Refine your search:     
Report No.
Search Results: Records 1-20 displayed on this page of 85

Presentation/Publication Type

Initialising ...


Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...


Initialising ...


Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Local structure study of the iron-based systems of BaFe$$_2$$As$$_2$$ and LiFeAs by X-ray PDF and XAFS analyses

Li, S.*; Toyoda, Masayuki*; Kobayashi, Yoshiaki*; Ito, Masayuki*; Ikeuchi, Kazuhiko*; Yoneda, Yasuhiro; Otani, Akira*; Matsumura, Daiju; Asano, Shun*; Mizuki, Junichiro*; et al.

Physica C, 555, p.45 - 53, 2018/12

 Times Cited Count:0 Percentile:100(Physics, Applied)

${it T}$-dependence of local distortions in BaFe$$_2$$As$$_2$$ and LiFeAs by X-ray PDF and XAFS methods. Although PDF data exhibit anomaly at the structure transition temperature, EXAFS data exhibit no anomaly. Data supporting the local orthorhombicity at 300 K in the tetragonal phase for BaFe$$_2$$As$$_2$$. Arguments on the origins of the 4-fold symmetry breaking in the ground average structure of the tetragonal phase.

Journal Articles

Nanoscale spatial analysis of clay minerals containing cesium by synchrotron radiation photoemission electron microscopy

Yoshigoe, Akitaka; Shiwaku, Hideaki; Kobayashi, Toru; Shimoyama, Iwao; Matsumura, Daiju; Tsuji, Takuya; Nishihata, Yasuo; Kogure, Toshihiro*; Okochi, Takuo*; Yasui, Akira*; et al.

Applied Physics Letters, 112(2), p.021603_1 - 021603_5, 2018/01

 Times Cited Count:2 Percentile:75.59(Physics, Applied)

A synchrotron radiation photoemission electron microscope (SR-PEEM) was applied to demonstrate pinpoint analysis of micrometer-sized weathered biotite clay particles with artificially adsorbed cesium (Cs) atoms. Despite the insulating properties of the clay, we observed the spatial distributions of constituent elements (Si, Al, Cs, Mg, Fe) without charging issues. We found that Cs atoms were likely to be adsorbed evenly over the entire particle. Spatially-resolved X-ray absorption spectra (XAS) of the Cs M$$_{4,5}$$-edge region showed Cs to be present in a monocation state (Cs$$^{+}$$). Further pinpoint XAS measurements were also performed at the Fe L$$_{2,3}$$-edge to determine the chemical valence of the Fe atoms. Our results demonstrate the utility of SR-PEEM as a tool for spatially-resolved chemical analyses of various environmental substances, which is not limited by the poor conductivity of samples.

Journal Articles

Innovation of hyper thermo therapy by laser and terahertz beam technology against cancer

Ishiyama, Shintaro; Miyoshi, Norio*; Idehara, Toshitaka*; Bibin, A.*; Kume, Kyo*; Matsumura, Akira*; Shtil, A. A.*

Hikari Araiansu, 23(12), p.19 - 23, 2012/12

To create new complete therapy for integrating various quantum beams, highly coalesed quantum beam science and technology are developing including neutron, X-ray, electron, synchrotron radiation and laser beams against cancer. This paper emphasizes the effectiveness of highly coalesced quantum beam science and technology in cancer, quoting case reports from promise in tests involving tumor model.

Journal Articles

The Analysis of boron micro-distribution in 9L gliosarmoma cells and HUVEC cells using PIXE and PIGE

Endo, Kiyoshi*; Shibata, Yasushi*; Yamamoto, Tetsuya*; Nakai, Kei*; Matsumura, Akira*; Sato, Takahiro; Yokoyama, Akihito; Koka, Masashi; Okubo, Takeru; Yamazaki, Akiyoshi; et al.

JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 86, 2012/01

Journal Articles

Single-shot observation of growing streamers using an ultrafast camera

Takahashi, Eiichi*; Kato, Susumu*; Furutani, Hirohide*; Sasaki, Akira; Kishimoto, Yasuaki*; Takada, Kenji*; Matsumura, Satoshi*; Sasaki, Hiroyasu*

Journal of Physics D; Applied Physics, 44(30), p.302001_1 - 302001_4, 2011/08

 Times Cited Count:7 Percentile:68.52(Physics, Applied)

A recently developed ultrafast camera that can acquire $$10^8$$ frames per second was used to investigate positive streamer discharge. It enabled single-shot evaluation of streamer evolution without the need to consider shot-to-shot reproducibility. This camera was used to investigate streamers in argon. Growing branches, the transition when a streamer forms a return stroke, and related phenomena were clearly observed.

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

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

Performance measurement of the SOF detector for boron neutron capture therapy

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

Proceedings of 13th International Congress on Neutron Capture Therapy (ICNCT-13) (CD-ROM), 3 Pages, 2008/11

In this report, deterioration of a SOF detector that can measure thermal neutron in real time was investigated in irradiation experiments. Sensitivity of a SOF detector decreased by 2.0% after an irradiation of about 4 hours. Then thermal neutron fluence was approximately 2.0$$times$$10$$^{13}$$ (n/cm$$^{2}$$). And after the SOF detector was used for about 2 months, sensitivity decreased to 42%. Then thermal neutron fluence was approximately 6.4$$times$$10$$^{14}$$ (n/cm$$^{2}$$). Supposing that thermal neutron fluence is 2$$times$$10$$^{12}$$ (n/cm$$^{2}$$) on the surface of a patient at a BNCT, sensitivity of a SOF detector is considered to be decreased by approximately 0.3% at a BNCT. Therefore it is considered that countermeasure against deterioration is necessary for using a SOF detector at BNCT in the future.

Journal Articles

Structural phase transition in the spin gap system YbAl$$_3$$C$$_3$$

Matsumura, Takeshi*; Inami, Toshiya; Kosaka, Masashi*; Kato, Yoshiaki*; Inukai, Takaki*; Ochiai, Akira*; Nakao, Hironori*; Murakami, Yoichi*; Katano, Susumu*; Suzuki, Hiroyuki*

Journal of the Physical Society of Japan, 77(10), p.103601_1 - 103601_4, 2008/10

 Times Cited Count:11 Percentile:39.82(Physics, Multidisciplinary)

Journal Articles

Development of JCDS, a computational dosimetry system at JAEA for boron neutron capture therapy

Kumada, Hiroaki; Yamamoto, Kazuyoshi; Matsumura, Akira*; Yamamoto, Tetsuya*; Nakagawa, Yoshinobu*

Journal of Physics; Conference Series, 74, p.021010_1 - 021010_7, 2007/00

no abstracts in English

Journal Articles

Failure patterns of high-grade glioma treated with BNCT

Matsuda, Masahide*; Yamamoto, Tetsuya*; Nakai, Kei*; Endo, Kiyoshi*; Kumada, Hiroaki; Kageji, Teruyoshi*; Matsumura, Akira*

Proceedings of 12th International Congress on Neutron Capture Therapy (ICNCT-12), p.40 - 42, 2006/10

To describe the failure patterns and survival seen with high-grade glioma treated with BNCT, the dose distribution and the clinical responses were retrospectively analyzed. BSH-based BNCT was performed in 12 patients with high-grade glioma (grade IV 7, grade III 5). The post-diagnosis median survival time of 12 patients was 19.8 months (range 3.3-47.2). Four cases of local control, 3 of local recurrence, 3 of distant intraparenchymal recurrence and 2 of subarachnoid dissemination were recorded. According to the analysis of the failure patterns, minimum GTV dose of 26 GyEq or more is necessary for local control.

Journal Articles

Development of a real-time thermal neutron monitor and its clinical application

Ishikawa, Masayori*; Ono, Koji*; Matsumura, Akira*; Yamamoto, Tetsuya*; Hiratsuka, Junichi*; Miyatake, Shinichi*; Kato, Itsuro*; Sakurai, Yoshinori*; Kobayashi, Toru*; Kumada, Hiroaki; et al.

Proceedings of 12th International Congress on Neutron Capture Therapy (ICNCT-12), p.397 - 400, 2006/10

An ultraminiature thermal neutron monitor which was named SOF detector (Scintillator with Optical Fiber detector) had been developed for BNCT treatment. We had been experienced 15 clinical trials using SOF detector until the end of 2005, some measurements got good results, and some got unacceptable results. One reason of the unacceptable results was due to dislocation of the detector during treatment. This is because it is difficult to fix the SOF detector on patient's skin without strong sticker. To overcome this problem, a loop-type SOF probe was developed. By using the loop-type SOF detector, fixing on the patient's skin was much easier.

Journal Articles

A Migration analysis of ${it Sogatella furcifera}$ (Horv$'a$th) (Homoptera: Delphacidae) using hourly catches and a three-dimensional simulation model

Otsuka, Akira*; Watanabe, Tomonari*; Suzuki, Yoshito*; Matsumura, Masaya*; Furuno, Akiko; Chino, Masamichi; Kondo, Tomoya*; Kamimuro, Tsuyoshi*

Agricultural and Forest Entomology, 8(1), p.35 - 47, 2006/02

 Times Cited Count:16 Percentile:37.73(Entomology)

1 Migration of Sogatella furcifera captured in Japan in the 2003 season were analyzed using hourly catches and a simulation model.2. The catch data showed several clear migration peaks, with average durations of 4 h. The peaks were separated from each other by approximately 12 h, corresponding to the observed fact that planthoppers take off at dusk and dawn.3. The simulation model, together with the hourly catches, enabled an estimation of migration source regions.4. Possible migration sources during our hourly observation period were located in the coastal area of Fujian province in China, as well as Taiwan.

Journal Articles

Development of a numerical simulation model for long-range migration of rice planthoppers

Furuno, Akiko; Chino, Masamichi; Otsuka, Akira*; Watanabe, Tomonari*; Matsumura, Masaya*; Suzuki, Yoshito*

Agricultural and Forest Meteorology, 133(1-4), p.197 - 209, 2005/11

 Times Cited Count:13 Percentile:52.76(Agronomy)

Transoceanic migration of rice planthoppers was precisely simulated by incorporating several parameters related to the flight behavior with a high performance atmospheric dispersion model. The model consists of an atmospheric dynamic submodel and a particle random-walk submodel for atmospheric dispersion. The model also functions in specifying the release area of the migration of planthoppers. Using this model, we carried out a case study simulating the migration of planthoppers to western Japan in mid-June 1998. In the simulation, 56 areas each with a width of two degrees of latitude and longitude were set as tentative take-off areas. The calculated density of immigrants was compared with each observed density by rank correlation coefficients. Possible migration release areas which showed a high correlation to observations were distributed around 23-27N, including Fujian and Taiwan. An air temperature that allowed the planthoppers to fly continuously and flight duration were critical parameters for the simulation results.

Journal Articles

Development of computational dosimetry system "JCDS" for neutron capture therapy

Kumada, Hiroaki; Yamamoto, Kazuyoshi; Matsumura, Akira*; Nakagawa, Yoshinobu*

Hoshasen, 31(4), p.287 - 297, 2005/10

no abstracts in English

JAEA Reports

Estimation methods of blood boron concentration and error evaluation during boron neutron capture therapy for malignant brain tumor

Shibata, Yasushi*; Yamamoto, Kazuyoshi; Matsumura, Akira*; Yamamoto, Tetsuya*; Hori, Naohiko; Kishi, Toshiaki; Kumada, Hiroaki; Akutsu, Hiroyoshi*; Yasuda, Susumu*; Nakai, Kei*; et al.

JAERI-Research 2005-009, 41 Pages, 2005/03


The measurement of neutron flux and boron concentration in the blood during medical irradiation is indispensable in order to evaluate the radiation in boron neutron capture therapy. It is, however, difficult to measure the blood boron concentration during neutron irradiation because access to the patient is limited. Therefore we prospectively investigated the predictability of blood boron concentrations using the data obtained at the first craniotomy after infusion of a low dosage of BSH. When the test could not be carried out, the blood boron concentration during irradiation was also predicted by using the 2-compartment model. If the final boron concentration after the end of the infusion is within 95% confidence interval of the prediction, direct prediction from biexponential fit will reduce the error of blood boron concentrations during irradiation to around 6%. If the final boron concentration at 6 or 9 hours after the end of infusion is out of 95% confidence interval of the prediction, proportional adjustment will reduce error and expected error after adjustment to around 12%.

Journal Articles

Combination of boron and gadolinium compounds for neutron capture therapy; An $$in Vitro$$ study

Matsumura, Akira*; Zhang, T.*; Nakai, Kei*; Endo, Kiyoshi*; Kumada, Hiroaki; Yamamoto, Tetsuya*; Yoshida, Fumiyo*; Sakurai, Yoshinori*; Yamamoto, Kazuyoshi; Nose, Tadao*

Journal of Experimental and Clinical Cancer Research, 24(1), p.93 - 98, 2005/03

no abstracts in English

Journal Articles

Development of the JAERI Computational Dosimetry System (JCDS) for boron neutron capture therapy

Kumada, Hiroaki; Yamamoto, Kazuyoshi; Murayama, Yoji; Matsumura, Akira*; Nakagawa, Yoshinobu*

Monte Karuro Keisanho Kodoka No Genjo; Dai-3-Kai Monte Karuro Shimyureshon Kenkyukai Hobunshu, p.185 - 194, 2004/12

no abstracts in English

Journal Articles

Improvement of dose calculation accuracy for BNCT dosimetry by the multi-voxel method in JCDS

Kumada, Hiroaki; Yamamoto, Kazuyoshi; Yamamoto, Tetsuya*; Nakai, Kei*; Nakagawa, Yoshinobu*; Kageji, Teruyoshi*; Matsumura, Akira*

Applied Radiation and Isotopes, 61(5), p.1045 - 1050, 2004/11

 Times Cited Count:9 Percentile:44.08(Chemistry, Inorganic & Nuclear)

To carry out the BNCT clinical trials based on accurate dosimetry of several absorbed doses given to a patient, we have developed JCDS which can determine the absorbed doses by numerical simulation. The aim of this study is to improve the accuracy of the BNCT dosimetry efficiently. We have developed the multi-voxel calculation method reconstructing the original voxel model by combining of several voxel cell sizes such as in 5mm, 10mm and 20mm voxel cell. To verify the accuracy of the multi-voxel method, the calculation results were compared with the phantom experimental data. These results proved that the multi-voxel calculation enables JCDS to more accurately estimate the absorbed doses to a patient by efficient calculations.

85 (Records 1-20 displayed on this page)