisotope separations that have been achieved using LLE methods. This article is intended to offer insights about the future potential of LLE to purify medically relevant radioisotopes.
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Duong, Van Dong, Ngoc Dien Pham, Van Cuong Bui, Phuoc Tho Mai, Thi Thu Nguyen e Cam Hoa Vo Thi. "Production of Radioisotopes and Radiopharmaceuticals at the Dalat Nuclear Research Reactor". Nuclear Science and Technology 4, n.º 1 (30 de março de 2014): 46–56. http://dx.doi.org/10.53747/jnst.v4i1.213.
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After reconstruction, the Dalat Nuclear Research Reactor (DNRR) was inaugurated on March 20th, 1984 with the nominal power of 500 kW. Since then the production of radioisotopes and labelled compounds for medical use was started. Up to now, DNRR is still the unique one in Vietnam. The reactor has been operated safely and effectively with the total of about 37,800 hrs (approximately 1,300 hours per year). More than 90% of its operation time and over 80% of its irradiation capacity have been exploited for research and production of radioisotopes. This paper gives an outline of the radioisotope production programme using the DNRR. The production laboratory and facilities including the nuclear reactor with its irradiation positions and characteristics, hot cells, production lines and equipment for the production of Kits for labelling with 99mTc and for quality control, as well as the production rate are mentioned. The methods used for production of 131I, 99mTc, 51Cr, 32P, etc. and the procedures for preparation of radiopharmaceuticals are described briefly. Status of utilization of domestic radioisotopes and radiopharmaceuticals in Vietnam is also reported.
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Islam, Md Rafiqul, Mehrdad Shahmohammadi Beni, Shigeki Ito, Shinichi Gotoh, Taiga Yamaya e Hiroshi Watabe. "An Analysis Scheme for 3D Visualization of Positron Emitting Radioisotopes Using Positron Emission Mammography System". Applied Sciences 12, n.º 2 (14 de janeiro de 2022): 823. http://dx.doi.org/10.3390/app12020823.
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Proton range monitoring and verification is important to enhance the effectiveness of treatment by ensuring that the correct dose is delivered to the correct location. Upon proton irradiation, different positron emitting radioisotopes are produced by the inelastic nuclear interactions of protons with the target elements. Recently, it was reported that the 16O(p,2p2n)13N reaction has a relatively low threshold energy, and it could be potentially used for proton range verification. In the present work, we have proposed an analysis scheme (i.e., algorithm) for the extraction and three-dimensional visualization of positron emitting radioisotopes. The proposed step-by-step analysis scheme was tested using our own experimentally obtained dynamic data from a positron emission mammography (PEM) system (our developed PEMGRAPH system). The experimental irradiation was performed using an azimuthally varying field (AVF) cyclotron with a 80 MeV monoenergetic pencil-like beam. The 3D visualization showed promising results for proton-induced radioisotope distribution. The proposed scheme and developed tools would be useful for the extraction and 3D visualization of positron emitting radioisotopes and in turn for proton range monitoring and verification.
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Vretenar, M., A. Mamaras, G. Bisoffi e P. Foka. "Production of radioisotopes for cancer imaging and treatment with compact linear accelerators". Journal of Physics: Conference Series 2420, n.º 1 (1 de janeiro de 2023): 012104. http://dx.doi.org/10.1088/1742-6596/2420/1/012104.
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Abstract Accelerator-produced radioisotopes are widely used in modern medicine, for imaging, for cancer therapy, and for combinations of therapy and diagnostics (theragnostics). Clinical trials are well advanced for several radioisotope-based treatments that might open the way to a strong request of specific accelerator systems dedicated to radioisotope production. While cyclotrons are the standard tool in this domain, we explore here alternative options using linear accelerators. Compared to cyclotrons, linacs have the advantage of modularity, compactness, and reduced beam loss with lower shielding requirements. Although in general more expensive than cyclotrons, linacs are competitive in cost for production of low-energy proton beams, or of intense beams of heavier particles. After a review of radioisotopes of potential interest, in particular produced with low-energy protons or helium, this paper presents two linac-based isotope production systems. The first is a compact RFQ-based system for PET (Positron Emission Tomography) isotopes, and the second is an alpha-particle linac for production of alpha-emitters. The accelerator systems are described, together with calculations of production yields for different targets.
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Entry, James A., e William H. Emmingham. "Sequestration of 137Cs and 90Sr from soil by seedlings of Eucalyptustereticotnis". Canadian Journal of Forest Research 25, n.º 6 (1 de junho de 1995): 1044–47. http://dx.doi.org/10.1139/x95-114.
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The ability of seedlings of Eucalyptustereticornis Smith to accumulate 137Cs and 90Sr, characteristic radioisotopes of nuclear fallout, from contaminated growth medium was tested. All seedlings were grown for 3 months in 165 cm3 of sphagnum peat moss–perlite (1:1 v/v) in a growth chamber before treatment with an isotope. After 1 month of exposure, seedlings had accumulated 31.0% of the 137Cs and 11.3% of the 90Sr originally present in the growth medium, with bioconcentration ratios of 54:1 for 137Cs and 13:1 for 90Sr. Accumulation of 137Cs and 90Sr in plant tissue was correlated curvilinearly with increasing time of exposure and with increasing concentration of radioisotope in the growth medium. Because seedlings of E. tereticornis accumulate these radioisotopes rapidly, they may be valuable in remediation of contaminated soils.
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Inacio, Pascoleta, Albert Zicko Johannes e Bartholomeus Pasangka. "INVESTIGASI KANDUNGAN RADIOISOTOP DALAM SAMPEL SUMBER MATA AIR DI DESA LALETEN KECAMATAN WELIMAN KABUPATEN MALAKA". Jurnal Fisika : Fisika Sains dan Aplikasinya 3, n.º 2 (17 de dezembro de 2018): 106–9. http://dx.doi.org/10.35508/fisa.v3i2.610.
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Abstrak
Telah dilakukan penelitian untuk memeriksa kandungan radioisotop dalam sampel sumber mata air di Desa Laleten Kecamatan Weliman Kabupaten Malaka. Penelitian ini bertujuan untuk menentukan interval dan tingkat aktivitas jenis massa kandungan radioisotop dari sumber air minum lokal dan kemudian dibandingkan dengan standar untuk tingkat kontaminasi dan standar ambang batas dosis radiasi yang diperbolehkan untuk persyaratan air minum (Permenkes RI). Metode yang digunakan dalam penelitian ini yaitu dengan metode sampling. Sampel dari lapanga dipanaskan dan dikeringkan di laboratorium setelah itu dicacah menggunakan alat Detektor Geiger Muller dalam jangka waktu 5 menit. Hasil penelitian ini menunjukkan interval aktivitas jenis massa dari sampel adalah 2,363 × 10-5 μCi/gram sampai dengan 9,455 × 10-5 μCi/gram. Tingkat kontaminasi radioisotop di lokasi penelitian tergolong daerah kontaminasi radiasi alpha sedang dan radiasi beta rendah. Sedangkan air yang bersumber dari mata air weliman tidak layak digunakan sebagai air minum berdasarkan standar Permenkes RI.
Kata kunci: Radioisotop, Aktivitas Jenis Massa, Daerah Kontaminasi, Dosis Radiasi, Air.
Abstract
[Title: Please Type Title of Article in English in here and Bold formated] Research has been conducted to examine the radioisotope content in spring water samples in Laleten Village, Weliman District, Malaka Regency. This study aims to determine the interval and the level of mass specific activity of radioisotope content from local drinking water sources and then compared with the standard for contamination levels and the standard for radiation dose thresholds allowed for drinking water requirements (Permenkes RI).The method used in this study is the sampling method. Samples from the fields are heated and dried in the laboratory after which they are counted using a Geiger Muller Detector for 5 minutes. The results of this study indicate the interval of mass specific activity from the sample is 2.363 × 10-5 μCi / gram up to 9.455 × 10-5 μCi / gram. The level of radioisotope contamination at the study site was classified as a medium-alpha radiation and low- beta radiation contamination area. Whereas water sourced from Weliman spring is not suitable for use as drinking water based on the Permenkes RI standard.
Keywords: Radioisotopes, Mass Specific Activities, Contamination Areas, Water, Radiation Doses.
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Jeon, Byoungil, Jongyul Kim, Yonggyun Yu e Myungkook Moon. "Comparison of Machine Learning-Based Radioisotope Identifiers for Plastic Scintillation Detector". Journal of Radiation Protection and Research 46, n.º 4 (30 de dezembro de 2021): 204–12. http://dx.doi.org/10.14407/jrpr.2021.00206.
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Background: Identification of radioisotopes for plastic scintillation detectors is challenging because their spectra have poor energy resolutions and lack photo peaks. To overcome this weakness, many researchers have conducted radioisotope identification studies using machine learning algorithms; however, the effect of data normalization on radioisotope identification has not been addressed yet. Furthermore, studies on machine learning-based radioisotope identifiers for plastic scintillation detectors are limited.Materials and Methods: In this study, machine learning-based radioisotope identifiers were implemented, and their performances according to data normalization methods were compared. Eight classes of radioisotopes consisting of combinations of 22Na, 60Co, and 137Cs, and the background, were defined. The training set was generated by the random sampling technique based on probabilistic density functions acquired by experiments and simulations, and test set was acquired by experiments. Support vector machine (SVM), artificial neural network (ANN), and convolutional neural network (CNN) were implemented as radioisotope identifiers with six data normalization methods, and trained using the generated training set.Results and Discussion: The implemented identifiers were evaluated by test sets acquired by experiments with and without gain shifts to confirm the robustness of the identifiers against the gain shift effect. Among the three machine learning-based radioisotope identifiers, prediction accuracy followed the order SVM >ANN>CNN, while the training time followed the order SVM>ANN>CNN.Conclusion: The prediction accuracy for the combined test sets was highest with the SVM. The CNN exhibited a minimum variation in prediction accuracy for each class, even though it had the lowest prediction accuracy for the combined test sets among three identifiers. The SVM exhibited the highest prediction accuracy for the combined test sets, and its training time was the shortest among three identifiers.
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Oddy, JM. "Radioisotopes". Biochemical Education 21, n.º 2 (abril de 1993): 114. http://dx.doi.org/10.1016/0307-4412(93)90078-e.
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Rabbani, AFM Masum, Md Shohag Mia, Hasan Mehdi, Sanchoy Chandra Biswasarma, Md Ariful Islam, Md Jashim Uddin, Tanvir Ahmed Biman, Mohammad Anwar Ul Azim e Md Nahid Hossain. "Optimization of 18F Radioisotope Production with Cyclone 18/9 MeV IBA Cyclotron Installed at NINMAS". Dhaka University Journal of Science 71, n.º 1 (29 de maio de 2023): 56–59. http://dx.doi.org/10.3329/dujs.v71i1.65273.
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A cyclotron is a particle accelerator, which employs electromagnetic fields to accelerate charged particles to extremely high speeds and energy. It is used to create radioisotopes for radiopharmaceuticals, which are used to diagnose and treat cancer. Because cyclotron-produced radiopharmaceuticals are exceptionally effective in identifying various cancers. Cyclotrons are fast evolving and will play an increasingly important role in the healthcare industry, particularly in advanced medical imaging techniques like positron emission tomography-computed tomography (PET-CT) and single photon emission computed tomography (SPECT). An 18/9 MeV cyclotron (18 MeV for proton and 9 MeV for deuteron, Model: Cyclone 18/9, IBA) was installed at the National Institute of Nuclear Medicine and Allied Science (NINMAS), Bangladesh Atomic Energy Commission (BAEC). Radioisotopes such as 18F, 11C, 13N, and 15O can be produced with this cyclotron. Solid target option is also available here which can be used for producing 67Ga, 68Ga, 124I, 123I, 111In, 99mTc, 64Cu, and 89Zr radioisotopes. 18F is the radioisotope of choice for many radiopharmaceuticals due to its glucose analogous and half-life of 110 min. We are producing FDG on a regular basis. For a 60-minute bombardment time, a 40 to 50 micro amp beam current is employed to produce 18F with a mass of 2500 to 3500 mCi. Because of the variable production parameters used, the production of 18F varies. Parameters used in the production of 18F radioisotope are limited to physical factors such as target material, target volume, collimator, stripper foil, and ion source. As a result, we consider 18F yield to be the most important aspect in providing sufficient activity since we want to find the best operating point that minimizes both production time and cost. In order to produce an optimal 18F radioisotope production, all parameters such as dee voltage, vacuum label, beam current, irradiation time, amount of enriched 18O water, target pressure, and others are taken into account. Dhaka Univ. J. Sci. 71(1): 56-59, 2023 (Jan)
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Kauffman, Nathan, James Morrison, Kevin O’Brien, Jinda Fan e Kurt R. Zinn. "Intra-Arterial Delivery of Radiopharmaceuticals in Oncology: Current Trends and the Future of Alpha-Particle Therapeutics". Pharmaceutics 15, n.º 4 (4 de abril de 2023): 1138. http://dx.doi.org/10.3390/pharmaceutics15041138.
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A paradigm shift is underway in cancer diagnosis and therapy using radioactivity-based agents called radiopharmaceuticals. In the new strategy, diagnostic imaging measures the tumor uptake of radioactive agent “X” in a patient’s specific cancer, and if uptake metrics are realized, the patient can be selected for therapy with radioactive agent “Y”. The X and Y represent different radioisotopes that are optimized for each application. X–Y pairs are known as radiotheranostics, with the currently approved route of therapy being intravenous administration. The field is now evaluating the potential of intra-arterial dosing of radiotheranostics. In this manner, a higher initial concentration can be achieved at the cancer site, which could potentially enhance tumor-to-background targeting and lead to improved imaging and therapy. Numerous clinical trials are underway to evaluate these new therapeutic approaches that can be performed via interventional radiology. Of further interest is changing the therapeutic radioisotope that provides radiation therapy by β- emission to radioisotopes that also decay by α-particle emissions. Alpha (α)-particle emissions provide high energy transfer to the tumors and have distinct advantages. This review discusses the current landscape of intra-arterially delivered radiopharmaceuticals and the future of α-particle therapy with short-lived radioisotopes.
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Suhartini, Nita, Barokah Aliyanta e Arief Adhari. "PLANTS COVERING INFLUENCE TO THE RADIOISOTOPES EXISTENCE OF Cs-137 AND Pb-210 IN THE SOIL". Jurnal Forum Nuklir 14, n.º 1 (29 de março de 2020): 7. http://dx.doi.org/10.17146/jfn.2020.14.1.5811.
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PLANTS COVERING INFLUENCE TO THE RADIOISOTOPES EXISTENCE OF 137Cs and 210Pbex IN THE SOIL. Cs-137 and Pbex-210 of environmental radioisotope content in the soil can be useful to estimate the rate of erosion/deposition in an area, by comparing the inventory value of Cs-137 or Pbex-210 in observed site with those in a stable reference site. Cs-137 and Pbex-210 stick very strongly at the surface of the soil (clay), so it can use as a tracer for the movement of soil. Plants very influence the existence of Cs-137 and Pbex-210 environmental radioisotopes as a cover. If without a plant cover, then this environmental radioisotope at the soil would be gone by rain off. This experiment aims to observe the effect of plant cover on the existence of Cs-137 and Pbex-210 at the soil in uncultivated land. Sampling had been done in two uncultivated lands when the land still covering by plants (2016) and after becoming vacant land (2018), using coring (10 cm) for the surface layer and coring (7 cm) for the depth of 20 cm. The result showed that the activity of 137Cs and 210Pbex environmental radioisotopes at the surface layer decreased very significantly, and total inventory values until the depth of 20 cm decreased quite significantly at a vacant land condition. The corrosion rate for the vacant land is higher than the planted land. The value of erosion rate using the 137Cs method is 44.1 t/ha.y (CBG); -4.3t/ha.y (BMC) and 4 t/ha.y (CBG); -27.1 t/ha.y (BMC) for planted land and vacant land, respectively. Meanwhile, using the 210 Pb ex method is -8 t/ha.y (CBG); -36.9 t/ha.y (BMC) for planted land and -58 t/ha.yrs (CBG), -79.9 t/ha.yrs (BMC) for vacant land.
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Birchler, Justin, Courtney Harris, Christopher Sherwood e Tara Kniskern. "Sediment Transport Model Including Short-Lived Radioisotopes: Model Description and Idealized Test Cases". Journal of Marine Science and Engineering 6, n.º 4 (27 de novembro de 2018): 144. http://dx.doi.org/10.3390/jmse6040144.
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Geochronologies derived from sediment cores in coastal locations are often used to infer event bed characteristics such as deposit thicknesses and accumulation rates. Such studies commonly use naturally occurring, short-lived radioisotopes, such as Beryllium-7 (7Be) and Thorium-234 (234Th), to study depositional and post-depositional processes. These radioisotope activities, however, are not generally represented in sediment transport models that characterize coastal flood and storm deposition with grain size patterns and deposit thicknesses. We modified the Community Sediment Transport Modeling System (CSTMS) to account for reactive tracers and used this capability to represent the behavior of these short-lived radioisotopes on the sediment bed. This paper describes the model and presents results from a set of idealized, one-dimensional (vertical) test cases. The model configuration represented fluvial deposition followed by periods of episodic storm resuspension. Sensitivity tests explored the influence on seabed radioisotope profiles by the intensities of bioturbation and wave resuspension and the thickness of fluvial deposits. The intensity of biodiffusion affected the persistence of fluvial event beds as evidenced by 7Be. Both resuspension and biodiffusion increased the modeled seabed inventory of 234Th. A thick fluvial deposit increased the seabed inventory of 7Be and 234Th but mixing over time greatly reduced the difference in inventory of 234Th in fluvial deposits of different thicknesses.
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Braccini, Saverio, e Francisco Alves. "Special Issue ”Instruments and Methods for Cyclotron Produced Radioisotopes”". Instruments 3, n.º 4 (8 de novembro de 2019): 60. http://dx.doi.org/10.3390/instruments3040060.
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The 17th Workshop on Targets and Target Chemistry (WTTC17) was held in Coimbra (Portugal) on 27–31 August 2018. A few months before, the 13th Workshop of the European Cyclotron Network (CYCLEUR) took place in Lisbon (Portugal) on 23–24 November 2017. These two events reassembled major experts in the field of radioisotope production, targets, target chemistry and cyclotrons. In the last few years, significant advances have been obtained in these fields with direct implications for science and society. Instruments and methods, originally developed for nuclear and particle physics, played a crucial role and remarkable developments are on-going. The production of novel radioisotopes for both diagnostics and therapy is expected to produce a breakthrough in nuclear medicine in the next years, paving the way towards theranostics and personalized medicine. This Special Issue presents a collection of original scientific contributions on the latest developments on instruments and methods for medical and research cyclotrons as well as on target and target chemistry for the production of radioisotopes.
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Lima, Carla Flávia de, e Tarcisio Passos Ribeiro de Campo. "Dosimetric evaluation in radiation synovectomy". Brazilian Archives of Biology and Technology 48, spe2 (outubro de 2005): 153–58. http://dx.doi.org/10.1590/s1516-89132005000700022.
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Rheumatoid arthritis can manifest itself through synovitis, of which the knee is the common locale. The treatment using an intra-articular radioisotope injection has been applied in various countries. In this work, the dose of radioactive material absorbed in the joint is evaluated, taking into consideration the dose received in the articular cartilage and adjacencies using a three-dimensional voxel model representing the knee. The radioisotopes studied were Samarium-153 and Dysprosium-165. The results show that the synovial membrane receives 85 to 98% of the normalized dose taken from all voxels representative of the synovium. The following features of 153Sm and of 165Dy - its short physical half-life, the gamma emissions with low energy which allow monitoring the injection trough scintigraphy images, the possibility of binding themselves to macroaggregates that are retained in the joint, the high percentage of the effective dose spread in the synovial membrane - make these suitable radioisotopes for radiation synovectomy.
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KINOSHITA, Fumio. "Application of Radioisotopes to Therapies. I. Overview of radioisotope internal therapy." RADIOISOTOPES 43, n.º 8 (1994): 491–502. http://dx.doi.org/10.3769/radioisotopes.43.8_491.
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Lim, Su Wei, Constantina Chrysochou, David L. Buckley, Philip A. Kalra e Steven P. Sourbron. "Prediction and assessment of responses to renal artery revascularization with dynamic contrast-enhanced magnetic resonance imaging: a pilot study". American Journal of Physiology-Renal Physiology 305, n.º 5 (1 de setembro de 2013): F672—F678. http://dx.doi.org/10.1152/ajprenal.00007.2013.
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The aim of this study was to assess the potential of dynamic contrast-enhanced (DCE) MRI to predict and evaluate functional outcomes after renal artery revascularization for renal artery stenosis (RAS). The single-kidney glomerular filtration rate (SK-GFR) was measured in 15 patients with atherosclerotic RAS with DCE-MRI and radioisotopes at baseline and 4 mo after revascularization. DCE-MRI also produced measurements of blood flow, blood volume, extraction fraction, tubular transit time, and functional volume. Stented kidneys ( n = 22) were divided into three response groups on the basis of the changes in radioisotope SK-GFR: improved ( n = 5), stable ( n = 13), and deteriorated ( n = 4). A good agreement was found between SK-GFR values from DCE-MRI and radioisotopes (correlation coefficient: 0.91). Before intervention, kidneys that improved had lower extraction fraction, higher blood volume, longer tubular transit time, and lower SK-GFR. After intervention, improved kidneys had increased functional volume, and deteriorated kidneys had reduced functional volume and extraction fraction. Revascularization improved blood flow and blood volume in all groups. This pilot study led to the hypothesis that well-vascularized kidneys with reduced extraction fractions are most likely to benefit from revascularization. More generally, DCE-MRI has the potential to replace radioisotope measurement of SK-GFR and may improve patient management by providing additional information on tissue perfusion.
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Hirsch, Ariel E. "Polymethylmethacrylate and Radioisotopes in Vertebral Augmentation: An Explanation of Underlying Principles". September 2009 5;12, n.º 5;9 (14 de setembro de 2009): 887–91. http://dx.doi.org/10.36076/ppj.2009/12/887.
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We recently reported a novel concept for combining radioactive isotope technology with polymethylmethacrylate (PMMA) cement used for vertebral augmentation and have advocated that pain physicians become aware of this new concept when treating malignant compression fractures. The use of vertebral augmentation for malignant compression fractures is steadily increasing, and the goal of this novel approach would be to stabilize the fractured vertebral body while also controlling proliferation of the tumor cells in the vertebral body that caused the vertebral fracture. This approach would therefore provide mechanical stabilization of the fractured vertebral body at the same time as direct targeting of the cancer cells causing the fracture. For our analysis, we investigated six specific radioisotopes with regard to physical and biologic properties as they would interact with PMMA and local bone metastatic disease, taking into consideration anatomical, biological and physical characteristics. The radioisotopes investigated include beta emitting (plus and minus) sources, as well as low energy and mid-energy photon sources and are: P-32, Ho166, Y-90, I-125, F-18, and Tc-99m. We review the advantages and disadvantages of each radioisotope. In addition, this paper serves to provide pain physicians with a basic background of the biologic principles (Biologically Effective Dose) and statistical modeling (Monte Carlo method) used in that analysis. We also review the potential complications when using radioactive sources in a clinical setting. Understanding the methodologies employed in determining isotope selection empowers the practitioner by fostering understanding of this presently theoretical treatment option. We believe that embedding radioisotopes in PMMA is merely a first step in the road of local treatment for symptomatic local lesions in the setting of systemic disease. Key words: polymethylmethacrylate, radioisotopes, vertebral, augmentation, Monte Carlo, biologically, effective, dose
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TANAKA, Eiichi. "Diagnostic imaging by radioisotopes. Basic. IV. Imaging apparatus for radioisotope tomographic diagnosis." RADIOISOTOPES 34, n.º 1 (1985): 57–66. http://dx.doi.org/10.3769/radioisotopes.34.57.
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Salvanou, Evangelia-Alexandra, Argiris Kolokithas-Ntoukas, Christos Liolios, Stavros Xanthopoulos, Maria Paravatou-Petsotas, Charalampos Tsoukalas, Konstantinos Avgoustakis e Penelope Bouziotis. "Preliminary Evaluation of Iron Oxide Nanoparticles Radiolabeled with 68Ga and 177Lu as Potential Theranostic Agents". Nanomaterials 12, n.º 14 (20 de julho de 2022): 2490. http://dx.doi.org/10.3390/nano12142490.
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Theranostic radioisotope pairs such as Gallium-68 (68Ga) for Positron Emission Tomography (PET) and Lutetium-177 (177Lu) for radioisotopic therapy, in conjunction with nanoparticles (NPs), are an emerging field in the treatment of cancer. The present work aims to demonstrate the ability of condensed colloidal nanocrystal clusters (co-CNCs) comprised of iron oxide nanoparticles, coated with alginic acid (MA) and stabilized by a layer of polyethylene glycol (MAPEG) to be directly radiolabeled with 68Ga and its therapeutic analog 177Lu. 68Ga/177Lu- MA and MAPEG were investigated for their in vitro stability. The biocompatibility of the non-radiolabeled nanoparticles, as well as the cytotoxicity of MA, MAPEG, and [177Lu]Lu-MAPEG were assessed on 4T1 cells. Finally, the ex vivo biodistribution of the 68Ga-labeled NPs as well as [177Lu]Lu-MAPEG was investigated in normal mice. Radiolabeling with both radioisotopes took place via a simple and direct labelling method without further purification. Hemocompatibility was verified for both NPs, while MTT studies demonstrated the non-cytotoxic profile of the nanocarriers and the dose-dependent toxicity for [177Lu]Lu-MAPEG. The radiolabeled nanoparticles mainly accumulated in RES organs. Based on our preliminary results, we conclude that MAPEG could be further investigated as a theranostic agent for PET diagnosis and therapy of cancer.
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YAMASHITA, Takashi, e Yoshio ONAI. "Application of Radioisotopes to Therapies. II. Overview of radioisotope external radiotherapy and brachytherapy." RADIOISOTOPES 43, n.º 9 (1994): 565–74. http://dx.doi.org/10.3769/radioisotopes.43.9_565.
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Usman, Rilwan Loko, Umar Ibrahim, Samson Dauda Yusuf, Idris Muhammad Mustapha, Emmanuel Ifeanyi Ugwu e Olatunji Samuel Ayanninuola. "Identification of Medical and Industrial Used Radioisotopes in Mining Sites of Nasarawa, Nasarawa State, Nigeria". Journal of Oncology Research 4, n.º 1 (10 de janeiro de 2022): 27. http://dx.doi.org/10.30564/jor.v4i1.3635.
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This research intends to unveil the presence of radioisotopes in the soil of some mining sites in Nasarawa of Nasarawa state using thermos-scientific interceptor (IdentiFINDER). The work aimed at detecting the presence, types and trust level of radioisotopes. The result showed that, 103Pd and 125I were found in 57% of the total points and the percentage abundance of the detector reached 50-65% indicating that, those radioisotopes are likely found in the area, 109Cd was found in 15% of the total areas. The percentage abundance of the detector for 109Cd shows 50% indicating that, those radioisotopes are likely to be found in the area, 241Am was found in 7% of the total areas. The percentage abundance of the detector for 241Am shows 81% indicating that, those radioisotopes are likely found in the area, 235U was found in 7% of the total points. The percentage abundance of the detector for 235U reaches 57% indicating that, those radioisotopes are likely found in the area, 75Se was found in 7% of the total points. The percentage abundance of the detector for 75Se was in abundance up to 57% indicating that, those radioisotopes are likely gotten in the area and 57Co was gotten in 7% of the total areas. The percentage abundance of the detector for 57Co was 54% indicating that, those radioisotopes are likely to be gotten in the area. Based on this high percentage abundance of the detector for these radioisotopes, they can be harnessed and applied appropriately in medicine and industry.
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Alamaniotis, Miltiadis, Chan K. Choi e Lefteri H. Tsoukalas. "Application of Fireworks Algorithm in Gamma-Ray Spectrum Fitting for Radioisotope Identification". International Journal of Swarm Intelligence Research 6, n.º 2 (abril de 2015): 102–25. http://dx.doi.org/10.4018/ijsir.2015040105.
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Identification of radioisotopic signature patterns in gamma-ray spectra is of paramount importance in various applications of gamma spectroscopy. Therefore, there are several active research efforts to develop accurate and precise methods to perform automated spectroscopic analysis and subsequently recognize gamma-ray signatures. In this work, the authors present a new method for radioisotope identification in gamma-ray spectra obtained with a low resolution radiation detector. The method fits the obtained spectrum with a linear combination of known template signature patterns. Coefficients of the linear combination are evaluated by computing the solution of a single objective optimization problem, whose objective is the Theil-1 inequality coefficient. Optimization of the problem is performed by the Fireworks Algorithm, which identifies a set of coefficients that minimize the Theil-1 value. The computed coefficients are statistically tested for being significantly different than zero or not, and if at least one is found to be zero then the Fireworks Algorithm is used to reiterate fitting using the non-zero templates. Fitting iterations are continued up to the point that no linear coefficients are found to be zero. The output of the method is a list that contains the radioisotopes that have been identified in the measured spectrum. The method is tested on a set of both simulated and real experimental gamma-ray spectra comprised of a variety of isotopes, and compared to a multiple linear regression fitting, and genetic algorithm Theil-1 based fitting. Results demonstrate the potentiality of the Fireworks Algorithm based method, expressed as higher accuracy and similar precision over the other two tested methodologies for radioisotope signature pattern identification in the framework of gamma-ray spectrum fitting.
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Forseth, Torbjørn, Bror Jonsson, Roger Næumann e Ola Ugedal. "Radioisotope Method for Estimating Food Consumption by Brown Trout (Salmo trutta)". Canadian Journal of Fisheries and Aquatic Sciences 49, n.º 7 (1 de julho de 1992): 1328–35. http://dx.doi.org/10.1139/f92-148.
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A fast, simple, and reliable method for estimating food consumption using radioisotopes is presented. The method gives both sensitive short-term and robust long-term estimates of food consumption for brown trout (Salmo trutta). The estimates of daily food rations were similar to those estimated from rates of gastric evacuation and laboratory experiments. The radioisotope method can be used to detect variations in ration size due to temperature, fish size, and food availability. Information on radiocesium absorption from this study and earlier published data on radiocesium retention can be used to estimate daily ration for both piscivorous and benthivorous brown trout. The radioisotope method can be used in radiocesium-contaminated lakes, but it could also be used in other experimental situations by adding stable cesium to small water bodies. The same method is also applicable for use with other stable or radioactive isotopes.
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Maloth, Kotya Naik, Nagalaxmi Velpula, Sridevi Ugrappa e Srikanth Kodangal. "Radioisotopes: An overview". International Journal of Case Reports and Images 5, n.º 9 (2014): 604. http://dx.doi.org/10.5348/ijcri-201457-ra-10012.
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Domínguez-Gadea, Luis, e Laura Cerezo. "Decontamination of radioisotopes". Reports of Practical Oncology & Radiotherapy 16, n.º 4 (julho de 2011): 147–52. http://dx.doi.org/10.1016/j.rpor.2011.05.002.
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Lima, João José Pedroso de. "Radioisotopes in medicine". European Journal of Physics 19, n.º 6 (1 de novembro de 1998): 485–97. http://dx.doi.org/10.1088/0143-0807/19/6/003.
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Krige, John. "Radioisotopes in retrospective". Endeavour 38, n.º 2 (junho de 2014): 68–69. http://dx.doi.org/10.1016/j.endeavour.2014.03.003.
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NOHARA, Norimasa. "Diagnostic imaging by radioisotopes. Basic (VI). Tomographic imaging by radioisotopes." RADIOISOTOPES 34, n.º 3 (1985): 185–93. http://dx.doi.org/10.3769/radioisotopes.34.3_185.
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Pourjafar, Mansoureh. "Radioisotopes in Agricultural Industry". IRA-International Journal of Technology & Engineering (ISSN 2455-4480) 8, n.º 3 (23 de outubro de 2017): 39. http://dx.doi.org/10.21013/jte.v8.n3.p1.
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<p>In environment there are approximately 300 nuclei, containing of different components and their isotopes. Isotopes are nuclei having the similar number of protons and different number of neutrons. Radioisotopes can be applied in vast range of agricultural systems. Scientists are solving the mysteries of multitude agricultural difficulties, which could not have been conceivable with formal ways. Radioisotopes were used in many range of application such as killing insects which damage the food grains by radiations, determining the function of fertilizers in different plants and increase the agricultural produce. Fruits, cereals, canned food and vegetables can be stored for longer periods by moderately exposing them to radiations. Uses of radioisotopes applicable techniques are helping the researchers to find the answer of difficulties in much lesser time. Radioisotopes can be produce from different sources such as nuclear reactors and other atomic installations, and this situation have increased the use of radioisotopes in the agricultural systems. The current paper shortly illustrates the importance of radioisotopes and their radiation in the agricultural areas.</p>
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Pashazadeh, Ali, Nathan Castro, Elena Morganti, Dietmar Hutmacher, Sinja Lagotzki, Axel Boese e Michael Friebe. "Conceptual design of a personalized radiation therapy patch for skin cancer". Current Directions in Biomedical Engineering 4, n.º 1 (1 de setembro de 2018): 607–10. http://dx.doi.org/10.1515/cdbme-2018-0146.
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AbstractRadiation therapy is a valuable option for treatment of skin cancer. In order to deliver the radiation dose to the superficial skin tumor, an X-ray source, electron beam radiation therapy or a radioisotope is applied. The effectiveness of these procedures is well established in the literature. Findings of some recent studies have indicated that beta particles can be of particular interest in suppressing skin tumor growth. Betaemitting radioisotopes are favorable because of the short penetration depth of their emitted particles. Beta radiation can induce significant damage in superficial skin tumor, and at the same time, result in enhanced protection of the underlying healthy tissues. In this study, we propose the design of a patch that can be used in beta radiation therapy of skin cancer patients. For that, we describe the components of this radioactive patch, as well as a proposal for the subsequent clinical application procedure. A scaffold was used as a substrate for embedding the desired beta-emitting radioisotope, and two layers of hydrogel to provide protection and shielding for the radioactively labelled scaffold. The proposed design could provide a universal platform for all beta-emitting radioisotopes. Depending on the depth of the tumor spread, a suitable beta emitter for that specific tumor can be selected and used. This is of particular and critical importance in cases where the tumor is located directly on top of the bone and for which the depth of penetration of radiation should be limited to only the tumor volume. The proposed design has the mechanical flexibility to adapt to curved body regions so as to allow the use in anatomically challenging areas of the body.
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Vi, Chris, Giovanni Mandarano e Sarah Shigdar. "Diagnostics and Therapeutics in Targeting HER2 Breast Cancer: A Novel Approach". International Journal of Molecular Sciences 22, n.º 11 (7 de junho de 2021): 6163. http://dx.doi.org/10.3390/ijms22116163.
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Breast cancer is one of the most commonly occurring cancers in women globally and is the primary cause of cancer mortality in females. BC is highly heterogeneous with various phenotypic expressions. The overexpression of HER2 is responsible for 15–30% of all invasive BC and is strongly associated with malignant behaviours, poor prognosis and decline in overall survival. Molecular imaging offers advantages over conventional imaging modalities, as it provides more sensitive and specific detection of tumours, as these techniques measure the biological and physiological processes at the cellular level to visualise the disease. Early detection and diagnosis of BC is crucial to improving clinical outcomes and prognosis. While HER2-specific antibodies and nanobodies may improve the sensitivity and specificity of molecular imaging, the radioisotope conjugation process may interfere with and may compromise their binding functionalities. Aptamers are single-stranded oligonucleotides capable of targeting biomarkers with remarkable binding specificity and affinity. Aptamers can be functionalised with radioisotopes without compromising target specificity. The attachment of different radioisotopes can determine the aptamer’s functionality in the treatment of HER2(+) BC. Several HER2 aptamers and investigations of them have been described and evaluated in this paper. We also provide recommendations for future studies with HER2 aptamers to target HER2(+) BC.
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Kim, Jinhwan, Kyung Taek Lim, Kilyoung Ko, Eunbie Ko e Gyuseong Cho. "Radioisotope Identification and Nonintrusive Depth Estimation of Localized Low-Level Radioactive Contaminants Using Bayesian Inference". Sensors 20, n.º 1 (23 de dezembro de 2019): 95. http://dx.doi.org/10.3390/s20010095.
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Obtaining the in-depth information of radioactive contaminants is crucial for determining the most cost-effective decommissioning strategy. The main limitations of a burial depth analysis lie in the assumptions that foreknowledge of buried radioisotopes present at the site is always available and that only a single radioisotope is present. We present an advanced depth estimation method using Bayesian inference, which does not rely on those assumptions. Thus, we identified low-level radioactive contaminants buried in a substance and then estimated their depths and activities. To evaluate the performance of the proposed method, several spectra were obtained using a 3 × 3 inch hand-held NaI (Tl) detector exposed to Cs-137, Co-60, Na-22, Am-241, Eu-152, and Eu-154 sources (less than 1μCi) that were buried in a sandbox at depths of up to 15 cm. The experimental results showed that this method is capable of correctly detecting not only a single but also multiple radioisotopes that are buried in sand. Furthermore, it can provide a good approximation of the burial depth and activity of the identified sources in terms of the mean and 95% credible interval in a single measurement. Lastly, we demonstrate that the proposed technique is rarely susceptible to short acquisition time and gain-shift effects.
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Bhagwat, Nikhil M., Manoj D. Chadha, Ameya S. Joshi, Premlata K. Varthakavi, Pradip P. Dalwadi, Bharat R. Sharma, Parimal Tayde, Jagdish A. Chavan e Pratibha T. Pawal. "Not All Low TSH is Graves’ Disease!" An International Journal of Otorhinolaryngology Clinics 6, n.º 1 (2014): 30–34. http://dx.doi.org/10.5005/jp-journals-10003-1147.
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ABSTRACT Thyroid dysfunction is one of the most common endocrine disorders. Low thyroid stimulating hormone (TSH) is not uncommon finding in routine evaluation of thyroid disease. Thyroid imaging with radioisotope is an important modality of investigation to identify different causes of low TSH. In this review article, we have highlighted different causes of low TSH apart from Graves’ disease and how to differentiate among them with the help of thyroid radioisotopes scan. How to cite this article Dalwadi PP, Tayde P, Sharma BR, Chavan JA, Pawal PT, Joshi AS, Chadha MD, Bhagwat NM, Varthakavi PK. Not All Low TSH is Graves’ Disease! Int J Otorhinolaryngol Clin 2014;6(1):30-34.