Crystallization and preliminary neutron diffraction studies of ADP-ribose pyrophosphatase-I from HB8

Okazaki, Nobuo; Adachi, Motoyasu; Tamada, Taro; Kurihara, Kazuo; Oga, Takushi*; Kamiya, Nobuo*; Kuramitsu, Seiki*; Kuroki, Ryota

Acta Crystallographica Section F, 68(1), p.49 - 52, 2012/01

https://doi.org/10.1107/S1744309111044551

Development of head module for multi-head Si/CdTe Compton camera for medical applications

Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.

Nuclear Instruments and Methods in Physics Research A, 648(Suppl.1), p.S2 - S7, 2011/08

https://doi.org/10.1016/j.nima.2011.02.040

We are constructing a three-dimensional imaging system for medical and biological applications. The system will allow simultaneous imaging at high spatial and energy resolutions across a wide energy range, from several tens of keV to a few MeV. In this work, one prototype head module have been developed for a multi-head Si/CdTe Compton camera system. The performance of the prototype was evaluated with a sealed Ba-133 radiation source. The experiments confirmed that the imaging results were consistent with actual source position. In addition to the resolution for the parallel directions to the detector surface, the position resolution was evaluated for the depth direction at a point in near region of the head-module. These position resolutions were well reproduced by Monte Carlo simulation results.

Partial crystallization of silicon by high intensity laser irradiation

Azuma, Hirozumi*; Sagisaka, Akito; Daido, Hiroyuki; Ito, Isao*; Kadoura, Hiroaki*; Kamiya, Nobuo*; Ito, Tadashi*; Nishimura, Akihiko; Ma, J.*; Mori, Michiaki; et al.

Applied Surface Science, 255(24), p.9783 - 9786, 2009/09

https://doi.org/10.1016/j.apsusc.2009.04.143

Commercial single crystal silicon wafers and amorphous silicon films piled on single crystal silicon wafers were irradiated with a femtosecond pulsed laser and a nanosecond pulsed laser at irradiation intensities between 10 W/cm and 10 W/cm. In the single crystal silicon substrate, the irradiated area was changed to polycrystalline silicon and the piled silicon around the irradiated area has spindly column structures constructed of polycrystalline and amorphous silicon. In particular, in the case of the higher irradiation intensity of 10 W/cm, the irradiated area was oriented to the same crystal direction as the substrate. In the case of the lower irradiation intensity of 10 W/cm, only amorphous silicon was observed around the irradiated area, even when the target was single crystal silicon.

Precision determination of charge dispersion and distribution in the proton-induced fission of U at 13.9MeV excitation

Yokoyama, Akihiko*; *; *; *; *; *; *; Takamiya, Koichi*; Shinohara, Nobuo; Tsukada, Kazuaki; et al.

Z. Phys., A, 356(1), p.55 - 60, 1996/00

no abstracts in English

Development of Si/CdTe Compton camera for medical imaging

Yamaguchi, Mitsutaka; Kamiya, Tomihiro; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Ishioka, Noriko; Watanabe, Shin*; Ishikawa, Shinnosuke*; Odaka, Hirokazu*; Kokubun, Motohide*; et al.

no journal, , 

We have developed a prototype of Si/CdTe medical Compton camera. To overcome low spatial resolution of one head camera, we have proposed multi-head Compton camera. In this work, we studied the spatial resolution by comparing the measured resolution with Monte Carlo simulation. The head of the Compton camera consist of two layers of Si strip detector and two layers of CdTe strip detector. Monte Carlo simulations were performed by using a camera simulator Geant4 toolkit. After the Monte Carlo simulations, imaging process using LM-ML-EM, algorithm was performed in a 3D-space. The measured result was well agree with the simulation result. The spatial resolution is about 6 mm for double-head case while the spatial resolution of depth direction is about 15 mm for single-head case. These results indicate that the spatial resolution is improved and clear 3D-image is taken by using multi-head Compton camera.

Development of a head module for multi-head Si/CdTe Compton camera

Yamaguchi, Mitsutaka; Kamiya, Tomihiro; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.

no journal, , 

We are constructing a three-dimensional imaging system for medical and biological applications as a device that can provide simultaneous imaging, having high spatial and energy resolutions and wide energy range from several tens keV to a few MeV, by diverting the most advanced space-observation technology, Si/CdTe semiconductor Compton camera, developed in ISAS/JAXA. The Si/CdTe Compton camera was developed under the assumption that the use of moderate temperature and the Analog ASIC for signal processing. Moreover, because the solid and thin scattering layer allows close placement of the measured object, good angular resolution corresponds to good spatial resolution directly. These aspects allow construction of compact medical system. In contrast to space-observation use, three-dimensional imaging ability becomes important for life science research. In order to achieve a good three-dimensional spatial resolution, modularizing the Compton camera into a small camera head and allowing multi-angle imaging with multi-head structure is required. In this work, a head module has been developed as a prototype module of the multi-head system. Sensor and circuit modules are closely arranged and put in a compact vacuum-insulating cylindrical housing. Each of camera heads will be fixed on robot arms and be able to adjust the positions and the directions. Performance evaluation test was made for the prototype module with a sealed Ba-133 radiation source. We confirmed that the imaging result is consistent with the source positioning. The angular resolution measure, abbreviated as ARM, was estimated to be 4.5 degree. The result of the test was compared with a Monte Carlo simulation study. We will report the details of the prototype module and the result of the performance evaluation test. The expecting three-dimensional performance will also be reported.

Development of a Si/CdTe Compton camera for medical and biological application

Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.

no journal, , 

no abstracts in English

Substantiative experiments of distortion correction for novel Si/CdTe Compton camera

Kawachi, Naoki; Yamaguchi, Mitsutaka; Nagao, Yuto; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Kokubun, Motohide*; Takeda, Shinichiro*; Ishikawa, Shinnosuke*; et al.

no journal, , 

Neutron crystal structure of ADP-ribose pyrophosphatase-I from Thermus thermophilus HB8

Okazaki, Nobuo; Adachi, Motoyasu; Ohara, Takashi; Tamada, Taro; Kurihara, Kazuo; Oga, Takushi*; Kamiya, Nobuo*; Kuramitsu, Seiki*; Kuroki, Ryota

no journal, , 

no abstracts in English

Characterization of rice transporter OsLCT1 responsible for cadmium transport into grains

Uraguchi, Shimpei*; Suzui, Nobuo; Kamiya, Takehiro*; Yin, Y.-G.; Ishii, Satomi; Fujimaki, Shu; Fujiwara, Toru*

no journal, ,