Photosystem I and II Reaction Centers in a New Type Oxygenic Photosynthesis of Acaryochloris marina Based on Chlorophyll d: Studies of Delayed Fluorescence and Triplet State ESR

Itoh, Shigeru,Fukushima, Yoshimasa,Itoh, Kunihiro,Maeda, Masanori,Mino, Hiroyuki,Kumazaki, Shigeichi Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

A cyanobacteria-like organism Aaryochloris marina performs oxygenic photosynthesis with near far-red light by the use of chlorophyll d. Reaction center chlorophyll (Chl) of Photosystem (PS) II of A. marina was studied by analysis of millisecond-delayed fluorescence. Delayed fluorescence is emitted by Chi d indicating efficient energy transfer between antenna Chi d molecules and the unknown primary electron donor of PS II. P740 a reaction center Chl of PS I of A. marina is shown to give a dimer type cation, and triplet state with a D value of 245xlO$\^$-4/ cm$\^$-l/ in contrast to the 280-290 xlO$\^$-4/cm$\^$-l/ values of P700 suggesting triplet spins interacting at a 5% larger distance in P740 than in P700.

Hysteresis and fast timescales in transport relations of toroidal plasmas

Itoh, K.,Itoh, S.-I.,Ida, K.,Inagaki, S.,Kamada, Y.,Kamiya, K.,Dong, J.Q.,Hidalgo, C.,Evans, T.,Ko, W.H.,Park, H.,Tokuzawa, T.,Kubo, S.,Kobayashi, T.,Kosuga, Y.,Sasaki, M.,Yun, G.S.,Song, S.D.,Kasuya, International Atomic Energy Agency 2017 Nuclear fusion Vol.57 No.10

<P>This article assesses current understanding of hysteresis in transport relations, and its impact on the field. The rapid changes of fluxes compared to slow changes of plasma parameters are overviewed for both core and edge plasmas. The modulation ECH experiment is explained, in which the heating power cycles on-and-off periodically, revealing hysteresis and fast changes in the gradient–flux relation. The key finding is that hystereses were observed simultaneously in both the the gradient–flux and gradient–fluctuation relations. Hysteresis with rapid timescale exists in the channels of energy, electron and impurity densities, and plausibly in momentum. Advanced methods of data analysis are explained. Transport hysteresis can be studied by observing the higher harmonics of temperature perturbation <img ALIGN='MIDDLE' ALT='$\delta T_{\rm m}$ ' SRC='http://ej.iop.org/images/0029-5515/57/10/102021/nfaa796aieqn001.gif'/> in heating modulation experiments. The hysteresis introduces the term <img ALIGN='MIDDLE' ALT='$\delta T_{\rm m}$ ' SRC='http://ej.iop.org/images/0029-5515/57/10/102021/nfaa796aieqn002.gif'/>, which depends on the harmonic number <I>m</I> in an algebraic manner (not exponential decay). Next, the causes of hysteresis and its fast timescale are discussed. The nonlocal-in-space coupling works here, but does not suffice. One mechanism for ‘the heating heats turbulence’ is that the external source <I>S</I> in phase space for heating has its fluctuation in turbulent plasma. This coupling can induce the direct input of heating power into fluctuations. The height of the jump in transport hysteresis is smaller for heavier hydrogen isotopes, and could be one of the origins of isotope effects on confinement. Finally, the impacts of transport hysteresis on the control system are assessed. Control systems must be designed so as to protect the system from sudden plasma loss.</P>

Electroretinography recordings using a light emitting diode active corneal electrode in healthy beagle dogs

Yoshiki Itoh,Yasuharu Izumisawa,Seiya Maehara,Kazuto Yamashita,Norihiko Itoh 대한수의학회 2013 JOURNAL OF VETERINARY SCIENCE Vol.14 No.1

Electroretinography (ERG) is a well-established diagnostic procedure for objectively evaluating retinal function. In this study, ERG in beagle dogs, which are a popular experimental animal, was performed to determine the normal range of ERG variables and assess differences between the left and right eyes. ERG findings including rod, combined rod-cone,single-flash cone, and 30-Hz flicker responses were recorded with an LED-electrode in 43 sedated beagle dogs. The subjects were divided into young (< 1 year old), adult (1∼5years old), and senile animals (≥ 6 years old). Normal ERG ranges were obtained. Significant differences in b-wave amplitude along with b/a ratio of the combined rod-cone response were found between the young and adult animals as well as young and senile dogs. No significant differences were observed between the left and right eyes. ERG variables in beagle dogs differed by age due to age-related retinal changes. Thus, we propose that normal ERG ranges should be determined according to age in each clinic and laboratory using its own equipment because each institution usually has different systems or protocols for ERG testing.

Comparison of Electronic-Excitation-Induced Structural Modification of Carbon-Based Nanomaterials with that of Semiconductor Surfaces

Noriaki Itoh,Chihiro Itoh,Junichi Kanasaki 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.6

Modification by electronic excitation of semiconductor surfaces and carbon-related quasi-twodimensional (2D) nanostructured materials, namely graphene, carbon nanotubes is reviewed. Defect creation in these materials takes place not by low-intensity photoirradiation, but by laser or electron irradiation. The defect creation processes are different from ordinary photochemical processes in molecules or in some solids like alkali halides, which can be modified by a localized exciton. It is pointed out that there are common features in defect creation by electronic excitation in semiconductor surfaces and carbon-related quasi-2D nanomaterials: the yield-intensity relation shows strong superlinearity for laser irradiation near the bandgap energies and linearity or weak superlinearity for higher energy electron or photon irradiation. These results are explained in terms of multi-hole localization, in which bonds are weakened more strongly and more energy is available upon recombination with trapped electrons in comparison with excitons. The multi-hole localized state is considered to be realized by the creation of dense excitons or by cascade excitation for laser irradiation and by multiple excitations or multiple exciton generation by single impacts for electron irradiation. The review includes also polymerization of C60 films by electronic excitation, which is induced by low-intensity photoirradiation as well as by laser or electron irradiation. The experimental observation that laser or electron irradiation polymerize C60 films differently from low-intensity photoirradiation is explained in terms of multi-hole localization similar to the defect formation mechanism. Although fragmentation of C60 is due to electronic excitation of the molecule, it is included in the review because its yield is strongly superlinear for laser irradiation near bandgap energies and weakly superlinear for high-energy electron or photon irradiation as for other cases.

Global Geometry of Sasakian Manifolds

ITOH, MITSUHIRO 경북대학교 기초과학연구소 1999 International Workshop on Differential Geometry Vol.1999 No.-

Visualization of Underwater Sympathetic Detonation of High Explosives

Itoh, Shigeru,Hamada, Toru,Murata, Kenji,Kato, Yukio The Korean Society of Mechanical Engineers 2001 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.15 No.12

The experiment for the sympathetic detonation (Sudo et al., 1951) (Fukuyama et al., 1958) in water was conducted. Composition B (RDX: 64%, TNT: 36%, Detonation velocity: 7900m/s) was used for both donor (the thickness was 50mm, and the diameter was 31mm) and receptor charges. The distance between the donor and the receptor, and the thickness (5, 7.5, 10mm) of the receptor were varied in the experiments. In order to investigate the basic characteristics of the underwater sympathetic detonation of high explosive, the sympathetic detonation phenomena were visualized by a high-speed camera (HADLAND PHOTONICS, IMACON790) in forms of streak and framing photographs. The 200ns/mm streak velocity was 2㎲. Manganin gauges (KYOWA Electronic INSTRUMENTS CO. SKF-21725) were used for the pressure measurements. The gauges were set under the receptor. The pressures during the complete and incomplete explosions were measured.

Nonlinear collision analysis of heavy trucks onto steel highway guard fences

Itoh, Yoshito,Liu, Chunlu,Usami, Koichi Techno-Press 2001 Structural Engineering and Mechanics, An Int'l Jou Vol.12 No.5

The design specifications of guard fences in Japan were reexamined and the revised specifications were implemented from April 1999. Because of the huge consumption in time and cost to test the performances of full-scale guard fences in the field, some assumptions are adopted while modifying the design specifications, and numerical analyses are necessary to confirm the impact performance and safety level of new types of steel highway guard fences. In this study, the finite element models are developed for the heavy trucks and steel highway guard fences to reenact their behaviors, and the solution approach is carried out using nonlinear dynamic analysis software of structures in three dimensions (LS-DYNA). The numerical simulation results are compared with the full-scale on-site testing results to verify the proposed analysis procedure. The collision process is simulated and it is also made possible to visualize the movement of the truck and the performances of guard fences. In addition, the energy shift of the truck kinetic energy to the truck and guard fence Internal energy, and the energy absorption of each guard fence component are studied for the development of a new design methodology of steel highway guard fences based on the energy absorption capacity.

Otemachi(大手町) Sequential Urban Redevelopment Project

Itoh, Toshio Land and Housing Institute 2017 LHI journal of land, housing, and urban affairs Vol.8 No.2

Otemachi(大手町) is the region where it plays a pivotal role in Japanese economy as representative head offices of companies including financial insurance, general trading, information and communication newspaper media are concentrated. However, regenerating the entire region from worn-out infrastructures of buildings and city into the fresh and vibrant foothold in international business was the problem to be solved. In this situation, <Sequential Urban Redevelopment Project> was examined on the basis of administrative agencies and relevant enterprises to reconstruct office buildings in phases without ceasing business functions and activities by utilizing the large-scale vacant land occurred from the relocation of the national public institutions. The independent administrative institution 'Urban Renaissance Agency(UR)' has completed the examination of industrialization and participation request for the commencement of the project. In this article, The overview of <Otemachi Sequential Urban Redevelopment Project>, the new form of project promoted and cooperated by officials and people, is introduced by UR (Urban Renaissance Agency) reorganizing the land exchange and infrastructure through the land readjustment project, and at the same time, procuring capital and building office buildings in solidarity with private development enterprises and financial institutions.

Novel Frame Interpolation Method for High Image Quality LCDs

Itoh, Goh,Mishima, Nao The Korean Infomation Display Society 2004 Journal of information display Vol.5 No.3

We developed a novel frame interpolation method to interpolate a frame between two successive original frames. Using this method, we are able to apply a double-rate driving method instead of an impulse driving method where a black frame is inserted between two successive original frames. The double-rate driving method enables amelioration of the motion blur of LCDs caused by the characteristics of human vision without reducing the luminosity of the whole screen. The image quality of the double-rate driving method was also found to be better than that of an impulse driving method using our motion picture simulator and an actual panel. Our initial model of our frame interpolation method consists of motion estimation with a maximum matching pixel count estimation function, an area segmentation technique, and motion compensation with variable segmentation threshold. Although salt and pepper noise remained in a portion of an object mainly due to inaccuracy of motion estimation, we verified the validity of our method and the possibility of improvement in hold-type motion blurring.

THE MAXIMUM PRINCIPLE ON EINSTEIN-WEYL MANIFOLDS

ITOH, MITSUHIRO 경북대학교 기초과학연구소 1996 International Workshop on Differential Geometry Vol.1996 No.-