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Nagae, Daisuke*; Abe, Yasushi*; Okada, Shunsuke*; Omika, Shuichiro*; Wakayama, Kiyoshi*; Hosoi, Shun*; Suzuki, Shinji*; Moriguchi, Tetsuro*; Amano, Masamichi*; Kamioka, Daiki*; et al.
Nuclear Instruments and Methods in Physics Research A, 986, p.164713_1 - 164713_7, 2021/01
Times Cited Count:5 Percentile:65.59(Instruments & Instrumentation)Yonezawa, Yasushi*; Nagayama, Aiko*; Tokunaga, Hiroko*; Ishibashi, Matsujiro*; Arai, Shigeki; Kuroki, Ryota; Watanabe, Keiichi*; Arakawa, Tsutomu*; Tokunaga, Masao*
Protein Journal, 34(4), p.275 - 283, 2015/08
Times Cited Count:4 Percentile:11.12(Biochemistry & Molecular Biology)Nucleoside diphosphate kinase isolated from psychrophilic sp. AS-131 (ASNDK) was expressed in and purified to homogeneity. Comparing to mesophilic NDK isolated from , ASNDK exhibited highly elevated thermolability: (1) expression at 37C as a denatured insoluble form, and (2) 30C lower optimum temperature of enzymatic activity. The subunit structure of ASNDK was suggested to be dimer, as in NDKs isolated from moderate halophiles.
Eto, Haruhiko*; Aoki, Yasushi*; Mitsubori, Hitoshi*; Arakawa, Y.*; Mitsumoto, Toshinori*; Yajima, S.*; Sakuraba, Junji*; Kato, Takanori*; Okumura, Yoshikazu
Review of Scientific Instruments, 85(2), p.02B107_1 - 02B107_3, 2014/02
Times Cited Count:10 Percentile:42.95(Instruments & Instrumentation)High current hydrogen negative ion source is required to increase the accelerated beam current of the cyclotrons for many medical applications such as cancer therapy and medical radioisotope production. A new negative ion source has been designed and fabricated. The ion source is a multi-cusp type. Optimization of the ion source is in progress, such as the optimization of the magnetic filter which prevents high temperature electrons from entering into the negative ion production region, improvement of the extraction electrode's shape and configuration of dipole magnets etc. A small quantity of Cs has been introduced into the ion source to enhance the negative ion beam current. The ion source produced 16mA of DC hydrogen negative ion beam with the Cs-seeded operation at a low arc discharge power of 2.8 kW.
Tokunaga, Hiroko*; Izutsu, Kenichi*; Arai, Shigeki; Yonezawa, Yasushi; Kuroki, Ryota; Arakawa, Tsutomu*; Tokunaga, Masao*
Enzyme and Microbial Technology, 46(2), p.129 - 135, 2010/02
Times Cited Count:6 Percentile:20.75(Biotechnology & Applied Microbiology)Both wild-type nucleoside diphosphate kinase from moderately halophilc (CsNDK (GNE), GNE represents Gly134-Asn135-Glu136) and mutant CsNDK (ANE), both of which have a neutral amino acid at residue 134, were found to form a dimer. These constructs contain Glu136, which may also cause steric barrier and charge repulsion. A double mutant, CsNDK (ANT), having Thr at 136 resulted in stable tetrameric assembly, supporting the above notion. A mutant CsNDK (GNT) reverted, however, to a dimer again, indicating that the introduced Ala residue at 134th in the double mutant generated a hydrophobic cluster consisting of the Ala residues and thereby stabilized dimer-dimer association of CsNDK assembly, while Gly destabilized it due to the loss of this cluster. Based on these observations, it is evident that both residues 134 and 136 contribute to the subunit assembly of CsNDK.
Arakawa, Kazuo; Oikawa, Masakazu*; Shimada, Hirofumi*; Kamiya, Tomihiro; Nakano, Takashi*; Yusa, Ken*; Kato, Hiroyuki*; Sato, Takahiro; Agematsu, Takashi; Kashiwagi, Hirotsugu; et al.
Proceedings of 4th Annual Meeting of Particle Accelerator Society of Japan and 32nd Linear Accelerator Meeting in Japan (CD-ROM), p.279 - 281, 2007/00
no abstracts in English
Endo, Kiyoshi*; Shibata, Yasushi*; Yoshida, Fumiyo*; Nakai, Kei*; Yamamoto, Tetsuya*; Matsumura, Akira*; Ishii, Keizo*; Sakai, Takuro; Sato, Takahiro; Oikawa, Masakazu*; et al.
Proceedings of 11th World Congress on Neutron Capture Therapy (ISNCT-11) (CD-ROM), 2 Pages, 2004/10
Micro PIXE, which is installed in a single end accelerator in JAERI, was used for quantitative analysis of boron and gadolinium distribution in a cell level. The micro beam of 1 m diameter is possible to observe the distribution. In the adjustment procedure of the sample, first is a fix of mylar film by using a glass ring and a bite ring of 2cm diameter. Next the 9L cells were scattered on the washed film, and is cultivated on 37C in medium until they form the mono-layer. After the Gd-BOPTA was added, it incubates for the 24-72 hour on 37C. The film is washed in the THAM liquid, and is directly put on liquid nitrogen. A vacuum drying for 24 hours is conducted in order to fix a film on holder. It is important to uniformly fix the cell in distribution analysis in the cell using Micro PIXE. In recent result, it became possible that the distribution of P, S, Gd, etc. was analyzed. But we could not distinguish whether K and Gd exist in the cell or whether it exists around the cell. It was indicated that these elements was leaked by the reason of cell breaking or other on the cytoplasm.
Fukuda, Mitsuhiro; Kurashima, Satoshi; Miyawaki, Nobumasa; Okumura, Susumu; Kamiya, Tomihiro; Oikawa, Masakazu*; Nakamura, Yoshiteru; Nara, Takayuki; Agematsu, Takashi; Ishibori, Ikuo; et al.
Nuclear Instruments and Methods in Physics Research B, 210, p.33 - 36, 2003/09
Times Cited Count:4 Percentile:33.69(Instruments & Instrumentation)A heavy ion microbeam with energy of hundreds MeV is a significantly useful probe for research in biotechnology. A single-ion hitting technique using a 260 MeV Ne microbeam is being developed at the JAERI AVF cyclotron facility for biofunction elucidation. Production of a microbeam with a spot size of one micro-meter in diameter requires reducing the energy spread of the beam to 0.02 % to minimize an effect of chromatic aberrations in focusing lenses. The typical energy spread of the cyclotron beam is around 0.1 % in an ordinary acceleration mode using a sinusoidal voltage waveform. The energy spread can be reduced by superimposing the fifth-harmonic voltage waveform on the fundamental one to generate a flattop waveform for uniform energy gain. We have designed an additional coaxial cavity to generate the fifth-harmonic voltage, coupled to the main resonator of one-fourth wavelength coaxial type. In a power test we successfully observed the fifth-harmonic voltage waveform by picking up an acceleration voltage signal.
Fukuda, Mitsuhiro; Kurashima, Satoshi; Okumura, Susumu; Miyawaki, Nobumasa; Agematsu, Takashi; Nakamura, Yoshiteru; Nara, Takayuki; Ishibori, Ikuo; Yoshida, Kenichi; Yokota, Wataru; et al.
Review of Scientific Instruments, 74(4), p.2293 - 2299, 2003/04
Times Cited Count:14 Percentile:58.66(Instruments & Instrumentation)A combination of the fundamental- and the fifth-harmonic voltages is ideally suited for flat-top acceleration in a variable-energy multi-particle cyclotron for energy-spread minimization. The flat-topping of the energy gain distribution using the fifth-harmonics has the advantages of minimizing an amplifier power, reducing power dissipation in a resonator and increasing the energy gain per turn. The flat-top acceleration system of the JAERI AVF cyclotron was designed to reduce the energy spread to 0.02 , required for microbeam production. Tolerable fluctuations of acceleration voltages and the magnetic excitation were 2.010 for the fundamental voltage, 1.010 for the fifth-harmonic voltage, and 1.910 for the magnetic field. In order to enhance compactness of the flat-topping cavity and to make a substantial saving of the amplifier power, optimum geometric parameters of the flat-topping cavity were determined by a cold model test and a calculation using the MAFIA code.
Kurashima, Satoshi; Fukuda, Mitsuhiro; Nakamura, Yoshiteru; Nara, Takayuki; Agematsu, Takashi; Ishibori, Ikuo; Tamura, Hiroyuki; Yokota, Wataru; Okumura, Susumu; Arakawa, Kazuo; et al.
AIP Conference Proceedings 600, p.303 - 305, 2001/00
A flat-top acceleration system for the JAERI AVF cyclotron has been designed. The fifth harmonic of the fundamental frequency is used to obtain uniform energy gain. To determine optimum parameters of the flat-top system, a cold model test was carried out and flat-top waveforms of the voltages were observed successfully in the whole range of the fundamental frequency. An rf power required for generating a flat-top dee voltage of 30 kV was estimated to be about 1 kW. The design of the flat-top cavity is being modified using the MAFIA code.
Takeda, Toshikazu*; Unesaki, Hironobu*; Nakano, Makoto*; Arakawa, Yasushi*; Sakuma, Hiroomi*; Kurisaka, Kenichi*; Ito, Noboru*; Oe, Takashi*; Yamaguchi, Yoshiharu*
PNC TJ2605 87-001, 204 Pages, 1987/03
no abstracts in English
Takeda, Toshikazu*; Kamide, Hideki*; Unesaki, Hironobu*; Nishigori, Takeo*; Sasaki, Yoshiaki*; Tsujimoto, Keiichi*; Arakawa, Yasushi*; Umano, Takuya*; Suzuki, Takayuki*
PNC TJ265 85-01, 197 Pages, 1985/03
no abstracts in English
Fukuda, Mitsuhiro; Arakawa, Kazuo; Sato, Takahiro; Okumura, Susumu; Saito, Yuichi; Kashiwagi, Hirotsugu; Miyawaki, Nobumasa; Yuri, Yosuke; Ishii, Yasuyuki; Kobayashi, Yasuhiko; et al.
no journal, ,
no abstracts in English
Arakawa, Kazuo; Fukuda, Mitsuhiro*; Shimada, Hirofumi*; Sakai, Takuro; Sato, Takahiro; Oikawa, Masakazu*; Agematsu, Takashi; Kashiwagi, Hirotsugu; Okumura, Susumu; Kurashima, Satoshi; et al.
no journal, ,
no abstracts in English
Shimada, Hirofumi*; Oikawa, Masakazu*; Sato, Takahiro; Taguchi, Mitsumasa; Okumura, Susumu; Kato, Hiroyuki*; Yusa, Ken*; Sakai, Takuro; Fukuda, Mitsuhiro*; Sato, Taku*; et al.
no journal, ,
no abstracts in English