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Sample records for bnct neutron irradiation

  1. Proceedings of neutron irradiation technical meeting on BNCT

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-10-01

    The 'Neutron Irradiation Technical Meeting for Boron Neutron Capture Therapy (BNCT)' was held on March 13, 2000 at Tokai Research Establishment. The Meeting is aimed to introduce the neutron beam facility for medical irradiation at JRR-4 to Japanese researchers widely, as well as providing an opportunity for young researchers, engineers, medical representatives such surgeons and doctors of pharmacology to present their research activities and to exchange valuable information. JAERI researcher presented the performance and the irradiation technology in the JRR-4 neutron beam facility, while external researchers made various and beneficial presentations containing such accelerator-based BNCT, spectrum-shifter, biological effect, pharmacological development and so on. In this meeting, a special lecture titled 'The Dawn of BNCT and Its Development.' was given by MD, Prof. Takashi Minobe, an executive director of Japan Foundation for Emergency Medicine. The 11 of the presented papers are indexed individually. (J.P.N.)

  2. Evaluation of D(d,n)3 He reaction neutron source models for BNCT irradiation system design

    Institute of Scientific and Technical Information of China (English)

    YAO Ze'en; LUO Peng; Tooru KOBAYASHI; Gerard BENGUA

    2007-01-01

    A mathematical method was developed to calculatc the yield.energy spectrum and angular distribution of neutrons from D(d,n)3 He(D-D)reaction in a thick deuterium-titanium target for incident deuterons in energies lower than 1.0MeV.The data of energy spectrum and angular distribution wefe applied to set up the neutron source model for the beam-shaping-assembly(BSA)design of Boron-Neutron-Capture-Therapy(BNCT)using MCNP-4C code.Three cases of D-D neutron source corresponding to incident deuteron energy of 1000.400 and 150 kaV were investigated.The neutron beam characteristics were compared with the model of a 2.45 MeV mono-energetic and isotropic neutron source using an example BSA designed for BNCT irradiation.The results show significant differences in the neutron beam characteristics,particularly the fast neutron component and fast neutron dose in air,between the non-isotropic neutron source model and the 2.5 MeV mono-energetic and isotropic neutron source model.

  3. BNCT irradiation facility at the JRR-4

    Energy Technology Data Exchange (ETDEWEB)

    Torii, Y.; Kishi, T.; Kumada, H.; Yamamoto, K.; Sakurai, F.; Takayanagi, M. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2000-10-01

    The JRR--4 was modified for fuel enrichment reducing and reactor equipment renewal. And also a medical irradiation facility for the Boron Neutron Capture Therapy (BNCT) was installed at the JRR--4 in that time. The medical irradiation facility has been composed of a heavy water tank, a collimator and an irradiation room. The heavy water tank has four layers of heavy water for spectrum shifter and 75cm-thickness aluminum for the shield of fast neutron. The collimator is for collimating thermal neutron and epithermal neutron using polyethylene with lithium-fluoride and shielding gamma ray by bismuth. The irradiation room has sufficient space at exit side of the beam, to accommodate a large working area for setting the patient. Both of the medical treatment room and the patient-monitoring area were prepared adjacent to the irradiation room. The medical irradiation facility in the JRR-4 is designed to permit selection of neutron energies from thermal neutron to epithermal neutron by changing the thickness of heavy water layers. Therefore it is available to continue the same kind of BNCT with thermal neutron used to perform in the JRR-2, as well as to commence the research and development of BNCT with epithermal neutron, which will make the brain tumor treatment possible at a deep part of brain. The full power operation of the JRR-4 was resumed with LEU fuel in October 1998 and currently performing some experiments to measure the neutron fluxes and physical doses for determinate characterization of the medical irradiation facility. The first medical irradiation for BNCT was carried out on 25th October 1999. The patient was treated by Tsukuba University group using thermal neutron beam included epi-thermal neutrons. (author)

  4. Advances in boron neutron capture therapy (BNCT) at kyoto university - From reactor-based BNCT to accelerator-based BNCT

    Science.gov (United States)

    Sakurai, Yoshinori; Tanaka, Hiroki; Takata, Takushi; Fujimoto, Nozomi; Suzuki, Minoru; Masunaga, Shinichiro; Kinashi, Yuko; Kondo, Natsuko; Narabayashi, Masaru; Nakagawa, Yosuke; Watanabe, Tsubasa; Ono, Koji; Maruhashi, Akira

    2015-07-01

    At the Kyoto University Research Reactor Institute (KURRI), a clinical study of boron neutron capture therapy (BNCT) using a neutron irradiation facility installed at the research nuclear reactor has been regularly performed since February 1990. As of November 2014, 510 clinical irradiations were carried out using the reactor-based system. The world's first accelerator-based neutron irradiation system for BNCT clinical irradiation was completed at this institute in early 2009, and the clinical trial using this system was started in 2012. A shift of BCNT from special particle therapy to a general one is now in progress. To promote and support this shift, improvements to the irradiation system, as well as its preparation, and improvements in the physical engineering and the medical physics processes, such as dosimetry systems and quality assurance programs, must be considered. The recent advances in BNCT at KURRI are reported here with a focus on physical engineering and medical physics topics.

  5. Measurement of thermal neutron flux for BNCT in JRR-2

    International Nuclear Information System (INIS)

    For Boron Neutron Capture Therapy (BNCT) on brain tumor, a medical irradiation facility has been installed in the Japan Research Reactor No.2 (JRR-2) in Japan Atomic Energy Research Institute (JAERI). The first BNCT using by this facility was performed in August 1990. Since then, irradiations for 15 BNCT were performed until March 1993 in JRR-2. Two kinds of devices has been equipped for the measurement of thermal neutron flux at the diseased part of patients. The one is for the measurement of activation of thin gold wire using β-γ coincidence equipment, and the other is for the simultaneous monitoring of neutron fluxes during BNCT using silicon semiconductor detectors. The measurements using these devices are reported in this paper. (author)

  6. Production of epithermal neutron beams for BNCT

    CERN Document Server

    Bisceglie, E; Colonna, N; Paticchio, V; Santorelli, P; Variale, V

    2002-01-01

    The use of boron neutron capture therapy (BNCT) for the treatment of deep-seated tumors requires neutron beams of suitable energy and intensity. Simulations indicate the optimal energy to reside in the epithermal region, in particular between 1 and 10 keV. Therapeutic neutron beams with high spectral purity in this energy range could be produced with accelerator-based neutron sources through a suitable neutron-producing reaction. Herein, we report on different solutions that have been investigated as possible sources of epithermal neutron beams for BNCT. The potential use of such sources for a hospital-based therapeutic facility is discussed.

  7. The status of Tsukuba BNCT trial: BPA-based boron neutron capture therapy combined with X-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, T., E-mail: tetsu_tsukuba@yahoo.co.jp [Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan)] [Department of Radiation Oncology, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan); Nakai, K. [Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan); Nariai, T. [Department of Neurosurgery, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo (Japan); Kumada, H.; Okumura, T.; Mizumoto, M.; Tsuboi, K. [Department of Radiation Oncology, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan); Zaboronok, A.; Ishikawa, E.; Aiyama, H.; Endo, K.; Takada, T.; Yoshida, F.; Shibata, Y.; Matsumura, A. [Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan)

    2011-12-15

    The phase II trial has been prepared to assess the effectiveness of BPA (250 mg/kg)-based NCT combined with X-ray irradiation and temozolomide (75 mg/m{sup 2}) for the treatment of newly diagnosed GBM. BPA uptake is determined by {sup 18}F-BPA-PET and/or {sup 11}C-MET-PET, and a tumor with the lesion to normal ratio of 2 or more is indicated for BNCT. The maximum normal brain point dose prescribed was limited to 13.0 Gy or less. Primary end point is overall survival.

  8. A novel BNCT irradiation system with an on-line monitor using 7Li(P,N)7Be near threshold neutrons

    International Nuclear Information System (INIS)

    A neutron irradiation system for boron neutron capture therapy using accelerators with an online dose monitoring system was studied for the possible practical implementation of hospital-based BNCT. For this purpose the neutrons produced by the near threshold 7Li(p,n)7Be reaction, i.e. an incident proton energy of around 1.90 MeV, have suitable properties. Such as the maximum energy below 100 keV and mostly forward-directed. A good candidate material to shield gamma rays from the Li-target was Lead and the suitable boron-dose enhancer was polyethylene. The optimum physical dimensions and configuration of the irradiation system was determined using the concept of treatbale protocol depth as figures of merit. For the online monitor system, the single photon emission computed tomography using prompt gamma-ray was studied to provide an ideal dose estimation system. A neutron producing target system with a liquid lithium jet flow of about 30 m/s at a thickness of 1 mm and a cross-sectional area of 50 mm × 50 mm is proposed.

  9. An Accelerator Neutron Source for BNCT

    International Nuclear Information System (INIS)

    The overall goal of this project was to develop an accelerator-based neutron source (ABNS) for Boron Neutron Capture Therapy (BNCT). Specifically, our goals were to design, and confirm by measurement, a target assembly and a moderator assembly that would fulfill the design requirements of the ABNS. These design requirements were (1) that the neutron field quality be as good as the neutron field quality for the reactor-based neutron sources for BNCT, (2) that the patient treatment time be reasonable, (3) that the proton current required to treat patients in reasonable times be technologically achievable at reasonable cost with good reliability, and accelerator space requirements which can be met in a hospital, and finally (4) that the treatment be safe for the patients

  10. An Accelerator Neutron Source for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Blue, Thomas, E

    2006-03-14

    The overall goal of this project was to develop an accelerator-based neutron source (ABNS) for Boron Neutron Capture Therapy (BNCT). Specifically, our goals were to design, and confirm by measurement, a target assembly and a moderator assembly that would fulfill the design requirements of the ABNS. These design requirements were 1) that the neutron field quality be as good as the neutron field quality for the reactor-based neutron sources for BNCT, 2) that the patient treatment time be reasonable, 3) that the proton current required to treat patients in reasonable times be technologially achievable at reasonable cost with good reliability, and accelerator space requirements which can be met in a hospital, and finally 4) that the treatment be safe for the patients.

  11. The Finnish Boron neutron capture therapy (BNCT) project

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a new, binary radiotherapy, which has been developed especially for severe brain tumours, incurable by the present means. A suitable 10B containing carrier compound is injected into the blood circulation and taken up selectively by the cancer cells. When these cells are subjected to a thermal neutron field, the 10B atoms capture the neutrons and undergo fission reaction. The energy thereby released is killing the cancerous cell. The Finnish BNCT research and development project is in the situation where all the basic conditions exist to start clinical trials. An epithermal neutron irradiation facility has been constructed at the Finnish research reactor (FiR 1) operated by VTT in Otaniemi. This article is an overview over the developments within the Finnish BNCT project. A research project to carry out clinical application of BNCT was established in Finland in the early 1990's. It was motivated both by the need to create new uses for FiR 1 and by the ideas to start research and production of new boron carriers for BNCT in Finland. Soon also other medical, medical physics and chemistry disciplines joined the project. Now the project involves scientists from different departments of University of Helsinki (HU), Helsinki University Central Hospital (HUCH), Technical Research Centre of Finland (VTT), Finnish Radiation and Nuclear Safety Authority (STUK) and of the Helsinki University of Technology (HUT) and other Finnish universities. The aim of this project has been to start BNC-treatment of malignant brain tumours in Finland by the end of the century

  12. A feasibility study of the Tehran research reactor as a neutron source for BNCT

    International Nuclear Information System (INIS)

    Investigation on the use of the Tehran Research Reactor (TRR) as a neutron source for Boron Neutron Capture Therapy (BNCT) has been performed by calculating and measuring energy spectrum and the spatial distribution of neutrons in all external irradiation facilities, including six beam tubes, thermal column, and the medical room. Activation methods with multiple foils and a copper wire have been used for the mentioned measurements. The results show that (1) the small diameter and long length beam tubes cannot provide sufficient neutron flux for BNCT; (2) in order to use the medical room, the TRR core should be placed in the open pool position, in this situation the distance between the core and patient position is about 400 cm, so neutron flux cannot be sufficient for BNCT; and (3) the best facility which can be adapted for BNCT application is the thermal column, if all graphite blocks can be removed. The epithermal and fast neutron flux at the beginning of this empty column are 4.12×109 and 1.21×109 n/cm2/s, respectively, which can provide an appropriate neutron beam for BNCT by designing and constructing a proper Beam Shaping Assembly (BSA) structure. - Highlights: • The feasibility of using of TRR for BNCT has been investigated. • Neutron energy spectrum at all external irradiation facilities of TRR have been measured and calculated. • Spatial distribution of neutrons have been measured using copper wire activation method

  13. Study of neutron medical irradiation facility with supermirror neutron guide tube in JRR-3M

    International Nuclear Information System (INIS)

    A medical irradiation facility using a supermirror guide tube has been designed for boron neutron capture therapy (BNCT) treatment at the JRR-3M. Intense thermal neutrons are obtained with lower fast neutrons and gamma rays contamination at the end of neutron guide tube. It would be a most suitable neutron field for BNCT treatment. (author)

  14. Boron Neutron Capture Therapty (BNCT) in an Oral Precancer Model: Therapeutic Benefits and Potential Toxicity of a Double Application of BNCT with a Six-Week Interval

    Energy Technology Data Exchange (ETDEWEB)

    Andrea Monti Hughes; Emiliano C.C. Pozzi; Elisa M. Heber; Silvia Thorp; Marcelo Miller; Maria E. Itoiz; Romina F. Aromando; Ana J. Molinari; Marcela A. Garabalino; David W. Nigg; Veronica A. Trivillin; Amanda E. Schwint

    2011-11-01

    Given the clinical relevance of locoregional recurrences in head and neck cancer, we developed a novel experimental model of premalignant tissue in the hamster cheek pouch for long-term studies and demonstrated the partial inhibitory effect of a single application of Boron Neutron Capture Therapy (BNCT) on tumor development from premalignant tissue. The aim of the present study was to evaluate the effect of a double application of BNCT with a 6 week interval in terms of inhibitory effect on tumor development, toxicity and DNA synthesis. We performed a double application, 6 weeks apart, of (1) BNCT mediated by boronophenylalanine (BPA-BNCT); (2) BNCT mediated by the combined application of decahydrodecaborate (GB-10) and BPA [(GB-10 + BPA)-BNCT] or (3) beam-only, at RA-3 nuclear reactor and followed the animals for 8 months. The control group was cancerized and sham-irradiated. BPA-BNCT, (GB- 10 + BPA)-BNCT and beam-only induced a reduction in tumor development from premalignant tissue that persisted until 8, 3, and 2 months respectively. An early maximum inhibition of 100% was observed for all 3 protocols. No normal tissue radiotoxicity was detected. Reversible mucositis was observed in premalignant tissue, peaking at 1 week and resolving by the third week after each irradiation. Mucositis after the second application was not exacerbated by the first application. DNA synthesis was significantly reduced in premalignant tissue 8 months post-BNCT. A double application of BPA-BNCT and (GB-10 + BPA)-BNCT, 6 weeks apart, could be used therapeutically at no additional cost in terms of radiotoxicity in normal and dose-limiting tissues.

  15. Boron Neutron Capture Therapy (BNCT) in an Oral Precancer Model: Therapeutic Benefits and Potential Toxicity of a Double Application of BNCT with a Six-Week Interval

    International Nuclear Information System (INIS)

    Given the clinical relevance of locoregional recurrences in head and neck cancer, we developed a novel experimental model of premalignant tissue in the hamster cheek pouch for long-term studies and demonstrated the partial inhibitory effect of a single application of Boron Neutron Capture Therapy (BNCT) on tumor development from premalignant tissue. The aim of the present study was to evaluate the effect of a double application of BNCT with a 6 week interval in terms of inhibitory effect on tumor development, toxicity and DNA synthesis. We performed a double application, 6 weeks apart, of (1) BNCT mediated by boronophenylalanine (BPA-BNCT); (2) BNCT mediated by the combined application of decahydrodecaborate (GB-10) and BPA ((GB-10 + BPA)-BNCT) or (3) beam-only, at RA-3 nuclear reactor and followed the animals for 8 months. The control group was cancerized and sham-irradiated. BPA-BNCT, (GB- 10 + BPA)-BNCT and beam-only induced a reduction in tumor development from premalignant tissue that persisted until 8, 3, and 2 months respectively. An early maximum inhibition of 100% was observed for all 3 protocols. No normal tissue radiotoxicity was detected. Reversible mucositis was observed in premalignant tissue, peaking at 1 week and resolving by the third week after each irradiation. Mucositis after the second application was not exacerbated by the first application. DNA synthesis was significantly reduced in premalignant tissue 8 months post-BNCT. A double application of BPA-BNCT and (GB-10 + BPA)-BNCT, 6 weeks apart, could be used therapeutically at no additional cost in terms of radiotoxicity in normal and dose-limiting tissues.

  16. Shielding design of a treatment room for an accelerator-based epithermal neutron irradiation facility for BNCT

    International Nuclear Information System (INIS)

    Protecting the facility personnel and the general public from radiation exposure is a primary safety concern of an accelerator-based epithermal neutron irradiation facility. This work makes an attempt at answering the questions open-quotes How much?close quotes and open-quotes What kind?close quotes of shielding will meet the occupational limits of such a facility. Shielding effectiveness is compared for ordinary and barytes concretes in combination with and without borated polyethylene. A calculational model was developed of a treatment room, patient open-quotes scatterer,close quotes and the epithermal neutron beam. The Monte Carlo code, MCNP, was used to compute the total effective dose equivalent rates at specific points of interest outside of the treatment room. A conservative occupational effective dose rate limit of 0.01 mSv h-1 was the guideline for this study. Conservative Monte Carlo calculations show that constructing the treatment room walls with 1.5 m of ordinary concrete, 1.2 m of barytes concrete, 1.0 m of ordinary concrete preceded by 10 cm of 5% boron-polyethylene, or 0.8 m of barytes concrete preceded by 10 cm of 5% boron-polyethylene will adequately protect facility personnel. 20 refs., 8 figs., 2 tabs

  17. Clinical results of boron neutron capture therapy (BNCT) for glioblastoma

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the clinical outcome of BSH-based intra-operative BNCT (IO-BNCT) and BSH and BPA-based non-operative BNCT (NO-BNCT). We have treated 23 glioblastoma patients with BNCT without any additional chemotherapy since 1998. The median survival time (MST) of BNCT was 19.5 months, and 2-year, 3-year and 5-year survival rates were 26.1%, 17.4% and 5.8%, respectively. This clinical result of BNCT in patients with GBM is superior to that of single treatment of conventional radiotherapy compared with historical data of conventional treatment. - Highlights: ► In this study, we evaluate the clinical outcome of boron neutron capture therapy (BNCT) for malignant brain tumors. ► We have treated 23 glioblastoma (GBM) patients with BNCT without any additional chemotherapy. ► Clinical results of BNCT in patients with GBM are superior to that of single treatment of conventional radiotherapy compared with historical data of conventional treatment.

  18. Mass spectral investigations of boron neutron capture therapy (BNCT) agents

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a promising technique for the treatment of selected types of brain tumor and potentially for other tumor types. In this therapy, a 10B-enriched species is administered to the bloodstream and selectively deposited in the tumor. The selective deposition in the tumor is due to either the breakdown of the blood-grain barrier or to the chemical nature of the boron-containing compounds. Once a sufficient concentration of boron is attained in the tumor (approximately 25 ppm), the tumor is irradiated with a controlled energy neutron beam (preferable epithermal, 1 eV to 10 keV), at which time neutrons are captured by the incorporated boron atoms. The capture results in the reaction, 10B(n, ) Li, which produces a localized nuclear reaction capable of destroying the tumor cell containing the boron. A variety of boron containing compounds have been evaluated for use in BNCT. This paper addresses some of the most promising of the compounds, the disodium salt of mercaptoundecahydrododecaborate (Na2B12H11SH), commonly referred to as BSH

  19. Boron neutron capture therapy (BNCT) selectively destroys human clear cell sarcoma in mouse model

    International Nuclear Information System (INIS)

    Clear cell sarcoma of tendons and aponeuroses (CCS) is a rare malignant tumor with no effective treatment. This study demonstrates the efficacy of BNCT with the use of human CCS-bearing nude mice. Groups A and C were administered saline, and groups B and D were injected with p-borono-L-phenylalanine-fructose complex. Groups C and D were then irradiated with thermal neutrons. The tumors in only group D disappeared, demonstrating that BNCT is a potentially new option for the treatment of human CCS. - Highlights: ► Human clear cell sarcoma (CCS)-bearing nude mice were used in this study. ► The human CCS in the nude mice disappeared after BNCT. ► The efficacy of BNCT for human CCS is demonstrated here for the first time

  20. Optimization of the irradiation beam in the BNCT research facility at IEA-R1 reactor

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy (BNCT) is a radiotherapeutic technique for the treatment of some types of cancer whose useful energy comes from a nuclear reaction that occurs when thermal neutron impinges upon a Boron-10 atom. In Brazil there is a research facility built along the beam hole number 3 of the IEA-R1 research reactor at IPEN, which was designed to perform BNCT research experiments. For a good performance of the technique, the irradiation beam should be mostly composed of thermal neutrons with a minimum as possible gamma and above thermal neutron components. This work aims to monitor and evaluate the irradiation beam on the sample irradiation position through the use of activation detectors (activation foils) and also to propose, through simulation using the radiation transport code, MCNP, new sets of moderators and filters which shall deliver better irradiation fields at the irradiation sample position In this work, a simulation methodology, based on a MCNP card, known as wwg (weight window generation) was studied, and the neutron energy spectrum has been experimentally discriminated at 5 energy ranges by using a new set o activation foils. It also has been concluded that the BNCT research facility has the required thermal neutron flux to perform studies in the area and it has a great potential for improvement for tailoring the irradiation field. (author)

  1. An in-phantom comparison of neutron fields for BNCT

    International Nuclear Information System (INIS)

    Previously, the authors have developed the in-phantom neutron field assessment parameters T and D (Tumor) for the evaluation of epithermal neutron fields for use in BNCT. These parameters are based on an energy-spectrum-dependent neutron normal-tissue RBE and the treatment planning methodology of Gahbauer and his co-workers, which includes the effects of dose fractionation. In this paper, these neutron field assessment parameters were applied to The Ohio State University (OSU) design of an Accelerator Based Neutron Source (ABNS) (hereafter called the OSU-ABNS) and the Brookhaven Medical Research Reactor (BMRR) epithermal neutron beam (hereafter called the BMRR-ENB), in order to judge the suitability of the OSU-ABNS for BNCT. The BMRR-ENB was chosen as the basis for comparison because it is presently being used in human clinical trials of BNCT and because it is the standard to which other neutron beams are most often compared

  2. Conceptual design of epithermal neutron beam for BNCT in the thermalizing column of TRIGA reactor

    International Nuclear Information System (INIS)

    The Monte Carlo feasibility study of development of the epithermal neutron beam for BNCT clinical trials in thermalising column (TC) of TRIGA reactor is presented. The investigation of the possible use of fission converter as well as the set-up of TRIGA reactor core is performed. The optimization of the irradiation facility components is carried out and the configuration with the most favorable cost/performance ratio is proposed. The results prove, that a BNCT irradiation facility with performances, comparable to existing beams throughout the world, could be installed in TC/DC of the TRIGA reactor, quite suitable for the clinical treatments of human patients.(author)

  3. Accelerator based-boron neutron capture therapy (BNCT)-clinical QA and QC

    International Nuclear Information System (INIS)

    Alpha-particle and recoil Li atom yielded by the reaction (10B, n), due to their high LET properties, efficiently and specifically kill the cancer cell that has incorporated the boron. Efficacy of this boron neutron capture therapy (BNCT) has been demonstrated mainly in the treatment of recurrent head/neck and malignant brain cancers in Kyoto University Research Reactor Institute (KUR). As the clinical trial of BNCT is to start from 2009 based on an accelerator (not on the Reactor), this paper describes the tentative outline of the standard operation procedure of BNCT for its quality assurance (QA) and quality control (QC) along the flow of its clinical practice. Personnel concerned in the practice involve the attending physician, multiple physicians in charge of BNCT, medical physicists, nurses and reactor stuff. The flow order of the actual BNCT is as follows: Pre-therapeutic evaluation mainly including informed consent and confirmation of the prescription; Therapeutic planning including setting of therapy volume, and of irradiation axes followed by meeting for stuffs' agreement, decision of irradiating field in the irradiation room leading to final decision of the axis, CT for the planning, decision of the final therapeutic plan according to Japan Atomic Energy Agency-Computational Dosimetry System (JCDS) and meeting of all related personnel for the final confirmation of therapeutic plan; and BNCT including the transport of patient to KUR, dripping of boronophenylalanine, setting up of the patient on the machine, blood sampling for pharmacokinetics, boron level measurement for decision of irradiating time, switch on/off of the accelerator, confirmation of patient's movement in the irradiated field after the neutron irradiation, blood sampling for confirmation of the boron level, and patient's leave from the room. The QA/QC check is principally to be conducted with the two-person rule. The purpose of the clinical trial is to establish the usefulness of BNCT, and

  4. Boron Neutron Capture Therapy (BNCT) in an experimental model of lung metastases in BDIX rats

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy (BNCT) in an experimental model of lung metastases in BDIX rats Introduction: Boron Neutron Capture Therapy (BNCT) is based on selective tumor uptake of boron compounds, followed by neutron irradiation. BNCT was proposed for the treatment of unresectable, diffuse lung metastases. The aim of the present study was to perform BNCT studies in an experimental model of lung metastases. Materials and Methods: 3 x 106/0.5 ml colon carcinoma cells (DHD/K12/TRb) were injected iv in syngeneic BDIX rats. Three weeks post-inoculation, rats with diffuse lung metastases were used for in vivo BNCT studies in the RA-3 Nuclear Reactor. Based on previous biodistribution studies and computational dosimetry with Monte Carlo simulation, 2 doses were prescribed, i.e. 4 Gy and 8 Gy minimum absorbed dose to tumor. The animals were assigned to 5 experimental groups (n= 4 to 8) at each dose level: T0 (euthanized pre-treatment), BPA-BNCT, Comb-BNCT (BPA+GB-10), Beam only (background dose) and Sham (same manipulation, no treatment). Boron concentration was measured in a blood sample taken pre-irradiation to verify that the value was in the range established in previous biodistribution studies. The animals were followed clinically for 2 weeks after neutron irradiation and then euthanized to assess the response of tumor and normal lung, macroscopically and histologically. To date we have evaluated the end-point weight of lung (normal lung + metastases) and % lung weight/body weight as an indicator of tumor growth. Results: The statistical analysis (ANOVA) of % lung weight/body weight showed statistically significant differences (p<0.05) between groups T0 (0.79 ± 0.38) and Sham (1.87 ± 0.91). No statistically significant differences were observed between the Beam only groups (at both dose levels) and Sham. Similar and statistically significant tumor control was induced in the groups BPA-BNCT Low dose (LD) (0.56 ± 0.11), BPA-BNCT High dose (HD) (0.80 ± 0.16), Comb-BNCT

  5. Estimation of photon and neutron dose distributions in the THOR BNCT treatment room using dual TLD method

    International Nuclear Information System (INIS)

    Dual detector dosimetry using the paired detectors, TLD-600 and TLD-700 chips, were selected in this study to distinguish the doses of neutrons and photons in Tsing Hua Open-pool Reactor (THOR) boron neutron capture therapy (BNCT) preclinical test. Since the neutron response of TLD is dependent on the neutron spectrum, responses of TLD-600 and TLD-700 for neutrons and photons were estimated by irradiation methods and in addition the effect of the neutron spectrum on the TLD response was studied by Monte Carlo simulations in present work. A sectional ART head phantom was used to be irradiated with the THOR BNCT beam. TLD-600 and TLD-700 chips were placed inside the phantom to measure and distinct the doses of neutrons from photons. Besides, dual TLD chips were placed in plane of the room space area to estimate the spatial dose distributions in the THOR BNCT treatment room. A cube water phantom was used to consider the deviation between the two algorithms used in this work. In the results, neutron and photon dose distributions in phantom and the spatial dose distributions in THOR BNCT treatment room were estimated; characteristics and the treatment indexes for BNCT were also assessed

  6. Design of epithermal neutron beam for clinical BNCT treatment at Slovenian TRIGA research reactor

    International Nuclear Information System (INIS)

    The Monte Carlo feasibility study of development of epithermal neutron beam for BNCT clinical trials on Jozef Stefan Institute (JSI) TRIGA reactor is presented. The investigation of the possible use of fission converter for the purpose of enhancement of neutron beam, as well as the set-up of TRIGA reactor core is performed. The optimization of the irradiation facility components is carried out and the configuration with the most favorable cost/performance ratio is proposed. The simulation results prove that a BNCT irradiation facility with performances, comparable to existing beams throughout the world, could be installed in the thermalizing column of the TRIGA reactor, quite suitable for the clinical treatments of human patients. (author)

  7. Design of epithermal neutron beam for clinical BNCT treatment at Slovenian TRIGA research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Maucec, Marko [Jozef Stefan Institute, Reactor Physics Division, Lubljana (Slovenia). E-mail: marko.mauce@ijs.si

    1999-07-01

    The Monte Carlo feasibility study of development of epithermal neutron beam for BNCT clinical trials on Jozef Stefan Institute (JSI) TRIGA reactor is presented. The investigation of the possible use of fission converter for the purpose of enhancement of neutron beam, as well as the set-up of TRIGA reactor core is performed. The optimization of the irradiation facility components is carried out and the configuration with the most favorable cost/performance ratio is proposed. The simulation results prove that a BNCT irradiation facility with performances, comparable to existing beams throughout the world, could be installed in the thermalizing column of the TRIGA reactor, quite suitable for the clinical treatments of human patients. (author)

  8. The relationship between boron neutron capture therapy (BNCT) and positron emission tomography (PET) for malignant brain tumors

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a particle irradiation therapy that is theoretically available for selective radiation of tumor cells. Boronophenylalanine-positron emission tomography (18F-BPA-PET) was used in this study. Boron is used as a tracer compound for the neutron capture reaction and has been particularly useful for the recent noncraniotomy BNCT. In this report, we introduce this type of PET as a principal axis in BNCT and relationship with PET. We calculated the drug accumulation to the tumor before neutron irradiation to individualize the treatment. We decided the indication for BNCT on the basis of a PET study and are now expanding the indications to other systemic cancers, including head and neck, lung, and liver cancers. In addition, other irradiation modalities have developed a radiation plan on the basis of a PET study, and several studies attempted improving the results; however, the lesion is exposed to high radiation doses and appear as high accumulation on BPA-PET during BNCT. We determined the neutron exposure time from the dosage for normal tissue in the actual treatment, but the lesion/normal tissue ratio obtained from BPA-PET is for evaluating the tumor dose and following the treatment plan. We also found that a PET study was useful in the follow-up stage to aid in diagnosis of pathologic conditions such as increase in tumor volume, recurrence, or radiation necrosis and for patients who had already been treated for malignant brain tumor. (author)

  9. The first main steps for development of BNCT neutron sources at the Ukrainian and Uzbek Research Reactors

    International Nuclear Information System (INIS)

    Both in Ukraine and in Uzbekistan, epithermal neutron irradiation facilities for Boron Neutron Capture Therapy (BNCT) are under consideration, as the need for them is very large. Based on information from medical cancer treatment institutions of the total number of patients identified with cancer, about 5000 have brain tumours. The most prospective method of their treatment is BNCT. Both in Ukraine and in Uzbekistan, this method can be implemented on existing research reactors. Modification of research reactors may be a relatively straightforward and inexpensive way to develop a BNCT neutron source, especially in comparison with construction of new reactors specialized for BNCT. However, prior to any reactor modification, careful calculations need to be performed, which take into account all the peculiarities of the specific reactor system. Based on the world experience in epithermal neutron beam development, it is very clear that the research reactors in Kyiv (Kyiv Research Reactor-KRR) and Tashkent (Tashkent Research Reactor-TRR) may be reconstructed into epithermal irradiation facilities. Selection of the most suitable materials for moderator, collimator, shielding, etc., demands carrying out calculations considering their individual characteristics. Since the KRR and TRR are the same kind of research reactors, with for example similar thermal columns, the development of a BNCT neutron source at these research reactors may be achieved in a like manner. The development plan and the first experience in this direction (using preliminary MCNP calculation results) are presented here. (author)

  10. Gamma dose measurement in a water phantom irradiated with the BNCT facility at THOR

    International Nuclear Information System (INIS)

    It has been proposed that a LiF thermoluminescence dosemeter (TLD) is used as a gamma dosemeter in a water phantom irradiated with the BNCT facility at THOR. Based on the TLD neutron sensitivity and neutron fluxes in the water phantom, which were simulated by the MCNP code. TLD-700 was chosen as a gamma dosemeter in this report. For the correction of the neutron influence on TLD-700, the thermal neutron sensitivity to TLD-700 was investigated with MCNP simulation and the thermal neutron flux was measured with gold foils using the cadmium difference technique. The correction to the neutron influence on the TLD was established on the TLD thermal neutron sensitivity, the thermal neutron flux, and the conversion factor from energy deposition in the TLD to the TLD response. By comparing the experimental data with the thermal neutron influence correction, these data are in very good agreement with the MCNP predictions. (author)

  11. Determination of the irradiation field at the research reactor TRIGA Mainz for BNCT.

    Science.gov (United States)

    Nagels, S; Hampel, G; Kratz, J V; Aguilar, A L; Minouchehr, S; Otto, G; Schmidberger, H; Schütz, C; Vogtländer, L; Wortmann, B

    2009-07-01

    For the application of the BNCT for the excorporal treatment of organs at the TRIGA Mainz, the basic characteristics of the radiation field in the thermal column as beam geometry, neutron and gamma ray energies, angular distributions, neutron flux, as well as absorbed gamma and neutron doses must be determined in a reproducible way. To determine the mixed irradiation field thermoluminescence detectors (TLD) made of CaF(2):Tm with a newly developed energy-compensation filter system and LiF:Mg,Ti materials with different (6)Li concentrations and different thicknesses as well as thin gold foils were used. PMID:19380234

  12. A preclinical study of boron neutron capture therapy (BNCT) of spontaneous tumors in cats at RA-6 in Argentina

    International Nuclear Information System (INIS)

    BNCT is a binary treatment modality that combines irradiation with a thermal or epithermal neutron beam with tumor-seeking, boron containing drugs to produce selective irradiation of tumor tissue. Having demonstrated that BNCT mediated by boronophenylalanine (BPA) induced control of experimental squamous cell carcinomas (SCC) of the hamster cheek pouch mucosa with no damage to normal tissue we explored the feasibility and safety of treating spontaneous head and neck tumors, with particular focus on SCC, of terminal feline patients with low dose BPA-BNCT employing the thermal beam of RA-1. Having demonstrated partial tumor control with no radio toxic effects, the aim of the present study was to evaluate the effect of BPA-BNCT on tumor and normal tissue in 3 cases of spontaneous SCC in feline patients employing a higher neutron fluence than in the previous study. The present study was performed at RA-6 with the thermalized epithermal neutron beam. All three irradiations were successful. Except for an initial, moderate and reversible mucositis, no significant radio toxic effects were observed in terms of clinical follow-up, histological examination, biochemical analysis and assessment of autopsy material. Partial tumor control was evidenced in terms of growth inhibition and partial necrosis and improvement in the quality of life during the survival period. Optimization of the therapeutic efficacy of BNCT would require improvement in boron tumor targeting and strategies to increase in-depth dose in large tumors. (author)

  13. Synthesis and evaluation of boron folates for Boron-Neutron-Capture-Therapy (BNCT)

    Energy Technology Data Exchange (ETDEWEB)

    Kettenbach, Kathrin; Schieferstein, Hanno; Grunewald, Catrin; Hampel, Gabriele; Schuetz, Christian L. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Iffland, Dorothee; Bings, Nicolas H. [Mainz Univ. (Germany). Inst. of Inorganic Chemistry and Analytical Chemistry; Reffert, Laura M. [Hannover Medical School (Germany). Radiopharmaceutical Chemistry; Ross, Tobias L. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Hannover Medical School (Germany). Radiopharmaceutical Chemistry

    2015-07-01

    Boron neutron capture therapy (BNCT) employs {sup 10}B-pharmaceuticals administered for the treatment of malignancies, and subsequently irradiated with thermal neutrons. So far, clinical established pharmaceuticals like boron phenylalanine (BPA) or sodium boron mercaptate (BSH) use imperfect (BPA) or passive (BSH) targeting for accumulation at target sites. Due to the need of a selective transportation of boron drugs into cancer cells and sparing healthy tissues, we combined the BNCT approach with the specific and effective folate receptor (FR) targeting concept. The FR is overexpressed on many human carcinomas and provides a selective and specific target for molecular imaging as well as for tumor therapy. We synthesized and characterized a carborane-folate as well as a BSH-folate to study their in vitro characteristics and their potential as new boron-carriers for BNCT. Uptake studies were carried out using human KB cells showing a significant increase of the boron content in cells and demonstrating the successful combination of active FR-targeting and BNCT.

  14. Spectrum shaping of accelerator-based neutron beams for BNCT

    CERN Document Server

    Montagnini, B; Esposito, J; Giusti, V; Mattioda, F; Varone, R

    2002-01-01

    We describe Monte Carlo simulations of three facilities for the production of epithermal neutrons for Boron Neutron Capture Therapy (BNCT) and examine general aspects and problems of designing the spectrum-shaping assemblies to be used with these neutron sources. The first facility is based on an accelerator-driven low-power subcritical reactor, operating as a neutron amplifier. The other two facilities have no amplifier and rely entirely on their primary sources, a D-T fusion reaction device and a conventional 2.5 MeV proton accelerator with a Li target, respectively.

  15. Medical set-up of boron neutron capture therapy (BNCT) for malignant glioma at the Japan research reactor (JRR)-4

    International Nuclear Information System (INIS)

    The University of Tsukuba project for boron neutron capture therapy (BNCT) was initiated at the Japan Atomic Energy Research Institute (JAERI) in 1992. The clinical study for BNCT began at the Japan Research Reactor (JRR)-2 of the JAERI in November 1995. By the end of 1998, a new medical irradiation facility had been installed in JRR-4 of that included a new medical treatment room and patient-monitoring area adjacent to the irradiation room. The medical treatment room was built to reflect a hospital-type operation room that includes an operating table with a carbon head frame, anesthesia apparatus with several cardiopulmonary monitors, etc. Following craniotomy in the treatment room, a patient under anesthesia is transported into the irradiation room for BNCT. The boron concentration in tissue is measured with prompt gamma ray analysis (PGA) and simultaneously by inductively coupled plasma atomic emission spectroscopy (ICP-AES) methods. For the immediate pre- and post-BNCT care, a collaborating neurosurgical department of the University of Tsukuba was prepared in the vicinity of the JAERI. The long term follow-up is done at the University of Tsukuba Hospital. Epithermal neutron beam also became available at the new JRR-4. By changing the thickness and/or the configuration of heavy water, a cadmium plate, and a graphite reflector, the JRR-4 provides a variety of neutron beams, including three typical beams (Epithermal mode and Thermal modes I and II). Intraoperative BNCT using the thermal beam is planned to study at the beginning of the clinical trial. The ongoing development of the JAERI Computational Dosimetry System (JCDS) and radiobiological studies have focused in the application of the epithermal beam for BNCT. After obtaining these basic data, we are planning to use the epithermal beam for intraoperative BNCT. (author)

  16. The multifunction neutron irradiator (MNI)

    Energy Technology Data Exchange (ETDEWEB)

    Yongmao Zhou; Shenzhi Li

    1994-12-31

    The Multifunction Neutron Irradiator (MNI) under design is a small-type neutron source reactor, for studying the Boron Neutron Capture Therapy (BNCT) for human brain glioblastoma and other uses in neutron technology such as Instrumental Neutron Activation Analysis (INAA), short-lived radioistope production, and some fundamental researches. The reactor core is designed to have passive safety and the process control of the reactor operations is fully computerized. There are two operational modes: The routine operation mode with reactor power 20{approximately}30 kW and flux 1 X 10{sup 12} n {center_dot} cm{sup -2} {center_dot} {sup -1} and the enhanced power operation mode for medical irradiation. The irradiator can be located in a medical center, research institute or university.

  17. Postoperative treatment of glioblastoma with BNCT at the Petten Irradiation Facility (EORTC Protocol 11961)

    International Nuclear Information System (INIS)

    The boron neutron capture therapy is based on the reaction occurring between the isotope 10B and thermal neutrons. A low energy neutron is captured by the nucleus and it disintegrates into two densely ionising particles, Li nucleus and He nucleus (α particle), with high biological effectiveness. On the basis of comprehensive preclinical investigations in the frame of the European Collaboration with Na2B12H11SH (BSH), as boron delivery agent, the first European phase I, clinical trial was designed at the only available epithermal beam in Europe, at the High Flux Reactor, Petten, in the Netherland. The goal of this study is to establish the safe BNCT dose for cranial tumors under defined conditions. BNCT is applied as postoperative radiotherapy in 4 fractions, after removal of the tumor for a group of patients suffering from glioblastoma, who would have no benefit from conventional treatment, but have sufficient life expectancy to detect late radiation morbidity due to BNCT. The starting dose is set at 80% of the dose where neurological effects occured in preclinical large animal experiments following a single fraction. The radiation dose will be escalated, by constant boron concentration in blood, in 4 steps for cohorts of ten patients, after an observation period of at least 6 months after the end of BNCT of the last patient of a cohort. The adverse events on healthy tissues due to BSH and due to the radiotherapy will be analysed in order to establish the maximal tolerated dose and dose limiting toxicity. Besides of the primary aim of this study the survival will be recorded. The first patient was treated in October 1997, and further four patients have been irradiated to date. The protocol design proved to be well applicable, establishing the basis for scientific evaluation, for performance of safe patient treatment in a very complex situation and for opening the possibility to perform further clinical research work on BNCT. (orig.)

  18. Comparison of the radiobiological effects of Boron neutron capture therapy (BNCT) and conventional Gamma Radiation

    International Nuclear Information System (INIS)

    BNCT is an experimental radiotherapeutic modality that uses the capacity of the isotope 10B to capture thermal neutrons leading to the production of 4He and 7Li, particles with high linear energy transfer (LET). The aim was to evaluate and compare in vitro the mechanisms of response to the radiation arising of BNCT and conventional gamma therapy. We measured the survival cell fraction as a function of the total physical dose and analyzed the expression of p27/Kip1 and p53 by Western blotting in cells of colon cancer (ARO81-1). Exponentially growing cells were distributed into the following groups: 1) BPA (10 ppm 10B) + neutrons; 2) BOPP (10 ppm 10B) + neutrons; 3) neutrons alone; 4) gamma-rays. A control group without irradiation for each treatment was added. The cells were irradiated in the thermal neutron beam of the RA-3 (flux= 7.5 109 n/cm2 sec) or with 60Co (1Gy/min) during different times in order to obtain total physical dose between 1-5 Gy (±10 %). A decrease in the survival fraction as a function of the physical dose was observed for all the treatments. We also observed that neutrons and neutrons + BOPP did not differ significantly and that BPA was the more effective compound. Protein extracts of irradiated cells (3Gy) were isolated to 24 h and 48 h post radiation exposure. The irradiation with neutrons in presence of 10BPA or 10BOPP produced an increase of p53 at 24 h maintain until 48 h. On the contrary, in the groups irradiated with neutrons alone or gamma the peak was observed at 48 hr. The level of expression of p27/Kip1 showed a reduction of this protein in all the groups irradiated with neutrons (neutrons alone or neutrons plus boron compound), being more marked at 24 h. These preliminary results suggest different radiobiological response for high and low let radiation. Future studies will permit establish the role of cell cycle in the tumor radio sensibility to BNCT. (author)

  19. FIR 1 reactor in service for boron neutron capture therapy (BNCT) and isotope production

    International Nuclear Information System (INIS)

    Full text: The FIR 1-reactor, a 250 kW Triga reactor, has been in operation since 1962. The main purpose for the existence of the reactor is now the Boron Neutron Capture Therapy (BNCT). The BNCT work dominates the current utilization of the reactor: three or four days per week are reserved for BNCT purposes and the rest for other purposes such as isotope production and neutron activation analysis. In the 1990's a BNCT treatment facility was build at the FiR1 reactor located at Technical Research Centre of Finland. A special new neutron moderator material FluentalTM (Al+AlF3+Li) developed at VTT ensures the superior quality of the neutron beam. Also the treatment environment is of world top quality. The ground floor of the reactor hall was provided with a new entrance, easily accessible by any patient vehicle, a radio therapy control room and rooms for patient preparation and laboratories. The top of the reactor tank was separated from the reactor hall in order to confine contamination in case of a leakage from irradiation samples or fuel elements. The ventilation of the building, emergency power supply system, heat exchangers and the secondary cooling circuit of the reactor including cooling towers were completely redesigned and rebuilt. The expenditure of designing and accomplishing the construction work described was about 4 million euros. The costs were partly financed with venture capital via Radtek Ltd., particularly established for this enterprise. Close to thirty patients have been treated at FiR 1 since May 1999, when the license for patient treatment was granted to the responsible BNCT treatment organization, Boneca Corporation. VTT as the reactor operator has a long term contract with the Boneca Corp. to provide the facility and irradiation services for the patient treatments. The BNCT facility has been licensed for clinical use and is being surveyed by several national public health authorities including the Finnish Nuclear and Radiation Safety

  20. “Sequential” Boron Neutron Capture Therapy (BNCT): A Novel Approach to BNCT for the Treatment of Oral Cancer in the Hamster Cheek Pouch Model

    Energy Technology Data Exchange (ETDEWEB)

    Ana J. Molinari; Emiliano C. C. Pozzi; Andrea Monti Hughes; Elisa M. Heber; Marcela A. Garabalino; Silvia I. Thorp; Marcelo Miller; Maria E. Itoiz; Romina F. Aromando; David W. Nigg; Jorge Quintana; Gustavo A. Santa Cruz; Veronica A. Trivillin; Amanda E. Schwint

    2011-04-01

    In the present study we evaluated the therapeutic effect and/or potential radiotoxicity of the novel “Tandem” Boron Neutron Capture Therapy (T-BNCT) for the treatment of oral cancer in the hamster cheek pouch model at RA-3 Nuclear Reactor. Two groups of animals were treated with “Tandem BNCT”, i.e. BNCT mediated by boronophenylalanine (BPA) followed by BNCT mediated by sodium decahydrodecaborate (GB-10) either 24 h (T-24h-BNCT) or 48 h (T-48h-BNCT) later. A total tumor dose-matched single application of BNCT mediated by BPA and GB-10 administered jointly [(BPA + GB-10)-BNCT] was administered to an additional group of animals. At 28 days post-treatment, T-24h-BNCT and T-48h-BNCT induced, respectively, overall tumor control (OTC) of 95% and 91%, with no statistically significant differences between protocols. Tumor response for the single application of (BPA + GB-10)-BNCT was 75%, significantly lower than for T-BNCT. The T-BNCT protocols and (BPA + GB-10)-BNCT induced reversible mucositis in dose-limiting precancerous tissue around treated tumors, reaching Grade 3/4 mucositis in 47% and 60% of the animals respectively. No normal tissue radiotoxicity was associated to tumor control for any of the protocols. “Tandem” BNCT enhances tumor control in oral cancer and reduces or, at worst, does not increase, mucositis in dose-limiting precancerous tissue.

  1. On-line neutron monitoring system of epithermal neutron beam for BNCT at THOR

    International Nuclear Information System (INIS)

    This paper aims to introduce the on-line neutron monitoring system (NMS) of epithermal neutron beam for BNCT at THOR and following tests. The NMS consists of three miniature fission chambers (Centronic, FC4A) and one gamma-ray monitor. The data acquisition and display are controlled by an in-house graphical user interface program. Both the real-time counting rates and the accumulated counts will be displayed simultaneously during irradiation. When the accumulated count reaches a preset value, the NMS will send a signal to the reactor operator to shut down the reactor. Examinations have been performed to demonstrate the system's reliability and linearity for desired reactor power range. The neutron counting rates were calibrated to the reaction rate of the gold foil measured free-in-air at the beam outlet center. By using the on-line NMS, an unstable fluctuation and long-term depression of epithermal neutron beam intensity was observed. It is suggested to normalize each performed irradiation by the average reading of the NMS. (author)

  2. Demonstration of the importance of a dedicated neutron beam monitoring system for BNCT facility.

    Science.gov (United States)

    Chao, Der-Sheng; Liu, Yuan-Hao; Jiang, Shiang-Huei

    2016-01-01

    The neutron beam monitoring system is indispensable to BNCT facility in order to achieve an accurate patient dose delivery. The neutron beam monitoring of a reactor-based BNCT (RB-BNCT) facility can be implemented through the instrumentation and control system of a reactor provided that the reactor power level remains constant during reactor operation. However, since the neutron flux in reactor core is highly correlative to complicated reactor kinetics resulting from such as fuel depletion, poison production, and control blade movement, some extent of variation may occur in the spatial distribution of neutron flux in reactor core. Therefore, a dedicated neutron beam monitoring system is needed to be installed in the vicinity of the beam path close to the beam exit of the RB-BNCT facility, where it can measure the BNCT beam intensity as closely as possible and be free from the influence of the objects present around the beam exit. In this study, in order to demonstrate the importance of a dedicated BNCT neutron beam monitoring system, the signals originating from the two in-core neutron detectors installed at THOR were extracted and compared with the three dedicated neutron beam monitors of the THOR BNCT facility. The correlation of the readings between the in-core neutron detectors and the BNCT neutron beam monitors was established to evaluate the improvable quality of the beam intensity measurement inferred by the in-core neutron detectors. In 29 sampled intervals within 16 days of measurement, the fluctuations in the mean value of the normalized ratios between readings of the three BNCT neutron beam monitors lay within 0.2%. However, the normalized ratios of readings of the two in-core neutron detectors to one of the BNCT neutron beam monitors show great fluctuations of 5.9% and 17.5%, respectively. PMID:26595774

  3. Upgrading of JRR-3/JRR-4 neutron beam utilities - for cold neutron beam and BNCT

    International Nuclear Information System (INIS)

    We proposed two plans to promote the medical application of nuclear energy in Japan. One is the enhancement of the cold neutron beam intensity for Japan Research Reactor No.3 (JRR-3) and the other one is the progress of Boron Neutron Capture Therapy (BNCT) for JRR-4. We are expecting to achieve 10 times the present intensity in our maximum extent so that the good complementary relation with J-PARC (Japan Proton Accelerator Complex) in one site can be established with JRR-3. More specifically the optimization of the cold neutron source vessel could increase the cold neutron beam intensity twice and the replacement of neutron guides with high efficiency mirror could increase it twice. Although BNCT in JRR-4 has been mainly applied to therapy against brain tumor so far, technical developments such as the development of a new collimator has enabled us to apply BNCT to head and neck cancer

  4. Neutron collimator design of neutron radiography based on the BNCT facility

    OpenAIRE

    Yang, XP.; Yu, BX; Li, YG; Peng, D; Lu, J.; Zhang, GL.; Zhao, H.; Zhang, AW.; Li, CY.; Liu, WJ; Hu, T.; Lv, JG.

    2013-01-01

    For the research of CCD neutron radiography, a neutron collimator was designed based on the exit of thermal neutron of the Boron Neutron Capture Therapy (BNCT) reactor. Based on the Geant4 simulations, the preliminary choice of the size of the collimator was determined. The materials were selected according to the literature data. Then, a collimator was constructed and tested on site. The results of experiment and simulation show that the thermal neutron flux at the end of theneutron collimat...

  5. Program for BNCT with accelerator-produced keV neutrons and related chemical and biological studies

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT), with slow neutrons, is based on the large cross-section of the stable boron isotope, 10B, for the thermal neutron capture. Upon capture of a neutron, the 10B nucleus is transformed to a highly excited 11B compound nucleus that promptly disintegrates into two antiparallel, highly energetic and cell-killing fragments, one 4He2+ and one 7Li3+ ion, with ranges of 9 and 5 micrometers, respectively. By more or less selective accumulation of 10B in suitable chemical form in or in close contact with the target cells, the probability of target cell sterilization is significantly increased, after therapeutic slow-neutron irradiation. This paper summarizes four different studies. They are: a spallation source for BNCT; boronation of EGF via dextran; synthesis of carboranes containing amino groups; and analysis of boron compounds with ICP-MS

  6. Development of a Tandem-ElectroStatic-Quadrupole accelerator facility for Boron Neutron Capture Therapy (BNCT)

    International Nuclear Information System (INIS)

    There is a generalized perception that the availability of suitable particle accelerators installed in hospitals, as neutron sources, may be crucial for the advancement of Boron Neutron Capture Therapy (BNCT). An ongoing project to develop a Tandem-ElectroStatic-Quadrupole (TESQ) accelerator facility for Accelerator-Based (AB)-BNCT is described here. The project goal is a machine capable of delivering 30 mA of 2.4-2.5 MeV protons to be used in conjunction with a neutron production target based on the 7Li(p,n)7Be reaction slightly beyond its resonance at 2.25 MeV. A folded tandem, with 1.20-1.25 MV terminal voltage, combined with an ESQ chain is being designed and constructed. This machine is conceptually shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the 7Li(p,n)7Be reaction, to perform BNCT treatment for deep-seated tumors in less than an hour. This electrostatic machine is one of the technologically simplest and cheapest solutions for optimized AB-BNCT. At present there is no BNCT facility in the world with the characteristics presented in this work. For the accelerator, results on its design, construction and beam transport calculations are discussed. Taking into account the peculiarities of the expected irradiation field, the project also considers a specific study of the treatment room. This study aims at the design of the treatment room emphasizing aspects related to patient, personnel and public radiation protection; dose monitoring; patient positioning and room construction. The design considers both thermal (for the treatment of shallow tumors) and epithermal (for deep-seated tumors) neutron beams entering the room through a port connected to the accelerator via a moderation and neutron beam shaping assembly. Preliminary results of dose calculations for the treatment room design, using the MCNP program, are presented

  7. 'Sequential' Boron Neutron Capture Therapy (BNCT): A Novel Approach to BNCT for the Treatment of Oral Cancer in the Hamster Cheek Pouch Model

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy (BNCT) is a binary treatment modality that involves the selective accumulation of 10B carriers in tumors followed by irradiation with a thermal or epithermal neutron beam. The minor abundance stable isotope of boron, 10B, interacts with low energy (thermal) neutrons to produce high linear energy transfer (LET) a-particles and 7Li ions. These disintegration products are known to have a high relative biological effectiveness (RBE). Their short range (<10 (micro)m) would limit the damage to cells containing 10B (1,2). Thus, BNCT would target tumor tissue selectively, sparing normal tissue. Clinical trials of BNCT for the treatment of glioblastoma multiforme and/or melanoma and, more recently, head and neck tumors and liver metastases, using boronophenylalanine (BPA) or sodium mercaptoundecahydrododecaborane (BSH) as the 10B carriers, have been performed or are underway in Argentina, Japan, the US and Europe (e.g. 3-8). To date, the clinical results have shown a potential, albeit inconclusive, therapeutic advantage for this technique. Contributory translational studies have been carried out employing a variety of experimental models based on the implantation of tumor cells in normal tissue (e.g. 5).

  8. "Sequential” Boron Neutron Capture Therapy (BNCT): A Novel Approach to BNCT for the Treatment of Oral Cancer in the Hamster Cheek Pouch Model

    Energy Technology Data Exchange (ETDEWEB)

    Ana J. Molinari; Andrea Monti Hughes; Elisa M. Heber; Marcela A. Garabalino; Veronica A. Trivillin; Amanda E. Schwint; Emiliano C. C. Pozzi; Maria E. Itoiz; Silvia I. Thorp; Romina F. Aromando; David W. Nigg; Jorge Quintana; Gustavo A. Santa Cruz

    2011-04-01

    Boron Neutron Capture Therapy (BNCT) is a binary treatment modality that involves the selective accumulation of 10B carriers in tumors followed by irradiation with a thermal or epithermal neutron beam. The minor abundance stable isotope of boron, 10B, interacts with low energy (thermal) neutrons to produce high linear energy transfer (LET) a-particles and 7Li ions. These disintegration products are known to have a high relative biological effectiveness (RBE). Their short range (<10 {micro}m) would limit the damage to cells containing 10B (1,2). Thus, BNCT would target tumor tissue selectively, sparing normal tissue. Clinical trials of BNCT for the treatment of glioblastoma multiforme and/or melanoma and, more recently, head and neck tumors and liver metastases, using boronophenylalanine (BPA) or sodium mercaptoundecahydrododecaborane (BSH) as the 10B carriers, have been performed or are underway in Argentina, Japan, the US and Europe (e.g. 3-8). To date, the clinical results have shown a potential, albeit inconclusive, therapeutic advantage for this technique. Contributory translational studies have been carried out employing a variety of experimental models based on the implantation of tumor cells in normal tissue (e.g. 5).

  9. Characteristics of the new THOR epithermal neutron beam for BNCT

    International Nuclear Information System (INIS)

    A characterization of the new Tsing Hua open-pool reactor (THOR) epithermal neutron beam designed for boron neutron capture therapy (BNCT) has been performed. The facility is currently under construction and expected in completion in March 2004. The designed epithermal neutron flux for 1 MW power is 1.7x109 n cm-2 s-1 in air at the beam exit, accompanied by photon and fast neutron absorbed dose rates of 0.21 and 0.47 mGy s-1, respectively. With 10B concentrations in normal tissue and tumor of 11.4 and 40 ppm, the calculated advantage depth dose rate to the modified Snyder head phantom is 0.53 RBE-Gy min-1 at the advantage depth of 85 mm, giving an advantage ratio of 4.8. The dose patterns determined by the NCTPlan treatment planning system using the new THOR beam for a patient treated in the Harvard-MIT clinical trial were compared with results of the MITR-II M67 beam. The present study confirms the suitability of the new THOR beam for possible BNCT clinical trials

  10. Characteristics of neutron irradiation facility and dose estimation method for neutron capture therapy at Kyoto University research reactor institute

    International Nuclear Information System (INIS)

    The neutron irradiation characteristics of the Heavy Water Neutron Irradiation Facility (HWNIF) at the Kyoto University Research Reactor Institute (KIJRRI) for boron neutron capture therapy (BNCT), is described. The present method of dose measurement and its evaluation at the KURRI, is explained. Especially, the special feature and noticeable matters were expounded for the BNCT with craniotomy, which has been applied at present only in Japan. (author)

  11. High neutron flux quality for irradiation and BCNT conditions

    International Nuclear Information System (INIS)

    This paper presents methods for characterising the neutron field in irradiation and boron neutron capture therapy (BNCT) facilities, applications for which a high flux quality is needed. The irradiation facility considered consists of an isotopic (Am-Be) neutron source in a cylindrical cavity bored inside a solid paraffin cube measuring 51·51·51 cm, thus constituting a neutron Howitzer. The neutron flux distribution within the cavity above this source was investigated by measurements of aluminium foil activation and by calculations with the MCNP-4C code. The BNCT calculations were performed for different channel radii. Results from measurements and calculations are in good agreement despite the uncertainties in identifying the exact energies at which the two reactions measured, 27Al(n,γ)28Al and 27Al(n, p)27Mg, take place. The study provided useful information about the optimal irradiation and BNCT conditions. (author)

  12. Neutron field characterization in the installation for BNCT study in the IEA-R1 reactor; Caracterizacao do campo de neutrons na instalacao para estudo em BNCT no reator IEA-R1

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro Junior, Valdeci

    2008-07-01

    This work aims to characterize the mixed neutron and gamma field, in the sample irradiation position, in a research installation for Boron Neutron Capture Therapy (BNCT), in the IPEN IEA-R1 reactor. The BNCT technique has been studied as a safe and selective option in the treatment of resistant cancerigenous tumors or considered non-curable by the conventional techniques, for example, the Glioblastoma Multiform - a brain cancerigenous tumor. Neutron flux measurements were carried out: thermal, resonance and fast, as well as neutron and gamma rays doses, in the sample position, using activation foils detectors and thermoluminescent dosimeters. For the determination of the neutron spectrum and intensity, a set of different threshold activation foils and gold foils covered and uncovered with cadmium irradiated in the installation was used, analyzed by a high Pure Germanium semiconductor detector, coupled to an electronic system suitable for gamma spectrometry. The results were processed with the SAND-BP code. The doses due to gamma and neutron rays were determined using thermoluminescent dosimeters TLD 400 and TLD 700 sensitive to gamma and TLD 600, sensitive to neutrons. The TLDs were selected and used for obtaining the calibration curves - dosimeter answer versus dose - from each of the TLD three types, which were necessary to calculate the doses due to neutron and gamma, in the sample position. The radiation field, in the sample irradiation position, was characterized flux for thermal neutrons of 1.39.10{sup 8} {+-} 0,12.10{sup 8} n/cm{sup 2}s the doses due to thermal neutrons are three times higher than those due to gamma radiation and confirm the reproducibility and consistency of the experimental findings obtained. Considering these results, the neutron field and gamma radiation showed to be appropriated for research in BNCT. (author)

  13. Current development at the Finnish TRIGA reactor towards the operation of the new BNCT irradiation facility

    International Nuclear Information System (INIS)

    The FiR 1-reactor, a 250 kW Triga reactor, with its subsystems has experienced a large renovation work. The main purpose of the upgrading has been to install the new Boron Neutron Capture Therapy (BNCT) irradiation facility. During the renovation the ventilation, electricity lines, water and waste water pipe lines and the reactor cooling system were renewed. The epithermal beam facility of the BNCT-irradiation station got its final form. In order to increase the availability of the reactor and the necessary systems in the reactor building all the pumps of the reactor cooling system and the main fans of the ventilation have been doubled. The reactor instrumentation is fed by an Uninterruptible Power System and a diesel aggregate feeds power to the reactor cooling and the ventilation systems, if the normal power supply fails. The epithermal neutrons are produced from the fast fission neutrons by a moderator block consisting of Al+AIF3 (FLUENTALTM), Which showed to be the optimum material for this purpose. Independently of the large renovation work the application for a new operating license for the reactor had to be submitted at the end of the year 1998 after nine years' operating time With the old license. (author)

  14. Towards in vivo monitoring of neutron distributions for quality control of BNCT

    Science.gov (United States)

    Verbakel, W. F. A. R.; Hideghety, K.; Morrissey, J.; Sauerwein, W.; Stecher-Rasmussen, F.

    2002-04-01

    Dose delivery in boron neutron capture therapy (BNCT) is complex because several components contribute to the dose absorbed in tissue. This dose is largely determined by local boron concentration, thermal neutron distribution and patient positioning. In vivo measurements of these factors would considerably improve quality control and safety. During therapy, a γ-ray telescope measures the γ-rays emitted following neutron capture by hydrogen and boron in a small volume of the head of a patient. Scans of hydrogen γ-ray emissions could be used to verify the actual distribution of thermal neutrons during neutron irradiation. The method was first tested on different phantoms. These measurements showed good agreement with calculations based on thermal neutron distributions derived from a treatment planning program and from Monte Carlo N-particle (MCNP) simulations. Next, the feasibility of telescope scans during patient irradiation therapy was demonstrated. Measurements were reproducible between irradiation fractions. In theory, this method can be used to verify the positioning of the patient in vivo and the delivery of thermal neutrons in tissue. However, differences between measurements and calculations based on a routine treatment planning program were observed. These differences could be used to refine the treatment planning. Further developments will be necessary for this method to become a standard quality control system.

  15. Dosimetric analysis of BNCT - Boron Neutron Capture Therapy - coupled to 252Cf brachytherapy

    International Nuclear Information System (INIS)

    The incidence of brain tumors is increasing in world population; however, the treatments employed in this type of tumor have a high rate of failure and in some cases have been considered palliative, depending on histology and staging of tumor. Its necessary to achieve the control tumor dose without the spread irradiation cause damage in the brain, affecting patient neurological function. Stereotactic radiosurgery is a technique that achieves this; nevertheless, other techniques that can be used on the brain tumor control must be developed, in order to guarantee lower dose on health surroundings tissues other techniques must be developing. The 252Cf brachytherapy applied to brain tumors has already been suggested, showing promising results in comparison to photon source, since the active source is placed into the tumor, providing greater dose deposition, while more distant regions are spared. BNCT - Boron Neutron Capture Therapy - is another technique that is in developing to brain tumors control, showing theoretical superiority on the rules of conventional treatments, due to a selective irradiation of neoplasics cells, after the patient receives a borate compound infusion and be subjected to a epithermal neutrons beam. This work presents dosimetric studies of the coupling techniques: BNCT with 252Cf brachytherapy, conducted through computer simulation in MCNP5 code, using a precise and well discretized voxel model of human head, which was incorporated a representative Glioblastoma Multiform tumor. The dosimetric results from MCNP5 code were exported to SISCODES program, which generated isodose curves representing absorbed dose rate in the brain. Isodose curves, neutron fluency, and dose components from BNCT and 252Cf brachytherapy are presented in this paper. (author)

  16. Boron neutron capture therapy (BNCT) for glioblastoma multiforme using the epithermal neutron beam at the Brookhaven Medical Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Capala, J. [Brookhaven National Lab., Upton, NY (United States); Diaz, A.Z.; Chadha, M. [Univ. Hospital, State Univ. of New York, NY (United States)] [and others

    1997-12-31

    The abstract describes evaluation of boron neutron capture therapy (BNCT) for two groups of glioblastoma multiforme patients. From September 1994 to February 1996 15 patients have been treated. In September 1997 another 34 patients were examined. Authors determined a safe starting dose for BNCT using epithermal neutrons and BPA-F. They have also evaluated adverse effects of BNCT at this starting dose. Therapeutic effectiveness of this starting dose has been evaluated. No significant side effects from BPA-F infusion or BNCT treatment were observed in normal brains.

  17. Epithermal BNCT neutron beam design for a TRIGA II reactor

    International Nuclear Information System (INIS)

    In Finland a collaborative effort by Helsinki University Central Hospital, MAP Medical Technologies Inc. and VTT Reactor Laboratory has started aiming at BNCT of glioma patients. For this the capabilities of the FiR-1 TRIGA II 250 kW research reactor have been evaluated. The FiR-1 is located in the middle of the Otaniemi campus eight kilometers from the center of Helsinki and four kilometers from the Central Hospital. The power of the reactor was increased in 1965 to 250 kW and the instrumentation modernised in 1981. It is a pool reactor with graphite reflector and a core loading of 3 kg 20w% 235U in the special TRIGA uranium-zirconium hydride fuel (8-12 w% U, 91% Zr, 1% H). The advantages of using a TRIGA reactor for BNCT have already been pointed out earlier by Whittemore and have been verified in practice by the thermal neutron treatment work done at the Musashi 100 kW reactor. The advantages include a wide core face area and a wide spatial angle covered by the thermal-epithermal column system, large flux-per-Watt feature and inherent safety of the TRIGA fuel. Because of its wider applicability and less stringent requirements for clinical operation conditions, an epithermal neutron beam has been selected as the design goal. The epithermal flux should be sufficient for glioblastoma patient treatment: 109 epithermal neutrons/cm2/s with low enough fast neutron (-13Gy/epithermal n/cm2) and gamma contamination

  18. Boron Neutron Capture Therapy at the TRIGA Mark II of Pavia, Italy - The BNCT of the diffuse tumours

    Energy Technology Data Exchange (ETDEWEB)

    Altieri, S.; Bortolussi, S.; Stella, S.; Bruschi, P.; Gadan, M.A. [University of Pavia (Italy); INFN - National Institute for Nuclear Physics, of Pavia (Italy)

    2008-10-29

    The selectivity based on the B distribution rather than on the irradiation field makes Boron neutron Capture Therapy (BNCT) a valid option for the treatment of the disseminated tumours. As the range of the high LET particles is shorter than a cell diameter, the normal cells around the tumour are not damaged by the reactions occurring in the tumoral cells. PAVIA 2001: first treatment of multiple hepatic metastases from colon ca by BNCT and auto-transplantation technique: TAOrMINA project. The liver was extracted after BPA infusion, irradiated in the Thermal Column of the Pavia TRIGA Mark II reactor, and re-implanted in the patient. Two patients were treated, demonstrating the feasibility of the therapy and the efficacy in destroying the tumoral nodules sparing the healthy tissues. In the last years, the possibility of applying BNCT to the lung tumours using epithermal collimated neutron beams and without explanting the organ, is being explored. The principal obtained results of the BNCT research are presented, with particular emphasis on the following aspects: a) the project of a new thermal column configuration to make the thermal neutron flux more uniform inside the explanted liver, b) the Monte Carlo study by means of the MCNP code of the thermal neutron flux distribution inside a patient's thorax irradiated with epithermal neutrons, and c) the measurement of the boron concentration in tissues by (n,{alpha}) spectroscopy and neutron autoradiography. The dose distribution in the thorax are simulated using MCNP and the anthropomorphic model ADAM. To have a good thermal flux distribution inside the lung epithermal neutrons must be used, which thermalize crossing the first tissue layers. Thermal neutrons do not penetrate and the obtained uniformity is poor. In the future, the construction of a PGNAA facility using a horizontal channel of the TRIGA Mark II is planned. With this method the B concentration can be measured also in liquid samples (blood, urine) and

  19. Boron neutron capture therapy (BNCT) for glioblastoma multiforme (GBM), using the epithermal neutron beam at the Brookhaven National Laboratory

    International Nuclear Information System (INIS)

    Objective: BNCT is a binary treatment modality based on the nuclear reactions that occur when boron (10B) is exposed to thermal neutrons. Preclinical studies have demonstrated the therapeutic efficacy of p-boronophenylalanine (BPA)-based BNCT. The objective of the Phase I/II trial was to evaluate BPA-fructose (BPA-F) as a boron delivery agent for GBM and to study the feasibility and safety of a single-fraction of BNCT. Materials and Methods: The trial design required i) a BPA-F biodistribution study performed at the time of craniotomy; and ii) BNCT within 4 weeks of the craniotomy. From September 94 to July 95, 10 patients with biopsy proven GBM were treated. All but 1 patient underwent a biodistribution study receiving IV BPA-F at the time of craniotomy. Multiple tissue samples and concurrent blood and urine samples were collected for evaluation of the boron concentration and clearance kinetics. For BNCT all patients received 250 mg/kgm of BPA-F (IV infusion over 2 hrs) followed by neutron irradiation. The blood 10B concentration during irradiation was used to calculate the time of neutron exposure. The 3D treatment planning was done using the BNCT treatment planning software developed at the Idaho National Engineering Laboratory. The BNCT dose is expressed as the sum of the physical dose components corrected for both the RBE and the 10B localization factor with the unit Gy-Eq. The photon-equivalent dose, where the thermal neutron fluence reaches a maximum, is the peak-dose equivalent. A single-fraction of BNCT was delivered prescribing 10.5 Gy-Eq (9 patients) and 13.8 Gy-Eq (1 patient) as the peak dose-equivalent to the normal brain. The peak dose rate was kept below 27 cGy-Eq/min. Results: Biodistribution data: The maximum blood 10B concentration was observed at the end of the infusion and scaled as a linear function of the administered dose. The 10B concentration in the scalp and in the GBM tissue was higher than in blood by 1.5 x and at least 3.5 x

  20. Boron neutron capture therapy (BNCT) for liver metastasis in an experimental model: dose–response at five-week follow-up based on retrospective dose assessment in individual rats

    Energy Technology Data Exchange (ETDEWEB)

    Emiliano C. C. Pozzi; Veronica A. Trivilin; Lucas L. Colombo; Andrea Monti Hughes; Silvia I. Thorp; Jorge E. Cardoso; Marcel A. Garabalino; Ana J. Molinari; Elisa M. Heber; Paula Curotto; Marcelo Miller; Maria E. Itoiz; Romina F. Aromando; David W. Nigg; Amanda E. Schwint

    2013-11-01

    Boron neutron capture therapy (BNCT) was proposed for untreatable colorectal liver metastases. Employing an experimental model of liver metastases in rats, we recently demonstrated that BNCT mediated by boronophenylalanine (BPA-BNCT) at 13 Gy prescribed to tumor is therapeutically useful at 3-week follow-up. The aim of the present study was to evaluate dose–response at 5-week follow-up, based on retrospective dose assessment in individual rats. BDIX rats were inoculated with syngeneic colon cancer cells DHD/K12/TRb. Tumor-bearing animals were divided into three groups: BPA-BNCT (n = 19), Beam only (n = 8) and Sham (n = 7) (matched manipulation, no treatment). For each rat, neutron flux was measured in situ and boron content was measured in a pre-irradiation blood sample for retrospective individual dose assessment. For statistical analysis (ANOVA), individual data for the BPA-BNCT group were pooled according to absorbed tumor dose, BPA-BNCT I: 4.5–8.9 Gy and BPA-BNCT II: 9.2–16 Gy. At 5 weeks post-irradiation, the tumor surface area post-treatment/pre-treatment ratio was 12.2 +/- 6.6 for Sham, 7.8 +/- 4.1 for Beam only, 4.4 +/- 5.6 for BPA-BNCT I and 0.45 +/- 0.20 for BPA-BNCT II; tumor nodule weight was 750 +/- 480 mg for Sham, 960 +/- 620 mg for Beam only, 380 +/- 720 mg for BPA-BNCT I and 7.3 +/- 5.9 mg for BPA-BNCT II. The BPA-BNCT II group exhibited statistically significant tumor control with no contributory liver toxicity. Potential threshold doses for tumor response and significant tumor control were established at 6.1 and 9.2 Gy, respectively.

  1. Biodistribution of Boron compounds in an experimental model of liver metastases for Boron Neutron Capture (BNCT) Studies

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy (BNCT) is a binary treatment modality that involves the selective accumulation of 10B carriers in tumors followed by irradiation with thermal or epithermal neutrons. The high linear energy transfer alpha particles and recoiling 7Li nuclei emitted during the capture of a thermal neutron by a 10B nucleus have a short range and a high biological effectiveness. Thus, BNCT would potentially target neoplastic tissue selectively. In previous studies we demonstrated the therapeutic efficacy of different BNCT protocols in an experimental model of oral cancer. More recently we performed experimental studies in normal rat liver that evidenced the feasibility of treating liver metastases employing a novel BNCT protocol proposed by JEC based on ex-situ treatment and partial liver auto-transplant. The aim of the present study was to perform biodistribution studies with different boron compounds and different administration protocols to determine the protocols that would be therapeutically useful in 'in vivo' BNCT studies at the RA-3 Nuclear Reactor in an experimental model of liver metastases in rats. Materials and Methods. A total of 70 BDIX rats (Charles River Lab., MA, USA) were inoculated in the liver with syngeneic colon cancer cells DH/DK12/TRb (ECACC, UK) to induce the development of subcapsular metastatic nodules. 15 days post-inoculation the animals were used for biodistribution studies. A total of 11 protocols were evaluated employing the boron compounds boronophenylalanine (BPA) and GB-10 (Na210B1-0H10), alone or combined employing different doses and administration routes. Tumor, normal tissue and blood samples were processed for boron measurement by ICP-OES. Results. Several protocols proved potentially useful for BNCT studies in terms of absolute boron concentration in tumor and preferential uptake of boron by tumor tissue, i.e. BPA 15.5 mg 10B/kg iv + GB-10 50 mg 10B/kg iv; BPA 46.5 mg 10B/kg ip; BPA 46.5 mg 10B/kg ip + iv; BPA 46

  2. Radioprotective agents to reduce BNCT (Boron Neutron Capture Therapy) induced mucositis in the hamster cheek pouch

    International Nuclear Information System (INIS)

    Introduction: BNCT is based on the capture reaction between boron, selectively targeted to tumor tissue, and thermal neutrons which gives rise to lethal, short-range high linear energy transfer particles that selectively damage tumor tissue, sparing normal tissue. We previously evidenced a remarkable therapeutic success of BNCT mediated by boronophenylalanine (BPA) in the hamster cheek pouch oral cancer and pre cancer model. Despite therapeutic efficacy, mucositis induced in premalignant tissue was dose limiting and favored, in some cases, tumor development. In a clinical scenario, oral mucositis limits the dose administered to head and neck tumors. Aim: Our aim was to evaluate the effect of the administration of different radioprotective agents, seeking to reduce BNCT-induced mucositis to acceptable levels in dose-limiting premalignant tissue; without compromising therapeutic effect evaluated as inhibition on tumor development in premalignant tissue; without systemic or local side effects; and without negative effects on the biodistribution of the boron compound used for treatment. Materials and methods: Cancerized hamsters with DMBA (dimethylbenzanthracene) were treated with BPA-BNCT 5 Gy total absorbed dose to premalignant tissue, at the RA-3 Nuclear Reactor, divided into different groups: 1-treated with FLUNIXIN; 2- ATORVASTATIN; 3-THALIDOMIDE; 4-HISTAMINE (two concentrations: Low -1 mg/ml- and High -5 mg/ml-); 5-JNJ7777120; 6-JNJ10191584; 7-SALINE (vehicle). Cancerized animals without any treatment (neither BNCT nor radioprotective therapy) were also analyzed. We followed the animals during one month and evaluated the percentage of animals with unacceptable/severe mucositis, clinical status and percentage of animals with new tumors post treatment. We also performed a preliminary biodistribution study of BPA + Histamine “low” concentration to evaluate the potential effect of the radioprotector on BPA biodistribution. Results: Histamine

  3. The angular and spatial distributions of the thermal neutron source description of the THOR BNCT beam

    International Nuclear Information System (INIS)

    This paper presents a way to determine the angular and spatial distributions of the thermal neutron source strength of a boron neutron capture therapy (BNCT) beam. The experiments applied 1) the indirect neutron radiography, 2) the cadmium difference method, and 3) the instrumental neutron activation analysis. The measured data were processed by the spectrum deconvolution technique to resolve into a proper set of angular and spatial distributions. This paper took the epithermal neutron beam of the BNCT facility at the Tsing Hua Open-pool Reactor as an example.

  4. Experimental results analysis and simulation to evaluate flux and dose at the irradiation sample position of the BNCT research facility

    International Nuclear Information System (INIS)

    To study the BNCT (Boron Neutron Capture Therapy) researchers of the IPEN developed and constructed a facility in the IEA-R1 reactor from IPEN/CNEN-SP, using the beam hole number 3. This facility was constructed to perform experiments of radiation field characterization (neutrons and gammas) suitable to the application of the BNCT technique along with other kinds of experiments in several fields of physics and biology. The purpose of this work is to analyze experimental results, and the simulation to evaluate neutron flux and dose due to gamma radiation at the sample irradiation position of the facility. For the thermal and epithermal flux measurements, the cadmium rate technique with activation foil detector was used, and for the dose determination due to gamma radiation, thermo luminescent dosimeters were used. In the simulation part of this work, the computational transport code DOT 3.5 was utilized. With activation foil detector, a thermal neutron flux of 2.31.108 ± 0.03.108 n/cm2s, and for epithermal neutrons of 4.6.106 ± 0.1.106 n/cm2s were observed at the facility sample irradiation position. With thermoluminescent dosimeters, a dose rate for gamma radiation of 21 ± 1 Gy/h was observed at the sample irradiation position. The observed simulation results show agreement with those experimental flux measurements. (author)

  5. Spatial and spectral characteristics of a compact system neutron beam designed for BNCT facility

    International Nuclear Information System (INIS)

    The development of suitable neutron sources and neutron beam is critical to the success of Boron Neutron Capture Therapy (BNCT). In this work a compact system designed for BNCT is presented. The system consists of 252Cf fission neutron source and a moderator/reflector/filter/shield assembly. The moderator/reflector/filter arrangement has been optimized to maximize the epithermal neutron component which is useful for BNCT treatment of deep seated tumors with the suitably low level of beam contamination. The MCMP5 code has been used to calculate the different components of neutrons, secondary gamma rays originating from 252Cf source and the primary gamma rays emitted directly by this source at the exit face of the compact system. The fluence rate distributions of such particles were also computed along the central axis of a human head phantom

  6. Spatial and spectral characteristics of a compact system neutron beam designed for BNCT facility

    Energy Technology Data Exchange (ETDEWEB)

    Ghassoun, J. [EPRA, Departement de Physique, Faculte des Sciences Semlalia, B.P. 2390, 40000 Marrakech (Morocco)], E-mail: ghassoun@ucam.ac.ma; Chkillou, B.; Jehouani, A. [EPRA, Departement de Physique, Faculte des Sciences Semlalia, B.P. 2390, 40000 Marrakech (Morocco)

    2009-04-15

    The development of suitable neutron sources and neutron beam is critical to the success of Boron Neutron Capture Therapy (BNCT). In this work a compact system designed for BNCT is presented. The system consists of {sup 252}Cf fission neutron source and a moderator/reflector/filter/shield assembly. The moderator/reflector/filter arrangement has been optimized to maximize the epithermal neutron component which is useful for BNCT treatment of deep seated tumors with the suitably low level of beam contamination. The MCMP5 code has been used to calculate the different components of neutrons, secondary gamma rays originating from {sup 252}Cf source and the primary gamma rays emitted directly by this source at the exit face of the compact system. The fluence rate distributions of such particles were also computed along the central axis of a human head phantom.

  7. Spatial and spectral characteristics of a compact system neutron beam designed for BNCT facility.

    Science.gov (United States)

    Ghassoun, J; Chkillou, B; Jehouani, A

    2009-04-01

    The development of suitable neutron sources and neutron beam is critical to the success of Boron Neutron Capture Therapy (BNCT). In this work a compact system designed for BNCT is presented. The system consists of (252)Cf fission neutron source and a moderator/reflector/filter/shield assembly. The moderator/reflector/filter arrangement has been optimized to maximize the epithermal neutron component which is useful for BNCT treatment of deep seated tumors with the suitably low level of beam contamination. The MCMP5 code has been used to calculate the different components of neutrons, secondary gamma rays originating from (252)Cf source and the primary gamma rays emitted directly by this source at the exit face of the compact system. The fluence rate distributions of such particles were also computed along the central axis of a human head phantom. PMID:19168369

  8. Measurement of thermal neutron fluence rate of in-hospital neutron irradiator by SSNTD

    International Nuclear Information System (INIS)

    In-hospital neutron irradiator (IHNI) is an especially designed nuclear device based on Miniature Neutron Source Reactor (MNSR) for boron neutron capture therapy (BNCT). Its rated power is 30 kW. There are a thermal neutron beam and an epithermal neutron beam for treating patients at the opposite of the core. From the thermal neutron beam, a test beam is fetched out for measurement of boron concentration in blood by prompt γ neutron activation analysis (PGNAA) method. The neutron fluence rates at the end of thermal, epithermal and test neutron beam were measured by 235U fissile target and mica slice detector. At rated power, they are 1.67 × 109, 2.44 × 107 and 3.03 × 106 cm-2 · s-1, respectively. The results show that the thermal and epithermal neutron fluence rate can meet the requirement of BNCT and test neutron fluence rate meets the requirement of PGNAA. (authors)

  9. Neutron collimator design of neutron radiography based on the BNCT facility

    International Nuclear Information System (INIS)

    For the research of CCD neutron radiography, a neutron collimator was designed based on the exit of thermal neutron of the Boron Neutron Capture Therapy (BNCT) reactor. Based on the Geant4 simulations, the preliminary choice of the size of the collimator was determined. The materials were selected according to the literature data. Then, a collimator was constructed and tested on site. The results of experiment and simulation show that the thermal neutron flux at the end of the neutron collimator is greater than 1.0×106 n/cm2/s, the maximum collimation ratio (L/D) is 58, the Cd-ratio(Mn) is 160 and the diameter of collimator end is 10 cm. This neutron collimator is considered to be applicable for neutron radiography. (authors)

  10. Physical and biological dosimetry at the RA-3 facility for small animal irradiation: preliminary BNCT studies in an experimental model of oral cancer

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy (BNCT) is a binary treatment modality based on the capture reaction that occurs between thermal neutrons and boron-10 atoms that accumulate selectively in tumor tissue, emitting high linear energy transfer (LET), short range (5-9 microns) particles (alpha y 7Li). Thus, BNCT would potentially target tumor tissue selectively, sparing normal tissue. Herein we evaluated the feasibility of treating experimental oral mucosa tumors with BNCT at RA-3 (CAE) employing the hamster cheek pouch oral cancer model and characterized the irradiation field at the RA-3 facility. We evaluated the therapeutic effect on tumor of BNCT mediated by BPA in the hamster cheek pouch oral cancer model and the potential radio toxic effects in normal tissue. We evidenced a moderate biological response in tumor, with no radio toxic effects in normal tissue following irradiations with no shielding for the animal body. Given the sub-optimal therapeutic response, we designed and built a 6Li2CO3 shielding for the body of the animal to increase the irradiation dose to tumor, without exceeding normal tissue radio tolerance. The measured absolute magnitude of thermal neutron flux and the characterization of the beam with and without the shielding in place, suggest that the irradiation facility in the thermal column of RA-3 would afford an excellent platform to perform BNCT studies in vitro and in vivo in small experimental animals. The present findings must be confirmed and extended by performing in vivo BNCT radiobiological studies in small experimental animals, employing the shielding device for the animal body. (author)

  11. Correlation of clinical outcome to the estimated radiation dose from Boron Neutron Capture Therapy (BNCT)

    Energy Technology Data Exchange (ETDEWEB)

    Chadha, M. [Beth Israel Medical Center, NY (United States). Dept. of Radiation Oncology; Coderre, J.A.; Chanana, A.D. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1996-12-31

    A phase I/II trial delivering a single fraction of BNCT using p-Boronophenylalanine-Fructose and epithermal neutrons at the the Brookhaven Medical Research Reactor was initiated in September 1994. The primary endpiont of the study was to evaluate the feasibility and safety of a given BNCT dose. The clinical outcome of the disease was a secondary endpoint of the study. The objective of this paper is to evaluate the correlation of the clinical outcome of patients to the estimated radiation dose from BNCT.

  12. Correlation of clinical outcome to the estimated radiation dose from Boron Neutron Capture Therapy (BNCT)

    International Nuclear Information System (INIS)

    A phase I/II trial delivering a single fraction of BNCT using p-Boronophenylalanine-Fructose and epithermal neutrons at the the Brookhaven Medical Research Reactor was initiated in September 1994. The primary endpiont of the study was to evaluate the feasibility and safety of a given BNCT dose. The clinical outcome of the disease was a secondary endpoint of the study. The objective of this paper is to evaluate the correlation of the clinical outcome of patients to the estimated radiation dose from BNCT

  13. Characterisation of an accelerator-based neutron source for BNCT versus beam energy

    CERN Document Server

    Agosteo, S; D'Errico, F; Nath, R; Tinti, R

    2002-01-01

    Neutron capture in sup 1 sup 0 B produces energetic alpha particles that have a high linear energy transfer in tissue. This results in higher cell killing and a higher relative biological effectiveness compared to photons. Using suitably designed boron compounds which preferentially localize in cancerous cells instead of healthy tissues, boron neutron capture therapy (BNCT) has the potential of providing a higher tumor cure rate within minimal toxicity to normal tissues. This clinical approach requires a thermal neutron source, generally a nuclear reactor, with a fluence rate sufficient to deliver tumorcidal doses within a reasonable treatment time (minutes). Thermal neutrons do not penetrate deeply in tissue, therefore BNCT is limited to lesions which are either superficial or otherwise accessible. In this work, we investigate the feasibility of an accelerator-based thermal neutron source for the BNCT of skin melanomas. The source was designed via MCNP Monte Carlo simulations of the thermalization of a fast ...

  14. Neutron collimator design of neutron radiography based on the BNCT facility

    CERN Document Server

    Yang, XP; Li, YG; Peng, D; Lu, J; Zhang, GL; Zhao, H; Zhang, AW; Li, CY; Liu, WJ; Hu, T; Lv, JG

    2013-01-01

    For the research of CCD neutron radiography, a neutron collimator was designed based on the exit of thermal neutron of the Boron Neutron Capture Therapy (BNCT) reactor. Based on the Geant4 simulations, the preliminary choice of the size of the collimator was determined. The materials were selected according to the literature data. Then, a collimator was constructed and tested on site. The results of experiment and simulation show that the thermal neutron flux at the end of theneutron collimator is greater than 10^6 n/cm^2/s, the maximum collimation ratio (L/D) is 58, the Cd-ratio(Mn) is 160 and the diameter of collimator end is 10 cm. This neutron collimator is considered to be applicable for neutron radiography.

  15. Neutron and photon fields in the BNCT room with closed beam shutters

    International Nuclear Information System (INIS)

    The epithermal neutron beam at the LVR-15 reactor was designed for the Boron Neutron Capture Therapy (BNCT) of cancers, but it has also been used for material testing. In the case where the beam is closed with two designed shutters, there is still an indispensable background in the irradiation room, which limits the movement of persons during patient positioning before exposure or during the preparation of the samples. Because the epithermal filter of the beam was designed in a former thermal column, as a multi-layer system, it was suspected that both fast neutrons and photons penetrated the filter shielding into the room. The purpose of this study was to determine the causes of potential faulty shielding and to estimate the doses to persons who perform the irradiation experiments and/or exposure of patients. The quality of the shielding was evaluated from two-dimensional measurements of both neutron and photon distribution on the surface of the beam shutter. During the measurement both the shutters of the epithermal beam were closed and the reactor was operated at the nominal power of 9 MW. This experimental arrangement is similar to the conditions that exist when either the irradiation experiments or the exposure of patients is performed in this room. The neutron space distribution was measured using a Bonner sphere of φ 76.2 mm diameter with an LiI(Tl) scintillation detector of φ 4 x 8 mm. A small Geiger-Muller tube was used for the measurement of photon distribution. The detectors were placed on a three-dimensional positioning equipment controlled by a computer, which enabled automatic measurement with 1 cm mesh step. Results of the measurement show that the background profile in the irradiation room has reasonable maximum only at the beam aperture. Published by Univ. of Press. All rights reserved. (authors)

  16. An optimized neutron-beam shaping assembly for accelerator-based BNCT

    International Nuclear Information System (INIS)

    Different materials and proton beam energies have been studied in order to search for an optimized neutron production target and beam shaping assembly for accelerator-based BNCT. The solution proposed in this work consists of successive stacks of Al, polytetrafluoroethylene, commercially known as Teflon[reg ], and LiF as moderator and neutron absorber, and Pb as reflector. This assembly is easy to build and its cost is relatively low. An exhaustive Monte Carlo simulation study has been performed evaluating the doses delivered to a Snyder model head phantom by a neutron production Li-metal target based on the 7Li(p,n)7Be reaction for proton bombarding energies of 1.92, 2.0, 2.3 and 2.5 MeV. Three moderator thicknesses have been studied and the figures of merit show the advantage of irradiating with near-resonance-energy protons (2.3 MeV) because of the relatively high neutron yield at this energy, which at the same time keeps the fast neutron healthy tissue dose limited and leads to the lowest treatment times. A moderator of 34 cm length has shown the best performance among the studied cases

  17. Feasibility study of using laser-generated neutron beam for BNCT

    International Nuclear Information System (INIS)

    The feasibility of using a laser-accelerated proton beam to produce a neutron source, via (p,n) reaction, for Boron Neutron Capture Therapy (BNCT) applications has been studied by MCNPX Monte Carlo code. After optimization of the target material and its thickness, a Beam Shaping Assembly (BSA) has been designed and optimized to provide appropriate neutron beam according to the recommended criteria by International Atomic Energy Agency. It was found that the considered laser-accelerated proton beam can provide epithermal neutron flux of ∼2×106 n/cm2 shot. To achieve an appropriate epithermal neutron flux for BNCT treatment, the laser must operate at repetition rates of 1 kHz, which is rather ambitious at this moment. But it can be used in some BNCT researches field such as biological research. - Highlights: • Feasibility of using laser-accelerated proton beam for BNCT has been investigated. • The considered beam can provide epithermal neutron flux of ~2×106 (n/cm2.shot). • For BNCT treatment, the laser must operate at repetition rates of 1 kHz

  18. Effective dose evaluation for BNCT treatment in the epithermal neutron beam at THOR

    International Nuclear Information System (INIS)

    This paper aims to evaluate the effective dose as well as equivalent doses of several organs of an adult hermaphrodite mathematical phantom according to the definition of ICRP Publication 60 for BNCT treatments of brain tumors in the epithermal neutron beam at THOR. The MCNP5 Monte Carlo code was used for the calculation of the average absorbed dose of each organ. The effective doses for a typical brain tumor treatment with a tumor treatment dose of 20 Gy-eq were evaluated to be 0.59 and 0.35 Sv for the LLAT and TOP irradiation geometries, respectively. In addition to the stochastic effect, it was found that it is also likely to produce deterministic effects, such as cataracts and depression of haematopoiesis.

  19. Application of an ultraminiature thermal neutron monitor for irradiation field study of accelerator-based neutron capture therapy

    International Nuclear Information System (INIS)

    Phantom experiments to evaluate thermal neutron flux distribution were performed using the Scintillator with Optical Fiber (SOF) detector, which was developed as a thermal neutron monitor during boron neutron capture therapy (BNCT) irradiation. Compared with the gold wire activation method and Monte Carlo N-particle (MCNP) calculations, it was confirmed that the SOF detector is capable of measuring thermal neutron flux as low as 105 n/cm2/s with sufficient accuracy. The SOF detector will be useful for phantom experiments with BNCT neutron fields from low-current accelerator-based neutron sources. (author)

  20. Computational dosimetry of a simulated combined standard X-Rays and BNCT treatment

    Energy Technology Data Exchange (ETDEWEB)

    Casal, M.R., E-mail: mcasal@cnea.gov.ar [Instituto de Oncologia ' Angel H. Roffo' , Universidad de Buenos Aires, Av. San Martin 5481, Bs.As. (Argentina)] [Comision Nacional de Energia Atomica, Av. General Paz 1499, San Martin, Buenos Aires (Argentina); Herrera, M.S., E-mail: mariettaherrera@gmail.com [Comision Nacional de Energia Atomica, Av. General Paz 1499, San Martin, Buenos Aires (Argentina)] [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) Av. Rivadavia 191, Buenos Aires (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad de General San Martin, 25 de Mayo and M. de Irigoyen, San Martin (Argentina); Gonzalez, S.J., E-mail: srgonzal@cnea.gov.ar [Comision Nacional de Energia Atomica, Av. General Paz 1499, San Martin, Buenos Aires (Argentina)] [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) Av. Rivadavia 191, Buenos Aires (Argentina)

    2011-12-15

    There has been increasing interest in combining Boron Neutron Capture Therapy (BNCT) with standard radiotherapy, either concomitantly or as a BNCT treatment of a recurrent tumor that was previously irradiated with a medical electron linear accelerator (LINAC). In this work we report the simulated dosimetry of treatments combining X-rays and BNCT

  1. FiR 1 Reactor in Service for Boron Neutron Capture Therapy (BNCT) and Isotope Production

    International Nuclear Information System (INIS)

    The FiR 1 reactor, a 250 kW Triga reactor, has been in operation since 1962. The main purpose to run the reactor is now the Boron Neutron Capture Therapy (BNCT). Although BNCT dominates the current utilization of the reactor, it also has an important national role in providing local enterprises and research institutions in the fields of industrial measurements, pharmaceuticals, electronics, etc. with isotope produc- tion and activation analysis services. The whole reactor building has been renovated, creating a dedicated clinical BNCT facility at the reactor. Close to 30 patients have been treated since May 1999, when the licence for patient treatment was granted to the responsible BNCT treatment organization. The treatment organization has a close connection to the Helsinki University Central Hospital. (author)

  2. Feasibility of sealed D–T neutron generator as neutron source for liver BNCT and its beam shaping assembly

    International Nuclear Information System (INIS)

    This paper involves the feasibility of boron neutron capture therapy (BNCT) for liver tumor with four sealed neutron generators as neutron source. Two generators are placed on each side of the liver. The high energy of these emitted neutrons should be reduced by designing a beam shaping assembly (BSA) to make them useable for BNCT. However, the neutron flux decreases as neutrons pass through different materials of BSA. Therefore, it is essential to find ways to increase the neutron flux. In this paper, the feasibility of using low enrichment uranium as a neutron multiplier is investigated to increase the number of neutrons emitted from D-T neutron generators. The neutron spectrum related to our system has a proper epithermal flux, and the fast and thermal neutron fluxes comply with the IAEA recommended values. - Highlights: • The feasibility of sealed neutron generator as neutron source for liver BNCT. • Using natural uranium and low enrichment uranium as neutron multiplier for D–T generator is examined. • A beam shaping assembly is designed to optimize the output neutron beam. • The output of the assembly can fulfill the beam port recommended quality parameters by IAEA

  3. Boron neutron capture therapy (BNCT) inhibits tumor development from precancerous tissue: An experimental study that supports a potential new application of BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Monti Hughes, A.; Heber, E.M. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina); Pozzi, E. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina); Department of Research and Production Reactors, Ezeiza Atomic Center, CNEA, Buenos Aires (Argentina); Nigg, D.W. [Idaho National Laboratory, Idaho Falls, Idaho (United States); Calzetta, O.; Blaumann, H.; Longhino, J. [Department of Nuclear Engineering, Bariloche Atomic Center, CNEA, Rio Negro (Argentina); Nievas, S.I. [Department of Chemistry, CNEA, Buenos Aires (Argentina); Aromando, R.F. [Department of Oral Pathology, Faculty of Dentistry, University of Buenos Aires, Buenos Aires (Argentina); Itoiz, M.E. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina); Department of Oral Pathology, Faculty of Dentistry, University of Buenos Aires, Buenos Aires (Argentina); Trivillin, V.A. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina); Schwint, A.E. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina)], E-mail: schwint@cnea.gov.ar

    2009-07-15

    We previously demonstrated the efficacy of boron neutron capture therapy (BNCT) mediated by boronophenylalanine (BPA), GB-10 (Na{sub 2}{sup 10}B{sub 10}H{sub 10}) and (GB-10+BPA) to control tumors, with no normal tissue radiotoxicity, in the hamster cheek pouch oral cancer model. Herein we developed a novel experimental model of field-cancerization and precancerous lesions (globally termed herein precancerous tissue) in the hamster cheek pouch to explore the long-term potential inhibitory effect of the same BNCT protocols on the development of second primary tumors from precancerous tissue. Clinically, second primary tumor recurrences occur in field-cancerized tissue, causing therapeutic failure. We performed boron biodistribution studies followed by in vivo BNCT studies, with 8 months follow-up. All 3 BNCT protocols induced a statistically significant reduction in tumor development from precancerous tissue, reaching a maximum inhibition of 77-100%. The inhibitory effect of BPA-BNCT and (GB-10+BPA)-BNCT persisted at 51% at the end of follow-up (8 months), whereas for GB-10-BNCT it faded after 2 months. Likewise, beam-only elicited a significant but transient reduction in tumor development. No normal tissue radiotoxicity was observed. At 8 months post-treatment with BPA-BNCT or (GB-10+BPA)-BNCT, the precancerous pouches that did not develop tumors had regained the macroscopic and histological appearance of normal (non-cancerized) pouches. A potential new clinical application of BNCT would lie in its capacity to inhibit local regional recurrences.

  4. Tumor development in field-cancerized tissue is inhibited by a double application of Boron neutron capture therapy (BNCT) without exceeding radio-tolerance

    International Nuclear Information System (INIS)

    Introduction: BNCT is based on the capture reaction between boron, selectively targeted to tumor tissue, and thermal neutrons which gives rise to lethal, short-range high linear energy transfer particles that selectively damage tumor tissue, sparing normal tissue. We previously evidenced a remarkable therapeutic success of a 'single' application of boron neutron capture therapy (BNCT) mediated by boronophenylalanine (BPA), GB-1(Na210B10H10) or (GB-10+BPA) to treat hamster cheek pouch tumors with no normal tissue radiotoxicity. Based on these results, we developed a model of precancerous tissue in the hamster cheek pouch for long-term studies. Employing this model we evaluated the long-term potential inhibitory effect on the development of second primary tumors from precancerous tissue and eventual radiotoxicity of a single application of BNCT mediated by BPA, GB-10 or (GB-10+BPA), in the RA-6. The clinical rationale of this study was to search for a BNCT protocol that is therapeutic for tumor, not radio-toxic for the normal tissue that lies in the neutron beam path, and exerts the desired inhibitory effect on the development of second primary tumors, without exceeding the radio-tolerance of precancerous tissue, the dose limiting tissue in this case. Second primary tumors that arise in precancerous tissue (also called locoregional recurrences) are a frequent cause of therapeutic failure in head and neck tumors. Aim: Evaluate the radiotoxicity and inhibitory effect of a 'double' application of the same BNCT protocols that were proved therapeutically successful for tumor and precancerous tissue, with a long term follow up (8 months). A 'double' application of BNCT is a potentially useful strategy for the treatment of tumors, in particular the larger ones, but the cost in terms of side-effects in dose-limiting tissues might preclude its application and requires cautious evaluation. Materials and methods: We performed a double application of 1) BPA-BNCT; 2) (GB- 10+BPA)-BNCT

  5. BNCT activities at Slovenian TRIGA research reactor

    International Nuclear Information System (INIS)

    It has been reported that satisfactory thermal/epithermal neutron beams for Boron Neutron Capture Therapy (BNCT) could be designed at TRIGA research reactors These reactors are generally perceived as being safe to install and operate in populated areas. This contribution presents the most recent BNCT research activities on the 'Jozef Stefan' Institute, where epithermal neutron beam for 'in-vitro' irradiation has been developed and experimentally verified. Furthermore, The Monte Carlo feasibility study of development of the epithermal neutron beam for BNCT clinical trials of human patients in thermalising column (TC) of TRIGA reactor has been carried out. The simulation results prove, that a BNCT irradiation facility with performances, comparable to existing beam throughout the world, could be installed in TC of the TRIGA reactor. (author)

  6. BNCT enhanced fast neutron therapy: in vitro studies for preparing a clinical trial at the Essen cyclotron

    International Nuclear Information System (INIS)

    At the University Hospital Essen a cyclotron producing d(14)+Be fast neutrons is used routinely for patient treatment. Fast neutrons have demonstrated their potential to sterilize glioblastoma but could not show a clinical benefit because of lethal damages to healthy brain. At depth, fast neutrons are thermalized allowing neutron capture reactions, which can be used to enhance the applied dose. A selective increase of the dose to the tumor cells by BNCT may offer a chance to an effective treatment. In order to prepare a clinical trial in vitro experiments were performed. MeWo cells were irradiated in a tissue equivalent phantom at a depth of 6.5 cm. 91% 10B enriched BSH was used to generate BNC effects. For a total dose of 1 Gy the thermal fluence rate was 3.4x1010 cm-2. An amount of 960 ppm 10B present in the cell medium during irradiation led to a reduction of the cell survival from 3.6% (neutron alone) to 0.2%. If the irradiation was performed after incubation of the cells in BSH, but in a medium without BSH the survival was 1.6%. The in vitro set up demonstrates the capacity of BSH to considerably increase the biological effects of the neutron irradiation and add arguments for the opening of a clinical trial. (author)

  7. Characteristics and application of spherical-type activation detectors in neutron spectrum measurements at a boron neutron capture therapy (BNCT) facility

    Science.gov (United States)

    Lin, Heng-Xiao; Chen, Wei-Lin; Liu, Yuan-Hao; Sheu, Rong-Jiun

    2016-03-01

    A set of spherical-type activation detectors was developed aiming to provide better determination of the neutron spectrum at the Tsing Hua Open-pool Reactor (THOR) BNCT facility. An activation foil embedded in a specially designed spherical holder exhibits three advantages: (1) minimizing the effect of neutron angular dependence, (2) creating response functions with broadened coverage of neutron energies by introducing additional moderators or absorbers to the central activation foil, and (3) reducing irradiation time because of improved detection efficiencies to epithermal neutron beam. This paper presents the design concept and the calculated response functions of new detectors. Theoretical and experimental demonstrations of the performance of the detectors are provided through comparisons of the unfolded neutron spectra determined using this method and conventional multiple-foil activation techniques.

  8. Neutron and gamma dose rates determined in a cell phantom at the Finnish BNCT facility

    International Nuclear Information System (INIS)

    Radiation dosimetry studies have played an essential role in the Finnish BNCT (Boron Neutron Capture Therapy) project. Various phantom studies have been carried out in the FiR I epithermal neutron beam to characterise the gamma and the neutron dose distributions involved in the patient treatment circumstances and to evaluate the beam model used for dose planning. During the summer 1999 cell-line phantom irradiations were done. Dose calculations and measurements were required to determine the dose delivered to the cells at the different locations in the phantom. A cylindrical water-filled polyethylene phantom was used in contact with the 14 cm diameter circular beam aperture. The phantom was modelled by deterministic DORT code. Activation detectors (MT-AI wires), twin (Mg and TE) ionisations chambers (IC) and TL detectors were used to establish the measured dose and 55Mn(n,γ) reaction rates compared to the calculated values. The measured (IC) and calculated gamma and neutron dose rates at three depths in the phantom will be presented. The measured gamma dose rates were about 10 % lower, and the neutron dose rates about 35% lower than the calculations. The difference between the measured 55Mn reaction rates and the calculations was insignificant (= 1%). During the measurements the reactor was operated at the nominal power of 250 kW. The measured (IC) gamma dose rates were in fair agreement with the calculated values but the neutron dose rates displayed considerable discrepancy. However, the activation results, having the best accuracy, were very consistent with the calculated 55Mn reaction rates and therefore the dose determination could be based on the simulated results (author)

  9. The epithermal neutron beam for BNCT under construction at TAPIRO: Physics

    International Nuclear Information System (INIS)

    A column to provide an epithermal neutron beam suitable for experimental and clinical BNCT is nearing completion at the TAPIRO reactor (ENEA Casaccia, Rome). TAPIRO is a compact, low power (5 kW), helium-cooled, fast reactor. It has a hard neutron spectrum relative even to other fast reactors. In this paper some of the basic physics aspects of designing an epithermal neutron beam are considered, with reference to the TAPIRO beam

  10. Boron Neutron Capture Therapy (BNCT) Breaks New Ground for Cancer Radiotherapy

    International Nuclear Information System (INIS)

    10B nucleus captures a slow speed neutron (thermal neutron), and imediately the nucleus slits into 4He nucleus and 7Li nucleus, These have very short track rangs that don't exceed general cell diameter. So, if 10B-compound accumulates in cancer cells by considerable selectivity, the cancer is destroyed selectively. BNCT was applied to malignant brain tumor (GBM) in USA for 10 years (1951-1961). In Japan the clinical study was done for GBM in 1968, and thereafter, malignant melanoma of the skin was also treated by BNCT using Kyoto University Research Reactor (KUR). In 2001, the first application to the recurrent H&N cancer was performed at KURRI and scored a great sucess. The research team of KURRI have performed a lot of BNCT using KUR neutron beam in collaboration with many co-investrigatiors outside KURRI. The current number of BNCT exceeded 660 (over 50% of total BNCT in the world). It includes several world's first trials represented by case of recurrent head and neck cancers, malignant pleural mesotheliomas, local recurrence of digestive organ cancers and breast cancers. The utility of FBPA PET for sucessful BNCT has been also asscssed. Based on these achievement, we earnestly promoted the project to develop an accelerator BNCT system from 2007. The neutron fluence rate must be high sufficiently and stable at least for 1 hour. An equipment has to casyto operate and small enough in order to install in a hospital. The operation cost of the equipment also have to be inexpensive for the future spread. We chose a cyclotron, 30 MeV proton, over 1 Ma of electric current and a beryllium target. After pre-clinical tests on neutron beam characteristics, phase I clinical test was started in 2012 to examine the safety and acceptability of neutron system, boron compound BPA and their combination. The first target cancer is a recurrent malignat glioma, and the second is an inoperable locally advanced or recurrent head and neck cancer. For malignant glioma, it

  11. The time-of-flight epithermal neutron spectrum measurement from accelerator based BNCT facility

    International Nuclear Information System (INIS)

    Results of epithermal neutrons spectrum measurement by time-of-flight method for different beam shaping assembly designed for BNCT purposes are presented. Discuss method to realize time-of-flight measurement at accelerator. Results looks are important for beam shaping assembly optimization and accurate and reliable treatment planning. (author)

  12. An optimum source neutron spectrum and holder shape for extra-corporal treatment of liver cancer by BNCT

    International Nuclear Information System (INIS)

    In extra-corporal treatment of liver cancer by BNCT, it is desired to have an as homogeneous as possible thermal neutron field throughout the organ. Previous work has shown that when using an epithermal neutron beam, the shape of the holder in which the liver is placed is the critical factor. This study develops the notion further as to what is the optimum neutron spectrum to perform such treatments. In the design calculations, when using Monte Carlo techniques, it is shown that when the expected contributions of the source neutrons in every part of the liver is calculated, a linear optimization scheme such as the Simplex method results in a mix of thermal and epithermal source neutrons to get the highest homogeneity for the thermal neutron field. This optimisation method is demonstrated in 3 holder shapes: cuboid, cylindrical and spherical with each 3 volumes of 2, 4 and 6 litres. A 10 cm thick cuboid model, irradiated from both sides gives the highest homogeneity. The spherical (rotating) holder has the lowest homogeneity but the highest contribution of every source neutron to the thermal neutrons in the liver. This can be advantageous when using a relatively small sized neutron beam with a low strength. (author)

  13. Neutron-photon mixed field dosimetry by TLD-700 glow curve analysis and its implementation in dose monitoring for Boron Neutron Capture Therapy (BNCT) treatments

    Energy Technology Data Exchange (ETDEWEB)

    Boggio, E. F.; Longhino, J. M. [Centro Atomico Bariloche, Departamento de Fisica de Reactores y Radiaciones / CNEA, Av. E. Bustillo Km 9.5, R8402AGP San Carlos de Bariloche (Argentina); Andres, P. A., E-mail: efboggio@cab.cnea.gov.ar [Centro Atomico Bariloche, Division Proteccion Radiologica / CNEA, Av. E. Bustillo Km 9.5, R8402AGP San Carlos de Bariloche (Argentina)

    2015-10-15

    BNCT is a cancerous cells selective, non-conventional radiotherapy modality to treat malignant tumors such as glioblastoma, melanoma and recurrent head and neck cancer. It consists of a two-step procedure: first, the patient is injected with a tumor localizing drug containing a non-radioactive isotope (Boron-10) with high slow neutron capture cross-section. In a second step, the patient is irradiated with neutrons, which are absorbed by the Boron-10 agent with the subsequently nuclear reaction B- 10(n,a)Li-7, thereby resulting in dose at cellular level due to the high-Let particles. The neutron fields suitable for BNCT are characterized by high neutron fluxes and low gamma dose. Determination of each component is not an easy task, especially when the volume of measurement is quite small or inaccessible for a miniature ionization chamber, for example. A method of measuring the photon and slow neutron dose(mainly by N-14 and B-10) from the glow curve (GC) analysis of a single {sup 7}LiF thermoluminescence detector is evaluated. This method was suggested by the group headed by Dr. Grazia Gambarini. The dosemeters used were TLD-600 ({sup 6}LiF:Mg,Ti with 95.6% {sup 6}Li) and TLD-700 ({sup 7}LiF:Mg,Ti with 99.9% {sup 7}LiF) from Harshaw. Photon dose measurement using the GC analysis method with TLD-700 in mixed fields requires the relation of the two main peaks of a TLD-600 GC shape obtained from an exposition to the same neutron field, and a photon calibrated GC with TLD-700. The requirements for slow neutron dose measurements are similar. In order to properly apply the GC analysis method at the Ra-6 Research Reactor BNCT facility, measurements were carried out in a standard water phantom, fully characterized on the BNCT beam by conventional techniques (activation detectors and paired ionization chambers technique). Next, the method was implemented in whole body dose monitoring of a patient undergoing a BNCT treatment, using a Bo MAb (Bottle Manikin Absorption) phantom

  14. Neutron-photon mixed field dosimetry by TLD-700 glow curve analysis and its implementation in dose monitoring for Boron Neutron Capture Therapy (BNCT) treatments

    International Nuclear Information System (INIS)

    BNCT is a cancerous cells selective, non-conventional radiotherapy modality to treat malignant tumors such as glioblastoma, melanoma and recurrent head and neck cancer. It consists of a two-step procedure: first, the patient is injected with a tumor localizing drug containing a non-radioactive isotope (Boron-10) with high slow neutron capture cross-section. In a second step, the patient is irradiated with neutrons, which are absorbed by the Boron-10 agent with the subsequently nuclear reaction B- 10(n,a)Li-7, thereby resulting in dose at cellular level due to the high-Let particles. The neutron fields suitable for BNCT are characterized by high neutron fluxes and low gamma dose. Determination of each component is not an easy task, especially when the volume of measurement is quite small or inaccessible for a miniature ionization chamber, for example. A method of measuring the photon and slow neutron dose(mainly by N-14 and B-10) from the glow curve (GC) analysis of a single 7LiF thermoluminescence detector is evaluated. This method was suggested by the group headed by Dr. Grazia Gambarini. The dosemeters used were TLD-600 (6LiF:Mg,Ti with 95.6% 6Li) and TLD-700 (7LiF:Mg,Ti with 99.9% 7LiF) from Harshaw. Photon dose measurement using the GC analysis method with TLD-700 in mixed fields requires the relation of the two main peaks of a TLD-600 GC shape obtained from an exposition to the same neutron field, and a photon calibrated GC with TLD-700. The requirements for slow neutron dose measurements are similar. In order to properly apply the GC analysis method at the Ra-6 Research Reactor BNCT facility, measurements were carried out in a standard water phantom, fully characterized on the BNCT beam by conventional techniques (activation detectors and paired ionization chambers technique). Next, the method was implemented in whole body dose monitoring of a patient undergoing a BNCT treatment, using a Bo MAb (Bottle Manikin Absorption) phantom, with representative

  15. The Argonne ACWL, a potential accelerator-based neutron source for BNCT

    International Nuclear Information System (INIS)

    THE CWDD (Continuous Wave Deuterium Demonstrator) accelerator was designed to accelerate 80 mA cw of D- to 7.5 MeV. Most of the hardware for the first 2 MeV was installed at Argonne and major subsystems had been commissioned when program funding from the Ballistic Missile Defense Organization ended in October 1993. Renamed the Argonne Continuous Wave Linac (ACWL), we are proposing to complete it to accelerate either deuterons to 2 MeV or protons to 3-3.5 MeV. Equipped with a beryllium or other light-element target, it would make a potent source of neutrons (on the order of 1013 n/s) for BNCT and/or neutron radiography. Project status and proposals for turning ACWL into a neutron source are reviewed, including the results of a computational study that was carried out to design a target/moderator to produce an epithermal neutron beam for BNCT. (orig.)

  16. First tomographic image of neutron capture rate in a BNCT facility

    International Nuclear Information System (INIS)

    This work discusses the development of online dosimetry of the boron dose via Single Photon Emission Computed Tomography (SPECT) during a BNCT treatment irradiation. Such a system will allow the online computation of boron dose maps without the large current uncertainties in the assessment of the boron concentration in different tissues. The first tomographic boron dose image with a SPECT prototype is shown.

  17. The Boron Neutron Capture Therapy (BNCT) Project at the TRIGA Reactor in Mainz, Germany

    Energy Technology Data Exchange (ETDEWEB)

    Hampel, G.; Grunewald, C.; Schutz, C.; Schmitz, T.; Kratz, J.V. [Nuclear Chemistry, University of Mainz, D-55099 Mainz (Germany); Brochhausen, C.; Kirkpatrick, J. [Department of Pathology, University of Mainz, D-55099 Mainz (Germany); Bortulussi, S.; Altieri, S. [Department of Nuclear and Theoretical Physics University of Pavia, Pavia (Italy); National Institute of Nuclear Physics (INFN) Pavia Section, Pavia (Italy); Kudejova, P. [Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), Technische Universitaet Muenchen, D-85748 Garching (Germany); Appelman, K.; Moss, R. [Joint Research Centre (JRC) of the European Commission, NL-1755 ZG Petten (Netherlands); Bassler, N. [University of Aarhus, Norde Ringade, DK-8000, Aarhus C (Denmark); Blaickner, M.; Ziegner, M. [Molecular Medicine, Health and Environment Department, AIT Austrian Institute of Technology GmbH (Austria); Sharpe, P.; Palmans, H. [National Physical Laboratory, Teddington TW11 0LW, Middlesex (United Kingdom); Otto, G. [Department of Hepatobiliary, Pancreatic and Transplantation Surgery, University of Mainz, D-55099 Mainz (Germany)

    2011-07-01

    The thermal column of the TRIGA reactor in Mainz is being used very effectively for medical and biological applications. The BNCT (boron neutron capture therapy) project at the University of Mainz is focussed on the treatment of liver tumours, similar to the work performed in Pavia (Italy) a few years ago, where patients with liver metastases were treated by combining BNCT with auto-transplantation of the organ. Here, in Mainz, a preclinical trial has been started on patients suffering from liver metastases of colorectal carcinoma. In vitro experiments and the first animal tests have also been initiated to investigate radiobiological effects of radiation generated during BNCT. For both experiments and the treatment, a reliable dosimetry system is necessary. From work elsewhere, the use of alanine detectors appears to be an appropriate dosimetry technique. (author)

  18. Application of an ultraminiature thermal neutron monitor for irradiation field study of accelerator-based neutron capture therapy

    OpenAIRE

    Ishikawa, Masayori; Tanaka, Kenichi; Endo, Satrou; Hoshi, Masaharu

    2015-01-01

    Phantom experiments to evaluate thermal neutron flux distribution were performed using the Scintillator with Optical Fiber (SOF) detector, which was developed as a thermal neutron monitor during boron neutron capture therapy (BNCT) irradiation. Compared with the gold wire activation method and Monte Carlo N-particle (MCNP) calculations, it was confirmed that the SOF detector is capable of measuring thermal neutron flux as low as 105 n/cm2/s with sufficient accuracy. The SOF detector will be u...

  19. Application of an ultraminiature thermal neutron monitor for irradiation field study of accelerator-based neutron capture therapy

    OpenAIRE

    Ishikawa, Masayori; Tanaka, Kenichi; Endo, Satrou; Hoshi, Masaharu

    2015-01-01

    Phantom experiments to evaluate thermal neutron flux distribution were performed using the Scintillator with Optical Fiber (SOF) detector, which was developed as a thermal neutron monitor during boron neutron capture therapy (BNCT) irradiation. Compared with the gold wire activation method and Monte Carlo N-particle (MCNP) calculations, it was confirmed that the SOF detector is capable of measuring thermal neutron flux as low as 105 n/cm2/s with sufficient accuracy. The SOF detector ...

  20. High neutronic efficiency, low current targets for accelerator-based BNCT applications

    International Nuclear Information System (INIS)

    The neutronic efficiency of target/filters for accelerator-based BNCT applications is measured by the proton current required to achieve a desirable neutron current at the treatment port (109 n/cm2/s). In this paper the authors describe two possible targeyt/filter concepts wihch minimize the required current. Both concepts are based on the Li-7 (p,n)Be-7 reaction. Targets that operate near the threshold energy generate neutrons that are close tothe desired energy for BNCT treatment. Thus, the filter can be extremely thin (∼ 5 cm iron). However, this approach has an extremely low neutron yield (n/p ∼ 1.0(-6)), thus requiring a high proton current. The proposed solutino is to design a target consisting of multiple extremely thin targets (proton energy loss per target ∼ 10 keV), and re-accelerate the protons between each target. Targets operating at ihgher proton energies (∼ 2.5 MeV) have a much higher yield (n/p ∼ 1.0(-4)). However, at these energies the maximum neutron energy is approximately 800 keV, and thus a neutron filter is required to degrade the average neutron energy to the range of interest for BNCT (10--20 keV). A neutron filter consisting of fluorine compounds and iron has been investigated for this case. Typically a proton current of approximately 5 mA is required to generate the desired neutron current at the treatment port. The efficiency of these filter designs can be further increased by incorporating neutron reflectors that are co-axial with the neutron source. These reflectors are made of materials which have high scattering cross sections in the range 0.1--1.0 MeV

  1. Fast-neutron dose evaluation in BNCT with Fricke gel layer detectors

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G., E-mail: grazia.gambarini@mi.infn.i [Universita degli Studi di Milano, Department of Physics, Via Celoria 16, 20133 Milano (Italy); INFN Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Bartesaghi, G. [Universita degli Studi di Milano, Department of Physics, Via Celoria 16, 20133 Milano (Italy); INFN Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Burian, J. [Department of Reactor Physics, Nuclear Research Institute Rez, Husinec - Rez 130, 250 68 Rez (Czech Republic); Carrara, M., E-mail: mauro.carrara@istitutotumori.mi.i [Medical Physics Unit, Fondazione IRCCS ' Istituto Nazionale Tumori' , via Venezian 1, 20133 Milano (Italy); Marek, M. [Department of Reactor Physics, Nuclear Research Institute Rez, Husinec - Rez 130, 250 68 Rez (Czech Republic); Negri, A. [Universita degli Studi di Milano, Department of Physics, Via Celoria 16, 20133 Milano (Italy); INFN Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Pirola, L. [Universita degli Studi di Milano, Department of Physics, Via Celoria 16, 20133 Milano (Italy); Viererbl, L. [Department of Reactor Physics, Nuclear Research Institute Rez, Husinec - Rez 130, 250 68 Rez (Czech Republic)

    2010-12-15

    Boron neutron capture therapy (BNCT) is a cancer radiotherapy that uses epithermal and thermal neutron beams. The determination of the absorbed dose in healthy tissue, separating the various dose contributions having different radiobiological effectiveness (RBE) is of great importance for therapy planning. However, a standard code of practice has not yet been established because suitable methods for dosimetry in BNCT are still in progress. A study about the characterization of the epithermal column of the LVR-15 research reactor in Rez (CZ) has been performed, in particular concerning the fast-neutron dose. This dose is not negligible and its determination is important owing to its high RBE. Fast-neutron and photon dose distributions in a water phantom have been measured by means of Fricke gel layer dosimeters. Even if gel layer dosimetry is not yet standardized, it is presently the only method for obtaining images of each dose contribution in BNCT neutron fields. The results were compared with values measured with thermoluminescence detectors, twin ionization chambers data taken from literature and Monte Carlo simulations.

  2. BNCT facility development in HANARO

    International Nuclear Information System (INIS)

    An irradiation facility for boron neutron capture therapy (BNCT) was developed using one of the typical tangential beam tubes in HANARO. Thermal neutron was chosen because of the impossibility of sufficient epithermal neutrons for BNCT at the exit of the beam tube. The facility is designed not only for BNCT study but also for dynamic neutron radiography (DNR) and other experiments requiring pure thermal neutrons. Silicon and bismuth single crystals cooled by liquid nitrogen are selected to filter out fast neutrons and γ-rays and to penetrate the thermal neutrons as much as possible. A water shutter is installed in front of the radiation filter to keep the radiation level low in the irradiation room while it is filled with water. A prompt gamma neutron activation analysis (PGNAA) system was also developed to measure the boron concentration quickly from patient's blood samples. A spare neutron beam from a dedicated beam instrument was diffracted upward using pyrolytic graphite to obtain almost pure thermal neutrons at the target position. (author)

  3. FiR 1 reactor in service for boron neutron capture therapy (BNCT) and isotope production

    International Nuclear Information System (INIS)

    The FiR 1 reactor, a 250 kW Triga reactor, has been in operation since 1962. The main purpose for the existence of the reactor is now the Boron Neutron Capture Therapy (BNCT), but FiR 1 has also an important national role in providing local enterprises and research institutions in the fields of industrial measurements, pharmaceuticals, electronics etc. with isotope production and activation analysis services. In the 1990's a BNCT treatment facility was built at the FiR 1 reactor located at Technical Research Centre of Finland. A special new neutron moderator material FluentalTM (Al+AlF3+Li) developed at VTT ensures the superior quality of the neutron beam. Also the treatment environment is of world top quality after a major renovation of the whole reactor building in 1997. Recently the lithiated polyethylene neutron shielding of the beam aperture was modified to ease the positioning of the patient close to the beam aperture. Increasing the reactor power to 500 kW would allow positioning of the patient further away from the beam aperture. Possibilities to accomplish a safety analysis for this is currently under considerations. Over thirty patients have been treated at FiR 1 since May 1999, when the license for patient treatment was granted to the responsible BNCT treatment organization, Boneca Corporation. Currently three clinical trial protocols for tumours in the brain as well as in the head and neck region are recruiting patients. (author)

  4. Performance evaluation of the source description of the THOR BNCT epithermal neutron beam

    International Nuclear Information System (INIS)

    This paper aims to evaluate the performance of the source description of the THOR BNCT beam via different measurement techniques in different phantoms. The measurement included (1) the absolute reaction rate measurement of a set of triple activation foils, (2) the neutron and gamma-ray dose rates measured using the paired ionization chamber method, and (3) the relative reaction rate distributions obtained using the indirect neutron radiography. Three source descriptions, THOR-Y09, surface source file RSSA, and THOR-50C, were tested. The comparison results concluded that THOR-Y09 is a well-tested source description not only for neutron components, but also for gamma-ray component.

  5. A comparison of neutron beams for BNCT based on in-phantom neutron field assessment parameters

    International Nuclear Information System (INIS)

    In this paper our in-phantom neutron field assessment parameters, T and DTumor, were used to evaluate several neutron sources for use in BNCT. Specifically, neutron fields from The Ohio State University (OSU) Accelerator-Based Neutron Source (ABNS) design, two alternative ABNS designs from the literature (the Al/AlF3-Al2O3 ABNS and the 7LiF-Al2O3 ABNS), a fission-convertor plate concept based on the 500-kW OSU Research Reactor (OSURR), and the Brookhaven Medical Research Reactor (BMRR) facility were evaluated. In order to facilitate a comparison of the various neutron fields, values of T and DTumor were calculated in a 14 cmx14 cmx14 cm lucite cube phantom located in the treatment port of each neutron source. All of the other relevant factors, such as phantom materials, kerma factors, and treatment parameters, were kept the same. The treatment times for the OSURR, the 7LiF-Al2O3 ABNS operating at a beam current of 10 mA, and the BMRR were calculated to be comparable and acceptable, with a treatment time per fraction of approximately 25 min for a four fraction treatment scheme. The treatment time per fraction for the OSU ABNS and the Al/AlF3-Al2O3 ABNS can be reduced to below 30 min per fraction for four fractions, if the proton beam current is made greater than approximately 20 mA. DTumor was calculated along the beam centerline for tumor depths in the phantom ranging from 0 to 14 cm. For tumor depths ranging from 0 to approximately 1.5 cm, the value of DTumor for the OSURR is largest, while for tumor depths ranging from 1.5 to approximately 14 cm, the value of DTumor for the OSU-ABNS is the largest

  6. P13.09ADVANCES IN CLINICAL APPLICATION OF BORON NEUTRON CAPTURE THERAPY (BNCT) IN GLIOBLASTOMA

    OpenAIRE

    Detta, A.; Cruickshank, G.C.; Green, S.; Lockyer, N.P.; Ngoga, D.; Ghani, Z.; Phoenix, B

    2014-01-01

    BNCT is a biologically targeted form of enhanced cellular radiotherapy where preferential accumulation of boron in the cancerous as opposed to adjacent normal cells is able to interact with incident neutrons to cause irreversible alpha particle DNA damage. The key to the implementation of this potentially powerful and selective therapy is the delivery of at least 30ppm 10B within the tumour tissue while minimising superfluous 10B in healthy tissue. It is thus an elegant technique for treating...

  7. A colorimetric determination of boron in biological sample for boron neutron capture therapy (BNCT)

    International Nuclear Information System (INIS)

    The boron neutron capture therapy (BNCT) has shown better prognosis in the treatment of glyemas and gluoblastomas grade III and IV than other therapies. During the treatment the levels of Na210B12H11SH must be known in several compartiments of the organism and with this purpose the method of colorimetric determination of boron using curcumine was established. This method is simple, reprodutible and adequate sensitivity for this control. (author)

  8. Dosimetry of neutron irradiations

    International Nuclear Information System (INIS)

    Biological dosimetry of neutron irradiation appears to be of great difficulty due to the multiparametric aspect of the relative biological effectiveness and the heterogeneity of the neutron dose distribution. Dosimetry by sodium 24 activation which can be performed by means of portable radiameters appears to be very useful for early triage within the 3 h following neutron irradiation, whereas hematological dosimetry by slope and level analysis of the lymphocyte drop cannot be used in this case. Chromosomic aberration analysis allows to evaluate the neutron dose heterogeneity by the frequency measurement of acentric fragments not originating from the formation of dicentrics or rings. Finally, recent experimental data on large primate models (baboons) have shown that some plasma hemostasia factors appear to be reliable biological indicators and noticeable markers of the prognosis of neutron irradiation

  9. Determination of gamma dose and thermal neutron fluence in BNCT beams from the TLD-700 glow curve shape

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G., E-mail: grazia.gambarini@mi.infn.i [Universita degli Studi di Milano, Dipartimento di Fisica, via Celoria 16, 20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Bartesaghi, G. [Universita degli Studi di Milano, Dipartimento di Fisica, via Celoria 16, 20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Agosteo, S.; Vanossi, E. [Politecnico di Milano, Dipartimento di Energia, via Ponzio 34/3, 20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Carrara, M.; Borroni, M. [Fondazione IRCCS, Istituto Nazionale dei Tumori, Medical Physics Unit, via Venezian 1, 20133 Milano (Italy)

    2010-03-15

    The measurement of both gamma dose and thermal neutron fluence in a BNCT gamma-neutron mixed-field can be achieved by means of a single thermoluminescence dosimeter (TLD-700), exploiting the shape of the glow-curve (GC). The method is based on simple algorithms containing parameters obtained from the TLD-700 GC and requires the gamma calibration GC (for gamma dose measurement) or the thermal neutron calibration GC (for neutron fluence measurement) and moreover the GC of a TLD-600 exposed to a BNCT field, uncalibrated. Some results are reported, showing the potentiality of the method.

  10. Histopathological changes of testes and eyes by neutron irradiation with boron compounds in mice

    OpenAIRE

    Kim, Yeon-Joo; Yoon, Won-Ki; Ryu, Si-Yun; Chun, Ki-Jung; Son, Hwa-Young; Cho, Sung-Whan

    2006-01-01

    This study was performed to investigate the biological effects of boron neutron capture therapy (BNCT) on the testes and eyes in mice using HANARO Nuclear Reactor, Korea Atomic Energy Research Institute. BNCT relies on the high capacity of 10B in capturing thermal neutrons. Sodium borocaptate (BSH, 75 ppm, iv) and boronophenylalanine (BPA, 750 ppm, ip) have been used as the boron delivery agents. Mice were irradiated with neutron (flux: 1.036739E +09, Fluence 9.600200E+12) by lying flat pose ...

  11. Design and Construct of In-Hospital Neutron Irradiator

    International Nuclear Information System (INIS)

    The In-hospital neutron irradiator (IHNI) is designed based on the design of the Miniature Neutron Source Reactor (MNSR) for boron neutron capture therapy (BNCT), NAA, physics experiments, training and teaching. The reactor of the IHNI with thermal power 30 kW is an undermoderated reactor of pool-tank type, UO2 with enrichment of 12.5% as fuel, light water as coolant and moderator, and metal beryllium as reflector. The fission heat produced by the reactor is removed by the natural circulation. On the both sides of the reactor core, there are two neutron beams, one is a thermal neutron beam, and the other, opposite to the thermal beam, is an epithermal neutron beam. An experimental thermal neutron beam is specially designed for the prompt gamma neutron activation analysis (PGNAA). In this paper, the design and experiment results of IHNI will be introduced. (author)

  12. Design, construction and application of a neutron shield for the treatment of diffuse lung metastases in rats using BNCT

    International Nuclear Information System (INIS)

    A model of multiple lung metastases in BDIX rats is under study at CNEA (Argentina) to evaluate the feasibility of BNCT for multiple, non-surgically resectable lung metastases. A practical shielding device that comfortably houses a rat, allowing delivery of a therapeutic, uniform dose in lungs while protecting the body from the neutron beam is presented. Based on the final design obtained by numerical simulations, the shield was constructed, experimentally characterized and recently used in the first in vivo experiment at RA-3. - Highlights: • A practical shielding device that comfortably houses a rat is presented. • The shield allows a uniform and useful dose in the rat thoracic area. • A novel computational dosimetry in animals based on Multicell is presented. • Experimental characterization evidences the good performance of the shield. • An irradiation based on a diffuse lung metastases model in rats was performed

  13. Neutron irradiation of seeds

    International Nuclear Information System (INIS)

    Neutrons are a valuable type of ionizing radiation for seed irradiation and radiobiological studies and for inducing mutations in crop plants. In experiments where neutrons are used in research reactors for seed irradiation it is difficult to measure the dose accurately and therefore to establish significant comparisons between experimental results obtained in various reactors and between repeated experiments in the same reactor. A further obstacle lies in the nature and response of the seeds themselves and the variety of ways in which they are exposed in reactors. The International Atomic Energy Agency decided to initiate international efforts to improve and standardize methods of exposing seeds in research reactors and of measuring and reporting the neutron dose. For this purpose, an International Neutron Seed Irradiation Programme has been established. The present report aims to give a brief but comprehensive picture of the work so far done in this programme. Refs, figs and tabs

  14. Design, construction and installation of an epithermal neutron beam for BNCT at the High Flux Reactor Petten

    International Nuclear Information System (INIS)

    Following the formation in 1987, of both the European Collaboration group on Boron Neutron Capture Therapy (BNCT) and the Petten BNCT group, steps were taken to design and implement an epithermal neutron beam for BNCT applications at the High Flux Reactor (HFR) at Petten. The installation would serve as a European facility, while once the modality of BNCT is proven would be the pathfinder for implementation of BNCT at other European nuclear sites. Due to its favorable nuclear and geometric characteristics, the beam tube HB11 was chosen as the candidate beam tube for BNCT applications. To reconfigure the beam tube to produce the required epithermal neutrons, it was first necessary to remove the existing mirror system and then to install the appropriate filter materials. Due to the fixed operating schedule of the HFR, with only one long shut-down period per year during the summer weeks for maintenance and upgrading actions, installation of the new facility was planned for the summer stop period in 1990

  15. Collimator and shielding design for boron neutron capture therapy (BNCT) facility at TRIGA MARK II reactor

    International Nuclear Information System (INIS)

    The geometry of reactor core, thermal column, collimator and shielding system for BNCT application of TRIGA MARK II Reactor were simulated with MCNP5 code. Neutron particle lethargy and dose were calculated with MCNPX code. Neutron flux in a sample located at the end of collimator after normalized to measured value (Eid Mahmoud Eid Abdel Munem, 2007) at 1 MW power was 1.06 x 108 n/ cm2/ s. According to IAEA (2001) flux of 1.00 x 109 n/ cm2/ s requires three hours of treatment. Few modifications were needed to get higher flux. (Author)

  16. A study of neutron fluence rates of the BNCT beam at THOR using foil activation

    International Nuclear Information System (INIS)

    Neutron fluence rates of the BNCT epithermal neutron beam at THOR were measured by using double-foil activation method free-in-air and in a water phantom. Foil sets consisting of gold, copper and manganese were used for measurements. Copper was used as an extra detector for quality check. Monte Carlo calculations using the MCNP4C code were conducted to support and compare with the measurement results. It was found that the calculation of reaction rates of foils free-in-air based on a neutron source with a coarse group energy structure is inadequate. The meetness of the assumptions on the neutron energy distribution made in the double-foil formulation for the determination of neutron fluence rates must be estimated in order to compare with the calculation. (author)

  17. Boron determination in liver tissue by combining quantitative neutron capture radiography (QNCR) and histological analysis for BNCT treatment planning at the TRIGA Mainz.

    Science.gov (United States)

    Schütz, C; Brochhausen, C; Altieri, S; Bartholomew, K; Bortolussi, S; Enzmann, F; Gabel, D; Hampel, G; Kirkpatrick, C J; Kratz, J V; Minouchehr, S; Schmidberger, H; Otto, G

    2011-09-01

    The typical primary malignancies of the liver are hepatocellular carcinoma and cholangiocarcinoma, whereas colorectal liver metastases are the most frequently occurring secondary tumors. In many cases, only palliative treatment is possible. Boron neutron capture therapy (BNCT) represents a technique that potentially destroys tumor tissue selectively by use of externally induced, locally confined secondary particle irradiation. In 2001 and 2003, BNCT was applied to two patients with colorectal liver metastases in Pavia, Italy. To scrutinize the rationale of BNCT, a clinical pilot study on patients with colorectal liver metastases was carried out at the University of Mainz. The distribution of the (10)B carrier (p-borono-phenylalanine) in the liver and its uptake in cancerous and tumor-free tissue were determined, focusing on a potential correlation between the uptake of p-borono-phenylalanine and the biological characteristics of cancerous tissue. Samples were analyzed using quantitative neutron capture radiography of cryosections combined with histological analysis. Methodological aspects of the combination of these techniques and results from four patients enrolled in the study are presented that indicate that the uptake of p-borono-phenylalanine strongly depends on the metabolic activity of cells. PMID:21692653

  18. Correlation between radiation dose and histopathological findings in patients with gliblastoma treated with boron neutron capture therapy (BNCT)

    International Nuclear Information System (INIS)

    The purpose of this study was to clarify the correlation between the radiation dose and histopathological findings in patients with glioblastoma multiforme (GBM) treated with boron neutron capture therapy (BNCT). Histopathological studies were performed on specimens from 8 patients, 3 had undergone salvage surgery and 5 were autopsied. For histopathological cure of GBM at the primary site, the optimal minimal dose to the gross tumor volume (GTV) and the clinical target volume (CTV) were 68 Gy(w) and 44 Gy(w), respectively. - Highlights: • It is very important to determine the curable BNCT radiation dose on histopathological aspect in BNCT. • Of 23 patients with GBM treated with BNCT, autopsy was performed in 5, salvage surgery in 3, and histopathological study in 8. • To achieve the histopathological cure of GBM at the primary site, the optimal minimal dose to the GTV and CTV was 68 Gy(w) and 44 Gy(w), respectively

  19. Gel dosimeters as useful dose and thermal-fluence detectors in Boron Neutron Capture Therapy (BNCT)

    International Nuclear Information System (INIS)

    The dosimetry method based on Fricke-Xylenol-Orange-infused gels in form of layers has shown noticeable potentiality for in-phantom or in-free-beam dose and thermal flux profiling and imaging in the high fluxes of thermal or epithermal neutrons utilised for boron neutron capture therapy (BNCT). Gel-dosimeters in form of layers give the possibility not only of obtaining spatial dose distributions but also of achieving measurements of each dose contribution in neutron fields. The discrimination of the various dose components is achieved by means of pixel-to-pixel manipulations of pairs of images obtained with gel-dosimeters having different isotopic composition. It is possible to place large dosimeters, detecting in such a way large dose images, because the layer geometry of dosimeters avoids sensitive variation of neutron transport due to the gel isotopic composition. Some results obtained after the last improvements of the method are reported. (Author)

  20. Gel dosimeters as useful dose and thermal-fluence detectors in Boron Neutron Capture Therapy (BNCT)

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G.; Valente, M. [Department of Physics of the University and INFN, Via Celoria 16, I-20133 Milan (Italy); Moss, R.L.; Daquino, G.G.; Nievaart, V.A. [Joint Research Centre, Institute for Energy, P.O. Box 2, NL-1755ZG Petten, The Netherlands (Netherlands); Mariani, M.; Vanossi, E. [Department of Nuclear Engineering of Polytechnic, CESNEF, Via Ponzio, 34/3 - I-20133 Milan (Italy); Carrara, M. [Medical Physics Department, National Cancer Institute, Via Venezian 1, I-20131, Milan (Italy)

    2006-07-01

    The dosimetry method based on Fricke-Xylenol-Orange-infused gels in form of layers has shown noticeable potentiality for in-phantom or in-free-beam dose and thermal flux profiling and imaging in the high fluxes of thermal or epithermal neutrons utilised for boron neutron capture therapy (BNCT). Gel-dosimeters in form of layers give the possibility not only of obtaining spatial dose distributions but also of achieving measurements of each dose contribution in neutron fields. The discrimination of the various dose components is achieved by means of pixel-to-pixel manipulations of pairs of images obtained with gel-dosimeters having different isotopic composition. It is possible to place large dosimeters, detecting in such a way large dose images, because the layer geometry of dosimeters avoids sensitive variation of neutron transport due to the gel isotopic composition. Some results obtained after the last improvements of the method are reported. (Author)

  1. Dose estimation of the THOR BNCT treatment room

    International Nuclear Information System (INIS)

    BNCT beam of Tsing Hua Open-pool Reactor (THOR) was designed and constructed since 1998. A treatment room for the newly modified THOR BNCT beam was constructed for the next clinical-stage trials in 2004. Dose distribution in a patient (or a phantom) is important as irradiated with the BNCT beam. The dose distributions for different type of radiations such as neutron and photons in the treatment room are strongly becoming the index or reference of success for a BNCT facility. An ART head phantom was placed in front of the THOR BNCT beam port and was irradiated. In each section of the head phantom, numbers of small holes are inside and separated uniformly. Dual detector: TLD-600 and TLD-700 chips were placed inside these holes within the phantom to distinct doses of neutron and photon. Besides, Dual-TLD chips were latticed placed in the horizontal plane of beam central axis, in the treatment room to estimate the spatial dose distribution of neutron and photon. Gold foils were assisted in TLD dose calibrations. Neutron and photon dose distributions in phantom and spatial dose distributions in the THOR BNCT treatment room were both estimated in this work. Testing and improvement in THOR BNCT beam were continuative during these years. Results of this work could be the reference and be helpful for the further clinical trials in nearly future. (author)

  2. 9Be(d,n)10B-based neutron sources for BNCT

    International Nuclear Information System (INIS)

    In the frame of accelerator-based BNCT, the 9Be(d,n)10B reaction was investigated as a possible source of epithermal neutrons. In order to determine the configuration in terms of bombarding energy, target thickness and Beam Shaping Assembly (BSA) design that results in the best possible beam quality, a systematic optimization study was carried out. From this study, the optimal configuration resulted in tumor doses ≥40 Gy-Eq, with a maximum value of 51 Gy-Eq at a depth of about 2.7 cm, in a 60 min treatment. The optimal configuration was considered for the treatment planning assessment of a real Glioblastoma Multiforme case. From this, the resulted dose performances were comparable to those obtained with an optimized 7Li(p,n)-based neutron source, under identical conditions and subjected to the same clinical protocol. - Highlights: • Study of the 9Be(d,n)10B reaction as a source of epithermal neutrons for BNCT. • Evaluation of the optimal configuration of target thickness, deuteron energy and BSA design. • Computational dose assessment for brain tumor treatments using the MCNP code. • Treatment planning assessment of a particular clinical Glioblastoma Multiforme case. • Dose performances were comparable to those obtained with an optimized 7Li(p,n)-based source

  3. Neutron spectra measurement and comparison of the HFR and THOR BNCT beams

    International Nuclear Information System (INIS)

    This paper aims to measure the spectra of HB11 (high flux reactor, HFR) and the Tsing Hua open-pool reactor (THOR) boron neutron capture therapy (BNCT) beams by multiple activation foils. The self-shielding corrections were made with the aid of MCNP calculations. The initial spectra were adjusted by a sophisticated process named coarse-scaling adjustment using SAND-EX, which can adjust a given coarse-group spectrum into a fine-group structure, i.e. 640 groups, with excellent continuity. The epithermal neutron flux of the THOR beam is about three times of HB11. The thermal neutron flux, boron and gold reaction rates along the central axis of a PMMA phantom are calculated for both adjusted spectra for comparison.

  4. Gamma residual radioactivity measurements on rats and mice irradiated in the thermal column of a TRIGA Mark II reactor for BNCT.

    Science.gov (United States)

    Protti, Nicoletta; Manera, Sergio; Prata, Michele; Alloni, Daniele; Ballarini, Francesca; di Tigliole, Andrea Borio; Bortolussi, Silva; Bruschi, Piero; Cagnazzo, Marcella; Garioni, Maria; Postuma, Ian; Reversi, Luca; Salvini, Andrea; Altieri, Saverio

    2014-12-01

    The current Boron Neutron Capture Therapy (BNCT) experiments performed at the University of Pavia, Italy, are focusing on the in vivo irradiations of small animals (rats and mice) in order to evaluate the effectiveness of BNCT in the treatment of diffused lung tumors. After the irradiation, the animals are manipulated, which requires an evaluation of the residual radioactivity induced by neutron activation and the relative radiological risk assessment to guarantee the radiation protection of the workers. The induced activity in the irradiated animals was measured by high-resolution open geometry gamma spectroscopy and compared with values obtained by Monte Carlo simulation. After an irradiation time of 15 min in a position where the in-air thermal flux is about 1.2 × 10(10) cm(-2) s(-1), the specific activity induced in the body of the animal is mainly due to 24Na, 38Cl, 42K, 56Mn, 27Mg and 49Ca; it is approximately 540 Bq g(-1) in the rat and around 2,050 Bq g(-1) in the mouse. During the irradiation, the animal body (except the lung region) is housed in a 95% enriched 6Li shield; the primary radioisotopes produced inside the shield by the neutron irradiation are 3H by the 6Li capture reaction and 18F by the reaction sequence 6Li(n,α)3H → 16O(t,n)18F. The specific activities of these products are 3.3 kBq g(-1) and 880 Bq g(-1), respectively. PMID:25353239

  5. Application of HVJ envelope system to boron neutron capture therapy (BNCT)

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy (BNCT) has been used clinically for the treatment of malignant tumors. Two drugs, p-boronophenylalanine (BPA) and sulfhydral borane (BSH), have been used as boron delivery agents. These drugs seem to be taken up preferentially in solid tumors, but it is uncertain whether therapeutic quantities of boron atoms are taken up by micro-invasive or distant tumor cells. High accumulation and high selective delivery of boron into tumor tissues are the most important requirements to achieve efficient BNCT for malignant tumor. The HVJ envelope (HVJ-E) vector system is a novel fusion-mediated gene delivery system based on inactivated hemagglutinating virus of Japan (HVJ; Sendai virus). Although we developed this vector system for gene transfer, it can also deliver proteins, synthetic oligonucleotides, and drugs. HVJ-liposome, which is liposome fused with HVJ-E, has higher boron trapping efficiency than HVJ-E alone. We report the boron delivery into cultured cells with HVJ-liposome systems. The cellular 10B concentration after 60 min incubation with HVJ-E containing BSH was 24.9 μg/g cell pellet for BHK-21 cells (baby hamster kidney cells) and 19.4 μg/g cell pellet for SCC VII cells (murine squamous cell carcinoma). These concentrations are higher than that of 60 min incubated cells with BSH containing (100μg 10B/ml) medium. These results indicate the HVJ-E fused with tumor cell membrane and rapidly delivered boron agents, and that the HVJ-E-mediated delivery system could be applicable to BNCT. Plans are underway to begin neutron radiation experiments in vivo and in vitro. (author)

  6. JRR-4 medical irradiation facility

    Energy Technology Data Exchange (ETDEWEB)

    Torii, Y.; Yamamoto, K.; Hori, N.; Kumada, H.; Horiguchi, Y. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-11-01

    JAERI started Boron Neutron Capture Therapy (BNCT) at JRR-2 in 1990. JRR-2 was performed 33 BNCT until 1996 when JRR-2 operation was terminated for decommissioning the reactor. JRR-4 was constructed to research the reactor shielding of the first Japanese nuclear ship ''Mutsu'' in 1965. JRR-4 was modified for reducing fuel enrichment and constructing a new medical irradiation facility at 1997 when after the terminating operation of JRR-2. The medical irradiation facility is especially using for BNCT of brain cancer. JRR-4 medical irradiation facility was designed for both using of thermal neutron beam and epi-thermal neutron. Thermal neutron is using for conventional Japanese BNCT as inter operative irradiation therapy. Epi-thermal neutron beam will be using advanced BNCT for deep cancer and without craniotomy operation for irradiation at the facility. The first medical irradiation for BNCT of JRR-4 was carried out on October 25, 1999. Since then, seven times of irradiation was performed by the end of June 2000. In BNCT irradiation, boron concentration and thermal flux measurements were performed by JAERI. Boron concentration of patient brood was measured using prompt gamma ray analysis technique. Thermal neutron flux was measured by gold wire activation method using beta - gamma coincidence counting system. There data were furnished to medical doctor for determination the irradiation time of BNCT. (author)

  7. Neutron beam experiments using nuclear research reactors: honoring the retirement of professor Bernard W. Wehring -I. 3. A Comparison of Neutron Beams for BNCT

    International Nuclear Information System (INIS)

    spheres (0.2-cm radius) located ∼0.1 cm apart along the phantom centerline. To reduce the computational time required to obtain flux values with acceptable errors (fractional uncertainty ·n, D·γ, and d·B as a function of depth in the phantom were fit with curves using the Kaleidagraph software package on the Macintosh computer. The resulting curve fits were used to calculate T and DTumor. The point of view that we have adopted in designing an ABNS for BNCT is that glioblastoma multiform is a whole-brain disease and that recurrences are most likely to arise in the tumor margins that receive the least dose. For a bilateral irradiation, this corresponds to the midline of the brain, and hence, in designing an ABNS for BNCT, we have considered the value of DTumor at 7 cm to be most important since the phantom that we used in our analysis has an axial thickness of 14 cm. The value of DTumor, at a depth of 7 cm, is presented for each neutron source along with the treatment time T. A major goal of our analysis was to determine if a 500-kW reactor with an FCP can produce a neutron field with sufficient intensity to allow a patient to be treated in an acceptable treatment time with adequate beam quality. According to our analysis, the answer to this question is 'yes', provided that the patient is treated with at least four fractions. Although the quality of the neutron field for the OSURR-FCP is slightly inferior to the quality of the neutron field for the OSU-ABNS, the neutron field quality of the OSURR-FCP is judged to be acceptable, on the basis of comparison with DTumor at a depth of 7 cm for the BMRR-ENB. (authors)

  8. On-line neutron beam monitoring of the Finnish BNCT facility

    International Nuclear Information System (INIS)

    A Boron Neutron Capture Therapy (BNCT) facility has been built at the FiR 1 research reactor of VTT Chemical Technology in Espoo, Finland. The facility is currently undergoing dosimetry characterisation and neutron beam operation research for clinical trials. The healthy tissue tolerance study, which was carried out in the new facility during spring 1998, demonstrated the reliability and user-friendliness of the new on-line beam monitoring system designed and constructed for BNCT by VTT Chemical Technology. The epithermal neutron beam is monitored at a bismuth gamma shield after an aluminiumfluoride-aluminium moderator. The detectors are three pulse mode U235-fission chambers for epithermal neutron fluence rate and one current mode ionisation chamber for gamma dose rate. By using different detector sensitivities the beam intensity can be measured over a wide range of reactor power levels (0.001-250 kW). The detector signals are monitored on-line with a virtual instrumentation (LabView) based PC-program, which records and displays the actual count rates and total counts of the detectors in the beam. Also reactor in-core power instrumentation and control rod positions can be monitored via another LabView application. The main purpose of the monitoring system is to provide a dosimetric link to the dose in a patient during the treatment, as the fission chamber count rates have been calibrated to the induced thermal neutron fluence rate and to the absorbed dose rate at reference conditions in a tissue substitute phantom

  9. On-line neutron beam monitoring of the Finnish BNCT facility

    Science.gov (United States)

    Tanner, Vesa; Auterinen, Iiro; Helin, Jori; Kosunen, Antti; Savolainen, Sauli

    1999-02-01

    A Boron Neutron Capture Therapy (BNCT) facility has been built at the FiR 1 research reactor of VTT Chemical Technology in Espoo, Finland. The facility is currently undergoing dosimetry characterisation and neutron beam operation research for clinical trials. The healthy tissue tolerance study, which was carried out in the new facility during spring 1998, demonstrated the reliability and user-friendliness of the new on-line beam monitoring system designed and constructed for BNCT by VTT Chemical Technology. The epithermal neutron beam is monitored at a bismuth gamma shield after an aluminiumfluoride-aluminium moderator. The detectors are three pulse mode U 235-fission chambers for epithermal neutron fluence rate and one current mode ionisation chamber for gamma dose rate. By using different detector sensitivities the beam intensity can be measured over a wide range of reactor power levels (0.001-250 kW). The detector signals are monitored on-line with a virtual instrumentation (LabView) based PC-program, which records and displays the actual count rates and total counts of the detectors in the beam. Also reactor in-core power instrumentation and control rod positions can be monitored via another LabView application. The main purpose of the monitoring system is to provide a dosimetric link to the dose in a patient during the treatment, as the fission chamber count rates have been calibrated to the induced thermal neutron fluence rate and to the absorbed dose rate at reference conditions in a tissue substitute phantom.

  10. Boron delivery with liposomes for boron neutron capture therapy (BNCT): biodistribution studies in an experimental model of oral cancer demonstrating therapeutic potential

    Energy Technology Data Exchange (ETDEWEB)

    David W. Nigg

    2012-05-01

    Boron neutron capture therapy (BNCT) combines selective accumulation of 10B carriers in tumor tissue with subsequent neutron irradiation. We previously demonstrated the therapeutic efficacy of BNCT in the hamster cheek pouch oral cancer model. Optimization of BNCT depends largely on improving boron targeting to tumor cells. Seeking to maximize the potential of BNCT for the treatment for head and neck cancer, the aim of the present study was to perform boron biodistribution studies in the oral cancer model employing two different liposome formulations that were previously tested for a different pathology, i.e., in experimental mammary carcinoma in BALB/c mice: (1) MAC: liposomes incorporating K[nido-7-CH3(CH2)15-7,8-C2B9H11] in the bilayer membrane and encapsulating a hypertonic buffer, administered intravenously at 6 mg B per kg body weight, and (2) MAC-TAC: liposomes incorporating K[nido-7-CH3(CH2)15-7,8-C2B9H11] in the bilayer membrane and encapsulating a concentrated aqueous solution of the hydrophilic species Na3 [ae-B20H17NH3], administered intravenously at 18 mg B per kg body weight. Samples of tumor, precancerous and normal pouch tissue, spleen, liver, kidney, and blood were taken at different times post-administration and processed to measure boron content by inductively coupled plasma mass spectrometry. No ostensible clinical toxic effects were observed with the selected formulations. Both MAC and MAC-TAC delivered boron selectively to tumor tissue. Absolute tumor values for MAC-TAC peaked to 66.6 {+-} 16.1 ppm at 48 h and to 43.9 {+-} 17.6 ppm at 54 h with very favorable ratios of tumor boron relative to precancerous and normal tissue, making these protocols particularly worthy of radiobiological assessment. Boron concentration values obtained would result in therapeutic BNCT doses in tumor without exceeding radiotolerance in precancerous/normal tissue at the thermal neutron facility at RA-3.

  11. Epithermal neutron beam for BNCT research at Washington State University

    International Nuclear Information System (INIS)

    A new filter has been designed and analysed for the Washington State University TRIGATM research reactor. Optimum balance of epithermal flux and background KERMA was obtained with a FluentalTM and alumina filter. The epithermal neutron flux calculated by the DORT transport code was approximately 9 x 108 n/cm2-s with a background KERMA of about 3x10-13 Gy/n/cm2. Operation of the beam for animal testing is expected to commence in 2000. (author)

  12. Quality assurance of BNCT dosimetry

    International Nuclear Information System (INIS)

    The Phase I clinical trials for boron neutron capture therapy (BNCT) started in May 1999 in Otaniemi, Espoo. For BNCT no uniform international guidance for the quality assurance of dosimetry exists, so far. Because of the complex dose distribution with several different dose components, the international recommendations on conventional radiotherapy dosimetry are not applicable in every part. Therefore, special guidance specifically for BNCT is needed. To obtain such guidelines a European collaboration project has been defined. The aim of the project is a generally accepted Code of Practice for use by all European BNCT centres. This code will introduce the traceability of the dosimetric methods to the international measurement system. It will also ensure the comparability of the results in various BNCT beams and form the basis for the comparison of the treatment results with the conventional radiotherapy or other treatment modalities. The quality assurance of the dosimetry in BNCT in Finland covers each step of the BNCT treatment, which include dose planning imaging, dose planning, boron infusion, boron kinetics, patient positioning, monitoring of the treatment beam, characterising the radiation spectrum, calibration of the beam model and the dosimetric measurements both in patients (in viva measurements) and in various phantoms. The dose planning images are obtained using a MR scanner with MRI sensitive markers and the dose distribution is computed with a dose planning software BNCTRtpe. The program and the treatment beam (DORT) model used have been verified with measurements and validated with MCNP calculations in phantom. Dosimetric intercomparison has been done with the Brookhaven BNCT beam (BMRR). Before every patient irradiation the relationship between the beam monitor pulse rate and neutron fluence rate in the beam is checked by activation measurements. Kinetic models used to estimate the time-behavior of the blood boron concentration have been verified

  13. Neutron irradiation effect of silicon

    International Nuclear Information System (INIS)

    Several kinds of silicon wafers were irradiated at four neutron fields with different energy spectra. Electrical resistivity and deep level defect concentrations after the neutron irradiation, and their changes against number of displacement atoms (DPA's) for different neutron fields were compared. The number of DPA's was calculated by N. Yamano's data. (author)

  14. Thermal neutron irradiation field design for boron neutron capture therapy of human explanted liver.

    Science.gov (United States)

    Bortolussi, S; Altieri, S

    2007-12-01

    The selective uptake of boron by tumors compared to that by healthy tissue makes boron neutron capture therapy (BNCT) an extremely advantageous technique for the treatment of tumors that affect a whole vital organ. An example is represented by colon adenocarcinoma metastases invading the liver, often resulting in a fatal outcome, even if surgical resection of the primary tumor is successful. BNCT can be performed by irradiating the explanted organ in a suitable neutron field. In the thermal column of the Triga Mark II reactor at Pavia University, a facility was created for this purpose and used for the irradiation of explanted human livers. The neutron field distribution inside the organ was studied both experimentally and by means of the Monte Carlo N-particle transport code (MCNP). The liver was modeled as a spherical segment in MCNP and a hepatic-equivalent solution was used as an experimental phantom. In the as-built facility, the ratio between maximum and minimum flux values inside the phantom ((phi(max)/phi(min)) was 3.8; this value can be lowered to 2.3 by rotating the liver during the irradiation. In this study, the authors proposed a new facility configuration to achieve a uniform thermal neutron flux distribution in the liver. They showed that a phi(max)/phi(min) ratio of 1.4 could be obtained without the need for organ rotation. Flux distributions and dose volume histograms were reported for different graphite configurations. PMID:18196797

  15. Design of a BNCT facility at HANARO

    International Nuclear Information System (INIS)

    Based on the feasibility study of the BNCT at HANARO, it was confirmed that only thermal BNCT is possible at the IR beam tube if appropriate filtering system be installed. Medical doctors in Korea Cancer Center Hospital agreed that the thermal BNCT facility would be worthwhile for the BNCT technology development in Korea as well as superficial cancer treatment. For the thermal BNCT to be effective, the thermal neutron flux should be high enough for patient treatment during relatively short time and also the fast neutron and gamma-ray fluxes should be as low as possible. In this point of view, the following design requirements are set up: 1) thermal neutron flux at the irradiation position should be higher than 3x109 n/cm2-sec, 2) ratio of the fast neutrons and gamma-rays to the thermal neutrons should be minimized, and 3) patient treatment should be possible without interrupt to the reactor operation. To minimize the fast neutrons and gamma-rays with the required thermal neutrons at the irradiation position, a radiation filter consisting of single crystals of silicon and bismuth at liquid nitrogen temperature is designed. For the shielding purpose around the irradiation position, polyethylene, lead, LiF, etc., are appropriately arranged around the radiation filter. A water shutter in front of the radiation filter is adopted so as to avoid interrupt to the reactor operation. At present, detail design of the radiation filter is ongoing. Cooling capabilities of the filter will be tested through a mockup experiment. Dose rate distributions around the radiation filter and a prompt gamma-ray activation analysis system for the analyses of boron content in the biological samples are under design. The construction of this facility will be started from next year if it is permitted from the regulatory body this year. Some other future works exist and are described in the paper. (author)

  16. Renovation of epithermal neutron beam for BNCT at THOR

    International Nuclear Information System (INIS)

    Heading for possible use for clinical trial, THOR (Tsing Hua Open-pool Reactor) at Taiwan was shutdown for renovation of a new epithermal neutron beam in January 2003. In November 2003, concrete cutting was finished for closer distance from core and larger treatment room. This article presents the design base that the construction of the new beam is based on. The filter/moderator design along the beam is Cd(0.1 cm)+Al(10 cm)+FLUENTALTM(16 cm)+Al(10 cm)+FLUENTAL(24 cm)+Void(18 cm)+Cd(0.1 cm)+Bi(10 cm) with 6 cm Pb as reflector. Following the filter/moderator is an 88 cm long, 6 cm thick Bi-lined collimator with Li2CO3-PE at the end. The collimator is surrounded by Li2CO3-PE and Pb. The calculated beam parameters under 2 MW at the beam exit is phiepi=3.4x109 n/cm2/s, Df/phiepi=2.8x10-11 cGy cm2/n, Dγ/phiepi=1.3x10-11 cGy cm2/n, and J+/phi= 0.8. For a phantom placed 10 cm from beam exit, MCNP calculation shows that the advantage depth is 8.9 cm, and advantage ratio is 5.6 if boron concentration in tumor and normal tissue are assumed to be 65 and 18 ppm. The maximum dose rate for normal tissue is 50 cGy/min. The maximum therapeutic ratio is 6. The construction of the beam is scheduled to be finished by the end of April 2004

  17. On the 252Cf primary and secondary gamma rays and epithermal neutron flux for BNCT

    Science.gov (United States)

    Ghassoun, J.; Merzouki, A.; El Morabiti, A.; Jehouani, A.

    2007-10-01

    Monte Carlo simulation has been used to calculate the different components of neutrons and secondary gamma rays originated by 252Cf fission and also the primary gamma rays emitted directly by the 252Cf source at the exit face of a compact system designed for the BNCT. The system consists of a 252Cf source and a moderator/reflector/filter assembly. To study the material properties and configuration possibilities, the MCNP code has been used. The moderator/reflector/filter arrangement is optimised to moderate neutrons to epithermal energy and, as far as possible, to get rid of fast and thermal neutrons and photons from the therapeutic beam. To reduce the total gamma contamination and to have a sufficiently high epithermal neutron flux we have used different photon filters of different thickness. Our analysis showed that the use of an appropriate filter leads to a gamma ray flux reduction without affecting the epithermal neutron beam quality at the exit face of the system.

  18. On the {sup 252}Cf primary and secondary gamma rays and epithermal neutron flux for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Ghassoun, J. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco)], E-mail: ghassoun@ucam.ac.ma; Merzouki, A. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco); Remote Sensing and Geomatics of the Environnement Laboratory, Ottawa-Carleton Geoscience Centre, Marion Hall-140Louis Pasteur Ottawa, ON, KIN 6N5 (Canada); El Morabiti, A.; Jehouani, A. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco)

    2007-10-15

    Monte Carlo simulation has been used to calculate the different components of neutrons and secondary gamma rays originated by {sup 252}Cf fission and also the primary gamma rays emitted directly by the {sup 252}Cf source at the exit face of a compact system designed for the BNCT. The system consists of a {sup 252}Cf source and a moderator/reflector/filter assembly. To study the material properties and configuration possibilities, the MCNP code has been used. The moderator/reflector/filter arrangement is optimised to moderate neutrons to epithermal energy and, as far as possible, to get rid of fast and thermal neutrons and photons from the therapeutic beam. To reduce the total gamma contamination and to have a sufficiently high epithermal neutron flux we have used different photon filters of different thickness. Our analysis showed that the use of an appropriate filter leads to a gamma ray flux reduction without affecting the epithermal neutron beam quality at the exit face of the system.

  19. On the 252Cf primary and secondary gamma rays and epithermal neutron flux for BNCT

    International Nuclear Information System (INIS)

    Monte Carlo simulation has been used to calculate the different components of neutrons and secondary gamma rays originated by 252Cf fission and also the primary gamma rays emitted directly by the 252Cf source at the exit face of a compact system designed for the BNCT. The system consists of a 252Cf source and a moderator/reflector/filter assembly. To study the material properties and configuration possibilities, the MCNP code has been used. The moderator/reflector/filter arrangement is optimised to moderate neutrons to epithermal energy and, as far as possible, to get rid of fast and thermal neutrons and photons from the therapeutic beam. To reduce the total gamma contamination and to have a sufficiently high epithermal neutron flux we have used different photon filters of different thickness. Our analysis showed that the use of an appropriate filter leads to a gamma ray flux reduction without affecting the epithermal neutron beam quality at the exit face of the system

  20. Stability of high-speed lithium sheet jets for the neutron source in Boron Neutron Capture Therapy (BNCT)

    International Nuclear Information System (INIS)

    The stability of high-speed liquid lithium sheet jets was analytically studied for the neutron source in Boron Neutron Capture Therapy (BNCT), which makes cancers and tumors curable with cell-level selections and hence high QOL. The object of our research is to realize the thin and high-speed plane sheet jets of liquid lithium in a high-vacuum as an accelerator target. Linear analysis approach is made to the stability on thin plane sheet jets of liquid lithium in a high-vacuum, and then our analytical results were compared with the previous experimental ones. We proved that the waves of surface tension on thin lithium sheet jets in a high-vacuum are of supercritical flows and neutral stable under about 17.4 m/s in flow velocity and that the fast non-dispersive anti-symmetric waves are more significant than the very slow dispersive symmetric waves. We also formulated the equation of shrinking angle in isosceles-triangularly or isosceles-trapezoidal shrinking sheet jets corresponding to the Mach angle of supersonic gas flows. This formula states universally the physical meaning of Weber number of sheet jets on the wave of surface tension in supercritical flows. We obtained satisfactory prospects (making choice of larger flow velocity U and larger thickness of sheet a) to materialize a liquid target of accelerator in BNCT. (author)

  1. Design study of multi-imaging plate system for BNCT irradiation field at Kyoto university reactor.

    Science.gov (United States)

    Tanaka, Kenichi; Sakurai, Yoshinori; Kajimoto, Tsuyoshi; Tanaka, Hiroki; Takata, Takushi; Endo, Satoru

    2016-09-01

    The converter configuration for a multi-imaging plate system was investigated for the application of quality assurance in the irradiation field profile for boron neutron capture therapy. This was performed by the simulation calculation using the PHITS code in the fields at the Heavy Water Neutron Irradiation Facility of Kyoto University Reactor. The converter constituents investigated were carbon for gamma rays, and polyethylene with and without LiF at varied (6)Li concentration for thermal, epithermal, and fast neutrons. Consequently, potential combinations of the converters were found for two components, gamma rays and thermal neutrons, for the standard thermal neutron mode and three components of gamma rays, epithermal neutrons, and thermal or fast neutrons, for the standard mixed or epithermal neutron modes, respectively. PMID:27423022

  2. Clinical results of BNCT for malignant meningiomas

    International Nuclear Information System (INIS)

    Malignant meningiomas is difficult pathology to be controlled as well as GBM. Since June of 2005, we applied BNCT for 7 cases of malignancy related meningiomas with 13 times neutron irradiation. Five were anaplastic, one was atypical meningiomas and one was sarcoma transformed from meningioma with cervical lymph node metastasis. All cases were introduced after repetitive surgeries and XRT or SRS. Follow-up images were available for 6 cases with observation duration between 2 to 9 months. We applied F-BPA-PET before BNCT in 6 out of 7 cases. One case was received methionine-PET. Five out of 6 cases who received BPA-PET study showed good BPA uptake more than 3 of T/N ratio. One atypical meningiomas cases showed 2.0 of T/N ratio. Original tumor sizes were between 9.2 to 92.7 ml. Two out of 5 anaplastic meningiomas showed CR and all six cases showed radiographic improvements. Clinical symptoms before BNCT such as hemiparesis and facial pain were improved after BNCT, except one case. An huge atypical meningiomas which arisen from tentorium and extended bilateral occipital lobes and brain stem, visual problems were worsened after repetitive BNCT with increase of peritumoral edema. Malignant meningiomas are seemed to be good candidate for BNCT. (author)

  3. Neutron flux measurements with Monte Carlo verification at the thermal column of a TRIGA MARK II reactor: Feasibility study for a BNCT facility

    International Nuclear Information System (INIS)

    The treatment of the malignant brain tumor through Boron Neutron Capture Therapy (BNCT) requires a high-flux neutron source. The Malaysian TRIGA Mark II reactor was investigated for a proposed BNCT facility. The neutron flux was measured along the central stringer of the thermal column and the outermost positions of the other stringers. The unfolding foil method was applied here. We have used Al, As, Au, Co, In, Mo, Ni and Re foils and Cd as a cover with 19 useful reactions in this study. The infinitely diluted foil activity was calculated and used in the SAND-II code (Spectrum Analysis by Neutron Detectors) to calculate the neutron flux. The reactor was also simulated using Monte Carlo code (MCNP5) and the neutron flux was calculated along the thermal column. The measured and calculated neutron flux along the thermal column show good agreement. The minimum epithermal neutron intensity required for BNCT is achieved up to position 22 with a mixed neutron-gamma beam. A suggested MCNP simulated modification of the reactor thermal column increased the neutron flux at distant positions from the reactor core but the epithermal neutron part was below the minimum requirement for a BNCT facility. The photon flux calculations along the thermal column show relatively high results which should be filtered. The calculation of the neutron and gamma dose in a head phantom (water) indicated that the available neutron spectrum requires modifications to increase the epithermal part of the neutrons and filter the gamma ray contamination. (author)

  4. Physical engineering and medical physics on boron neutron capture therapy

    International Nuclear Information System (INIS)

    The contents of physical engineering and medical physics that support boron neutron capture therapy (BNCT) can be roughly classified to the four items, (1) neutron irradiation system, (2) development and improvement of dose assessment techniques, (3) development and improvement of dose planning system, and (4) quality assurance and quality control. This paper introduces the BNCT at Kyoto University Research Reactor Institute, with a focus on the basic physics of BNCT, thermal neutron irradiation and epithermal neutron irradiation, heavy water neutron irradiation facilities of KUR, and medical irradiation system of KUR. It also introduces the world's first BNCT clinical cyclotron irradiation system (C-BENS) of Kyoto University Research Reactor Institute, BNCT dose assessment techniques, dose planning system, and quality assurance and quality control. (A.O.)

  5. Boron neutron capture irradiation: setting up a clinical programme in Nice; Irradiation par capture de neutrons: mise en place d`un programme clinique a Nice

    Energy Technology Data Exchange (ETDEWEB)

    Pignol, J.P.; Chauvel, P.; Courdi, A.; Iborra-Brassart, N.; Frenay, M.; Herault, J.; Bensadoun, R.J.; Milano, G.; Demard, F. [Centre de Lutte Contre le Cancer Antoine Lacassagne, 06 - Nice (France); Paquis, P.; Lonjon, M.; Lebrun-Frenay, C.; Grellier, P.; Chatel, M. [Hopital Pasteur, 06 - Nice (France); Nepveu, F.; Patau, J.P. [Toulouse-3 Univ., 31 (France); Breteau, N. [Hopital de la Source, 45 - Orleans (France)

    1996-12-31

    Neutron capture irradiation aims to selectively destroy tumor tumor cell using {sup 10}B(n,{alpha}){sup 7}Li nuclear reactions produced within themselves. Following the capture reaction, an {alpha} particle and a, {sup 7}Li ion are emitted. Carrying an energy of 2.79 MeV, they destroy all molecular structures along their path close to 10 {mu}m. These captures, used exclusively with a `slow` neutron irradiation, provide a neutron capture therapy (BNCT). If they are used in addition to a fast neutron beam irradiation, they provide a neutron capture potentiation (NCP). The Centre Antoine-Lacassagne in Nice is actively involved in the European Demonstration project for BNCT of grade IV glioblastomas (GBM) after surgical excision and BSH administration. Taking into account the preliminary results obtained in Japan, work on an `epithermal` neutron target compatible with various cyclotron beams is in progress to facilitate further developments of this technique. For NCP, thermalized neutron yield has been measured in phantoms irradiated in the fast neutron beam of the biomedical cyclotron in Nice. A thermal peak appears after 5 cm depth in the tissues, delayed after the fast neutron peak at 1.8 cm depth. Thus, a physical overdosage of 10 % may be obtained if 100 ppm of {sup 10}B are assumed in the tissues. Our results using CAL 58 GBM cell line demonstrate a dose modification factor (DMF) of 1.19 when 100 ppm of boric acid are added to the growth medium. Thus for the particles, issued from neutron capture, a biological efficiency at least twice that of fast neutrons can be derived. These results, compared with historical data on fast neutron irradiation of glioblastoma, suggest that a therapeutic window may be obtained for GBM. (author). 26 refs.

  6. Dosimetry and radiobiology at the new RA-3 reactor boron neutron capture therapy (BNCT) facility: application to the treatment of experimental oral cancer.

    Science.gov (United States)

    Pozzi, E; Nigg, D W; Miller, M; Thorp, S I; Heber, E M; Zarza, L; Estryk, G; Monti Hughes, A; Molinari, A J; Garabalino, M; Itoiz, M E; Aromando, R F; Quintana, J; Trivillin, V A; Schwint, A E

    2009-07-01

    The National Atomic Energy Commission of Argentina (CNEA) constructed a novel thermal neutron source for use in boron neutron capture therapy (BNCT) applications at the RA-3 research reactor facility located in Buenos Aires. The aim of the present study was to perform a dosimetric characterization of the facility and undertake radiobiological studies of BNCT in an experimental model of oral cancer in the hamster cheek pouch. The free-field thermal flux was 7.1 x 10(9) n cm(-2)s(-1) and the fast neutron flux was 2.5 x 10(6) n cm(-2)s(-1), indicating a very well-thermalized neutron field with negligible fast neutron dose. For radiobiological studies it was necessary to shield the body of the hamster from the neutron flux while exposing the everted cheek pouch bearing the tumors. To that end we developed a lithium (enriched to 95% in (6)Li) carbonate enclosure. Groups of tumor-bearing hamsters were submitted to BPA-BNCT, GB-10-BNCT, (GB-10+BPA)-BNCT or beam only treatments. Normal (non-cancerized) hamsters were treated similarly to evaluate normal tissue radiotoxicity. The total physical dose delivered to tumor with the BNCT treatments ranged from 6 to 8.5 Gy. Tumor control at 30 days ranged from 73% to 85%, with no normal tissue radiotoxicity. Significant but reversible mucositis in precancerous tissue surrounding tumors was associated to BPA-BNCT. The therapeutic success of different BNCT protocols in treating experimental oral cancer at this novel facility was unequivocally demonstrated. PMID:19380233

  7. Dosimetry and radiobiology at the new RA-3 reactor boron neutron capture therapy (BNCT) facility: Application to the treatment of experimental oral cancer

    International Nuclear Information System (INIS)

    The National Atomic Energy Commission of Argentina (CNEA) constructed a novel thermal neutron source for use in boron neutron capture therapy (BNCT) applications at the RA-3 research reactor facility located in Buenos Aires. The aim of the present study was to perform a dosimetric characterization of the facility and undertake radiobiological studies of BNCT in an experimental model of oral cancer in the hamster cheek pouch. The free-field thermal flux was 7.1x109 n cm-2 s-1 and the fast neutron flux was 2.5x106 n cm-2 s-1, indicating a very well-thermalized neutron field with negligible fast neutron dose. For radiobiological studies it was necessary to shield the body of the hamster from the neutron flux while exposing the everted cheek pouch bearing the tumors. To that end we developed a lithium (enriched to 95% in 6Li) carbonate enclosure. Groups of tumor-bearing hamsters were submitted to BPA-BNCT, GB-10-BNCT, (GB-10+BPA)-BNCT or beam only treatments. Normal (non-cancerized) hamsters were treated similarly to evaluate normal tissue radiotoxicity. The total physical dose delivered to tumor with the BNCT treatments ranged from 6 to 8.5 Gy. Tumor control at 30 days ranged from 73% to 85%, with no normal tissue radiotoxicity. Significant but reversible mucositis in precancerous tissue surrounding tumors was associated to BPA-BNCT. The therapeutic success of different BNCT protocols in treating experimental oral cancer at this novel facility was unequivocally demonstrated.

  8. Dosimetry and radiobiology at the new RA-3 reactor boron neutron capture therapy (BNCT) facility: Application to the treatment of experimental oral cancer

    Energy Technology Data Exchange (ETDEWEB)

    Pozzi, E. [Research and Production Reactors, National Atomic Energy Commission, Ezeiza Atomic Center (Argentina); Department of Radiobiology, National Atomic Energy Commission, Constituyentes Atomic Center (Argentina)], E-mail: epozzi@cnea.gov.ar; Nigg, D.W. [Idaho National Laboratory, Idaho Falls (United States); Miller, M.; Thorp, S.I. [Instrumentation and Control Department, National Atomic Energy Commission, Ezeiza Atomic Center (Argentina); Heber, E.M. [Department of Radiobiology, National Atomic Energy Commission, Constituyentes Atomic Center (Argentina); Zarza, L.; Estryk, G. [Research and Production Reactors, National Atomic Energy Commission, Ezeiza Atomic Center (Argentina); Monti Hughes, A.; Molinari, A.J.; Garabalino, M. [Department of Radiobiology, National Atomic Energy Commission, Constituyentes Atomic Center (Argentina); Itoiz, M.E. [Department of Radiobiology, National Atomic Energy Commission, Constituyentes Atomic Center (Argentina); Department of Oral Pathology, Faculty of Dentistry, University of Buenos Aires (Argentina); Aromando, R.F. [Department of Oral Pathology, Faculty of Dentistry, University of Buenos Aires (Argentina); Quintana, J. [Research and Production Reactors, National Atomic Energy Commission, Ezeiza Atomic Center (Argentina); Trivillin, V.A.; Schwint, A.E. [Department of Radiobiology, National Atomic Energy Commission, Constituyentes Atomic Center (Argentina)

    2009-07-15

    The National Atomic Energy Commission of Argentina (CNEA) constructed a novel thermal neutron source for use in boron neutron capture therapy (BNCT) applications at the RA-3 research reactor facility located in Buenos Aires. The aim of the present study was to perform a dosimetric characterization of the facility and undertake radiobiological studies of BNCT in an experimental model of oral cancer in the hamster cheek pouch. The free-field thermal flux was 7.1x10{sup 9} n cm{sup -2} s{sup -1} and the fast neutron flux was 2.5x10{sup 6} n cm{sup -2} s{sup -1}, indicating a very well-thermalized neutron field with negligible fast neutron dose. For radiobiological studies it was necessary to shield the body of the hamster from the neutron flux while exposing the everted cheek pouch bearing the tumors. To that end we developed a lithium (enriched to 95% in {sup 6}Li) carbonate enclosure. Groups of tumor-bearing hamsters were submitted to BPA-BNCT, GB-10-BNCT, (GB-10+BPA)-BNCT or beam only treatments. Normal (non-cancerized) hamsters were treated similarly to evaluate normal tissue radiotoxicity. The total physical dose delivered to tumor with the BNCT treatments ranged from 6 to 8.5 Gy. Tumor control at 30 days ranged from 73% to 85%, with no normal tissue radiotoxicity. Significant but reversible mucositis in precancerous tissue surrounding tumors was associated to BPA-BNCT. The therapeutic success of different BNCT protocols in treating experimental oral cancer at this novel facility was unequivocally demonstrated.

  9. The physics experimental study for in-hospital neutron irradiator

    International Nuclear Information System (INIS)

    MNSRs (Miniature Neutron Source Reactor) are low power research reactors designed and manufactured by China Institute of Atomic Energy (CIAE). MNSRs are mainly used for NAA, training and teaching, testing of nuclear instrumentation. The first MNSR, the prototype MNSR, was put into operation in 1984, later, eight other MNSRs had been built both at home and abroad. For MNSRs, highly enriched uranium (90%) is used as the fuel material. The In-Hospital Neutron Irradiator (IHNI) is designed for Boron Neutron Capture Therapy (BNCT) based on Miniature Neutron Source Reactor(MNSR). On both sides of the reactor core, there are two neutron beams, one is thermal neutron beam, and the other opposite to the thermal beam, is epithermal neutron beam. A small thermal neutron beam is specially designed for the measurement of blood boron concentration by the prompt gamma neutron activation analysis (PGNAA). In this paper, the experimental results of critical mass worth of the top Be reflectors worth of the control rod, neutron flux distribution and other components worth were measured, the experiment was done on the Zero Power Experiment equipment of MNSR. (author)

  10. In vivo BNCT in experimental and spontaneous tumors at RA-1 reactor

    International Nuclear Information System (INIS)

    Within the search for new applications of Boron Neutron Capture Therapy (BNCT) and the basic research oriented towards the study of BNCT radiobiology to optimize its therapeutic gain, we previously proposed and validated the hamster cheek pouch oral cancer model and showed, for the first time, the success of BNCT to treat oral cancer in an experimental model. The staff of the Ra-1 Reactor (Constituyentes Atomic Center) adapted the thermal beam and physical set-up to perform in vivo BNCT of superficial tumors in small animals. We preformed a preliminary characterization of the thermal beam, performed beam only irradiation of normal and tumor bearing hamsters and in vivo BNCT of experimental oral squamous cell carcinomas in hamsters mediated by boron phenylalanine (BPA) and GB-10 (Na210B10H10). Having demonstrated the absence of radio toxic effects in healthy tissue and a therapeutic effect of in vivo BNCT in hamster cheek pouch tumors employing the Ra-1 thermal beam, we performed a feasibility study of the treatment by BNCT of 3 terminal cases of spontaneous head and neck squamous cell carcinoma in cats following the corresponding biodistribution studies. This was the first treatment of spontaneous tumors by BNCT in our country and the first treatment by BNCT in cats worldwide. This preclinical study in terminal cases showed significant tumor control by BNCT with no damage to normal tissue. (author)

  11. Feasibility of boron neutron capture therapy (BNCT) for malignant pleural mesothelioma from a viewpoint of dose distribution analysis

    International Nuclear Information System (INIS)

    Purpose: To investigate the feasibility of boron neutron capture therapy (BNCT) for malignant pleural mesothelioma (MPM) from a viewpoint of dose distribution analysis using Simulation Environment for Radiotherapy Applications (SERA), a currently available BNCT treatment planning system. Methods and Materials: The BNCT treatment plans were constructed for 3 patients with MPM using the SERA system, with 2 opposed anterior-posterior beams. The 1B concentrations in the tumor and normal lung in this study were assumed to be 84 and 24 ppm, respectively, and were derived from data observed in clinical trials. The maximum, mean, and minimum doses to the tumors and the normal lung were assessed for each plan. The doses delivered to 5% and 95% of the tumor volume, D05 and D95, were adopted as the representative dose for the maximum and minimum dose, respectively. Results: When the D05 to the normal ipsilateral lung was 5 Gy-Eq, the D95 and mean doses delivered to the normal lung were 2.2-3.6 and 3.5-4.2 Gy-Eq, respectively. The mean doses delivered to the tumors were 22.4-27.2 Gy-Eq. The D05 and D95 doses to the tumors were 9.6-15.0 and 31.5-39.5 Gy-Eq, respectively. Conclusions: From a viewpoint of the dose-distribution analysis, BNCT has the possibility to be a promising treatment for MPM patients who are inoperable because of age and other medical illnesses

  12. Histopathological changes of testes and eyes by neutron irradiation with boron compounds in mice.

    Science.gov (United States)

    Kim, Yeon-Joo; Yoon, Won-Ki; Ryu, Si-Yun; Chun, Ki-Jung; Son, Hwa-Young; Cho, Sung-Whan

    2006-03-01

    This study was performed to investigate the biological effects of boron neutron capture therapy (BNCT) on the testes and eyes in mice using HANARO Nuclear Reactor, Korea Atomic Energy Research Institute. BNCT relies on the high capacity of 10B in capturing thermal neutrons. Sodium borocaptate (BSH, 75 ppm, iv) and boronophenylalanine (BPA, 750 ppm, ip) have been used as the boron delivery agents. Mice were irradiated with neutron (flux: 1.036739E +09, Fluence 9.600200E+12) by lying flat pose for 30 (10 Gy) or 100 min (33 Gy) with or without boron carrier treatment. In 45 days of irradiation, histopathological changes of the testes and eyes were examined. Thirty-three Gy neutron irradiation for 100 min induced testicular atrophy in which some of seminiferous tubules showed complete depletion of spermatogenic germ cells. Lens epithelial cells and lens fiber were swollen and showed granular changes in an exposure time dependent manner. However, boron carrier treatment had no significant effect on the lesions. These results suggest that the examination of histopathological changes of lens and testis can be used as "biological dosimeters" for gauging radiation responses and the HANARO Nuclear Reactor has sufficient capacities for the BNCT. PMID:16434844

  13. Considerations for boron neutron capture therapy studies; Consideracoes sobre o estudo da BNCT (terapia de captura neutronica por boro)

    Energy Technology Data Exchange (ETDEWEB)

    Faria Gaspar, P. de

    1994-12-31

    Radiotherapy is indispensable as a mean to eradicate deeply or infiltrating tumor tissue that can not be removed surgically. Therefore, it is not selective and may also kill the surrounding health tissue. The principle of BNCT (Boron Neutron Capture Therapy) consist in targeting a tumor selectively with a boron-10 compound. This nuclide has a large capture cross section for thermal neutrons and the nuclear reaction and the delivered energy in locus will selective the tumor. Since its initial proposal in 1963 BNCT has made much progress, however it is not used in a routine treatment. In this work it was approached some complex procedures, as the obtention of selective boron compounds, the adequate set up of neutron beams, the biodistribution, the in vivo and in vitro studies, and also human patients treatments. This work provide fundamentals about BNCT to professional of different areas of knowledge since it comprises multidisciplinary study. It includes appendixes for the ones not related to the field for a better comprehension of the many aspects involved. It is also presented a glossary containing technical and basic aspects involved. It is also presented a glossary containing technical and basic terms referred in the work. (author). 174 refs, 1 fig, 12 apps.

  14. Sodium borocaptate (BSH) for Boron Neutron Capture Therapy (BNCT) in the hamster cheek pouch oral cancer model: boron biodistribution at 9 post administration time-points

    International Nuclear Information System (INIS)

    The therapeutic success of Boron Neutron Capture Therapy (BNCT) depends centrally on boron concentration in tumor and healthy tissue. We previously demonstrated the therapeutic efficacy of boronophenylalanine (BPA) and sodium decahydrodecaborate (GB-10) as boron carriers for BNCT in the hamster cheek pouch oral cancer model. Given the clinical relevance of sodium mercaptoundecahydro-closo-dodecaborate (BSH) as a boron carrier, the aim of the present study was to expand the ongoing BSH biodistribution studies in the hamster cheek pouch oral cancer model. In particular, we studied 3 additional post-administration time-points and increased the sample size corresponding to the time-points evaluated previously, to select more accurately the post-administration time at which neutron irradiation would potentially confer the greatest therapeutic advantage. BSH was dissolved in saline solution in anaerobic conditions to avoid the formation of the dimer BSSB and its oxides which are toxic. The solution was injected intravenously at a dose of 50 mg 10 B/kg (88 mg BSH / kg). Different groups of animals were killed humanely at 7, 8, and 10 h after administration of BSH. The sample size corresponding to the time-points 3, 4, 6, 9 and 12 h was increased. Samples of blood, tumor, precancerous tissue, normal pouch tissue, cheek mucosa, parotid gland, palate, skin, tongue, spinal cord marrow, brain, liver, kidney, spleen and lung were processed for boron measurement by Optic Emission Spectroscopy (ICP-OES). Boron concentration in tumor peaked to 24-34 ppm, 3-10 h post-administration of BSH, with a spread in values that resembled that previously reported in other experimental models and human subjects. The boron concentration ratios tumor/normal pouch tissue and tumor/blood ranged from 1.3 to 1.8. No selective tumor uptake was observed at any of the time points evaluated. The times post-administration of BSH that would be therapeutically most useful would be 5, 7 and 9 h. The

  15. Are high energy proton beams ideal for AB‐BNCT? A brief discussion from the viewpoint of fast neutron contamination control

    International Nuclear Information System (INIS)

    High energy proton beam (>8 MeV) is favorable for producing neutrons with high yield. However, the produced neutrons are of high energies. These high energy neutrons can cause severe fast neutron contamination and degrade the BNCT treatment quality if they are not appropriately moderated. Hence, this study aims to briefly discuss the issue, from the viewpoint of fast neutron contamination control, whether high energy proton beam is ideal for AB-BNCT or not. In this study, D2O, PbF4, CaF2, and Fluental™ were used standalone as moderator materials to slow down 1-, 6-, and 10-MeV parallelly incident neutrons. From the calculated results, we concluded that neutrons produced by high energy proton beam could not be easily moderated by a single moderator to an acceptable contamination level and still with reasonable epithermal neutron beam intensity. Hence, much more complicated and sophisticated designs of beam shaping assembly have to be developed when using high energy proton beams. - Highlights: • The fast neutron contamination profiles of 3 different moderator materials were discussed. • D2O, PbF4 and Fluental™ were tested as standalone moderators. • Standalone moderator cannot effectively suppress fast neutrons higher than 1 MeV. • AB-BNCT by high energy proton beam suffers serious fast neutron contamination. • The use of high energy protons (>8 MeV) for AB-BNCT should be carefully evaluated

  16. Intercalibration of physical neutron dosimetry for the RA-3 and MURR thermal neutron sources for BNCT small-animal research

    International Nuclear Information System (INIS)

    New thermal neutron irradiation facilities to perform cell and small-animal irradiations for Boron Neutron Capture Therapy research have been installed at the Missouri University Research Reactor and at the RA-3 research reactor facility in Buenos Aires, Argentina. Recognizing the importance of accurate and reproducible physical beam dosimetry as an essential tool for combination and intercomparisons of preclinical and clinical results from the different facilities, we have conducted an experimental intercalibration of the neutronic performance of the RA-3 and MURR thermal neutron sources.

  17. Intercalibration of physical neutron dosimetry for the RA-3 and MURR thermal neutron sources for BNCT small-animal research.

    Science.gov (United States)

    Pozzi, Emiliano C C; Thorp, Silvia; Brockman, John; Miller, Marcelo; Nigg, David W; Hawthorne, M Frederick

    2011-12-01

    New thermal neutron irradiation facilities to perform cell and small-animal irradiations for Boron Neutron Capture Therapy research have been installed at the Missouri University Research Reactor and at the RA-3 research reactor facility in Buenos Aires, Argentina. Recognizing the importance of accurate and reproducible physical beam dosimetry as an essential tool for combination and intercomparisons of preclinical and clinical results from the different facilities, we have conducted an experimental intercalibration of the neutronic performance of the RA-3 and MURR thermal neutron sources. PMID:21330143

  18. Physical and tumor biological aspects and calculation model of dosage in boron neutron capture therapy (BNCT)

    Energy Technology Data Exchange (ETDEWEB)

    Rassow, J.; Poeller, F.; Meissner, P. (Essen Univ. (Gesamthochschule) (Germany). Abt. fuer Medizinische Strahlenphysik); Steinberg, F. (Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Medizinische Strahlenbiologie)

    1993-01-01

    Fundamentally different aspects apply to dosage in boron neutron capture therapy (BNCT) compared to that in the case of normal radiotherapy with photons, electrons or heavy particles such as neutrons. The reason is that the latter only requires a knowledge of the stochastic distribution of the absorbed dose within cells, radiation quality and atomic composition of tissue in the regions of interest, whereas for the former the absolute concentration and microscopic distribution of [sup 10]B atoms in inter- and intracellular spaces of tumor and healthy cells is additionally of equal importance. The effects of radiation without [sup 10]B must always be superimposed on those of heavy particles resulting from neutron capture reactions on [sup 10]B atoms. Complex geometrical calculaations are necessary with respect to ranges of the heavy particles smaller than a cell diameter. Apart from the direct effects of radiation without [sup 10]B, the dosage therefore depends on thermal neutron fluence, [sup 10]B concentration, its extreme inhomogeneous macroscopic distribution in the tumor tissue, the cellular localization of the [sup 10]B atoms in the large intercellular space, the cell membrane, within cytoplasm or the cell nucleus, the geometrical probability of hitting the cell nucleus, and that such a hit finally results in a cell killing, and a Poisson statistical enhancement factor, which describes the dose-effect relation for cell survival. The calculations necessary are demonstrated in the case of a normal and a tumor cell type, each with representative cell diameter and nucleus size. It is evident that the microscopic distribution of [sup 10]B atoms is one of the most critical parameters which is still insufficiently known. (orig.).

  19. Design of a BNCT facility at HANARO

    International Nuclear Information System (INIS)

    Based on the feasibility study of the BNCT at HANARO, it was confirmed that only thermal BNCT is possible at the IR beam tube if appropriate filtering system be installed. Medical doctors in Korea Cancer Center Hospital agreed that the thermal BNCT facility would be worthwhile for the BNCT technology development in Korea as well as superficial cancer treatment. For the thermal BNCT to be effective, the thermal neutron flux should be high enough for patient treatment during relatively short time and also the fast neutron and gamma-ray fluxes should be as low as possible to avoid high dose on the patient during treatment. In this point of view, the following design requirements are set up; 1) thermal neutron flux at the irradiation position should be higher than 2 X 109 n/cm2 . sec, 2) ration of the fast neutrons and gamma-rays to the thermal neutrons should be minimized, and 3) patient treatment should be possible during reactor operation. To minimize the fast neutrons and gamma-rays with the required thermal neutrons at the irradiation position, a radiation filter consisting of single crystals of silicon and bismuth at liquid nitrogen temperature is design d. For the shielding purpose around the irradiation position, polyethylene, lead, LiF, etc., are appropriately arranged around the radiation filter. A water shutter in front of the radiation filter is adopted so as to avoid interrupt to the reactor operation. While the shutter is filled in water during on power, the radiation level in the irradiation room is sufficiently low for the preparation work for patient irradiation including temporary surgery. At present, detail design of the radiation filter is ongoing. cooling capabilities of the filter will be tested through a mockup experiment. Dose rate distributions around the radiation filter are under analysis for the configuration of the irradiation room. A prompt gamma-ray activation analysis system for the analyses of boron content in the biological samples, is

  20. First clinical results from the EORTC phase I Trial ''postoperative treatment of glioblastoma with BNCT at the Petten irradiation facility''

    International Nuclear Information System (INIS)

    Based on the pre-clinical work of the European Collaboration on Boron Neutron Capture Therapy a study protocol was prepared in 1995 to initiate Boron Neutron Capture Therapy (BNCT) in patients at the High Flux Reactor (HFR) in Petten. Bio-distribution and pharmacokinetics data of the boron drug Na2B12H11SH (BSH) as well as the radiobiological effects of BNCT with BSH in healthy brain tissue of dogs were considered in designing the strategy for this clinical Phase I trial. The primary goal of the radiation dose escalation study is the investigation of possible adverse events due to BNCT; i.e. to establish the dose limiting toxicity and the maximal tolerated dose. The treatment is delivered in 4 fractions at a defined average boron concentration in blood. Cohorts of 10 patients are treated per dose group. The starting dose was set at 80% of the dose at which neurological symptoms occurred in preclinical dog experiments following a single fraction. After an observation period of at least 6 months, the dose is increased by 10% for the next cohort if less then three severe side effects related to the treatment occurred. The results of the first cohort are presented here. The evaluated dose level can be considered safe. (author)

  1. Summary of recent BNCT Polish programme and future plans.

    Science.gov (United States)

    Gryziński, M A; Maciak, M; Wielgosz, M

    2015-12-01

    In this work we present Polish achievements on the ground of BNCT research. Starting from preliminary built therapeutic stand at MARIA reactor going through designing of unique detectors for in-phantom and in-beam measurements for mixed radiation fields and finally coming to boron carriers synthesizing and examination in cellular and animal models. Now it is planned to restart research on boron compounds in specially designed BIMA line, to set up epithermal neutron irradiation facility for BNCT research and education and to improve recombination detectors for neutron beams characterisation. PMID:26293009

  2. A virtual model of the patient's head for BNCT

    International Nuclear Information System (INIS)

    The aim of the present work was creating a virtual phantom of a human head for BNCT, as a part of the BNCT programme project. This model is an amplification of the simple model described in earlier publications. It takes into account the major head organs as well as the scalp and skull. The chemical composition of all tissues was modelled according to the recommendations of the ICRP. The organs were parameterized using mathematical formulas based on the human head magnetic resonance images. The model was used for calculating the thermal neutron flux and the injuring (fast neutron, nitrogen and gamma) dose components for the head irradiated using the therapeutic neutron beam, whose parameters were obtained as the result of the modelling of the filter/moderator system for the BNCT therapeutic beam from the MARIA reactor. (authors)

  3. Spectromicroscopy of boron for the optimization of boron neutron capture therapy (BNCT) for cancer

    International Nuclear Information System (INIS)

    We used synchrotron spectromicroscopy to study the microscopic distribution of boron in rat brain tumour and healthy tissue in the field of boron neutron capture therapy (BNCT). The success of this experimental cancer therapy depends on the preferential uptake of 10B in tumour cells after injection of a boron compound (in our case B12H11SH, or BSH). With the Mephisto (microscope a emission de photoelectrons par illumination synchrotronique de type onduleur) spectromicroscope, high-magnification imaging and chemical analysis was performed on brain tissue sections from a rat carrying an implanted brain tumour and the results were compared with inductively coupled plasma-atomic emission spectroscopy (ICP-AES) detection of boron in bulk tissue. Boron was found to have been taken up more favourably by regions of tumour rather than healthy tissue, but the resulting boron distribution in the tumour was inhomogeneous. The results demonstrate that Mephisto can perform microchemical analysis of tissue sections, detect and localize the presence of boron with submicron spatial resolution. The application of this technique to boron in brain tissue can therefore be used to evaluate the current efforts to optimize BNC therapy. (author)

  4. Boron neutron capture therapy (BNCT) using fast neutrons: Effects in two human tumor cell lines

    International Nuclear Information System (INIS)

    The results demonstrate that the effect of fast neutrons on cell survival in cell culture can be enhanced by boron neutron capture reaction. Even with lower enhancement ratios, the concept of NCT assisted fast neutron therapy may successfully be applied for tumor treatment with the Essen cyclotron. (orig.)

  5. In-phantom characterisation studies at the Birmingham Accelerator-Generated epIthermal Neutron Source (BAGINS) BNCT facility.

    Science.gov (United States)

    Culbertson, Christopher N; Green, Stuart; Mason, Anna J; Picton, David; Baugh, Gareth; Hugtenburg, Richard P; Yin, Zaizhe; Scott, Malcolm C; Nelson, John M

    2004-11-01

    A broad experimental campaign to validate the final epithermal neutron beam design for the BNCT facility constructed at the University of Birmingham concluded in November 2003. The final moderator and facility designs are overviewed briefly, followed by a summary of the dosimetric methods and presentation of a small subset of the results from this campaign. The dual ionisation chamber technique was used together with foil activation to quantify the fast neutron, photon, and thermal neutron beam dose components in a large rectangular phantom exposed to the beam with a 12 cm diameter beam delimiter in place. After application of a normalisation factor, dose measurements agree with in-phantom MCNP4C predictions within 10% for the photon dose, within 10% for thermal neutron dose, and within 25% for the proton recoil dose along the main beam axis. PMID:15308136

  6. Neutron irradiation of seeds 2

    International Nuclear Information System (INIS)

    The irradiation of seeds with the fast neutron of research reactors has been hampered by difficulties in accurately measuring dose and in obtaining repeatable and comparable results. Co-ordinated research under an international program organized by the FAO and IAEA has already resulted in significant improvements in methods of exposing seeds in research reactors and in obtaining accurate dosimetry. This has been accomplished by the development of a standard reactor facility for the neutron irradiation of seeds and standard methods for determining fast-neutron dose and the biological response after irradiation. In this program various divisions of the IAEA and the Joint FAO/IAEA Division co-operate with a number of research institutes and reactor centres throughout the world. Results of the preliminary experiments were reported in Technical Reports Series No. 76, ''Neutron Irradiation of Seeds''. This volume contains the proceedings of a meeting of co-operators in the FAO/IAEA Neutron Seed Irradiation Program and other active scientists in this field. The meeting was held in Vienna from 11 to 15 December 1967. Refs, figs and tabs

  7. TL detectors in BNCT dosimetry

    International Nuclear Information System (INIS)

    The main detectors for characterising and controlling of BNCT beams are activation foils and paired ionisation chambers. Thermoluminescent (TL) dosimeters are also of interest because of their following advantages: i) small physical size, ii) no need for high voltage or cables, i.e. stand alone character, and iii) suitability for large scale measurements; with TL dosimeters it is possible to measure depth dose curves and profiles at the same time, with one irradiation. Also, TL dosimeters may be possible detectors for in vivo use. At the Finnish BNCT facility, a TL detector MTS-Ns of TLD Niewiadomski and Co. (Krakow, Poland) with an ultrathin active LiF:Mg,Ti layer for small self-shielding of thermal neutrons was selected for use as a neutron sensitive dosimeter. A TL detector MCP-7s (7LiF:Mg,Cu,P) of the same manufacturer was used for gamma detection because of its high sensitivity to gamma radiation compared to that to high LET radiation. The gamma dose and neutron fluence distributions have been measured in PMMA, water and brain substitute liquid phantoms at the BNCT beam. Gamma dose and neutron fluence profiles measured with TL detectors correlate with those calculated using DORT (Two Dimensional Discrete Ordinates Transport Code) and measured with ionisation chambers. NITS-Ns TL detectors were found to measure accurately (8%, 1 S.D.) the relative neutron fluence, and therefore to be a useful addition to the activation foils in BNCT neutron dosimetry. Due to the high uncertainty of the thermal neutron sensitivity of the MCP-7s TL detectors, the absorbed gamma doses can be measured with MCP-7s detectors within 20% in the mixed neutron-gamma field of BNCT. The treatments of glioma patients at the Finnish BNCT facility will start in the spring 1999. The doses to the target volume and sensitive organs, i.e. brain, will be calculated individually in the dose planning. Since it is also necessary to monitor the absorbed doses to the head and to the body, in vivo

  8. Neutron scattering on neutron irradiated steel

    International Nuclear Information System (INIS)

    Three pressure vessel steel systems (two base material and one weld material) with a 50% irradiation induced hardness enhancement were investigated by small angle neutron scattering. All three steel systems were irradiated in the light water moderated research reactor FRJ-1 at a temperature of 1500C. The strongest scattering effect was found for steel A; a pressure vessel containment steel ASTM a 533 B. This system was irradiated with a fluence of 7 1019 n/cm2 (E > 1 MeV). The annealing behaviour was then investigated after isochronal anneals of 300, 350, 400 and 4500C. Viker's hardness measurements were made parallel to the neutron scattering experiments. The hardness enhancement of 50% decreased after the first anneal to 30% and after the second to 18%. The neutron scattering patterns show a decrease in the number of very small voids having a Guinier radius less than 5 A. These voids have annealed, or coagulated into larger voids (Rg = 20-25 A) with a density of n = 1015 cm-3. After the third anneal at 4000C, the scattering patterns became, within statistical errors, identical to the scattering pattern of the unirradiated specimen; but a hardness enhancement of 13% was measured. (orig./WBU)

  9. The alanine detector in BNCT dosimetry: Dose response in thermal and epithermal neutron fields

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, T., E-mail: schmito@uni-mainz.de [Institute for nuclear chemistry, Johannes Gutenberg-University, Mainz D-55128 (Germany); Bassler, N. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, Aarhus C, Aarhus 8000 (Denmark); Blaickner, M. [AIT Austrian Institute of Technology GmbH, Vienna A-1220 (Austria); Ziegner, M. [AIT Austrian Institute of Technology GmbH, Vienna A-1220, Austria and TU Wien, Vienna University of Technology, Vienna A-1020 (Austria); Hsiao, M. C. [Insitute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Liu, Y. H. [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Koivunoro, H. [Department of Physics, University of Helsinki, POB 64, FI-00014, Finland and HUS Medical Imaging Center, Helsinki University Central Hospital, FI-00029 HUS (Finland); Auterinen, I.; Serén, T.; Kotiluoto, P. [VTT Technical Research Centre of Finland, Espoo (Finland); Palmans, H. [National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington TW11 0LW, United Kingdom and Medical Physics Group, EBG MedAustron GmbH, Wiener Neustadt A-2700 (Austria); Sharpe, P. [National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington TW11 0LW (United Kingdom); Langguth, P. [Department of Pharmacy and Toxicology, University of Mainz, Mainz D-55128 (Germany); Hampel, G. [Institut für Kernchemie, Johannes Gutenberg-Universität, Mainz D-55128 (Germany)

    2015-01-15

    Purpose: The response of alanine solid state dosimeters to ionizing radiation strongly depends on particle type and energy. Due to nuclear interactions, neutron fields usually also consist of secondary particles such as photons and protons of diverse energies. Various experiments have been carried out in three different neutron beams to explore the alanine dose response behavior and to validate model predictions. Additionally, application in medical neutron fields for boron neutron capture therapy is discussed. Methods: Alanine detectors have been irradiated in the thermal neutron field of the research reactor TRIGA Mainz, Germany, in five experimental conditions, generating different secondary particle spectra. Further irradiations have been made in the epithermal neutron beams at the research reactors FiR 1 in Helsinki, Finland, and Tsing Hua open pool reactor in HsinChu, Taiwan ROC. Readout has been performed with electron spin resonance spectrometry with reference to an absorbed dose standard in a {sup 60}Co gamma ray beam. Absorbed doses and dose components have been calculated using the Monte Carlo codes FLUKA and MCNP. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using the Hansen and Olsen alanine response model. Results: The measured dose response of the alanine detector in the different experiments has been evaluated and compared to model predictions. Therefore, a relative effectiveness has been calculated for each dose component, accounting for its dependence on particle type and energy. Agreement within 5% between model and measurement has been achieved for most irradiated detectors. Significant differences have been observed in response behavior between thermal and epithermal neutron fields, especially regarding dose composition and depth dose curves. The calculated dose components could be verified with the experimental results in the different primary and secondary particle fields. Conclusions: The

  10. Clinical practice in BNCT to the brain

    International Nuclear Information System (INIS)

    Our concept of Boron Neutron Capture Therapy (BNCT) is to selectively destroy tumour cells using the high LET particles yielded from the 10B(n,α)7Li reactions. The effort of clinical investigators has concentrated on how to escalate the radiation dose at the target point. BNCT in Japan combines thermal neutrons and BSH (Na2B12H11SH). The radiation dose is determined by the neutron fluence at the target point and the boron concentration in the tumour tissue. According to the recent analysis, the ratio of boron concentration (BSH) in tumour tissue and blood is nearly stable at around 1.2 to 1.69. Escalation of the radiation dose was carried out by means of improving the penetration of the thermal neutron beam. Since 1968, 175 patients with glioblastoma (n=83), anaplastic astrocytoma (n=44), low grade astrocytoma (n=16) or other types of tumour (n=32) were treated by BNCT at 5 reactors (HTR n=13, JRR-3 n=1, MulTR n=98, KUR n=30, JRR-2 n=33). The retrospective analysis revealed that the important factors related to the clinical results and QOL of the patients were minimum tumour volume radiation dose, more than 18Gy of physical dose and maximum vascular radiation dose (less than 15Gy) in the normal cortex. We have planned several trials to escalate the target radiation dose. One trial makes use of a cavity in the cortex following debulking surgery of the tumour tissue to improve neutron penetration. The other trial is introduction of epithermal neutron. KUR and JRR-4 were reconstructed and developed to be able to irradiate using epithermal neutrons. The new combination of surgical procedure and irradiation using epithermal neutrons should remarkably improve the target volume dose compared to the radiation dose treated by thermal neutrons. (author)

  11. Histological and biochemical analysis of DNA damage after BNCT in rat model

    International Nuclear Information System (INIS)

    To understand the mechanism of tumor cell death induced by boron neutron capture therapy (BNCT) and to optimize BNCT condition, we used rat tumor graft models and histological and biochemical analyses were carried out focusing on DNA damage response. Rat lymphosarcoma cells were grafted subcutaneously into male Wister rats. The rats with developed tumors were then treated with neutron beam irradiation 45 min after injection of 330 mg/kg bodyweight boronophenylalanine (10BPA) (+BPA) or saline control (–BPA). BNCT was carried out in the National Nuclear Center of the Republic of Kazakhstan (neutron flux: 1×109 nvt/s, fluence: 6×1011 nvt) with the presence of background γ-irradiation of 33 Gy. 6 and 20 h after BNCT treatment, tumors were resected, fixed and subjected to immunohistochemistry and biochemical analyses. Immunostaining of nuclei showed that double strand break (DSB) marker gamma H2AX staining was high in 20 h/+BPA sample but not in 20 h/–BPA samples. Poly(ADP-ribose), DSB and single strand break markers of DNA, also demonstrated this tendency. These two markers were observed at low levels in unirradiated tissues or 6 h after BNCT either under −BPA and +BPA conditions. HMGB1 level increased in 6 h/+BPA but not in 6 h/−BPA or 20 h/+BPA samples. The persistent staining of γH2AX and poly(ADP-ribose) in +BPA group suggests accumulated DSB damage after BNCT. The early HMGB1 upregulation and γH2AX and poly(ADP-ribose) observed later might be the markers for monitoring the DNA damage induced by BNCT. - Highlights: • We used rat tumor graft models and DNA damage response in BNCT was analyzed. • HMGB1 upregulation was suggested to be an early marker for BNCT. • The persistent presence of γH2AX and PAR in the nuclei might serve as late markers

  12. Determining and reporting the doses in the treatments of glioma patients in the epithermal neutron beam at the Finnish BNCT facility (FIR 1)

    International Nuclear Information System (INIS)

    The clinical trials of glioma patients at the Finnish boron neutron capture therapy (BNCT) facility (FiR 1) started in May 1999. The doses of the patient in tumour, target volume and sensitive tissues are calculated individually. The calculated doses are calibrated to the reference monitor units according to the ratio of the independently measured and calculated 197Au(n,g) reactions rates at the depth of 20 mm on the central axis of a cylindrical PMMA phantom chosen as the reference geometry. Absorbed doses to the head and body are monitored individually using in vivo dosimeters. In BNCT the total dose is the weighted sum of the absorbed doses originating from the neutron and gamma interactions in tissues. The material compositions of the head model for the neutron-gamma transport calculation and kerma factors are based on the ICRU report 46. The doses in the clinical research of BNCT should be reported in such a way that the doses are comparable, traceable and can be recalculated, if underlying information, like weighting factors for dose components, are replaced by new ones. The minimum, maximum, average and reference doses are reported for the tumour, target and normal brain. In addition to the total weighted doses the dose components (boron, gamma, nitrogen and fast neutron dose), weighting factors and estimated boron concentration in these tissues are reported. There are no international recommendations available for BNCT dose calculation or reporting. Therefore the BNCT doses reported in the literature may not be comparable and a careless use of values can lead to over- or underdosing. There is an obvious need for standardisation in the medical application of BNCT. In this paper the methods of dose calculation and reporting of the glioma patients at FiR 1 are described. (author)

  13. Simple computational modeling for human extracorporeal irradiation using the BNCT facility of the RA-3 Reactor

    International Nuclear Information System (INIS)

    We present a simple computational model of the reactor RA-3 developed using Monte Carlo transport code MCNP. The model parameters are adjusted in order to reproduce experimental measured points in air and the source validation is performed in an acrylic phantom. Performance analysis is carried out using computational models of animal extracorporeal irradiation in liver and lung. Analysis is also performed inside a neutron shielded receptacle use for the irradiation of rats with a model of hepatic metastases.The computational model reproduces the experimental behavior in all the analyzed cases with a maximum difference of 10 percent. (author)

  14. P13.09ADVANCES IN CLINICAL APPLICATION OF BORON NEUTRON CAPTURE THERAPY (BNCT) IN GLIOBLASTOMA

    Science.gov (United States)

    Detta, A.; Cruickshank, G.C.; Green, S.; Lockyer, N.P.; Ngoga, D.; Ghani, Z.; Phoenix, B.

    2014-01-01

    BNCT is a biologically targeted form of enhanced cellular radiotherapy where preferential accumulation of boron in the cancerous as opposed to adjacent normal cells is able to interact with incident neutrons to cause irreversible alpha particle DNA damage. The key to the implementation of this potentially powerful and selective therapy is the delivery of at least 30ppm 10B within the tumour tissue while minimising superfluous 10B in healthy tissue. It is thus an elegant technique for treating infiltrating tumours such as diffuse gliomas. In order to assess its clinical potential we carried out a pharmacokinetic study in glioblastoma patients where we sought to determine the optimal route of delivering a new formulation of the boronated drug (p-boronophenylalanine, BPA), its pharmacokinetic behaviour, toxicity profile, and cellular uptake. Using a number of analytical techniques, including inductively-coupled plasma mass spectrometry, secondary ion mass spectrometry (SIMS) and immunohistochemistry (IHC), boron was measured at various times in blood, urine, cerebrospinal fluid, extracellular fluid (ECF), and tumour-related solid tissue spanning 0.5 h pre- and up to 48 h post-BPA infusion in newly-diagnosed patients (n = 10). Blood was sampled through a central catheter whilst the ECF was sampled by parenchymal microdialysis catheters, placed remotely from the tumour site. Urine was collected over the same time period. Tumour and brain-around tumour (BAT) tissue was sampled stereotactically at 2.5 h and 3.5 h post-infusion. IHC expression levels of the BPA transporter molecule, L-amino acid transporter 1 (LAT-1), were recorded as % LAT-1 positive cells, and cellular boron levels were estimated as spatially resolved pixels in normalised-to-C+ isotopic SIMS images of the biopsies. There were no toxicity-related issues with this new formulation of BPA given at 375 mg/kg as a 2 h intravenous or intracarotid infusion with or without pre-infusion mannitol-induced BBB

  15. Materials irradiation research in neutron science

    Energy Technology Data Exchange (ETDEWEB)

    Noda, Kenji; Oyama, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-11-01

    Materials irradiation researches are planned in Neutron Science Research Program. A materials irradiation facility has been conceived as one of facilities in the concept of Neutron Science Research Center at JAERI. The neutron irradiation field of the facility is characterized by high flux of spallation neutrons with very wide energy range up to several hundred MeV, good accessibility to the irradiation field, good controllability of irradiation conditions, etc. Extensive use of such a materials irradiation facility is expected for fundamental materials irradiation researches and R and D of nuclear energy systems such as accelerator-driven incineration plant for long-lifetime nuclear waste. In this paper, outline concept of the materials irradiation facility, characteristics of the irradiation field, preliminary technical evaluation of target to generate spallation neutrons, and materials researches expected for Neutron Science Research program are described. (author)

  16. The Boron Neutron Capture Therapy (BNCT) Project at the TRIGA Reactor in Mainz, Germany

    DEFF Research Database (Denmark)

    Hampel, G.; Grunewald, C.; Schütz, C.;

    2011-01-01

    years ago, where patients with liver metastases were treated successfully by combining BNCT with auto-transplantation of the organ. Here, in Mainz, a preclinical trial has been started on patients suffering from liver metastases of colorectal carcinoma. In vitro experiments and the first animal tests...... have also been initiated to investigate radiobiological effects of radiation generated during BNCT. For both experiments and treatment, a reliable dosimetry system is necessary. From work elsewhere, the use of alanine detectors appear to be an appropriate dosimetry technique....

  17. BNCT. Computational Analysis; BNCT. Analisis computacional

    Energy Technology Data Exchange (ETDEWEB)

    Caro, R.

    2004-07-01

    The BNCT (Boron Neutron Capture Therapy) is a new oncologic radiotherapy technique in the process of research which consists of injecting a non-poisonous pharmacovector into an ill patient in such a way that the tumor receives isotope boron-10, so that the tumoral area can later be bombarded with a beam of neutrons, many of which are captured the isotope in question. (Author)

  18. Neutron irradiation of bacteriophage λ

    International Nuclear Information System (INIS)

    Double strand breaks (DSB) are the most dangerous lesions in DNA caused by irradiation, but many other lesions, usually called mutations, have not been clearly identified. These lesions, like DSB, can be the source of serious chromosomal damages and finally - cell death. Growing interest in heavy particles for radiotherapy and radioprotection encourages the search of the molecular basis of their action. In this respect, we chose bacteriophage λ1390 as the model system for the study of consequences of neutron irradiation. This derivative of λ phage possesses an unique ability to reversibly reorganize their genome in response to various selective pressures. The phages were irradiated with 13 Gy of mixed neutrons (7.5 Gy from fast and 5.6 Gy from thermal neutrons) and phages genomes were tested to DSB and mutations. Additionally, the stability of λ capsid proteins were tested. After all tests, we can conclude that, under our conditions, low flux of neutrons does not induce neither DNA strand break or DNA mutation nor the stability of λ capsid proteins. (author)

  19. Depth-dose evaluation for lung and pancreas cancer treatment by BNCT using an epithermal neutron beam

    International Nuclear Information System (INIS)

    The depth-dose distributions were evaluated for possible treatment of both lung and pancreas cancers using an epithermal neutron beam. The MCNP calculations showed that physical dose in tumors were 6 and 7 Gy/h, respectively, for lung and pancreas, attaining an epithermal neutron flux of 5x108 ncm-2s-1. The boron concentrations were assumed at 100 ppm and 30 ppm, respectively, for lung and pancreas tumors and normal tissues contains 1/10 tumor concentrations. The dose ratios of tumor to normal tissue were 2.5 and 2.4, respectively, for lung and pancreas. The dose evaluation suggests that BNCT could be applied for both lung and pancreas cancer treatment. (author)

  20. Liposome and co-spray-dried PVP / o-carborane formulations for BNCT treatment of cancer

    OpenAIRE

    Olusanya, Temidayo; Stich, Theresia; Higgins, Samantha Caroline; Lloyd, Rhiannon Eleanor Iris; Pilkington, Geoffrey John; Fatouros, Dimitrios; Calabrese, Gianpiero; Smith, James Richard; Tsibouklis, John

    2015-01-01

    Purpose: Boron neutron capture therapy (BNCT) is a method for selectively destroying malignant (normally glioma) cells whilst sparing normal tissue. Irradiation of 10B (large neutron capture cross-section) with thermal neutrons effects the nuclear fission reaction: 10B + 1n → → 7Li+ + α + γ; where the penetration of α-particles and 7Li+ is only 8 and 5 µm, respectively, i.e., within a single cell thickness. Poor selectivity is the main reason why BNCT has not become a mainstream cancer therap...

  1. Intracellular targeting of mercaptoundecahydrododecaborate (BSH) to malignant glioma by transferrin-PEG liposomes for boron neutron capture therapy (BNCT)

    International Nuclear Information System (INIS)

    Malignant glioma is one of the most difficult tumor to control with usual therapies. In our institute, we select boron neutron capture therapy (BNCT) as an adjuvant radiation therapy after surgical resection. This therapy requires the selective delivery of high concentration of 10B to malignant tumor tissue. In this study, we focused on a tumor-targeting 10B delivery system (BDS) for BNCT that uses transferrin-conjugated polyethylene-glycol liposome encapsulating BSH (TF-PEG liposome-BSH) and compared 10B uptake of the tumor among BSH, PEG liposome-BSH and TF-PEG liposome-BSH. In vitro, we analyzed 10B concentration of the cultured human U87Δ glioma cells incubated in medium containing 20 μg 10B/ml derived from each BDS by inductively coupled plasma atomic emission spectrometry (ICP-AES). In vivo, human U87Δ glioma-bearing nude mice were administered with each BDS (35mg 10B/kg) intravenously. We analyzed 10B concentration of tumor, normal brain and blood by ICP-AES. The TF-PEG liposome-BSH showed higher absolute concentration more than the other BDS. Moreover, TF-PEG liposome-BSH decreased 10B concentration in blood and normal tissue while it maintained high 10B concentration in tumor tissue for a couple of days. This showed the TF-PEG liposome-BSH caused the selective delivery of high concentration of 10B to malignant tumor tissue. The TF-PEG liposome-BSH is more potent BDS for BNCT to obtain absolute high 10B concentration and good contrast between tumor and normal tissue than BSH and PEG liposome-BSH. (author)

  2. Accelerator-based BNCT

    International Nuclear Information System (INIS)

    The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. In particular, the present status and recent progress of the Argentine project will be reviewed. The topics will cover: intense ion sources, accelerator tubes, transport of intense beams, beam diagnostics, the 9Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA), a treatment room, and treatment planning in realistic cases. - Highlights: • The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. • Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. • The present status and recent progress of the Argentine project will be reviewed. • Topics cover intense ion sources, accelerator tubes, transport of intense beams and beam diagnostics, among others

  3. Neutron dosimetry for rat irradiations

    International Nuclear Information System (INIS)

    Monoenergetic neutron irradiations of rats described in last year's Annual Report (COO-4733-1) were continued in collaboration with the Department of Radiology of Thomas Jefferson University. Three groups of 24 rats received absorbed doses of 0.43 MeV neutrons corresponding to 300, 400, or 560 mGy (30, 40, or 56 rad), respectively, of total tissue kerma in free air at the center of the animal positions. In all cases the absorbed dose contributed by gamma rays was about 3 percent of the total absorbed dose. In order to alleviate some of the traumatic effects of the experimental procedure upon the pregnant rats, extra air holes were drilled in the aluminum end caps of the rat holders, thus providing increased ventilation for respiration and cooling. It was also found to be desirable to postpone transporting them for one day after irradiation

  4. Study of the relative dose-response of BANG-3[reg] polymer gel dosimeters in epithermal neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Uusi-Simola, J [Department of Radiology, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Savolainen, S [Department of Radiology, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Kangasmaeki, A [Department of Radiology, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Heikkinen, S [Department of Laboratory Diagnostics, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Perkioe, J [Department of Radiology, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Ramadan, U Abo [Department of Laboratory Diagnostics, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Seppaelae, T [Department of Oncology, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Karila, J [Department of Oncology, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Seren, T [VTT Processes, Technical Research Centre of Finland, FIN-02044 VTT, Finland (Finland); Kotiluoto, P [VTT Processes, Technical Research Centre of Finland, FIN-02044 VTT, Finland (Finland); Sorvari, P [Department of Laboratory Diagnostics, Helsinki University Central Hospital, FIN-00029 HUS (Finland); Auterinen, I [VTT Processes, Technical Research Centre of Finland, FIN-02044 VTT, Finland (Finland)

    2003-09-07

    Polymer gels have been reported as a new, potential tool for dosimetry in mixed neutron-gamma radiation fields. In this work, BANG-3 (MGS Research Inc.) gel vials from three production batches were irradiated with 6 MV photons of a Varian Clinac 2100 C linear accelerator and with the epithermal neutron beam of the Finnish boron neutron capture therapy (BNCT) facility at the FiR 1 nuclear reactor. The gel is tissue equivalent in main elemental composition and density and its T2 relaxation time is dependent on the absorbed dose. The T2 relaxation time map of the irradiated gel vials was measured with a 1.5 T magnetic resonance (MR) scanner using spin echo sequence. The absorbed doses of neutron irradiation were calculated using DORT computer code, and the accuracy of the calculational model was verified by measuring gamma ray dose rate with thermoluminescent dosimeters and {sup 55}Mn(n,{gamma}) activation reaction rate with activation detectors. The response of the BANG-3 gel dosimeter for total absorbed dose in the neutron irradiation was linear, and the magnitude of the response relative to the response in the photon irradiation was observed to vary between different gel batches. The results support the potential of polymer gels in BNCT dosimetry, especially for the verification of two- or three-dimensional dose distributions.

  5. Design of a model for BSA to meet free beam parameters for BNCT based on multiplier system for D–T neutron source

    International Nuclear Information System (INIS)

    Highlights: ► The possibility of using natural uranium as a neutron multiplier for D–T neutron generator is examined. ► To optimize output neutron beam, a moderator/filter/reflector arrangement was designed. ► The MCNP4C code has been used for BSA optimization and other simulations. ► The results show that using this system the BNCT in-air recommended parameters are met. - Abstract: Extensive research has recently been carried out for the development of high-energy D–T neutron generators as neutron sources for BNCT. The energy of these high-energy neutrons must be reduced by designing a Beam Shaping Assembly (BSA) to make them usable for BNCT. However, the neutron flux decreases drastically as neutrons pass through different materials of BSA. Therefore, it is very important to find ways to treat the neutrons economically. In this paper the possibility of using natural uranium as a neutron multiplier is investigated in order to increase the number of neutrons emitted from D–T neutron generator. According to the simulations and performed calculations, a sphere containing natural uranium as neutron multiplier was used to increase the number of neutrons generated by the D–T neutron generator. The energy of fast neutrons that are generated by D–T fusion reaction and amplified by neutron multiplier system is decreased using proper materials as moderators and fast neutron filters in BSA. The gamma rays which are generated as a result of neutron interaction with moderators are removed from neutron spectrum using bismuth as the gamma filter. Also, a thermal neutron absorber omits undesired low-energy neutrons which lead to a high radiation dose for the skin and soft tissues. The results show that passing neutrons through such a BSA causes the establishment of free beam parameters yet the reduction of the output beam intensity is unavoidable. The neutron spectrum related to our BSA has a proper epithermal flux and the fast and thermal neutron fluxes are

  6. Medical chemistry of boron neutron capture agents having pharmacological activity

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a cancer treatment that selectively destroys cancer cells following administering a cancer-selective drug containing stable isotope boron-10 and neutron irradiation. In clinical trial of BNCT, disodium mercaptoundecahydro-closo-dodecaborate (BSH) and p-boronophenylalanine (BPA) have been used, however, development of a new drugs with high cancer selectivity and therapeutic efficiency is expected. Therefore, we review boron-containing drugs as a boron neutron capture agents having pharmacological activity, BNCT research on boron-modified porphyrin derivatives which have photosensitivity and neutron capture activity and our proposed neutron sensitizing agent. (author)

  7. Microdosimetry study of THOR BNCT beam using tissue equivalent proportional counter

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a cancer treatment modality using a nuclear reactor and a boron compound drug. In Taiwan, Tsing Hua open-pool reactor (THOR) has been modulated for the basic research of BNCT for years. A new BNCT beam port was built in 2004 and used to prepare the first clinical trial in the near future. This work reports the microdosimetry study of the THOR BNCT beam by means of the tissue equivalent proportional counter (TEPC). Two self-fabricated TEPCs (the boron-doped versus the boron-free counter wall) were introduced. These dual TEPCs were applied to measure the lineal energy distributions in air and water phantom irradiated by the THOR BNCT mixed radiation field. Dose contributions from component radiations of different linear energy transfers (LETs) were analyzed. Applying a lineal energy dependent biological weighting function, r(y), to the total and individual lineal energy distributions, the effective relative biological effectiveness (RBE), neutron RBE, photon RBE, and boron capture RBE (BNC RBE) were all determined at various depths of the water phantom. Minimum and maximum values of the effective RBE were 1.68 and 2.93, respectively. The maximum effective RBE occurred at 2 cm depth in the phantom. The average neutron RBE, photon RBE, and BNC RBE values were 3.160±0.020, 1.018±0.001, and 1.570±0.270, respectively, for the THOR BNCT beam.

  8. INEL BNCT Program

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, A.L. (ed.)

    1991-08-01

    This Bulletin presents a summary of accomplishments and highlights in the Idaho National Engineering Laboratory's (INEL) Boron Neutron Capture Therapy (BNCT) Program for August 1991. This bulletin includes information on the brain tumor and melanoma research programs, Power Burst Facility (PBF) technical support and modifications, PBF operations, and updates to the animal data charts.

  9. Clinical BNCT, where are we and where should we be going?

    International Nuclear Information System (INIS)

    The future in cancer treatment is with dedicated targeted therapies, selectively destroying tumour cells whilst sparing surrounding healthy tissue, so leading to increased efficacy and decreased toxicity. Boron Neutron Capture Therapy (BNCT) is a radiotherapeutic modality that through the limited spatial distribution of its effects provides a highly selective delivery of dose. It exploits the ability of the non-radioactive isotope boron-10 to readily capture thermal neutrons, to immediately produce particles with high Linear Energy Transfer, high Relative Biological Effectiveness and a limited range in tissue of 10 microns. In addition BNCT offers physical targeting methods such as optimised beam delivery and extra-corporal irradiation, which makes the global approach even more likely to succeed than cellular targeting based on a drug only approach. To be effective, B-10 has to be delivered selectively to the target cells, which is not the case at present in BNCT. Currently, clinical BNCT has been proven feasible using different neutron beams and clinical approaches (intraoperative, external beam and extracorporal irradiation), pharmacokinetic studies including tissue uptake evaluation and phase I trials have been performed using the drugs BSH and BPA. The efficacy of BNCT has been shown in single cases and phase II trials are now open for patient recruitment. In order to develop BNCT further, dedicated trial strategies have to be developed that allow the investigation of this binary treatment modality. Special emphasis has to be spent to the development of new targeting compounds, which is especially difficult because the drugs by themselves do not have any effect. If one day BNCT has been proven to be in specific situations superior to conventional treatments, then cheap and hospital based neutron sources must become available in order to introduce it in routine

  10. Design and characterization of a novel neutron shield for BNCT in an experimental model of oral cancer in the hamster cheek pouch at RA-3

    International Nuclear Information System (INIS)

    Our research group at the Radiation Pathology Division of the Department of Radiobiology (National Atomic Energy Commission) has previously demonstrated the therapeutic efficacy of different BNCT protocols to treat oral cancer in an experimental hamster cheek pouch model. In particular, to perform studies in this experimental model at the thermal facility constructed at RA-3, we designed and constructed a shielding device for thermal neutrons, to be able to expose the cheek pouch while minimizing the dose to the rest of the body. This device allowed for the irradiation of one animal at a time. Given the usage rate of the device, the aim of the present study was to design and construct an optimized version of the existing shielding device that would allow for the simultaneous irradiation of 2 animals at the thermal facility of RA-3. Taking into account the characteristics of the neutron source and preliminary biological assays, we designed the shielding device for the body of the animal, i.e. a rectangular shaped box with double acrylic walls. The space between the walls contains a continuous filling of 6Li2CO3 (95% enriched in 6Li), approximately 6 mm thick. Two small windows interrupt the shield at one end of the box through which the right pouch of each hamster is everted out onto an external acrylic shelf for exposure to the neutron flux. The characterization of the shielding device showed that the neutron flux was equivalent at both irradiation positions confirming that we were able to design and construct a new shielding device that allows for the irradiation of 2 animals at the same time at the thermal facility of RA-3. This new version of the shielding device will reduce the number of interventions of the reactor operators, reducing occupational exposure to radiation and will make the procedure more efficient for researchers. In addition, we addressed the generation of tritium as a product of the capture reaction in lithium. It was considered as a potential

  11. Effect neutron irradiation on glassy carbon

    International Nuclear Information System (INIS)

    Consideration is being given to change of mass (m), volume (v), specific electric resistance (ρ), coefficient of linear thermal expansion (α), dynamic elasticity modulus (E), bending strength (σ) of glassy carbon materials under neutron irradiation. It is shown that neutron irradiation of glassy carbon leads to its shrinkage, accompanied by material disordering. Shrinkage and disordering of glassy carbon decrease with growth both of temperature of material treatment and irradiation temperature

  12. Study on neutron irradiation behavior of beryllium as neutron multiplier

    Energy Technology Data Exchange (ETDEWEB)

    Ishitsuka, Etsuo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1998-03-01

    More than 300 tons beryllium is expected to be used as a neutron multiplier in ITER, and study on the neutron irradiation behavior of beryllium as the neutron multiplier with Japan Materials Testing Reactor (JMTR) were performed to get the engineering data for fusion blanket design. This study started as the study on the tritium behavior in beryllium neutron reflector in order to make clear the generation mechanism on tritium of JMTR primary coolant since 1985. These experiences were handed over to beryllium studies for fusion study, and overall studies such as production technology of beryllium pebbles, irradiation behavior evaluation and reprocessing technology have been started since 1990. In this presentation, study on the neutron irradiation behavior of beryllium as the neutron multiplier with JMTR was reviewed from the point of tritium release, thermal properties, mechanical properties and reprocessing technology. (author)

  13. The 250 kW FiR 1 TRIGA research reactor - International role in Boron Neutron Capture Therapy (BNCT) and regional role in isotope production, education and training

    International Nuclear Information System (INIS)

    The Finnish TRIGA reactor, FiR 1, has been in operation since 1962. From its early days the reactor created versatile research to support both the national nuclear program as well as generally the industry and health care sector. The volume of neutron activation analysis was impressive in the 70's and 80's. In the 1990's a BNCT treatment facility was build at the FiR 1 reactor. The treatment environment is of world top quality after a major renovation of the whole reactor building in 1997. Over one hundred patient irradiations have been performed since May 1999. FiR 1 is one of the few facilities in the world providing this kind of treatments. Due to the BNCT project FiR 1 has become an important research and education unit for medical physics. Education and training play also a role at FiR 1 in the form of university courses and training of nuclear industry personnel. Isotopes for tracer studies are produced normally twice a week. The reactor is operated by four reactor operators and five shift supervisors; this in addition to their work as research scientists or research engineers. (author)

  14. BNCT of canine osteosarcoma

    International Nuclear Information System (INIS)

    A dog was diagnosed with osteosarcoma (8x6x5cm) in the right wing of ilium by radiography, radionuclide scintigraphy and histological study of biopsy material. The treatment plan was as follows: γ-therapy in combination with chemotherapy; prevention of hematogenous pulmonary metastases by the transfusion of 130 ml of allogenic marrow from a healthy donor; administration of 11.4g 10B-boronphenylalanine into the right iliac artery; resection of the right iliac wing with the osteosarcoma lesion; neutron irradiation (MEPhI Reactor) of the bone fragment (dose on healthy osteocytes - 15±4 Gy (W), on tumor - 50±9 Gy (W); reimplantation and fixation of the fragment; three courses of adjuvant chemotherapy. The doses were determined in full-scale calculations of the reactor radiation fields with a model of the bone under the code RADUGA. The 10B concentration (μg/g) in the bone was: normal tissue - 9±3, tumor - 28±5. In 24 hours post operation the dog was able to walk using the treated limb, and 6 months later it moved freely. The patient has been under observation for 30 months. The results of the research demonstrate complete cure. The use of similar treatment plans improves the therapeutic efficiency of BNCT. (author)

  15. Passive neutron assay of irradiated nuclear fuels

    International Nuclear Information System (INIS)

    Passive neutron assay of irradiated nuclear fuel has been investigated by calculations and experiments as a simple, complementary technique to the gamma assay. From the calculations it is found that the neutron emission arises mainly from the curium isotopes, the neutrons exhibit very good penetrability of the assemblies, and the neutron multiplication is not affected by the burnup. From the experiments on BWR and PWR assemblies, it is found that the neutron emission rate is proportional to burnup raised to 3.4 power. Recent investigations indicate that the passive neutron assay is a simple and useful technique to determine the consistency of burnups between assemblies. 10 refs

  16. Passive neutron assay of irradiated nuclear fuels

    International Nuclear Information System (INIS)

    Passive neutron assay of irradiated nuclear fuel has been investigated by calculations and experiments as a simple, complementary technique to the gamma assay. From the calculations it was found that the neutron emission arises mainly from the curium isotopes, the neutrons exhibit very good penetrability of the assemblies, and the neutron multiplication is not affected by the burnup. From the experiments on BWR and PWR assemblies, the neutron emission rate is proportional to burnup raised to 3.4 power. The investigations indicate that the passive neutron assay is a simple and useful technique to determine the consistency of burnups between assemblies

  17. Calculations of neutron flux for BNCT facility of typical working core Multipurpose Reactor (RSG-GAS) using MCNP4B Code

    International Nuclear Information System (INIS)

    Calculation of neutron flux distributions of RSG-GAS typical working core using MCNP 4b Code has been done. Prior to the calculations, modelling of fuel element of meat as well as surfaces of cladding cell and geometry should be made. The model was then included water as a containment also developed. To achieve neutron flux behavior, it was simulated 200,000 to 2,000,000 neutrons. The calculation results indicated that the neutron flux in TWC core is in the order of 1014. Meanwhile, the best flux order for the BNCT facility should be in the order of 1010. With the use of any method, such as constructing of shielding and collimator, the order of neutron flux will decrease. In the previous research in 2001, the results showed the neutron flux in the order of 1010 by installing the collimator with 45 cm thick, made of Pb and 380 cm from the core centre. The results of this research completed with the research done in 2001, 2000 and 1999 certainly support the possibility to construct the BNCT facility in RSG-GAS reactor core

  18. BNCT-Project at the Finnish TRIGA Reactor

    International Nuclear Information System (INIS)

    An epithermal neutron irradiation station for the Boron Neutron Capture Therapy (BNCT) will be constructed in the thermal column of the Finnish Triga reactor. The first target of the BNCT at FiR 1 is the treatment of malignant brain tumors. The epithermal neutrons have the capability to penetrate deep into the brain tissue thermalizing at the same time. The thermal neutrons are captured by 10B-nuclei situated ideally in the tumor cells only and thus the reaction products destroy selectively only the tumor cells. The graphite filling of the thermal column will be replaced by a special moderator material: Al+AlF3. The moderator material and its thickness has been chosen so that the system produces as much as possible epithermal neutrons with low fast neutron and gamma contamination. Both fast neutrons and gamma radiation are harmful for the patient. To reduce the gamma radiation there is a lead-bismuth gamma shield at the outer end of the moderator block. In spite of the low power (250 kW) of the reactor the needed epithermal neutron dose to destroy the tumor will be accumulated in a reasonable time e.g. 0.5 to 1.5 h. This is possible because of the rather short distance between the reactor core and the irradiation target. (author)

  19. Prompt gamma and neutron detection in BNCT utilizing a CdTe detector.

    Science.gov (United States)

    Winkler, Alexander; Koivunoro, Hanna; Reijonen, Vappu; Auterinen, Iiro; Savolainen, Sauli

    2015-12-01

    In this work, a novel sensor technology based on CdTe detectors was tested for prompt gamma and neutron detection using boronated targets in (epi)thermal neutron beam at FiR1 research reactor in Espoo, Finland. Dedicated neutron filter structures were omitted to enable simultaneous measurement of both gamma and neutron radiation at low reactor power (2.5 kW). Spectra were collected and analyzed in four different setups in order to study the feasibility of the detector to measure 478 keV prompt gamma photons released from the neutron capture reaction of boron-10. The detector proved to have the required sensitivity to detect and separate the signals from both boron neutron and cadmium neutron capture reactions, which makes it a promising candidate for monitoring the spatial and temporal development of in vivo boron distribution in boron neutron capture therapy. PMID:26249745

  20. New facility for post irradiation examination of neutron irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Ishitsuka, Etsuo; Kawamura, Hiroshi [Oarai Research Establishment, Ibaraki-Ken (Japan)

    1995-09-01

    Beryllium is expected as a neutron multiplier and plasma facing materials in the fusion reactor, and the neutron irradiation data on properties of beryllium up to 800{degrees}C need for the engineering design. The acquisition of data on the tritium behavior, swelling, thermal and mechanical properties are first priority in ITER design. Facility for the post irradiation examination of neutron irradiated beryllium was constructed in the hot laboratory of Japan Materials Testing Reactor to get the engineering design data mentioned above. This facility consist of the four glove boxes, dry air supplier, tritium monitoring and removal system, storage box of neutron irradiated samples. Beryllium handling are restricted by the amount of tritium;7.4 GBq/day and {sup 60}Co;7.4 MBq/day.

  1. Application of a Bonner sphere spectrometer for the determination of the angular neutron energy spectrum of an accelerator-based BNCT facility

    International Nuclear Information System (INIS)

    Experimental activities are underway at INFN Legnaro National Laboratories (LNL) (Padua, Italy) and Pisa University aimed at angular-dependent neutron energy spectra measurements produced by the 9Be(p,xn) reaction, under a 5 MeV proton beam. This work has been performed in the framework of INFN TRASCO-BNCT project. Bonner Sphere Spectrometer (BSS), based on 6LiI (Eu) scintillator, was used with the shadow-cone technique. Proper unfolding codes, coupled to BSS response function calculated by Monte Carlo code, were finally used. The main results are reported here. - Highlights: • Bonner sphere spectrometer is used to determine the angular neutron energy spectrum of an accelerator-based BNCT facility. • The shadow-cone technique is a method used with Bonner sphere spectrometer to remove the neutron scattered contribution. • The response function matrix for the set of Bonner sphere spectrometer is calculated by Monte Carlo code. • Unfolding codes are used to obtain neutron spectra at different neutron emission angles (0°, 40°, 80° and 120°)

  2. Treatment Planning Systems for BNCT Requirements and Peculiarities

    CERN Document Server

    Daquino, G G

    2003-01-01

    The main requirements and peculiarities expected from the BNCT-oriented treatment planning system (TPS) are summarized in this paper. The TPS is a software, which can be integrated or composed by several auxiliary programs. It plays important roles inside the whole treatment planning of the patient's organ in BNCT. However, the main goal is the simulation of the irradiation, in order to obtain the optimal configuration, in terms of neutron spectrum, patient positioning and dose distribution in the tumour and healthy tissues. The presence of neutrons increases the level of complexity, because much more nuclear reactions need to be monitored and properly calculated during the simulation of the patient's treatment. To this purposes several 3D geometry reconstruction techniques, generally based on the CT scanning data, are implemented and Monte Carlo codes are normally used. The TPSs are expected to show also the results (basically doses and fluences) in a proper format, such as isocurves (or isosurfaces) along t...

  3. First clinical results on the finnish study on BPA-mediated BNCT in glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Kankaanranta, L. [Helsinki University Hospital, Dept. of Oncology, Helsinki (Finland); Seppaelae, T. [University of Helsinki, Department of Physics, Helsinki (Finland); Kallio, M. [Helsinki University Hospital, Dept. of Neurology, Helsinki (Finland)] [and others

    2000-10-01

    An open phase I dose-escalation boron neutron capture therapy (BNCT) study on glioblastoma multiforme (GBM) was initiated at the BNCT facility FiR 1, Espoo, Finland, in May 1999. The aim of the study is to investigate the safety of boronophenylalanine (BPA)-mediated BNCT. Ten GBM patients were treated with a 2-field treatment plan using one fraction. BPA-F was used as the {sup 10}B carrier infused as a fructose solution 290 mg BPA/kg over 2-hours prior to irradiation with epithermal neutrons. Average doses to the normal brain, contrast enhancing tumour, and the target ranged from 3.0 to 5.6 Gy (W), from 35.1 to 66.7 Gy (W), and from 29.6 to 53.6 Gy (W), respectively. BNCT was associated with acceptable toxicity. The median follow-up is 9 months (range, 3 to 16 months) post diagnosis in July 2000. Seven of the 10 patients have recurrent or persistent GBM, and the median time to progression is 8 months. Only one patient has died, and the estimated 1-year overall survival is 86%. Five of the recurrent tumours were treated with external beam photon radiation therapy to the total dose of 30-40 Gy with few acute side-effects. These preliminary findings suggest that acute toxicity of BPA-mediated BNCT is acceptable when average brain doses of 5.6 Gy (W) or less are used. The followup time is too short to evaluate survival, but the estimated 1-year survival of 86% achieved with BNCT followed by conventional photon irradiation at the time of tumour progression is encouraging and emphasises the need of further investigation of BPA-mediated BNCT. (author)

  4. In vitro neutron irradiation of glioma and endothelial cultured cells

    Energy Technology Data Exchange (ETDEWEB)

    Menichetti, L. [Department of PET and Radiopharmaceutical Chemistry, C.N.R. Institute of Clinical Physiology, Pisa (Italy)], E-mail: luca.menichetti@ifc.cnr.it; Gaetano, L. [University Scuola Superiore Sant' Anna, Pisa (Italy); Zampolli, A.; Del Turco, S. [Department of PET and Radiopharmaceutical Chemistry, C.N.R. Institute of Clinical Physiology, Pisa (Italy); Ferrari, C. [University of Pavia, Department of Surgery, Laboratory of experimental Surgery, Pavia (Italy); Bortolussi, S.; Stella, S.; Altieri, S. [University of Pavia, Department of Nuclear Physics, Pavia (Italy); National Institute for Nuclear Physics (INFN), Section of Pavia (Italy); Salvadori, P.A. [Department of PET and Radiopharmaceutical Chemistry, C.N.R. Institute of Clinical Physiology, Pisa (Italy); Cionini, L. [Unit of Radiotherapy, AOUP-University Hospital, Pisa (Italy)

    2009-07-15

    To fully develop its potential boron neutron capture therapy (BNCT) requires the combination of a suitable thermal/epithermal neutron flux together with a selective intake of {sup 10}B-boron nuclei in the target tissue. The latter condition is the most critical to be realized as none of the boron carriers used for experimental or clinical purposes proved at the moment an optimal selectivity for cancer cells compared to normal cells. In addition to complex physical factors, the assessment of the intracellular concentration of boron represent a crucial parameter to predict the dose delivered to the cancer cells during the treatment. Nowadays the dosimetry calculation and then the prediction of the treatment effectiveness are made using Monte Carlo simulations, but some of the model assumption are still uncertain: the radiobiological dose efficacy and the probability of tumour cell survival are crucial parameters that needs a more reliable experimental approach. The aim of this work was to evaluate the differential ability of two cell lines to selectively concentrate the boron-10 administered as di-hydroxyboryl-phenylalanine (BPA)-fructose adduct, and the effect of the differential boron intake on the damage produced by the irradiation with thermal neutrons; the two cell lines were selected to be representative one of normal tissues involved in the active/passive transport of boron carriers, and one of the tumour. Recent in vitro studies demonstrated how BPA is taken by proliferating cells, however the mechanism of BPA uptake and the parameters driving the kinetics of influx and the elimination of BPA are still not clarified. In these preliminary studies we analysed the survival of F98 and human umbilical vein endothelial cells (HUVEC) cells line after irradiation, using different thermal fluencies at the same level of density population and boron concentration in the growing medium prior the irradiation. This is first study performed on endothelium model obtained by

  5. Tumor blood vessel "normalization" improves the therapeutic efficacy of boron neutron capture therapy (BNCT) in experimental oral cancer

    Energy Technology Data Exchange (ETDEWEB)

    D. W. Nigg

    2012-01-01

    We previously demonstrated the efficacy of BNCT mediated by boronophenylalanine (BPA) to treat tumors in a hamster cheek pouch model of oral cancer with no normal tissue radiotoxicity and moderate, albeit reversible, mucositis in precancerous tissue around treated tumors. It is known that boron targeting of the largest possible proportion of tumor cells contributes to the success of BNCT and that tumor blood vessel normalization improves drug delivery to the tumor. Within this context, the aim of the present study was to evaluate the effect of blood vessel normalization on the therapeutic efficacy and potential radiotoxicity of BNCT in the hamster cheek pouch model of oral cancer.

  6. Thermal reference neutron flux irradiation facility development

    International Nuclear Information System (INIS)

    The development of the nuclear energy imposed the knowledge with high accuracy of the neutron characteristics in the nuclear reactors, both for control and safety and for the calibration of the apparatus working in the neutron fields. In order to standardize the neutron measurements, different nuclear facilities producing reproducible neutron fields were created with different neutron characteristics. The object of our project is to develop the reference thermal neutron irradiation facility at the steady state core of the Romanian TRIGA Reactor. The reference thermal neutron irradiation facility consists in a dry spherical cavity (50 cm diameter) placed into the graphite thermal column of the TRIGA-SSR core. The implementation of the irradiation facility into the under water thermal column has represented an important challenge in point of instrumentation solutions. In this paper the development of experimental devices, the local flux monitoring system and the thermal flux cavity neutron characterization results are presented. The available neutron flux density ranges between 2·1010 and 5·1014 neutrons/m2·s. The main spectral characteristics are the cadmium ratio for 197Au(n,γ) reaction 52.1±3% and neutron spectrum temperature = (37 ± 4) deg C. The neutron flux and spectrum measurements have been performed using foil activation techniques and fission rate measurements by sealed fission chambers, followed by spectrum unfolding procedure. The absolute fission reaction measurements, using calibrated fission chambers, allows the neutron flux density unit transfer from international reference neutron fields. The fission chambers have been calibrated during international intercomparison programs and have been used for measurements in the reference facilities from CEN/SCK Mol. (authors)

  7. Near-threshold 7Li(p,n)7Be neutrons on the practical conditions using thick Li-target and Gaussian proton energies for BNCT

    International Nuclear Information System (INIS)

    The near threshold 7Li(p,n)7Be neutrons generated by incident proton energy having Gaussian distribution with mean energies from 1.85 to 1.95 MeV, were studied as a practical neutron source for BNCT wherein an RFQ accelerator and a thick Li-target are used. Gaussian energy distributions with the standard deviation of 0, 10, 20 and 40 keV for mean proton energies from 1.85 to 1.95 MeV were surveyed in 0.01 MeV increments. A thick liquid Li-target whose dimensions were established in our previous experiments (i.e., 1 mm-thick with 50 mm width and 50 mm length) was considered in this study. The suitable incident proton energy and physical dimensions of Pb layer which serves as a gamma absorber and a Polyethylene layer which is used as a BDE were surveyed by means of the concepts of TPD. Dose distribution were calculated by using MCNP5. A proton beam with mean energy of 1.92 MeV and a Gaussian energy distribution with a standard deviation of 20 keV at a current of 10 mA was selected from the viewpoint of irradiation time and practically achievable proton current. The suitable thicknesses of Pb gamma absorber was estimated to be about 3 cm. The estimated thickness of the polyethylene BDE was about 24 mm for an ideal proton current of 13 mA, and was 18 mm for a practical proton current of 10 mA. - Highlights: • Proton enrgy from 1.85 to 1.95 MeV were studied for near threshold 7Li(p,n)7Be neutrons. • Practical conditions were applied for RFQ type accelerator and a thick Li-target. • Gaussian distribution of proton energies were checked for the standard deviation of 0, 10, 20 and 40 keV. • The mean energy of 1.92 MeV protons with Gaussian distribution of 20 keV was feasible. • The suitable thicknesses of Lead layer as gamma absorber was about 3 cm. • The suitable thicknesses of polyethylene BDE was about 24 mm at the proton current of 13 mA

  8. Preliminary modeling of BNCT beam tube on IRT in Sofia

    Energy Technology Data Exchange (ETDEWEB)

    Belousov, S. [Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Tsarigradsko 72, Sofia (Bulgaria)], E-mail: belousov@inrne.bas.bg; Ilieva, K. [Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Tsarigradsko 72, Sofia (Bulgaria)

    2009-07-15

    The technical design of the research reactor IRT in Sofia is in progress. It includes an arrangement for a BNCT facility for tumor treatment. Modeling of geometry and material composition of filter/collimator for the BNCT beam tube on IRT has been carried out following the beam tube configuration of the Massachusetts Institute of Technology Reactor [Harling et al., 2002. The fission converter-based epithermal neutron irradiation facility at the Massachusetts Institute of Technology Reactor. Nucl. Sci. Eng. 140, 223-240.] and taking into account an ability to include the tube into the IRT reactor geometry. The results of neutron and gamma transport calculations performed for the model have shown that the facility will be able to supply an epithermal neutron flux of about 5x10{sup 9} n cm{sup -2} s{sup -1}, with low contamination from fast neutrons and gamma rays that would be among the best facilities currently available. An optimiziation study has been performed for the beam collimator, following similar studies for the TAPIRO research reactor in Italy. [Nava et al., 2005. Monte Carlo optimization of a BNCT facility for treating brain gliomas at the TAPIRO reactor. Radiat. Prot. Dosim. 116 (1-4), 475-481.].

  9. Preliminary modeling of BNCT beam tube on IRT in Sofia

    International Nuclear Information System (INIS)

    The technical design of the research reactor IRT in Sofia is in progress. It includes an arrangement for a BNCT facility for tumor treatment. Modeling of geometry and material composition of filter/collimator for the BNCT beam tube on IRT has been carried out following the beam tube configuration of the Massachusetts Institute of Technology Reactor [Harling et al., 2002. The fission converter-based epithermal neutron irradiation facility at the Massachusetts Institute of Technology Reactor. Nucl. Sci. Eng. 140, 223-240.] and taking into account an ability to include the tube into the IRT reactor geometry. The results of neutron and gamma transport calculations performed for the model have shown that the facility will be able to supply an epithermal neutron flux of about 5x109 n cm-2 s-1, with low contamination from fast neutrons and gamma rays that would be among the best facilities currently available. An optimiziation study has been performed for the beam collimator, following similar studies for the TAPIRO research reactor in Italy. [Nava et al., 2005. Monte Carlo optimization of a BNCT facility for treating brain gliomas at the TAPIRO reactor. Radiat. Prot. Dosim. 116 (1-4), 475-481.

  10. Characterisation of the TAPIRO BNCT thermal facility

    International Nuclear Information System (INIS)

    Dosimetry and spectrometry measurements have been carried out in the thermal column of the research fast reactor RSV-TAPIRO (ENEA-Casaccia, Rome) in order to investigate its suitability for irradiation of cells or mice, with a view to research in the interests of boron neutron capture therapy (BNCT). The thermal column consists of a graphite moderator (40 cm thick) containing a lead shield (13 cm thick) in order to shield reactor background. The irradiation volume, inside this structure, has cubic shape (18 x 18 x 18 cm3). Besides measurements of fluence and dose rates in air or in phantom performed with thermoluminescence dosemeters (TLDs) and using the activation technique, dose and fluence profiles have been generated using a method based on gel dosemeters analysed with optical imaging. To check the consistency of the results, spectrometry measurements in the same irradiation volume have been performed by means of bubble detectors. (authors)

  11. Dose characterization in radiation mixed field using thermoluminescent dosemeters at the installation for studies on BNCT

    International Nuclear Information System (INIS)

    This work presents the methodology used for characterization of the absorbed dose due to the gamma radiation (in mixed field of neutrons and gamma), at the installation for studies on BNCT, using thermoluminescent dosemeters. Information is supplied concerning to the obtention of the Victoreen 2800M TL reader parameters, used for performing the TLDs readings, and are presented the construction results of the calibration curves for the TLDs 400 and TLDs 700. From these calibration curves it was determined the absorbed dose due to the gamma radiation in the position of sample irradiation at the installation for the BNCT studies

  12. Combined TL and 10B-alanine ESR dosimetry for BNCT.

    Science.gov (United States)

    Bartolotta, A; D'Oca, M C; Lo Giudice, B; Brai, M; Borio, R; Forini, N; Salvadori, P; Manera, S

    2004-01-01

    The dosimetric technique described in this paper is based on electron spin resonance (ESR) detectors using an alanine-boric compound acid enriched with (10)B, and beryllium oxide thermoluminescent (TL) detectors; with this combined dosimetry, it is possible to discriminate the doses due to thermal neutrons and gamma radiation in a mixed field. Irradiations were carried out inside the thermal column of a TRIGA MARK II water-pool-type research nuclear reactor, also used for Boron Neutron Capture therapy (BNCT) applications, with thermal neutron fluence from 10(9) to 10(14) nth cm(-2). The ESR dosemeters using the alanine-boron compound indicated ESR signals about 30-fold stronger than those using only alanine. Moreover, a negligible correction for the gamma contribution, measured with TL detectors, almost insensitive to thermal neutrons, was necessary. Therefore, a simultaneous analysis of our TL and ESR detectors allows discrimination between thermal neutron and gamma doses, as required in BNCT. PMID:15353720

  13. Design of a beam shaping assembly and preliminary modelling of a treatment room for accelerator-based BNCT at CNEA

    International Nuclear Information System (INIS)

    This work reports on the characterisation of a neutron beam shaping assembly (BSA) prototype and on the preliminary modelling of a treatment room for BNCT within the framework of a research programme for the development and construction of an accelerator-based BNCT irradiation facility in Buenos Aires, Argentina. The BSA prototype constructed has been characterised by means of MCNP simulations as well as a set of experimental measurements performed at the Tandar accelerator at the National Atomic Energy Commission of Argentina. - Highlights: ► Characterisation of a neutron beam shaping assembly for accelerator-based BNCT. ► Measurements: total and epi-cadmium neutron fluxes and beam homogeneity. ► Calculations: Monte Carlo simulations with the MCNP code. ► Measured and calculated figure-of-merit parameters in agreement with those of IAEA. ► Initial MCNP dose calculations for a treatment room to define future design actions.

  14. Simulation study of accelerator based quasi-mono-energetic epithermal neutron beams for BNCT.

    Science.gov (United States)

    Adib, M; Habib, N; Bashter, I I; El-Mesiry, M S; Mansy, M S

    2016-01-01

    Filtered neutron techniques were applied to produce quasi-mono-energetic neutron beams in the energy range of 1.5-7.5 keV at the accelerator port using the generated neutron spectrum from a Li (p, n) Be reaction. A simulation study was performed to characterize the filter components and transmitted beam lines. The feature of the filtered beams is detailed in terms of optimal thickness of the primary and additive components. A computer code named "QMNB-AS" was developed to carry out the required calculations. The filtered neutron beams had high purity and intensity with low contamination from the accompanying thermal, fast neutrons and γ-rays. PMID:26474209

  15. Progress in neutron beam development at the HFR Petten (feasibility study for a BNCT facility)

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy, using intermediate energy neutrons to achieve the deep penetration essential for treating brain tumours, can be implemented with a filtered reactor neutron beam. This is designed to minimize the mean energy of the neutrons to keep proton recoil damage to the scalp within normal tissue tolerance limits whilst delivering the required thermal neutron fluence to the tumour over a reasonably short period. This can only be realized in conjunction with a high power density reactor. At the Joint Research Centre Petten an optimized neutron filter is currently being built for installation into the HB11 beam tube of the High Flux Reactor HFR. Part of the development leading to this design has been an extensive study of broad spectrum, filtered beam performance on the HB7 beam tube facility. A wide range of calculations was performed using the Monte Carlo code, MCPN, supported by validation experiments in which several filter configuration incorporating aluminium, sulphur, liquid argon, titanium and cadmium were installed for low power measurements of the neutron fluence rate, neutron spectra and beam gamma-ray contamination. The measurements were carried out within a successful European collaboration. Evaluations were made of the reactor core edge and unfiltered beam spectra, for comparison with MCNP calculations. Multi-foil activation methods and also gamma dose determination in the filtered beam using thermo-luminescent detectors were performed by the ECN. The Harwell/ Birmingham University collaborators undertook the neutron spectrum measurements in the filtered beam. proton recoil spectrometry was used above 30 keV, combined with a multi-sphere and BF3 chamber response modification technique. Subsequent spectrum adjustment was carried out with the SENSAK code. The agreement between the calculated and measured spectra has given confidence in the reactor and filter modelling methods used to design the HB11 therapy facility. (author). 12 refs

  16. SU-E-J-100: Reconstruction of Prompt Gamma Ray Three Dimensional SPECT Image From Boron Neutron Capture Therapy(BNCT)

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, D; Jung, J; Suh, T [The Catholic University of Korea, College of medicine, Department of biomedical engineering (Korea, Republic of)

    2014-06-01

    Purpose: Purpose of paper is to confirm the feasibility of acquisition of three dimensional single photon emission computed tomography (SPECT) image from boron neutron capture therapy (BNCT) using Monte Carlo simulation. Methods: In case of simulation, the pixelated SPECT detector, collimator and phantom were simulated using Monte Carlo n particle extended (MCNPX) simulation tool. A thermal neutron source (<1 eV) was used to react with the boron uptake region (BUR) in the phantom. Each geometry had a spherical pattern, and three different BURs (A, B and C region, density: 2.08 g/cm3) were located in the middle of the brain phantom. The data from 128 projections for each sorting process were used to achieve image reconstruction. The ordered subset expectation maximization (OSEM) reconstruction algorithm was used to obtain a tomographic image with eight subsets and five iterations. The receiver operating characteristic (ROC) curve analysis was used to evaluate the geometric accuracy of reconstructed image. Results: The OSEM image was compared with the original phantom pattern image. The area under the curve (AUC) was calculated as the gross area under each ROC curve. The three calculated AUC values were 0.738 (A region), 0.623 (B region), and 0.817 (C region). The differences between length of centers of two boron regions and distance of maximum count points were 0.3 cm, 1.6 cm and 1.4 cm. Conclusion: The possibility of extracting a 3D BNCT SPECT image was confirmed using the Monte Carlo simulation and OSEM algorithm. The prospects for obtaining an actual BNCT SPECT image were estimated from the quality of the simulated image and the simulation conditions. When multiple tumor region should be treated using the BNCT, a reasonable model to determine how many useful images can be obtained from the SPECT could be provided to the BNCT facilities. This research was supported by the Leading Foreign Research Institute Recruitment Program through the National Research

  17. SU-E-J-100: Reconstruction of Prompt Gamma Ray Three Dimensional SPECT Image From Boron Neutron Capture Therapy(BNCT)

    International Nuclear Information System (INIS)

    Purpose: Purpose of paper is to confirm the feasibility of acquisition of three dimensional single photon emission computed tomography (SPECT) image from boron neutron capture therapy (BNCT) using Monte Carlo simulation. Methods: In case of simulation, the pixelated SPECT detector, collimator and phantom were simulated using Monte Carlo n particle extended (MCNPX) simulation tool. A thermal neutron source (<1 eV) was used to react with the boron uptake region (BUR) in the phantom. Each geometry had a spherical pattern, and three different BURs (A, B and C region, density: 2.08 g/cm3) were located in the middle of the brain phantom. The data from 128 projections for each sorting process were used to achieve image reconstruction. The ordered subset expectation maximization (OSEM) reconstruction algorithm was used to obtain a tomographic image with eight subsets and five iterations. The receiver operating characteristic (ROC) curve analysis was used to evaluate the geometric accuracy of reconstructed image. Results: The OSEM image was compared with the original phantom pattern image. The area under the curve (AUC) was calculated as the gross area under each ROC curve. The three calculated AUC values were 0.738 (A region), 0.623 (B region), and 0.817 (C region). The differences between length of centers of two boron regions and distance of maximum count points were 0.3 cm, 1.6 cm and 1.4 cm. Conclusion: The possibility of extracting a 3D BNCT SPECT image was confirmed using the Monte Carlo simulation and OSEM algorithm. The prospects for obtaining an actual BNCT SPECT image were estimated from the quality of the simulated image and the simulation conditions. When multiple tumor region should be treated using the BNCT, a reasonable model to determine how many useful images can be obtained from the SPECT could be provided to the BNCT facilities. This research was supported by the Leading Foreign Research Institute Recruitment Program through the National Research

  18. Effect of neutron irradiation on vitreous carbon

    International Nuclear Information System (INIS)

    The change in mass (m), volume (V), specific electric resistance (ρ), coefficient of linear thermal expansion (α), dynamic elasticity modulus (E), and limit of bending strength (σ) of vitreous carbon are studied upon neutron irradiation. Samples for study were two forms of vitreous carbon obtained by hardening thermally reactive polymers at 900-1,000 degree K. Phenol-formaldehyde (bakelite lacquer A, Bakelite A) and furfural-phenol-formaldehyde (FM-2) resin were used. They were irradiated in the experimental water - water VVR-M reactor between 360-1,030 degree K. The maximal neutron flux was 1.65·1021 neut/cm2. Neutron irradiation of vitreous carbon led to its shrinkage and accompanied weakening. Shrinkage and weakening of vitreous carbon was decreased with an increase of treatment and irradiation temperatures

  19. Neutron irradiation under continuous BPA injection for solving the problem of heterogeneous distribution of BPA

    International Nuclear Information System (INIS)

    In the current BNCT procedure, the blood 10B levels at the completion of neutron irradiation decrease to 60% level of the start. It is highly probable that such a rapid decrease in the blood 10B levels is expanding the heterogeneity in the micro-distribution of BPA in tumors. Ono and Masunaga previously reported that the combination of BSH is one of solutions for the problem of heterogeneous micro-distribution of BPA. As a similar idea, it is possible to kill tumor cells efficiently by increasing inter-cellular BPA levels. Increase of the blood 10B levels with time becomes less steep by 50%, abruptly at around 30 minutes after the start of BPA. Based on this analysis, we injected BPA 500 mg/kg at the speed of 200 mg/kg/h for initial 2 hours, and decreased the speed to 100 mg/kg/h for remaining 1 hour, and neutron was irradiated during final 1 hour. This protocol was applied to 15 cases. The blood level at the completion of neutron irradiation remained at 96% level of the start on average. Similar stable 10B level condition was made in tumor bearing mice by ligaturing renal arteries. After neutron irradiation, tumor cells were examined on micronucleus appearance. Under normal condition, fraction of the cells without micronuclei decreased with neutron fluence in biphasic pattern. However, in mice without BPA excretion it showed nearly linear curve. This means BPA distributed homogeneously through the tumor. From these data, new BPA injection and neutron irradiation protocol is considered useful to overcome the difficulty of BPA. (author)

  20. Development and characteristics of the HANARO ex-core neutron irradiation facility for applications in the boron neutron capture therapy field

    CERN Document Server

    Kim, M S; Jun, B J; Kim, H; Lee, B C; Hwang, Sung-Yul; Jun, Byung-Jin; Kim, Heonil; Kim, Myong-Seop; Lee, Byung-Chul

    2006-01-01

    The HANARO ex-core neutron irradiation facility was developed for various applications in the boron neutron capture therapy (BNCT) field, and its characteristics have been investigated. In order to obtain a sufficient thermal neutron flux with a low level contamination of fast neutrons and gamma-rays, a radiation filtering method is adopted. The radiation filter has been designed by using a silicon single crystal cooled by liquid nitrogen and a bismuth crystal. The installation of the main components of the irradiation facility and the irradiation room are finished. Experimental measurements of the neutron beam characteristics have been performed by using bare and cadmium covered gold foils and wires. The in-phantom neutron flux distribution was measured for a flux mapping inside the phantom. The gamma-ray dose was determined by using TLD-700 thermoluminescence dosimeters. The thermal and fast neutron fluxes and the gamma-ray dose were calculated by using the MCNP code, and they were compared with experimenta...

  1. Implementation of BNCT treatment planning procedures

    International Nuclear Information System (INIS)

    Estimation of radiation doses delivered during boron neutron capture therapy (BNCT) requires combining data on spatial distribution of both the thermal neutron fluence and the 10B concentration, as well as the relative biological effectiveness of various radiation dose components in the tumor and normal tissues. Using the treatment planning system created at Idaho National Engineering and Environmental Laboratory and the procedures we had developed for clinical trials, we were able to optimize the treatment position, safely deliver the prescribed BNCT doses, and carry out retrospective analyses and reviews. In this paper we describe the BNCT treatment planning process and its implementation in the ongoing dose escalation trials at Brookhaven National Laboratory. (author)

  2. Measurement and simulation of the TRR BNCT beam parameters

    Science.gov (United States)

    Bavarnegin, Elham; Sadremomtaz, Alireza; Khalafi, Hossein; Kasesaz, Yaser; Golshanian, Mohadeseh; Ghods, Hossein; Ezzati, Arsalan; Keyvani, Mehdi; Haddadi, Mohammad

    2016-09-01

    Recently, the configuration of the Tehran Research Reactor (TRR) thermal column has been modified and a proper thermal neutron beam for preclinical Boron Neutron Capture Therapy (BNCT) has been obtained. In this study, simulations and experimental measurements have been carried out to identify the BNCT beam parameters including the beam uniformity, the distribution of the thermal neutron dose, boron dose, gamma dose in a phantom and also the Therapeutic Gain (TG). To do this, the entire TRR structure including the reactor core, pool, the thermal column and beam tubes have been modeled using MCNPX Monte Carlo code. To measure in-phantom dose distribution a special head phantom has been constructed and foil activation techniques and TLD700 dosimeter have been used. The results show that there is enough uniformity in TRR thermal BNCT beam. TG parameter has the maximum value of 5.7 at the depth of 1 cm from the surface of the phantom, confirming that TRR thermal neutron beam has potential for being used in treatment of superficial brain tumors. For the purpose of a clinical trial, more modifications need to be done at the reactor, as, for example design, and construction of a treatment room at the beam exit which is our plan for future. To date, this beam is usable for biological studies and animal trials. There is a relatively good agreement between simulation and measurement especially within a diameter of 10 cm which is the dimension of usual BNCT beam ports. This relatively good agreement enables a more precise prediction of the irradiation conditions needed for future experiments.

  3. Splenomegaly of C57BL/6 mouse by thermal neutron exposure after Borono phenylalanine (BPA) administration

    International Nuclear Information System (INIS)

    BNCT(Boron Neutron Capture Therapy) is a promising clinical method for a kind of tumors by killing cancer cells selectively at the cell level, its research is going on over the world, especially KURRI (Kyoto University Research Reactor Institute) in Japan and MIT (Massachusetts institute of Technology)in USA. For the research in Korea, a neutron irradiation facility was a BNCT facility at Hanaro to support the research of BNCT (basic medical, chemical, physical and biological technology). In the present research, we firstly tried to measure the biological information for the splenomegaly of C57BL/6 mouse by thermal neutron exposure after BPA (boronophenylalanine) admini-stration

  4. Clinical experience of BNCT for brain and skin tumors at Kyoto University Reactor

    International Nuclear Information System (INIS)

    The research nuclear reactor of Kyoto University (KUR), which was established in 1963, has the power of 5 MW and has rendered services to scientists in various fields including biology and medicine. The first clinical application was carried out on a brain tumor patient by Professor Hatanaka in 1974. Eight Japanese, 2 German and one American patients were treated. The ages of patients were 9-66 years and all were male. Skin tumors were irradiated at KUR to measure 10B content in the tissues by Nickel Mirror Neutron Guide Tube (NMNGT) attached to KUR, before BNCT. Except in a few cases, patients had recurrent tumours after previous treatment by chemotherapy, radiotherapy or surgical treatments. The absorbed dose used in the previous radiotherapy before BNCT was a curative dose. The time intervals between previous radiotherapy and BNCT varied. The treated skin tumours included various grades of melanoma. Some cases appeared to be astrocytoma grade IV

  5. The BNCT project in the Czech Republic

    International Nuclear Information System (INIS)

    The start of clinical trials is expected before NCT Osaka 2000. The experiences from different part of project are presented. The BNCT facility at LVR-15 reactor of NRI consists of epithermal neutron beam with improved construction (6.98 x 108/cm2s with acceptable background of fast neutrons and gammas) and irradiation and control rooms equipped by appropriate devices. Internationally-recognized software MacNCTPLAN is utilized for computational dosimetry and treatment planning. In the part of protocol the following parameters have been assessed: patient selection, BSH dosage, fractionation, starting dose, dose escalation steps. At the LVR-15, at horizontal channel, a prompt gamma ray analysis (PGRA) system has been developed and is operated for BNCT purposes. Some human blood samples were analyzed and compared with classical ICP method. During the process of licensing the experience was obtained, some notes are discussed in the paper. The first results were received for the study of biological effect of the LVR source for small animal model. (author)

  6. Genetic Effects of Neutron Irradiation in Mice

    International Nuclear Information System (INIS)

    The limited amount of information already published on this subject, mainly relating to the induction of dominant lethal mutations by fast neutrons at high intensity, is reviewed. Our work is mainly concerned with the genetic effects of fast neutrons at low intensity, using the reactor GLEEP. At a dose-rate of 0.01 rad/min., these fast fission neutrons are about six times as effective as acute X-irradiation for the induction of dominant lethal mutations in spermatozoa. This value, and the linear dose-mutation relationship, are similar to previous findings with neutron irradiation at high intensity. We are also comparing the rate of induction of specific locus mutations in mouse spermatogonia by about 215 rad of fast neutrons (with slight gamma contamination) and 650 rad of Co60 gamma-rays, administered nearly continuously over twelve weeks. Results to date suggest that these neutrons are about 50 times as effective as gamma-rays for the induction of specific locus mutations; they would also appear to be about six times as effective as acute X-irradiation. It is concluded that the type of dose-rate dependence associated with specific locus mutations induced by low LET radiations is most unlikely to occur with high LET ones; in fact it may be reversed. (author)

  7. Reprint of Bioneutronics: Thermal scattering in organics tissues and its impact on BNCT dosimetry.

    Science.gov (United States)

    Ramos, R L; Sztejnberg Gonçalves-Carralves, M L; Cantargi, F

    2015-12-01

    Neutron transport calculation is a key factor in BNCT numerical dosimetry assessments where thermal neutron flux is intimately related to the neutron dose, specially, the therapeutic boron dose. In this work, numerical calculations in phantoms were performed to determine the importance of utilizing the appropriate thermal scattering treatment for different organic tissues. Two thermal treatments for the neutron scattering were included in the simulations: hydrogen bounded in bulk water and hydrogen bounded in a lipid like carbon chain (polyethylene). The results showed difference between both thermal treatments that can reach several percent points depending on the type of source and irradiated geometry. PMID:26515135

  8. Bioneutronics: Thermal scattering in organics tissues and its impact on BNCT dosimetry.

    Science.gov (United States)

    Ramos, R L; Gonçalves-Carralves, M L Sztejnberg; Cantargi, F

    2015-10-01

    Neutron transport calculation is a key factor in BNCT numerical dosimetry assessments where thermal neutron flux is intimately related to the neutron dose, specially, the therapeutic boron dose. In this work, numerical calculations in phantoms were performed to determine the importance of utilizing the appropriate thermal scattering treatment for different organic tissues. Two thermal treatments for the neutron scattering were included in the simulations: hydrogen bounded in bulk water and hydrogen bounded in a lipid like carbon chain (polyethylene). The results showed difference between both thermal treatments that can reach several percent points depending on the type of source and irradiated geometry. PMID:26141296

  9. Experimental and Simulated Characterization of a Beam Shaping Assembly for Accelerator- Based Boron Neutron Capture Therapy (AB-BNCT)

    International Nuclear Information System (INIS)

    In the frame of the construction of a Tandem Electrostatic Quadrupole Accelerator facility devoted to the Accelerator-Based Boron Neutron Capture Therapy, a Beam Shaping Assembly has been characterized by means of Monte-Carlo simulations and measurements. The neutrons were generated via the 7Li(p, n)7Be reaction by irradiating a thick LiF target with a 2.3 MeV proton beam delivered by the TANDAR accelerator at CNEA. The emerging neutron flux was measured by means of activation foils while the beam quality and directionality was evaluated by means of Monte Carlo simulations. The parameters show compliance with those suggested by IAEA. Finally, an improvement adding a beam collimator has been evaluated.

  10. Radiation field characterization of a BNCT research facility using Monte Carlo Method - Code MCNP-4B

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy - BNCT- is a selective cancer treatment and arises as an alternative therapy to treat cancer when usual techniques - surgery, chemotherapy or radiotherapy - show no satisfactory results. The main proposal of this work is to project a facility to BNCT studies. This facility relies on the use of an AmBe neutron source and on a set of moderators, filters and shielding which will provide the best neutron/gamma beam characteristic for these BNCT studies, i.e., high intensity thermal and/or epithermal neutron fluxes and with the minimum feasible gamma rays and fast neutrons contaminants. A computational model of the experiment was used to obtain the radiation field in the sample irradiation position. The calculations have been performed with the MCNP 4B Monte Carlo Code and the results obtained can be regarded as satisfactory, i.e., a thermal neutron fluency ΝΤ = 1,35x108 n/cm2, a fast neutron dose of 5,86x-10 Gy/ΝΤ and a gamma ray dose of 8,30x-14 Gy/ΝΤ. (author)

  11. Thermal annealing in neutron-irradiated tribromobenzenes

    DEFF Research Database (Denmark)

    Siekierska, K.E.; Halpern, A.; Maddock, A. G.

    1968-01-01

    The distribution of 82Br among various products in neutron-irradiated isomers of tribromobenzene has been investigated, and the effect of thermal annealing examined. Reversed-phase partition chromatography was employed for the determination of radioactive organic products, and atomic bromine in the...

  12. Neutron irradiation effects in SiC

    Energy Technology Data Exchange (ETDEWEB)

    Brink, D.J. [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa)], E-mail: johan.brink@up.ac.za; Malherbe, J.B. [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa); Camassel, J. [Groupe d' Etude des Semiconducteurs, University of Montpellier II, Montpellier 34095 (France)

    2009-08-15

    SiC is a wide band gap semiconductor material with potential applications in harsh environmental conditions. In this work we investigate the effects of neutron irradiation on the properties of two SiC polytypes. Changes to the optical properties were analyzed using a range of techniques including visible transmission, infra-red reflectance, Raman spectroscopy and photoluminescence.

  13. Neutron irradiation effects in SiC

    International Nuclear Information System (INIS)

    SiC is a wide band gap semiconductor material with potential applications in harsh environmental conditions. In this work we investigate the effects of neutron irradiation on the properties of two SiC polytypes. Changes to the optical properties were analyzed using a range of techniques including visible transmission, infra-red reflectance, Raman spectroscopy and photoluminescence.

  14. Some structure defects in neutron irradiated fluorphlogopite

    Energy Technology Data Exchange (ETDEWEB)

    Avesov, A.D.; Gasanov, E.M. (AN Uzbekskoj SSR, Tashkent. Inst. Yadernoj Fiziki); Novozhilov, A.I.; Samoilovich, V.I. (Vsesoyuznyj Nauchno-Issledovatel' skij Inst. Sinteza Mineral' nogo Syr' ya, Aleksandrov (USSR))

    1982-09-16

    Structure defects formed in synthetic mica fluorphlogopite KMg/sub 3/(AlSi/sub 3/O/sub 10/)F/sub 2/ with and without Ti admixture under reactor neutron irradiation were investigated by optical absorption and electron paramagnetic resonance spectroscopy.

  15. Assessment of dose rate scaling factors used in NCTPlan treatment planning code for the BNCT beam of THOR

    International Nuclear Information System (INIS)

    Tsing Hua open-pool reactor (THOR) at Tsing Hua University in Taiwan has been used to investigate the feasibility and to enhance the technology of boron neutron capture therapy (BNCT) for years. A rebuilt epithermal beam port for BNCT at THOR was finished in the summer of 2004, and then researches and experiments were performed to hasten the first clinical treatment case of BNCT in Taiwan in the near future. NCTPlan, a Monte Carlo-based clinical treatment planning code, was used to calculate the dose-rate distributions of BNCT in this work. A self-made Snyder head phantom with a servo-motor control system was irradiated in front of the THOR BNCT beam exit. The phantom was made from a 3 mm shell of quartz wool impregnated with acrylic casting resin mounted on an acrylic base, and was filled with water. Gold foils (bare and cadmium-covered) and paired ion chambers (one with graphite wall and filled with CO2 gas, another with A-150 plastic tissue equivalent wall and filled with tissue equivalent gas) were placed inside the Snyder phantom to measure and estimate the depth-dose distributions in the central axis of the beam. Dose components include the contribution of thermal neutrons, fast neutrons, photons and emitted α particles from 10B(n,α)7Li reaction. Comparison and analysis between computed and measured results of depth-dose distributions were made in this work. Dose rate scaling factors (DRSFs) were defined as normalization factors derived individually for each dose component in the BNCT in-phantom radiation field that provide the best agreement between measured and computed data. This paper reports the in-phantom calculated and experimental dosimetry and the determined DRSFs used in NCTPlan code for the BNCT beam of THOR.

  16. Combination of fractionated photon radiation and BNCT

    International Nuclear Information System (INIS)

    Because of the relatively low normal brain dose, BNCT allows additional photon radiation sufficient to maintain a total normal brain dose below the tolerance limit. We started a new protocol with a combination of fractionated, extended local photon radiation, and BPA- and BSH-mediated BNCT. In this protocol, newly diagnosed glioblastoma were treated with BPA (250 mg/kg) - and BSH (100 mg/kg) - mediated BNCT followed by fractionated photon radiation. The BNCT dose for the normal brain was restricted to less than 13 GyEq. The fractionated photon radiation at a dose of 30/15 fr or 30.6 Gy/17 fr was planned to irradiate a T2 high-intensity area of post-BNCT MRI. So far, 6 patients have been treated by this protocol. The clinical course, dose distribution, tumor response, and adverse events will be discussed herein. (author)

  17. Neutron irradiation induced amorphization of silicon carbide

    Energy Technology Data Exchange (ETDEWEB)

    Snead, L.L.; Hay, J.C. [Oak Ridge National Lab., TN (United States)

    1998-09-01

    This paper provides the first known observation of silicon carbide fully amorphized under neutron irradiation. Both high purity single crystal hcp and high purity, highly faulted (cubic) chemically vapor deposited (CVD) SiC were irradiated at approximately 60 C to a total fast neutron fluence of 2.6 {times} 10{sup 25} n/m{sup 2}. Amorphization was seen in both materials, as evidenced by TEM, electron diffraction, and x-ray diffraction techniques. Physical properties for the amorphized single crystal material are reported including large changes in density ({minus}10.8%), elastic modulus as measured using a nanoindentation technique ({minus}45%), hardness as measured by nanoindentation ({minus}45%), and standard Vickers hardness ({minus}24%). Similar property changes are observed for the critical temperature for amorphization at this neutron dose and flux, above which amorphization is not possible, is estimated to be greater than 130 C.

  18. Neutron irradiation induced amorphization of silicon carbide

    International Nuclear Information System (INIS)

    This paper provides the first known observation of silicon carbide fully amorphized under neutron irradiation. Both high purity single crystal hcp and high purity, highly faulted (cubic) chemically vapor deposited (CVD) SiC were irradiated at approximately 60 C to a total fast neutron fluence of 2.6 x 1025 n/m2. Amorphization was seen in both materials, as evidenced by TEM, electron diffraction, and x-ray diffraction techniques. Physical properties for the amorphized single crystal material are reported including large changes in density (-10.8%), elastic modulus as measured using a nanoindentation technique (-45%), hardness as measured by nanoindentation (-45%), and standard Vickers hardness (-24%). Similar property changes are observed for the critical temperature for amorphization at this neutron dose and flux, above which amorphization is not possible, is estimated to be greater than 130 C

  19. BNCT and Targeted Radiotherapy (TRT) developments in Romania

    International Nuclear Information System (INIS)

    There are a number of treatment modalities for cancer including surgery, chemotherapy and radiation therapy. However, these treatments are not always effective. The search for new and more efficient ways to combat cancer has opened new perspectives. Boron neutron capture therapy (BNCT) is a new approach in cancer treatment that has been proposed to combat glioblastomas of the brain, neck cancer and malignant melanomas, tumors that are resistant to traditional cancer therapies. BNCT is based on the 10B(n,α)7Li nuclear reaction, which can potentially deliver a very high and fatal radiation dose to cancerous cells by concentrating boron in them. It is a promising, though complicated treatment. This type of therapy offers a number of potentially significant advantages compared to traditional radiation therapy. Treatment is better targeted to cancerous cells so that when a tumour is irradiated with neutrons, the damage to normal tissue is respectively less. It is also less demanding for the patient as treatment is only one to two sessions, compared to conventional radiation therapy where patients can be treated up to 30 times. It provides an excellent example of the importance of innovation in the search for a cure to cancer. The recent developments in BNCT in Romania as well as the major drawbacks will be presented. (authors)

  20. In vitro biological models in order to study BNCT

    International Nuclear Information System (INIS)

    Undifferentiated thyroid carcinoma (UTC) lacks an effective treatment. Boron neutron capture therapy (BNCT) is based on the selective uptake of 10B-boronated compounds by some tumours, followed by irradiation with an appropriate neutron beam. The radioactive boron originated (11B) decays releasing 7Li, gamma rays and alpha particles, and these latter will destroy the tumour. In order to explore the possibility of applying BNCT to UTC we have studied the biodistribution of BPA. In vitro studies: the uptake of p-10borophenylalanine (BPA) by the UTC cell line ARO, primary cultures of normal bovine thyroid cells (BT) and human follicular adenoma (FA) thyroid was studied. No difference in BPA uptake was observed between proliferating and quiescent ARO cells. The uptake by quiescent ARO, BT and FA showed that the ARO/BT and ARO/FA ratios were 4 and 5, respectively (p< 0.001). The present experimental results open the possibility of applying BNCT for the treatment of UTC. (author)

  1. Neutron dosimetry in the irradiation program Rheinsberg II

    International Nuclear Information System (INIS)

    Specimens made from reactor pressure vessel steels have been irradiated in the radiation channels of the VVER-2 reactor of NPP Rheinsberg in the frame of a long-termed irradiation programme. The programme has focussed on the enlargement of the data base for evaluation of the radiation embrittlement of the reactor pressure vessel. The irradiation capsules were equipped with neutron activation detectors in order to measure the neutron exposure in the irradiation positions. The report describes the type, the design and the chemical composition of the neutron dosimeters, the arrangement in each experiment, the evaluation procedure after irradiation and summarizes the measured and adjusted neutron fluences for each of the 8 experiments of the irradiation programme Rheinsberg II. The results of the experimental neutron dosimetry confirm the results of the neutron calculation. On this base well-proved data of the neutron exposure are established for the materials irradiated in the irradiation programme Rheinsberg II. (orig.)

  2. Neutron irradiation of beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Gelles, D.S.; Ermi, R.M. [Pacific Northwest National Lab., Richland, WA (United States); Tsai, H. [Argonne National Lab., IL (United States)

    1998-03-01

    Seven subcapsules from the FFTF/MOTA 2B irradiation experiment containing 97 or 100% dense sintered beryllium cylindrical specimens in depleted lithium have been opened and the specimens retrieved for postirradiation examination. Irradiation conditions included 370 C to 1.6 {times} 10{sup 22} n/cm{sup 2}, 425 C to 4.8 {times} 10{sup 22} n/cm{sup 2}, and 550 C to 5.0 {times} 10{sup 22} n/cm{sup 2}. TEM specimens contained in these capsules were also retrieved, but many were broken. Density measurements of the cylindrical specimens showed as much as 1.59% swelling following irradiation at 500 C in 100% dense beryllium. Beryllium at 97% density generally gave slightly lower swelling values.

  3. A suggestion for B-10 imaging during boron neutron capture therapy

    OpenAIRE

    Cortesi, M.

    2007-01-01

    Selective accumulation of B-10 compound in tumour tissue is a fundamental condition for the achievement of BNCT (Boron Neutron Capture Therapy), since the effectiveness of therapy irradiation derives just from neutron capture reaction of B-10. Hence, the determination of the B-10 concentration ratio, between tumour and healthy tissue, and a control of this ratio, during the therapy, are essential to optimise the effectiveness of the BNCT, which it is known to be based on the selective uptake ...

  4. An accelerator-based epithermal photoneutron source for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, D.W.; Mitchell, H.E.; Harker, Y.D.; Yoon, W.Y. [and others

    1995-11-01

    Therapeutically-useful epithermal-neutron beams for BNCT are currently generated by nuclear reactors. Various accelerator-based neutron sources for BNCT have been proposed and some low intensity prototypes of such sources, generally featuring the use of proton beams and beryllium or lithium targets have been constructed. This paper describes an alternate approach to the realization of a clinically useful accelerator-based source of epithermal neutrons for BNCT that reconciles the often conflicting objectives of target cooling, neutron beam intensity, and neutron beam spectral purity via a two stage photoneutron production process.

  5. Carborane-containing metalloporphyrins for BNCT

    International Nuclear Information System (INIS)

    For BNCT of malignant brain tumors, it is crucial that there be relatively high boron concentrations in tumor compared with normal tissues within the neutron-irradiated treatment volume. Fairchild and Bond estimated that major advances in BNCT should be possible if ratios of 10B concentrations in tumor to those in normal tissue (e.g. brain and blood) were at least 5: 1. Given that the only current boron carrier being tested clinically in the U.S., p-boronophenyl-alanine[BPA], yields tumor blood and tumor brain ratios of about 3:1, the criteria for new boronated compounds should be to at least match these ratios and maintain tumor boron concentrations greater than 30 μg B/g. Although previously tested boronated porphyrins have not only matched but surpassed these ratios, it was at a cost of greater toxicity. Chemical and hematological assays of blood analytes; showed marked thrombocytopenia, a decrease to about one-tenth the normal concentration of platelets circulating in the blood, in addition to abnormalities in concentrations of circulating enzymes, that indicated liver toxicity. The physical appearance and behavior of the affected mice were different from those of mice injected with solvent only. Although thrombocytopenia and other toxic effects had disappeared after a few days, previously tested porphyrins would not be safe to infuse into patients for BNCT of potentially hemorrhagic malignant tumors in the brain such as glioblastoma multiforme and metastatic melanoma. We synthesized a different boronated porphyrin, tetracarboranylphenylporphyrin, [TCP] and inserted nickel, copper, or manganese into its coordination center. Biological studies of NiTCP in mice and of CuTCP in rats show that these compounds elicit little or no toxicity when given at potentially therapeutic doses

  6. Carborane-containing metalloporphyrins for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Michiko; Joel, D.D.; Nawrocky, M.M.; Micca, P.L. [and others

    1996-12-31

    For BNCT of malignant brain tumors, it is crucial that there be relatively high boron concentrations in tumor compared with normal tissues within the neutron-irradiated treatment volume. Fairchild and Bond estimated that major advances in BNCT should be possible if ratios of {sup 10}B concentrations in tumor to those in normal tissue (e.g. brain and blood) were at least 5: 1. Given that the only current boron carrier being tested clinically in the U.S., p-boronophenyl-alanine[BPA], yields tumor blood and tumor brain ratios of about 3:1, the criteria for new boronated compounds should be to at least match these ratios and maintain tumor boron concentrations greater than 30 {mu}g B/g. Although previously tested boronated porphyrins have not only matched but surpassed these ratios, it was at a cost of greater toxicity. Chemical and hematological assays of blood analytes; showed marked thrombocytopenia, a decrease to about one-tenth the normal concentration of platelets circulating in the blood, in addition to abnormalities in concentrations of circulating enzymes, that indicated liver toxicity. The physical appearance and behavior of the affected mice were different from those of mice injected with solvent only. Although thrombocytopenia and other toxic effects had disappeared after a few days, previously tested porphyrins would not be safe to infuse into patients for BNCT of potentially hemorrhagic malignant tumors in the brain such as glioblastoma multiforme and metastatic melanoma. We synthesized a different boronated porphyrin, tetracarboranylphenylporphyrin, [TCP] and inserted nickel, copper, or manganese into its coordination center. Biological studies of NiTCP in mice and of CuTCP in rats show that these compounds elicit little or no toxicity when given at potentially therapeutic doses.

  7. Summaries on various researches aiming at the closed head BNCT

    International Nuclear Information System (INIS)

    As in the boron neutron capture therapy (BNCT) flight of alpha particle formed by reaction of neutron and boron is nearly equal to diameter of cancer cell, when a boron compound accumulates selectively to a cancer cell to be radiated onto the cell by enough amount of neutron beam the alpha particles are irradiated onto the cancer cells nearly selectively. Like this, this is a curing means capable of overcoming a problem undecidable by a paradigm of radiation remedy in the 20th Century, a micro dose amount effect supposing to be a paradigm in the 21st Century, the very (biological) dose concentration into cancer cell is a curing method matching to upgrading on rate of cancer control and improvement on post-cure of the patients without increase of subreaction in every tumors. Here were summarized on characteristic comparison of thermal outer-neutron beams in KUR, JRR-4 and the Peten HFR reactors, development of new boron compounds, effect of BNCT on re-oxygenation of the cancer, and induction of mutation by neutron beam. (G.K.)

  8. Tritium release from neutron irradiated beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Scaffidi-Argentina, F.; Werle, H. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reactortechnik

    1998-01-01

    One of the most important open issues related to beryllium for fusion applications refers to the kinetics of the tritium release as a function of neutron fluence and temperature. The EXOTIC-7 as well as the `Beryllium` experiments carried out in the HFR reactor in Petten are considered as the most detailed and significant tests for investigating the beryllium response under neutron irradiation. This paper reviews the present status of beryllium post-irradiation examinations performed at the Forschungszentrum Karlsruhe with samples from the above mentioned irradiation experiments, trying to elucidate the tritium release controlling processes. In agreement with previous studies it has been found that release starts at about 500-550degC and achieves a maximum at about 700-750degC. The observed release at about 500-550degC is probably due to tritium escaping from chemical traps, while the maximum release at about 700-750degC is due to tritium escaping from physical traps. The consequences of a direct contact between beryllium and ceramics during irradiation, causing tritium implanting in a surface layer of beryllium up to a depth of about 40 mm and leading to an additional inventory which is usually several times larger than the neutron-produced one, are also presented and the effects on the tritium release are discussed. (author)

  9. Preliminary computational model for BNCT for breast cancer

    International Nuclear Information System (INIS)

    For the large number of women who are diagnosed with breast cancer every year, the available treatment options are effective, though physically and mentally taxing. This work begins a study of the efficacy of boron neutron capture therapy as an alternative treatment for this type of cancer. Using HER2-specific monoclonal antibodies coupled with a boron rich oligomeric phosphate diester, it may be possible to deliver large amounts of boron-10 to a tumor of the breast, which would allow for selective cell destruction via irradiation with a thermal neutron beam. A preliminary computational model (MCNP) of a deep-seated breast tumor is described as well as the calculated thermal neutron distribution within the tumor resulting from a thermal neutron source similar to those used for BNCT. A linear decrease in flux across the tumor volume is observed due to attenuation within the tissue prior to the tumor. Suggestions for future work are included. (author)

  10. Basic research of boron neutron-capture therapy for treatment of pancreatic cancer. Application of neutron radiography for visualization of boron compound on BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Yanagie, Hironobu [Tokyo Univ. (Japan). Inst. of Medical Science

    1997-02-01

    The cytotoxic effects of locally injected {sup 10}B-immunoliposomes (anti-CEA) on human pancreatic carcinoma xenografts in nude mice were evaluated with thermal neutron irradiation. After thermal neutron irradiation of mice injected with {sup 10}B-immunoliposomes, AsPC-1 tumour growth was suppressed relative to controls. Histopathologically, hyalinization and necrosis were found in {sup 10}B-treated tumours, while tumour tissue injected with saline or saline-containing immunoliposomes showed neither destruction nor necrosis. These results suggest that intratumoral injection of boronated immunoliposomes can increase the retention of {sup 10}B atoms by tumour cells, causing tumour growth suppression in vivo upon thermal neutron irradiation. We prepared boronated PEG-binding bovine serum albumin ({sup 10}B-PEG-BSA). {sup 10}B concentrations in AsPC-1, human pancreatic cancer cells (2 x 10{sup 5} /well) obtained 24 hrs after incubation with {sup 10}B-PEG-BSA was 13.01 {+-} 1.74 ppm. The number of {sup 10}B atoms delivered to the tumor cells was calculated to be 7.83 x 10{sup 11} at 24 hrs after incubation with {sup 10}B-PEG-BSA. These data indicated that the {sup 10}B-PEG-BSA could deliver a sufficient amount of {sup 10}B atoms (more than 10{sup 9} atoms/cell) to the tumor cells to induce cytotoxic effects after incubation upon thermal neutron irradiation. Neutron capture autoradiography by using an Imaging Plate (IP-NCR) was performed on AsPC-1 tumor-bearing mouse that had been given an intratumoral injection of {sup 10}B-PEG BSA or {sup 10}B-cationic liposome. We had demonstrated the {sup 10}B-PEG BSA or {sup 10}B-cationic liposome is taken up by AsPC-1 tumor tissue to a much greater extent than by normal tissues. (J.P.N.)

  11. Basic research of boron neutron-capture therapy for treatment of pancreatic cancer. Application of neutron radiography for visualization of boron compound on BNCT

    International Nuclear Information System (INIS)

    The cytotoxic effects of locally injected 10B-immunoliposomes (anti-CEA) on human pancreatic carcinoma xenografts in nude mice were evaluated with thermal neutron irradiation. After thermal neutron irradiation of mice injected with 10B-immunoliposomes, AsPC-1 tumour growth was suppressed relative to controls. Histopathologically, hyalinization and necrosis were found in 10B-treated tumours, while tumour tissue injected with saline or saline-containing immunoliposomes showed neither destruction nor necrosis. These results suggest that intratumoral injection of boronated immunoliposomes can increase the retention of 10B atoms by tumour cells, causing tumour growth suppression in vivo upon thermal neutron irradiation. We prepared boronated PEG-binding bovine serum albumin (10B-PEG-BSA). 10B concentrations in AsPC-1, human pancreatic cancer cells (2 x 105 /well) obtained 24 hrs after incubation with 10B-PEG-BSA was 13.01 ± 1.74 ppm. The number of 10B atoms delivered to the tumor cells was calculated to be 7.83 x 1011 at 24 hrs after incubation with 10B-PEG-BSA. These data indicated that the 10B-PEG-BSA could deliver a sufficient amount of 10B atoms (more than 109 atoms/cell) to the tumor cells to induce cytotoxic effects after incubation upon thermal neutron irradiation. Neutron capture autoradiography by using an Imaging Plate (IP-NCR) was performed on AsPC-1 tumor-bearing mouse that had been given an intratumoral injection of 10B-PEG BSA or 10B-cationic liposome. We had demonstrated the 10B-PEG BSA or 10B-cationic liposome is taken up by AsPC-1 tumor tissue to a much greater extent than by normal tissues. (J.P.N.)

  12. Neutron Spectrum Measurements from Irradiations at NCERC

    Energy Technology Data Exchange (ETDEWEB)

    Jackman, Kevin Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mosby, Michelle A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bredeweg, Todd Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hutchens, Gregory Joe [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); White, Morgan Curtis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-04-15

    Several irradiations have been conducted on assemblies (COMET/ZEUS and Flattop) at the National Criticality Experiments Research Center (NCERC) located at the Nevada National Security Site (NNSS). Configurations of the assemblies and irradiated materials changed between experiments. Different metallic foils were analyzed using the radioactivation method by gamma-ray spectrometry to understand/characterize the neutron spectra. Results of MCNP calculations are shown. It was concluded that MCNP simulated spectra agree with experimental measurements, with the caveats that some data are limited by statistics at low-energies and some activation foils have low activities.

  13. Vanadium irradiation at ATR - neutronics aspects

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, I.C.; Smith, D.L. [Argonne National Laboratory, Chicago, IL (United States)

    1995-04-01

    Calculations were performed to estimate damage and transmutation rates in vanadium irradiated in the ATR (Advanced Test Reactor) located in Idaho. The main focuses of the study are to evaluate the transmutation of vanadium to chromium and to explore ways to design the irradiation experiment to avoid excessive transmutation. It was found that the A-hole of ATR produces damage rate of {approximately} 0.2%/dpa of vanadium to chromium. A thermal neutron filter can be incorporated into the design to reduce the vanadium-to-chromium transmutation rate to low levels. A filter 1-2 mm thick of gadolinium or hafnium can be used.

  14. Usage of a single TLD-700 for gamma dose measurement in a water phantom irradiated with the epithermal neutron beam at the thor research reactor

    International Nuclear Information System (INIS)

    There are two groups of data that need to be compared in the water phantom irradiated with an epithermal neutron beam for BNCT: (1) the thermal neutron flux, and (2) the gamma dose rate. The comparisons of gamma dose rates between MCNP calculation and TLD measurement are more complex than thermal neutron flux comparison, because of the gamma dose rate can not be taken from TLD-700 readings directly. TLD-700 dose rates contain gamma dose rate, neutron dose rate, and neutron-6Li reaction dose rate. In this article, the responses of TLD-700 to different radiation components were investigated. The results were used for modification to the TLD-700 readings. By this way, the gamma dose rates show a good agreement between the simulation results and experimental data. (author)

  15. Feasibility study on pinhole camera system for online dosimetry in boron neutron capture therapy

    International Nuclear Information System (INIS)

    The feasibility of a pinhole camera system for online dosimetry in boron neutron capture therapy (BNCT) was studied. A prototype system was designed and built. Prompt γ-rays from the 10B(n,α)7Li reaction from a phantom irradiated with neutrons were detected with the prototype system. An image was reconstructed from the experimental data. The reconstructed image showed a good separation of the two borated regions in the phantom. The counting rates and signal-to-noise ratio when using the system in actual BNCT applications are also discussed. - Author-Highlights: • The feasibility of a pinhole camera system for online dosimetry in BNCT was studied. • A prototype pinhole camera system for online dose imaging for BNCT was built. • Prompt γ-rays from a phantom irradiated with neutrons were detected. • The boron-10 reaction rate distribution was reconstructed from the experimental data

  16. Fast-Neutron Irradiation of Large Animals

    International Nuclear Information System (INIS)

    The graphite-moderated, air-cooled reactor BEPO has been modified to provide an area (Sack Hole) of about 14 square feet in which large animals can be irradiated approximately uniformly by fast neutrons produced in a uranium Converter Plate. The mean energy of the fast neutrons is about 0.7 MeV, and the dose rate is 2500 rad/h. A second similar Sack Hole contains a cadmium Converter Plate which gives predominantly gamma-radiation of about 2.5 MeV mean energy, and a dose rate of 1850 rad/h. These two Sack Holes are being used to determine the neutron RBE for acute killing in large approximately man-sized animals. Haematological and biochemical as well as morbid-anatomical observations are being made. The experiment is still in its early stages and preliminary results are presented. (author)

  17. INEL BNCT Research Program annual report 1994

    International Nuclear Information System (INIS)

    This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1994. Contributions from the principal investigators about their individual projects are included, specifically, chemistry (pituitary tumor studies, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, ICP-AES analysis of biological samples), physics (treatment planning software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (small and large animal models tissue studies and efficacy studies). Information on the potential toxicity of BSH and BPA is presented and results of 21 spontaneous tumor bearing dogs that have been treated with BNCT at Brookhaven National Laboratory (BNL) are discussed. Several boron carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors is presented. Highlights from the First International Workshop on Accelerator-Based Neutron Sources for BNCT are included

  18. Biological Tests for Boron Neutron Capture Therapy Research at the TRIGA Mark II Reactor in Pavia

    International Nuclear Information System (INIS)

    The thermal column of the TRIGA Mark II reactor of the Pavia University is used as an irradiation facility to perform biological tests and irradiations of living systems for Boron Neutron Capture Therapy (BNCT) research. The suitability of the facility has been ensured by studying the neutron flux and the photon background in the irradiation chamber inside the thermal column. This characterization has been realized both by flux and dose measurements as well as by Monte Carlo simulations. The routine irradiations concern in vitro cells cultures and different tumor animal models to test the efficacy of the BNCT treatment. Some results about these experiments will be described. (author)

  19. Biological Tests for Boron Neutron Capture Therapy Research at the TRIGA Mark II Reactor in Pavia

    Energy Technology Data Exchange (ETDEWEB)

    Protti, N.; Ballarini, F.; Bortolussi, S.; De Bari, A.; Stella, S.; Altieri, S. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); Nuclear Physics National Institute (INFN), Pavia (Italy); Bruschi, P. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); Bakeine, J.G.; Cansolino, L.; Clerici, A.M. [Laboratory of Experimental Surgery, Department of Surgery, University of Pavia, Pavia (Italy)

    2011-07-01

    The thermal column of the TRIGA Mark II reactor of the Pavia University is used as an irradiation facility to perform biological tests and irradiations of living systems for Boron Neutron Capture Therapy (BNCT) research. The suitability of the facility has been ensured by studying the neutron flux and the photon background in the irradiation chamber inside the thermal column. This characterization has been realized both by flux and dose measurements as well as by Monte Carlo simulations. The routine irradiations concern in vitro cells cultures and different tumor animal models to test the efficacy of the BNCT treatment. Some results about these experiments will be described. (author)

  20. Optimization of intraoperative (IO) BNCT: pre-irradiation surgical technique and 2-D dosimetry in surgical field

    International Nuclear Information System (INIS)

    In IOBNCT, pre-irradiation surgery and clinical dosimetry procedures, and the patient's head position toward the beam port are crucial in optimum beam delivery to the target area. From Oct. 1999, 5 patients with malignant glioma were treated with IOBNCT at JRR-4. 2 fronto-temporal craniotomies and 1 occipital craniotomy were performed. 2 temporal lesions were explored with fronto-temporo-zygomatic approach (FTZ). In irradiation with occipital craniotomy, superior sagittal sinus (SSS) lied adjacent to post-surgical cavity that unwillingly enhanced the dose at the SSS by void effect. For FTZ, we aimed to avoid insufficient dose delivery to the lower frontal and anterior temporal regions that were caused by relatively increased core-target distance due to reflected skin flap and LiF thermoplastic collimator. Two-dimensional thermal neutron flux distributions in post-surgical field were influenced by head position, void effect, and the shape of LiF thermoplastic collimator. A simple simulation method for IOBNCT has been developed which improved the pre-irradiation treatment planning. However, more sophisticated dose planning system combined with patient setting system should be developed. (author)

  1. Effects of neutron and continuous gamma irradiation of rats

    International Nuclear Information System (INIS)

    The effect of single neutron irradiation (2 Gy) alone and combined with continuous gamma irradiation (6 Gy accumulated during 10.5 days) was studied on the survival of rats and on nucleic acids both in the lymphoid organs and testes. After neutron irradiation alone the most profound changes in lymphoid organs and testes were found on the third and within the days 28-60, respectively. Regeneration has been undergone at a relatively fast rate. Continuous irradiation subsequent to neutron irradiation deepened only slightly the extent of the initial changes. The effect of combined irradiation manifested mainly at later times in marked slowing down of regeneration. (author)

  2. Medical setup of intraoperative BNCT at JRR-4

    International Nuclear Information System (INIS)

    Since October 1999, we have been performing clinical trials of intraoperative boron neutron capture therapy (IOBNCT) using a mixed thermal-epithermal beam at the Japan Research Reactor No. 4 (JRR-4). For immediate pre-BNCT care, including administration of a boron compound as well as post-BNCT care, a collaborating neurosurgical department of the University of Tsukuba was prepared in the vicinity of JRR-4. Following craniotomy in the treatment room, anesthetized patients were transported into the irradiation room for BNCT. The boron concentration in tissue was measured by the PGA and ICP-AES methods. The long-term follow-up was done at the University of Tsukuba Hospital. IOBNCT is a complex clinical procedure, which requires sophisticated operating team and co-medical staffs and also cooperation with physicist team. IOBNCT is a complex clinical procedure requiring a high level of cooperation among the operating team, co-medical staff, and physicists. For the safe and successful performance of IOBNCT, we have made the program including critical pathway and prepared various equipments for IOBNCT. To ensure the safe and successful performance of IOBNCT, we developed a critical pathway for use during the procedure, and prepared various apparatus for IOBNCT. (author)

  3. Clinical results of BNCT for malignant brain tumors in children

    International Nuclear Information System (INIS)

    It is very difficult to treat the patients with malignant brain tumor in children, especially under 3 years, because the conventional irradiation cannot be applied due to the damage of normal brain tissue. However, boron neutron capture therapy (BNCT) has tumor selectivity such that it can make damage only in tumor cells. We evaluated the clinical results and courses in patients with malignant glioma under 15 years. Among 183 patients with brain tumors treated by our group using BSH-based intra-operative BNCT, 23 patients were under 15 years. They included 4 patients under 3 years. There were 3 glioblastomas (GBM), 6 anaplastic astrocytomas(AAS), 7 primitive neuroectodermal tumors (PNET), 6 pontine gliomas and 1 anaplastic ependymoma. All GBM and PNET patients died due to CSF and/or CNS dissemination without local tumor regrowth. All pontine glioma patients died due to regrowth of the tumor. Four of 6 anaplastic astrocytoma and 1 anaplastic ependymoma patients alive without tumor recurrence. BNCT can be applied to malignant brain tumors in children, especially under 3 years instead of conventional radiation. Although it can achieve the local control in the primary site, it cannot prevent CSF dissemination in patients with glioblastoma.

  4. Clinical results of BNCT for malignant brain tumors in children

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Yoshinobu [Department of Neurosurgery, Kagawa National Children' s Hospital, Kagawa 765-8501 (Japan)], E-mail: ynakagawa0517@yahoo.co.jp; Kageji, Teruyoshi; Mizobuchi, Yoshifumi [Department of Neurosurgery, University of Tokushima, Tokushima 770-8503 (Japan); Kumada, Hiroaki [Department of Research Reactor, Japan Atomic Energy Research Institute, Ibaragi 319-1195 (Japan); Nakagawa, Yoshiaki [Department of Medical Informatics, Post Graduated School, Kyoto University, Kyoto (Japan)

    2009-07-15

    It is very difficult to treat the patients with malignant brain tumor in children, especially under 3 years, because the conventional irradiation cannot be applied due to the damage of normal brain tissue. However, boron neutron capture therapy (BNCT) has tumor selectivity such that it can make damage only in tumor cells. We evaluated the clinical results and courses in patients with malignant glioma under 15 years. Among 183 patients with brain tumors treated by our group using BSH-based intra-operative BNCT, 23 patients were under 15 years. They included 4 patients under 3 years. There were 3 glioblastomas (GBM), 6 anaplastic astrocytomas(AAS), 7 primitive neuroectodermal tumors (PNET), 6 pontine gliomas and 1 anaplastic ependymoma. All GBM and PNET patients died due to CSF and/or CNS dissemination without local tumor regrowth. All pontine glioma patients died due to regrowth of the tumor. Four of 6 anaplastic astrocytoma and 1 anaplastic ependymoma patients alive without tumor recurrence. BNCT can be applied to malignant brain tumors in children, especially under 3 years instead of conventional radiation. Although it can achieve the local control in the primary site, it cannot prevent CSF dissemination in patients with glioblastoma.

  5. Neutron flux profile determination for an in-pool animal irradiation facility

    Energy Technology Data Exchange (ETDEWEB)

    Bose, S.R.; Mulder, R.U.; Rydin, R.A. [Univ. of Virginia, Charlottesville, VA (United States)] [and others

    1997-12-01

    The University of Virginia 2-MW pool-type nuclear research reactor (UVAR) is used actively for neutron activation analysis, neutron radiography, gemstone coloration, radioisotope production, neutron transmutation doping, and, more recently, medical research. Neutron beams for neutron radiography are extracted from the southeast and southwest edges of the core. While excellent for radiography, the flux intensity of these beams is much too low to permit their use in medical research. Therefore, planning has begun for the installation of a filtered epithermal neutron beamport with flux suitable for boron neutron capture therapy (BNCT) of human cancers. The design of this beamport has been reported previously.

  6. Neutron flux profile determination for an in-pool animal irradiation facility

    International Nuclear Information System (INIS)

    The University of Virginia 2-MW pool-type nuclear research reactor (UVAR) is used actively for neutron activation analysis, neutron radiography, gemstone coloration, radioisotope production, neutron transmutation doping, and, more recently, medical research. Neutron beams for neutron radiography are extracted from the southeast and southwest edges of the core. While excellent for radiography, the flux intensity of these beams is much too low to permit their use in medical research. Therefore, planning has begun for the installation of a filtered epithermal neutron beamport with flux suitable for boron neutron capture therapy (BNCT) of human cancers. The design of this beamport has been reported previously

  7. THERMAL NEUTRON INTENSITIES IN SOILS IRRADIATED BY FAST NEUTRONS FROM POINT SOURCES. (R825549C054)

    Science.gov (United States)

    Thermal-neutron fluences in soil are reported for selected fast-neutron sources, selected soil types, and selected irradiation geometries. Sources include 14 MeV neutrons from accelerators, neutrons from spontaneously fissioning 252Cf, and neutrons produced from alp...

  8. Beam shaping assembly optimization for 7Li(p,n)7Be accelerator based BNCT

    International Nuclear Information System (INIS)

    Within the framework of accelerator-based BNCT, a project to develop a folded Tandem-ElectroStatic-Quadrupole accelerator is under way at the Atomic Energy Commission of Argentina. The proposed accelerator is conceived to deliver a proton beam of 30 mA at about 2.5 MeV. In this work we explore a Beam Shaping Assembly (BSA) design based on the 7Li(p,n)7Be neutron production reaction to obtain neutron beams to treat deep seated tumors. - Highlights: • A Beam Shaping Assembly for accelerator based BNCT has been designed. • A conical port for easy patient positioning and the cooling system are included. • Several configurations can deliver tumor doses greater than 55 RBEGy. • Good tumor doses can be obtained in less than 60 min of irradiation time

  9. Neutron capture therapy (NCT) and in-hospital neutron irradiator (IHNI) a new technology on binary targeting radiation therapy of cancer

    International Nuclear Information System (INIS)

    BNCT is finally becoming 'a new option against cancer'. The difficulties for its development progress of that firstly is to improve the performance of boron compounds,secondly, it is the requirements of quantification and accuracy upon radiation dosimetry evaluation in clinical trials. Furthermore, that is long anticipation on hospital base neutron sources. It includes dedicated new NCT reactor, accelerator based neutron sources, and isotope source facilities. In addition to reactors, so far, the technology of other types of sources for clinical trials is not yet completely proven. The In-Hospital Neutron Irradiator specially designed for NCT, based on the MNSR successfully developed by China, can be installed inside or near the hospital and operated directly by doctors. The Irradiator has two neutron beams for respective treatment of the shallow and deep tumors. It is expected to initiate operation in the end of this year. It would provide a safe, low cost, and effective treatment tool for the NCT routine application in near future. (authors)

  10. Experimental Studies of Boronophenylalanine (10BPA) Biodistribution for the Individual Application of Boron Neutron Capture Therapy (BNCT) for Malignant Melanoma Treatment

    International Nuclear Information System (INIS)

    Purpose: Patients with the same histopathologic diagnosis of cutaneous melanoma treated with identical protocols of boron neutron capture therapy (BNCT) have shown different clinical outcomes. The objective of the present studies was to evaluate the biodistribution of boronophenilalanina (10BPA) for the potential application of BNCT for the treatment of melanoma on an individual basis. Methods and Materials: The boronophenilalanine (BPA) uptake was evaluated in 3 human melanoma cell lines: MEL-J, A375, and M8. NIH nude mice were implanted with 4 106 MEL-J cells, and biodistribution studies of BPA (350 mg/kg intraperitoneally) were performed. Static infrared imaging using a specially modified infrared camera adapted to measure the body infrared radiance of small animals was used. Proliferation marker, Ki-67, and endothelial marker, CD31, were analyzed in tumor samples. Results: The in vitro studies demonstrated different patterns of BPA uptake for each analyzed cell line (P<.001 for MEL-J and A375 vs M8 cells). The in vivo studies showed a maximum average boron concentration of 25.9 ± 2.6 μg/g in tumor, with individual values ranging between 11.7 and 52.0 μg/g of 10B 2 hours after the injection of BPA. Tumor temperature always decreased as the tumors increased in size, with values ranging between 37°C and 23°C. A significant correlation between tumor temperature and tumor-to-blood boron concentration ratio was found (R2 = 0.7, rational function fit). The immunohistochemical studies revealed, in tumors with extensive areas of viability, a high number of positive cells for Ki-67, blood vessels of large diameter evidenced by the marker CD31, and a direct logistic correlation between proliferative status and boron concentration difference between tumor and blood (R2 = 0.81, logistic function fit). Conclusion: We propose that these methods could be suitable for designing new screening protocols applied before melanoma BNCT treatment for each individual

  11. Experimental Studies of Boronophenylalanine ({sup 10}BPA) Biodistribution for the Individual Application of Boron Neutron Capture Therapy (BNCT) for Malignant Melanoma Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Carpano, Marina; Perona, Marina; Rodriguez, Carla [Department of Radiobiology, National Atomic Energy Commission, San Martín (Argentina); Nievas, Susana; Olivera, Maria; Santa Cruz, Gustavo A. [Department of Boron Neutron Capture Therapy, National Atomic Energy Commission, San Martín (Argentina); Brandizzi, Daniel; Cabrini, Romulo [Department of Radiobiology, National Atomic Energy Commission, San Martín (Argentina); School of Dentistry, University of Buenos Aires, Buenos Aires (Argentina); Pisarev, Mario [Department of Radiobiology, National Atomic Energy Commission, San Martín (Argentina); National Research Council of Argentina, Buenos Aires (Argentina); Department of Human Biochemistry, School of Medicine, University of Buenos Aires, Buenos Aires (Argentina); Juvenal, Guillermo Juan [Department of Radiobiology, National Atomic Energy Commission, San Martín (Argentina); National Research Council of Argentina, Buenos Aires (Argentina); Dagrosa, Maria Alejandra, E-mail: dagrosa@cnea.gov.ar [Department of Radiobiology, National Atomic Energy Commission, San Martín (Argentina); National Research Council of Argentina, Buenos Aires (Argentina)

    2015-10-01

    Purpose: Patients with the same histopathologic diagnosis of cutaneous melanoma treated with identical protocols of boron neutron capture therapy (BNCT) have shown different clinical outcomes. The objective of the present studies was to evaluate the biodistribution of boronophenilalanina ({sup 10}BPA) for the potential application of BNCT for the treatment of melanoma on an individual basis. Methods and Materials: The boronophenilalanine (BPA) uptake was evaluated in 3 human melanoma cell lines: MEL-J, A375, and M8. NIH nude mice were implanted with 4 10{sup 6} MEL-J cells, and biodistribution studies of BPA (350 mg/kg intraperitoneally) were performed. Static infrared imaging using a specially modified infrared camera adapted to measure the body infrared radiance of small animals was used. Proliferation marker, Ki-67, and endothelial marker, CD31, were analyzed in tumor samples. Results: The in vitro studies demonstrated different patterns of BPA uptake for each analyzed cell line (P<.001 for MEL-J and A375 vs M8 cells). The in vivo studies showed a maximum average boron concentration of 25.9 ± 2.6 μg/g in tumor, with individual values ranging between 11.7 and 52.0 μg/g of {sup 10}B 2 hours after the injection of BPA. Tumor temperature always decreased as the tumors increased in size, with values ranging between 37°C and 23°C. A significant correlation between tumor temperature and tumor-to-blood boron concentration ratio was found (R{sup 2} = 0.7, rational function fit). The immunohistochemical studies revealed, in tumors with extensive areas of viability, a high number of positive cells for Ki-67, blood vessels of large diameter evidenced by the marker CD31, and a direct logistic correlation between proliferative status and boron concentration difference between tumor and blood (R{sup 2} = 0.81, logistic function fit). Conclusion: We propose that these methods could be suitable for designing new screening protocols applied before melanoma BNCT

  12. Radiation damage of pixelated photon detector by neutron irradiation

    Science.gov (United States)

    Nakamura, Isamu

    2009-10-01

    Radiation Damage of Pixelated Photon Detector by neutron irradiation is reported. MPPC, one of PPD or Geiger-mode APD, developed by Hamamatsu Photonics, is planned to be used in many high energy physics experiments. In such experiments radiation damage is a serious issue. A series of neutron irradiation tests is performed at the Reactor YAYOI of the University of Tokyo. MPPCs were irradiated at the reactor up to 1012 neutron/cm2. In this paper, the effect of neutron irradiation on the basic characteristics of PPD including gain, noise rate, photon detection efficiency is presented.

  13. Basic requirements and parameter optimization for boron neutron capture therapy of extracorporeal irradiated and auto-transplanted organs

    International Nuclear Information System (INIS)

    Background: In 2001 and 2003, at the University of Pavia, Italy, boron neutron capture therapy (BNCT) has been successfully used in the treatment of hepatic colorectal metastases (). The treatment procedure (TAOrMINA protocol) is characterised by the auto-transplantation and extracorporeal irradiation of the liver using a thermal neutron beam. Methods: The clinical use of this approach requires well founded data and an optimized irradiation facility. In order to start with this work and to decide upon its feasibility at the research reactor TRIGA Mainz, basic data and requirements have been considered (). Computer calculations using the ATTILA () and MCNP () codes have been performed, including data from conventional radiation therapy, from the TAOrMINA approach, resulting in reasonable estimations. Results: Basic data and requirements and optimal parameters have been worked out, especially for use at an optimized TRIGA irradiation facility (). Advantages of the extracorporeal irradiation with auto-transplantation and the potential of an optimized irradiation facility could be identified. Within the requirements, turning the explanted organ over by 180° appears preferable to a whole side source, similar to a permanent rotation of the organ. Conclusions: The design study and the parameter optimization confirm the potential of this approach to treat metastases in explanted organs. The results do not represent actual treatment data but a first estimation. Although all specific values refer to the TRIGA Mainz, they may act as a useful guide for other types of neutron sources. The recommended modifications () show the suitability of TRIGA reactors as a radiation source for BNCT of extracorporeal irradiated and auto-transplanted organs. - Highlights: ► The approach to treat metastases in explanted organs allows for more specific optimization. ► A modified TRIGA as a neutron source can achieve promising results in short irradiation times. ► Turning the organ in the

  14. Antiproliferative effect and apoptosis induction in melanoma treatment by boron neutron capture therapy (BCNT)

    International Nuclear Information System (INIS)

    Full text: Introduction: Boron neutron capture therapy (BNCT) is an experimental radiotherapy where a compound having 10B is administered to cancer patients and is accumulated in tumor tissues. Thus, the tumor is irradiated with thermal neutrons, 10B absorbs and destroys them, producing alpha radiation. Boronophenylalanine (BPA) is the agent responsible for delivering boron to the tumor tissue. After BPA administration, BNCT is used as a localized radiotherapy for many tumors treatment, mainly melanoma, which has a high mortality rate among all types of tumors. The aim of this study was to evaluate in vitro antiproliferative and antitumor effects of BNCT application in human melanoma treatment. Materials and Methods: MEWO cells (human melanoma) were cultured and treated with different concentrations of BPA (8.36 to 0.52 mg/ml). After 90 minutes, they were irradiated with thermal neutron flux up to a dose of 8.4 Gy. The parameters analyzed were free radical production, cell cycle progression, cell death signaling pathways, cycling D1, caspase-3 and extracellular matrix synthesis produced, beyond the mitochondrial electric potential analysis. Results: After BNCT treatment, MEWO cells showed an amount of free radical increase about 10 times. Still, there was a significant decrease of cyclin D1, G0/G1 proliferation, synthesis and G2/M cell cycle phases. BNCT induced a mitochondrial electrical potential decrease, as well as fibrillar proteins of extracellular matrix. BNCT had a significant number of dead cell increase, mainly by necrosis. However, BNCT induced phosphorylated caspase 3 increase. Discussion/Conclusion: BNCT induced cell death increase by necrosis, mitochondrial electric potential decrease and free radical production increase. BNCT is cytotoxic to melanoma cells. Besides necrosis, phosphorylated caspase 3 increase was observed, accompanied by a proliferative response decrease regulated by the G1/S checkpoint and matrix extracellular synthesis reduction

  15. Antiproliferative effect and apoptosis induction in melanoma treatment by boron neutron capture therapy (BCNT)

    Energy Technology Data Exchange (ETDEWEB)

    Faiao-Flores, Fernanda; Coelho, Paulo; Arruda-Neto, Joao; Maria, Durvanei [University of Sao Paulo (USP), SP (Brazil)

    2011-07-01

    Full text: Introduction: Boron neutron capture therapy (BNCT) is an experimental radiotherapy where a compound having {sup 10}B is administered to cancer patients and is accumulated in tumor tissues. Thus, the tumor is irradiated with thermal neutrons, {sup 10}B absorbs and destroys them, producing alpha radiation. Boronophenylalanine (BPA) is the agent responsible for delivering boron to the tumor tissue. After BPA administration, BNCT is used as a localized radiotherapy for many tumors treatment, mainly melanoma, which has a high mortality rate among all types of tumors. The aim of this study was to evaluate in vitro antiproliferative and antitumor effects of BNCT application in human melanoma treatment. Materials and Methods: MEWO cells (human melanoma) were cultured and treated with different concentrations of BPA (8.36 to 0.52 mg/ml). After 90 minutes, they were irradiated with thermal neutron flux up to a dose of 8.4 Gy. The parameters analyzed were free radical production, cell cycle progression, cell death signaling pathways, cycling D1, caspase-3 and extracellular matrix synthesis produced, beyond the mitochondrial electric potential analysis. Results: After BNCT treatment, MEWO cells showed an amount of free radical increase about 10 times. Still, there was a significant decrease of cyclin D1, G0/G1 proliferation, synthesis and G2/M cell cycle phases. BNCT induced a mitochondrial electrical potential decrease, as well as fibrillar proteins of extracellular matrix. BNCT had a significant number of dead cell increase, mainly by necrosis. However, BNCT induced phosphorylated caspase 3 increase. Discussion/Conclusion: BNCT induced cell death increase by necrosis, mitochondrial electric potential decrease and free radical production increase. BNCT is cytotoxic to melanoma cells. Besides necrosis, phosphorylated caspase 3 increase was observed, accompanied by a proliferative response decrease regulated by the G1/S checkpoint and matrix extracellular synthesis

  16. TEM study of neutron-irradiated iron

    Energy Technology Data Exchange (ETDEWEB)

    Horton, L.L.; Bentley, J.; Farrell, K.

    1981-01-01

    Results of a transmission electron microscopy study of the defect structure in iron neutron-irradiated to low fluences (less than or equal to 1 dpa) at temperatures of 455 to 1013/sup 0/K are presented. The dislocation microstructures coarsen with increasing irradiation temperature from decorated dislocations, through clusters of dislocation loops, to near-edge, interstitial dislocation loops with b = a<100>, and network segments. Significant cavity formation occurred only at 548 to 723/sup 0/K, with homogeneous distributions found only at 623 and 673/sup 0/K. The maximum swelling of 0.07% occurred at 673/sup 0/K. Large cavities had a truncated octahedral shape with (111) facets and (100) truncations. Damage halos were observed around boron-containing precipitates. The effects of interstitial impurities on microstructural development and the differences in the observed microstructures compared to those in refractory bcc metals are discussed. 8 figures, 6 tables.

  17. Research needs for neutron capture therapy

    International Nuclear Information System (INIS)

    Key issues and questions addressed by the workshop related to optimization of Boron Neutron Capture Therapy (BNCT), in general, and to the possibility of success of the present BNCT trials at Brookhaven National Laboratory (BNL) and Massachusetts Institute of Technology (MIT), in particular. Both trials use nuclear fission reactors as neutron sources for BNCT of glioblastoma multiforme (BNL) and of deep seated melanoma (MIT). Presentations and discussions focussed on optimal boron-labeled compounds, mainly for brain tumors such as glioblastoma multiforme, and the best mode of compound delivery to the tumor. Also, optimizing neutron irradiation with dose delivery to the tumor cells and the issues of dosimetry of BNCT especially in the brain were discussed. Planning of treatment and of follow-up of patients, coordination of BNCT at various treatment sites, and the potential of delivering BNCT to various types of cancer with an appropriately tailored protocol were additional issues. The need for multicentric interdisciplinary cooperation among the different medical specialties was highlighted

  18. Research needs for neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    Key issues and questions addressed by the workshop related to optimization of Boron Neutron Capture Therapy (BNCT), in general, and to the possibility of success of the present BNCT trials at Brookhaven National Laboratory (BNL) and Massachusetts Institute of Technology (MIT), in particular. Both trials use nuclear fission reactors as neutron sources for BNCT of glioblastoma multiforme (BNL) and of deep seated melanoma (MIT). Presentations and discussions focussed on optimal boron-labeled compounds, mainly for brain tumors such as glioblastoma multiforme, and the best mode of compound delivery to the tumor. Also, optimizing neutron irradiation with dose delivery to the tumor cells and the issues of dosimetry of BNCT especially in the brain were discussed. Planning of treatment and of follow-up of patients, coordination of BNCT at various treatment sites, and the potential of delivering BNCT to various types of cancer with an appropriately tailored protocol were additional issues. The need for multicentric interdisciplinary cooperation among the different medical specialties was highlighted.

  19. Neutron Flux Characterization of Irradiation Holes for Irradiation Test at HANARO

    OpenAIRE

    Yang Seong Woo; Cho Man Soon; Choo Kee Nam; Park Sang Jun

    2016-01-01

    The High flux Advanced Neutron Application ReactOr (HANARO) is a unique research reactor in the Republic of Korea, and has been used for irradiation testing since 1998. To conduct irradiation tests for nuclear materials, the irradiation holes of CT and OR5 have been used due to a high fast-neutron flux. Because the neutron flux must be accurately calculated to evaluate the neutron fluence of irradiated material, it was conducted using MCNP. The neutron flux was measured using fluence monitor ...

  20. BNCT Technology Development on HANARO Reactor

    International Nuclear Information System (INIS)

    So as to establish the biological effects of BNCT in the HANARO Reactor, biological damages in cells and animals with treatment of boron/neutron were investigated. And 124I-BPA animal PET image, analysis technology of the boron contents in the mouse tissues by ICP-AES was established. A Standard clinical protocol, a toxicity evaluation report and an efficacy investigation report of BNCT has been developed. Based on these data, the primary permission of clinical application was acquired through IRB of our hospital. Three cases of pre-clinical experiment for boron distribution and two cases of medium-sized animal simulation experiment using cat with verifying for 2 months after BNCT was performed and so the clinical demonstration with a patient was prepared. Also neutron flux, fast neutron flux and gamma ray dose of BNCT facility were calculated and these data will be utilized good informations for clinical trials and further BNCT research. For the new synthesis of a boron compound, o-carboranyl ethylamine, o-carboranylenepiperidine, o-carboranyl-THIQ and o-carboranyl-s-triazine derivatives were synthesized. Among them, boron uptake in the cancer cell of the triazine derivative was about 25 times than that of BPA and so these three synthesized methods of new boron compounds were patented

  1. BNCT Technology Development on HANARO Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Ki Jung; Park, Kyung Bae; Whang, Seung Ryul; Kim, Myong Seop

    2007-06-15

    So as to establish the biological effects of BNCT in the HANARO Reactor, biological damages in cells and animals with treatment of boron/neutron were investigated. And 124I-BPA animal PET image, analysis technology of the boron contents in the mouse tissues by ICP-AES was established. A Standard clinical protocol, a toxicity evaluation report and an efficacy investigation report of BNCT has been developed. Based on these data, the primary permission of clinical application was acquired through IRB of our hospital. Three cases of pre-clinical experiment for boron distribution and two cases of medium-sized animal simulation experiment using cat with verifying for 2 months after BNCT was performed and so the clinical demonstration with a patient was prepared. Also neutron flux, fast neutron flux and gamma ray dose of BNCT facility were calculated and these data will be utilized good informations for clinical trials and further BNCT research. For the new synthesis of a boron compound, o-carboranyl ethylamine, o-carboranylenepiperidine, o-carboranyl-THIQ and o-carboranyl-s-triazine derivatives were synthesized. Among them, boron uptake in the cancer cell of the triazine derivative was about 25 times than that of BPA and so these three synthesized methods of new boron compounds were patented.

  2. Nuclear Physics meets Medicine and Biology: Boron Neutron Capture Therapy

    CERN Document Server

    F. Ballarini, F; S. Bortolussi, S; P. Bruschi, P; A.M. Clerici, A M; A. De Bari, A; P. Dionigi, P; C. Ferrari, C; M.A. Gadan, M A; N. Protti, N; S. Stella, S; C. Zonta, C; A. Zonta, A; S. Altieri, S

    2010-01-01

    BNCT is a tumour treatment based on thermal-neutron irradiation of tissues enriched with 10B, which according to the 10B(n, )7Li reaction produces particles with high Linear Energy Transfer and short range. Since this treatment can deliver a therapeutic tumour dose sparing normal tissues, BNCT represents an alternative for diffuse tumours and metastases, which show poor response to surgery and photontherapy. In 2001 and 2003, in Pavia BNCT was applied to an isolated liver, which was infused with boron, explanted, irradiated and re-implanted. A new project was then initiated for lung tumours, developing a protocol for Boron concentration measurements and performing organ-dose Monte Carlo calculations; in parallel, radiobiology studies are ongoing to characterize the BNCT effects down to cellular level. After a brief introduction, herein we will present the main activities ongoing in Pavia including the radiobiological ones, which are under investigation not only experimentally but also theoretically, basing on...

  3. Antitumor potential induction and free radicals production in melanoma cells by Boron Neutron Capture Therapy

    International Nuclear Information System (INIS)

    Antiproliferative and oxidative damage effects occurring in Boron Neutron Capture Therapy (BNCT) in normal fibroblasts and melanoma cell lines were analyzed. Melanoma cells and normal fibroblasts were treated with different concentrations of Boronophenylalanine and irradiated with thermal neutron flux. The cellular viability and the oxidative stress were determined. BNCT induced free radicals production and proliferative potential inhibition in melanoma cells. Therefore, this therapeutic technique could be considered efficient to inhibit growth of melanoma with minimal effects on normal tissues. - Highlights: ► Boron Neutron Capture Therapy (BNCT) induces melanoma cell death. ► BNCT stimulates free radicals production and proliferative inhibition in melanoma cells. ► It produces tumor membrane degeneration and destruction with apoptotic bodies formation. ► This therapy damages tumor cells selectively, with minimum effects on normal adjacent tissue.

  4. Antitumor potential induction and free radicals production in melanoma cells by Boron Neutron Capture Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Faiao-Flores, F. [Biochemical and Biophysical Laboratory, Butantan Institute, 1500 Vital Brasil Avenue, Sao Paulo (Brazil)] [Faculty of Medicine, University of Sao Paulo, 455 Doutor Arnaldo Avenue, Sao Paulo (Brazil); Coelho, P.R.P.; Muniz, R.O.R.; Souza, G.S. [Institute for Nuclear and Energy Research, 2242 Lineu Prestes Avenue, Sao Paulo (Brazil); Arruda-Neto, J. [Physics Institute, University of Sao Paulo, 187 Matao Street, Sao Paulo (Brazil)] [FESP, Sao Paulo Engineering School, 5520 Nove de Julho Avenue, Sao Paulo (Brazil); Maria, Durvanei A., E-mail: durvaneiaugusto@yahoo.com.br [Biochemical and Biophysical Laboratory, Butantan Institute, 1500 Vital Brasil Avenue, Sao Paulo (Brazil)

    2011-12-15

    Antiproliferative and oxidative damage effects occurring in Boron Neutron Capture Therapy (BNCT) in normal fibroblasts and melanoma cell lines were analyzed. Melanoma cells and normal fibroblasts were treated with different concentrations of Boronophenylalanine and irradiated with thermal neutron flux. The cellular viability and the oxidative stress were determined. BNCT induced free radicals production and proliferative potential inhibition in melanoma cells. Therefore, this therapeutic technique could be considered efficient to inhibit growth of melanoma with minimal effects on normal tissues. - Highlights: Black-Right-Pointing-Pointer Boron Neutron Capture Therapy (BNCT) induces melanoma cell death. Black-Right-Pointing-Pointer BNCT stimulates free radicals production and proliferative inhibition in melanoma cells. Black-Right-Pointing-Pointer It produces tumor membrane degeneration and destruction with apoptotic bodies formation. Black-Right-Pointing-Pointer This therapy damages tumor cells selectively, with minimum effects on normal adjacent tissue.

  5. Boron neutron capture therapy of ocular melanoma and intracranial glioma using p-boronophenylalanine

    International Nuclear Information System (INIS)

    During conventional radiotherapy, the dose that can be delivered to the tumor is limited by the tolerance of the surrounding normal tissue within the treatment volume. Boron Neutron Capture Therapy (BNCT) represents a promising modality for selective tumor irradiation. The key to effective BNCT is selective localization of 10B in the tumor. We have shown that the synthetic amino acid p-boronophenylalanine (BPA) will selectively deliver boron to melanomas and other tumors such as gliosarcomas and mammary carcinomas. Systemically delivered BPA may have general utility as a boron delivery agent for BNCT. In this paper, BNCT with BPA is used in treatment of experimentally induced gliosarcoma in rats and nonpigmented melanoma in rabbits. The tissue distribution of boron is described, as is response to the BNCT. 6 refs., 4 figs., 1 tab

  6. Design and testing of a rotating, cooled device for extra-corporate treatment of liver cancer by BNCT in the epithermal neutron beam at the HFR Petten

    International Nuclear Information System (INIS)

    As part of the joint project on extra-corporal treatment of liver cancer by BNCT between JRC Petten and the University Hospital Essen, a facility has been designed and built to contain the liver during its irradiation treatment at the HFR Petten. The design consists of a rotating spheroid shaped PMMA holder, manufactured to open at the equator and closed by screwing together, surrounded by PMMA and graphite blocks. A validation exercise has been performed regarding both the nuclear conditions and the physical conditions. For the former, activation foil sets of Au, Cu and Mn, were irradiated at positions inside the liver holder filled with water, whilst a second measurement campaign has been performed using gel dosimetry. For the physical test, it is required to operate (rotate) the facility for up to 4 hours and to maintain the liver at approximately 4degC. The latter test was performed using 'cold gun sprays' that inject cold air near the liver holder. Both the nuclear and physical validation tests were performed successfully. (author)

  7. Comparison of intracerebral delivery of carboplatin and photon irradiation with an optimized regimen for boron neutron capture therapy of the F98 rat glioma

    Energy Technology Data Exchange (ETDEWEB)

    Barth, Rolf F., E-mail: rolf.barth@osumc.edu [Department of Pathology, Ohio State University, 165 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210 (United States); Yang Weilian; Huo Tianyao [Department of Pathology, Ohio State University, 165 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210 (United States); Riley, Kent J.; Binns, Peter J. [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Grecula, John C., E-mail: john.grecula@osumc.edu [James Cancer Hospital and Solove Research Institute, Department of Radiation Oncology, Ohio State University, Columbus, OH, 43210 (United States); Gupta, Nilendu, E-mail: nilendu.gupta@osumc.edu [James Cancer Hospital and Solove Research Institute, Department of Radiation Oncology, Ohio State University, Columbus, OH, 43210 (United States); Rousseau, Julia, E-mail: julia.rousseau@yahoo.fr [INSERM, U836, Institute of Neurosciences, Grenoble (France); Elleaume, Helene, E-mail: h.elleaume@esrf.fr [INSERM, U836, Institute of Neurosciences, Grenoble (France)

    2011-12-15

    In this report we have summarized our studies to optimize the delivery of boronophenylalanine (BPA) and sodium borocaptate (BSH) for boron neutron capture therapy (BNCT) of F98 glioma bearing rats. These results have been compared to a chemoradiotherapeutic approach using the same tumor model. The best survival data from our BNCT studies were obtained using a combination of BPA and sodium borocaptate BSH administered via the internal carotid artery, in combination with blood-brain barrier disruption (BBB-D). This treatment resulted in a mean survival time (MST) of 140 d with a 25% cure rate. The other approach combined intracerebral administration of carboplatin by either convection enhanced delivery (CED) or Alzet pump infusion, followed by external beam photon irradiation. This resulted in MSTs of 83 d and 112 d, respectively, with a cure rate of 40% for the latter. However, a significant problem that must be solved for both BNCT and this new chemoradiotherapeutic approach is how to improve drug uptake and microdistribution within the tumor.

  8. Comparison of intracerebral delivery of carboplatin and photon irradiation with an optimized regimen for boron neutron capture therapy of the F98 rat glioma

    International Nuclear Information System (INIS)

    In this report we have summarized our studies to optimize the delivery of boronophenylalanine (BPA) and sodium borocaptate (BSH) for boron neutron capture therapy (BNCT) of F98 glioma bearing rats. These results have been compared to a chemoradiotherapeutic approach using the same tumor model. The best survival data from our BNCT studies were obtained using a combination of BPA and sodium borocaptate BSH administered via the internal carotid artery, in combination with blood–brain barrier disruption (BBB-D). This treatment resulted in a mean survival time (MST) of 140 d with a 25% cure rate. The other approach combined intracerebral administration of carboplatin by either convection enhanced delivery (CED) or Alzet pump infusion, followed by external beam photon irradiation. This resulted in MSTs of 83 d and 112 d, respectively, with a cure rate of 40% for the latter. However, a significant problem that must be solved for both BNCT and this new chemoradiotherapeutic approach is how to improve drug uptake and microdistribution within the tumor.

  9. Boron Neutron Capture Therapy for Malignant Brain Tumors

    Science.gov (United States)

    MIYATAKE, Shin-Ichi; KAWABATA, Shinji; HIRAMATSU, Ryo; KUROIWA, Toshihiko; SUZUKI, Minoru; KONDO, Natsuko; ONO, Koji

    2016-01-01

    Boron neutron capture therapy (BNCT) is a biochemically targeted radiotherapy based on the nuclear capture and fission reactions that occur when non-radioactive boron-10, which is a constituent of natural elemental boron, is irradiated with low energy thermal neutrons to yield high linear energy transfer alpha particles and recoiling lithium-7 nuclei. Therefore, BNCT enables the application of a high dose of particle radiation selectively to tumor cells in which boron-10 compound has been accumulated. We applied BNCT using nuclear reactors for 167 cases of malignant brain tumors, including recurrent malignant gliomas, newly diagnosed malignant gliomas, and recurrent high-grade meningiomas from January 2002 to May 2014. Here, we review the principle and history of BNCT. In addition, we introduce fluoride-18-labeled boronophenylalanine positron emission tomography and the clinical results of BNCT for the above-mentioned malignant brain tumors. Finally, we discuss the recent development of accelerators producing epithermal neutron beams. This development could provide an alternative to the current use of specially modified nuclear reactors as a neutron source, and could allow BNCT to be performed in a hospital setting. PMID:27250576

  10. Neutron radiography of irradiated nuclear fuel at Idaho National Laboratory

    International Nuclear Information System (INIS)

    Neutron radiography of irradiated nuclear fuel provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Idaho National Laboratory (INL) has multiple nuclear fuels research and development programs that routinely evaluate irradiated fuels using neutron radiography. The Neutron Radiography reactor (NRAD) sits beneath a shielded hot cell facility where neutron radiography and other evaluation techniques are performed on these highly radioactive objects. The NRAD currently uses the foil-film transfer technique for imaging fuel that is time consuming but provides high spatial resolution. This study describes the NRAD and hot cell facilities, the current neutron radiography capabilities available at INL, planned upgrades to the neutron imaging systems, and new facilities being brought online at INL related to neutron imaging

  11. Simulation analysis of radiation fields inside phantoms for neutron irradiation

    International Nuclear Information System (INIS)

    Radiation fields inside phantoms have been calculated for neutron irradiation. Particle and heavy-ion transport code system PHITS was employed for the calculation. Energy and size dependences of neutron dose were analyzed using tissue equivalent spheres of different size. A voxel phantom of mouse was developed based on CT images of an 8-week-old male C3H/HeNs mouse. Deposition energy inside the mouse was calculated for 2- and 10-MeV neutron irradiation. (author)

  12. Present status of BNCT at Kyoto University Research Reactor Institute

    International Nuclear Information System (INIS)

    At Kyoto University Research Reactor Institute, we have two facilities for BNCT such as a reactor-based and an accelerator-based neutron source. In this article, we will present the characteristics overview of both facilities. (author)

  13. Effect of neutron energy and fluence on deuterium retention behaviour in neutron irradiated tungsten

    Science.gov (United States)

    Fujita, Hiroe; Yuyama, Kenta; Li, Xiaochun; Hatano, Yuji; Toyama, Takeshi; Ohta, Masayuki; Ochiai, Kentaro; Yoshida, Naoaki; Chikada, Takumi; Oya, Yasuhisa

    2016-02-01

    Deuterium (D) retention behaviours for 14 MeV neutron irradiated tungsten (W) and fission neutron irradiated W were evaluated by thermal desorption spectroscopy (TDS) to elucidate the correlation between D retention and defect formation by different energy distributions of neutrons in W at the initial stage of fusion reactor operation. These results were compared with that for Fe2+ irradiated W with various damage concentrations. Although dense vacancies and voids within the shallow region near the surface were introduced by Fe2+ irradiation, single vacancies with low concentration were distributed throughout the sample for 14 MeV neutron irradiated W. Only the dislocation loops were introduced by fission neutron irradiation at low neutron fluence. The desorption peak of D for fission neutron irradiated W was concentrated at low temperature region less than 550 K, but that for 14 MeV neutron irradiated W was extended toward the higher temperature side due to D trapping by vacancies. It can be said that the neutron energy distribution could have a large impact on irradiation defect formation and the D retention behaviour.

  14. In-phantom dosimetry for BNCT with Fricke and normoxic-polymer gels

    Science.gov (United States)

    Gambarini, G.; Agosteo, S.; Carrara, M.; Gay, S.; Mariani, M.; Pirola, L.; Vanossi, E.

    2006-05-01

    Measurements of in-phantom dose distributions and images are important for Boron Neutron Capture Therapy treatment planning. The method for spatial determination of absorbed doses in thermal or epithermal neutron fields, based on Fricke-xylenol-orange-infused gel dosimeters in form of layers, has revealed to be very reliable, as gel layer dosimeters give the possibility of obtaining spatial dose distributions and measurements of each dose contribution in neutron fields, by means of a properly studied procedure. Quite recently, BNCT has been applied to treat liver metastases; in this work the results of in-phantom dosimetry for explanted liver in BNCT treatments are described. Moreover, polyacrylamide gel (PAG) dosimeters in which a polymerization process appears as a consequence of absorbed dose, have been recently tested, because of their characteristic absence of diffusion. In fact, due to the diffusion of ferric ions, Fricke-gel dosimeters require prompt analysis after exposure to avoid spatial information loss. In this work the preliminary results of a study about the reliability of polymer gel in BNCT dosimetry are also discussed. Gel layers have been irradiated in a phantom exposed in the thermal column of the TRIGA MARK II reactor (Pavia). The results obtained with the two kinds of gel dosimeter have been compared.

  15. BNCT with linac, feasibility study

    International Nuclear Information System (INIS)

    High energy photon beams from Medical Linear Accelerators (linacs) which are used in radiotherapy produce undesirable neutrons, beside the clinically useful electron and photon beams. Neutrons are produced from the photonuclear reaction (γ,n) of high energy photons with high Z-materials which compose the accelerator head. In this paper the possible use of these undesirable neutrons for BNCT is investigated, making use of high energy linacs already installed in hospitals, primarily for high energy electron and photon therapy and applying them in the context of BNCT. The photoneutron components emitted by the accelerator is the source for Monte Carlo simulations of the interactions that take place within the head of a voxel-based phantom. The neutron flux across the phantom head is calculated using different moderator arrangements and different techniques in the aim of increasing the thermal neutron flux at the targeted site. Also, we shall test different configurations of the linac head to maximize the exposure of high-Z materials to the photon beam, including the removal of the flattening filter, so as to boost the photoneutron production in the linac head. Experimental work will be conducted in hospitals to validate the Monte Carlo simulations. To make use of linacs for BNCT will be advantageous in the sense that the setting in a hospital department is much more acceptable by the public than a reactor installation. This will mean less complications regarding patient positioning and movement with respect to the beams, additional patient transportation and management will be more cost effective. (author)

  16. Radiation field characterization of a BNCT research facility using Monte Carlo method - code MCNP-4B

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy - BNCT - is a selective cancer treatment and arises as an alternative therapy to treat cancer when usual techniques - surgery, chemotherapy or radiotherapy - show no satisfactory results. The main proposal of this work is to project a facility to BNCT studies. This facility relies on the use of an Am Be neutron source and on a set of moderators, filters and shielding which will provide the best neutron/gamma beam characteristic for these Becton studies, i.e., high intensity thermal and/or epithermal neutron fluxes and with the minimum feasible gamma rays and fast neutrons contaminants. A computational model of the experiment was used to obtain the radiation field in the sample irradiation position. The calculations have been performed with the MCNP 4B Monte Carlo Code and the results obtained can be regarded as satisfactory, i.e., a thermal neutron fluencyNT = 1,35x108 n/cm , a fast neutron dose of 5,86x10-10 Gy/NT and a gamma ray dose of 8,30x10-14 Gy/NT. (author)

  17. Reduction effects in rutile induced by neutron irradiation

    International Nuclear Information System (INIS)

    Reduction effect in rutile induced by neutron irradiation and its post-annealing experiment has been investigated. Rutile TiO2 (1 1 0) specimens were cut from the same crystal, and irradiated with high-fluence (1x1019 cm-2) neutron irradiation, then annealed in vacuum and oxidizing atmosphere at different temperatures, respectively. After irradiation, rutile shows deep dark-blue color. After oxidization, it becomes transparent again. But annealed in vacuum, the color of irradiated sample keeps invariable. By means of UV-VIS-IR, XPS, XRD and AFM, samples were investigated before and after irradiation, as well as after annealing. The results show that neutron irradiation induces O2- ions sputtering and Ti4+ ions reduce to Ti3+, Ti2+, even Ti+, and leads to metallization tendency, and the reduction of Ti4+ presents depth-distribution. Especially surface morphology shows step pattern and polycrystalline structure because of insufficiency of O2- ions

  18. Radiogenic silicon precipitates in neutron irradiated aluminum

    International Nuclear Information System (INIS)

    A theory of precipitation of radiogenic Si in Al is developed. The aim of this study is to predict quantitatively the variation of microstructural parameters such as precipitates number and sizes dependently on irradiation parameters. Analogy with deposition of thin films and formation of silver halides is discussed. A model for the precipitation of radiogenic Si in Al is developed on the basis of the theory of Ostwald-ripening in precipitation processes with constant rate addition of monomers. The model predicts that after the precipitation process enters the 'late' stage, the number of precipitates depends only on the ratio between the thermal and fast neutron fluxes but not on the absolute values of flux and fluence. A quantitative interpretation of the spectral effect, suggested by Farrell [Mater. Res. Soc. Symp. Proc. 373 (1995) 165] is given. The predictions of the model are compared with experimental results

  19. Thermal facility for BNCT in RA-1 Argentine research reactor

    International Nuclear Information System (INIS)

    Full text: A thermal facility for BNCT experiments is being developed in an Argentine Research Reactor: RA-1 'Enrico Fermi'. RA-1 research nuclear reactor is working at Constituyentes Atomic Center, near Buenos Aires, and started operations in 1958. It worked at several power levels, up to 120 k W. Today, RA-1 is licensed to work at 40 k W. RA-1 was used to produce radioisotopes in the early 60's, and today gives irradiation services to test materials, to calibrate detectors and activation analysis. RA-1 users are CNEA researchers, Nuclear Regulatory Authority staff and private laboratories. Boron Neutron Capture Therapy (BNCT) is a method to fight against cancer. It consists to irradiate cancer tumors using thermal neutrons. The tumor tissue should include a dose of a boron solution. The Boron irradiation produces the following nuclear reactions: n + B10→ α + Li7 + γ. Being the α particle a radiation with short range, but high destructive energy, the tumor cells are destroyed. The neutron flux should be of 109 n/cm2seg, and the gamma dose lower than 0.48 s V/h. This method is oriented to treat brain tumors. Taking in account that the brain tumors usually are several centimeters deep in the head, to get thermal neutrons in the tumor is convenient to irradiate the patient using epithermal neutrons. moderation in the cells of the brain will permit to get more thermal neutrons in the tumor. In CNEA BNCT program there is in construction an epithermal clinical facility in the RA-6, a 500 k W research reactor that is at Bariloche Atomic Center. To perform some experiments for instance to test the boron compounds, RA-1 is used. In this experiments little animals like hamsters or bottles with cultivated cells are used, for that reasons thermal neutrons are used. The project in RA-1 consists in several stages. As the first stage a preliminary thermal facility was built. Irradiation times of 45-60 minutes were estimated, at power operation levels of 40 k W. Several

  20. Determination of radiobiological parameters for the safe clinical application of BNCT

    International Nuclear Information System (INIS)

    In the present report the effects of BNCT irradiation on the skin and spinal cord of Fischer 344 rats, for known concentrations of 10B in the blood and these normal tissues, are compared with the effects of the neutron beam alone or photon irradiation. The biological effectiveness of irradiation in the presence of the capture agents BSH and BPA have been compared. Irradiations were carried out using the thermal beam of the Brookhaven Medical Research Reactor (BMRR). Therapy experiments were also carried out as part of this study, using the rat 9L-gliosarcoma cell line, in order to establish the potential therapeutic advantage that might be achieved using the above capture agents. This cell line grows as a solid tumor in vivo as well as in vitro. The implications of these findings, with respect to the clinical use of the Petten HBII based epithermal neutron beam, will be discussed

  1. Neutron Flux Characterization of Irradiation Holes for Irradiation Test at HANARO

    Science.gov (United States)

    Yang, Seong Woo; Cho, Man Soon; Choo, Kee Nam; Park, Sang Jun

    2016-02-01

    The High flux Advanced Neutron Application ReactOr (HANARO) is a unique research reactor in the Republic of Korea, and has been used for irradiation testing since 1998. To conduct irradiation tests for nuclear materials, the irradiation holes of CT and OR5 have been used due to a high fast-neutron flux. Because the neutron flux must be accurately calculated to evaluate the neutron fluence of irradiated material, it was conducted using MCNP. The neutron flux was measured using fluence monitor wires to verify the calculated result. Some evaluations have been conducted, however, more than 20% errors have frequently occurred at the OR irradiation hole, while a good agreement between the calculated and measured data was shown at the CT irradiation hole.

  2. Neutron Flux Characterization of Irradiation Holes for Irradiation Test at HANARO

    Directory of Open Access Journals (Sweden)

    Yang Seong Woo

    2016-01-01

    Full Text Available The High flux Advanced Neutron Application ReactOr (HANARO is a unique research reactor in the Republic of Korea, and has been used for irradiation testing since 1998. To conduct irradiation tests for nuclear materials, the irradiation holes of CT and OR5 have been used due to a high fast-neutron flux. Because the neutron flux must be accurately calculated to evaluate the neutron fluence of irradiated material, it was conducted using MCNP. The neutron flux was measured using fluence monitor wires to verify the calculated result. Some evaluations have been conducted, however, more than 20% errors have frequently occurred at the OR irradiation hole, while a good agreement between the calculated and measured data was shown at the CT irradiation hole.

  3. Photoneutron source for in-hospital BNCT treatment. Feasibility study

    International Nuclear Information System (INIS)

    Some recent studies in Italy have focused on the possibility of exploiting high energy electron linear accelerators, normally used in gamma radiotherapy, as photo-neutrons source for in-hospital medical applications. Neutrons are produced by Giant Dipole Resonance (GDR) reactions from high energy photons on high Z targets; by proper material and geometry optimization, interesting fluence rates of thermalized neutrons can be made available, with minimized fast neutron and gamma backgrounds, for a fractionated type of Boron Neutron Capture Therapy (BNCT) devoted to external treatment of some specific tumors. A photoneutron converter, constituted by high Z core and surrounded by Low Z materials, is shaped to produce thermal beam inside an irradiation cavity. A feasibility study on Beam Shaping Assembly using MCNPGN simulation code is performed on various geometrical shapes and material selection. A first prototype of the photoconverter has been realized and tested at some hospital high energy medical LINAC facilities. In this paper the preliminary experimental results of neutron fluence rate and neutron spectra produced by the photoconverter prototype are compared to the simulation data. (author)

  4. Neutron Absorbing Ability Variation in Neutron Absorbing Material Caused by the Neutron Irradiation in Spent Fuel Storage Facility

    International Nuclear Information System (INIS)

    In spent fuel storage facility like high density spent fuel storage racks and dry storage casks, spent fuels are stored with neutron absorbing materials installed as a part of those facilities, and they are used for absorbing neutrons emitted from spent fuels. Usually structural material with neutron absorbing material of racks and casks are located around spent fuels, so it is irradiated by neutrons for long time. Neutron absorbing ability could be changed by the variation of nuclide composition in neutron absorbing material caused by the irradiation of neutrons. So, neutron absorbing materials are continuously faced with spent fuels with boric acid solution or inert gas environment. Major nuclides in neutron absorbing material are Al27, C12, B11, B10 and they are changed to numerous other ones as radioactive decay or neutron absorption reaction. The B10 content in neutron absorbing material dominates the neutron absorbing ability, so, the variation of nuclide composition including the decrease of B10 content is the critical factor on neutron absorbing ability. In this study, neutron flux in spent fuel, the activation of neutron absorbing material and the variation of nuclide composition are calculated. And, the minimum neutron flux causing the decrease of B10 content is calculated in spent fuel storage facility. Finally, the variation of neutron multiplication factor is identified according to the one of B10 content in neutron absorbing material. The minimum neutron flux to impact the neutron absorbing ability is 1010 order, however, usual neutron flux from spent fuel is 108 order. Therefore, even though neutron absorbing material is irradiated for over 40 years, B10 content is little decreased, so, initial neutron absorbing ability could be kept continuously

  5. INEL BNCT Program: Volume 5, No. 9

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, A.L. (ed.)

    1991-01-01

    This Bulletin presents a summary of accomplishments and highlights of the Idaho National Engineering Laboratory's (INEL) Boron Neutron Capture Therapy (BNCT) Program for September 1991. This bulletin includes information on the brain tumor and melanoma research programs, Power Burst Facility (PBF) technical support and modifications, PBF operations, and updates to the animal data charts.

  6. Feasibility of BNCT radiobiological experiments at the HYTHOR facility

    Science.gov (United States)

    Esposito, J.; Ceballos, C.; Soncin, M.; Fabris, C.; Friso, E.; Moro, D.; Colautti, P.; Jori, G.; Rosi, G.; Nava, E.

    2008-06-01

    HYTHOR (HYbrid Thermal spectrum sHifter tapirO Reactor) is a new thermal-neutron irradiation facility, which was installed and became operative in mid 2005 at the TAPIRO (TAratura PIla Rapida potenza 0) fast reactor, in the Casaccia research centre (near Rome) of ENEA (Ente per le Nuove tecnologie Energia ed Ambiente). The facility has been designed for in vivo radiobiological studies. In HYTHOR irradiation cavity, 1-6 mice can be simultaneously irradiated to study skin melanoma treatments with the BNCT (boron neutron capture therapy). The therapeutic effects of HYTHOR radiation field on mouse melanoma has been studied as a preliminary investigation before studying the tumour local control due to boron neutron capture effect after boronated molecule injection. The method to properly irradiate small animals has been precisely defined. Results show that HYTHOR radiation field is by itself effective in reducing the tumour-growth rate. This finding has to be taken into account in studying the effectiveness of new 10B carriers. A method to properly measure the reduction of the tumour-growth rate is reported and discussed.

  7. Heavy Neutron Irradiation Test of Materials in Joyo Instrumented Rigs

    International Nuclear Information System (INIS)

    For studies of radiation effects in materials for advanced nuclear systems including a nuclear fusion reactor, heavy neutron irradiation by high energy neutrons is essential. A sodium cooled high flux fast reactor will be only a choice for realizing heavy neutron irradiation. The paper will describe the brief history of radiation effects study utilizing fission reactors in Japan, and the status of the fast reactor of JOYO in Japan, for applying it to the heavy irradiation of candidate materials for advanced nuclear systems. (author)

  8. Experimental Study on Response of Photomultiplier Tube to Neutron Irradiation

    International Nuclear Information System (INIS)

    The response of photomultiplier tube to neutron irradiation at energy range of 0.75-15 MeV was measured using white neutron source produced by the 9Be(d, n)10B reaction at HI-13 tandem accelerator in China Institute of Atomic Energy. Adopting the charge analog digital conversion technique and time-of-flight method, each pulse charge produced by a neutron was collected and recorded. Based on the mechanism of photomultiplier tube, the theoretical sensitivity to neutron irradiation was calculated by MCNP program and the calculated results agree with the experimental data. (authors)

  9. Calculations on neutron irradiation damage in reactor materials

    International Nuclear Information System (INIS)

    Neutron irradiation damage calculations were made for Mo, Nb, V, Fe, Ni and Cr. Firstly, damage functions were calculated as a function of neutron energy with neutron cross sections of elastic and inelastic scatterings, and (n,2n) and (n,γ) reactions filed in ENDF/B-III. Secondly, displacement damage expressed in displacements per atom (DPA) was estimated for neutron environments such as fission spectrum, thermal neutron reactor (JMTR), fast breeder reactor (MONJU) and two fusion reactors (The Conceptual Design of Fusion Reactor in JAERI and ORNL-Benchmark). then, damage cross section in units of dpa. barn was defined as a factor to convert a given neutron fluence to the DPA value, and was calculated for the materials in the above neutron environments. Finally, production rates of helium and hydrogen atoms were calculated with (n,α) and (n,p) cross sections in ENDF/B-III for the materials irradiated in the above reactors. (auth.)

  10. Review of the Advanced Neutron Source (ANS) materials irradiation facilities

    International Nuclear Information System (INIS)

    The purpose of the workshop was to document as accurately as possible the present and future needs for neutron irradiation capacity and facilities as related to the design of the Advanced Neutron Source (ANS) which will be the next generation steady-state research reactor. The report provides the findings and recommendations of the working group. After introductory and background information is presented, the discussion includes the status of the ANS design, in particular in-core materials irradiation facilities design and important experimental parameters. The summary of workshop discussions describes a survey of irradiation-effects research community and opportunities for ex-core irradiation facilities. 20 refs., 2 figs., 4 tabs

  11. Needs of in-situ materials testing under neutron irradiation

    International Nuclear Information System (INIS)

    Under neutron irradiation, the component atoms of materials are displaced as primary knock-on atoms, and the energy of the primary knock-on atoms is consumed by electron excitation and nuclear collision. Elementary irradiation defects accumulate to form damage structure including voids and bubbles. In situ test under neutron irradiation is necessary for investigating into the effect of irradiation on creep behavior, the electric properties of ceramics, transport phenomena and so on. The in situ test is also important to investigate into the phenomena related to the chemical reaction with environment during irradiation. Accelerator type high energy neutron sources are preferable to fission reactors. In this paper, the needs and the research items of in situ test under neutron irradiation using a D-Li stripping type high energy neutron source on metallic and ceramic materials are described. Creep behavior is one of the most important mechanical properties, and depends strongly on irradiation environment, also it is closely related to microstructure. Irradiation affects the electric conductibity of ceramics and also their creep behavior. In this way, in situ test is necessary. (K.I.)

  12. Study of damages by neutron irradiation in lithium aluminates

    International Nuclear Information System (INIS)

    Lithium aluminates proposed to the production of tritium in fusion nuclear reactors, due to the thermal stability that they present as well as the behavior of the aluminium to the irradiation. As a neutron flux with profile (≅ 14 Mev) of a fusion reactor is not available. A irradiation experiment was designed in order to know the micro and nano structure damages produced by fast and thermal neutrons in two irradiation positions of the fusion nuclear reactor Triga Mark III: CT (Thermal Column) and SIFCA (System of Irradiation Fixed of Capsules). In this work samples of lithium aluminate were characterized by XRD (X-Ray Diffraction), TEM (Transmission Electron Microscopy) and SEM (Scanning Electron Microscopy). Two samples were prepared by two methods: a) coalition method and b) peroxide method. This characterization comprised original and irradiated samples. The irradiated sample amounted to 4 in total: one for each preparation method and one for each irradiation position. The object of this analysis was to correlate with the received neutron dose the damages suffered by the samples with the neutron irradiation during long periods (440 H), in their micro and nano structure aspects; in order to understand the changes as a function of the irradiation zone (with thermal and fast neutron flux) and the preparation methods of the samples and having as an antecedent the irradiation in SIFCA position by short times (2h). The obtained results are referred to the stability of γ -aluminate phase, under given conditions of irradiation and defined nano structure arrangement. They also refer to the proposals of growth mechanism and nucleation of new phases. The error associated with the measurement of neutron dose is also discussed. (Author)

  13. The intrinsic gettering in neutron irradiation Czochralski-silicon

    CERN Document Server

    Li Yang Xian; Niu Ping Juan; Liu Cai Chi; Xu Yue Sheng; Yang Deren; Que Duan Lin

    2002-01-01

    The intrinsic gettering in neutron irradiated Czochralski-silicon is studied. The result shows that a denuded zone at the surface of the neutron irradiated Czochralski-silicon wafer may be formed through one-step short-time annealing. The width of the denuded zone is dependent on the annealing temperature and the dose of neutron irradiation, while it is irrelated to the annealing time in case the denuded zone is formed. The authors conclude that the interaction between the defects induced by neutron irradiation and the oxygen in the silicon accelerates the oxygen precipitation in the bulk, and becomes the dominating factor of the quick formation of intrinsic gettering. It makes the effect of thermal history as the secondary factor

  14. Voxel model in BNCT treatment planning: performance analysis and improvements

    Science.gov (United States)

    González, Sara J.; Carando, Daniel G.; Santa Cruz, Gustavo A.; Zamenhof, Robert G.

    2005-02-01

    In recent years, many efforts have been made to study the performance of treatment planning systems in deriving an accurate dosimetry of the complex radiation fields involved in boron neutron capture therapy (BNCT). The computational model of the patient's anatomy is one of the main factors involved in this subject. This work presents a detailed analysis of the performance of the 1 cm based voxel reconstruction approach. First, a new and improved material assignment algorithm implemented in NCTPlan treatment planning system for BNCT is described. Based on previous works, the performances of the 1 cm based voxel methods used in the MacNCTPlan and NCTPlan treatment planning systems are compared by standard simulation tests. In addition, the NCTPlan voxel model is benchmarked against in-phantom physical dosimetry of the RA-6 reactor of Argentina. This investigation shows the 1 cm resolution to be accurate enough for all reported tests, even in the extreme cases such as a parallelepiped phantom irradiated through one of its sharp edges. This accuracy can be degraded at very shallow depths in which, to improve the estimates, the anatomy images need to be positioned in a suitable way. Rules for this positioning are presented. The skin is considered one of the organs at risk in all BNCT treatments and, in the particular case of cutaneous melanoma of extremities, limits the delivered dose to the patient. Therefore, the performance of the voxel technique is deeply analysed in these shallow regions. A theoretical analysis is carried out to assess the distortion caused by homogenization and material percentage rounding processes. Then, a new strategy for the treatment of surface voxels is proposed and tested using two different irradiation problems. For a parallelepiped phantom perpendicularly irradiated with a 5 keV neutron source, the large thermal neutron fluence deviation present at shallow depths (from 54% at 0 mm depth to 5% at 4 mm depth) is reduced to 2% on average

  15. Voxel model in BNCT treatment planning: performance analysis and improvements

    International Nuclear Information System (INIS)

    In recent years, many efforts have been made to study the performance of treatment planning systems in deriving an accurate dosimetry of the complex radiation fields involved in boron neutron capture therapy (BNCT). The computational model of the patient's anatomy is one of the main factors involved in this subject. This work presents a detailed analysis of the performance of the 1 cm based voxel reconstruction approach. First, a new and improved material assignment algorithm implemented in NCTPlan treatment planning system for BNCT is described. Based on previous works, the performances of the 1 cm based voxel methods used in the MacNCTPlan and NCTPlan treatment planning systems are compared by standard simulation tests. In addition, the NCTPlan voxel model is benchmarked against in-phantom physical dosimetry of the RA-6 reactor of Argentina. This investigation shows the 1 cm resolution to be accurate enough for all reported tests, even in the extreme cases such as a parallelepiped phantom irradiated through one of its sharp edges. This accuracy can be degraded at very shallow depths in which, to improve the estimates, the anatomy images need to be positioned in a suitable way. Rules for this positioning are presented. The skin is considered one of the organs at risk in all BNCT treatments and, in the particular case of cutaneous melanoma of extremities, limits the delivered dose to the patient. Therefore, the performance of the voxel technique is deeply analysed in these shallow regions. A theoretical analysis is carried out to assess the distortion caused by homogenization and material percentage rounding processes. Then, a new strategy for the treatment of surface voxels is proposed and tested using two different irradiation problems. For a parallelepiped phantom perpendicularly irradiated with a 5 keV neutron source, the large thermal neutron fluence deviation present at shallow depths (from 54% at 0 mm depth to 5% at 4 mm depth) is reduced to 2% on average

  16. Measurement of spatial distribution of neutrons and gamma rays for BNCT using multi-imaging plate system.

    Science.gov (United States)

    Tanaka, Kenichi; Sakurai, Yoshinori; Tanaka, Hiroki; Kajimoto, Tsuyoshi; Takata, Takushi; Takada, Jun; Endo, Satoru

    2015-12-01

    Quality assurance of the spatial distributions of neutrons and gamma rays was tried using imaging plates (IPs) and converters to enhance the beam components in the epithermal neutron mode of the Kyoto University Reactor. The converters used were 4mm thick epoxy resin with B4C at 6.85 weight-percent (wt%) (10)B for epithermal neutrons, and 3mm thick carbon for gamma rays. Results suggested that the IP signal does not need a sensitivity correction regardless of the incident radiation that produces it. PMID:26278346

  17. Effects of neutron irradiation on high temperature superconductors

    OpenAIRE

    Hammerer, John J.

    1988-01-01

    Approved for public release; distribution in unlimited. Neutron irradiation of high temperature superconductors was performed in order to determine the effects of nuclear weapons on these novel materials. This radiation could also be encountered in space radiation belts, fusion reactors and particle accelerators. Fluences used were on the order of 10 to the 18th power fast and thermal neutrons/sq cm. The result of the irradiation was a complete loss of observed superconductivity in YBa2Cu3...

  18. Hydriding and neutron irradiation in zircaloy-4

    International Nuclear Information System (INIS)

    The composition of Zircaloy-4 for nuclear applications is specified by the ASTM B350 Standard, that fixes the amount of alloying elements (Sn, Fe, Cr) and impurities (Ni, Hf, O, N, C, among others) to optimize good corrosion and mechanical behavior.The recycling of zircaloy-4 scrap and chips resulting from cladding tube fabrication is an interesting issue.However, changes in the final composition of the recycled material may occur due to contamination with tool pieces, stainless steel chips, turnings, etc. while scrap is stored and handled. Since the main components of the possible contaminants are Fe, Cr and Ni, it arises the interest in studying up to what limit the Fe, Ni and Cr contents could be exceeded beyond the standard specification without affecting significantly the alloy properties.Zircaloy-4 alloys elaborated with Fe, Cr and Ni additions and others of standard composition in use in nuclear plants are studied by tensile tests, SEM observations and EDS microanalysis.Some samples are tested in the initial condition and others after hydriding treatments and neutron irradiation in the RA6

  19. Evaluation of Neutron Irradiated Silicon Carbide and Silicon Carbide Composites

    Energy Technology Data Exchange (ETDEWEB)

    Newsome G, Snead L, Hinoki T, Katoh Y, Peters D

    2007-03-26

    The effects of fast neutron irradiation on SiC and SiC composites have been studied. The materials used were chemical vapor deposition (CVD) SiC and SiC/SiC composites reinforced with either Hi-Nicalon{trademark} Type-S, Hi-Nicalon{trademark} or Sylramic{trademark} fibers fabricated by chemical vapor infiltration. Statistically significant numbers of flexural samples were irradiated up to 4.6 x 10{sup 25} n/m{sup 2} (E>0.1 MeV) at 300, 500 and 800 C in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Dimensions and weights of the flexural bars were measured before and after the neutron irradiation. Mechanical properties were evaluated by four point flexural testing. Volume increase was seen for all bend bars following neutron irradiation. Magnitude of swelling depended on irradiation temperature and material, while it was nearly independent of irradiation fluence over the fluence range studied. Flexural strength of CVD SiC increased following irradiation depending on irradiation temperature. Over the temperature range studied, no significant degradation in mechanical properties was seen for composites fabricated with Hi-Nicalon{trademark} Type-S, while composites reinforced with Hi-Nicalon{trademark} or Sylramic fibers showed significant degradation. The effects of irradiation on the Weibull failure statistics are also presented suggesting a reduction in the Weibull modulus upon irradiation. The cause of this potential reduction is not known.

  20. Expectation for energy selective neutron source based on the current neutron irradiation study of materials

    International Nuclear Information System (INIS)

    For an effective utilization of superior characteristics of the energy selective high energy neutron source, a consideration was made. Electron irradiation with high voltage electron microscopes (HVEM), D-T fusion neutron irradiation with rotating target neutron source (RTNS-II), and fission neutron irradiation with fission reactors were referred. The expected Energy Selective Neutron Source (ESNS) were compared with different types of irradiation facilities in regard to energy spectrum, flux stability, temperature control, and possibility of in-situ experiments. The excellent performance of HVEM electron irradiation, and of RTNS-II D-T fusion neutron irradiation was exemplified. The possibility of extending these excellent performances to the future ESNS experiment was discussed. Difficulties in the neutron irradiation experiment with fission reactors were exemplified. Shrinkage and growth of these difficulties in the ESNS experiment was discussed. Expected advantage and limitation of the ESNS was evaluated. Finally the positioning of ESNS was made, and the importance of its complementality with other facilities was pointed out. (M.T.)

  1. Results on Neutron and Gamma Irradiation of Electrolytic Tilmeters

    International Nuclear Information System (INIS)

    We report on irradiation studies done to a sample of high precision electrolytic tiltmeters with gamma-rays, up to a maximum dose of 150 kGy, an neutrons, up to a maximum fluence 1.5x10''14 cm''2. The effect of the irradiation on their performance is discussed. (Author) 19 refs

  2. Bioneutronics: Thermal scattering in organics tissues and its impact on BNCT dosimetry

    International Nuclear Information System (INIS)

    Neutron transport calculation is a key factor in BNCT numerical dosimetry assessments where thermal neutron flux is intimately related to the neutron dose, specially, the therapeutic boron dose. In this work, numerical calculations in phantoms were performed to determine the importance of utilizing the appropriate thermal scattering treatment for different organic tissues. Two thermal treatments for the neutron scattering were included in the simulations: hydrogen bounded in bulk water and hydrogen bounded in a lipid like carbon chain (polyethylene). The results showed difference between both thermal treatments that can reach several percent points depending on the type of source and irradiated geometry. - Highlights: • The impact of the thermal scattering data in BNCT dosimetry calculations was studied. • Thermal treatment for H in bulk water and H in a carbon chain was considered. • Calculations of thermal neutron flux and dose profiles in phantoms were performed. • The results show differences between both thermal treatments. • The importance of utilizing the correct thermal data for tissues was determined

  3. Tensile and fracture toughness test results of neutron irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Chaouadi, R.; Moons, F.; Puzzolante, J.L. [Centre d`Etude de l`Energie Nucleaire, Mol (Belgium)

    1998-01-01

    Tensile and fracture toughness test results of four Beryllium grades are reported here. The flow and fracture properties are investigated by using small size tensile and round compact tension specimens. Irradiation was performed at the BR2 material testing reactor which allows various temperature and irradiation conditions. The fast neutron fluence (>1 MeV) ranges between 0.65 and 2.45 10{sup 21} n/cm{sup 2}. In the meantime, un-irradiated specimens were aged at the irradiation temperatures to separate if any the effect of temperature from irradiation damage. Test results are analyzed and discussed, in particular in terms of the effects of material grade, test temperature, thermal ageing and neutron irradiation. (author)

  4. INEEL BNCT Research Program Annual Report, CY-2000

    Energy Technology Data Exchange (ETDEWEB)

    Venhuizen, James Robert

    2001-03-01

    This report is a summary of the activities conducted in conjunction with the Idaho National Engineering and Environmental Laboratory (INEEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 2000. Applications of supportive research and development, as well as technology deployment in the fields of chemistry, radiation physics and dosimetry, neutron source design and demonstration, and support the Department of Energy’s (DOE) National BNCT Program goals are the goals of this Program. Contributions from the individual contributors about their projects are included, specifically described are the following, chemistry: analysis of biological samples and an infrared blood-boron analyzer, and physics: progress in the patient treatment planning software, measurement of neutron spectra for the Argentina RA-6 reactor, and recalculation of the Finnish research reactor FiR 1 neutron spectra, BNCT accelerator technology, and modification to the research reactor at Washington State University for an epithermal-neutron beam.

  5. In-phantom dosimetry using the 13C(d,n)14N reaction for BNCT (boron neutron capture therapy)

    International Nuclear Information System (INIS)

    The use of the 13 C(d,n)14 N reaction at Ed =1.5 MeV for accelerator-based boron neutron capture therapy is investigated. The 13 C(d,n)14 N reaction presents the advantages of carbon as a target material and its large cross section. The deuteron beam was produced by a tandem accelerator at MIT's Laboratory for Accelerator Beam Applications. The resulting neutron spectra were evaluated in terms of RBE-dose rates at different depths inside a water-filled brain phantom using a heavy water moderator and lead reflector assembly. All results were simulated using the code MCNP. (author)

  6. Neutron irradiation tests on diagnostic components at JAERI

    Energy Technology Data Exchange (ETDEWEB)

    Nishitani, T. E-mail: nisitani@naka.jaeri.go.jp; Shikama, T.; Fukao, M.; Reichle, R.; Sugie, T.; Kakuta, T.; Kasai, S.; Snider, R.; Yamamoto, S

    2001-10-01

    As a part of the R and D program of the ITER Engineering Design Activities (EDA), we have carried out irradiation tests on a number of diagnostic components. In this paper the recent results of neutron irradiation tests on diagnostic windows, bolometer substrates and magnetic coils at JAERI are described. UV range transmission losses of a KU-1 quartz glass were measured during 14 MeV neutron irradiation at the Fusion Neutronics Source (FNS) with neutron fluences of up to 7.4x10{sup 19} n/m{sup 2}. Significant transmission losses were observed in the wavelength of 200-300 nm. Mica substrates of bolometers were irradiated at the Japan Material Testing Reactor (JMTR) with neutron fluence between 1x10{sup 22} and 2.2x10{sup 23} n/m{sup 2}. The size expansion was found to be only 0.13% at 2.2x10{sup 23} n/m{sup 2} and 150 deg. C, which gives us the good prospect of the bolometer in the ITER-FEAT application. Magnetic coils made with four kinds of Mineral Insulated (MI) cables have been irradiated in JMTR up to a fast neutron fluence of 1.1x10{sup 24} n/m{sup 2}. Radiation Induced Electrical Motive Force (RIEMF) of several volts was observed between core inductor and sheath of the MI cable.

  7. Neutron irradiation behavior of different classes of carbons

    International Nuclear Information System (INIS)

    The electronic properties of various carbons have been studied as a function of irradiation (neutron) dose and annealing. A general interpretation in terms of positive holes (in the valence band) and localized or delocalized paramagnetic centres created by the displacement of carbon atoms due to neutron irradiation is given. Different classes of carbons may be defined and an ''equivalent dose'' is used to characterize each carbon in its class. The irradiation and annealing behavior of graphites and pyrocarbons may also be visualized through their ''paths'' in a Hall effect - magnetic susceptibility two-dimensional space

  8. Neutron and gamma irradiation damage to organic materials.

    Energy Technology Data Exchange (ETDEWEB)

    White, Gregory Von, II; Bernstein, Robert

    2012-04-01

    This document discusses open literature reports which investigate the damage effects of neutron and gamma irradiation on polymers and/or epoxies - damage refers to reduced physical chemical, and electrical properties. Based on the literature, correlations are made for an SNL developed epoxy (Epon 828-1031/DDS) with an expected total fast-neutron fluence of {approx}10{sup 12} n/cm{sup 2} and a {gamma} dosage of {approx}500 Gy received over {approx}30 years at < 200 C. In short, there are no gamma and neutron irradiation concerns for Epon 828-1031/DDS. To enhance the fidelity of our hypotheses, in regards to radiation damage, we propose future work consisting of simultaneous thermal/irradiation (neutron and gamma) experiments that will help elucidate any damage concerns at these specified environmental conditions.

  9. Collaborative Physical and Biological Dosimetry Studies for Neutron Capture Therapy at the RA-1 Research Reactor Facility

    Energy Technology Data Exchange (ETDEWEB)

    David W. Nigg; Amanda E. Schwint; John K. Hartwell; Elisa M. Heber; Veronica Trivillin; Jorge Castillo; Luis Wentzeis; Patrick Sloan; Charles A. Wemple

    2004-10-01

    Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminiscent dosimeters to characterize the BNCT irradiation facility developed at the RA-1 research reactor operated by the Argentine National Atomic Energy Commission in Buenos Aires. Some biological scoping irradiations have also been completed using a small-animal (hamster) oral mucosa tumor model. Results indicate that the RA-1 neutron source produces useful dose rates but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications.

  10. Collaborative Physical and Biological Dosimetry Studies for Neutron Capture Therapy at the RA-1 Research Reactor Facility

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, D.W.; Schwint, A.E.; Hartwell, J.K.; Heber, E.M.; Trivillin, V.; Castillo, J.; Wentzeis, L.; Sloan, P.; Wemple, C.A.

    2004-10-04

    Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminiscent dosimeters to characterize the BNCT irradiation facility developed at the RA-1 research reactor operated by the Argentine National Atomic Energy Commission in Buenos Aires. Some biological scoping irradiations have also been completed using a small-animal (hamster) oral mucosa tumor model. Results indicate that the RA-1 neutron source produces useful dose rates but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications.

  11. Cold neutron irradiation facility for the Brazilian research reactors

    International Nuclear Information System (INIS)

    Neutron irradiation in research reactors and accelerators can be realized at appropriated neutron guides or beam holes shared around a cold neutron source (CNS) with neutron of variable intensity and energy. An irradiation facility for multiple applications including an intense CNS was calculated for the three Brazilian research reactors and can be utilized as a first concept for the new research reactor to be designed, the Brazilian multiple purpose research reactor (RMB). A study about coolant and moderators properties, and simulations with neutron physics and thermal codes, may be important for the definition of the type of the CNS to be utilized. Some earlier results of MCNP simulations and a discussion about the different factors involved in the definition of its installation in the Brazilian research reactors are here presented. One suggests an international cooperation for the design development of this system and posterior construction of a prototype in the Argonauta reactor at the Instituto de Engenharia Nuclear (IEN-CNEN/RJ). It is also being considered the inclusion of other devices as a neutron fiber to guide the neutron beams away of the gamma radiation and fast neutron background. The cold neutron facility increases the intensity of cold neutrons, without the need of additional fuel burn up. (author)

  12. Subcellular targets of mercaptoborate (BSH), a carrier of 10B for neutron capture therapy (BNCT) of brain tumors

    Czech Academy of Sciences Publication Activity Database

    Mareš, Vladislav; Krajčí, D.; Lisá, Věra

    2003-01-01

    Roč. 52, č. 5 (2003), s. 629-635. ISSN 0862-8408 R&D Projects: GA MPO FD-K/048 Institutional research plan: CEZ:AV0Z5011922 Keywords : thermal neutrons * brain tumors * sodium borocaptate Subject RIV: FD - Oncology ; Hematology Impact factor: 0.939, year: 2003

  13. Proceedings of the seminar on the utilization of neutron irradiation

    International Nuclear Information System (INIS)

    Japan Atomic Energy Research Institute (JAERI) is providing many research facilities for the research use not only by JAERI's researchers but also by the researchers who belong to the other organizations. The procedure of the utilization, related technology development, future plan of the facilities and so on, are discussed in the 'Advisory Council for JAERI's Research Facilities' since the council was established in 1999. More specific aspects of the utilization concerning the neutron irradiation tests and neutron activation analysis using JMTR, JRR-3M and JRR-4, and the post irradiation examinations in the hot laboratories, are discussed in the 'Program Committee for Neutron Irradiation'. The 'Seminar on the Utilization of Neutron Irradiation' was held on March 9th 2000 in Tokai establishment as a part of activities of the program committee. The topics presented in the seminar included the recent irradiation studies on the materials for the light water reactors, development of fusion reactor materials and materials used under high temperature, application of neutron activation and recent activities in the post irradiation examinations. Active discussions and opinions of the users were presented in the seminar, which were very useful in respect of feed back for the operation and management of the facilities. This report contains the shortpapers and the copies of the OHPs presented at the seminar. (author)

  14. The study of physics and safety characteristics for In-Hospital Neutron Irradiator (IHNI)

    International Nuclear Information System (INIS)

    The IHNI is designed with low-enrichment 235U (LEU) for Boron Neutron Capture Therapy (BNCT) based on Miniature Neutron Source Reactor (MNSR). The IHNI, operated with thermal power 30kW, is an under-moderated reactor of pool-tank type, and UO2 as fuel, light water as coolant and moderator, and metallic beryllium as reflector. The paper gives the physics and safety characteristics of IHNI. The physics characteristics include those parameters of the criticality and the beam port used for BNCT. The safety characteristics compare the safety parameters between reactor core of LEU and HEU. The result shows that LEU could meet the requirements of criticality and flux at exit of each beam. Furthermore, the better safety characteristics could approach by adopting the LEU in comparison with HEU. (author)

  15. A case of astrocytoma, 19 year history after BNCT

    International Nuclear Information System (INIS)

    A 39-year-old man had received Boron Neutron Capture Therapy (BNCT) in 1987 for a Grade II Astrocytoma. He gradually exacerbated and received a second operation in 1994. The mass taken in the second operation is almost competent with radiation necrosis. Following that, he shows no signs of recurrence. Currently, he has returned to full time employment in physical labor. This case suggests effectiveness of BNCT for rather low-grade astrocytomas. (author)

  16. Study of boron carbide evolution under neutron irradiation

    International Nuclear Information System (INIS)

    Owing to its high neutron efficiency, boron carbide (B4C) is used as a neutron absorber in control rods of nuclear plants. Its behaviour under irradiation has been extensively studied for many years. It now seems clear that brittleness of the material induced by the 10B(n,α)7Li capture reaction is due to penny shaped helium bubbles associated to a high strain field around them. However, no model explains the behaviour of the material under neutron irradiation. In order to build such a model, this work uses different techniques: nuclear microprobe X-ray diffraction profile analysis and Raman and Nuclear Magnetic Resonance Spectroscopy to present an evolution model of B4C under neutron irradiation. The use of nuclear reactions produced by a nuclear microprobe such as the 7Li(p,p'γ)7Li reaction, allows to measure lithium profile in B4C pellets irradiated either in Pressurised Water Reactors or in Fast Breeder Reactors. Examining such profiles enables us to describe the migration of lithium atoms out of B4C materials under neutron irradiation. The analysis of X-ray diffraction profiles of irradiated B4C samples allows us to quantify the concentrations of helium bubbles as well as the strain fields around such bubbles.Furthermore Raman spectroscopy studies of different B4C samples lead us to propose that under neutron irradiation. the CBC linear chain disappears. Such a vanishing of this CBC chain. validated by NMR analysis, may explain the penny shaped of helium bubbles inside irradiated B4C. (author)

  17. Biological Effects of Neutron and Proton Irradiations. Vol. I. Proceedings of the Symposium on Biological Effects of Neutron Irradiations

    International Nuclear Information System (INIS)

    During recent years the interest in biological effects caused by neutrons has been increasing steadily as a result of the rapid development of neutron technology and the great number of neutron sources being used. Neutrons, because of their specific physical characteristics and biological effects, form a special type of radiation hazard but, at the same time, are a prospective tool for applied radiobiology. This Symposium, held in Brookhaven at the invitation of the United States Government from 7-11 October 1963, provided an opportunity for scientists to discuss the experimental information at present available on the biological action of neutrons and to evaluate future possibilities. It was a sequel to the Symposium on Neutron Detection, Dosimetry and Standardization, which was organized by the International Atomic Energy Agency in December 1962 at Harwell. The Symposium was attended by 128 participants from 17 countries and 6 international organizations. Fifty-four papers were presented. The following subjects were discussed in various sessions: (1) Dosimetry. Estimation of absorbed dose of neutrons in biological material. (2) Biological effects of high-energy protons. (3) Cellular and genetic effects. (4) Pathology of neutron irradiation, including acute and chronic radiation syndromes (mortality, anatomical and histological changes, biochemical and metabolic disturbances) and delayed consequences. (5) Relative biological effectiveness of neutrons evaluated by different biological tests. A Panel on Biophysical Considerations in Neutron Experimentation, with special emphasis on informal discussions, was organized during the Symposium. The views of the Panel are recorded in Volume II of the Proceedings. Many reports were presented on the important subject of the relative effectiveness of the biological action of neutrons, as well as on the general pathology of neutron irradiation and the cellular and genetic effects related to it. Three survey papers considered

  18. Biological Effects of Neutron and Proton Irradiations. Vol. II. Proceedings of the Symposium on Biological Effects of Neutron Irradiations

    International Nuclear Information System (INIS)

    During recent years the interest in biological effects caused by neutrons has been increasing steadily as a result of the rapid development of neutron technology and the great number of neutron sources being used. Neutrons, because of their specific physical characteristics and biological effects, form a special type of radiation hazard but, at the same time, are a prospective tool for applied radiobiology. This Symposium, held in Brookhaven at the invitation of the United States Government from 7-11 October 1963, provided an opportunity for scientists to discuss the experimental information at present available on the biological action of neutrons and to evaluate future possibilities. It was a sequel to the Symposium on Neutron Detection, Dosimetry and Standardization, which was organized by the International Atomic Energy Agency in December 1962 at Harwell. The Symposium was attended by 128 participants from 17 countries and 6 international organizations. Fifty-four papers were presented. The following subjects were discussed in various sessions: (1) Dosimetry. Estimation of absorbed dose of neutrons in biological material. (2) Biological effects of high-energy protons. (3) Cellular and genetic effects. (4) Pathology of neutron irradiation, including acute and chronic radiation syndromes (mortality, anatomical and histological changes, biochemical and metabolic disturbances) and delayed consequences. (5) Relative biological effectiveness of neutrons evaluated by different biological tests. A Panel on Biophysical Considerations in Neutron Experimentation, with special emphasis on informal discussions, was organized during the Symposium. The views of the Panel are recorded in Volume II of the Proceedings. Many reports were presented on the important subject of the relative effectiveness of the biological action of neutrons, as well as on the general pathology of neutron irradiation and the cellular and genetic effects related to it. Three survey papers considered

  19. Current practices and future directions of therapeutic strategy in glioblastoma: Survival benefit and indication of BNCT

    International Nuclear Information System (INIS)

    Since 1998, we are performing clinical studies on treatment of GBM using conventional fractionated photon radiation therapy (CRT), proton beam therapy (PBT) or boron neutron capture therapy (BNCT). We investigated whether these radiation modalities improves the survival of patients with GBM. Sixty-eight cases of newly diagnosed GBM have been treated in our institution. After surgery, radiation therapy was performed using CRT with a dose of 60.0-61.2 Gy (n=36), hyperfractionated PBT concomitant with fractionated photon irradiation with a total dose of 96.6 Gy (n=17), or a single fraction of BNCT (n=15). In PBT, the surrounding volume of 2 cm from main tumor mass and the volume of perifocal edema were irradiated at dose of 75.6 and 60 Gy, respectively. The median OS time of the case series of BNCT for GBM has been reported as 13-20.7 M. In this study, the median OS and median time to MR change (TTM) for all patients were 25.7 and 11.9 M, respectively. The 1- and 2-year survival rates were 85.7% and 45.5%, respectively. On the other hand, in the patients who underwent CRT and ACNU-based chemotherapy, OS and 2-year survival rate were 14.2 M and 17.9%, respectively. In the patients who underwent high-dose PBT, OS and 2-year survival rate were 21.3 M and 38.5%, respectively. The present small case series of selected patients showed survival benefit after BNCT. The comparison using previously reported prognostic factor-based classifications suggest that outcome of BNCT in terms of survival appeared to have non-inferiority compared to the standard therapy. With respect to the case series as a high-dose radiation trial, the outcome (OS: 9.5-25 M) of previously reported may still be comparable to that of BNCT. Randomized trials of comparably selected patients are required to demonstrate conclusively that prolonged survival is a result of this tumor-selective radiotherapy.

  20. Biodistribution of the boron carriers boronophenylalanine (BPA) and/or decahydrodecaborate (GB-10) for Boron Neutron Capture Therapy (BNCT) in an experimental model of lung metastases

    International Nuclear Information System (INIS)

    BNCT was proposed for the treatment of diffuse, non-resectable tumors in the lung. We performed boron biodistribution studies with 5 administration protocols employing the boron carriers BPA and/or GB-10 in an experimental model of disseminated lung metastases in rats. All 5 protocols were non-toxic and showed preferential tumor boron uptake versus lung. Absolute tumor boron concentration values were therapeutically useful (25–76 ppm) for 3 protocols. Dosimetric calculations indicate that BNCT at RA-3 would be potentially therapeutic without exceeding radiotolerance in the lung. - Highlights: • We performed experimental boron biodistribution studies for lung metastases. • 3 protocols employing BPA and GB-10 would be therapeutically useful. • BNCT at RA-3 would be potentially therapeutic for experimental lung metastases

  1. Increase of the beam intensity for BNCT by changing the core configuration at THOR

    International Nuclear Information System (INIS)

    In this article, we will consider several core configurations and run the core calculation with MCNP to obtain the neutrons distribution at THOR. The thermal neutron flux inside the vertical tubes (VT-B-VT-E) and the fast neutron flux in the first row facing to the boron neutron capture therapy (BNCT) facility (I3-I5) were tallied for indication. Based on these simulation results, the fuel elements were rearranged during the annual repair period in 2007. The epithermal neutron flux at the center of BNCT beam exit in air was measured again, and the results showed that the beam intensity increased by 50%. Comparing the neutron intensities both in reactor core and at the BNCT beam exit for several core configurations, the results show that the BNCT beam intensity can be increased without decreasing the neutron intensity in core.

  2. Boron neutron capture therapy induces cell cycle arrest and cell apoptosis of glioma stem/progenitor cells in vitro

    International Nuclear Information System (INIS)

    Glioma stem cells in the quiescent state are resistant to clinical radiation therapy. An almost inevitable glioma recurrence is due to the persistence of these cells. The high linear energy transfer associated with boron neutron capture therapy (BNCT) could kill quiescent and proliferative cells. The present study aimed to evaluate the effects of BNCT on glioma stem/progenitor cells in vitro. The damage induced by BNCT was assessed using cell cycle progression, apoptotic cell ratio and apoptosis-associated proteins expression. The surviving fraction and cell viability of glioma stem/progenitor cells were decreased compared with differentiated glioma cells using the same boronophenylalanine pretreatment and the same dose of neutron flux. BNCT induced cell cycle arrest in the G2/M phase and cell apoptosis via the mitochondrial pathway, with changes in the expression of associated proteins. Glioma stem/progenitor cells, which are resistant to current clinical radiotherapy, could be effectively killed by BNCT in vitro via cell cycle arrest and apoptosis using a prolonged neutron irradiation, although radiosensitivity of glioma stem/progenitor cells was decreased compared with differentiated glioma cells when using the same dose of thermal neutron exposure and boronophenylalanine pretreatment. Thus, BNCT could offer an appreciable therapeutic advantage to prevent tumor recurrence, and may become a promising treatment in recurrent glioma

  3. The Design of a Prompt Gamma Neutron Activation Analysis Beam for BNCT Purpose at the TRIGA Mark II Reactor in Pavia

    Energy Technology Data Exchange (ETDEWEB)

    Stella, S.; Bazani, A.; Ballarini, F.; Bortolussi, S.; Protti, N.; Altieri, S. [Department of Nuclear and Theoretical Physics, University of Pavia (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Section of Pavia (Italy); Bruschi, P. [Department of Nuclear and Theoretical Physics, University of Pavia (Italy)

    2011-07-01

    In preclinical and clinical Boron Neutron Capture Therapy studies the knowledge of the amount of {sup 10}B in blood and tissues is very important. The boron concentration measurements method used in Pavia (Italy) is based on the charged particles spectrometry of thin tissue cuts irradiated in the Thermal Column of the TRIGA reactor of the University. In order to perform measurements in biological liquids such as blood and urine, or in other tissue that cannot be cut in slices, a Prompt Gamma Neutron Activation Analysis (PGNAA) facility is being designed, which measures {sup 10}B concentration detecting the prompt gamma from boron nuclear capture reaction. At the TRIGA reactor in Pavia, there are four horizontal channels, potentially available for PGNAA. The choice of the suitable channel, and the design of its configuration, were achieved using the Monte Carlo neutron transport code MCNP4c2. To perform the simulations, an input code already validated, describing the reactor structure and the neutron source, was used. The calculations were implemented applying non-analog techniques for the neutron transport, that are necessary to obtain a sufficient statistic in every positions along the channel and especially at its end. The selection of the channel for PGNAA installation was carried out by comparing the simulated fluxes obtained in the different channels at the present configuration. The channel shielded by the core reflector was chosen, because the graphite lowers the fast component of the neutrons, with no need to insert additional material in the facility. The thermal flux at its end is 1.7 x 10{sup 8} n/cm{sup 2} s with thermal-to-total neutron flux ratio around 0.8. Subsequently a bismuth block for gamma radiation shielding and blocks of single crystal sapphire as filter for fast neutron component were inserted in the channel. Other components of the facility that are under study are a collimator and the beam catcher. (author)

  4. Study on establishing an irradiator for neutron dose calibration

    International Nuclear Information System (INIS)

    The objective of the theme is to establish an irradiator for neutron dose calibration. To realize the objective, authors used the MCNP4C2 code to have a optimal configuration of the irradiator. Then the MCNP4C2 code was used for calculation of neutron dose rates and average energies at 03 irradiation positions with different thicknesses of a PMMA block. At last, 21 dose rate values in the range 1 - 82 [μSv/h] and 07 different neutron spectra with average energies in the range 0.8 - 2.1 MeV were received. In addition, the calculated values were compared with values received by using a neutron dose rate meter ALOKA (Japan). It showed that at distances about 1.50 m or more from the neutron sources and neutron spectra having average energies less than 1.80 MeV, the differences between the calculated and measured values were less than 5 %. It means that calculated results are good and the facility could be used for calibrating neutron dose rate meters and dosimeters. (author)

  5. Boron Neutron Capture Therapy at European research reactors - Status and perspectives

    International Nuclear Information System (INIS)

    Over the last decade. there has been a significant revival in the development of Boron Neutron Capture Therapy (BNCT) as a treatment modality for curing cancerous tumours, especially glioblastoma multiforme and subcutaneous malignant melanoma. In 1987 a European Collaboration on BNCT was formed, with the prime task to identify suitable research reactors in Europe where BNCT could be applied. Due to reasons discussed in this paper, the HFR Petten was chosen as the test-bed for demonstrating BNCT. Currently, the European Collaboration is approaching the start of clinical trials, using epithermal neutrons and borocaptate sodium (BSH) as the 10B delivery agent. The treatment is planned to start in the first half of 1996. The paper here presents an overview on the principle of BNCT, the requirements imposed on a research reactor in order to be considered for BNCT, and the perspectives for other European materials testing reactors. A brief summary on the current status of the work at Petten is given, including: the design, construction and characterisation of the epithermal neutron beam: performance and results of the healthy tissue tolerance study; the development of a treatment planning programme based on the Monte Carlo code MCNP; the design of an irradiation room; and on the clinical trials themselves. (author)

  6. Quantitative evaluation of boron neutron capture therapy (BNCT) drugs for boron delivery and retention at subcellular scale resolution in human glioblastoma cells with imaging secondary ion mass spectrometry (SIMS)

    Science.gov (United States)

    Chandra, S.; Ahmad, T.; Barth, R. F.; Kabalka, G. W.

    2014-01-01

    Boron neutron capture therapy (BNCT) of cancer depends on the selective delivery of a sufficient number of boron-10 (10B) atoms to individual tumor cells. Cell killing results from the 10B (n, α)7Li neutron capture and fission reactions that occur if a sufficient number of 10B atoms are localized in the tumor cells. Intranuclear 10B localization enhances the efficiency of cell killing via damage to the DNA. The net cellular content of 10B atoms reflects both bound and free pools of boron in individual tumor cells. The assessment of these pools, delivered by a boron delivery agent, currently cannot be made at subcellular scale resolution by clinically applicable techniques such as PET and MRI. In this study, secondary ion mass spectrometry (SIMS) based imaging instrument, a CAMECA IMS 3f ion microscope, capable of 500 nm spatial resolution was employed. Cryogenically prepared cultured human T98G glioblastoma cells were evaluated for boron uptake and retention of two delivery agents. The first, L-p-boronophenylalanine (BPA), has been used clinically for BNCT of high grade gliomas, recurrent tumors of the head and neck region and melanomas. The second, a boron analogue of an unnatural amino acid, 1-amino-3-borono-cyclopentanecarboxylic acid (cis-ABCPC), has been studied in rodent glioma and melanoma models by quantification of boron in the nucleus and cytoplasm of individual tumor cells. The bound and free pools of boron were assessed by exposure of cells to boron-free nutrient medium. Both BPA and cis-ABCPC delivered almost 70% of the pool of boron in the free or loosely bound form to the nucleus and cytoplasm of human glioblastoma cells. This free pool of boron could be easily mobilized out of the cell and was in some sort of equilibrium with extracellular boron. In the case of BPA, the intracellular free pool of boron also was affected by the presence of phenylalanine in the nutrient medium. This suggests that it might be advantageous if patients were placed on a

  7. INEL BNCT Research Program annual report 1994

    Energy Technology Data Exchange (ETDEWEB)

    Venhuizen, J.R. [ed.

    1995-11-01

    This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1994. Contributions from the principal investigators about their individual projects are included, specifically, chemistry (pituitary tumor studies, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, ICP-AES analysis of biological samples), physics (treatment planning software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (small and large animal models tissue studies and efficacy studies). Information on the potential toxicity of BSH and BPA is presented and results of 21 spontaneous tumor bearing dogs that have been treated with BNCT at Brookhaven National Laboratory (BNL) are discussed. Several boron carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors is presented. Highlights from the First International Workshop on Accelerator-Based Neutron Sources for BNCT are included. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  8. Current clinical results of the Tsukuba BNCT trial

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, T.; Matsumura, A. E-mail: matsumur@md.tsukuba.ac.jp; Nakai, K.; Shibata, Y.; Endo, K.; Sakurai, F.; Kishi, T.; Kumada, H.; Yamamoto, K.; Torii, Y

    2004-11-01

    Nine high grade gliomas (5 glioblastomas and 4 anaplastic astrocytomas) were treated with BSH-based intaoperative boron neutron capture therapy (IOBNCT). BSH (100 mg/kg body weight) was intravenously injected, followed by single fraction irradiation using the mixed thermal/epithermal beam of Japan Research Reactor 4. The blood boron level at the time of irradiation averaged 29.9 (18.8-39.5) {mu}g/g. The peak thermal neutron flux as determined by post-irradiation measurements varied from 1.99 to 2.77x10{sup 9} n cm{sup -2} s{sup -1}. No serious BSH-related toxicity was observed in this series. The interim survival data in this study showed median survival times of 23.2 months for glioblastoma and 25.9 months for anaplastic astrocytoma, results which are consistent with the current conventional radiotherapy with/without boost radiation. Of the 4 residual tumors, 2 showed complete response (CR) and 2 showed partial response (PR) within 6 months following BNCT. No linear correlation was proved between the dose and the occurrence of early neurological events. The maximum boron dose of 11.7-12.2 Gy in the brain related to the occurrence of radiation necrosis. The clinical application of a mixed thermal/epithermal beam and JRR-4 facilities on BSH-based IOBNCT proved to be safe and effective in this series.

  9. Boron neutron capture therapy induces apoptosis of glioma cells through Bcl-2/Bax

    Directory of Open Access Journals (Sweden)

    Mao Xinggang

    2010-12-01

    Full Text Available Abstract Background Boron neutron capture therapy (BNCT is an alternative treatment modality for patients with glioma. The aim of this study was to determine whether induction of apoptosis contributes to the main therapeutic efficacy of BNCT and to compare the relative biological effect (RBE of BNCT, γ-ray and reactor neutron irradiation. Methods The neutron beam was obtained from the Xi'an Pulsed Reactor (XAPR and γ-rays were obtained from [60Co] γ source of the Fourth Military Medical University (FMMU in China. Human glioma cells (the U87, U251, and SHG44 cell lines were irradiated by neutron beams at the XAPR or [60Co] γ-rays at the FMMU with different protocols: Group A included control nonirradiated cells; Group B included cells treated with 4 Gy of [60Co] γ-rays; Group C included cells treated with 8 Gy of [60Co] γ-rays; Group D included cells treated with 4 Gy BPA (p-borono-phenylalanine-BNCT; Group E included cells treated with 8 Gy BPA-BNCT; Group F included cells irradiated in the reactor for the same treatment period as used for Group D; Group G included cells irradiated in the reactor for the same treatment period as used for Group E; Group H included cells irradiated with 4 Gy in the reactor; and Group I included cells irradiated with 8 Gy in the reactor. Cell survival was determined using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium (MTT cytotoxicity assay. The morphology of cells was detected by Hoechst33342 staining and transmission electron microscope (TEM. The apoptosis rate was detected by flow cytometer (FCM. The level of Bcl-2 and Bax protein was measured by western blot analysis. Results Proliferation of U87, U251, and SHG44 cells was much more strongly inhibited by BPA-BNCT than by irradiation with [60Co] γ-rays (P 60Co] γ-rays (P P Conclusions Compared with ��-ray and reactor neutron irradiation, a higher RBE can be achieved upon treatment of glioma cells with BNCT. Glioma cell apoptosis induced by

  10. Neutron irradiation influence on magnesium aluminium spinel inversion

    Science.gov (United States)

    Skvortsova, V.; Mironova-Ulmane, N.; Ulmanis, U.

    2002-05-01

    Grown by the Verneuil method MgO · nAl 2O 3 single crystals and natural spinel crystal have been studied using X-ray diffraction and photoluminescence spectra. The fast neutron irradiation of magnesium aluminium spinel leads to the lattice parameter decrease. The bond lengths of Mg-O and Al-O vary with the u-parameter and the lattice parameter. On the other hand, the bond lengths are related with the inversion parameter. Using changes of the lattice parameter during irradiation we have calculated the inversion parameter, which is 15-20%. In the luminescence spectra, the fast neutron radiation (fluence 10 16 cm -2) produces an increase in the intensity ratio of the N- to R-lines by 5-20%. Taking into account that intensity of the N-lines is closely associated with the inversion parameter, it is possible to state that the neutron irradiation causes the increasing of the spinel inversion.

  11. Neutron irradiation influence on magnesium aluminium spinel inversion

    International Nuclear Information System (INIS)

    Grown by the Verneuil method MgO · nAl2O3 single crystals and natural spinel crystal have been studied using X-ray diffraction and photoluminescence spectra. The fast neutron irradiation of magnesium aluminium spinel leads to the lattice parameter decrease. The bond lengths of Mg-O and Al-O vary with the u-parameter and the lattice parameter. On the other hand, the bond lengths are related with the inversion parameter. Using changes of the lattice parameter during irradiation we have calculated the inversion parameter, which is 15-20%. In the luminescence spectra, the fast neutron radiation (fluence 1016 cm-2) produces an increase in the intensity ratio of the N- to R-lines by 5-20%. Taking into account that intensity of the N-lines is closely associated with the inversion parameter, it is possible to state that the neutron irradiation causes the increasing of the spinel inversion

  12. Cation disorder in high dose neutron irradiated spinel

    International Nuclear Information System (INIS)

    The crystal structures of MgAl2O4 spinel single crystals irradiated to high neutron fluences (>5·1026 n/m2 (En>0.1 MeV)), were examined by neutron diffraction. Crystal structure refinement of the highest dose sample indicated that the average scattering strength of the tetrahedral crystal sites decreased by ∼20% while increasing by ∼8% on octahedral sites. Since the neutron scattering length for Mg is considerably larger than for Al, this result is consistent with site exchange between Mg2+ ions on tetrahedral sites and Al3+ ions on octahedral sites. Least squares refinements also indicated that in all irradiated samples, at least 35% of Mg2+ and Al3+ ions in the crystal experienced disordering replacements. This retained dpa on the cation sublattices is the largest retained damage ever measured in an irradiated spinel material

  13. Some recent developments in treatment planning software and methodology for BNCT

    International Nuclear Information System (INIS)

    Over the past several years/the Idaho National Engineering Laboratory (INEL) has led the development of a unique, internationally-recognized set of software modules (BNCT rtpe) for computational dosimetry and treatment planning for Boron Neutron Capture Therapy (BNCT). The computational capability represented by this software is essential to the proper administration of all forms of radiotherapy for cancer. Such software addresses the need to perform pretreatment computation and optimization of the radiation dose distribution in the target volume. This permits the achievement of the optimal therapeutic ratio (tumor dose relative to critical normal tissue dose) for each individual patient via a systematic procedure for specifying the appropriate irradiation parameters to be employed for a given treatment. These parameters include angle of therapy beam incidence, beam aperture and shape,and beam intensity as a function of position across the beam front. The INEL software is used for treatment planning in the current series of human glioma trials at Brookhaven National Laboratory (BNL) and has also been licensed for research and developmental purposes to several other BNCT research centers in the US and in Europe

  14. Calculation of neutron flux and spectrum in the irradiation test capsule at HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Seong Woo; Cho, Man Soon; Choo, Kee Nam; Park, Sang Jun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    The irradiation test capsules were mostly used for the irradiation test in CT and OR5 irradiation hole. Since the neutron fluence is an important factor, fluence monitor(F/M)s were inserted in the irradiation test capsule in order to measure the neutron fluence of test specimen. Not only the good measurement technique but also the calculation data is necessary to accurately evaluate the neutron fluence of irradiated material. Therefore, following factors should be calculated for detailed evaluation of the neutron fluence; Neutron flux and spectrum with the position of control absorber rod(CAR), Neutron flux and spectrum at the candidate F/M irradiated position, Neutron fluence difference between F/M and specimen From this calculation data, the neutron fluence of irradiated specimen and F/M can be predicted. In this paper, the neutron flux and spectrum were calculated for the irradiation capsule. This data can be a basic data of neutron dosimetry for the irradiation test and applied to select the optimum F/M installation position and verify the neutron fluence of the specimen. The neutron flux and spectrum was calculated for irradiation test capsule. The difference of neutron flux and spectrum of the irradiation test capsule in CT and OR5 irradiation hole was observed. Also the spectral averaged cross section was calculated and applied to the fast neutron fluence evaluation. As a result of this evaluation, the good agreement between calculated and measured data was shown.

  15. Treatment of malignant brain tumors using nuclear reactor. Neutron capture therapy

    International Nuclear Information System (INIS)

    Principles, history, clinical trial experiences and future view of the neutron capture therapy are described. The therapy using 10B (boron neutron capture therapy, BNCT) involves the intravenous injection of 10B-containing compound to be accumulated in the tumor and following irradiation of thermal (10B-containing compound, of multi-gated and boost irradiation, of accelerator exclusively for the therapy and of systemic facility for the therapy are waited. (K.H.)

  16. Optimization of the BNCT filter

    International Nuclear Information System (INIS)

    The Czech Boron Neutron Capture Therapy (BNCT) facility works by an epithermal neutron beam installed at the LVR-15 reactor at Rez near Prague. Several configurations of moderating and shielding materials have been designed in order to ensure appropriate parameters of the beam. The beam filter consists of cylindrical layers of Al, AlF3 and Ti. To decrease the gamma two layers of Pb are implemented. The filter geometry and composition has been optimized with the aim to increase the epithermal neutron fluence rate and decrease the fast neutron dose rate using the MCNP-4B Monte Carlo code with the DLC-189 library. Suitable patterns of the reactor core were also studied especially in regard to a possible installation of fuel units close to the filter input. Results of calculations show that the optimized variant of the reactor core is able to increase the intensity of the fast neutron source incident to the filter by a factor of 2.0. An experimental verification of the beam parameters was performed using different measurement techniques. The neutron energy spectrum was measured with a set of activation foils, by a Bonner spheres spectrometer and a fast neutron spectrometer with a stilbene crystal. The fast neutron kerma rate was calculated from the spectral measurement. Al-P TLD were used to measure the photon absorbed dose. The beam parameters were measured at 10 MW and were found as follows: the epithermal neutron fluence rate (an energy range from 1 eV to 10 keV) of 9.29 x 1012 m-2 s-1, the fast neutron kerma rate in tissue of 2.63 Gy h-1 and the incident gamma dose rate in tissue of 29 Gy h-1. (author)

  17. Changes in graphite porous structure under neutron irradiation

    International Nuclear Information System (INIS)

    Reactor graphite porous structure is investigated using methods of mercury porosimetry, X-ray low-angle scattering and X-ray analysis. Change of porous structure under the effect of neutron fluence up to 1.3x1022 neutr/cm2 at the temperature of 360-1100 K is described. It is shown that long-term neutron irradiation causes irreversible changes in reactor graphite porous structure at its different levels

  18. Irradiation facilities at the spallation neutron source SINQ

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, E.; Ledermann, J.; Aebersold, H.; Kuehne, G.; Kohlik, K. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    Four independent experiments for sample irradiation are under construction and in preparation for operational tests at the spallation source SINQ. Three of them are located inside a thermal beam port with end positions inside or near the moderator tank. The other experiment will be established at the end position of a super mirror lined neutron guide for applications with cold neutrons. (author) 3 figs., 1 tab., 6 refs.

  19. Design of neutron beams for boron neutron capture therapy in a fast reactor

    International Nuclear Information System (INIS)

    The BNCT (Boron Neutron Capture Therapy) technique makes use of thermal or epithermal neutrons to irradiate tumours previously loaded with 10B. Reactors are currently seen as a suitable neutron source for BNCT implementation, due to the high intensity of the flux they can provide. The TAPIRO reactor, that is located at the ENEA Casaccia Centre near Rome, is a low-power fast-flux research reactor that can be usefully employed for this application. In this work computer simulations were carried out on this reactor to obtain epithermal and thermal neutron beams for the application of BNCT in Italy in the framework of a specific research program. Comparisons with measurements are also reported. Using the MCNP-4B code, Monte Carlo calculations were carried out to determine the materials suitable for the design of the thermal and epithermal columns. Various arrangements of reflector and moderator materials have been investigated to achieve the desired experimental constraints. On the basis of these calculations, a thermal column was designed and installed in the TAPIRO reactor to perform preliminary experiments on small laboratory animals. For the planning of a therapy treatment of gliomas on larger size animals, several material configurations were investigated in the search for an optimal epithermal facility. The aim of the present study is to indicate how a fast research reactor can be successfully modified for generating neutron beams suitable for BNCT applications. (author)

  20. Neutron irradiation effect of thermally-sensitized stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Hide, Kouitiro [Central Research Inst. of Electric Power Industry, Komae, Tokyo (Japan). Komae Research Lab.

    1998-03-01

    Intergranular stress corrosion cracking (IGSCC) susceptibility of irradiated thermally-sensitized Type 304 Stainless Steels (SSs) was studied as a function of neutron fluence and correlated with mechanical responses of the materials. Neutron irradiation was carried out to neutron fluences up to 1.1 x 10{sup 24} n/m{sup 2} (E > 1MeV) at the light water reactor temperature in the Japan Material Test Reactor. The irradiated specimens were examined by slow strain rate stress corrosion cracking tests in 290degC pure water of 0.2 ppm dissolved oxygen concentration and microhardness measurements. The IGSCC susceptibility of the irradiated specimens increased with neutron fluence up to 1.1 x 10{sup 24} n/m{sup 2}. From an attempt to correlate the IGSCC susceptibility with the mechanical properties, an excellent correlation was identified between the susceptibility and microhardness increments at the grain boundary relative to the grain center. While intergranular corrosion rate of thermally sensitized SS increased with neutron fluence up to 1.1 x 10{sup 24} n/m{sup 2}, that of solution annealed SS did not change. The incremental grain boundary hardening and degradation of intergranular corrosion resistance may presumably be the major factors affecting IGSCC performance. (author)

  1. Behavior of fluorine 18 in neutron irradiated zeolites

    International Nuclear Information System (INIS)

    The transformation of Li-exchanged H-Y zeolite has been investigated at 300, 550, 850 and 1050 Centigrade degree, formation of quartz structure in addition to an amorphous phase, was nited. The Li-aluminosilicate obtained was neutron irradiated and the chemical behavior of 18F produced by the reaction sequence 6Li (n, α) 3H, 16O (3H, n) 18F, was studied. The neutron irradiated material was purged with argon-hydron gas streams. It was found that the amount of released 18F depends on the temperature used (Author)

  2. Microstructure and mechanical properties of neutron irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Ishitsuka, E.; Kawamura, H. [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Terai, T.; Tanaka, S.

    1998-01-01

    Microstructure and mechanical properties of the neutron irradiated beryllium with total fast neutron fluences of 1.3 - 4.3 x 10{sup 21} n/cm{sup 2} (E>1 MeV) at 327 - 616degC were studied. Swelling increased by high irradiation temperature, high fluence, and by the small grain size and high impurity. Obvious decreasing of the fracture stress was observed in the bending test and in small grain specimens which had many helium bubbles on the grain boundary. Decreasing of the fracture stress for small grain specimens was presumably caused by crack propagation on the grain boundaries which weekend by helium bubbles. (author)

  3. A state-of-the-art epithermal neutron irradiation facility for neutron capture therapy

    International Nuclear Information System (INIS)

    At the Massachusetts Institute of Technology (MIT) the first fission converter-based epithermal neutron beam (FCB) has proven suitable for use in clinical trials of boron neutron capture therapy (BNCT). The modern facility provides a high intensity beam together with low levels of contamination that is ideally suited for use with future, more selective boron delivery agents. Prescriptions for normal tissue tolerance doses consist of 2 or 3 fields lasting less than 10 min each with the currently available beam intensity, that are administered with an automated beam monitoring and control system to help ensure safety of the patient and staff alike. A quality assurance program ensures proper functioning of all instrumentation and safety interlocks as well as constancy of beam output relative to routine calibrations. Beam line shutters and the medical room walls provide sufficient shielding to enable access and use of the facility without affecting other experiments or normal operation of the multipurpose research reactor at MIT. Medical expertise and a large population in the greater Boston area are situated conveniently close to the university, which operates the research reactor 24 h a day for approximately 300 days per year. The operational characteristics of the facility closely match those established for conventional radiotherapy, which together with a near optimum beam performance ensure that the FCB is capable of determining whether the radiobiological promise of NCT can be realized in routine practice

  4. First results of laser welding of neutron irradiated stainless steel

    International Nuclear Information System (INIS)

    First results of experimental investigations on the laser reweldability of neutron irradiated material are reported. These experiments include the manufacture of 'heterogeneous' joints, which means joining of irradiated stainless steel of type AISI 316L-SPH to 'fresh' unirradiated material. The newly developed laser welding facility in the ECN Hot Cell Laboratory and experimental procedures are described. Visual inspections of welded joints are reported as well as results of electron microscopy and preliminary metallographic examinations. (orig.)

  5. The boron neutron capture therapy facility of the ETRR-2: a promising opportunity for cancer research and treatment

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a binary modality that can selectively irradiate tumor tissue using drugs containing 10B that are capable of preferntially accumulating in the tumor, which is then irradiated with thermal neutrins. This casuses the 10B nucleus to split, releasing an alpha particle and a lithium nucleus. These products are very damaging to cells but have ranges of the order of cell diameters. The technique is minly used for the treatment of Glioblastoma, a highly malignant tumor whose treatment is not statisfactory using conventional techniques. Other types of cancer, like melanoma, are also considered. Since early nineties, the area of BNCT is witnessing active developments in the USA, Japan, and Europe. the Egyptian second experimental and training research reactor (ETRR-2) is a pool-type MPR. It has four neutron beam and a thermal column as the main experimental devices. One of the main reactor facilities is the BNCT unit. The paper highlights the basics of the BNCT, its development, and status around the world. A brief description of the reactor, the BNCt uint as well as the preliminary analysis done for the facility is presented. The BNCT offers a unique opportunity for coordinated efforts by the arab nuclear organizations and medical institutions similar to the on going efforts at Petten, the netherlands

  6. INEEL BNCT research program. Annual report, January 1, 1996--December 31, 1996

    International Nuclear Information System (INIS)

    This report is a summary of the progress and research produced for the Idaho National Engineering and Environmental Laboratory (INEEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1996. Contributions from the individual investigators about their projects are included, specifically, physics: treatment planning software, real-time neutron beam measurement dosimetry, measurement of the Finnish research reactor epithermal neutron spectrum, BNCT accelerator technology; and chemistry: analysis of biological samples and preparation of 10B enriched decaborane

  7. Structural properties and neutron irradiation effects of ceramics

    International Nuclear Information System (INIS)

    In high temperature gas-cooled reactors and nuclear fusion reactors being developed at present, various ceramics are to be used in the environment of neutron irradiation for undertaking important functions. The change of the characteristics of those materials by neutron irradiation must be exactly forecast, but it has been known that the response of the materials is different respectively. The production method of ceramics and the resulted structures of ceramics which control their characteristics are explained. The features of covalent bond and ionic bond, the synthesis of powder and the phase change by heating, sintering and sintering agent, and grain boundary phase are described. The smelling of ceramics by neutron irradiation is caused by the formation of the clusters of Frenkel defects and minute spot defects. Its restoration by annealing is explained. The defects remaining in materials after irradiation are the physical defects by flipping atoms cut due to the collision with high energy particles and the chemical defects by nuclear transformation. Some physical defects can be restored, but chemical defects are never restored. The mechanical properties of ceramics and the effect of irradiation on them, and the thermal properties of ceramics and the effect of irradiation on them are reported. (K.I.)

  8. Neutron irradiation creep in stainless steel alloys

    Energy Technology Data Exchange (ETDEWEB)

    Schuele, Wolfgang (Commission of the European Union, Institute for Advanced Materials, I-21020 Ispra (Vatican City State, Holy See) (Italy)); Hausen, Hermann (Commission of the European Union, Institute for Advanced Materials, I-21020 Ispra (Vatican City State, Holy See) (Italy))

    1994-09-01

    Irradiation creep elongations were measured in the HFR at Petten on AMCR steels, on 316 CE-reference steels, and on US-316 and US-PCA steels varying the irradiation temperature between 300 C and 500 C and the stress between 25 and 300 MPa. At the beginning of an irradiation a type of primary'' creep stage is observed for doses up to 3-5 dpa after which dose the secondary'' creep stage begins. The primary'' creep strain decreases in cold-worked steel materials with decreasing stress and decreasing irradiation temperature achieving also negative creep strains depending also on the pre-treatment of the materials. These primary'' creep strains are mainly attributed to volume changes due to the formation of radiation-induced phases, e.g. to the formation of [alpha]-ferrite below about 400 C and of carbides below about 700 C, and not to irradiation creep. The secondary'' creep stage is found for doses larger than 3 to 5 dpa and is attributed mainly to irradiation creep. The irradiation creep rate is almost independent of the irradiation temperature (Q[sub irr]=0.132 eV) and linearly dependent on the stress. The total creep elongations normalized to about 8 dpa are equal for almost every type of steel irradiated in the HFR at Petten or in ORR or in EBR II. The negative creep elongations are more pronounced in PCA- and in AMCR-steels and for this reason the total creep elongation is slightly smaller at 8 dpa for these two steels than for the other steels. ((orig.))

  9. Neutron irradiation creep in stainless steel alloys

    Science.gov (United States)

    Schüle, Wolfgang; Hausen, Hermann

    1994-09-01

    Irradiation creep elongations were measured in the HFR at Petten on AMCR steels, on 316 CE-reference steels, and on US-316 and US-PCA steels varying the irradiation temperature between 300°C and 500°C and the stress between 25 and 300 MPa. At the beginning of an irradiation a type of "primary" creep stage is observed for doses up to 3-5 dpa after which dose the "secondary" creep stage begins. The "primary" creep strain decreases in cold-worked steel materials with decreasing stress and decreasing irradiation temperature achieving also negative creep strains depending also on the pre-treatment of the materials. These "primary" creep strains are mainly attributed to volume changes due to the formation of radiation-induced phases, e.g. to the formation of α-ferrite below about 400°C and of carbides below about 700°C, and not to irradiation creep. The "secondary" creep stage is found for doses larger than 3 to 5 dpa and is attributed mainly to irradiation creep. The irradiation creep rate is almost independent of the irradiation temperature ( Qirr = 0.132 eV) and linearly dependent on the stress. The total creep elongations normalized to about 8 dpa are equal for almost every type of steel irradiated in the HFR at Petten or in ORR or in EBR II. The negative creep elongations are more pronounced in PCA- and in AMCR-steels and for this reason the total creep elongation is slightly smaller at 8 dpa for these two steels than for the other steels.

  10. Neutron irradiation creep in stainless steel alloys

    International Nuclear Information System (INIS)

    Irradiation creep elongations were measured in the HFR at Petten on AMCR steels, on 316 CE-reference steels, and on US-316 and US-PCA steels varying the irradiation temperature between 300 C and 500 C and the stress between 25 and 300 MPa. At the beginning of an irradiation a type of ''primary'' creep stage is observed for doses up to 3-5 dpa after which dose the ''secondary'' creep stage begins. The ''primary'' creep strain decreases in cold-worked steel materials with decreasing stress and decreasing irradiation temperature achieving also negative creep strains depending also on the pre-treatment of the materials. These ''primary'' creep strains are mainly attributed to volume changes due to the formation of radiation-induced phases, e.g. to the formation of α-ferrite below about 400 C and of carbides below about 700 C, and not to irradiation creep. The ''secondary'' creep stage is found for doses larger than 3 to 5 dpa and is attributed mainly to irradiation creep. The irradiation creep rate is almost independent of the irradiation temperature (Qirr=0.132 eV) and linearly dependent on the stress. The total creep elongations normalized to about 8 dpa are equal for almost every type of steel irradiated in the HFR at Petten or in ORR or in EBR II. The negative creep elongations are more pronounced in PCA- and in AMCR-steels and for this reason the total creep elongation is slightly smaller at 8 dpa for these two steels than for the other steels. ((orig.))

  11. A constitutive equation of irradiation creep and swelling under neutron irradiation

    International Nuclear Information System (INIS)

    A constitutive equation of irradiation creep for irradiated materials applicable to structural analyses in a multiaxial state of stress was developed. After reviewing microscopic mechanisms of irradiation creep and swelling, the relevant theories proposed from the view point of metallurgical physics and their applicability were discussed first. Then a constitutive model was developed by assuming that irradiation creep can be decomposed into irradiation-enhanced creep and irradiation-induced creep. By taking account of the SIPA (Stress Induced Preferential Absorption) mechanism, the irradiation-induced creep was represented by an isotropic tensor function of order one and zero with respect to stress, which is, at the same time, the function of neutron flux and neutron fluence. The volumetric part of the irradiation-induced creep was identified with swelling. The irradiation-enhanced creep was described by modifying Kachanov-Rabotnov creep damage theory by incorporating the effect of irradiation. Finally the irradiation creep and swelling of type 316 stainless steel at elevated temperatures were predicted by the proposed constitutive equation, and the numerical results were compared with the corresponding experimental results. (author)

  12. The therapeutic ratio in BNCT: Assessment using the Rat 9L gliosarcoma brain tumor and spinal cord models

    International Nuclear Information System (INIS)

    During any radiation therapy, the therapeutic tumor dose is limited by the tolerance of the surrounding normal tissue within the treatment volume. The short ranges of the products of the 10B(n,α)7Li reaction produced during boron neutron capture therapy (BNCT) present an opportunity to increase the therapeutic ratio (tumor dose/normal tissue dose) to levels unprecedented in photon radiotherapy. The mixed radiation field produced during BNCT comprises radiations with different linear energy transfer (LET) and different relative biological effectiveness (RBE). The short ranges of the two high-LET products of the 'B(n,a)'Li reaction make the microdistribution of the boron relative to target cell nuclei of particular importance. Due to the tissue specific distribution of different boron compounds, the term RBE is inappropriate in defining the biological effectiveness of the 10B(n,α)7Li reaction. To distinguish these differences from true RBEs we have used the term open-quotes compound biological effectivenessclose quotes (CBE) factor. The latter can be defined as the product of the true, geometry-independent, RBE for these particles times a open-quotes boron localization factorclose quotes, which will most likely be different for each particular boron compound. To express the total BNCT dose in a common unit, and to compare BNCT doses with the effects of conventional photon irradiation, multiplicative factors (RBEs and CBEs) are applied to the physical absorbed radiation doses from each high-LET component. The total effective BNCT dose is then expressed as the sum of RBE-corrected physical absorbed doses with the unit Gray-equivalent (Gy-Eq)

  13. The therapeutic ratio in BNCT: Assessment using the Rat 9L gliosarcoma brain tumor and spinal cord models

    Energy Technology Data Exchange (ETDEWEB)

    Coderre, J.A.; Micca, P.L.; Nawrocky, M.M.; Fisher, C.D.; Bywaters, A. [Brookhaven National Lab., Upton, NY (United States); Morris, G.M.; Hopewell, J.W. [Univ. of Oxford (United Kingdom). CRC Normal Tissue Radiobiological Research Group

    1996-10-01

    During any radiation therapy, the therapeutic tumor dose is limited by the tolerance of the surrounding normal tissue within the treatment volume. The short ranges of the products of the {sup 10}B(n,{alpha}){sup 7}Li reaction produced during boron neutron capture therapy (BNCT) present an opportunity to increase the therapeutic ratio (tumor dose/normal tissue dose) to levels unprecedented in photon radiotherapy. The mixed radiation field produced during BNCT comprises radiations with different linear energy transfer (LET) and different relative biological effectiveness (RBE). The short ranges of the two high-LET products of the `B(n,a)`Li reaction make the microdistribution of the boron relative to target cell nuclei of particular importance. Due to the tissue specific distribution of different boron compounds, the term RBE is inappropriate in defining the biological effectiveness of the {sup 10}B(n,{alpha}){sup 7}Li reaction. To distinguish these differences from true RBEs we have used the term {open_quotes}compound biological effectiveness{close_quotes} (CBE) factor. The latter can be defined as the product of the true, geometry-independent, RBE for these particles times a {open_quotes}boron localization factor{close_quotes}, which will most likely be different for each particular boron compound. To express the total BNCT dose in a common unit, and to compare BNCT doses with the effects of conventional photon irradiation, multiplicative factors (RBEs and CBEs) are applied to the physical absorbed radiation doses from each high-LET component. The total effective BNCT dose is then expressed as the sum of RBE-corrected physical absorbed doses with the unit Gray-equivalent (Gy-Eq).

  14. Annealing behaviors of vacancy in varied neutron irradiated Czochralski silicon

    Institute of Scientific and Technical Information of China (English)

    CHEN Gui-feng; LI Yang-xian; LIU Li-li; NIU Ping-juan; NIU Sheng-li; CHEN Dong-feng

    2006-01-01

    The difference of annealing behaviors of vacancy-oxygen complex (VO) in varied dose neutron irradiated Czochralski silicon: (S1 5×1017 n/cm3 and S2 1.07×1019 n/cm3) were studied. The results show that the VO is one of the main defects formed in neutron irradiated Czochralski silicon (CZ-Si). In this defect,oxygen atom shares a vacancy,it is bonded to two silicon neighbors. Annealed at 200 ℃,divacancies are trapped by interstitial oxygen(Oi) to form V2O (840 cm-1). With the decrease of the 829 cm-1 (VO) three infrared absorption bands at 825 cm-1 (V2O2),834 cm-1 (V2O3) and 840 cm-1 (V2O) will rise after annealed at temperature range of 200-500 ℃. After annealed at 450-500 ℃ the main absorption bands in S1 sample are 834 cm-1,825 cm-1 and 889 cm-1 (VO2),in S2 is 825 cm-1. Annealing of A-center in varied neutron irradiated CZ-Si is suggested to consist of two processes. The first is due to trapping of VO by Oi in low dose neutron irradiated CZ-Si (S1) and the second is due to capture the wandering vacancy by VO,etc,in high dose neutron irradiated CZ-Si (S2),the VO2 plays an important role in the annealing of A-center. With the increase of the irradiation dose,the annealing behavior of A-center is changed.

  15. BNCT clinical trials of skin melanoma patients in Argentina

    International Nuclear Information System (INIS)

    The clinical outcome of six skin melanoma BNCT irradiations is presented. Three patients (A, B and C), with multiple subcutaneous skin metastases progressed to chemotherapy were infused with ∼14 g/m2 of boronophenylalanine (10BPA)-fructose and irradiated in the hyperthermal neutron beam of the RA-6 reactor. Patient A received two one fraction irradiations in different areas of the leg, B received one fraction and C was irradiated in three consecutive fields at the calf, heel and foot sole. The maximum prescribed dose to normal skin ranged from 16.5 to 24 Gy-Eq. With a minimum follow-up of 10 months there was a G1 acute epithelitis in A and B and a G3 in C. No late toxicity was observed. Due to the in-field tumor-growth-delay and the absence of severe acute and/or late toxicity observed during the follow-up period, a dose-escalation trial is ongoing. (author)

  16. High temperature neutron irradiation of carbon materials

    International Nuclear Information System (INIS)

    The radiation change in dimensions and certain properties of carbon structural materials, irradiated at 2100-2300 K by fluence up to 3x1020 neutr/cm2 (E >= 0.18 MeV) is considered. It is established that crystal structure of composite materials and carbon fibers improves as the result of high-temperature irradiation. The crystal lattice parameter decreases, whereas the dimensions of crystals and texture index grow

  17. Dosimetry in Thermal Neutron Irradiation Facility at BMRR

    Directory of Open Access Journals (Sweden)

    Hu J.-P.

    2016-01-01

    Full Text Available Radiation dosimetry for Neutron Capture Therapy (NCT has been performed since 1959 at Thermal Neutron Irradiation Facility (TNIF of the three-megawatt light-water cooled Brookhaven Medical Research Reactor (BMRR. In the early 1990s when more effective drug carriers were developed for NCT, in which the eye melanoma and brain tumors in rats were irradiated in situ, extensive clinical trials of small animals began using a focused thermal neutron beam. To improve the dosimetry at irradiation facility, a series of innovative designs and major modifications made to enhance the beam intensity and to ease the experimental sampling at BMRR were performed; including (1 in-core fuel addition to increase source strength and balance flux of neutrons towards two ports, (2 out of core moderator remodeling, done by replacing thicker D2O tanks at graphite-shutter interfacial areas, to expedite neutron thermalization, (3 beam shutter upgrade to reduce strayed neutrons and gamma dose, (4 beam collimator redesign to optimize the beam flux versus dose for animal treatment, (5 beam port shielding installation around the shutter opening area (lithium-6 enriched polyester-resin in boxes, attached with polyethylene plates to reduce prompt gamma and fast neutron doses, (6 sample holder repositioning to optimize angle versus distance for a single organ or whole body irradiation, and (7 holder wall buildup with neutron reflector materials to increase dose and dose rate from scattered thermal neutrons. During the facility upgrade, reactor dosimetry was conducted using thermoluminescent dosimeters TLD for gamma dose estimate, using ion chambers to confirm fast neutron and gamma dose rate, and by the activation of gold-foils with and without cadmium-covers, for fast and thermal neutron flux determination. Based on the combined effect from the size and depth of tumor cells and the location and geometry of dosimeters, the measured flux from cadmium-difference method was 4–7

  18. Dosimetry in Thermal Neutron Irradiation Facility at BMRR

    Energy Technology Data Exchange (ETDEWEB)

    Hu, J. P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Holden, N. E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Reciniello, R. N.

    2014-05-23

    Radiation dosimetry for Neutron Capture Therapy (NCT) has been performed since 1959 at Thermal Neutron Irradiation Facility (TNIF) of the three-megawatt light-water cooled Brookhaven Medical Research Reactor (BMRR). In the early 1990s when more effective drug carriers were developed for NCT, in which the eye melanoma and brain tumors in rats were irradiated in situ, extensive clinical trials of small animals began using a focused thermal neutron beam. To improve the dosimetry at irradiation facility, a series of innovative designs and major modifications made to enhance the beam intensity and to ease the experimental sampling at BMRR were performed; including (1) in-core fuel addition to increase source strength and balance flux of neutrons towards two ports, (2) out of core moderator remodeling, done by replacing thicker D2O tanks at graphite-shutter interfacial areas, to expedite neutron thermalization, (3) beam shutter upgrade to reduce strayed neutrons and gamma dose, (4) beam collimator redesign to optimize the beam flux versus dose for animal treatment, (5) beam port shielding installation around the shutter opening area (lithium-6 enriched polyester-resin in boxes, attached with polyethylene plates) to reduce prompt gamma and fast neutron doses, (6) sample holder repositioning to optimize angle versus distance for a single organ or whole body irradiation, and (7) holder wall buildup with neutron reflector materials to increase dose and dose rate from scattered thermal neutrons. During the facility upgrade, reactor dosimetry was conducted using thermoluminescent dosimeters TLD for gamma dose estimate, using ion chambers to confirm fast neutron and gamma dose rate, and by the activation of gold-foils with and without cadmium-covers, for fast and thermal neutron flux determination. Based on the combined effect from the size and depth of tumor cells and the location and geometry of dosimeters, the measured flux from cadmium-difference method was 4 - 7

  19. Dosimetry in Thermal Neutron Irradiation Facility at BMRR

    Science.gov (United States)

    Hu, J.-P.; Holden, N. E.; Reciniello, R. N.

    2016-02-01

    Radiation dosimetry for Neutron Capture Therapy (NCT) has been performed since 1959 at Thermal Neutron Irradiation Facility (TNIF) of the three-megawatt light-water cooled Brookhaven Medical Research Reactor (BMRR). In the early 1990s when more effective drug carriers were developed for NCT, in which the eye melanoma and brain tumors in rats were irradiated in situ, extensive clinical trials of small animals began using a focused thermal neutron beam. To improve the dosimetry at irradiation facility, a series of innovative designs and major modifications made to enhance the beam intensity and to ease the experimental sampling at BMRR were performed; including (1) in-core fuel addition to increase source strength and balance flux of neutrons towards two ports, (2) out of core moderator remodeling, done by replacing thicker D2O tanks at graphite-shutter interfacial areas, to expedite neutron thermalization, (3) beam shutter upgrade to reduce strayed neutrons and gamma dose, (4) beam collimator redesign to optimize the beam flux versus dose for animal treatment, (5) beam port shielding installation around the shutter opening area (lithium-6 enriched polyester-resin in boxes, attached with polyethylene plates) to reduce prompt gamma and fast neutron doses, (6) sample holder repositioning to optimize angle versus distance for a single organ or whole body irradiation, and (7) holder wall buildup with neutron reflector materials to increase dose and dose rate from scattered thermal neutrons. During the facility upgrade, reactor dosimetry was conducted using thermoluminescent dosimeters TLD for gamma dose estimate, using ion chambers to confirm fast neutron and gamma dose rate, and by the activation of gold-foils with and without cadmium-covers, for fast and thermal neutron flux determination. Based on the combined effect from the size and depth of tumor cells and the location and geometry of dosimeters, the measured flux from cadmium-difference method was 4-7% lower than

  20. A phase-I clinical trial for cranial BNCT at Harvard-MIT

    International Nuclear Information System (INIS)

    Phase I trial designed to determine the maximum tolerable dose to normal tissue for cranial BNCT (Boron Neutron Capture Therapy) irradiations was recently completed at Harvard Medical School and MIT. Twenty-two subjects diagnosed with either glioblastoma multiforme or intracranial melanoma were treated between 1996 and 1999. Subjects received either one or two administrations of boronophenylalanine intravenously at doses between 250 and 350 mg/kg body weight, then exposed in one, two or three fields to epithermal neutrons at the MIT Research Reactor in one or two fractions. Over the course of the study, the maximum normal tissue dose target was increased from 8.8 to 14.2 RBE (Relative Biological Effectiveness) Gy in 10% increments. Subjects have been followed clinically and radiographically. Of those patients surviving beyond six months, no MRI (Magnetic Resonance Image) white-matter changes were observed and no long-term complications attributable to BNCT were evident. Tumor responses were observed, particularly with the melanoma subjects. With increasing doses, difficulties arose from long irradiation times (approximately 3 hours) and the emergence of acute reactions in the skin and mucosa. The trial was stopped in May 1999. Future trials will be initiated with the new high intensity, low background fission converter beam at MIT. (author)

  1. Neutron irradiation effect on thermomechanical properties of shape memory alloys

    International Nuclear Information System (INIS)

    Alloys of Ti-Ni, Ti-Ni-Pd, Fe-Mn-Si, Mn-Cu-Cr, Mn-Cu, Cu-Al-Mn, Cu-Al-Ni systems are investigated after irradiation in IVV-2M reactor at various temperatures with neutron fluence of 1019 - 1020 cm-2. The degradation of shape memory effect in titanium nickelide base alloys is revealed after irradiation. Mn-Cu and Mn-Cu-Cr alloys show the best results. Trends in shape memory alloy behaviour depending on irradiation temperature are found. A consideration is given to the possibility of using these alloys for components of power reactor control and protection systems

  2. Change of glassy carbon structure and characteristics under neutron irradiation

    International Nuclear Information System (INIS)

    Results of the investigation into samples of glassy carbon SU-1300, SU-2000 after irradiation in the BOR-60 reactor at 360 - 400 Deg C are presented. It is established that the effect of significant radiation compression of the glassy carbon under irradiation retains till neutron fluence 3.6 x 1026 m-2 (E > 0.18 MeV). It is shown that radiation shrinkage is produced by shrinkage of graphite-like beds and decrease of molecular porosity. Increasing temperature of glassy carbon preparation from 1300 to 2000 Deg C tends to decrease of graphitization of the material under irradiation

  3. Changes in properties of glass ceramics under neutron irradiation

    International Nuclear Information System (INIS)

    Changes in properties of glass ceramics are considered as in initial state so after additional heat treatment up to 3000 K during neutron irradiation in the temperature range of 400-430 to 700-800 K and with fluence up to 2.5x1020 n/cm2. It is shown that additional heat treatment diminishes radiation effects in glass ceramics

  4. Dislocation and void segregation in copper during neutron irradiation

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Leffers, Torben; Horsewell, Andy

    1986-01-01

    High-purity (99. 999%) and fully annealed copper specimens have been irradiated in the DR-3 reactor at Riso to doses of 1 multiplied by 10**2**2 and 5 multiplied by 10**2**2 neutrons (fast)m** minus **2(2 multiplied by 10** minus **3 dpa and 1 multiplied by 10** minus **2 dpa, respectively); the...

  5. Radiation Damages in Aluminum Alloy SAV-1 under Neutron Irradiation

    Science.gov (United States)

    Salikhbaev, Umar; Akhmedzhanov, Farkhad; Alikulov, Sherali; Baytelesov, Sapar; Boltabaev, Azizbek

    2016-05-01

    The aim of this work was to study the effect of neutron irradiation on the kinetics of radiation damages in the SAV-1 alloy, which belongs to the group of aluminum alloys of the ternary system Al-Mg-Si. For fast-neutron irradiation by different doses up to fluence 1019 cm-2 the SAV-1 samples were placed in one of the vertical channels of the research WWR type reactor (Tashkent). The temperature dependence of the electrical resistance of the alloy samples was investigated in the range 290 - 490 K by the four-compensation method with an error about 0.1%. The experimental results were shown that at all the temperatures the dependence of the SAV-1 alloy resistivity on neutron fluence was nonlinear. With increasing neutron fluence the deviation from linearity and the growth rate of resistivity with temperature becomes more appreciable. The observed dependences are explained by means of martensitic transformations and the radiation damages in the studied alloy under neutron irradiation. The mechanisms of radiation modification of the SAV-1 alloy structure are discussed.

  6. Effects of neutron irradiation on polycrystalline Mg11B2

    International Nuclear Information System (INIS)

    We studied the influence of the disorder introduced in polycrystalline MgB2 samples by neutron irradiation. To circumvent self-shielding effects due to the strong interaction between thermal neutrons and 10B we employed isotopically enriched 11B which contains 40 times less 10B than natural B. The comparison of electrical and structural properties of different series of samples irradiated in different neutron sources, also using Cd shields, allowed us to conclude that, despite the low 10B content, the main damage mechanisms are caused by thermal neutrons, whereas fast neutrons play a minor role. Irradiation leads to an improvement in both upper critical field and critical current density for an exposure level in the range 1-2x1018 cm-2. With increasing fluence the superconducting properties are depressed. An in-depth analysis of the critical field and current density behavior has been carried out to identify what scattering and pinning mechanisms come into play. Finally, the correlation between some characteristic lengths and the transition widths is analyzed

  7. Examination of Austenitic Steels Microstructure Change Induced Neutron Irradiation by Using of Neutron Scattering Methods

    International Nuclear Information System (INIS)

    Two cladding pin austenitic steels ChS68 and EK164 irradiated in the BN-600 reactor up to maximum dose ∼80 dpa were examined by methods: neutron diffraction; small angle neutron scattering; X ray and electron microscopy. The formation and growth of both dislocation loops and radiation voids, as well as formation of segregation profiles, second phase precipitates, and chemical composition changes in a crystalline matrix were revealed in the steels after irradiation. All these resulted in growth of micro deformations in the crystalline matrix and changes of texture of the cladding pin steels, which were fixed by neutron diffraction and X ray methods. Texture decreasing more clearly occurred after low irradiation temperature (370°C) then after higher temperature irradiation (520°C). Observing of small angle neutron scattering increasing with dose growth is probably caused in He-v voids nucleus and segregations formed along dislocations and grain boundaries. At the present time the nature of scattering centers were not uniquely established. It is connected with an insufficiently adequate calculation model of small angle neutron scattering. Therefore solving of this problem requires additional development of calculation models. On the whole the examination shows that neutron scattering methods are very effective for research radiation induced structure changes. (author)

  8. Boron imaging with a microstrip silicon detector for applications in BNCT

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy (BNCT) is a radiotherapic technique exploiting the α particles produced after the irradiation of the isotope 10 of boron with thermal neutrons in the capture reaction 10B(n,α)7Li. It is used to treat tumours that for their features (radioresistance, extension, localization near vital organs) cannot be treated through conventional photon-beams radiotherapy. One of the main limitations of this technique is the lack of specificity (i.e. the ability of localizing in tumour cells, saving the healthy tissues) of the compounds used to carry the 10B isotope in the organs to be treated. This work, developed in the framework of the INFN PhoNeS project, describes the possibility of boron imaging performed exploiting the neutrons photoproduced by a linac (the Clinac 2100C/D of the S. Anna Hospital Radiotherapy Unit in Como, Italy) and detecting the α s with a non-depleted microstrip silicon detector: the result is a 1D scan of the boron concentration. Several boron doped samples have been analysed, from solutions of H3BO3 (reaching a minimum detectable amount of 25 ng of 10B) to biological samples of urine containing BPA and BSH (the two molecules currently used for the clinical trials in BNCT) in order to build kinetic curves (showing the absolute 10B concentration as a function of time). Further measurements are under way to test the imaging system with 10BPA-Fructose complex perfused human lung samples.

  9. Evaluation of thermal neutron irradiation field using a cyclotron-based neutron source for alpha autoradiography

    International Nuclear Information System (INIS)

    It is important to measure the microdistribution of 10B in a cell to predict the cell-killing effect of new boron compounds in the field of boron neutron capture therapy. Alpha autoradiography has generally been used to detect the microdistribution of 10B in a cell. Although it has been performed using a reactor-based neutron source, the realization of an accelerator-based thermal neutron irradiation field is anticipated because of its easy installation at any location and stable operation. Therefore, we propose a method using a cyclotron-based epithermal neutron source in combination with a water phantom to produce a thermal neutron irradiation field for alpha autoradiography. This system can supply a uniform thermal neutron field with an intensity of 1.7×109 (cm−2 s−1) and an area of 40 mm in diameter. In this paper, we give an overview of our proposed system and describe a demonstration test using a mouse liver sample injected with 500 mg/kg of boronophenyl-alanine. - Highlights: • We developed a thermal neutron irradiation field using cyclotron based epithermal neutron source combination with a water phantom for alpha autoradiography. • The uniform thermal neutron irradiation field with an intensity of 1.7×109 (cm−2 s−1) with a size of 40 mm in diameter was obtained. • Demonstration test of alpha autoradiography using a liver sample with the injection of BPA was performed. • Boron image discriminated with the background event of protons was clearly shown by means of the particle identification

  10. The effects of boron neutron capture therapy on liver tumors and normal hepatocytes in mice

    International Nuclear Information System (INIS)

    To explore the feasibility of employing boron neutron capture therapy (BNCT) to treat liver tumors, the effects of BNCT were investigated by using liver tumor models and normal hepatocytes in mice. Liver tumor models in C3H mice were developed by intrasplenic injection of SCCVII tumor cells. After borocaptate sodium (BSH) and boronophenylalanine (BPA) administration, 10B concentrations were measured in tumors and liver and the liver was irradiated with thermal neutrons. The effects of BNCT on the tumor and normal hepatocytes were studied by using colony formation assay and micronucleus assay, respectively. To compare the effects of BSH-BNCT and BPA-BNCT, the compound biological effectiveness (CBE) factor was determined. The CBE factors for BSH on the tumor were 4.22 and 2.29 using D10 and D0 as endpoints, respectively. Those for BPA were 9.94 and 5.64. In the case of hepatocytes, the CBE factors for BSH and BPA were 0.94 and 4.25, respectively. Tumor-to-liver ratios of boron concentration following BSH and BPA administration were 0.3 and 2.8, respectively. Considering the accumulation ratios of 10B, the therapeutic gain factors for BSH and BPA were 0.7-1.3 and 3.8-6.6, respectively. Therefore, it may be feasible to treat liver tumors with BPA-BNCT. (author)

  11. Design of a γ-ray analysis system for determination of boron in a patient's head, during neutron irradiation

    International Nuclear Information System (INIS)

    Boron Neutron Capture Therapy (BNCT) is a new radiation therapy in which thermal neutron capture by 10B is used for the selective destruction of a cancer tumour. At the High Flux Reactor (HFR) in Petten, Netherlands, a therapy facility is built for the neutron irradiations. In first instance, patients with a brain tumour will be treated. The doses delivered to the tumour and to the healthy tissue depend on the thermal neutron fluence and on the boron concentrations in these regions. Yet, both concentrations change in time after the administration of the tumour-seeking boron compound. An accurate determination of the patient's dose requires the knowledge of these time dependent concentrations during the therapy. For this reason, a γ-ray telescope system, together with a reconstruction tool, are developed. Two HPGe-detectors measure the 478 keV prompt γ-rays which are emitted at the boron neutron capture reaction, in a large background of γ-rays and neutrons. By using the detectors in a telescope configuration, only γ-rays emitted by a small specific region are detected. The best shielding of the detectors is obtained by performing the measurements through a small hole in the iron roof. A reconstruction tool is developed to calculate absolute boron concentrations using the measured boron γ-ray detection rates. Besides the boron γ-rays, a large component of 2.2 MeV γ-rays emitted at thermal neutron capture in hydrogen is measured. Since the hydrogen distribution is almost homogeneous over the head, this component can serve as a measure of the total number of thermal neutrons in the observed volume. By using the hydrogen γ-line for normalisation of the boron concentration, the reconstruction tool eliminates the greater part of the influence of the inhomogeneity of the thermal neutron distribution. MCNP calculations are used as a tool for the optimisation of the detector configuration. Experiments on a head phantom with 5 ppm 10B in healthy tissue and 62 ppm in

  12. Material deterioration due to neutron irradiation

    International Nuclear Information System (INIS)

    IAEA CRP 3 was a major effort to develop and validate surveillance methodologies for irradiation embrittlement characterisation and it is hardly any more possible to carry out similar co-operative programmes due to resource limitations. The programme included material characterisation by tensile, Charpy-V and fracture toughness tests. The programme promoted considerably the acceptance of direct fracture toughness characterisation of the irradiated material condition. Specimen preparation by reconstitution technique is becoming a common expertise in many laboratories. The VTT practice has been widely validated in the current programme. However, no international or co-operative validation programmes have not yet been performed with irradiated material, where the technique has its unique value but where possibility of incorrect application is also evident. (orig.)

  13. Effect of neutron and gamma irradiation on magnetic bubble memories

    International Nuclear Information System (INIS)

    Many years of research preceeded the introduction of magnetic bubble memories (M.B.M.) into the memory components market. They are used as bulk storage memories principally for their non volatile characteristics under irradiation. A physical and technological description of MBM is given in the first part of the text together with the results of work on their vulnerability when subjected to irradiation. Permanent damage caused by neutrons and gamma radiation on thin magnetic layers is then studied. A theoretical analysis on the stability of bubbles based on the results of pulsed laser experiments is given. The stability of the information stored in a commercially available MBM subjected to neutron and gamma irradiation (MBM - TIB 203 of 92 kBits, Texas) is described in the last part of the text. The vulnerability thresholds determined for the MBM are too high for them to be used in a radioactive environment with an improved electronic control system

  14. A new NEDO research project towards hospital based accelerator BNCT using advanced DDS system

    International Nuclear Information System (INIS)

    A new national project of developing a hospital based accelerator for boron neutron capture therapy (BNCT) with advanced drug delivery system (DDS) has been started in 2005. In this paper, the outline of the new project will be introduced. The project includes two main topics: 1) a hospital based accelerator for BNCT will be developed by a research consortium of Universities and companies. A fixed field alternating gradient (FFAG) type of accelerator with internal target is planned. 2) New boronated DDS using different methods including porphyrins, virus envelope vector, and liposome are planned. BNCT may become a first line charged particle therapy if the hospital based accelerator become feasible due to broadening the opportunity to use the neutron source. Due to such clinical convenience, there will be also possibility to spread the indication of BNCT for the diseases (cancer and other diseases) which has not been the candidate for BNCT in the nuclear-reactor era. (author)

  15. INEL BNCT Research Program annual report, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Venhuizen, J.R. [ed.

    1993-05-01

    This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1992. Contributions from all the principal investigators about their individual projects are included, specifically, chemistry (pituitary tumor targeting compounds, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis of biological samples), physics (radiation dosimetry software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (small and large animal models tissue studies and efficacy studies). Information on the potential toxicity of borocaptate sodium and boronophenylalanine is presented, results of 21 spontaneous-tumor-bearing dogs that have been treated with BNCT at the Brookhaven National Laboratory (BNL) Medical Research Reactor (BMRR) are discussed, and predictions for an epithermal-neutron beam at the Georgia Tech Research Reactor (GTRR) are shown. Cellular-level boron detection and localization by secondary ion mass spectrometry, sputter-initiated resonance ionization spectroscopy, low atomization resonance ionization spectroscopy, and alpha track are presented. Boron detection by ICP-AES is discussed in detail. Several boron carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors with BNCT is presented. Measurement of the epithermal-neutron flux at BNL and comparison to predictions are shown. Calculations comparing the GTRR and BMRR epithermal-neutron beams are also presented. Individual progress reports described herein are separately abstracted and indexed for the database.

  16. INEL BNCT Research Program annual report, 1992

    International Nuclear Information System (INIS)

    This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1992. Contributions from all the principal investigators about their individual projects are included, specifically, chemistry (pituitary tumor targeting compounds, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis of biological samples), physics (radiation dosimetry software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (small and large animal models tissue studies and efficacy studies). Information on the potential toxicity of borocaptate sodium and boronophenylalanine is presented, results of 21 spontaneous-tumor-bearing dogs that have been treated with BNCT at the Brookhaven National Laboratory (BNL) Medical Research Reactor (BMRR) are discussed, and predictions for an epithermal-neutron beam at the Georgia Tech Research Reactor (GTRR) are shown. Cellular-level boron detection and localization by secondary ion mass spectrometry, sputter-initiated resonance ionization spectroscopy, low atomization resonance ionization spectroscopy, and alpha track are presented. Boron detection by ICP-AES is discussed in detail. Several boron carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors with BNCT is presented. Measurement of the epithermal-neutron flux at BNL and comparison to predictions are shown. Calculations comparing the GTRR and BMRR epithermal-neutron beams are also presented. Individual progress reports described herein are separately abstracted and indexed for the database

  17. Radioisotopes produced by neutron irradiation of food.

    Science.gov (United States)

    Albright, S; Seviour, R

    2016-04-01

    The use of neutrons for cargo interrogation has the potential to drastically improve threat detection. Previous research has focussed on the production of (24)Na, based on the isotopes produced in pharmaceuticals and medical devices. For both the total activity and the ingestion dose we show that a variety of isotopes contribute and that (24)Na is only dominant under certain conditions. The composition of the foods has a strong influence on the resulting activity and ingestion dose suggesting that the pharmaceuticals and medical devices considered initially are not a viable analogue for foodstuffs. There is an energy dependence to the isotopes produced due to the cross-sections of different reactions varying with neutron energy. We show that this results in different isotopes dominating the ingestion dose at different energies, which has not been considered in the previous literature. PMID:26749562

  18. Improvements at the biological shielding of BNCT research facility in the IEA-R1 reactor

    International Nuclear Information System (INIS)

    The technique of neutron capture in boron is a promising technique in cancer treatment, it uses the high LET particles from the reaction 10B (n, α) 7Li to destroy cancer cells.The development of this technique began in the mid-'50s and even today it is the object of study and research in various centers around the world, Brazil has built a facility that aims to conduct research in BNCT, this facility is located next to irradiation channel number three at the research nuclear reactor IEA-R1 and has a biological shielding designed to meet the radiation protection standards. This biological shielding was developed to allow them to conduct experiments with the reactor at maximum power, so it is not necessary to turn on and off the reactor to irradiate samples. However, when the channel is opened for experiments the background radiation in the experiments salon increases and this background variation makes it impossible to perform measurements in a neutron diffraction research that utilizes the irradiation channel number six. This study aims to further improve the shielding in order to minimize the variation of background making it possible to perform the research facility in BNCT without interfering with the action of the research group of the irradiation channel number six. To reach this purpose, the code MCNP5, dosimeters and activation detectors were used to plan improvements in the biological shielding. It was calculated with the help of the code an improvement that can reduce the average heat flow in 71.2% ± 13 and verified experimentally a mean reduce of 70 ± 9% in dose due to thermal neutrons. (author)

  19. Radioisotopes Produced by Neutron Irradiation of Food

    OpenAIRE

    Seviour, Rebecca; Albright, Simon

    2016-01-01

    The use of neutrons for cargo interrogation has the potential to drastically improve threat detection. Previous research has focussed on the production of 24Na, based on the isotopes produced in pharmaceuticals and medical devices. For both the total acitivity and the ingestion dose we show that a variety of isotopes contribute and that 24Na is only dominant under certain conditions. The composition of the foods has a strong influence on the resulting activity and ingestion dose suggesting th...

  20. Synergistic effects of neutron and gamma ray irradiation of a commercial CHMOS microcontroller

    International Nuclear Information System (INIS)

    This paper presents the experimental results of a combined irradiation environment of neutron and gamma rays on 80C196KC20, which is a 16-bit high performance member of the MCS96 microcontroller family. The electrical and functional tests were made in three irradiation environments: neutron, gamma rays, combined irradiation of neutron and gamma rays. The experimental results show that the neutron irradiation can affect the total ionizing dose behaviour. Compared with the single radiation environment, the microcontroller exhibits considerably more severe degradation in neutron and gamma ray synergistic irradiation. This phenomenon may cause a significant hardness assurance problem. (condensed matter: structure, thermal and mechanical properties)

  1. Pollution of liquid argon after neutron irradiation

    CERN Document Server

    Andrieux, M L; Collot, J; de Saintignon, P; Ferrari, A; Hostachy, J Y; Hoummada, A; Martin, P; Merkel, B; Puzo, P; Sauvage, D; Wielers, M

    2001-01-01

    The purpose of the neutron facility installed at SARA is to investigate the behavior of various materials to be used in the ATLAS liquid argon calorimeter, when submitted to fast neutron radiation. The samples are placed in a liquid argon cryostat a few cm away from the neutron source. Various pieces of the electromagnetic calorimeter have been tested in order to evaluate the rate of pollution of the liquid and consequently the possible signal loss in energy measurements. The average fluence was equivalent to the maximum expected in the calorimeter in about 10 years. The most striking feature of the results is that the pollution is not due to oxygen, at least for most of it. Using a particular value of the absorption length derived from these data, a simulation was carried out and the energy signal loss in the calorimeter could be predicted. Within the limits of our present knowledge, the conclusion is that damages due to this pollution will not be a problem. (17 refs).

  2. Pollution of liquid argon after neutron irradiation

    International Nuclear Information System (INIS)

    The purpose of the neutron facility installed at SARA is to investigate the behavior of various materials to be used in the ATLAS liquid argon calorimeter, when submitted to fast neutron radiation. The samples are placed in a liquid argon cryostat a few cm away from the neutron source. Various pieces of the electromagnetic calorimeter have been tested in order to evaluate the rate of pollution of the liquid and consequently the possible signal loss in energy measurements. The average fluence was equivalent to the maximum expected in the calorimeter in about 10 years. The most striking feature of the results is that the pollution is not due to oxygen, at least for most of it. Using a particular value of the absorption length derived from these data, a simulation was carried out and the energy signal loss in the calorimeter could be predicted. Within the limits of our present knowledge, the conclusion is that damages due to this pollution will not be a problem

  3. Preliminary Neutronics Design for Fast Neutron Irradiation Facility in the KIJANG Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hongchul; Seo, Chul Gyo; Chae, Hee Taek; Kim, Myongseop [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    Current design of FNI facility in the KJRR was introduced in this paper. The performance evaluations for the FNI facility were carried out and the results meet the requirements. There is not a constraint how far gamma flux should be lowered, and the further study on this subject should be researched. The HANARO research reactor has been successfully operated in Korea. Following the experience with HANARO, KIJANG research reactor (KJRR) is now being designed by Korea Atomic Energy Research Institute (KAERI), dedicated to increasing the national radio-isotopes supply capacity including the self sufficiency of Mo-99. And the KJRR is also expected to have the capability to provide the neutron irradiation service for power semiconductor production in a large scale. This service includes not only neutron transmutation doping (NTD) facility for ingot irradiation, but also fast neutron irradiation (FNI) facility for wafer irradiation. Fast neutron irradiation for wafer is a promising technology for efficiency gain and life extension of the power semiconductor. In this work, a FNI facility has been preliminarily designed to satisfy its requirements, and the necessary calculations are carried out through Monte Carlo simulations using MCNP5 code.

  4. Thermal diffusivity of neutron-irradiated ceramics

    International Nuclear Information System (INIS)

    Fourteen candidate ceramics (eleven oxides and three nitrides) were irradiated in EBR-II to dose between 0.3 and 2.3 x 10 22 n/cm2 (E/sub n/ > 0.1 MeV) at 925, 1015, and 1100 K. Thermal diffusivity (which is approximately proportional to thermal conductivity) was subsequently measured at room temperature by a xenon flash technique. Diffusivity usually decreased sharply as a function of fluence at low doses, but tended toward saturation at higher doses. In most cases lower irradiation temperatures resulted in greater degradations in thermal diffusivity. The magnitude of reduction varied greatly with the ceramic tested, ranging from single-crystal MgAl2O4 (approx. 3%) to polycrystalline silicon oxynitride (93%). In most materials tested the reductions were great enough to raise thermal stresses significantly in low temperature, high thermal flux applications

  5. Irradiation fuel for high converter reactor and neutron irradiation method for high converter reactor

    International Nuclear Information System (INIS)

    The present invention provides fuels capable of simulating irradiation of fuels for a high conversion reactor and an irradiation method of fuels for the high conversion reactor. Namely, fuel pins to be irradiated are disposed to the central portion of a fuel assembly. The fuels of the fuel assembly surrounding the central portion comprise driver fuels which generate neutral energy spectra higher than neutron energy spectra generated by other fuel assemblies. With such a constitution, fuels capable of simulating the state of a reactor core of a high conversion reactor can be provided by a portion of a reactor core in a thermal neutron reactor. In addition, the driver fuels comprise plutonium mixed oxide fuels. With such a constitution, the plutonium enrichment degree can be increased at the periphery of the driver fuels. Neutrons of the high neutron energy spectra generated by the driver fuels at high plutonium enrichment degree are irradiated to the fuels to be irradiated. As a result, fuels capable of simulating the state of a reactor core of a high converter reactor can be provided. (I.S.)

  6. Neutron beam measurement dosimetry

    International Nuclear Information System (INIS)

    This report describes animal dosimetry studies and phantom measurements. During 1994, 12 dogs were irradiated at BMRR as part of a 4 fraction dose tolerance study. The animals were first infused with BSH and irradiated daily for 4 consecutive days. BNL irradiated 2 beagles as part of their dose tolerance study using BPA fructose. In addition, a dog at WSU was irradiated at BMRR after an infusion of BPA fructose. During 1994, the INEL BNCT dosimetry team measured neutron flux and gamma dose profiles in two phantoms exposed to the epithermal neutron beam at the BMRR. These measurements were performed as a preparatory step to the commencement of human clinical trials in progress at the BMRR

  7. Neutron beam measurement dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Amaro, C.R. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1995-11-01

    This report describes animal dosimetry studies and phantom measurements. During 1994, 12 dogs were irradiated at BMRR as part of a 4 fraction dose tolerance study. The animals were first infused with BSH and irradiated daily for 4 consecutive days. BNL irradiated 2 beagles as part of their dose tolerance study using BPA fructose. In addition, a dog at WSU was irradiated at BMRR after an infusion of BPA fructose. During 1994, the INEL BNCT dosimetry team measured neutron flux and gamma dose profiles in two phantoms exposed to the epithermal neutron beam at the BMRR. These measurements were performed as a preparatory step to the commencement of human clinical trials in progress at the BMRR.

  8. Cation disorder in high-dose, neutron-irradiated spinel

    Energy Technology Data Exchange (ETDEWEB)

    Sickafus, K.E.; Larson, A.C.; Yu, N. [Los Alamos National Lab., CA (United States)] [and others

    1995-04-01

    The objective of this effort is to determine whether MgAl{sub 2}O{sub 4} spinel is a suitable ceramic for fusion applications. The crystal structures of MgAl{sub 2}O{sub 4} spinel single crystals irradiated to high neutron fluences [>5{times}10{sup 26} n/m{sup 2} (E{sub n}>0.1 MeV)] were examined by neutron diffraction. Crystal structure refinement of the highese dose sample indicated that the average scattering strength of the tetrahedral crystal sites decreased by {approx}20% while increasing by {approx}8% on octahedral sites.

  9. Calculational evaluations of the proposal for a reference dosimetric phantom for BNCT

    International Nuclear Information System (INIS)

    Standard dosimetric phantoms are used in radiotherapy to compare irradiations under standard conditions. They provide volumes of tissue substitute for the measurement of absorbed dose and are large enough to ensure that full contribution to the absorbed dose from scattered radiation is received at the point of measurement. Aim of this study was to find out a recommendation for the boundary values of size of a reference phantom. These reference conditions for the reference measurement methods are created for 'A code of practise for dosimetry, of BNCT in Europe' project. The major objective of the project is to prepare detailed guidelines for the dosimetry of epithermal neutron beams to be used for treatment of cancer patients by Boron Neutron Capture Therapy (BNCT) at European research reactors and accelerators. For this objective Monte Carlo simulations have been carried out with MCNP 4B code in three different cubic phantoms for studying effect of different phantom sizes in important radiation components. These three phantoms are the proposed reference (measurement) phantom (20*20*20 cm), a phantom that was assumed to model an infinite phantom, and a smaller (15*15*15 cm) cubic phantom which exists in Petten BNCT facility in Netherlands. Function of the smallest phantom was to study acceptable lower limit to the phantom size to still reach the reference conditions. All the simulated phantoms were cubic water phantoms with one 0.5 cm thick (beam side) wall and three 1 cm thick walls of PMMA (polymethyl-methacrylate). The comparisons were done with calculations of the thermal, epithermal and fast neutron fluence rates in analogous points. The source specification of the MCNP runs were accordance of 250 kW FiR 1 research reactor neutron beam with 14 cm beam aperture. In order to minimise the statistical error of the Monte Carlo calculations, over 60*106 source particles were simulated for infinite and reference phantom cases. Calculation results were in good

  10. The Behaviour of Various Graphites under Neutron Irradiation

    International Nuclear Information System (INIS)

    The change of graphite properties under neutron irradiation, which is quite important for reactor designers, has been investigated closely for several years, and results have been reported in detail by several authors. The goal of these irradiation experiments was the quantitative determination of property changes as a function of irradiation dose and temperature. The concern of our own irradiation programme, which is sponsored by the Ministry of Atomic Affairs of the Federal Republic of Germany, was to study the behaviour of a wide range of reactor-grade graphites under controlled irradiation conditions. In the first part of the paper, radiation damage as a function of different types of artificial graphite is dealt with. The graphite types differed only by their degree of crystalline order, even though they were produced under the same graphitizing conditions. The differences are caused by the different graphitizabilities of the raw materials. The dependence oí the radiation damage on the graphite type seems to be of fundamental importance for the development of reactor-grade graphites with respect to various applications. Within one group the physical properties are changed in different ways for different graphite types. The differences of the unirradiated samples remain largely unchanged or are even more pronounced after irradiation. Mechanical properties, such as strength, Young's Modulus and thermal expansion, fall into this group. The well-known Wigner growth of various graphites under irradiation was studied systematically. Furthermore, such properties are reported which are levelled out to a final value under the same irradiation conditions even when the raw materials are different. This is true for the thermal and electrical conductivity, the magnetic susceptibility and to some extent for the lattice dimensions of the graphites. Finally, the effect of irradiation on the pore distribution of the various graphites is discussed. The second section ol the

  11. Precipitate stability in neutron-irradiated Zircaloy-4

    Science.gov (United States)

    Yang, W. J. S.

    1988-09-01

    Zircaloy-4, a zirconium-base alloy used extensively as cladding and core structural materials in water-cooled nuclear reactors, was examined by transmission electron microscopy, after neutron irradiation and postirradiation annealing. Phase instabilities found during irradiation at 561 K include the amorphous transformation and the dissolution of the intermetallic Zr(Fe,Cr) 2. The α-matrix is driven toward a single phase solid solution as the neutron fluence increases. This is evidenced by the continuous dissolution of the precipitate without precipitation of any new phase during irradiation. During postirradiation annealing at 833 K, solute Fe precipitates out particularly at the grain boundaries as Zr-Fe zeta-phase. Recrystallization of the amorphous precipitates occurs at a postirradiation annealing temperature of 1023 K. In general, the observed phenomena of amorphous transformation, precipitate dissolution, reprecipitation and recrystallization reflect the complex solute-point defect interactions in the α-matrix. The continuous solute dissolution during irradiation is expected to have a potential effect on irradiation growth, creep and corrosion properties of the alloy.

  12. BNCT-RTPE: BNCT radiation treatment planning environment

    Energy Technology Data Exchange (ETDEWEB)

    Wessol, D.E.; Wheeler, F.J. [Idaho National Engineering Lab., Idaho Fall, ID (United States); Babcock, R.S. [and others

    1995-11-01

    Several improvements have been developed for the BNCT radiation treatment planning environment (BNCT-Rtpe) during 1994. These improvements have been incorporated into Version 1.0 of BNCT-Rtpe which is currently installed at the INEL, BNL, Japanese Research Center (JRC), and Finland`s Technical Research Center. Platforms supported by this software include Hewlett-Packard (HP), SUN, International Business Machines (IBM), and Silicon Graphics Incorporated (SGI). A draft version of the BNCT-Rtpe user manual is available. Version 1.1 of BNCT-Rtpe is scheduled for release in March 1995. It is anticipated that Version 2.x of BNCT-Rtpe, which includes the nonproprietary NURBS library and data structures, will be released in September 1995.

  13. Neutron irradiation of candidate ceramic breeder materials of fusion reactors

    International Nuclear Information System (INIS)

    In the context of the European programs for the future fusion reactors, the Process Chemistry Department of ENEA, Casaccia Center (Rome), has been involved in preparing ceramic blanket materials as tritium breeders; a special consideration has been addressed to the nuclear characterization of LiAlO2 and Li2ZrO3. In this paper are reported neutron irradiation of ceramic specimens in TRIGA reactor and γ-spectrometric measurements for INAA purposes; and isothermal annealing of the irradiated samples and tritium extraction, by using an 'out of pile' system. (author) 3 refs.; 4 figs.; 4 tabs

  14. Effect of neutron irradiation on properties of glassy carbon

    International Nuclear Information System (INIS)

    The gas-impermeable chemically inert glassy carbon is considered as the material for manufacturing convective tubes. Its resistance to the neutron irradiation is determined. It is shown, that low crystal structure ordering in combination with the low thermal expansion coefficient conditioned its radiation shrinkage within the range of 140-750 deg C. The glassy hydrogen samples irradiation leads to: increase in the materials density; decrease in the specific electric resistance (increase in the thermal conductivity); insignificant increase in the dynamic modulus elasticity. The radiation effects decrease with the material treatment temperature increase

  15. Field-induced phase transitions in neutron-irradiated haematite

    International Nuclear Information System (INIS)

    Moessbauer spectra of three neutron-irradiated polycrystalline haematite (α-Fe2O3) samples have been recorded at 4.2 K in applied fields of up to 10 T. Field-induced phase transitions were observed, and were found to differ markedly from those that occur in non-irradiated haematite. In two lightly irradiated samples, transitions were detected from a state with Fe3+ spins near the [111] axis ('antiferromagnetic phase') to one where the spins are almost perpendicular to both the applied field and to the [111] axis ('weak ferromagnetic phase'). In the case of a heavily irradiated sample, in which the spins were initially in the weak ferromagnetic phase, the spins were observed to lie almost perpendicular to applied fields of greater than ∼ 4.5 T. The difference in behaviour in irradiated and non-irradiated haematite is attributed to a smaller difference in anisotropy energy, in the irradiated samples, between the antiferromagnetic and weak ferromagnetic phases at 4.2 K. (Author)

  16. Swelling and microstructure of neutron irradiated Inconel 706

    International Nuclear Information System (INIS)

    The swelling behaviour and the related microstructure evolution of SA INCONEL 706 irradiated up to 100dpa in Phenix as stressed tube samples and fuel pins are described. The TEM observations of the irradiated samples and corresponding unirradiated specimens annealed at the same irradiation temperature show that neutron irradiation induces the intragranular nucleation of a high density of Ni3 Ti-η platelets and small cavities which do not grow up to 100dpa. At higher temperature, it is shown that the swelling is responsible of the major part of the deformation. TEM examinations of thin foils prepared from pins areas irradiated at 5900C confirm that substantial void swelling can occur in the regions where the high density of finely distributed η platelets give place to a cellular η phase which tends to spread over the grains. At least we discuss about the correlation between the microstructure evolution under irradiation and the swelling resistance and the mechanical properties observed on this irradiated material

  17. Accelerated oxygen precipitation in fast neutron irradiated Czochralski silicon

    Institute of Scientific and Technical Information of China (English)

    Ma Qiao-Yun; Li Yang-Xian; Chen Gui-Feng; Yang Shuai; Liu Li-Li; Niu Ping-Juan; Chen Dong-Feng; Li Hong-Tao

    2005-01-01

    Annealing effect of the oxygen precipitation and the induced defects have been investigated on the fast neutron irradiated Czochralski silicon (CZ-Si) by infrared absorption spectrum and the optical microscopy. It is found that the fast neutron irradiation greatly accelerates the oxygen precipitation that leads to a sharp decrease of the interstitial oxygen with the annealing time. At room temperature (RT), the 1107cm-1 infrared absorption band of interstitial oxygen becomes weak and broadens to low energy side. At low temperature, the infrared absorption peaks appear at 1078cm-1, 1096cm-1, and 1182cm-1, related to different shapes of the oxygen precipitates. The bulk microdefects,including stacking faults, dislocations and dislocation loops, were observed by the optical microscopy. New or large stacking faults grow up when the silicon self-interstitial atoms are created and aggregate with oxygen precipitation.

  18. Elastic stability of high dose neutron irradiated spinel

    Energy Technology Data Exchange (ETDEWEB)

    Li, Z.; Chan, S.K. [Argonne National Lab., Chicago, IL (United States); Garner, F.A. [Pacific Northwest Lab., Richland, WA (United States)] [and others

    1995-04-01

    The objective of this effort is to identify ceramic materials that are suitable for fusion reactor applications. Elastic constants (C{sub 11}, C{sub 12}, and C{sub 44}) of spinel (MgAl{sub 2}O{sub 4}) single crystals irradiated to very high neutron fluences have geen measured by an ultrasonic technique. Although results of a neutron diffraction study show that cation occupation sites are significantly changed in the irradiated samples, no measurable differences occurred in their elastic properties. In order to understand such behavior, the elastic properties of a variety of materials with either normal or inverse spinel structures were studied. The cation valence and cation distribution appear to have little influence on the elastic properties of spinel materials.

  19. Neutron irradiation and compatibility testing of Li2O

    International Nuclear Information System (INIS)

    A study was made of the neutron-irradiation behavior of 6Li-enriched Li2O material in EBR-II. In addition, a stress-corrosion study was performed ex-reactor to test compatibility of Li2O materials with a variety of stainless steels. Results of the irradiation testing showed that tritium and helium retention in the Li2O (approx. 89% dense) lessened with neutron exposure. Helium and tritium retention appear to approach steady-state after approx. 1% 6Li burnup. The stress-corrosion studies, using 316 stainless steel (Ti-modified) and a 35% Ni alloy, showed that stress does not enhance the corrosion, and that dry Li2O is not significantly corrosive, the LiOH content producing the corrosive effects. Corrosion, in general, was not severe as a passivation in sealed capsules seemed to occur after a time, greatly reducing corrosion rates

  20. Behaviour of carbon-14 in graphite irradiated by neutrons

    International Nuclear Information System (INIS)

    The method of carbon-14 extraction from graphite irradiated by neutrons based on the thermal effect to graphite in a technological vacuum or air current is a basically new approach. When irradiated graphite is heated in a technological vacuum and in an air current, extraction of carbon-14 takes place and reaches as much as 99.5%. The mass of graphite decreases approximately by 10% in every 5 hours of heating. At the same time, its substance in different units can vary in wide ranges: from 3,5 to 110 kBq/g. This can be explained in terms of both the different substance of nitrogen impurities in graphite and different fluency of thermal neutrons

  1. In vitro antileishmanial properties of neutron-irradiated meglumine antimoniate

    International Nuclear Information System (INIS)

    Pentavalent antimony, as meglumine antimoniate (Glucantime) or sodium stibogluconate (Pentostam), is the main treatment for leishmaniasis, a complex of diseases caused by the protozoan Leishmania, and an endemic and neglected threat in Brazil. Despite over half a century of clinical use, their mechanism of action, toxicity and pharmacokinetic data remain unknown. The analytical methods for determination of antimony in biological systems remain complex and have low sensitivity. Radiotracer studies have a potential in pharmaceutical development. The aim of this study was to obtain a radiotracer for antimony, with suitable physical and biological properties. Meglumine antimoniate was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes 122 Sb and 124 Sb, with high radionuclidic purity and good specific activity. This compound showed the same antileishmanial activity as the native compound. The use of the radiotracers, easily created by neutron irradiation, could be an interesting tool to solve important questions in antimonial pharmacology. (author)

  2. In vitro antileishmanial properties of neutron-irradiated meglumine antimoniate

    Energy Technology Data Exchange (ETDEWEB)

    Borborema, Samanta Etel Treiger; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), SP (Brazil). Lab. de Biologia Molecular]. E-mail: samanta@usp.br; Osso Junior, Joao Alberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), SP (Brazil). Centro de Radiofarmacia]. E-mail: jaosso@ipen.br; Andrade Junior, Heitor Franco de [Instituto de Medicina Tropical de Sao Paulo (IMT-SP), SP (Brazil). Lab. de Protozoologia]. E-mail:hfandrad@usp.br

    2005-10-15

    Pentavalent antimony, as meglumine antimoniate (Glucantime) or sodium stibogluconate (Pentostam), is the main treatment for leishmaniasis, a complex of diseases caused by the protozoan Leishmania, and an endemic and neglected threat in Brazil. Despite over half a century of clinical use, their mechanism of action, toxicity and pharmacokinetic data remain unknown. The analytical methods for determination of antimony in biological systems remain complex and have low sensitivity. Radiotracer studies have a potential in pharmaceutical development. The aim of this study was to obtain a radiotracer for antimony, with suitable physical and biological properties. Meglumine antimoniate was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes {sup 122} Sb and {sup 124} Sb, with high radionuclidic purity and good specific activity. This compound showed the same antileishmanial activity as the native compound. The use of the radiotracers, easily created by neutron irradiation, could be an interesting tool to solve important questions in antimonial pharmacology. (author)

  3. Neutrons flux distribution in a 252Cf irradiation cell for neutron activation analysis

    International Nuclear Information System (INIS)

    A 100 microgram Californium-252 (252Cf) neutron source was embedded in a pure paraffin moderator surrounded by neutron and gamma ray shields to be used as an irradiation cell facility for NAA experiments. The cell is provided with a direct horizontal channel and a Vertical Tangential Irradiation Channel (VTIC) that are parallel to the source axis. The cadmium difference method was used in determining the thermal and epithermal neutron flux distributions along the axis of the (VTIC). For this purpose, 10 pairs of bare and cadmium covered pure gold foils were irradiated at the same positions along the axis of the (VTIC) in two separate runs. The absolute efficiency of the HPGe detector at the gamma ray energy 411.8 keV of 198 Au, was found to be 0.0318 ± 0.0025.The obtained distributions of thermal and epithermal neutron fluxes were tabulated and graphically presented. An evidence for contributions from 252Cf fission by epithermal neutrons was noticed. As an application on this facility the concentration of gold in an ore sample from gold - bearing ivory vein of wady Allaqui (at south west of eastern desert) was determined. It was found to be 612 ± 6 ppm

  4. Irradiation embrittlement of the shippingport neutron shield tank

    International Nuclear Information System (INIS)

    The irradiation embrittlement of the Shippingport neutron shield tank material has been characterized. The results indicate embrittlement of the A212 grade B steel from low-temperature, low-flux environment. However, the shifts in Charpy transition temperature are lower than those for the HFIR surveillance samples. The data agree well with results from high flux test reactors. Annealing studies indicate complete recovery of embrittlement after a 2-h anneal at 400 degree C. 10 refs., 12 figs., 1 tab

  5. Impact of neutron irradiation on ITER candidate Hall sensors

    Czech Academy of Sciences Publication Activity Database

    Sentkerestiová, Jana; Ďuran, Ivan; Viererbl, L.; Bolshakova, I.

    Vol. 31F. Varšava: European Physical Society, 2007 - (Gasior, P.; Wolowski, J.), s. 2.152-2.152. (Europhysics Conference Abstracts. ECA Vol. 31F (2007)). ISBN 978-83-926290-0-9. [EPS Conference on Plasma Physics/34rd./. Varšava (PL), 02.07.2007-06.07.2007] Institutional research plan: CEZ:AV0Z20430508 Keywords : Hall sensors * neutron irradiation Subject RIV: BL - Plasma and Gas Discharge Physics

  6. Impact of neutron irradiation on ITER candidate Hall sensors

    Czech Academy of Sciences Publication Activity Database

    Sentkerestiová, Jana; Ďuran, Ivan; Bolshakova, I.; Viererbl, L.

    Varšava: European Physical Society, 2007. s. 2-2. [EPS Conference on Plasma Physics/34rd./. 02.07.2007-06.07.2007, Varšava] R&D Projects: GA MPO 2A-1TP1/101 Institutional research plan: CEZ:AV0Z20430508 Keywords : Hall sensors * neutron irradiation * ITER Subject RIV: BL - Plasma and Gas Discharge Physics

  7. Neutron irradiation effects on high Nicalon silicon carbide fibers

    Energy Technology Data Exchange (ETDEWEB)

    Osborne, M.C.; Steiner, D.; Snead, L.L. [Oak Ridge National Laboratory, TN (United States)

    1996-10-01

    The effects of neutron irradiation on the mechanical properties and microstructure of SiC and SiC-based fibers is a current focal point for the development of radiation damage resistant SiC/SiC composites. This report discusses the radiation effects on the Nippon Carbon Hi-Nicalon{trademark} fiber system and also discusses an erratum on earlier results published by the authors on this material. The radiation matrix currently under study is also summarized.

  8. Separation of Protactinium from Neutron Irradiated Thorium Oxide

    International Nuclear Information System (INIS)

    The chemical separation of thorium and protactinium can be carried out by leaching most of the last one, about 95%, with aqueous HF from neutron irradiated thorium oxide. This leaching reaction la highly favored by the transformation reaction of the ThO2 material into ThF4. For both reactions, leaching and transformation, the reagents concentration, agitation speed and temperature influences were studied and the activation energies were found. (Author) 18 refs

  9. Comparative effects of neutron irradiation and X irradiation on the embryonic development of the rat

    International Nuclear Information System (INIS)

    Our aim was to compare the dose-response relationship for the embryotoxic effects of 0.43 MeV neutrons with those of 240 kVp X rays after in utero exposures during early organogenesis in the rat. At 9.5 days after conception, pregnant rats were exposed to 0.025 to 0.35 Gy 0.43 MeV neutrons at a dose rate of 0.04 to 0.07 Gy/h. Comparable biological effects were produced using 0.50 to 2.05 Gy 240 kVp X rays. Neutron irradiation produced a greater proportion of offspring with very low body weight than with malformations when compared to X rays. There were no embryotoxic effects observed at neutron exposures of 0.025, 0.049, 0.079, 0.10, 0.15, and 0.20 Gy or X-ray exposures of 0.50 and 0.96 Gy. Taken together, the results suggest that the mechanisms by which neutron irradiation affects embryonic development may, in part, be both quantitatively and qualitatively different from those by which X irradiation affects development. These results support the generalization that the embryo exhibits a nonlinear response to increasing doses of ionizing radiations during the period of early organogenesis. 25 refs., 3 tabs

  10. Effects of the neutronic irradiation on the impact tests

    International Nuclear Information System (INIS)

    The changes that the Charpy curves suffer when steel is exposed to neutronic fluence are studied. Three steels with different chemical composition were chosen, two of them (JPF and JPJ) being treated at only one neutronic fluence, while the last one (JRQ) was irradiated at three fluences. In this way, it was possible to compare the effect of increasing the neutronic dose, and to study the experimental results as a function of the steel chemical composition. Two characteristic facts have been observed: the displacement of the curve at higher temperatures, and decrease of the upper shelf energy (USE). The mechanical recovery of the materials after two different thermal treatments is also described, and a comparation between the experimental results obtained and the damage prediction formulas given by different regulatory international organisms in the nuclear field is established. Author. 11 refs

  11. Cation disorder in high-dose, neutron-irradiated spinel

    International Nuclear Information System (INIS)

    The objective of this effort is to determine whether MgAl2O4 spinel is a suitable ceramic for fusion applications. Here, the crystal structures of MgAl2O4 spinel single crystals irradiated to high neutron fluences [>5·1026 n/m2 (En > 0.1 MeV)] were examined by neutron diffraction. Crystal structure refinement of the highest dose sample indicated that the average scattering strength of the tetrahedral crystal sites decreased by ∼ 20% while increasing by ∼ 8% on octahedral sites. Since the neutron scattering length for Mg is considerably larger than for Al, this results is consistent with site exchange between Mg2+ ions on tetrahedral sites and Al3+ ions on octahedral sites. Least-squares refinements also indicated that, in all irradiated samples, at least 35% of Mg2+ and Al3+ ions in the crystal experienced disordering replacements. This retained dpa on the cation sublattices is the largest retained damage ever measured in an irradiated spinel material

  12. Influence of neutron irradiation on the tritium retention in beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Rolli, R.; Ruebel, S.; Werle, H. [Forschungszentrum Karlsruhe, Inst. fuer Neutronenphysik und Reaktortechnik, Karlsruhe (Germany); Wu, C.H.

    1998-01-01

    Carbon-based materials and beryllium are the candidates for protective layers on the components of fusion reactors facing plasma. In contact with D-T plasma, these materials absorb tritium, and it is anticipated that tritium retention increases with the neutron damage due to neutron-induced traps. Because of the poor data base for beryllium, the work was concentrated on it. Tritium was loaded into the samples from stagnant T{sub 2}/H{sub 2} atmosphere, and afterwards, the quantity of the loaded tritium was determined by purged thermal annealing. The specification of the samples is shown. The samples were analyzed by SEM before and after irradiation. The loading and the annealing equipments are contained in two different glove boxes with N{sub 2} inert atmosphere. The methods of loading and annealing are explained. The separation of neutron-produced and loaded tritium and the determination of loaded tritium in irradiated samples are reported. Also the determination of loaded tritium in unirradiated samples is reported. It is evident that irradiated samples contained much more loaded tritium than unirradiated samples. The main results of this investigation are summarized in the table. (K.I.)

  13. Boron neutron capture therapy for advanced and/or recurrent cancers in the oral cavity

    International Nuclear Information System (INIS)

    This preliminary study of 5 patients with advanced and/or recurrent cancer in the oral cavity was performed to evaluate the effectiveness of Boron Neutron Capture Therapy (BNCT). The patients received therapy with the 10B-carrier p-boronophenylalanine (BPA) with or without borocaptate sodium (BSH) and irradiation thereafter with epithermal neutrons. All underwent 18F-BPA PET studies before receiving BNCT to determine the accumulation ratios of BPA in tumor and normal tissues. The tumor mass was decreased in size and at minimum a transient partial response was achieved in all cases, though rapid tumor re-growth was observed in 2. Although tentative clinical responses and improvements in quality of life were recognized, obliteration of the tumor was not obtained in any of the cases. Additional studies are required to determine the utility and indication of BNCT for oral cancer. (author)

  14. Joining techniques development for neutron irradiation tests and post irradiation examinations in JMTR-HL

    International Nuclear Information System (INIS)

    The hot laboratory (JMTR-HL) associated with the JMTR (Japan Materials Testing Reactor) was founded to examine the material and fuel specimens irradiated mainly in the JMTR. Through the post-irradiation examinations (PIEs) have been developed and performed, the JMTR-HL contributes not only to research of materials for light water reactors, fast reactors, high temperature gas reactor, and fusion reactor, but also to production of domestic industrial radio isotopes like 192Ir. As the part of PIE technology development, several kinds of welding techniques have been systematically developed. These research and development of welding techniques such as circumference and sealing for irradiation capsules and rewelding with irradiated materials were implemented under the remote-controlled conditions in the hot cells. These techniques are very indispensable for the neutron irradiation tests and PIEs to be conducted in the JMTR. (author)

  15. Neutron irradiation behavior of ITER candidate beryllium grades

    Energy Technology Data Exchange (ETDEWEB)

    Kupriyanov, I.B.; Gorokhov, V.A.; Nikolaev, G.N. [A.A.Bochvar All-Russia Scientific Research Inst. of Inorganic Materials (VNIINM), Moscow (Russian Federation); Melder, R.R.; Ostrovsky, Z.E.

    1998-01-01

    Beryllium is one of the main candidate materials both for the neutron multiplier in a solid breeding blanket and for the plasma facing components. That is why its behaviour under the typical for fusion reactor loading, in particular, under the neutron irradiation is of a great importance. This paper presents mechanical properties, swelling and microstructure of six beryllium grades (DshG-200, TR-30, TshG-56, TRR, TE-30, TIP-30) fabricated by VNIINM, Russia and also one - (S-65) fabricated by Brush Wellman, USA. The average grain size of the beryllium grades varied from 8 to 25 {mu}m, beryllium oxide content was 0.8-3.2 wt. %, initial tensile strength was 250-680 MPa. All the samples were irradiated in active zone of SM-3 reactor up to the fast neutron fluence (5.5-6.2) {center_dot} 10{sup 21} cm{sup -2} (2.7-3.0 dpa, helium content up to 1150 appm), E > 0.1 MeV at two temperature ranges: T{sub 1} = 130-180degC and T{sub 2} = 650-700degC. After irradiation at 130-180degC no changes in samples dimensions were revealed. After irradiation at 650-700degC swelling of the materials was found to be in the range 0.1-2.1 %. Beryllium grades TR-30 and TRR, having the smallest grain size and highest beryllium oxide content, demonstrated minimal swelling, which was no more than 0.1 % at 650-700degC and fluence 5.5 {center_dot} 10{sup 21} cm{sup -2}. Tensile and compression test results and microstructure parameters measured before and after irradiation are also presented. (author)

  16. Early clinical experience of boron neutron capture therapy for glioblastoma multiforme

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a binary treatment modality that can selectively irradiate tumor tissue. BNCT uses drugs containing a stable isotope of boron. 10B, to sensitize tumor cells to irradiation by low energy (thermal) neutrons. The interaction of the 10B with a thermal neutron (neutron capture) causes the 10B nucleus to split, releasing an alpha particle and a lithium nucleus. These products of the 10B(n, α)7Li reaction are very damaging to cells but have a combined path length in tissue of approximately 14 μm, or roughly the diameter of one or two cells. Thus, most of the ionizing energy imparted to tissue is localized to 10B-loaded cells

  17. Early clinical experience of boron neutron capture therapy for glioblastoma multiforme

    Energy Technology Data Exchange (ETDEWEB)

    Joel, D.D.; Bergland, R.; Capala, J. [and others

    1995-12-31

    Boron neutron capture therapy (BNCT) is a binary treatment modality that can selectively irradiate tumor tissue. BNCT uses drugs containing a stable isotope of boron. {sup 10}B, to sensitize tumor cells to irradiation by low energy (thermal) neutrons. The interaction of the {sup 10}B with a thermal neutron (neutron capture) causes the {sup 10}B nucleus to split, releasing an alpha particle and a lithium nucleus. These products of the {sup 10}B(n, {alpha}){sup 7}Li reaction are very damaging to cells but have a combined path length in tissue of approximately 14 {mu}m, or roughly the diameter of one or two cells. Thus, most of the ionizing energy imparted to tissue is localized to {sup 10}B-loaded cells.

  18. Cavity nucleation and growth during helium implantation and neutron irradiation of Fe and steel

    DEFF Research Database (Denmark)

    Eldrup, Morten Mostgaard; Singh, Bachu Narain

    In order to investigate the role of He in cavity nucleation in neutron irradiated iron and steel, pure iron and Eurofer-97 steel have been He implanted and neutron irradiated in a systematic way at different temperatures, to different He and neutron doses and with different He implantation rates....

  19. Utilization of the IEA-R1 reactor for DNA irradiation

    International Nuclear Information System (INIS)

    Full text: The Beam Hole no.3(BHno.3) of the IEA-R1 Reactor of IPEN-CNEN, Sao Paulo was designed for research in Boron Neutron Capture Therapy (BNCT). This facility will be used for study of radiation-induced DNA damage. The increasing knowledge of the cellular response to radiation damage has contributed to further improvements in radiation therapy. In order to reduce the gamma contamination and have sufficient neutron fluxes for irradiation of DNA molecule, it will be necessary to collocate several neutron filters in the beam hole. The choice of the adequate filter arrangement was carried with Monte Carlo-4B code. Our propose is to irradiate DNA molecule with thermal, epithermal and fast neutron from BNCT Research facility at the IEA-R1m reactor. The obtained results of simulation will be shown in this paper. (author)

  20. Simulation of the BNCT of Brain Tumors Using MCNP Code: Beam Designing and Dose Evaluation

    International Nuclear Information System (INIS)

    BNCT is an effective method to destroy brain tumoral cells while sparing the healthy tissues. The recommended flux for epithermal neutrons is 109 n/cm2s, which has the most effectiveness on deep-seated tumors. In this paper, it is indicated that using D-T neutron source and optimizing of Beam Shaping Assembly leads to treating brain tumors in a reasonable time where all International Atomic Energy Agency recommended criteria are met. The proposed Beam Shaping Assembly based on a D-T neutron generator consists of a neutron multiplier system, moderators, reflector, and collimator. The simulated Snyder head phantom is used to evaluate dose profiles in tissues due to the irradiation of designed beam. Monte Carlo Code, MCNP-4C, was used in order to perform these calculations. The neutron beam associated with the designed and optimized Beam Shaping Assembly has an adequate epithermal flux at the beam port and neutron and gamma contaminations are removed as much as possible. Moreover, it was showed that increasing J/Φ, as a measure of beam directionality, leads to improvement of beam performance and survival of healthy tissues surrounding the tumor. According to the simulation results, the proposed system based on D-T neutron source, which is suitable for in-hospital installations, satisfies all in-air parameters. Moreover, depth-dose curves investigate proper performance of designed beam in tissues. The results are comparable with the performances of other facilities.

  1. Boron Neutron Capture Therapy at IRT -Sofia Research Reactor. Basics and activities

    International Nuclear Information System (INIS)

    The Boron Neutron Capture Therapy (BNCT) proved itself to be vital option for severe cancer treatment during the last 20 years. The building of BNCT facility was a main task of the reconstruction of the IRT-Sofia research reactor at the Institute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences. A number of activities in the development of appropriate infrastructure including accumulation of the existing experience, and creation of a multidisciplinary team and infrastructure, collecting BNCT oriented information in the IT-system was done. The technical design of the BNCT irradiation channel followed the beam tube configuration of the reactor at the Massachusetts Institute of Technology, USA, and took also into account the limits of the reactor construction geometry. The results of neutron and gamma transport calculations performed for the reactor model showed that the facility would be able to supply epithermal neutron flux with quality, equal to the best values reached in the world until now. The BNCT will play a significant role in the sustainable utilization of the reactor for cancer treatment of patients from the Balkan region. (authors)

  2. Neutron diffraction analysis of Cr–Ni–Mo–Ti austenitic steel after cold plastic deformation and fast neutrons irradiation

    International Nuclear Information System (INIS)

    A quantitative assessment is presented of the dislocation density and relative fractions of edge and screw dislocations in reactor-steel samples 16Cr–15Ni–3Mo–1Ti subjected to preliminary cold deformation by rolling and subsequent fast neutron irradiation using neutron diffraction analysis. The Williamson–Hall modified method was used for calculations. It is shown that the fast neutron irradiation leads to a decrease in the density of dislocations that appeared after samples deformation. The applicability of neutron diffraction analysis to the examination of dislocation structure of deformed and irradiated materials is shown

  3. INEL BNCT Program: Volume 5, No. 9. Bulletin, September 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, A.L. [ed.

    1991-12-31

    This Bulletin presents a summary of accomplishments and highlights of the Idaho National Engineering Laboratory`s (INEL) Boron Neutron Capture Therapy (BNCT) Program for September 1991. This bulletin includes information on the brain tumor and melanoma research programs, Power Burst Facility (PBF) technical support and modifications, PBF operations, and updates to the animal data charts.

  4. Enterphase Integrity of Neutron Irradiated SiC Composites

    Energy Technology Data Exchange (ETDEWEB)

    Lara-Curzio, E.; Snead, L.L.

    1999-11-30

    SiC/SiC composites were fabricated from Hi-Nicalon{trademark} fibers with carbon, porous SiC and multilayer SiC interphases. These materials were then irradiated in the High Flux Beam Reactor with fast neutrons at 260 and 900-1060 degrees C to a dose of 1.1X10{sup 25} n/m{sup 2} corresponding to 1.1 displacements per atom (dpa). Results are presented for bend strength of both non-irradiated and irradiated materials. Within the interphases studied the multilayer SiC interphase material showed the least degradation (8-20%) in ultimate bend stress, while porous SiC underwent the greatest degradation ({approximately}35%). The Fiber matrix interphases are studied with TEM for both nonirradiated and irradiated materials. While no irradiation induced microstructural evolution of the interphase was observed, debonding of the interphase from the fiber was observed for all cases. This debonding is attributed to tensile stresses developed at the interface due to densification of the Hi-Nicalon{trademark} fiber. Residual stress analysis of the fiber matrix interface indicates that the irradiation-induced densification of Hi-Nicalon{trademark} and the volumetric expansion of the CVD SiC matrix cause tensile stresses well in excess of those which can be withstood by these, or any other viable SiC composite interphase.

  5. Neutron irradiation creep experiments on austenitic stainless steel alloys

    International Nuclear Information System (INIS)

    Results of measurements of the neutron induced creep elongation on AMCR-steels (Mn-base), on 316 CE-reference steels, and on US 316 jand US PCA steels are reported. It was found that the stationary creep rate is not very sensitive to variations of the irradiation temperature between 300 and 400 degC and that the stress-exponent of plastically deformed and of annealed materials is n ≅ and n ≅ 1.59, respectively. A small primary creep stage is found in annealed materials. Deformed materials show a negative creep elongation at the beginning of the irradiation, which increases for decreasing stresses and decreases for increasing irradiation temperatures. (author). 7 refs.; 7 figs.; 1 tab

  6. INEL BNCT research program: Annual report, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Venhuizen, J.R. [ed.

    1996-04-01

    This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1995. Contributions from the principal investigators about their individual projects are included, specifically, physics (treatment planning software, real-time neutron beam measurement dosimetry), and radiation biology (large animal models efficacy studies). Design of a reactor based epithermal neutron extraction facility is discussed in detail. Final results of boron magnetic resonance imagining is included for both borocaptate sodium (BSH) and boronophenylalanine (BPA) in rats, and BSH in humans. Design of an epithermal neutron facility using electron linear accelerators is presented, including a treatise on energy removal from the beam target. Information on the multiple fraction injection of BSH in rats is presented.

  7. INEL BNCT research program: Annual report, 1995

    International Nuclear Information System (INIS)

    This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1995. Contributions from the principal investigators about their individual projects are included, specifically, physics (treatment planning software, real-time neutron beam measurement dosimetry), and radiation biology (large animal models efficacy studies). Design of a reactor based epithermal neutron extraction facility is discussed in detail. Final results of boron magnetic resonance imagining is included for both borocaptate sodium (BSH) and boronophenylalanine (BPA) in rats, and BSH in humans. Design of an epithermal neutron facility using electron linear accelerators is presented, including a treatise on energy removal from the beam target. Information on the multiple fraction injection of BSH in rats is presented

  8. Study of the potential of using 9B(p,n) for BNCT clinical trials

    International Nuclear Information System (INIS)

    The potential of using a 30-MeV proton accelerator utilizing the 9Be(p,n)9B reaction as a neutron source for BNCT (Boron Neutron Capture Therapy) was investigated. MCNPX (Monte Carlo Neutron Photon-transport code X) was used to calculated neutron spectra and yields for comparison against existing experimental data and for the moderator optimization. Moderator performance was assessed using MCNPX and clinical efficacy was assessed using BNCT-RTPE to estimate in-phantom dose distributions and neutron fluences. The optimized source and moderator gave comparable tumor doses and treatment times to the clinical trials recently completed at the Brookhaven Medical Research Reactor (BMRR). (author)

  9. Effect of roentgen, cyclotron neutron, or mixed neutron-photon fractionated irradiation of mice

    International Nuclear Information System (INIS)

    Mice were whole-body-irradiated with 5 fractions of roentgen rays in 5 days, 5 fractions of cycotron neutrons in 5 days, or with mixed neutron-photon fractionated radiation, in the sequence n-n-x-x-x or n-x-x-x-n. The LD50 sub(/) 4 day values were determined. Roentgen rays and neutrons interact in the additive manner in the mixed fractionation schemes: effective dose per fraction is as predicted from the roentgen ray-only and neutron-only experiments. This essentially agrees with HENDRY et coll. (1976). However, no trend was found towards a less-than-additive effect which was observed by those authors and has also been suggested in skin response to mixed schemes (NELSON et coll 1975). (author)

  10. Neutron irradiation of superconductors and damage energy scaling of different neutron spectra

    Science.gov (United States)

    Hahn, P. A.; Weber, H. W.; Guinan, M. W.; Birtcher, R. C.; Brown, B. S.; Greenwood, L. R.

    1985-08-01

    Three different neutron sources were used to irradiate identical sets of NbTi superconductors up to about half the lifetime dose of a superconducting magnet in a fusion reactor. Based on a careful source characterization of the TRIGA Mark-II reactor in Vienna, the spallation neutron source IPNS at Argonne and the 14 MeV neutron source RTNS-II at Livermore, the damage energy cross sections were calculated for four different types of NbTi alloys (42, 46.5, 49 and 54 wt % Ti). The experimental results on the variations of critical current densities j sub c with neutron dose are found to scale within the experimental uncertainties with the appropriate damage energy cross sections. This first explicit proof of damage energy scaling for j sub c-variations in superconductors is considered to be most valuable for the evaluation of radiation damage in superconductors under fusion reactor conditions.

  11. Neutron irradiation of superconductors and damage energy scaling of different neutron spectra

    International Nuclear Information System (INIS)

    Three different neutron sources were used to irradiate identical sets of NbTi superconductors up to about half the lifetime dose of a superconducting magnet in a fusion reactor. Based on a careful source characterization of the TRIGA Mark-II reactor in Vienna, the spallation neutron source IPNS at Argonne and the 14 MeV neutron source RTNS-II at Livermore, the damage energy cross sections were calculated for four different types of NbTi alloys (42, 46.5, 49 and 54 wt % Ti). The experimental results on the variations of critical current densities j/sub c/ with neutron dose are found to scale within the experimental uncertainties with the appropriate damage energy cross sections. This first explicit proof of damage energy scaling for j/sub c/-variations in superconductors is considered to be most valuable for the evaluation of radiation damage in superconductors under fusion reactor conditions. 12 refs., 5 figs., 2 tabs

  12. Post-irradiation experiments on physical thermal and microstructural properties of neutron-irradiated ceramics. 2

    International Nuclear Information System (INIS)

    Succeeding to the report on the post-irradiation experiments conducted in the previous year, this is a summary report on the post-irradiation experiments of physical, thermal and microstructural properties of neutron-irradiated various ceramics, which are expected to be applied to the in-core materials of an Advanced Fast Breeder Reactor in near future. Four candidate ceramics, Al2O3, AlN, SiC and Si3N4 were fast-neutron-irradiated up to a fluence of 3.9x1026 n/m2, different irradiation conditions from the previous report specimens, in the CMIR-4 rig in the JOYO experimental fast reactor in JNC. The following observations were performed: (1) Microstructural observation by means of transmission electron microscopy, (2) Measurement of swelling, (3) Measurement of thermal diffusivity by a laser-flash method, (4) Recovery of swelling by isochronal annealing, and (5) Recovery of thermal diffusivity by isochronal annealing. Obtained main results are summarized as follows. Macroscopic length changes by neutron irradiation of Al2O3 and AlN were measured to be 1.8-2.0% and these of SiC and Si3N4 to be 0.2-0.4%, respectively. Thermal diffusivities of all irradiated materials degraded to 0.03-0.05 cm2/s, irrespective of materials which had large difference before irradiation. Microstructural observation of irradiated materials by TEM revealed that Al2O3 contained high-density loops, microvoids in grains, and microcracking along grain boundaries, AlN contained high-density loops and microcracking along grain boundaries, SiC contained high-density loops, and Si3N4 contained loops lying on the planes parallel to the c-axis, respectively. Macroscopic length of Al2O3 and AlN started to recover at around 800deg or 1100degC, respectively, irrespective of irradiation temperature, and reduced quickly. Macroscopic length of SiC recovered gradually from near the irradiation temperature. Si3N4 showed no recovery in macroscopic length within the present experimental conditions. Thermal

  13. Development of boron concentration analysis system and techniques for testing performance of BNCT facility

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hee Dong; Kim, Chang Shuk; Byun, Soo Hyun; Lee, Jae Yun; Sun, Gwang Min; Kim, Suk Kwon [Seoul National University, (Korea)

    2000-04-01

    I. Objectives and Necessity of the Project. Development of a boron concentration analysis system used for BNCT. Development of test techniques for BNCT facility. II. Contents and Scopes of the Project. (1) Design of a boron concentration analysis system at HANARO. (2) Component machining and instruments purchase, performance test. (3) Calculation and measurement of diffracted polychromatic beam quality. (4) Test procedures for boron concentration analysis system and BNCT facility. III. Result of the Project (1) Diffracted neutron beam quality for boron concentration analysis. (neutron flux: 1.2 * 10{sup 8} n/cm{sup 2}s, Cd-ratio : 1,600) (2) Components and instruments of the boron concentration analysis system. (3) Diffracted neutron spectrum and flux. (4) Test procedures for boron concentration analysis system and BNCT facility. 69 refs., 44 figs., 14 tabs. (Author)

  14. Indication and possibility of boron neutron capture therapy in head and neck cancer

    International Nuclear Information System (INIS)

    Background: Boron neutron capture therapy (BNCT) is a targeted type of radiotherapy that has a number of significant advantages over conventional external beam photon irradiation, especially in that radiation can be selectively delivered to tumor cells. We had, first in the world, treated with BNCT for a patient with recurrent head and neck cancer (HNC) in 2001. Methods : From December, 2001 to February, 2013, we had treated 37 patients with recurrent HNC by means of 54 applications of BNCT at Kyoto University Research Reactor Institute (KURRI) and Japan Atomic Energy Agency (JAEA). All of them had received standard therapy and subsequently developed recurrent disease for which there were no other treatment options. Results : All of the (1) Regression rates were complete response (CR) : 19 patients (51%), partial response (PR) : 14(38%), progressive disease (PD) : 3(8%), and not evaluated (NE) : 1(3%) patient. (2) The overall patient response rate was 91%, though all the patients had advanced disease. The 4-year and 7-year OS rates were 42% and 36%, respectively. (3) BNCT improved quality of life (QOL), performance status (PS) and survival times. (4) The primary adverse events were brain necrosis, osteomyelitis and transient mucositis and alopecia. Conclusions : Our results indicate that we could make sure that safety and effectiveness of BNCT, and BNCT represents a new and promising treatment modality in patients for whom there are no other treatment options. (author)

  15. Functional and histological assessment of the radiobiology of normal rat lung in BNCT

    International Nuclear Information System (INIS)

    This study investigated the radiobiology and sensitivity of the normal rat lung to Boron Neutron Capture Therapy (BNCT) radiation. Rat thorax irradiations were carried out with x-rays or with neutrons in the presence or absence of p-boronophenylalanine (BPA). Lung damage were assessed functionally with breathing rate measurement up to 180 days after irradiation and then histologically. Breathing rates 20% (∼3 σ) above the control group (sham-irradiated rats) mean were considered as positive responses to lung radiation damage. Though most responding animals demonstrated radiation induced pneumonitis (≤110 days) as well as pulmonary fibrosis (>110 days), some animals receiving neutrons plus BPA showed only the latter. The breathing rate dose response data were fit using probit analysis. The ED50 values measured for x-rays, neutron beam only, and neutrons plus BPA were 11.5±0.4 Gy, 9.2±0.5 Gy, and 6.7±0.4 Gy, respectively. The biological weighting factors for the neutron beam (n+γ), the thermal neutron dose component, and the 10B dose component were determined to be 1.2±0.1, 2.2±0.4, and 2.3±0.3, respectively. The histological dose response curves were linear. Consistent with the functional assay, the weighting factors measured histologically were 1.2±0.1 for the thermal neutron beam and 1.9±0.2 for the 10B dose component. (author)

  16. SANS response of VVER440-type weld material after neutron irradiation, post-irradiation annealing and reirradiation

    OpenAIRE

    Ulbricht, Andreas; Bergner, Frank; Boehmert, Juergen; Valo, Matti; Mathon, Marie-Helene; Heinemann, Andre

    2007-01-01

    Abstract It is well accepted that the reirradiation behaviour of reactor pressure vessel (RPV) steel after annealing can be different from the original irradiation behaviour. We present the first small-angle neutron scattering (SANS) study of neutron irradiated, annealed and reirradiated VVER440-type RPV weld material. The SANS results are analysed both in terms of the size distribution of irradiation-induced defect/solute atom clusters and in terms of the ratio of total and nuclea...

  17. DT fusion neutron irradiation of LLL 316 stainless steel and SLL silica samples

    International Nuclear Information System (INIS)

    The DT fusion neutron irradiation of six LLL 316 stainless steel samples and 24 SLL pure silica samples is described. The sample position, beam-on time, and neutron dose record are given. The maximum neutron fluence on any sample was 1.52 x 1017 neutrons/cm2

  18. Neutron irradiation effects at cryogenic temperature on the structural materials for cold neutron source

    International Nuclear Information System (INIS)

    In recent years, the demand on cold neutron is growing in the neutron scattering research. According to such requirements the cold neutron source (CNS) is planned for the upgraded JRR-3. The moderator cell in CNS, which contains liquid hydrogen, will be irradiated for long time by high fluence in the deuterium reflector region. The moderator cell has to endure quite wide range of temperature from the liquide hydrogen temperature (about 20 K) to high temperature (about 400 deg C). Therefore the moderator cell, with quite thin thickness and ovoid shape to moderate and draw out neutrons effectively, must have so high mechanical strength as to keep liquid hydrogen in the severe conditions. In this report, the mechanical tests on the materials for the moderator cell after the irradiation in the cryogenic temperature are reviewed, and the mechanical strength of the materials for moderator cell are discussed. It is shown that A286 is the best material for the moderator cell, and it will keep enough strength during the operational period of the cold neutron source installed in the upgraded JRR-3. (author)

  19. Radial Uniformity of neutron irradiation in silicon ingots for neutron transmutation doping at HANARO

    International Nuclear Information System (INIS)

    The radial uniformity of neutron irradiation in silicon ingots for Neutron Transmutation Doping (NTD) at HANARO is examined by both calculations and measurements. HANARO has two NTD holes named NTD1 and NTD2. We have been using the NTD2 hole for 5 in. NTD commercial service, and we intend to use two holes for 6 in. NTD. The objective of this study is to predict the radial uniformity of 6 in. NTD at the two holes. The radial neutron flux distributions inside single crystal and non-crystal silicon loaded at the NTD2 hole are calculated by the VENTURE code. For NTD1, the radial distributions of the reaction rate for a 6 in. NTD with a neutron screen are calculated by MCNP, and measured by gold wire activation. The results of the measurements are compared with those of the calculations. From the VENTURE calculation, it is confirmed that the neutron flux distribution in the single crystal silicon is much flatter than that in the non-crystal silicon. The non-uniformities of the measurements for radial neutron irradiation are slightly larger than those of the calculations. However, excluding local dips in the measurements, the overall trends of the distributions are similar. The Radial Resistivity Gradient (RRG) for a 5 in. silicon ingot is estimated to be about 1.5%. For a 6 in. ingot, the RRG of a silicon ingot irradiated at HANARO is predicted to be about 2.1%. Also, from the experimental results, we expect that the RRG would not be larger than 4.4%

  20. Accelerator technology and SPECT developments for BNCT

    International Nuclear Information System (INIS)

    Accelerator-Based BNCT (AB-BNCT) is establishing itself worldwide as the future modality to start the phase of in-hospital facilities. There are projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators. They will be briefly mentioned. In particular, the present status and recent progress of the Argentine project will be presented. The topics will cover: high power ion sources, power and voltage generation systems for a Tandem- Electrostatic Quadrupole (TES Q) accelerator, acceleration tubes, transport of intense beams, beam diagnostics, control systems, high power targets, the 9Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA.s), treatment room design, treatment planning assessment of clinical cases, etc. A complete test stand has been built and commissioned for intense proton beam production and characterization. Beams of 10 to 30 m A have been produced and transported during variable periods of operation by means of a pre accelerator and an electrostatic quadrupole doublet to a suppressed Faraday cup. The beam diagnostics has been performed through the observation with digital cameras of induced fluorescence in the residual gas. A 200 kV TES Q accelerator prototype has been constructed and tested and a 600 keV prototype is under construction. Self consistent space charge beam transport simulations have been performed and compared with experimental results. In addition to the traditional 7Li(p,n)7Be reaction, 9Be(d,n)10B using a thin Be target has been thoroughly studied as a candidate for a possible neutron source for deep seated tumors, showing a satisfactory performance. BSA.s and production targets and a treatment room complying with regulations have also been designed. Realistic clinical treatment planning cases for AB-BNCT have been studied showing very good results. Finally we will present advances in the development of a Single Photon Emission Computed Tomography (SPECT

  1. BNCT and dose fractionation

    International Nuclear Information System (INIS)

    Some portion of the radiation dose received by a patient during BNCT consists of primary and secondary gammas. The biological effect of that portion of the dose will depend upon the time history of the delivered dose. The well-known models for relating time-dose effects to clinical experience, are of questionable value in understanding dose effects in the time regime of a few hours, and for doses of less than tolerance. In order to examine the time-dose effect in the regime of interest to BNCT a simple phenomenological model was developed and normalized to the accepted body of clinical experience. The model has been applied to the question of fractionation of BNCT and the results are presented. The model is simply a linear healing model with two time constants. In other words, a first hit of radiation is assumed to wound (or potentiate) a cell. Given time, the cell will fully repair itself. If a second hit occurs before the cell has healed, the cell is killed. Apparently, there are two kinds of healing, one which occurs in 30 to 60 minutes, the other in two to four days. A small fraction of the cells will die on the first hit

  2. Decommissioning of an Irradiator MPX-γ - 25M and a neutron Irradiator

    International Nuclear Information System (INIS)

    In this paper a technology is developed with its procedures in radiation protection to ensure the safety of the process of decommissioning of two irradiators. Both processes are described, the process of decommissioning of a neutron Irradiator 4. 44·1011Bq, employed in the vegetal radio mutagenesis, and disassembling of an installation of gamma irradiation of 3.33 * 1012 Bq, self-shielded of category I, model MPX - γ - 25 M. The specific objectives are: a) identify aspects of the contractual assurance, of human and technical resources, b) to evaluate the radiological situation of the process and c) analyze the potential radiological extraordinary events in each of the steps of the process, ensuring the right answers. Evaluation of radiological successful events described can be considered as reference to address the process of disassembling of other similar irradiators

  3. Influence of neutron irradiation on conduction cooling superconducting magnets

    Science.gov (United States)

    Yang, Y.; Yoshida, M.; Ogitsu, T.; Makida, Y.; Nakamoto, T.; Okamura, T.; Sasaki, K.; Sugano, M.

    2015-12-01

    The conduction-cooled superconducting magnets are now widely used in various applications due to their minimum usage of helium. In the accelerator science, they also play an increasingly important role in particle detector solenoids because they can minimize the materials needed for the magnet such that they can be more transparent against irradiated particles. For the same reason they are currently used in high radiation environments because they can reduce the heat load from the irradiation. However, the hadronic reactions, such as neutron or proton irradiation, can create degradation on the thermal conductivity of pure aluminum which is used as a cooling path. It leads to a poor cooling condition of the magnets. In Japan, there are two conduction-cooled superconducting magnets for muon production; one is already constructed and under operation, the other is now under construction. This paper briefly reports the influence of the irradiation on those magnets and discusses the possibilities of HTS based conduction-cooled magnets under high irradiation environments.

  4. Building of scientific information system for sustainable development of BNCT in Bulgaria

    International Nuclear Information System (INIS)

    Building a boron neutron capture therapy (BNCT) facility is foreseen within the reconstruction of the Research Reactor IRT (IRT) of the Institute for Nuclear Research and Nuclear Energy of the Bulgaria Academy of Sciences (INRNE). The development of BNCT at IRT plays a very significant role in the plan for sustainable application of the reactor. A centralized scientific information system on BNCT is being built at the INRNE with the purpose to collect and sort new information as knowledge accumulated during more than thirty years history of BNCT. This BNCT information system will help the creation and consolidation of a well informed and interconnected interdisciplinary team of physicists, chemists, biologists, and radio-oncologists for establishing BNCT cancer treatment in Bulgaria. It will strengthen more intensive development of the national network as well as its enlargement to the Balkan region countries. Furthermore, to acquaint the public at large with the opportunity for BNCT cancer treatment will be addressed. Human, social, and economics results due to BNCT for many patients from Balkan region are expected.

  5. Building of scientific information system for sustainable development of BNCT in Bulgaria

    Energy Technology Data Exchange (ETDEWEB)

    Mitev, M. [Institute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences, Boul. Tsarigradsko shossee 72, Sofia (Bulgaria)], E-mail: mlmitev@inrne.bas.bg; Ilieva, K.; Apostolov, T. [Institute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences, Boul. Tsarigradsko shossee 72, Sofia (Bulgaria)

    2009-07-15

    Building a boron neutron capture therapy (BNCT) facility is foreseen within the reconstruction of the Research Reactor IRT (IRT) of the Institute for Nuclear Research and Nuclear Energy of the Bulgaria Academy of Sciences (INRNE). The development of BNCT at IRT plays a very significant role in the plan for sustainable application of the reactor. A centralized scientific information system on BNCT is being built at the INRNE with the purpose to collect and sort new information as knowledge accumulated during more than thirty years history of BNCT. This BNCT information system will help the creation and consolidation of a well informed and interconnected interdisciplinary team of physicists, chemists, biologists, and radio-oncologists for establishing BNCT cancer treatment in Bulgaria. It will strengthen more intensive development of the national network as well as its enlargement to the Balkan region countries. Furthermore, to acquaint the public at large with the opportunity for BNCT cancer treatment will be addressed. Human, social, and economics results due to BNCT for many patients from Balkan region are expected.

  6. Impurities effect on the swelling of neutron irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Donne, M.D.; Scaffidi-Argentina, F. [Institut fuer Neutronenphysik und Reaktortechnik, Karlsruhe (Germany)

    1995-09-01

    An important factor controlling the swelling behaviour of fast neutron irradiated beryllium is the impurity content which can strongly affect both the surface tension and the creep strength of this material. Being the volume swelling of the old beryllium (early sixties) systematically higher than that of the more modem one (end of the seventies), a sensitivity analysis with the aid of the computer code ANFIBE (ANalysis of Fusion Irradiated BEryllium) to investigate the effect of these material properties on the swelling behaviour of neutron irradiated beryllium has been performed. Two sets of experimental data have been selected: the first one named Western refers to quite recently produced Western beryllium, whilst the second one, named Russian refers to relatively old (early sixties) Russian beryllium containing a higher impurity rate than the Western one. The results obtained with the ANFIBE Code were assessed by comparison with experimental data and the used material properties were compared with the data available in the literature. Good agreement between calculated and measured values has been found.

  7. Radioactivity of neutron-irradiated cat's-eye chrysoberyls

    Science.gov (United States)

    Tang, S. M.; Tay, T. S.

    1999-04-01

    The recent report of marketing of radioactive chrysoberyl cat's-eyes in South-East Asian markets has led us to use an indirect method to estimate the threat to health these color-enhanced gemstones may pose if worn close to skin. We determined the impurity content of several cat's-eye chrysoberyls from Indian States of Orissa and Kerala using PIXE, and calculated the radioactivity that would be generated from these impurities and the constitutional elements if a chrysoberyl was irradiated by neutrons in a nuclear reactor for color enhancement. Of all the radioactive nuclides that could be created by neutron irradiation, only four ( 46Sc, 51Cr, 54Mn and 59Fe) would not have cooled down within a month after irradiation to the internationally accepted level of specific residual radioactivity of 2 nCi/g. The radioactivity of 46Sc, 51Cr and 59Fe would only fall to this safe limit after 15 months and that of 54Mn could remain above this limit for several years.

  8. Protocols for BNCT of glioblastoma multiforme at Brookhaven: Practical considerations

    Energy Technology Data Exchange (ETDEWEB)

    Chanana, A.D.; Coderre, J.A.; Joel, D.D.; Slatkin, D.N.

    1996-12-31

    In this report we discuss some issues considered in selecting initial protocols for boron neutron capture therapy (BNCT) of human glioblastoma multiforme. First the tolerance of normal tissues, especially the brain, to the radiation field. Radiation doses limits were based on results with human and animal exposures. Estimates of tumor control doses were based on the results of single-fraction photon therapy and single fraction BNCT both in humans and experimental animals. Of the two boron compounds (BSH and BPA), BPA was chosen since a FDA-sanctioned protocol for distribution in humans was in effect at the time the first BNCT protocols were written and therapy studies in experimental animals had shown it to be more effective than BSH.

  9. Calculation of neutron spectra on typical irradiation location of the CFBR-II reactor

    International Nuclear Information System (INIS)

    Neutron energy spectra were simulated by the MCNP code. The neutron energy spectra and corresponding average energy of off-coupling box, irradiation channel and outer surface of the off-coupling cover were calculated. The results indicate that about 90% neutrons are in the energy range of 0.05-3 MeV. The average neutron energy of off-coupling box and irradiation channel present 'S' shape along distance, and space asymmetry must be considered. The average neutron energy above off-coupling cover's 45 degree woof fluctuates slightly and it is an appropriate irradiation area. (authors)

  10. Present status and prospects of medical irradiation in JAERI

    International Nuclear Information System (INIS)

    A medical irradiation facility for Boron Neutron Capture Therapy (BNCT) was installed at JRR-2 in August 1990. Thermal neutron flux at beam port is about 1x109 n/cm2/s. Since then 28 cases of medical irradiation were performed in five years for clinical trials of BNCT for malignant brain tumor patients. The experiences of medical irradiation and dose monitoring are described. The operation of JRR-4 using HEU fuel terminated at the beginning of 1996. A new medical irradiation facility will be installed and the utilization operation of the reactor will be resumed with LEU fuel in the first half of 1998. Recent years a significant progress have been achieved in the field of BNCT using epithermal neutron beam in the USA and Europe. The new facility at JRR-4 is planned to be capable of providing both thermal and epithermal beams. The design of the multi-mode facility and the result of the performance analysis are presented. (author)

  11. IRT-Sofia BNCT beam tube optimization study

    International Nuclear Information System (INIS)

    An optimization study of IRT-Sofia BNCT beam tube is presented. In the study we used the MIT/FCB experience. The enlarging of filter/moderator cross section dimensions and the decreasing of collimator length within the limits of the IRT-Sofia reactor design were analyzed. The influence of beam and reactor core axes non-coincidence on the beam properties was also evaluated. The irradiation resistance of polytetrafluoroethylene (Teflon®) was also evaluated. The results provide information for making decisions on the IRT-Sofia BNCT beam construction.

  12. IRT-Sofia BNCT beam tube optimization study

    Energy Technology Data Exchange (ETDEWEB)

    Belousov, S., E-mail: belousov@inrne.bas.bg [Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Tsarigradsko 72, Sofia (Bulgaria); Mitev, M.; Ilieva, K. [Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Tsarigradsko 72, Sofia (Bulgaria); Riley, K. [Radiation Monitoring Devices, Watertown, MA (United States); Harling, O. [Nuclear Science and Engineering Department, Massachusetts Institute of Technology, Cambridge, MA (United States)

    2011-12-15

    An optimization study of IRT-Sofia BNCT beam tube is presented. In the study we used the MIT/FCB experience. The enlarging of filter/moderator cross section dimensions and the decreasing of collimator length within the limits of the IRT-Sofia reactor design were analyzed. The influence of beam and reactor core axes non-coincidence on the beam properties was also evaluated. The irradiation resistance of polytetrafluoroethylene (Teflon{sup Registered-Sign }) was also evaluated. The results provide information for making decisions on the IRT-Sofia BNCT beam construction.

  13. Crystallographic changes in lead zirconate titanate due to neutron irradiation

    Directory of Open Access Journals (Sweden)

    Alexandra Henriques

    2014-11-01

    Full Text Available Piezoelectric and ferroelectric materials are useful as the active element in non-destructive monitoring devices for high-radiation areas. Here, crystallographic structural refinement (i.e., the Rietveld method is used to quantify the type and extent of structural changes in PbZr0.5Ti0.5O3 after exposure to a 1 MeV equivalent neutron fluence of 1.7 × 1015 neutrons/cm2. The results show a measurable decrease in the occupancy of Pb and O due to irradiation, with O vacancies in the tetragonal phase being created preferentially on one of the two O sites. The results demonstrate a method by which the effects of radiation on crystallographic structure may be investigated.

  14. Status of Neutron Irradiation of Non-Nuclear Materials at HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Kee-Nam; Cho, Man-Soon; Shin, Yoon-Taek; Park, Seng-Jae; Kang, Young Hwan; Jun, Byung-Hyuk; Kim, Chan-Joong; Park, Sang-Jun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    The irradiation facilities have been mostly utilized for the KAERI nuclear research projects relevant to a commercial nuclear power reactor such as the ageing management and safety evaluation of the components. Based on the accumulated experience, HANARO has recently supported national R and D projects relevant to new nuclear systems including the System-integrated Modular Advanced Reactor (SMART), research reactors, and future nuclear systems. As neutron irradiation affects the structure of a material, radiation induced modification of materials has become a perspective method for the purposeful changes in material properties. Some irradiation tests of electro-magnetic materials were also performed at HANARO for scientific research of universities and the demand for neutron irradiation of the materials is increasing rapidly. Another research reactor that will specialize in radio-isotope and neutron transmutation doping (NTD) Si production and the demonstration of reactor design is under construction in Korea. Therefore, HANARO will specialize more on irradiation research. Based on its accumulated irradiation experience, HANARO has recently started new support of R and D relevant to the irradiation of electro-magnetic materials. In this paper, the status of utilization of the HANARO irradiation facilities for non-nuclear materials and the possibility of researches on new electro-magnetic materials using neutron irradiation are surveyed to encourage the utilization of HANARO. HANARO irradiation facilities have been actively utilized for various material irradiation tests requested by users. Although most irradiation tests have been related to national R and D relevant to nuclear power, demand for neutron irradiation of electro-magnetic materials is rapidly increasing at HANARO. Another research reactor, the KIJANG research reactor (KJRR), is under construction in Korea. New irradiation facilities including Neutron Transmutation Doping (NTD) facilities for power

  15. Status of Neutron Irradiation of Non-Nuclear Materials at HANARO

    International Nuclear Information System (INIS)

    The irradiation facilities have been mostly utilized for the KAERI nuclear research projects relevant to a commercial nuclear power reactor such as the ageing management and safety evaluation of the components. Based on the accumulated experience, HANARO has recently supported national R and D projects relevant to new nuclear systems including the System-integrated Modular Advanced Reactor (SMART), research reactors, and future nuclear systems. As neutron irradiation affects the structure of a material, radiation induced modification of materials has become a perspective method for the purposeful changes in material properties. Some irradiation tests of electro-magnetic materials were also performed at HANARO for scientific research of universities and the demand for neutron irradiation of the materials is increasing rapidly. Another research reactor that will specialize in radio-isotope and neutron transmutation doping (NTD) Si production and the demonstration of reactor design is under construction in Korea. Therefore, HANARO will specialize more on irradiation research. Based on its accumulated irradiation experience, HANARO has recently started new support of R and D relevant to the irradiation of electro-magnetic materials. In this paper, the status of utilization of the HANARO irradiation facilities for non-nuclear materials and the possibility of researches on new electro-magnetic materials using neutron irradiation are surveyed to encourage the utilization of HANARO. HANARO irradiation facilities have been actively utilized for various material irradiation tests requested by users. Although most irradiation tests have been related to national R and D relevant to nuclear power, demand for neutron irradiation of electro-magnetic materials is rapidly increasing at HANARO. Another research reactor, the KIJANG research reactor (KJRR), is under construction in Korea. New irradiation facilities including Neutron Transmutation Doping (NTD) facilities for power

  16. Dislocation and void segregation in copper during neutron irradiation

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Leffers, Torben; Horsewell, Andy

    1986-01-01

    High-purity (99. 999%) and fully annealed copper specimens have been irradiated in the DR-3 reactor at Riso to doses of 1 multiplied by 10**2**2 and 5 multiplied by 10**2**2 neutrons (fast)m** minus **2(2 multiplied by 10** minus **3 dpa and 1 multiplied by 10** minus **2 dpa, respectively); the ...... density, the void swelling rate was very high (approximately 2. 5% per dpa). The implications of the segregated distribution of sinks for void formation and growth are briefly discussed....

  17. Gamma and neutron irradiation tests on commercial IC op amps

    International Nuclear Information System (INIS)

    Experimental results of gamma and neutron irradiation tests on 30 types of integrated-circuit operational amplifiers from 11 manufacturers are presented. All units were low-cost, commercial-grade devices. Op amps were evaluated for changes in offset voltage, input bias current, power supply current, open-loop gain, gain-bandwidth product, slew rate, power-supply and common-mode rejection ratios. Bipolar transistor op amps with resistive collector load resistors for the input stage indicated the best radiation hardness

  18. Neutron generation by laser irradiation of CD4 clusters

    International Nuclear Information System (INIS)

    It was shown in 1999 that D2 cluster explosion under ultrashort intense laser irradiation can lead to ion energies sufficient to drive nuclear fusion reactions [Ditmire et al. Nature 398, 491]. We show how the use of molecular clusters allows to further enhance the ionic acceleration, allowing one to reach optimal fusion cross sections. A new low density high energy regime is described, in which fusion occurs via a spallation-like process. The process increases with laser intensity up to the relativistic threshold, at which the neutron production is overwhelmed by gamma production resulting from electron acceleration

  19. Optimization of the application of BNCT to undifferentiated thyroid cancer

    International Nuclear Information System (INIS)

    The possible increase in BNCT efficacy for undifferentiated thyroid carcinoma (UTC) using BPA plus BOPP and nicotinamide (NA) as a radiosensitizer on the BNCT reaction was analyzed. In these studies nude mice were transplanted with the ARO cells and after 14 days they were treated as follows: 1) Control; 2) NCT (neutrons alone); 3) NCT plus NA (100 mg/kg bw/day for 3 days); 4) BPA (350 mg/kg bw) + neutrons; 5) BPA+ NA+ neutrons; 6) BPA+BOPP (60 mg/kg bw) + neutrons. The flux of hyperthermal neutrons was 2.8 108 during 85 min. Neutrons alone or with NA caused some tumor growth delay, while in the BPA, BPA+NA and BPA+BOPP groups a 100% halt of tumor growth was observed. When the initial tumor volume was 50 mm3 or less a complete cure was found in BPA+NA (2/2); BPA (1/4); BPA+BOPP (7/7). After 90 days of complete regression, recurrence of tumor was observed in 2/2 BPA/NA (2/2) and BPA+BOPP (1/7). Caspase 3 activity was increased in BPA+NA (p<0.05 vs controls). BPA plus NA increased tumor apoptosis but only the combination of BPA+BOPP increased significantly BNCT efficiency. (author)

  20. Report of the workshop on low-temperature neutron irradiation

    International Nuclear Information System (INIS)

    This Workshop was held at Oak Ridge National Laboratory May 29-31, 1985, to aid in preparing for the use of the National Low-Temperature Neutron Irradiation Facility (NLTNIF), which is being built at the Bulk Shielding Reactor at Oak Ridge National Laboratory and is scheduled to be ready for experiments late in 1985. NLTNIF will be operated as a user facility, with no cost to users for the irradiations for approved experiments. Purposes of the Workshop were to review research areas for which NLTNIF can be used, and to provide necessary experimental details about the facility for potential users. One day consisted of a series of presentations on scientific topics relevant to NLTNIF. Summaries of these talks are included in this report

  1. Phase transformations in lithium aluminates irradiated with neutrons

    International Nuclear Information System (INIS)

    The lithium aluminate like candidate to be used in the coverings producers of tritium in the fusion nuclear reactors, presents high resistance to the corrosion to the one to be stuck to structural materials as special steels. However, the crystallographic changes that take place in the cover that is continually subjected to irradiation with neutrons, can alter its resistance to the corrosion. In this work the changes of crystalline structure are shown that they present two types of nano structures of lithium aluminates, subjected to an average total dose 7.81 x 108 Gy in the fixed irradiation system of capsules of the one TRIGA Mark lll nuclear reactor of the Nuclear Center of Mexico. The studied nano structures presented only phase transformations without formation of amorphous material. (Author)

  2. Development of an accelerator based BNCT facility. Following the Ibaraki BNCT project development process

    International Nuclear Information System (INIS)

    An accelerator-based BNCT (Boron Neutron Capture Therapy) facility is being constructed at the Ibaraki Neutron Medical Research Center. It consists of a proton linac (8 MeV energy and 10 mA average current), a beryllium target, and a moderator system to provide an epi-thermal neutron flux for patient treatment. The technology choices for this present system were driven by the need to site the facility in a hospital and where low residual activity is essential. The maximum neutron energy produced from an 8 MeV-proton is 6 MeV, which is below the threshold energy of the main nuclear reactions which produce radioactive products. The down side of this technology choice is that it produces a high density heat load on the target so that cooling and hydrogen blistering amelioration prevent sever challenges requiring successful R and D progress. The latest design of the target and moderator system shows that a flux of 2.5x109 epi-thermal neutrons/cm2/sec can be obtained. This is two times higher than the flux from the existing nuclear reactor based BNCT facility at JAEA (JRR-4). (author)

  3. Hole mobility in germanium irradiated with large fluences of fast neutrons

    International Nuclear Information System (INIS)

    The Hall mobility of holes in germanium irradiated with large fluences of fast neutrons 1014 cm-219 cm-2 is studied over a wide range of temperature 7 K14 cm-3RD17 cm-3. After irradiation the original samples became p-type, low-resistance samples. Electrical properties of neutron irradiated germanium are determined by acceptor-like radiation defects with energy levels of EV+0.016 eV. It is found that at temperatures above 100 K the hole mobility in neutron irradiated germanium and in germanium doped by gallium changes with temperature by general laws, and their values are comparable. The main scattering mechanisms inherent to homogeneous doped crystalline semiconductors are established also in neutron irradiated germanium. The results give rise to conclude that germanium irradiated with large fluences of fast neutrons can be assumed as crystalline with a homogeneous radiation defect distribution. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  4. Optimization of thermal neutron flux in an irradiator assembly with different isotopic sources

    International Nuclear Information System (INIS)

    Highlights: • The aim of this work, is to evaluate the thermal neutron distribution in an irradiator assembly. • Thermal neutron distribution were determined experimentally and calculated by MCNP. • The calculated and experimental results were in good agreement. - Abstract: This work aimed to determine the distribution of thermal neutron flux in an irradiator assembly to study the possibility of use this irradiator for Neutron Activation Analysis; NAA. To establish the facility specifications, the thermal neutron flux values of 252Cf and Pu-Be isotopic neutron sources along the horizontal irradiator axis were determined experimentally and calculated by Monte Carlo N-Particle; MCNP transport code. The irradiator assembly characterized by supplying a stable neutron flux for a long period, eliminating the need to use standard material i.e. comparative method, so that the process becomes efficient, compact, economical and more reliable. The measurements were carried out at different position inside the irradiator assembly using proportional 3He-detector and gold foil activation method. As well as, these measurements were performed without and with two types of neutron reflector such as water and steel to determine the thermal neutron distribution along the irradiation points. The experimental results were compared to the calculations performed with MCNP Code. The calculated and experimental results were in reasonable agreement for both 252Cf and Pu-Be sources. This indicated that the material and geometrical properties of the irradiator were modeled well

  5. Hydrides formation In Zircaloy-4 irradiated with neutrons

    International Nuclear Information System (INIS)

    Under reactor operating conditions zirconium components go through transformations which affect their original properties. Two phenomena of significant consequences for the integrity of the components are hydrogen uptake and radiation damage, since both contribute to the material fragilization. In the case of the Atucha I nuclear power reactor, the cooling channels, Zircaloy-4 tubular structural components about 6 meters long, were designed to withstand the entire lifetime of the reactor. Inside them, fuel elements 5.3 meters long are located. The fuel elements are cooled by a heavy water flow which circulates from the bottom (250o) to the top of the reactor (305oC). The channels are affected by a fast neutron flux (En>1 Mev), increasing from a nominal value of 1.35 x 1013 neutrons/cm2 sec at the bottom to 1.69 x 1013 neutrons/cm2 sec at the top, reaching a maximum value of 3.76 x 1013 neutrons/cm2 sec at the center of the channels. However, due to the reactor operating conditions, they are replaced after about 10 effective full power years, time at which they reach 1022 neutrons/cm2 at the most neutronically active regions of the reactor. Studies on cooling channels are meaningful from many points of view. The channels are structural components which do not work under internal pressure or any other type of structural stress. The typical temperature of the cladding tubes in the reactor is about 350oC, at which many types of irradiation defects are annealed [1]. The temperature range of the cooling channels lies between 200oC-235oC (outer foil of the channels) and 260oC-300oC (internal tube), a difference which makes the defect recovery kinetics slower. In the present context, following the program developed in the research contract 15810, we continue with the work started on the effects of the radiation on the hydride formation focusing on the dislocation loops in the zirconium matrix and its possible role as preferential sites for hydride precipitation. The

  6. Radiation damage in stainless steel under varying temperature neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Naoaki [Kyushu Univ., Kasuga, Fukuoka (Japan). Research Inst. for Applied Mechanics

    1998-03-01

    Microstructural evolution of model alloys of 316SS was examined by neutron irradiation at JMTR under cyclic temperature varying condition. In the case of Fe-16Cr-17Ni, formation of interstitial loops and voids are strongly suppressed by varying the temperature from 473K to 673K. By adding Ti as miner element (0.25wt%), however, abnormal accumulation of vacancies (void swelling of 11%dpa at 0.1dpa) was observed. Theoretical analysis standing on the rate theory of defect clustering and simulation irradiation experiments with heavy ions indicates that the vacancy-rich condition which appears temporally during and after changing the temperature from low to high brings these results. It was also shown that only 1 dpa pre-irradiation at low temperature changes swelling behavior at high temperature above several 10 dpa. The understanding of non-steady-state defect processes under temperature varying irradiation is very important to estimate the radiation damage under fusion environment where short-term and long-term temperature variation is expected. (author)

  7. Fracture mechanics behaviour of neutron irradiated Alloy A-286

    International Nuclear Information System (INIS)

    The effect of fast-neutron irradiation on the fatigue-crack propagation and fracture toughness behaviour of Alloy A-286 was characterized using fracture mechanics techniques. The fracture toughness was found to decrease continuously with increasing irradiation damage at both 24 deg. C and 427 deg. C. In the unirradiated and low fluence conditions, specimens displayed appreciable plasticity prior to fracture, and equivalent Ksub(Ic) values were determined from Jsub(Ic) fracture toughness results. At high irradiation exposure levels, specimens exhibited a brittle Ksub(Ic) fracture mode. The 427 deg. C fracture toughness fell from 129 MPa√m in the unirradiated condition to 35 MPa√m at an exposure of 16.2 dpa (total fluence of 5.2x1022n/cm2). Room temperature fracture toughness values were consistently 40 to 60 percent higher than the 427 deg. C values. Electron fractography revealed that the reduction in fracture resistance was attributed to a fracture mechanism transition from ductile microvoid coalescence to channel fracture. Fatigue-crack propagation tests were conducted at 427 deg. C on specimens irradiated at 2.4 dpa and 16.2 dpa. Crack growth rates at the lower exposure level were comparable to those in unirradiated material, while those at the higher exposure were slightly higher than in unirradiated material. (author)

  8. Void formation in neutron-irradiated Cu and Cu alloys

    International Nuclear Information System (INIS)

    Pure copper and copper-aluminium alloys were neutron-irradiated at high temperatures in the as-received condition, and after being melted under high vacuum or in argon. Melting under high vacuum was done to reduce the residual gas amount in the specimens. The number density of voids in the vacuum-melted Cu was one tenth of that in as-received Cu after JMTR irradiation to 5.2 x 1024 n/m2 at 603 K. Similarly, voids were also formed in an argon-melted Cu-1at%Al specimen but were not formed in a vacuum-melted one. Following higher dose irradiation in the JOYO reactor, nearly the same number density and size of voids were formed in both argon and vacuum-melted Cu. In Cu-5at%Al, many voids were formed in argon-melted specimens, whereas in vacuum-melted specimens voids were not formed. These results show that voids nucleate at vacancy clusters which trap gas atoms. In the JOYO irradiation, diffused-in gas atoms play an important role in the formation of voids in Cu. In Cu-5at%Al, diffused-in gas atoms were trapped by Al atoms, resulting in a difference of void formation between the two types of specimens. (orig.)

  9. Proton nuclear magnetic resonance measurement of p-boronophenylalanine (BPA): A therapeutic agent for boron neutron capture therapy

    OpenAIRE

    Zuo, C. S.; Prasad, P V; Busse, Paul; L. Tang; Zamenhof, R. G.

    1999-01-01

    Noninvasive in vivo quantitation of boron is necessary for obtaining pharmacokinetic data on candidate boronated delivery agents developed for boron neutron capture therapy (BNCT). Such data, in turn, would facilitate the optimization of the temporal sequence of boronated drug infusion and neutron irradiation. Current approaches to obtaining such pharmacokinetic data include: positron emission tomography employing F-18 labeled boronated delivery agents (e.g., p-boronophenylalanine), ex vivo n...

  10. Radiation-induced meningiomas after BNCT in patients with malignant glioma.

    Science.gov (United States)

    Kageji, T; Sogabe, S; Mizobichi, Y; Nakajima, K; Shinji, N; Nakagawa, Y

    2015-12-01

    Of the 180 patients with malignant brain tumors whom we treated with boron neutron capture therapy (BNCT) since 1968, only one (0.56%) developed multiple radiation-induced meningiomas. The parasagittal meningioma that had received 42 Gy (w) for BNCT showed more rapid growth on Gd-enhanced MRI scans and more atypical features on histopathologic studies than the temporal convexity tumor that had received 20 Gy (w). Long-term follow up MRI studies are necessary in long-survivors of malignant brain tumors treated by BNCT. PMID:26122975

  11. Prematurely condensed chromosome rings after neutron irradiation of human lymphocytes

    International Nuclear Information System (INIS)

    Calibration curves for fission spectrum neutrons and other high linear energy transfer (LET) radiations are scarce in cytogenetic dosimetry and particularly for Prematurely Condensed Chromosome Rings (PCC-ring). Here we analyzed the behavior of the PCC-ring frequency and PCC index after neutron irradiation in a broad dose interval from 1 to 26 Gy. PCC-rings were induced in lymphocytes with Calyculin A. 6455 PCC cells in G1, G2/M and M/A stages were analyzed. The best fitting between the frequency of PCC ring (Y) and the Dose (D) was obtained with the equation Y= (0.059±0.003) D. The saturation of the PCC-ring was observed after around 4 Gy, but it was still possible to analyze cells exposed up to 26 Gy. The distribution of rings by cell follows Poisson or Neyman type distribution for all doses. This PCC-ring dose effect curve can be used in case of accidental overexposure to neutron radiation, allowing a dose assessment in a reliable way. Additionally, the PCC index seems to be well correlated with radiation dose and decrease in a dose dependent manner from 13% in non exposed sample down to 0.2%. This observation allows the possibility to perform a quick classification of victims exposed to high doses of both gamma and neutron radiations. The PCC assay can then be used for both neutron dose estimation up to 4 Gy and for the rapid classification of victims exposed to higher doses. This assay could be included in the multiparametric approach developed to optimize the medical treatment of radiation victims. (author)

  12. The radiobiology of boron neutron capture therapy: Are ''photon-equivalent'' doses really photon-equivalent?

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) produces a mixture of radiation dose components. The high-linear energy transfer (LET) particles are more damaging in tissue than equal doses of low-LET radiation. Each of the high-LET components can multiplied by an experimentally determined factor to adjust for the increased biological effectiveness and the resulting sum expressed in photon-equivalent units (Gy-Eq). BNCT doses in photon-equivalent units are based on a number of assumptions. It may be possible to test the validity of these assumptions and the accuracy of the calculated BNCT doses by 1) comparing the effects of BNCT in other animal or biological models where the effects of photon radiation are known, or 2) if there are endpoints reached in the BNCT dose escalation clinical trials that can be related to the known response to photons of the tissue in question. The calculated Gy-Eq BNCT doses delivered to dogs and to humans with BPA and the epithermal neutron beam of the Brookhaven Medical Research Reactor were compared to expected responses to photon irradiation. The data indicate that Gy-Eq doses in brain may be underestimated. Doses to skin are consistent with the expected response to photons. Gy-Eq doses to tumor are significantly overestimated. A model system of cells in culture irradiated at various depths in a lucite phantom using the epithermal beam is under development. Preliminary data indicate that this approach can be used to detect differences in the relative biological effectiveness of the beam. The rat 9L gliosarcoma cell survival data was converted to photon-equivalent doses using the same factors assumed in the clinical studies. The results superimposed on the survival curve derived from irradiation with Cs-137 photons indicating the potential utility of this model system. (author)

  13. Modeling of irradiation hardening of iron after low-dose and low-temperature neutron irradiation

    International Nuclear Information System (INIS)

    Irradiation hardening is a prominent low-temperature degradation phenomena in materials, and is characterized both by an irradiation-induced increase in yield strength along with the loss of ductility. In this paper, a reaction–diffusion cluster dynamics model is used to predict the distribution of vacancy and interstitial clusters in iron following low-temperature (<373 K) and low-dose (<0.1 dpa) neutron irradiation. The predicted microstructure evolutions of high-purity iron samples are compared to published experimental data (positron annihilation spectroscopy and transmission electron microscopy) and show good agreement for neutron irradiation in this regime. The defect cluster distributions are then coupled to a dispersed barrier hardening model that assumes a strength factor, α, which varies with cluster type and size to compute the yield strength increase; the results of which agree reasonably well with tensile tests performed in previous studies. The modeling results presented here compare quite well to the experimental observations in the low-dose regime, and provide insight into the underlying microstructure–property relationships and the need for spatially dependent modeling to accurately predict the saturation behavior of yield strength changes observed experimentally at higher dose levels. (paper)

  14. Tumor growth suppression by boron neutron capture therapy using PEG-liposomal boron delivery in vivo

    International Nuclear Information System (INIS)

    The tumor cell destruction in boron neutron-capture therapy (BNCT) is due to the nuclear reaction between 10B and thermal neutrons. We prepare a polyethylene glycol (PEG) binding liposome (DPPC/cholesterol/DSPC-PEG2000) entrapped 10B compound for the delivery system. We evaluated the cytotoxic effects of intravenously injected 10B-PEG-liposome on human pancreatic carcinoma (AsPC-1) xenografts in nude mice with thermal neutron irradiation. After thermal neutron irradiation of mice injected with 10B-bare liposome or 10B-PEG-liposome, AsPC-1 tumour growth was suppressed relative to controls. Injection of 10B-PEG-liposome caused the greatest tumour suppression with thermal neutron irradiation in vivo. These results suggests that intravenous injection of 10B-PEG-liposome can increase the retention of 10B atoms by tumor cells, causing tumor growth suppression in vivo upon thermal neutron irradiation. (author)

  15. Use of Neutron Irradiations in the Brookhaven Mutations Programme

    International Nuclear Information System (INIS)

    The Co-operative Radiation-Mutations Programme was established at Brookhaven National Laboratory approximately ten years ago to enable plant breeders and agriculturalists to make use of irradiation techniques in plant improvement programmes. The radiation facilities used in the programme are the thermal neutron column at the BGRR reactor, the 250-kVp X-ray machine in the Biology Department, the kilocurie gamma-sources in the Nuclear Engineering Department, a 12 c Co60 gamma-source in the greenhouse, and a 4000 c Co60 source located in a 13-acre field. The development of facilities, techniques, and theory represent Brookhaven's role in this cooperative project whereas the plant material and seed are provided by agricultural experts who are responsible for growing the irradiated material and screening for mutations. More than 150 scientists in 45 states and Puerto Rico are availing themselves of the programme's facilities. Projects have also initiated with Australia, Belgium, Chile, Costa Rica, Denmark, Ecuador, Formosa, Greece, Guatemala, India, Ireland, Italy, Japan, Kenya, Mexico, the Netherlands, Pakistan, Peru, the Philippines, Romania, South Africa.Thailand, Venezuela, West Germany and Yugoslavia. A review of the above cc-operative projects is presented with emphasis on the use of neutrons in mutation induction. (author)

  16. The effect of neutron irradiation on silicon carbide fibers

    International Nuclear Information System (INIS)

    Nine types of SiC fiber have been exposed to neutron radiation in the Advanced Test Reactor at 250 C for various lengths of time ranging from 83 to 128 days. The effects of these exposures have been initially determined using scanning electron microscopy. The fibers tested were Nicalon trademark CG, Tyranno, Hi-Nicalon trademark, Dow Corning SiC, Carborundum SiC, Textron SCS-6, polymethysilane (PMS) derived SiC from the University of Michigan, and two types of MER SiC fiber. This covers a range of fibers from widely used commercial fibers to developmental fibers. Consistent with previous radiation experiments, Nicalon fiber was severely degraded by the neutron irradiation. Similarly, Tyranno suffered severe degradation. The more advanced fibers which approach the composition and properties of SiC performed well under irradiation. Of these, the Carborundum SiC fiber appeared to perform the best. The Hi-Nicalon and Dow Corning Fibers exhibited good general stability, but also appear to have some surface roughening. The MER fibers and the Textron SCS-6 fibers both had carbon cores which adversely influenced the overall stability of the fibers

  17. Electroporation increases the effect of borocaptate (10B-BSH) in neutron capture therapy

    International Nuclear Information System (INIS)

    Purpose: The cell membrane permeability of borocaptate (10B-BSH) and its extent of accumulation in cells are controversial. This study was performed to elucidate these points. Methods and Materials: Two different treatments were applied to SCCVII tumor cells. The first group of tumor cells was incubated in culture medium with 10B-BSH or 10B-enriched boric acid, and was exposed to neutrons from the heavy water facility of the Kyoto University Reactor (KUR). More than 99% of neutrons were thermal neutrons at flux base. The second group was pretreated by electroporation in combination with 10B-BSH, and thereafter the cells were irradiated with neutrons. The cell killing effects of boron neutron capture therapy (BNCT) using BSH were investigated by colony formation assay. Results: Surviving cell fraction decreased exponentially with neutron fluence, and addition of BSH significantly enhanced the cell killing effect of neutron capture therapy (NCT) depending on 10B concentration. The effect of BSH-BNCT also increased with preincubation time of cells in the medium containing BSH. The electroporation of cells with BSH at 10 ppm 10B markedly enhanced BSH-BNCT effects in comparison with that of preincubation alone. The effect of BSH-BNCT with electroporation was equal to that of BNCT using 10B-boric acid at a same 10B concentration (10 ppm). Conclusions: BSH is suggested to penetrate the cells slowly and remained after washing. Electroporation can introduce BSH into the cells very efficiently, and BSH stays in the cells and is not lost by washing. Therefore, if electroporation is applied to tumors after BSH injection, 10B remains in tumors but is cleared from normal tissues, and selective accumulation of 10B in tumors will be achieved after an adequate waiting time

  18. Behavior of hydrogen in neutron-irradiated stainless steels

    International Nuclear Information System (INIS)

    Full text: Measurements of angular distribution of annihilation photons (ADAP) are applied to investigations of structure defects and hydrogen behavior in annealed, plastically deformed, and irradiated stainless steels. The subjects of research were two chromium-nickel austenitic steels marked as 10Kh18N10T-Vd (Ep - 502) and Kh15N28B2M4B (Ep - 485), and for comparison purposes, nickel-free ferritic steel 1Kh13M2S2 (Ei - 852), initial state of which were provided by annealing under the temperature of 1050 deg. C during 1.5 hours in vacuum of 10-5 Pa. Preliminary degree of cold deformation was equalled to e = 10%. Hydrogen saturation was carried out according to the Siverts method under the temperature of T = 500 deg. C during 1 hour. Neutron irradiation was conducted up to the fluence range of 1022 M-2 under T≤80 deg.C. Investigation of materials was realized by the method of measuring spectra of angular correlation of two quantum annihilation radiation nascent as a result of interaction of slow positron with electrons. As a positron source The isotope 22Na was chosen with activity equalled to 10 MCi (3.7·108 Bq). Angular resolution of the plant amounted to 0.5 Mrad, and time resolution - about 0.5 ms. Statistical accuracy in the maximum of spectrum was not worse than 0.5%. The main parameters of annihilation are reflected in the table 1. For simplification reasons, in the column 'Condition of materials' of The Table The following abbreviations were used: AC - Annealed Condition; E = 10 % or e10 - Plastic deformation by 10%; H or H500 - hydrogen pick-up under T = 500 deg. C; N0 - irradiation by neutrons; as well as their appropriate combinations in these processes interchange. It is determined that the whole cycle of investigation performed with use of the method of positron diagnostics helped tracing the formation and evolution of defect structure and hydrogen behavior in different kinds of steel in complex physical-mechanical influences concerned with plastic

  19. Dosimetric feasibility study for an extracorporeal BNCT application on liver metastases at the TRIGA Mainz.

    Science.gov (United States)

    Blaickner, M; Kratz, J V; Minouchehr, S; Otto, G; Schmidberger, H; Schütz, C; Vogtländer, L; Wortmann, B; Hampel, G

    2012-01-01

    This study investigates the dosimetric feasibility of Boron Neutron Capture Therapy (BNCT) of explanted livers in the thermal column of the research reactor in Mainz. The Monte Carlo code MCNP5 is used to calculate the biologically weighted dose for different ratios of the (10)B-concentration in tumour to normal liver tissue. The simulation results show that dosimetric goals are only partially met. To guarantee effective BNCT treatment the organ has to be better shielded from all gamma radiation. PMID:21872481

  20. Genes involved in yeast survival after irradiation with fast neutrons

    International Nuclear Information System (INIS)

    Life on the Earth has evolved against a continuous background of ionizing radiation. It would be expected, therefore, that all possible mutations have been produced at some time or another; man-made radiation from medical or industrial sources will not result in any new types of mutation but will simply increase the whole spectrum of mutations that occur spontaneously. Any such lesion can be mutagenic and, in principle, lethal. To counteract the consequences of DNA damage, evolution has equipped all living cells with an intricate network of defense and repair systems. Together, these systems act as a kind of nuclear 'immune system' that is able to recognize and eliminate many types of DNA lesions. In the case of the yeast Saccharomyces cerevisiae, in these processes over 30 RAD genes participate. We tested the survival of haploid and diploid rad1 yeast mutant strains at a dose of 15 Gy of γ or fast neutron radiation. We demonstrated that the lethality of rad1 mutants both haploid and diploid are significantly higher after fast neutron irradiation. The results indicate to the role and position of these genes in the DNA repair of damages specifically induced by fast neutrons. (authors)