Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Matsuo, Tatsuhito; Natali, F.*; Plazanet, M.*; Zaccai, G.*; Fujiwara, Satoru
Journal of the Physical Society of Japan, 82(Suppl.A), p.SA020_1 - SA020_5, 2013/01
Times Cited Count:3 Percentile:27.66(Physics, Multidisciplinary)Troponin is a protein that regulates the muscle contraction depending on the intracellular Ca concentration. K247R mutation of TnT is known to cause the hypertrophic cardiomyopathy. In this work, neutron scattering was used to detect possible changes in dynamics of troponin caused by mutation. Elastic incoherent neutron scattering experiments were carried out on solution samples of the wild type, and K247R mutant at the IN13 spectrometer at the Institut Laue-Langevin, at temperatures between 280 K and 292 K with an interval of 3 K. From the measured scattering data, force constants (
k
), which reflect the resilience of the protein, were calculated. The
k
values for the wild type and K247R mutant were 0.077 (0.035) N/m and 0.046 (0.026) N/m (mean(s.d.)), respectively. This suggests that the disease-causing mutant is more flexible than the wild type. The large flexibility might modulate Ca
signal transmission mechanism, leading to the functional aberration.
Arai, Masatoshi; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Nakajima, Kenji; Shibata, Kaoru; Takahashi, Nobuaki; Suzuki, Junichi*; Takata, Shinichi; Yamada, Takeshi*; et al.
Journal of the Physical Society of Japan, 82(Suppl.A), p.SA024_1 - SA024_14, 2013/01
Times Cited Count:7 Percentile:48(Physics, Multidisciplinary)The paper describes developments of neutron scattering instruments in J-PARC neutron facility, which is a short pulse spallation source operated at a repetition rate 25 Hz and has a proton power 1 MW. New concept has been adopted to utilize high intensity coupled moderator even for a high resolution inelastic scattering instruments by taking a pulse shaping chopper system. Advanced technique has been also realized by taking an ability of event-recording system altogether with an improvement of a chopper system, realizing multi-Ei method. The paper also touches upon a general design concept for diffractometers in accordance with the source characteristics.
Ikeuchi, Kazuhiko*; Nakamura, Mitsutaka; Kajimoto, Ryoichi; Arai, Masatoshi
Journal of the Physical Society of Japan, 82(Suppl.A), p.SA038_1 - SA038_5, 2013/01
Times Cited Count:5 Percentile:39.6(Physics, Multidisciplinary)Wakimoto, Shuichi; Harayama, Sayaka; Kakurai, Kazuhisa; Kawakami, Jun; Matsubayashi, Masahito; Matsue, Hideaki; Takahashi, Hiroyuki; Utsumi, Wataru
no journal, ,
Wakimoto, Shuichi; Kaneko, Koji; Kubota, Masato; Osakabe, Toyotaka; Shimojo, Yutaka; Takeda, Masayasu; Yamauchi, Hiroki
no journal, ,
Kakurai, Kazuhisa; Wakimoto, Shuichi; Kaneko, Koji; Takeda, Masayasu; Nakamura, Mitsutaka; Nakajima, Kenji; Nishi, Masakazu*; Endo, Yasuo
no journal, ,
Nakamura, Mitsutaka; Kambara, Wataru; Krist, T.*; Shinohara, Takenao; Ikeuchi, Kazuhiko*; Arai, Masatoshi; Kajimoto, Ryoichi*; Nakajima, Kenji; Tanaka, Hiromichi; Suzuki, Junichi*; et al.
no journal, ,
In order to improve the measurement efficiency of inelastic neutron scattering experiment, we developed a new Fermi chopper with a supermirror-coated slitpackage (MAGIC chopper). In this study, we report the experimental demonstration that the full optimization of the experimental condition for multiple incident energies is nearly achieved by the prototype of MAGIC chopper.
Nakajima, Kenji
no journal, ,
In this presentation, we will overview the issues related to RRM based techniques used at our inelastic instruments at MLF, whose details will be presented in separate papers in this workshop.
Fujiwara, Satoru; Plazanet, M.*; Oda, Toshiro*
no journal, ,
Fujiwara, Satoru; Yamada, Takeshi*; Matsuo, Tatsuhito; Takahashi, Nobuaki; Kamazawa, Kazuya*; Kawakita, Yukinobu; Shibata, Kaoru*
no journal, ,
Kikuchi, Tatsuya; Nakajima, Kenji; Kawamura, Seiko; Inamura, Yasuhiro; Yamamuro, Osamu*; Kofu, Maiko*; Kawakita, Yukinobu; Suzuya, Kentaro; Nakamura, Mitsutaka; Arai, Masatoshi
no journal, ,
In generally so far, analysis of quasi-elastic neutron scattering spectra needs some mathematical models in its process, and hence the obtained result is a model dependent. In this context, we are trying to develop new model-free analysis method which we call as mode distribution analysis. In this method, we supposed that all modes can be described as combinations of the relaxations based on the exponential law. In the result of the analysis, we can obtain an intensity distribution for HWHM of Loretzian. This function can show the number of modes and distributions of the relaxation times in the modes and we call it as mode distribution function (MDF). In this new approach, we can obtain the MDF by using the maximum entropy method (MEM). We will also report a first application of our method to HO at RT. The measurement was carried out on AMATERAS spectrometer installed at J-PARC. In the result, we discover a motion of water molecule, which has not reported by earlier studies.
Inamura, Yasuhiro; Nakatani, Takeshi; Kajimoto, Ryoichi*; Suzuki, Jiro*; Otomo, Toshiya*
no journal, ,
Our software, named "Utsusemi", has already been utilized in actual users measurements, while we are proceeding with developments for more effective use of high flux neutrons and event-recording methods. Especially, we have successfully demonstrated a measurement of a single crystal of 3D spin system; several tens of measurements by rotating the sample, and visualization of the measured data forming intensity maps in large Q space. This has been achieved by developments of software to perform automatic devices control (sample rotation and data acquisition) and to handle huge data for visualization. Also, we approach developments for the system to make and use event-recorded data from instruments information and sample environments, for example a chopper phasing, temperature and direction of a sample. These event data also can be stored by same DAQ software as neutrons and used in analysis to filter neutrons events by conditions of both an instrument and samples.
Endo, Hitoshi; Takano, Atsushi*
no journal, ,
The dynamic structure factor of random copolymer was investigated by neutron spin echo technique. The theoretical dynamic structure for random copolymer was derived theoretically, which was deviated from that of homo polymer. Our experimental results supported this theoretical prediction. Furthermore, it became apparent that the theory based on Gaussian approximation violated gradually from large to small space.