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Ramos-Mendez JA, Ortiz R, Schuemann J, Paganetti H, Faddegon BA. TOPAS simulation of photo neutrons in radiotherapy: accuracy and speed with variance reduction. Phys Med Biol 2024. [PMID: 38657630 DOI: 10.1088/1361-6560/ad4303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
We provide optimal particle split numbers for speeding up TOPAS Monte Carlo simulations of linear accelerator (linac) treatment heads while maintaining accuracy. In addition, we provide a new TOPAS physics module for simulating photoneutron production and transport.
TOPAS simulation of a Siemens Oncor linac was used to determine the optimal number of splits for directional bremsstrahlung splitting as a function of the field size for 6MV and 18MV x-ray beams. The linac simulation was validated against published data of lateral dose profiles and percentage depth-dose curves (PDD) for the largest square field (40cm side). In separate simulations, neutron particle split and the custom TOPAS physics module was used to generate and transport photoneutrons, called "TsPhotoNeutron". Verification of accuracy was performed by comparing simulations with published measurements of: 1) neutron yields as a function of beam energy for thick targets of Al, Cu, Ta, W, Pb and concrete; and 2) photoneutron energy spectrum at 40cm laterally from the isocenter of the linac from an 18MV beam with closed jaws and MLC.
The optimal number of splits obtained for directional bremsstrahlung splitting enhanced the computational efficiency by two orders of magnitude. The efficiency decreased with increasing beam energy and field size. Calculated lateral profiles in the central region agreed within 1mm/2% from measured data, PDD curves within 1 mm/1%. For the TOPAS physics module, at a split number of 146, the efficiency of computing photoneutron yields was enhanced by a 27.6 factor, whereas it improved the accuracy over existing Geant4 physics modules.
This work provides simulation parameters and a new TOPAS physics module to improve the efficiency and accuracy of TOPAS simulations that involve photonuclear processes occurring in high-Z materials found in linac components, patient devices, and treatment rooms, as well as to explore new therapeutic modalities such as very-high-energy electron therapy.
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Affiliation(s)
- Jose Asuncion Ramos-Mendez
- Department of Oncology Radiation, University of California at San Francisco, 1600 Divisadero Street, Suite HM006, San Francisco, California, 94143-1708, UNITED STATES
| | - Ramon Ortiz
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, San Francisco, CA 94143, USA, San Francisco, California, 94143, UNITED STATES
| | - Jan Schuemann
- Radiation Oncology, Massachusetts General Hospital, Burr Proton Therapy Center, 30 Fruit Street, Boston, Massachusetts, 02114, UNITED STATES
| | - Harald Paganetti
- Northeast Proton Therapy Centre, Massachusetts General Hospital, 30 Fruit Street, Boston, MA 02114, USA, Boston, Massachusetts, 02114, UNITED STATES
| | - Bruce A Faddegon
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, San Francisco, CA 94143, USA, San Francisco, California, 94115, UNITED STATES
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Salvati Manni L, Wood K, Klapproth A, Warr GG. Inelastic neutron scattering and spectroscopy methods to characterize dynamics in colloidal and soft matter systems. Adv Colloid Interface Sci 2024; 326:103135. [PMID: 38520888 DOI: 10.1016/j.cis.2024.103135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 03/25/2024]
Abstract
Colloidal systems and soft materials are well suited to neutron scattering, and the community has readily adopted elastic scattering techniques to investigate their structure. Due to their unique properties, neutrons may also be used to characterize the dynamics of soft materials over a wide range of length and time scales in situ. Both static structures and an understanding of how molecules move about their equilibrium positions is essential if we are to deliver on the promise of rationally designing soft materials. In this review we introduce the basics of neutron spectroscopy and explore the ways in which inelastic neutron scattering can be used to study colloidal and soft materials. Illustrative examples are chosen that highlight the phenomena suitable for investigation using this suite of techniques.
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Affiliation(s)
- Livia Salvati Manni
- School of Chemistry, University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia; School of Chemistry, Monash University, Wellington Road, Clayton, VIC 3800, Australia; School of Environmental and Life Sciences, University of Newcastle, Callaghan 2308, NSW, Australia; Australian Synchrotron, ANSTO, 800 Blackburn Rd, Clayton, VIC 3168, Australia
| | - Kathleen Wood
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Alice Klapproth
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Gregory G Warr
- School of Chemistry, University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia.
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Katubi KM, Alsulami RA, Albarqi MM, Alrowaili ZA, Kebaili I, Singh VP, Al-Buriahi MS. Radiation Shielding efficiency of lead-tungsten-boron glasses with Sb, Al, and Bi against gamma, neutron and charge particles. Appl Radiat Isot 2024; 204:111139. [PMID: 38104471 DOI: 10.1016/j.apradiso.2023.111139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 12/01/2023] [Accepted: 12/02/2023] [Indexed: 12/19/2023]
Abstract
We report on newly developed nuclear shielding glass system based on lead-tungsten-boron (PWB) for radiation applications against photon, neutron and charge particles. This newly developed system contains also different additions, in low concentrations, such as Sb, Al and Bi. The gamma/photon shielding performance was tested by using FLUKA Monte Carlo. Moreover, the shielding efficiency of the present system is examined against charged particles (light and heavy ones) and neutrons. The highest gamma/photons attenuation is observed in the lowest incident energy and this is at the region of the photoelectric absorption. We also observe that the values of effective atomic number (Zeff) show a peak at 100 keV incident energy. The reduction of these values is higher for photon energy range 0.1-1 MeV than below 80 keV energies. The lowest half value layer (d1/2), reflecting the best shielding efficiency, is recorded for the PWB-Bi system. The PWB-Bi system demonstrates promising performance better than many of commercial and standard systems and heavy concretes.
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Affiliation(s)
- Khadijah Mohammedsaleh Katubi
- Department of Chemistry, College of Science, Princess Nourah bint Abdulrahman University, P .O. Box 84428, Riyadh, 11671, Saudi Arabia
| | - Raed A Alsulami
- Nuclear Technologies Institute (NTI), King Abdulaziz City for Science & Technology (KACST), P.O. Box 6086, Riyadh, 11442, Saudi Arabia
| | - Mubarak M Albarqi
- Nuclear Technologies Institute (NTI), King Abdulaziz City for Science & Technology (KACST), P.O. Box 6086, Riyadh, 11442, Saudi Arabia
| | - Z A Alrowaili
- Department of Physics, College of Science, Jouf University, P.O.Box:2014, Sakaka, Saudi Arabia
| | - Imen Kebaili
- Department of Physics, Faculty of Science, King Khalid University, P.O. Box 9004, Abha, Saudi Arabia
| | - V P Singh
- Department of Physics, Karnatak University, Dharwad, 580003, India
| | - M S Al-Buriahi
- Department of Physics, Sakarya University, Sakarya, Turkey
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Yamamoto S, Yoshino M, Nakanishi K, Kamada K, Yoshikawa A, Tanaka H, Kataoka J. Development of an event-by-event based Li-ZnS(Ag) neutron imaging detector with selective neutron detection capability. Appl Radiat Isot 2024; 204:111084. [PMID: 38016258 DOI: 10.1016/j.apradiso.2023.111084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 09/28/2023] [Accepted: 10/23/2023] [Indexed: 11/30/2023]
Abstract
High sensitivity and high resolution is desired in such technologies as neutron radiography. However, the contamination of gamma photons in neutron images decreases the accuracy of neutron radiography. To solve this problem, we developed an event-by-event based neutron imaging system that can selectively detect neutrons. The developed neutron imaging system consists of an Li-ZnS(Ag) scintillator plate optically coupled to a flat panel photomultiplier tube (FP-PMT) with a light guide. Scintillation light emitted from the Li-ZnS(Ag) by the interaction with neutron-induced particles is used to calculate the position based on the center of mass calculations. The spatial resolution of the neutron imaging detector is ∼2.3 mm FWHM, and the sensitivity for 252Cf at 2 cm from the source with 2-cm-thick polystyrene is 20 cps/MBq. Background count fraction from 60Co gamma photons was 0.2 %. For various types of neutron absorption phantoms, high-contrast and high-resolution neutron images are obtained with the developed neutron imaging detector using a252Cf neutron source.
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Affiliation(s)
| | - Masao Yoshino
- New Industry Creation Hatchery Center, Tohoku University, Japan
| | | | - Kei Kamada
- New Industry Creation Hatchery Center, Tohoku University, Japan
| | - Akira Yoshikawa
- New Industry Creation Hatchery Center, Tohoku University, Japan
| | - Hiroki Tanaka
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Japan
| | - Jun Kataoka
- Faculty of Science and Engineering, Waseda University, Japan
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Ward MR, Bull CL, Funnell NP, Warren MR, Oswald IDH. Exploring the effects of high pressure on hydrogen bonding in pharmaceutical cocrystals: A systematic study of pyridine dicarboxylic acid systems using synchrotron and neutron diffraction. Int J Pharm 2023; 647:123514. [PMID: 37844673 DOI: 10.1016/j.ijpharm.2023.123514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 09/19/2023] [Accepted: 10/13/2023] [Indexed: 10/18/2023]
Abstract
Pharmaceutical cocrystals use common robust hydrogen bonding synthons to create novel materials with different physicochemical properties. In this systematic study of a series of cocrystals, we explore the effect of high pressure on one of these commonly used motifs, the acid-pyridine motif, to assess the commonality of behaviour under extreme conditions. We have surveyed five pyridine dicarboxylic acid systems using both synchrotron and neutron diffraction methods to elucidate the changes in structure. We observe that the hydrogen bonding in these systems compress at a similar rate despite the changes to the molecular make-up of the solids and that on compression the changes in structure are indicative that the layers move along the major slip planes in the structure. We have observed two phase transitions to new forms of the pyrazine:malonic acid system, one for each stoichiometric ratio. This study demonstrates that the combination of two complementary diffraction approaches is key to understanding polymorphic behaviour at high pressure.
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Affiliation(s)
- Martin R Ward
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, United Kingdom
| | - Craig L Bull
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxon OX11 0QX, United Kingdom; Department of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom
| | - Nicolas P Funnell
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxon OX11 0QX, United Kingdom
| | - Mark R Warren
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Iain D H Oswald
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, United Kingdom.
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Alver Ü, Duran SU, Demirköz MB, Muçogllava B, Aslan M, Çava K, Özkalaycı F, Dindar O. Ulexite/HDPE-Bi 2O 3/HDPE layered composites for neutron and gamma radiation shielding. Appl Radiat Isot 2023; 200:110940. [PMID: 37453181 DOI: 10.1016/j.apradiso.2023.110940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 06/22/2023] [Accepted: 07/07/2023] [Indexed: 07/18/2023]
Abstract
In this study, 5, 10, and 15 wt% ulexite (NaCaB5O6(ΟH)6·5H2O, hydrated sodium calcium borate hydroxide) and 15 wt %Bi2O3 filled high density polyethylene (HDPE) composite materials were fabricated through conventional melt-extrusion processing techniques in the form of a layered structure in order to absorb both neutron radiations and the secondary radiations resulting from neutron induced reactions. In the layered structure, HDPE was used to slow down neutrons, while ulexite and Bi2O3 were used to capture thermal neutrons and secondary gamma radiations, respectively. The properties of ulexite/HDPE and Bi2O3/HDPE composites were investigated through scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA). The mechanical properties (tensile and hardness) of composite materials were also investigated. The results showed that the addition of ulexite and Bi2O3 particles does not change the thermal and mechanical properties of the HDPE composites significantly. Total macroscopic cross-section of the composites was determined using a 239Pu-Be (α,n) neutron source, while their linear and mass attenuation coefficients were determined using a137Cs gamma-ray source. The results show that ulexite filled HDPE composites enhance neutron shielding property and Bi2O3 filled HDPE composites provide good shielding performance for gamma rays.
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Affiliation(s)
- Ümit Alver
- Karadeniz Technical University, Metallurgical and Materials Engineering, Trabzon, Turkey.
| | - Selcen Uzun Duran
- Program of Medical Imaging Techniques, Vocational School of Health Sciences, Karadeniz Technical University, Trabzon, Turkey
| | - M Bilge Demirköz
- Middle East Technical University, The Research and Application Center for Space and Accelerator Technologies, Ankara, Turkey
| | | | - Mustafa Aslan
- Karadeniz Technical University, Metallurgical and Materials Engineering, Trabzon, Turkey
| | - Kutay Çava
- Karadeniz Technical University, Central Research Laboratory, Trabzon, Turkey
| | - Fatih Özkalaycı
- Karadeniz Technical University, Central Research Laboratory, Trabzon, Turkey
| | - Osman Dindar
- Modedoor Modern Medikal Destek ve Elektronik San. Tic. Ltd. Şti, Ankara, Turkey
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Alsaif NA, Khattari Z, Zakaly HM, Rammah Y, Ene A, Al-Buriahi M. Mechanic-elastic properties and radiation attenuation efficiency of TeO 2/WO 3/K 2O composite glass systems for nuclear and medical application. Heliyon 2023; 9:e18912. [PMID: 37600407 PMCID: PMC10432205 DOI: 10.1016/j.heliyon.2023.e18912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/02/2023] [Accepted: 08/02/2023] [Indexed: 08/22/2023] Open
Abstract
WO3 effects on neutron and ionizing radiation defending factors of ternary tellurite-based glass blocks with molecular formula 80TeO2 -(20-x)WO3 - xK2O; x = 0-20 mol% (denoted as TKW-glass) has been reported via Phy-X theoretical calculations and Geant4 simulation code. Correlations between shielding factors and kinetics properties of the investigated glasses at different photon energy have been examined. The highest values of mass (MAC) attenuation coefficient were noted at 15 keV of the examined TKW-glass materials with the values of 38.408, 44.388, 49.855, 54.872, 59.492 cm2/g for TKW-0, TKW-5, TKW-10, TKW-15, and TKW-20, respectively. Generally, these values of the TKW-glasses obey the sequence: (TKW-0)MAC< (TKW-5)MAC < (TKW-10)MAC < (TKW-15)MAC < (TKW-20)MAC. The highest mean free path (MFP) values of TKW-glasses were registered at 15 MeV with the values of 6.101, 5.591, 5.097, 4.647, and 4.302 cm for TKW-0, TKW-5, TKW-10, TKW-15, and TKW-20, respectively. The two parameters half value layer (HVL) and MFP follow the pattern: (TKW-0)HVL, MFP > (TKW-5)HVL,MFP > (TKW-10)HVL,MFP > (TKW-15)HVL,MFP > (TKW-20)HVL,MFP. The maximum values of effective atomic number (EAN) took place at gamma energy of 15 keV corresponding to 44.35, 48.86, 52.63, 55.83, and 58.58 for TKW-0, TKW-5, TKW-10, TKW-15, and TKW-20, respectively. The trend of the buildup factors was similar for all of the glass specimens. The fast neutron removal cross-section (Σ R ) enhanced as WO3 content increased in the specimens. Thus, the peaked value of Σ R is 0.1059 cm-1 was noted in the TKW-20 sample. Mechanical properties, neutron and γ-rays protection parameters were observed to improve with enhanced WO3 mol% in the TKW-glasses. The current results bear their utilization for neutron and gamma protection purposes.
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Affiliation(s)
- Norah A.M. Alsaif
- Department of Physics, College of Science, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh, 11671, Saudi Arabia
| | - Z.Y. Khattari
- Department of Physics, Faculty of Science, The Hashemite University, P. O. Box 330127, Zarqa, 13133, Jordan
| | - Hesham M.H. Zakaly
- Institute of Physics and Technology, Ural Federal University, 620002, Ekaterinburg, Russia
- Istinye University, Faculty of Engineering and Natural Sciences, Computer Engineering Department, Istanbul 34396, Turkey
- Physics Department, Faculty of Science, Al-Azhar University, Assiut, 71524, Egypt
| | - Y.S. Rammah
- Physics Department, Faculty of Science, Menoufia University, 32511, Shebin El Koom, Egypt
| | - Antoaneta Ene
- INPOLDE Research Center, Department of Chemistry, Physics and Environment, Faculty of Sciences and Environment, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008, Galati, Romania
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Alzahrani JS, Alrowaili ZA, Alqahtani MS, Adam M, Olarinoye IO, Durmaz U, Al-Buriahi MS. Neutron attenuation features and elastic properties of silicate glasses containing Ta 2O 5, and Li 2O. Appl Radiat Isot 2023; 199:110896. [PMID: 37311298 DOI: 10.1016/j.apradiso.2023.110896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 06/03/2023] [Accepted: 06/05/2023] [Indexed: 06/15/2023]
Abstract
In this investigation, the elastic properties and neutrons attenuation factors for some optical glasses containing Ta2O5, SiO2, and Li2O were reported. The present glasses were also consisted of ZrO2 and Nb2O5 in very small concentrations. The glasses are chemically defined as 26.47Li2O-5.88ZrO2-(20-x)Ta2O5-xNb2O5-47.06SiO2, where, x takes the values: 0, 2.94, 5.88, and 11.77 mol%. The elastic properties of these glassy specimens were determined by employing Makishima-Mackenzie's theory (M.M.T). By using the same method, moreover, the micro-hardness and Poisson's ratio were assessed. Cross sections for slow, moderated, and fissile neutrons were computed through standard expressions and models. In addition, the influence of the partial replacement of Ta2O5 by Nb2O5 on the parameters were also analysed. The glass with the lowest Nb2O5 content presented the highest cross sections for fast, moderated, and slow neutrons. The neutron-absorption ability of included glasses declined as glass density declined and Nb2O5 molar concentration increased in the glasses. Therefore, the sample with the highest Ta2O5 content is recommended for neutron absorption applications.
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Affiliation(s)
- Jamila S Alzahrani
- Department of Physics, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh, 11671, Saudi Arabia
| | - Z A Alrowaili
- Department of Physics, College of Science, Jouf University, P.O.Box:2014, Sakaka, Saudi Arabia
| | - Mohammed S Alqahtani
- Department of Radiological Sciences, College of Applied Medical Sciences, King Khalid University, Abha, 61421, Saudi Arabia
| | - Mohamed Adam
- Department of Radiological Sciences, College of Applied Medical Sciences, King Khalid University, Abha, 61421, Saudi Arabia
| | - I O Olarinoye
- Department of Physics, School of Physical Sciences, Federal University of Technology, Minna, Nigeria
| | - Ufuk Durmaz
- Department of Mechanical Engineering, Engineering Faculty, Sakarya University, Sakarya, Turkey
| | - M S Al-Buriahi
- Department of Physics, Sakarya University, Sakarya, Turkey.
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Kinashi Y, Takata T, Sakurai Y, Tanaka H. Carcinogenesis Observed in the Spleens of Balb/c Mice After Head- neutron Irradiation. Anticancer Res 2023; 43:1455-1461. [PMID: 36974803 DOI: 10.21873/anticanres.16294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 03/29/2023]
Abstract
BACKGROUND/AIM To investigate the long-term influence of head-neutron irradiation on mice spleens, post-radiation late effects were examined in three types of mice: Balb/c and severe combined immunodeficiency (SCID) mice, which have high radio-sensitivities, and C3H mice. MATERIALS AND METHODS Neutron irradiation was performed with the neutron beam of the Kyoto University Research Reactor. Survival fractions and the change in spleen size after head-neutron irradiation were investigated in three different types of mice. Physical condition after neutron irradiation was observed for eighteen months. RESULTS The onset of primary splenic malignant lymphoma was recognized in many of the Balb/c mice 18 months after head-neutron irradiation. Eight months after head-neutron irradiation, many SCID mice developed an abscess in the part exposed to radiation and spleen swelling. The swollen spleen of SCID mice had hematopoiesis from the marrow. CONCLUSION Low energy head-neutron irradiation damages immune organs in radiosensitive SCID and Balb/c mice. A combination of boron neutron capture therapy and immunotherapy may be less toxic than low-energy neutron-irradiation alone.
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Affiliation(s)
- Yuko Kinashi
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Takushi Takata
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Yoshinori Sakurai
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Hiroki Tanaka
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
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Rondelli V, Koutsioubas A, Di Cola E, Fragneto G, Grillo I, Del Favero E, Colombo L, Cantù L, Brocca P, Salmona M. Dysmyelination and glycolipid interference caused by phenylalanine in phenylketonuria. Int J Biol Macromol 2022; 221:784-95. [PMID: 36099998 DOI: 10.1016/j.ijbiomac.2022.09.062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 09/07/2022] [Accepted: 09/07/2022] [Indexed: 11/20/2022]
Abstract
Phenylketonuria (PKU) is a metabolic disorder connected to an excess of phenylalanine (Phe) in the blood and tissues, with neurological consequences. The disease's molecular bases seem to be related to the accumulation of Phe at the cell membrane surface. Radiological outcomes in the brain demonstrate decreased water diffusivity in white matter, involving axon dysmyelination of not yet understood origin. We used a biophysical approach and model membranes to extend our knowledge of Phe-membrane interaction by clarifying Phe's propensity to affect membrane structure and dynamics based on lipid composition, with emphasis on modulating cholesterol and glycolipid components to mimic raft domains and myelin sheath membranes. Phe showed affinity for the investigated membrane mimics, mainly affecting the Phe-facing membrane leaflet. The surfaces of our neuronal membrane raft mimics were strong anchoring sites for Phe, showing rigidifying effects. From a therapeutic perspective, we further investigated the role of doxycycline, known to disturb Phe packing, unveiling its action as a competitor in Phe interactions with the membrane, suggesting its potential for treatment in the early stages of PKU. Our results suggest how Phe accumulation in extracellular fluids can impede normal growth of myelin sheaths by interfering with membrane slipping and by remodulating free water and myelin-associated water contents.
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11
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Ismail SS, Sani SFA, Khandaker MU, Tamchek N, Karim JA, Almugren KS, Alkallas FH, Shafiqah ASS, Bradley DA. Dosimetric characteristics of Gd-doped silica glass subjected to neutron and gamma irradiations. Appl Radiat Isot 2022; 189:110409. [PMID: 36037726 DOI: 10.1016/j.apradiso.2022.110409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 08/01/2022] [Accepted: 08/04/2022] [Indexed: 11/19/2022]
Abstract
The dosimetric characteristics of newly developed gadolinium (Gd) glass dosimeter produced via sol-gel method are reported. Irradiation were made using a 750 kW neutron flux thermal power and 1.25 MeV 60Co gamma rays with entrance doses from 2 to 10 Gy. Investigation has been done on various Gd dopant concentrations, ranging from 1 to 10 mol%. The Gd-doped silica glass have been characterised for thermoluminescence (TL) dose response, sensitivity, linearity index, glow curve and kinetic parameter analysis. For particular dopant concentration obtained in 6 mol% Gd, the least squares fit shows the change in TL yield, correlation coefficient (r2) of better than 0.980 (at 95% confidence level), with neutron and gamma exposure to be 8 and 4 times greater than that of 1 mol% Gd, respectively. Broad peaks in the absence of any sharp peak observed in the glow curve confirms the amorphous nature of the prepared glass. A glow curve of Gd-doped SiO2 sample is observed with a single prominent peak (Tm) within 200-250 °C (peak shifting appears with respect to the increment of dopant concentration) and 350 °C (for all respective Gd dopants) for neutron and gamma irradiations, respectively. Deconvolution shows the glow curves of the Gd-doped SiO2 glass to be formed of seven and five overlapping peaks, with figures of merit below 2% (FOM) of between 1.38-1.79 and 1.30-1.97 for the particular neutron and gamma irradiations, respectively. Through use of Glowfit deconvolution software, the key trapping parameters of activation energy, E and frequency factor, s-1 were calculated for the Gd-doped SiO2 glass. The mechanism of TL yield with the gradual increase in Gd concentrations and doses is explained upon the incorporation of Gd and radiation damage that change the structure of the electron traps in the glass matrix. These early results indicate that selectively screened Gd-SiO2 glass can be developed into a promising TL system towards dosimetric applications.
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Affiliation(s)
- S S Ismail
- Centre for Applied Physics and Radiation Technologies, School of Medical and Life Science, 47500, Bandar Sunway, Selangor, Malaysia.
| | - S F Abdul Sani
- Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - M U Khandaker
- Centre for Applied Physics and Radiation Technologies, School of Medical and Life Science, 47500, Bandar Sunway, Selangor, Malaysia; Department of General Educational Deveopment, Faculty of science and Information Technology, Daffodil International University, DIU Rd, Dhaka 1341, Bangladesh
| | - N Tamchek
- Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Julia A Karim
- Nuclear and Reactor Physics Section, Nuclear Technology Center, Technical Support Division, Malaysian Nuclear Agency, Kajang, Malaysia
| | - K S Almugren
- Department of Physics, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - F H Alkallas
- Department of Physics, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - A S Siti Shafiqah
- Dept of Physics, Kuliyyah of Science, International Islamic University Malaysia, 25200, Kuantan, Malaysia
| | - D A Bradley
- Centre for Applied Physics and Radiation Technologies, School of Medical and Life Science, 47500, Bandar Sunway, Selangor, Malaysia; Department of Physics, University of Surrey, Guildford, GU2 7XH, UK
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12
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Ghavami A, Tajik M. Design of an on-line monitoring system based on a 3He detector. Appl Radiat Isot 2022; 188:110366. [PMID: 35839711 DOI: 10.1016/j.apradiso.2022.110366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 06/20/2022] [Accepted: 07/05/2022] [Indexed: 11/20/2022]
Abstract
In this study, a neutron monitoring system based on a cylindrical 3He detector was designed and simulated using MCNPX code for the nuclear laboratories that use neutron sources for educational and research purposes. According to the simulation results, the monitoring system was experimentally tested with different moderators. Finally, using experimental and simulation results, a monitoring system with appropriate efficiency was built based on the considered detector and, its efficiency was measured in different conditions. The test results show that this system can measure the background radiation of the laboratory environment efficiently.
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Affiliation(s)
- Ahad Ghavami
- School of Physics, Damghan University, P.O. Box 36716-41167, Damghan, Iran
| | - Mojtaba Tajik
- School of Physics, Damghan University, P.O. Box 36716-41167, Damghan, Iran.
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13
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Kim HS, Kwon HJ, Kim KY, Lee JS, Kim Y. Operational status of and upgrade plan for the 100-MeV proton linac at the Korea multi-purpose accelerator complex. J Korean Phys Soc 2022; 80:799-807. [PMID: 35125629 PMCID: PMC8804671 DOI: 10.1007/s40042-022-00396-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 11/15/2021] [Accepted: 11/15/2021] [Indexed: 06/14/2023]
Abstract
The report presents the operation status of and upgrade plan for the 100-MeV proton linac at the Korea Multi-purpose Accelerator Complex (KOMAC). First, an operation history of the 100-MeV linac since its commissioning in 2013, such as operation hours, user services, machine availabilities, and downtimes, is discussed. Second, the status of the beamlines in service or under development is described in a detailed manner. Finally, the Korea Spallation Neutron Source (KSNS), which is part of the upgrade plan for the 100-MeV proton linac to expand its utilization fields, is discussed.
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Affiliation(s)
- Han-Sung Kim
- Korea Multi-Purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju, Gyeongbuk-do 38180 Republic of Korea
| | - Hyeok-Jung Kwon
- Korea Multi-Purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju, Gyeongbuk-do 38180 Republic of Korea
| | - Kui-Young Kim
- Korea Multi-Purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju, Gyeongbuk-do 38180 Republic of Korea
| | - Jae-Sang Lee
- Korea Multi-Purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju, Gyeongbuk-do 38180 Republic of Korea
| | - Yujong Kim
- Korea Multi-Purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju, Gyeongbuk-do 38180 Republic of Korea
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14
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Takada M, Nunomiya T, Masuda A, Matsumoto T, Tanaka H, Nakamura S, Endo S, Nakamura M, Aoyama K, Ueda O, Narita M, Nakamura T. Development of a real-time neutron beam detector for boron neutron capture therapy using a thin silicon sensor. Appl Radiat Isot 2021; 176:109856. [PMID: 34273618 DOI: 10.1016/j.apradiso.2021.109856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 10/20/2022]
Abstract
We have developed a new real-time neutron detector, which is able to measure a direct neutron beam of boron neutron capture therapy. The detector consists of both a 40-μm-thick pn diode and around 0.09-μm-thick LiF neutron converter. Experimental results indicate that this neutron detector can measure neutron flux up to 1 × 109 (cm-2 s-1), separately from gamma rays around 500 mGy/h. The measured depth distribution of neutron flux in an acrylic block is in agreement with the activation results of gold.
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Affiliation(s)
- Masashi Takada
- Department of Applied Physics, National Defense Academy of Japan, 1-10-20 Hashirimizu, Yokosuka, Kanagawa 239-8686, Japan.
| | - Tomoya Nunomiya
- Fuji Electric Co. Ltd, 1 Fuji-machi, Hino, Tokyo 191-8502, Japan
| | - Akihiko Masuda
- National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - Tetsuro Matsumoto
- National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - Hiroki Tanaka
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2 Asashiro-Nishi Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Satoshi Nakamura
- Department of Medical Physics, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Satoru Endo
- Quantum Energy Applications, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527, Japan
| | - Masaru Nakamura
- Cancer Intelligence Care Systems Inc., 3-5-7 Ariake, Koto-ku, Tokyo 135-0063, Japan
| | - Kei Aoyama
- Fuji Electric Co. Ltd, 1 Fuji-machi, Hino, Tokyo 191-8502, Japan
| | - Osamu Ueda
- Fuji Electric Co. Ltd, 1 Fuji-machi, Hino, Tokyo 191-8502, Japan
| | - Masataka Narita
- Fuji Electric Co. Ltd, 1 Fuji-machi, Hino, Tokyo 191-8502, Japan
| | - Takashi Nakamura
- Fuji Electric Co. Ltd, 1 Fuji-machi, Hino, Tokyo 191-8502, Japan; Cyclotron and Radioisotope Center, Tohoku University, Aoba Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
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15
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El Amri L, Chetaine A, Amsil H, Jalil A, El Mokhtari B, Embarch K, Benchrif A, Laraki K, Marah H. Neutron guide optimization for the Moroccan PGAA system. Appl Radiat Isot 2021; 174:109783. [PMID: 34058521 DOI: 10.1016/j.apradiso.2021.109783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 04/14/2021] [Accepted: 05/14/2021] [Indexed: 11/21/2022]
Abstract
The Moroccan TRIGA Mark II research reactor is to be equipped with a PGAA (Prompt Gamma Activation Analysis) facility to assist the country's progression in socioeconomic areas such as the environment and geochemistry, agriculture, health, industry, cultural heritage, and human sciences. The requirements of the PGAA facility include a very high thermal to fast neutron flux ratio and a focused, thin beam. Supermirror neutron guides are generally used to meet such requirements due to their ability to reflect neutrons with a specific energy and scattering angle. This study was undertaken to determine a suitable neutron guide for achieving optimal performance for the PGAA facility, where such a determination needs to be made according to both the available space and the minimum performance needed for PGAA analysis. To better parameterize the neutron guide, a set of simulations were performed with the aim of establishing the best guide specifications. Three types of neutron guides were studied, namely straight, curved, and bender. McStas code was used in this study, and the simulations showed that the guides must be 6 m long and that the coating value m must be equal to 5 for the bender and straight guides and 6 for the curved guide. Among the three guide types, the thermal/epithermal (Фth/Фep) and thermal/fast (Фth/Фfast) ratios were found to be much better when using the curved guide.
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16
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Moriyama H, Daino K, Ishikawa A, Imaoka T, Nishimura M, Nishimura Y, Takabatake M, Morioka T, Inoue K, Fukushi M, Shimada Y, Kakinuma S. Exome of Radiation-induced Rat Mammary Carcinoma Shows Copy-number Losses and Mutations in Human-relevant Cancer Genes. Anticancer Res 2021; 41:55-70. [PMID: 33419799 DOI: 10.21873/anticanres.14751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 11/14/2020] [Indexed: 11/10/2022]
Abstract
BACKGROUND/AIM Our understanding of cancer risk from neutron exposure is limited. We aimed to reveal the characteristics of mammary carcinomas induced by neutrons. MATERIALS AND METHODS Mammary carcinomas obtained from female Sprague-Dawley rats irradiated at 7 weeks of age with 0.97 Gy neutrons or 4 Gy γ-rays and from non-irradiated rats were classified into luminal and non-luminal subtypes by immunohistochemistry. Their mutational landscapes were determined by whole-exome sequencing. RESULTS Neutrons significantly raised the incidence of luminal mammary carcinomas over the non-luminal subtype. Somatic mutations were identified in cancer genes involved in several signalling pathways, including Keap1/Nrf2, Pi3k/Akt and Wnt/β-catenin. Focal copy-number losses involving cancer genes were observed mainly in carcinomas from the irradiated rats. CONCLUSION Neutrons increase the incidence of luminal mammary carcinomas, probably through gene mutations similar to those found in human breast cancers, and focal copy-number losses including cancer genes that are characteristics of radiation-induced mammary carcinomas.
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Affiliation(s)
- Hitomi Moriyama
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan.,Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan.,Present address: Konica Minolta, Inc., Tokyo, Japan
| | - Kazuhiro Daino
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan;
| | - Atsuko Ishikawa
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
| | - Tatsuhiko Imaoka
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan.,Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - Mayumi Nishimura
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
| | - Yukiko Nishimura
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan.,Present address: Institute for Environmental Sciences, Aomori, Japan
| | - Masaru Takabatake
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan.,Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan.,Present address: Georgetown University, Washington, DC, U.S.A
| | - Takamitsu Morioka
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
| | - Kazumasa Inoue
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - Masahiro Fukushi
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - Yoshiya Shimada
- Present address: Institute for Environmental Sciences, Aomori, Japan.,Executive Director, QST, Chiba, Japan
| | - Shizuko Kakinuma
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan.,Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
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17
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Wimley WC. How We Came to Understand the "Tumultuous Chemical Heterogeneity" of the Lipid Bilayer Membrane. J Membr Biol 2020; 253:185-90. [PMID: 32488366 DOI: 10.1007/s00232-020-00126-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 05/29/2020] [Indexed: 10/24/2022]
Abstract
The path to our modern understanding of the structure of the lipid bilayer membrane is a long one that can be traced from today perhaps as far back as Benjamin Franklin in the eighteenth century. Here, I provide a personal account of one of the important steps in that path, the description of the "Complete Structure" of a hydrated, fluid phase dioleoyl phosphatidylcholine bilayer by the joint refinement of neutron and X-ray diffraction data by Stephen White and his colleagues.
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18
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Afkham Y, Mesbahi A, Alemi A, Zolfagharpour F, Jabbari N. Design and fabrication of a Nano-based neutron shield for fast neutrons from medical linear accelerators in radiation therapy. Radiat Oncol 2020; 15:105. [PMID: 32393290 PMCID: PMC7216519 DOI: 10.1186/s13014-020-01551-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 04/27/2020] [Indexed: 11/24/2022] Open
Abstract
Background Photo-neutrons are produced at the head of the medical linear accelerators (linac) by the interaction of high-energy photons, and patients receive a whole-body-absorbed dose from these neutrons. The current study aimed to find an efficient shielding material for fast neutrons. Methods Nanoparticles (NPs) of Fe3O4 and B4C were applied in a matrix of silicone resin to design a proper shield against fast neutrons produced by the 18 MeV photon beam of a Varian 2100 C/D linac. Neutron macroscopic cross-sections for three types of samples were calculated by the Monte Carlo (MC) method and experimentally measured for neutrons of an Am-Be source. The designed shields in different concentrations were tested by MCNPX MC code, and the proper concentration was chosen for the experimental test. A shield was designed with two layers, including nano-iron oxide and a layer of nano-boron carbide for eliminating fast neutrons. Results MC simulation results with uncertainty less than 1% showed that for discrete energies and 50% nanomaterial concentration, the macroscopic cross-sections for iron oxide and boron carbide at the energy of 1 MeV were 0.36 cm− 1 and 0.32 cm− 1, respectively. For 30% nanomaterial concentration, the calculated macroscopic cross-sections for iron oxide and boron carbide shields for Am-Be spectrum equaled 0.12 cm− 1 and 0.15 cm− 1, respectively, while they are 0.15 cm− 1 and 0.18 cm− 1 for the linac spectrum. In the experiment with the Am-Be spectrum, the macroscopic cross-sections for 30% nanomaterial concentration were 0.17 ± 0.01 cm− 1 for iron oxide and 0.21 ± 0.02 cm− 1 for boron carbide. The measured transmission factors for 30% nanomaterial concentration with the Am-Be spectrum were 0.71 ± 0.01, 0.66 ± 0.02, and 0.62 ± 0.01 for the iron oxide, boron carbide, and double-layer shields, respectively. In addition, these values were 0.74, 0.69, and 0.67, respectively, for MC simulation for the linac spectrum at the same concentration and thickness of 2 cm. Conclusion Results achieved from MC simulation and experimental tests were in a satisfactory agreement. The difference between MC and measurements was in the range of 10%. Our results demonstrated that the designed double-layer shield has a superior macroscopic cross-section compared with two single-layer nanoshields and more efficiently eliminates fast photo-neutrons.
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Affiliation(s)
- Younes Afkham
- Department of Medical Physics, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran
| | - Asghar Mesbahi
- Molecular Medicine Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Abdolali Alemi
- Department of Inorganic Chemistry, Faculty of chemistry, Tabriz University, Tabriz, Iran
| | - Farhad Zolfagharpour
- Department of Physics, Faculty of Basic Sciences, University Of Mohaghegh Ardebili, Ardabil, Iran
| | - Nasrollah Jabbari
- Solid Tumor Research Center, Cellular and Molecular Medicine Institute, Urmia University of Medical Sciences, Urmia, Iran.
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19
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Kinashi Y, Ikawa T, Takahashi S. The combined effect of neutron irradiation and temozolomide on glioblastoma cell lines with different MGMT and P53 status. Appl Radiat Isot 2020; 163:109204. [PMID: 32561044 DOI: 10.1016/j.apradiso.2020.109204] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 12/20/2019] [Accepted: 04/10/2020] [Indexed: 11/21/2022]
Abstract
Temozolomide (TMZ) is a DNA-alkylating agent used for chemo-radiotherapy of glioblastoma, which is also a target cancer for boron neutron capture therapy (BNCT). Although the DNA-repair enzyme O6-methylguanine DNA methyltransferase (MGMT) and the tumor suppressor p53 are mutated in some glioblastoma cells, it remains unknown whether these mutations affect sensitivity to neutron irradiation. We examined sensitivity to neutron irradiation and TMZ in two glioblastoma cell lines: T98G, which is p53-mutant with high levels of MGMT activity; and A172, which is p53-wild-type and has low MGMT activity. T98G cells were more resistant to TMZ treatment than A172 cells, with a 10-fold higher LC50. In A172 cells, TMZ treatment did not change the cell-killing effect of neutron irradiation in the presence of borono-phenylalanine (BPA). By contrast, T98G cells were more resistant to neutron irradiation when BPA was present. These results indicate that DNA repair activity in T98G cells might be higher due to upregulation of MGMT after TMZ treatment. Thus, differences in the MGMT and p53 statuses of glioblastoma cells might predict the effect of combination therapy with BNCT and DNA-alkylating agent.
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20
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Baltazar-Raigosa A, Soto-Bernal TG, Vega-Carrillo HR, Garcia-Duran A, Torres-Cortes CO, Galvan-Tejada JI, Gamboa-Rosales H. CubBonner - A novel passive neutron area monitor. Appl Radiat Isot 2020; 161:109129. [PMID: 32250840 DOI: 10.1016/j.apradiso.2020.109129] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/25/2020] [Accepted: 03/12/2020] [Indexed: 11/23/2022]
Abstract
Responses of a novel passive neutron area monitor, named CubBonner, were calculated. The responses were estimated for sixty monoenergetic neutrons, from 10-9 to 20 MeV, with the MCNP5 code. The CubBonner is a cubic polyethylene moderator and a gold foil as thermal neutron detector. The ambient dose equivalent response was calculated for three cubes (5″, 8″ and 10" side) with the gold foil at the cube's centers. The moderator cube having the best ambient dose equivalent response was used to estimate the neutron fluence and the 197Au(n,γ) responses per history. The ambient dose response per unit mass of gold was compared with the response of the Berthold LB 6411 active neutron area monitor, and the response for the (n,γ) reaction in the gold foil was compared with the evaporation photo neutrons produced in linear accelerators for radiotherapy.
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Ghasemi-Jangjoo A, Ghiasi H. Application of the phase-space distribution approach of Monte Carlo for radiation contamination dose estimation from the (n,γ), (γ,n) nuclear reactions and linac leakage photons in the megavoltage radiotherapy facility. Rep Pract Oncol Radiother 2020; 25:233-240. [PMID: 32025221 DOI: 10.1016/j.rpor.2020.01.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 12/24/2019] [Accepted: 01/20/2020] [Indexed: 11/18/2022] Open
Abstract
Aim The aim of this study was to characterize the radiation contamination inside and outside the megavoltage radiotherapy room. Background Radiation contamination components in the 18 MV linac room are the secondary neutron, prompt gamma ray, electron and linac leakage radiation. Materials and Methods An 18 MV linac modeled in a typical bunker employing the MCNPX code of Monte Carlo. For fast calculation, phase-space distribution (PSD) file modeling was applied and the calculations were conducted for the radiation contamination components dose and spectra at 6 locations inside and outside the bunker. Results The results showed that the difference of measured and calculated percent depth-dose (PDD) and photo beam-profile (PBP) datasets were lower than acceptable values. At isocenter, the obtained photon dose and neutron fluence were 2.4 × 10-14 Gy/initial e° and 2.22 × 10-8 n°/cm2, respectively. Then, neutron apparent source strength (QN) value was found as 1.34 × 1012 n°/Gy X at isocenter and the model verified to photon and neutron calculations. A surface at 2 cm below the flattening filter was modeled as phase-space (PS) file for PDD and PBP calculations. Then by use of a spherical cell in the center of the linac target as a PS surface, contaminant radiations dose, fluence and spectra were estimated at 6 locations in a considerably short time, using the registered history of all particles and photons in the 13GB PSD file as primary source in the second step. Conclusion Designing the PSD file in MC modeling helps user to solve the problems with complex geometry and physics precisely in a shorter run-time.
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Affiliation(s)
- Amir Ghasemi-Jangjoo
- Medical Radiation Sciences Research Team, Imam Hospital, Tabriz University of Medical Sciences, Imam Hospital, Tabriz, Iran
- Department of Radiology and Radiotherapy, Medicine School, Tabriz University of Medical Sciences, Imam Hospital, Tabriz, Iran
| | - Hosein Ghiasi
- Medical Radiation Sciences Research Team, Imam Hospital, Tabriz University of Medical Sciences, Imam Hospital, Tabriz, Iran
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Abstract
IMAGINE is a high intensity, quasi-Laue neutron crystallography beamline developed at the 85MW High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). This state-of-the-art facility for neutron-diffraction enables neutron protein structures to be determined at or near atomic resolutions from crystals with volumes of <1mm3 and unit cell edges of <150Å. The beamline features include elliptical focusing mirrors that deliver neutrons into a 2.0×3.2mm2 focal spot at the sample position, and variable short and long wavelength cutoff optics that provide automated exchange between multiple wavelength configurations. The beamline is equipped with a single-axis goniometer, neutron-sensitive cylindrical image plate detector and room temperature and cryogenic sample environments. This article describes the beamline components, the diffractometer and the data collection and data analysis protocols that are used, and outlines the protein deuteration, crystallization and conventional crystallography capabilities that are available to users at ORNL's neutron facilities. We also present examples of the scientific questions being addressed at this beamline and highlight important findings in enzyme chemistry that have been made possible by IMAGINE.
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Affiliation(s)
- Flora Meilleur
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States; Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, United States.
| | - Andrey Kovalevsky
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Dean A A Myles
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
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23
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Bhayani D, Naik H, Nathaniel TN, Khan S, Mehta P. Simulated space radiation: Investigating ionizing radiation effects on the stability of amlodipine besylate API and tablets. Eur J Pharm Sci 2019; 137:104982. [PMID: 31276739 DOI: 10.1016/j.ejps.2019.104982] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 05/06/2019] [Accepted: 06/30/2019] [Indexed: 11/26/2022]
Abstract
Efficacious pharmaceuticals with the adequate shelf life are essential for the well-being of the space explorers and successful completion of a space mission. Space is brimming with different types of radiations, which penetrate inside the spacecraft despite the shielding material. Such radiations can alter the stability of the pharmaceuticals during long duration space missions. The literature reporting the space radiation effects on the pharmaceuticals is scarce in a public domain. Ground-based simulation studies can be useful to predict the influence of the space radiations on the stability of the pharmaceuticals. Based upon these facts, the main objective of the present preliminary work was to investigate the effect of different types of ionizing radiations on the stability of amlodipine besylate API and tablets. Amlodipine besylate samples were irradiated by protons, neutrons (thermal and fast), gamma and heavy ion (56Fe) radiations with their different doses. The samples were also irradiated with UV-visible radiation to compare the effect of selected ionizing radiations with photodegradation. The physical stability was examined through organoleptic evaluation and the chemical stability was evaluated by FTIR and HPLC. The results of the organoleptic evaluation showed colour changes from colourless to yellow in proton irradiated solid API and gamma irradiated API aqueous solution. The FTIR spectrum of proton irradiated API showed one additional absorption band at 1728 cm-1 due to degradation products. HPLC analysis revealed that amlodipine degraded up to 10% and 21% after the highest doses of proton and gamma irradiation, respectively. No physical or chemical changes were observed after neutron and 56Fe irradiation. The structures of major radiolytic products were elucidated using LC-MS/MS. Two new impurities were found in the API aqueous solution as a result of gamma irradiation. The drug degradation pathways were postulated by proposing the plausible mechanism of formation.
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Affiliation(s)
- Dhara Bhayani
- Institute of Pharmacy, Nirma University, Ahmedabad, Gujarat 382481, India
| | - Haladhara Naik
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - T Newton Nathaniel
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Saif Khan
- Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Priti Mehta
- Institute of Pharmacy, Nirma University, Ahmedabad, Gujarat 382481, India.
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Alrwashdeh M, Alameri S. Evaluation review of the 250Cf neutron cross section. Appl Radiat Isot 2019; 154:108869. [PMID: 31445490 DOI: 10.1016/j.apradiso.2019.108869] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/11/2019] [Accepted: 08/15/2019] [Indexed: 10/26/2022]
Abstract
This research investigated the data for the cross section of the 250Cf isotope in the unresolved resonance region, where the incident particle with a specific energy is either neutral or charged. Both the angular distribution and the differential cross sections of 250Cf were evaluated in the specific energy range. In this research, the Reich-Moore R-matrix approximation was used to evaluate the theoretical cross section, and sophisticated models were employed to evaluate and describe the background experimental data by including the reduction parameters for the experimental data. The evaluated resonance integral-capture cross section and thermal resonance integral-capture cross section showed a good agreement with the tabulated values found in the literature on the unresolved resonance energy region for 250Cf in the range from 0.01 meV to 20 meV.
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Affiliation(s)
- Mohammad Alrwashdeh
- Department of Nuclear Engineering, Khalifa University of Science and Technology, PO Box 127788, Abu Dhabi, United Arab Emirates.
| | - Saeed Alameri
- Department of Nuclear Engineering, Khalifa University of Science and Technology, PO Box 127788, Abu Dhabi, United Arab Emirates
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Moriyama H, Daino K, Imaoka T, Nishimura M, Nishimura Y, Takabatake M, Morioka T, Fukushi M, Shimada Y, Kakinuma S. Neutron-induced Rat Mammary Carcinomas Are Mainly of Luminal Subtype and Have Multiple Copy Number Aberrations. Anticancer Res 2019; 39:1135-1142. [PMID: 30842142 DOI: 10.21873/anticanres.13222] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 01/25/2019] [Accepted: 02/01/2019] [Indexed: 11/10/2022]
Abstract
BACKGROUND/AIM Neutrons are used as a type of high linear energy transfer (LET) radiation and they have stronger carcinogenic effects compared to low LET radiation. We sought to clarify the features of mammary carcinomas for which the incidence increases when these were exposed to neutron radiation. MATERIALS AND METHODS We compared mammary carcinomas from female Sprague-Dawley rats irradiated at 7 weeks of age with 0.485 Gy neutron beams or 0.5-Gy γ rays, with carcinomas of non-irradiated rats. Tumors were classified into luminal and non-luminal subtypes based on immunohistochemistry, while their copy number aberrations were determined using microarrays. RESULTS Neutrons and γ rays significantly increased the incidence of luminal carcinomas. The carcinomas in the three groups contained multiple aberrations affecting 46 genes for which mutations have been reported in human breast cancer. CONCLUSION Neutrons and γ rays increase the incidence of luminal mammary carcinoma in rats, probably via genetic aberrations similar to those found in human breast cancer patients.
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Affiliation(s)
- Hitomi Moriyama
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan.,Department of Radiation Effects Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Kazuhiro Daino
- Department of Radiation Effects Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Tatsuhiko Imaoka
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan.,Department of Radiation Effects Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Mayumi Nishimura
- Department of Radiation Effects Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Yukiko Nishimura
- Department of Radiation Effects Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Masaru Takabatake
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan.,Department of Radiation Effects Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Takamitsu Morioka
- Department of Radiation Effects Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Masahiro Fukushi
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - Yoshiya Shimada
- National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Shizuko Kakinuma
- Department of Radiation Effects Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
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Balaghi S, Ghal-Eh N, Mohammadi A, Vega-Carrillo HR. A neutron scattering soil moisture measurement system with a linear response. Appl Radiat Isot 2018; 142:167-72. [PMID: 30326442 DOI: 10.1016/j.apradiso.2018.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 09/10/2018] [Accepted: 10/05/2018] [Indexed: 11/22/2022]
Abstract
A prototype moisture measurement system was designed and constructed, based on neutron scattering, for preforming measurements in the laboratory. The system consisted of a rectangular soil container, an 241Am/Be neutron source and two parallel 10BF3 detectors (one near the source and the other far from it). Neutrons from the source are moderated and backscattered within the soil sample before being detected by two parallel counters, whose count ratios are shown to be linearly related to the soil moisture even within short measurement times. The system's performance was demonstrated using the Monte Carlo simulations, and a series of measurements on soil samples made of clay (40 wt%) and sand (60 wt%), mixed with different percentages of water. The results showed that the detectors response ratio is linear, up to about 25% of water content.
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Cai Y, Hu H, Pan Z, Hu G, Zhang T. A method to optimize the shield compact and lightweight combining the structure with components together by genetic algorithm and MCNP code. Appl Radiat Isot 2018; 139:169-174. [PMID: 29778764 DOI: 10.1016/j.apradiso.2018.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 05/02/2018] [Accepted: 05/10/2018] [Indexed: 11/27/2022]
Abstract
To optimize the shield for neutrons and gamma rays compact and lightweight, a method combining the structure and components together was established employing genetic algorithms and MCNP code. As a typical case, the fission energy spectrum of 235U which mixed neutrons and gamma rays was adopted in this study. Six types of materials were presented and optimized by the method. Spherical geometry was adopted in the optimization after checking the geometry effect. Simulations have made to verify the reliability of the optimization method and the efficiency of the optimized materials. To compare the materials visually and conveniently, the volume and weight needed to build a shield are employed. The results showed that, the composite multilayer material has the best performance.
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Affiliation(s)
- Yao Cai
- School of Nuclear Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Huasi Hu
- School of Nuclear Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Ziheng Pan
- School of Nuclear Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Guang Hu
- School of Nuclear Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Tao Zhang
- School of Nuclear Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
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28
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Xoubi N. Neutronic design study of accelerator driven system (ADS) for Jordan subcritical reactor as a neutron source for nuclear research. Appl Radiat Isot 2017; 131:71-76. [PMID: 29173811 DOI: 10.1016/j.apradiso.2017.11.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 10/22/2017] [Accepted: 11/08/2017] [Indexed: 11/26/2022]
Abstract
In this paper, a preliminary neutronic design study of an accelerator driven subcritical system for Jordan Subcritical Assembly (JSA) is presented. The conceptual design of coupling the JSA core with proton accelerator and spallation target is investigated, and its feasibility as a neutron source for nuclear research, and possibly for target irradiation and isotope production evaluated. 3D MCNPX model of the JSA reactor, the accelerator beam, and the Pb target was developed, based on actual reactor parameters. MCNPX calculations were carried out to estimate the absolute radial and axial neutron flux in the reactor, and to calculate the multiplication factor Keff and heat generated in the reactor. Numerical results showed an enormous increase in the neutron flux, by seven orders of magnitude, compared to the current JSA core design using Pu-Be source. In this research the results obtained are discussed and compared with those of the JSA, and do confirm the feasibility of utilizing the JSA as a viable nuclear research facility with adequate neutron flux.
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Affiliation(s)
- Ned Xoubi
- Nuclear Engineering Department, King Abdulaziz University, P.O. Box: 80204, Jeddah 21589, Saudi Arabia.
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29
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Kicka L, Machrafi R, Miller A. Study of neutron fields around an intense neutron generator. Appl Radiat Isot 2017; 130:276-279. [PMID: 29065372 DOI: 10.1016/j.apradiso.2017.09.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 08/11/2017] [Accepted: 09/22/2017] [Indexed: 11/26/2022]
Abstract
Neutron fields in the vicinity of the newly built neutron facility, at the University of Ontario Institute of Technology (UOIT), have been investigated in a series of Monte Carlo simulations and measurements. The facility hosts a P-385 neutron generator based on a deuterium-deuterium fusion reaction. The neutron fluence at different locations around the neutron generator facility has been simulated using MCNPX 2.7E Monte Carlo particle transport program. To characterize neutron fields, three neutron sources were modeled with distributions corresponding to different incident deuteron energies of 90kV, 110kV, and 130kV. Measurements have been carried out to determine the dose rate at locations adjacent to the generator using bubble detectors (BDs). The neutron intensity was evaluated and the total dose rates corresponding to different applied acceleration potentials were estimated at various locations.
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Affiliation(s)
- L Kicka
- University of Ontario Institute of Technology, 2000 Simcoe Street, Oshawa, Ontario, Canada L1H4K7
| | - R Machrafi
- University of Ontario Institute of Technology, 2000 Simcoe Street, Oshawa, Ontario, Canada L1H4K7.
| | - A Miller
- University of Ontario Institute of Technology, 2000 Simcoe Street, Oshawa, Ontario, Canada L1H4K7
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Ragaliauskas T, Mickevicius M, Rakovska B, Penkauskas T, Vanderah DJ, Heinrich F, Valincius G. Fast formation of low-defect-density tethered bilayers by fusion of multilamellar vesicles. Biochim Biophys Acta Biomembr 2017; 1859:669-678. [PMID: 28088448 DOI: 10.1016/j.bbamem.2017.01.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/19/2016] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
Abstract
A facile and reproducible preparation of surface-supported lipid bilayers is essential for fundamental membrane research and biotechnological applications. We demonstrate that multilamellar vesicles fuse to molecular-anchor-grafted surfaces yielding low-defect-density, tethered bilayer membranes. Continuous bilayers are formed within 10min, while the electrically insulating bilayers with <0.1μm-2 defect density can be accomplished within 60min. Surface plasmon resonance spectroscopy indicates that an amount of lipid material transferred from vesicles to a surface is inversely proportional to the density of an anchor, while the total amount of lipid that includes tethered and transferred lipid remains constant within 5% standard error. This attests for the formation of intact bilayers independent of the tethering agent density. Neutron reflectometry (NR) revealed the atomic level structural details of the tethered bilayer showing, among other things, that the total thickness of the hydrophobic slab of the construct was 3.2nm and that the molar fraction of cholesterol in lipid content is essentially the same as the molar fraction of cholesterol in the multilamellar liposomes. NR also indicated the formation of an overlayer with an effective thickness of 1.9nm. These overlayers may be easily removed by a single rinse of the tethered construct with 30% ethanol solution. Fast assembly and low residual defect density achievable within an hour of fusion makes our tethered bilayer methodology an attractive platform for biosensing of membrane damaging agents, such as pore forming toxins.
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Affiliation(s)
- Tadas Ragaliauskas
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania
| | - Mindaugas Mickevicius
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania
| | - Bozena Rakovska
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania
| | - Tadas Penkauskas
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania
| | - David J Vanderah
- Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA
| | - Frank Heinrich
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA; Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Gintaras Valincius
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania.
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Broustas CG, Xu Y, Harken AD, Garty G, Amundson SA. Comparison of gene expression response to neutron and x-ray irradiation using mouse blood. BMC Genomics 2017; 18:2. [PMID: 28049433 PMCID: PMC5210311 DOI: 10.1186/s12864-016-3436-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 12/19/2016] [Indexed: 12/21/2022] Open
Abstract
Background In the event of an improvised nuclear device detonation, the prompt radiation exposure would consist of photons plus a neutron component that would contribute to the total dose. As neutrons cause more complex and difficult to repair damage to cells that would result in a more severe health burden to affected individuals, it is paramount to be able to estimate the contribution of neutrons to an estimated dose, to provide information for those making treatment decisions. Results Mice exposed to either 0.25 or 1 Gy of neutron or 1 or 4 Gy x-ray radiation were sacrificed at 1 or 7 days after exposure. Whole genome microarray analysis identified 7285 and 5045 differentially expressed genes in the blood of mice exposed to neutron or x-ray radiation, respectively. Neutron exposure resulted in mostly downregulated genes, whereas x-rays showed both down- and up-regulated genes. A total of 34 differentially expressed genes were regulated in response to all ≥1 Gy exposures at both times. Of these, 25 genes were consistently downregulated at days 1 and 7, whereas 9 genes, including the transcription factor E2f2, showed bi-directional regulation; being downregulated at day 1, while upregulated at day 7. Gene ontology analysis revealed that genes involved in nucleic acid metabolism processes were persistently downregulated in neutron irradiated mice, whereas genes involved in lipid metabolism were upregulated in x-ray irradiated animals. Most biological processes significantly enriched at both timepoints were consistently represented by either under- or over-expressed genes. In contrast, cell cycle processes were significant among down-regulated genes at day 1, but among up-regulated genes at day 7 after exposure to either neutron or x-rays. Cell cycle genes downregulated at day 1 were mostly distinct from the cell cycle genes upregulated at day 7. However, five cell cycle genes, Fzr1, Ube2c, Ccna2, Nusap1, and Cdc25b, were both downregulated at day 1 and upregulated at day 7. Conclusions We describe, for the first time, the gene expression profile of mouse blood cells following exposure to neutrons. We have found that neutron radiation results in both distinct and common gene expression patterns compared with x-ray radiation. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3436-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Constantinos G Broustas
- Center for Radiological Research, Columbia University Medical Center, 630 West 168th Street, New York, NY, 10032, USA
| | - Yanping Xu
- Radiological Research Accelerator Facility, Columbia University, Irvington, NY, 10533, USA
| | - Andrew D Harken
- Radiological Research Accelerator Facility, Columbia University, Irvington, NY, 10533, USA
| | - Guy Garty
- Radiological Research Accelerator Facility, Columbia University, Irvington, NY, 10533, USA
| | - Sally A Amundson
- Center for Radiological Research, Columbia University Medical Center, 630 West 168th Street, New York, NY, 10032, USA.
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Mousavi Shirazi SA, Pazirandeh A, Jahanfarnia G, Athari Allaf M. Presenting and simulating an innovative model of liver phantom and applying two methods for dosimetry of it in neutron radiation therapy. Rep Pract Oncol Radiother 2016; 22:42-51. [PMID: 27829819 DOI: 10.1016/j.rpor.2016.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 06/26/2016] [Accepted: 09/29/2016] [Indexed: 11/29/2022] Open
Abstract
AIM A new model of liver phantom is defined, then this model is simulated by MCNPX code for dosimetry in neutron radiation therapy. Additionally, an analytical method is applied based on neutrons collisions and mathematical equations to estimate absorbed doses. Finally, the results obtained from two methods are compared to each other to justify the approach. BACKGROUND The course of treatment by neutron radiation can be implemented to treat cancerous tissues, although this method has not yet been widespread. The MIRD and the Stylized Family Phantom were the first anthropomorphic phantoms, although the representation of internal organs was quite crude in them. At present, a water phantom is usually used for clinical dosimetry. MATERIALS AND METHODS Each of the materials in an adult liver tissue including water and some organic compounds is decomposed into its constituent elements based on mass percentage and density of every element. Then, the accurate mass of every decomposed material of human liver tissue is correlated to masses of the phantom components. RESULTS The absorbed doses are computed by MCNPX simulation and analytical method in all components and different layers of this phantom. CONCLUSIONS Within neutron energy range of 0.001 eV-15 MeV, the calculated doses by MCNPX code are approximately similar to results obtained by analytical method, and the derived graphs of both methods approve one another. It is also concluded that through increasing the incident neutron energy, water receives the largest amounts of absorbed doses, and carbon, nitrogen and sulfur receive correspondingly less amounts, respectively.
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Affiliation(s)
| | - Ali Pazirandeh
- Department of Nuclear Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Gholamreza Jahanfarnia
- Department of Nuclear Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Mitra Athari Allaf
- Department of Nuclear Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
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33
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Dong AX, Gwinn RP, Warner NM, Caylor LM, Doherty MJ. Mitigating bit flips or single event upsets in epilepsy neurostimulators. Epilepsy Behav Case Rep 2016; 5:72-4. [PMID: 27222798 PMCID: PMC4872716 DOI: 10.1016/j.ebcr.2016.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 04/10/2016] [Indexed: 11/10/2022]
Abstract
Objectives The objective of this study was to review software errors known as single event upsets (SEUs) or bit flips due to cosmic rays in epilepsy neurostimulators. Materials and methods A case report of a single event upset or bit flip is discussed; device manufacturers and publicly available data were queried for both incidence and types of error as well as strategies of software error mitigation. Results Neurostimulators, like other implanted devices such as pacemakers, are prone to single event upsets. Strategies for SEU mitigation are reviewed. Conclusions Cosmic radiation can threaten RAM and settings of neurostimulators; neuromodulation teams and device designers need to take this threat into account when designing multifunctional neuromodulation systems.
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Affiliation(s)
- Alice X Dong
- Department of Biochemistry, University of Washington, Seattle, WA 98105, USA
| | - Ryder P Gwinn
- Swedish Epilepsy Center, 550 17th Ave Suite 540, Seattle, WA 98122, USA
| | - Nicole M Warner
- Swedish Epilepsy Center, 550 17th Ave Suite 540, Seattle, WA 98122, USA
| | - Lisa M Caylor
- Swedish Epilepsy Center, 550 17th Ave Suite 540, Seattle, WA 98122, USA
| | - Michael J Doherty
- Swedish Epilepsy Center, 550 17th Ave Suite 540, Seattle, WA 98122, USA
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Alikaniotis K, Borla O, Monti V, Vivaldo G, Zanini A, Giannini G. Radiotherapy dose enhancement using BNCT in conventional LINACs high-energy treatment: Simulation and experiment. Rep Pract Oncol Radiother 2016; 21:117-22. [PMID: 26933394 PMCID: PMC4747660 DOI: 10.1016/j.rpor.2015.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 03/19/2015] [Accepted: 07/21/2015] [Indexed: 10/23/2022] Open
Abstract
AIM To employ the thermal neutron background that affects the patient during a traditional high-energy radiotherapy treatment for BNCT (Boron Neutron Capture Therapy) in order to enhance radiotherapy effectiveness. BACKGROUND Conventional high-energy (15-25 MV) linear accelerators (LINACs) for radiotherapy produce fast secondary neutrons in the gantry with a mean energy of about 1 MeV due to (γ, n) reaction. This neutron flux, isotropically distributed, is considered as an unavoidable undesired dose during the treatment. Considering the moderating effect of human body, a thermal neutron fluence is localized in the tumour area: this neutron background could be employed for BNCT by previously administering (10)B-Phenyl-Alanine ((10)BPA) to the patient. MATERIALS AND METHODS Monte Carlo simulations (MCNP4B-GN code) were performed to estimate the total amount of neutrons outside and inside human body during a traditional X-ray radiotherapy treatment. Moreover, a simplified tissue equivalent anthropomorphic phantom was used together with bubble detectors for thermal and fast neutron to evaluate the moderation effect of human body. RESULTS Simulation and experimental results confirm the thermal neutron background during radiotherapy of 1.55E07 cm(-2) Gy(-1). The BNCT equivalent dose delivered at 4 cm depth in phantom is 1.5 mGy-eq/Gy, that is about 3 Gy-eq (4% of X-rays dose) for a 70 Gy IMRT treatment. CONCLUSIONS The thermal neutron component during a traditional high-energy radiotherapy treatment could produce a localized BNCT effect, with a localized therapeutic dose enhancement, corresponding to 4% or more of photon dose, following tumour characteristics. This BNCT additional dose could thus improve radiotherapy, acting as a localized radio-sensitizer.
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Affiliation(s)
- Katia Alikaniotis
- Department of Physics, University of Turin, Via Pietro Giuria 1, 10126 Torino, Italy
| | - Oscar Borla
- Polytechnic of Turin, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Valeria Monti
- Department of Physics, University of Turin, Via Pietro Giuria 1, 10126 Torino, Italy
| | | | - Alba Zanini
- INFN of Turin, Via Pietro Giuria 1, 10126 Torino, Italy
| | - Gianrossano Giannini
- Department of Physics, University of Trieste and INFN of Trieste, Via Valerio 2, 34127 Trieste, Italy
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Kambali I, Suryanto H, Parwanto. Radioactive by-products of a self-shielded cyclotron and the liquid target system for F-18 routine production. Australas Phys Eng Sci Med 2016; 39:403-12. [PMID: 26867652 DOI: 10.1007/s13246-016-0426-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 01/28/2016] [Indexed: 10/22/2022]
Abstract
Routine production of F-18 radionuclide using proton beams accelerated in a cyclotron could potentially generate residual radioisotopes in the cyclotron vicinity which eventually become major safety concerns over radiation exposure to the workers. In this investigation, a typical 11-MeV proton, self-shielded cyclotron has been assessed for its residual radiation sources in the cyclotron's shielding, tank/chamber, cave wall as well as target system. Using a portable gamma ray spectroscopy system, the radiation measurement in the cyclotron environment has been carried out. Experimental results indicate that relatively long-lived radioisotopes such as Mn-54, Zn-65 and Eu-152 are detected in the inner and outer surface of the cyclotron shielding respectively while Mn-54 spectrum is observed around the cyclotron chamber. Weak intensity of Eu-152 radioisotope is again spotted in the inner and outer surface of the cyclotron cave wall. Angular distribution measurement of the Eu-152 shows that the intensity slightly drops with increasing observation angle relative to the proton beam incoming angle. In the target system, gamma rays from Co-56, Mn-52, Co-60, Mn-54, Ag-110 m are identified. TALYS-calculated nuclear cross-section data are used to study the origins of the radioactive by-products.
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Abstract
UNLABELLED Proteins belong to the most complex colloidal system in terms of their physicochemical properties, size and conformational-flexibility. This complexity contributes to their great sensitivity to any external change and dictate the uncertainty of crystallization. The need of 3D models to understand their functionality and interaction mechanisms with other neighbouring (macro)molecules has driven the tremendous effort put into the field of crystallography that has also permeated other fields trying to shed some light into reluctant-to-crystallize proteins. This review is aimed at revising protein crystallization from a regular-laboratory point of view. It is also devoted to highlight the latest developments and achievements to produce, identify and deliver high-quality protein crystals for XFEL, Micro-ED or neutron diffraction. The low likelihood of protein crystallization is rationalized by considering the intrinsic polypeptide nature (folded state, surface charge, etc) followed by a description of the standard crystallization methods (batch, vapour diffusion and counter-diffusion), including high throughput advances. Other methodologies aimed at determining protein features in solution (NMR, SAS, DLS) or to gather structural information from single particles such as Cryo-EM are also discussed. Finally, current approaches showing the convergence of different structural biology techniques and the cross-methodologies adaptation to tackle the most difficult problems, are presented. SYNOPSIS Current advances in biomacromolecules crystallization, from nano crystals for XFEL and Micro-ED to large crystals for neutron diffraction, are covered with special emphasis in methodologies applicable at laboratory scale.
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Affiliation(s)
- José A Gavira
- Laboratorio de Estudios Cristalográficos, IACT (CSIC-UGR), Avda. de las Palmeras, 4. 18100 Armilla, Granada, Spain
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Zhang J, He Y, Shen X, Jiang D, Wang Q, Liu Q, Fang W. γ-H2AX responds to DNA damage induced by long-term exposure to combined low-dose-rate neutron and γ-ray radiation. Mutat Res Genet Toxicol Environ Mutagen 2015; 795:36-40. [PMID: 26774665 DOI: 10.1016/j.mrgentox.2015.11.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 10/26/2015] [Accepted: 11/11/2015] [Indexed: 01/04/2023]
Abstract
Risk estimates for low-dose radiation (LDR) remain controversial. The possible involvement of DNA repair-related genes in long-term low-dose-rate neutron-gamma radiation exposure is poorly understood. In this study, 60 rats were divided into control groups and irradiated groups, which were exposed to low-dose-rate n-γ combined radiation (LDCR) for 15, 30, or 60 days. The effects of different cumulative radiation doses on peripheral blood cell (PBC), subsets of T cells of peripheral blood lymphocytes (PBL) and DNA damage repair were investigated. Real-time PCR and immunoblot analyses were used to detect expression of DNA DSB-repair-related genes involved in the NHEJ pathway, such as Ku70 and Ku80, in PBL. The mRNA level of H2AX and the expression level of γ-H2AX were detected by real-time PCR, immunoblot, and flow cytometry. White blood cells (WBC) and platelets (PLT) of all ionizing radiation (IR) groups decreased significantly, while no difference was seen between the 30 day and 60 day exposure groups. The numbers of CD3(+), CD4(+) T cells and CD4(+)/CD8(+) in the PBL of IR groups were lower than in the control group. In the 30 day and 60 day exposure groups, CD8(+) T cells decreased significantly. Real-time PCR and immunoblot results showed no significant difference in the mRNA and protein expression of Ku70 and Ku80 between the control groups and IR groups. However, the mRNA of H2AX increased significantly, and there was a positive correlation with dose. There was no difference in the protein expression of γ-H2AX between 30 day and 60 day groups, which may help to explain the damage to PBL. In conclusion, PBL damage increased with cumulative dose, suggesting that γ-H2AX, but neither Ku70 nor Ku80, plays an important role in PBL impairment induced by LDCR.
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Affiliation(s)
- Junlin Zhang
- College of Food Science and Engineering, Shanghai Ocean University, Shanghai 201306, China; PLA Key Laboratory of Biological Effect and Medical Protection on Warship Special Environment, Department of Protection Medicine, Naval Medical Research Institute, Shanghai 200433, China
| | - Ying He
- PLA Key Laboratory of Biological Effect and Medical Protection on Warship Special Environment, Department of Protection Medicine, Naval Medical Research Institute, Shanghai 200433, China
| | - Xianrong Shen
- PLA Key Laboratory of Biological Effect and Medical Protection on Warship Special Environment, Department of Protection Medicine, Naval Medical Research Institute, Shanghai 200433, China.
| | - Dingwen Jiang
- PLA Key Laboratory of Biological Effect and Medical Protection on Warship Special Environment, Department of Protection Medicine, Naval Medical Research Institute, Shanghai 200433, China
| | - Qingrong Wang
- PLA Key Laboratory of Biological Effect and Medical Protection on Warship Special Environment, Department of Protection Medicine, Naval Medical Research Institute, Shanghai 200433, China
| | - Qiong Liu
- PLA Key Laboratory of Biological Effect and Medical Protection on Warship Special Environment, Department of Protection Medicine, Naval Medical Research Institute, Shanghai 200433, China
| | - Wen Fang
- Department of Biological Engineering, China Pharmaceutical University, Nanjing 211198, China
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Pöllänen R, Siiskonen T. Detection of fast neutrons from shielded nuclear materials using a semiconductor alpha detector. Appl Radiat Isot 2014; 90:187-91. [PMID: 24792122 DOI: 10.1016/j.apradiso.2014.03.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 02/26/2014] [Accepted: 03/24/2014] [Indexed: 10/25/2022]
Abstract
The response of a semiconductor alpha detector to fast (>1 MeV) neutrons was investigated by using measurements and simulations. A polyethylene converter was placed in front of the detector to register recoil protons generated by elastic collisions between neutrons and hydrogen nuclei of the converter. The developed prototype equipment was tested with shielded radiation sources. The low background of the detector and insensitivity to high-energy gamma rays above 1 MeV are advantages when the detection of neutron-emitting nuclear materials is of importance. In the case of a (252)Cf neutron spectrum, the intrinsic efficiency of fast neutron detection was determined to be 2.5×10(-4), whereas three-fold greater efficiency was obtained for a (241)AmBe neutron spectrum.
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Affiliation(s)
- R Pöllänen
- STUK - Radiation and Nuclear Safety Authority, P.O. Box 14, FI-00881 Helsinki, Finland.
| | - T Siiskonen
- STUK - Radiation and Nuclear Safety Authority, P.O. Box 14, FI-00881 Helsinki, Finland
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39
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Milenkovic B, Stevanovic N, Nikezic D, Kosutic D. Determination of a CR-39 detector response to neutrons from an Am-Be source. Appl Radiat Isot 2014; 90:225-8. [PMID: 24814609 DOI: 10.1016/j.apradiso.2014.04.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 02/03/2014] [Accepted: 04/06/2014] [Indexed: 11/18/2022]
Abstract
A comparison of experimental and calculated responses of a CR-39 detector to neutron spectra from an Am-Be source is presented. Code named Neutron_CR-39.F90 has been used to calculate the neutron dose equivalent as well as the track density. Conversion coefficient (sensitivity), between track density in track/cm(2) and neutron dose equivalent in mSv, was calculated and good agreement with experimental data was found. Sensitivity increases linearly with removed layer in the range between 6 μm and 24 μm.
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Affiliation(s)
- B Milenkovic
- University of Kragujevac, Faculty of Science, R. Domanovica 12, 34000 Kragujevac, Serbia
| | - N Stevanovic
- University of Kragujevac, Faculty of Science, R. Domanovica 12, 34000 Kragujevac, Serbia
| | - D Nikezic
- University of Kragujevac, Faculty of Science, R. Domanovica 12, 34000 Kragujevac, Serbia.
| | - D Kosutic
- Vinca Institute of Nuclear Sciences, Radiation Protection Laboratory, M.P. Alasa 12-14, Vinca, P.O. Box 522, 11001 Belgrade, Serbia
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Abstract
With the advance of modern radiation therapy technique, radiation dose conformation and dose distribution have improved dramatically. However, the progress does not completely fulfill the goal of cancer treatment such as improved local control or survival. The discordances with the clinical results are from the biophysical nature of photon, which is the main source of radiation therapy in current field, with the lower linear energy transfer to the target. As part of a natural progression, there recently has been a resurgence of interest in particle therapy, specifically using heavy charged particles, because these kinds of radiations serve theoretical advantages in both biological and physical aspects. The Korean government is to set up a heavy charged particle facility in Korea Institute of Radiological & Medical Sciences. This review introduces some of the elementary physics of the various particles for the sake of Korean radiation oncologists' interest.
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Affiliation(s)
- Seo Hyun Park
- Department of Radiation Oncology, Kyung Hee University School of Medicine, Seoul, Korea
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Voyant C, Roustit R, Tatje J, Biffi K, Leschi D, Briançon J, Marcovici CL. Therapeutic potential of atmospheric neutrons. Rep Pract Oncol Radiother 2011; 16:21-31. [PMID: 24669300 PMCID: PMC3920293 DOI: 10.1016/j.rpor.2010.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 10/05/2010] [Accepted: 11/03/2010] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND Glioblastoma multiform (GBM) is the most common and most aggressive type of primary brain tumour in humans. It has a very poor prognosis despite multi-modality treatments consisting of open craniotomy with surgical resection, followed by chemotherapy and/or radiotherapy. Recently, a new treatment has been proposed - Boron Neutron Capture Therapy (BNCT) - which exploits the interaction between Boron-10 atoms (introduced by vector molecules) and low energy neutrons produced by giant accelerators or nuclear reactors. METHODS The objective of the present study is to compute the deposited dose using a natural source of neutrons (atmospheric neutrons). For this purpose, Monte Carlo computer simulations were carried out to estimate the dosimetric effects of a natural source of neutrons in the matter, to establish if atmospheric neutrons interact with vector molecules containing Boron-10. RESULTS The doses produced (an average of 1 μGy in a 1 g tumour) are not sufficient for therapeutic treatment of in situ tumours. However, the non-localised yet specific dosimetric properties of 10B vector molecules could prove interesting for the treatment of micro-metastases or as (neo)adjuvant treatment. On a cellular scale, the deposited dose is approximately 0.5 Gy/neutron impact. CONCLUSION It has been shown that BNCT may be used with a natural source of neutrons, and may potentially be useful for the treatment of micro-metastases. The atmospheric neutron flux is much lower than that utilized during standard NBCT. However the purpose of the proposed study is not to replace the ordinary NBCT but to test if naturally occurring atmospheric neutrons, considered to be an ionizing pollution at the Earth's surface, can be used in the treatment of a disease such as cancer. To finalize this study, it is necessary to quantify the biological effects of the physically deposited dose, taking into account the characteristics of the incident particles (alpha particle and Lithium atom) and radio-induced effects (by-stander and low dose effect). One of the aims of the presented paper is to propose to experimental teams (which would be interested in studying the phenomena) a simple way to calculate the dose deposition (allometric fit of free path, transmission factor of brain).
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Affiliation(s)
- Cyril Voyant
- University of Corsica, CNRS UMR SPE 6134, Campus Grimaldi, 20250 Corte, France
- Castelluccio Hospital, Radiotherapy Unit, BP 85, 20177 Ajaccio, France
| | - Rudy Roustit
- Castelluccio Hospital, Radiotherapy Unit, BP 85, 20177 Ajaccio, France
| | - Jennifer Tatje
- Castelluccio Hospital, Radiotherapy Unit, BP 85, 20177 Ajaccio, France
| | - Katia Biffi
- Castelluccio Hospital, Radiotherapy Unit, BP 85, 20177 Ajaccio, France
| | - Delphine Leschi
- Castelluccio Hospital, Radiotherapy Unit, BP 85, 20177 Ajaccio, France
| | - Jérome Briançon
- Castelluccio Hospital, Radiotherapy Unit, BP 85, 20177 Ajaccio, France
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42
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Wang RJ, Peng RY, Fu KF, Gao YB, Han RG, Hu WH, Luo QL, Ma JJ. Effect of recombinant human interleukin-11 on expressions of interleukin-11 receptor α-chain and glycoprotein 130 in intestinal epithelium cell line-6 after neutron irradiation. World J Gastroenterol 2006; 12:3055-9. [PMID: 16718787 PMCID: PMC4124381 DOI: 10.3748/wjg.v12.i19.3055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the effect of recombinant human interleukin-11 (rhIL-11) on the expressions of interleukin-11 receptor α-chain (IL-11Rα) and an additional signal transducer glycoprotein 130 (gp130) in intestinal epithelium cell line-6 (IEC-6) after neutron irradiation.
METHODS: Cultured IEC-6 cells were exposed to 4.0Gy neutron and treated with 100 ng/mL rhIL-11 12 h prior to or immediately after irradiation. The apoptosis and necrosis rates and expressions of IL-11Rα and gp130 were observed by flow cytometry, immunohistochemistry, Western blot and image analysis.
RESULTS: The apoptosis rate of IEC-6 cells was increased by irradiation at 6 h (P < 0.01), IL-11 stimulation resulted in a decreased apoptosis rate in irradiated IEC-6 cells (P < 0.05). In normal control IEC-6 cells, intense immunoreactivity of IL-11Rα was located within the cell membrane and cytoplasm. The level of IL-11Rα expression significantly decreased at 6 h after irradiation (P < 0.01) and restored at 24 h after irradiation. In IEC-6 cells treated with both radiation and rhIL-11, the level of IL-11Rα expression was higher than that of irradiated cells (P < 0.05). When it came to gp130 protein, it was located in the cytoplasm of IEC-6 cells. After irradiation, we found a progressive decrease in the expression of gp130 protein (P < 0.05) in 48 h post-radiation, while in rhIL-11-stimulated cells, it came back to normal level at 24 h after irradiation and decreased at 48 h, but was still higher than that of only irradiated cells (P < 0.05).
CONCLUSION: rhIL-11 can protect IEC-6 cells from neutron irradiation. The protective effect of rhIL-11 might be connected with its ability to up-regulate the expressions of specific ligand-binding subunit IL-11Rα and signal-transducing subunit gp130.
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Affiliation(s)
- Rui-Juan Wang
- Institute of Radiation Medicine, Academy of Military Medical Sciences, Beijing 100850, China
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