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Journal Articles

Study of charged particle activation analysis, 2; Determination of boron concentration in human blood samples

Ikebe, Yurie*; Oshima, Masumi*; Bamba, Shigeru*; Asai, Masato; Tsukada, Kazuaki; Sato, Tetsuya; Toyoshima, Atsushi*; Bi, C.*; Seto, Hirofumi*; Amano, Hikaru*; et al.

Applied Radiation and Isotopes, 164, p.109106_1 - 109106_7, 2020/10

Boron Neutron Capture Therapy (BNCT) is a radiotherapy for the treatment of intractable cancer. In BNCT precise determination of $$^{10}$$B concentration in whole blood sample before neutron irradiation is crucial for control of the neutron irradiation time and the neutron dosimetry. We have applied the Charged Particle Activation Analysis (CPAA) to non-destructive and accurate determination of $$^{10}$$B concentration in whole blood sample. The experiment was performed at JAEA Tandem Accelerator using an 8 MeV proton beam. The 478 keV $$gamma$$ ray of $$^{7}$$Be produced in the $$^{10}$$B(p,$$alpha$$)$$^{7}$$Be reaction was used to quantify the $$^{10}$$B, and $$gamma$$ rays of $$^{56}$$Co originating from the reaction with Fe in blood was used to normalize the $$gamma$$-ray intensity. The results demonstrated that the present CPAA method can be applied to the determination of the $$^{10}$$B concentration in the blood sample.

Journal Articles

Evaluation of RBE-weighted doses for various radiotherapy beams based on a microdosimetric function implemented in PHITS

Takada, Kenta*; Sato, Tatsuhiko; Kumada, Hiroaki*; Sakurai, Hideyuki*; Sakae, Takeji*

Journal of Physics; Conference Series, 1662, p.012004_1 - 012004_6, 2020/10

The University of Tsukuba has developed a treatment planning system (TPS) for boron neutron capture therapy (BNCT) that uses a Monte Carlo algorithm as a dose calculation engine. In the system, RBE-weighted dose can be also estimated using the microdosimetric function implemented in PHITS. In this study, we calculated the RBE-weighted doses for various radiation therapy beams. Comparison between the calculated results for different radiation therapy beams as well as verification of the calculated data will be presented at the meeting.

Journal Articles

Depth distributions of RBE-weighted dose and photon-isoeffective dose for boron neutron capture therapy

Sato, Tatsuhiko; Masunaga, Shinichiro*; Kumada, Hiroaki*; Hamada, Nobuyuki*

Radiation Protection Dosimetry, 183(1-2), p.247 - 250, 2019/05

 Times Cited Count:3 Percentile:20.8(Environmental Sciences)

As an application of Particle and Heavy Ion Transport code System PHITS, We have developed the stochastic microdosimetric kinetic (SMK) model for estimating the therapeutic effects of various kinds of radiation therapy. In this study, we improved the SMK model for estimating the therapeutic effect of boron neutron capture therapy, BNCT. The improved SMK model can consider not only the intra- and intercellular heterogeneity of B-10 distribution but also the dose rate effect. The accuracy of the model was well verified by comparisons made between calculated and measured surviving fractions of tumor cells, which we previously determined in vivo in mice with B-10 compounds exposed to reactor neutron beam. Details of the improved SMK model together with the verification results will be presented at the meeting.

Journal Articles

Development of novel alumina adsorbent applying mesoporous process

Fukumitsu, Nobuyoshi*; Yamauchi, Yusuke*; Saptiama, I.*; Ariga, Katsuhiko*; Hatano, Kentaro*; Kumada, Hiroaki*; Fujita, Yoshitaka; Tsuchiya, Kunihiko

Isotope News, (760), p.15 - 18, 2018/12

no abstracts in English

Journal Articles

Validation of the physical and RBE-weighted dose estimator based on PHITS coupled with a microdosimetric kinetic model for proton therapy

Takada, Kenta*; Sato, Tatsuhiko; Kumada, Hiroaki*; Koketsu, Junichi*; Takei, Hideyuki*; Sakurai, Hideyuki*; Sakae, Takeji*

Journal of Radiation Research, 59(1), p.91 - 99, 2018/01

 Times Cited Count:14 Percentile:9.11(Biology)

Evaluation of the relative biological effectiveness (RBE)-weighted dose is indispensable in the treatment planning of proton and carbon ion therapies. In this study, we validate the RBE-weighted dose calculated by microdosimetric kinetic model (MKM) in tandem with the Monte Carlo particle transport code PHITS for proton therapy using the full simulation geometry for the beam line of the Proton Medical Research Center at the University of Tsukuba. The physical dose and RBE-weighted dose on the central axis for a 155 MeV monoenergetic and spread-out Bragg peak beam of 60 mm width are evaluated by the method. The calculated results generally agree with the corresponding experimental data very well, though overestimations by approximately 3.2% and 15% at the maximum are observed for the physical and RBE-weighted doses, respectively. This research completes the computational microdosimetric approach based on a combination of PHITS and MKM for all types of radiotherapy that require RBE evaluations.

Journal Articles

Microdosimetric modeling of biological effectiveness for boron neutron capture therapy considering intra- and intercellular heterogeneity in $$^{10}$$B distribution

Sato, Tatsuhiko; Masunaga, Shinichiro*; Kumada, Hiroaki*; Hamada, Nobuyuki*

Scientific Reports (Internet), 8(1), p.988_1 - 988_14, 2018/01

 Times Cited Count:19 Percentile:5.56(Multidisciplinary Sciences)

We here propose a new model for estimating the biological effectiveness for boron neutron capture therapy (BNCT) considering intra- and intercellular heterogeneity in $$^{10}$$B distribution. The new model was developed from our previously established stochastic microdosimetric kinetic model that determines the surviving fraction of cells irradiated with any radiations, their synergetic effect being taken into account. The model can predict the biological effectiveness of newly developed $$^{10}$$B compounds based on their intra- and intercellular distributions, and thus, it can play important roles not only in treatment planning but also in drug discovery research for future BNCT.

Journal Articles

Beam commissioning of the linac for iBNCT

Naito, Fujio*; Anami, Shozo*; Ikegami, Kiyoshi*; Uota, Masahiko*; Ouchi, Toshikatsu*; Onishi, Takahiro*; Oba, Toshiyuki*; Obina, Takashi*; Kawamura, Masato*; Kumada, Hiroaki*; et al.

Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1244 - 1246, 2016/11

The proton linac installed in the Ibaraki Neutron Medical Research Center is used for production of the intense neutron flux for the Boron Neutron Capture Therapy (BNCT). The linac consists of the 3-MeV RFQ and the 8-MeV DTL. Design average beam current is 10mA. Target is made of Beryllium. First neutron production from the Beryllium target was observed at the end of 2015 with the low intensity beam as a demonstration. After the observation of neutron production, a lot of improvement s was carried out in order to increase the proton beam intensity for the real beam commissioning. The beam commissioning has been started on May 2016. The status of the commissioning is summarized in this report.

Journal Articles

Characteristics of radiation-resistant real-time neutron monitor for accelerator-based BNCT

Nakamura, Takemi; Sakasai, Kaoru; Nakashima, Hiroshi; Takamiya, Koichi*; Kumada, Hiroaki*

Journal of Radiation Protection and Research, 41(2), p.105 - 109, 2016/06

no abstracts in English

Journal Articles

Development of a proton accelerator for OIST BNCT

Kondo, Yasuhiro; Hasegawa, Kazuo; Higashi, Yasuo*; Kumada, Hiroaki*; Kurokawa, Shinichi*; Matsumoto, Hiroshi*; Naito, Fujio*; Yoshioka, Masakazu*

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.948 - 950, 2015/09

An accelerator based boron neutron capture therapy (BNCT) facility is being planned at Okinawa institute of science and technology (OIST). The proton accelerator consists of a radio frequency quadrupole (RFQ) linac and a drift tube linac (DTL). The reqired beam power is 60 kW. The present beam energy and current are 10 MeV and 30 mA, respectively. The pulse length is 3.3 ms and the repetition rate is 60 Hz, therefore, the duty factor is 20%. In this paper, present designof this compact, midium current, high duty proton linac is presented.

Journal Articles

Estimation of relative biological effectiveness for boron neutron capture therapy using the PHITS code coupled with a microdosimetric kinetic model

Horiguchi, Hironori*; Sato, Tatsuhiko; Kumada, Hiroaki*; Yamamoto, Tetsuya*; Sakae, Takeji*

Journal of Radiation Research, 56(2), p.382 - 390, 2015/03

 Times Cited Count:10 Percentile:46.02(Biology)

For evaluating the irradiation effect in tumors and surrounding normal tissues in BNCT, it is of great importance to estimate the relative biological effectiveness (RBE) for each dose component in the same framework. We have therefore established a new method for estimating the RBE of all BNCT dose components on the basis of the microdosimetric kinetic model. This method employs the probability densities of lineal energy, y, in a subcellular structure as the index for expressing RBE, which can be calculated using the microdosimetric function implemented in the particle transport simulation code PHITS. The accuracy of this method was tested by comparing the calculated RBE values with corresponding measured data in a water phantom irradiated with an epithermal neutron beam. The calculation technique developed in this study will be useful for biological dose estimation in the treatment planning of BNCT.

Journal Articles

Investigation of irradiation conditions for recurrent breast cancer in JRR-4

Horiguchi, Hironori; Nakamura, Takemi; Kumada, Hiroaki*; Yanagie, Hironobu*; Suzuki, Minoru*; Sagawa, Hisashi

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.234 - 237, 2010/10

Recurrent breast cancer has been considered the application for boron neutron capture therapy using the JRR-4. The investigation of irradiation conditions for the recurrent breast cancer was performed by simulation with the JCDS. We performed the preliminary dosimetry of the model to verify the efficient irradiation conditions such as the neutron energy modes and multiple field technique. From the result, when the 30 Gy-Eq dose as minimum dose was delivered to the cancers, comparable dose distribution was delivered at the healthy tissues by both a one-port irradiation from anterior direction and a two-port irradiation from tangential direction. We revealed that the two-port irradiation was not valid to reduce the healthy tissues dose due to the isotopic scattering of neutrons in the body. We concluded that the optimal irradiation condition was the one-port irradiation with thermal neutron beam mode in terms of less healthy tissues dose and shorter irradiation time.

Journal Articles

Resumption of JRR-4 and characteristics of the neutron beam for BNCT

Nakamura, Takemi; Horiguchi, Hironori; Kishi, Toshiaki; Motohashi, Jun; Sasajima, Fumio; Kumada, Hiroaki*

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.379 - 382, 2010/10

The clinical trials of BNCT have been conducted using JRR-4. The JRR-4 stopped in January 2008, because the graphite reflector was considerably damaged. For this reason, the specifications of graphite reflectors were renewal. All existing graphite reflectors of JRR-4 were changed by new graphite reflectors. The resumption of JRR-4 was carried out with new graphite reflectors in February 2010. We measured the characteristics of neutron beam at the JRR-4 Neutron Beam Facility. A cylindrical water phantom was put the gap for 1cm from the beam port. TLD and gold wire were inserted within the phantom when the phantom was irradiated. The results of the measured thermal neutron flux and the $$gamma$$ dose in water were compared with MCNP calculations. The calculated results showed the same tendency with the experimental results. These results are proceeding well and will be reported in full paper at July 2010.

Journal Articles

Multistep lattice-voxel method utilizing lattice function for Monte-Carlo treatment planning with pixel based voxel model

Kumada, Hiroaki*; Saito, Kimiaki; Nakamura, Takemi; Sakae, Takeji*; Sakurai, Hideyuki*; Matsumura, Akira*; Ono, Koji*

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.238 - 241, 2010/10

Journal Articles

Characteristics measurement of thermal neutron filter developed for improvement of therapeutic dose distribution of JRR-4

Kumada, Hiroaki*; Nakamura, Takemi; Horiguchi, Hironori; Matsumura, Akira*

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.414 - 417, 2010/10

Journal Articles

Feasible evaluation of neutron capture therapy for hepatocellular carcinoma using selective enhancement of boron accumulation in tumour with intra-arterial administration of boron-entrapped water-in-oil-in-water emulsion

Yanagie, Hironobu*; Kumada, Hiroaki*; Nakamura, Takemi; Higashi, Shushi*; Ikushima, Ichiro*; Morishita, Yasuyuki*; Shinohara, Atsuko*; Fujiwara, Mitsuteru*; Suzuki, Minoru*; Sakurai, Yoshinori*; et al.

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.157 - 160, 2010/10

JAEA Reports

Determination of boron concentration in whole blood by inductively coupled plasma atomic emission spectrometry for boron neutron capture therapy

Horiguchi, Hironori; Yamamoto, Kazuyoshi; Kishi, Toshiaki; Otake, Shinichi*; Kumada, Hiroaki*

JAEA-Research 2009-015, 38 Pages, 2009/07

JAEA-Research-2009-015.pdf:7.61MB

The boron neutron capture therapy (BNCT) has been conducted at JRR-4. There is an increased number of cases due to the expansion of application against head and neck cancer and skin cancer. Therefore, the BNCT requires the establishment of procedure to perform more cases in a day. The determination of boron concentration in blood is important to determine the prescribed dose given to a patient. Currently, prompt $$gamma$$ ray analysis (PGA) is applied to the determination of boron concentration. But the PGA is not applied to more than three times BNCT a day. Therefore, swiftness and precision method by inductively coupled plasma atomic emission spectrometry (ICP-AES) is studied. Using BSH for Boron standard of the ICP-AES, we enabled to analyze accurately without an intricate sample preparation. The measurement precision of the ICP-AES was within 5% by the correction factor based on the PGA. We established the method of swiftness determination of boron concentration in blood for BNCT.

Journal Articles

Performance measurement of the scintillator with optical fiber detector for boron neutron capture therapy

Komeda, Masao; Kumada, Hiroaki; Ishikawa, Masayori*; Nakamura, Takemi; Yamamoto, Kazuyoshi; Matsumura, Akira*

Applied Radiation and Isotopes, 67(7-8, Suppl.), p.S254 - S257, 2009/07

 Times Cited Count:3 Percentile:72.81(Chemistry, Inorganic & Nuclear)

Journal Articles

Data processing methods for dynamic neutron tomography velocimetry

Kureta, Masatoshi; Kumada, Hiroaki; Kume, Etsuo; Someya, Satoshi*; Okamoto, Koji*

Proceedings of 3rd International Workshop on Process Tomography (IWPT-3) (CD-ROM), 8 Pages, 2009/04

Dynamic neutron tomography velocimetry has been developed in order to obtain the 3-D velocity distribution and flow profile data of liquid metal flow in a heated rod bundle for development of an advanced nuclear reactor. In this paper, data processing methods for the 3-D velocimetry is focused on. The data processing is started from the reading images recorded by the three high-speed video cameras, and is finished to the visualization of velocity of the tracers and the profiles. Basic experiments were carried out using the research reactor JRR-4 and the dynamic neutron tomography system. As the results, it was confirmed that the 3-D velocity distribution and flow profile could be visualized by the new data processing methods.

Journal Articles

Dynamic neutron computer tomography technique for velocity measurement in liquid metal flow; Fundamental PTV experiment

Kureta, Masatoshi; Kumada, Hiroaki*; Kume, Etsuo; Someya, Satoshi*; Okamoto, Koji*

Journal of Physics; Conference Series, 147, p.012087_1 - 012087_14, 2009/03

The aim of this development is to visualize and measure the velocity distribution in liquid metal flow using the neutron beam with the high-speed imaging technique, computer tomography (CT) technique and particle tracking velocimetry (PTV). Final research purpose is to obtain the velocity distribution and flow profile data of liquid metal flow in a heated rod bundle for development of the FBR core. In this paper, visualization and measurement method using the JRR-4, spring model PTV method for this technique and results of the fundamental PTV experiment were reported. The fundamental experiment was conducted. As the result, cadmium tracers buried in the aluminum column with the speed of 1.5 revolving per second could be visualized as the 3D movie under 125Hz and 250Hz sampling conditions, the profile of the tracer could be traced, and fundamental velocity distribution measurement method could be conformed.

Journal Articles

Dynamic neutron computer tomography technique for velocity measurement in liquid metal flow; Fundamental PTV experiment

Kureta, Masatoshi; Kumada, Hiroaki; Kume, Etsuo; Someya, Satoshi*; Okamoto, Koji*

Proceedings of 6th International Symposium on Measurement Techniques for Multiphase Flows (ISMTMF 2008) (USB Flash Drive), 14 Pages, 2008/12

The aim of this development is to visualize and measure the velocity distribution in liquid metal flow using the neutron beam with the high-speed imaging technique, computer tomography (CT) technique and particle tracking velocimetry (PTV). Final research purpose is to obtain the velocity distribution and flow profile data of liquid metal flow in a heated rod bundle for development of the FBR core. In this paper, visualization and measurement method using the JRR-4, spring model PTV method for this technique and results of the fundamental PTV experiment were reported. The fundamental experiment was conducted. As the result, cadmium tracers buried in the aluminum column with the speed of 1.5 revolving per second could be visualized as the 3D movie under 125 Hz and 250 Hz sampling conditions, the profile of the tracer could be traced, and fundamental velocity distribution measurement method could be conformed.

128 (Records 1-20 displayed on this page)