1,041 results on '"M, Ikegami"'
Search Results
2. Comparison of three aerosol representations of NHM-Chem (v1.0) for the simulations of air quality and climate-relevant variables
- Author
-
M. Kajino, M. Deushi, T. T. Sekiyama, N. Oshima, K. Yumimoto, T. Y. Tanaka, J. Ching, A. Hashimoto, T. Yamamoto, M. Ikegami, A. Kamada, M. Miyashita, Y. Inomata, S. Shima, P. Khatri, A. Shimizu, H. Irie, K. Adachi, Y. Zaizen, Y. Igarashi, H. Ueda, T. Maki, and M. Mikami
- Subjects
Geology ,QE1-996.5 - Abstract
This study provides comparisons of aerosol representation methods incorporated into a regional-scale nonhydrostatic meteorology–chemistry model (NHM-Chem). Three options for aerosol representations are currently available: the five-category non-equilibrium (Aitken, soot-free accumulation, soot-containing accumulation, dust, and sea salt), three-category non-equilibrium (Aitken, accumulation, and coarse), and bulk equilibrium (submicron, dust, and sea salt) methods. The three-category method is widely used in three-dimensional air quality models. The five-category method, the standard method of NHM-Chem, is an extensional development of the three-category method and provides improved predictions of variables relating to aerosol–cloud–radiation interaction processes by implementing separate treatments of light absorber and ice nuclei particles, namely, soot and dust, from the accumulation- and coarse-mode categories (implementation of aerosol feedback processes to NHM-Chem is still ongoing, though). The bulk equilibrium method was developed for operational air quality forecasting with simple aerosol dynamics representations. The total CPU times of the five-category and three-category methods were 91 % and 44 % greater than that of the bulk method, respectively. The bulk equilibrium method was shown to be eligible for operational forecast purposes, namely, the surface mass concentrations of air pollutants such as O3, mineral dust, and PM2.5. The simulated surface concentrations and depositions of bulk chemical species of the three-category method were not significantly different from those of the five-category method. However, the internal mixture assumption of soot/soot-free and dust/sea salt particles in the three-category method resulted in significant differences in the size distribution and hygroscopicity of the particles. The unrealistic dust/sea salt complete mixture of the three-category method induced significant errors in the prediction of the mineral dust-containing cloud condensation nuclei (CCN), which alters heterogeneous ice nucleation in cold rain processes. The overestimation of soot hygroscopicity by the three-category method induced errors in the BC-containing CCN, BC deposition, and light-absorbing aerosol optical thickness (AAOT). Nevertheless, the difference in AAOT was less pronounced with the three-category method because the overestimation of the absorption enhancement was compensated by the overestimation of hygroscopic growth and the consequent loss due to in-cloud scavenging. In terms of total properties, such as aerosol optical thickness (AOT) and CCN, the results of the three-category method were acceptable.
- Published
- 2021
- Full Text
- View/download PDF
3. The fast linear accelerator modeling engine for FRIB online model service.
- Author
-
Zhengqi He, M. Davidsaver, K. Fukushima, G. Shen, M. Ikegami, and J. Bengtsson
- Published
- 2019
- Full Text
- View/download PDF
4. Mutations close to a hub residue affect the distant active site of a GH1 β-glucosidase.
- Author
-
Valquiria P Souza, Cecília M Ikegami, Guilherme M Arantes, and Sandro R Marana
- Subjects
Medicine ,Science - Abstract
The tertiary structure of proteins has been represented as a network, in which residues are nodes and their contacts are edges. Protein structure networks contain residues, called hubs or central, which are essential to form short connection pathways between any pair of nodes. Hence hub residues may effectively spread structural perturbations through the protein. To test whether modifications nearby to hub residues could affect the enzyme active site, mutations were introduced in the β-glycosidase Sfβgly (PDB-ID: 5CG0) directed to residues that form an α-helix (260-265) and a β-strand (335-337) close to one of its main hub residues, F251, which is approximately 14 Å from the Sfβgly active site. Replacement of residues A263 and A264, which side-chains project from the α-helix towards F251, decreased the rate of substrate hydrolysis. Mutation A263F was shown to weaken noncovalent interactions involved in transition state stabilization within the Sfβgly active site. Mutations placed on the opposite side of the same α-helix did not show these effects. Consistently, replacement of V336, which side-chain protrudes from a β-strand face towards F251, inactivated Sfβgly. Next to V336, mutation S337F also caused a decrease in noncovalent interactions involved in transition state stabilization. Therefore, we suggest that mutations A263F, A264F, V336F and S337F may directly perturb the position of the hub F251, which could propagate these perturbations into the Sfβgly active site through short connection pathways along the protein network.
- Published
- 2018
- Full Text
- View/download PDF
5. Accelerator commissioning and rare isotope identification at the Facility for Rare Isotope Beams
- Author
-
J. Wei, H. Ao, B. Arend, S. Beher, G. Bollen, N. Bultman, F. Casagrande, W. Chang, Y. Choi, S. Cogan, C. Compton, M. Cortesi, J. Curtin, K. Davidson, X. Du, K. Elliott, B. Ewert, A. Facco, A. Fila, K. Fukushima, V. Ganni, A. Ganshyn, J. Gao, T. Glasmacher, J. Guo, Y. Hao, W. Hartung, N. Hasan, M. Hausmann, K. Holland, H. C. Hseuh, M. Ikegami, D. Jager, S. Jones, N. Joseph, T. Kanemura, S.-H. Kim, P. Knudsen, B. Kortum, E. Kwan, T. Larter, R. E. Laxdal, M. Larmann, K. Laturkar, J. LeTourneau, Z.-Y. Li, S. Lidia, G. Machicoane, C. Magsig, P. Manwiller, F. Marti, T. Maruta, A. McCartney, E. Metzgar, S. Miller, Y. Momozaki, D. Morris, M. Mugerian, I. Nesterenko, C. Nguyen, W. O’Brien, K. Openlander, P. N. Ostroumov, M. Patil, A. S. Plastun, J. Popielarski, L. Popielarski, M. Portillo, J. Priller, X. Rao, M. Reaume, H. Ren, K. Saito, M. Smith, M. Steiner, A. Stolz, O. B. Tarasov, B. Tousignant, R. Walker, X. Wang, J. Wenstrom, G. West, K. Witgen, M. Wright, T. Xu, Y. Xu, Y. Yamazaki, T. Zhang, Q. Zhao, S. Zhao, K. Dixon, M. Wiseman, M. Kelly, K. Hosoyama, and S. Prestemon
- Subjects
Nuclear and High Energy Physics ,Physics::Accelerator Physics ,General Physics and Astronomy ,Astronomy and Astrophysics ,Nuclear Experiment - Abstract
In 2008, Michigan State University was selected to establish the Facility for Rare Isotope Beams (FRIB). Construction of the FRIB accelerator was completed in January 2022. Phased accelerator commissioning with heavy ion beams started in 2017 with the normal-conducting ion source and radio-frequency quadrupole. In April 2021, the full FRIB driver linear accelerator (linac) was commissioned, with heavy ion beams accelerated to energies above 200 MeV/nucleon by 324 superconducting radiofrequency (SRF) resonators operating at 2 K and 4 K with liquid-helium cooling. In preparation for high-power operation, a liquid lithium charge stripper was commissioned with heavy ion beams up to uranium-238, followed by the simultaneous acceleration of multiple-charge-state heavy ion beams to energies above 200 MeV/nucleon. In December 2021, selenium-84 was produced with the FRIB target using a krypton-86 primary beam, demonstrating FRIB’s capability for scientific discovery.
- Published
- 2022
6. Using the Amino Acid Network to Modulate the Hydrolytic Activity of β-Glycosidases.
- Author
-
Fábio K Tamaki, Diorge P Souza, Valquiria P Souza, Cecilia M Ikegami, Chuck S Farah, and Sandro R Marana
- Subjects
Medicine ,Science - Abstract
The active site residues in GH1 β-glycosidases are compartmentalized into 3 functional regions, involved in catalysis or binding of glycone and aglycone motifs from substrate. However, it still remains unclear how residues outside the active site modulate the enzymatic activity. To tackle this question, we solved the crystal structure of the GH1 β-glycosidase from Spodoptera frugiperda (Sfβgly) to systematically map its residue contact network and correlate effects of mutations within and outside the active site. External mutations neighbouring the functional residues involved in catalysis and glycone-binding are deleterious, whereas mutations neighbouring the aglycone-binding site are less detrimental or even beneficial. The large dataset of new and previously characterized Sfβgly mutants supports that external perturbations are coherently transmitted to active site residues possibly through contacts and specifically disturb functional regions they interact to, reproducing the effects observed for direct mutations of functional residues. This allowed us to suggest that positions related to the aglycone-binding site are preferential targets for introduction of mutations aiming to further improve the hydrolytic activity of β-glycosidases.
- Published
- 2016
- Full Text
- View/download PDF
7. Three-dimensional variations of atmospheric CO2: aircraft measurements and multi-transport model simulations
- Author
-
M. Satoh, T. Oda, S. Maksyutov, R. Imasu, M. Ikegami, T. Maki, D. Belikov, T. Machida, H. Matsueda, P. K. Patra, Y. Sawa, Y. Niwa, and M. Takigawa
- Subjects
Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Numerical simulation and validation of three-dimensional structure of atmospheric carbon dioxide (CO2) is necessary for quantification of transport model uncertainty and its role on surface flux estimation by inverse modeling. Simulations of atmospheric CO2 were performed using four transport models and two sets of surface fluxes compared with an aircraft measurement dataset of Comprehensive Observation Network for Trace gases by AIrLiner (CONTRAIL), covering various latitudes, longitudes, and heights. Under this transport model intercomparison project, spatiotemporal variations of CO2 concentration for 2006–2007 were analyzed with a three-dimensional perspective. Results show that the models reasonably simulated vertical profiles and seasonal variations not only over northern latitude areas but also over the tropics and southern latitudes. From CONTRAIL measurements and model simulations, intrusion of northern CO2 in to the Southern Hemisphere, through the upper troposphere, was confirmed. Furthermore, models well simulated the vertical propagation of seasonal variation in the northern free troposphere. However, significant model-observation discrepancies were found in Asian regions, which are attributable to uncertainty of the surface CO2 flux data. In summer season, differences in latitudinal gradients by the fluxes are comparable to or greater than model-model differences even in the free troposphere. This result suggests that active summer vertical transport sufficiently ventilates flux signals up to the free troposphere and the models could use those for inferring surface CO2 fluxes.
- Published
- 2011
- Full Text
- View/download PDF
8. Reliability of polycrystalline silicon thin film resistors.
- Author
-
M. Nakabayashi, Hidenori Ohyama, Eddy Simoen, M. Ikegami, Cor Claeys, K. Kobayashi, M. Yoneoka, and K. Miyahara
- Published
- 2001
- Full Text
- View/download PDF
9. Comparison of three aerosol representations of NHM-Chem (v1.0) for the simulations of air quality and climate-relevant variables
- Author
-
M. Kajino, M. Deushi, T. T. Sekiyama, N. Oshima, K. Yumimoto, T. Y. Tanaka, J. Ching, A. Hashimoto, T. Yamamoto, M. Ikegami, A. Kamada, M. Miyashita, Y. Inomata, S. Shima, P. Khatri, A. Shimizu, H. Irie, K. Adachi, Y. Zaizen, Y. Igarashi, H. Ueda, T. Maki, and M. Mikami
- Subjects
QE1-996.5 ,food.ingredient ,Sea salt ,Geology ,General Medicine ,Mineral dust ,Atmospheric sciences ,medicine.disease_cause ,Soot ,Aerosol ,food ,Ice nucleus ,medicine ,Environmental science ,Cloud condensation nuclei ,Scavenging ,Air quality index - Abstract
This study provides comparisons of aerosol representation methods incorporated into a regional-scale nonhydrostatic meteorology–chemistry model (NHM-Chem). Three options for aerosol representations are currently available: the five-category non-equilibrium (Aitken, soot-free accumulation, soot-containing accumulation, dust, and sea salt), three-category non-equilibrium (Aitken, accumulation, and coarse), and bulk equilibrium (submicron, dust, and sea salt) methods. The three-category method is widely used in three-dimensional air quality models. The five-category method, the standard method of NHM-Chem, is an extensional development of the three-category method and provides improved predictions of variables relating to aerosol–cloud–radiation interaction processes by implementing separate treatments of light absorber and ice nuclei particles, namely, soot and dust, from the accumulation- and coarse-mode categories (implementation of aerosol feedback processes to NHM-Chem is still ongoing, though). The bulk equilibrium method was developed for operational air quality forecasting with simple aerosol dynamics representations. The total CPU times of the five-category and three-category methods were 91 % and 44 % greater than that of the bulk method, respectively. The bulk equilibrium method was shown to be eligible for operational forecast purposes, namely, the surface mass concentrations of air pollutants such as O3, mineral dust, and PM2.5. The simulated surface concentrations and depositions of bulk chemical species of the three-category method were not significantly different from those of the five-category method. However, the internal mixture assumption of soot/soot-free and dust/sea salt particles in the three-category method resulted in significant differences in the size distribution and hygroscopicity of the particles. The unrealistic dust/sea salt complete mixture of the three-category method induced significant errors in the prediction of the mineral dust-containing cloud condensation nuclei (CCN), which alters heterogeneous ice nucleation in cold rain processes. The overestimation of soot hygroscopicity by the three-category method induced errors in the BC-containing CCN, BC deposition, and light-absorbing aerosol optical thickness (AAOT). Nevertheless, the difference in AAOT was less pronounced with the three-category method because the overestimation of the absorption enhancement was compensated by the overestimation of hygroscopic growth and the consequent loss due to in-cloud scavenging. In terms of total properties, such as aerosol optical thickness (AOT) and CCN, the results of the three-category method were acceptable.
- Published
- 2020
10. Abstracts of presentations on plant protection issues at the xth international congress of virology: August 11-16, 1996 Binyanei haOoma, Jerusalem Iarael part 3(final part)
- Author
-
O. Faktor, G. P. Lomonossoff, S. Souche, B. Levine, C. Ford, D. Schumann, Sh. Abo-El-Saad, Fuh-Jyh Jan, F. Revere, J. Zalewski, M. Ravelonandro, M. Zaitlin, K. Lento, V. Hardi, V. Gaba, A. Romero, M. A. El-Saied, Michael J. Adams, O. N. Denisenko, M. Pilowsky, B. Böddi, W. Zagórski, M. Kikkert, J. Nahring, J. Peterka, U. Oertel, S. Seal, Kristin D. Kasschau, Susan Phillips, David C. Baulcombe, Michael G. K. Jones, S. A. MacFarlane, David M. Tricoli, Phil Larkin, M. A. Mayo, Maja Ravnikar, Patricio Arce-Johnson, H. Uchino, P. Bodegom, T. J. Higgins, Aiming Wang, Roger N. Beachy, T. Lin, M. I. Boulton, T. Natsuaki, S. Astier, A. de Kochko, E. Meiri, Marc G. Fortin, Orit Edelbaum, K. H. Hellwald, B. Falk, M. Ikegami, R. S. Zemetra, D. E. Purcifull, Rafael Rivera-Bustamante, X. W. Xiao, W. K. Kaniewski, M. M. Maugeri, Silvy Zeituny, N. H. Soliman, A. A. Brunt, S. Zimmermann, Hector D. Quemada, J. A. Daròs, I. Sela, I. Oukropec, Ab van Kammen, E. Dagless, R. Carson, P. de Haan, D. D. Shukla, P. J. Shiel, T. Ruiz-Perez, Darja Barlič Maganja, S. C. Taylor, Kristina Gruden, G. Salem, Varsha Wesley, D. L. Gellatly, V. Thole, H. Kawashima, E. Pehu, Erwin Cardol, P. Kominek, L. Mehlo, J. van Lent, K. Graichen, Frank Rabenstein, D. Robinson, J. Walter, M. Kelve, C. Porta, L. Tabe, M. El-Hariry, Johannes Fütterer, Stephen J. Wylie, A. Merits, Roger Hull, R. Goldbach, R. Arroyo, D. K. Becker, A. Ragozzino, H. Chatel, Velitchka Nikolaeva, J. F. Bol, N. Paltridge, G. I. Atiri, K. M. Taylor, A. N. Chiang, Andrew Wieczorek, K. H. Ryu, J. Polák, Y. Chupeau, J. C. Thouvenel, Daniel Plante, Na-Sheng Lin, J. Angel-Diaz, J. Porter, D. Gahakwa, A. Mooney, M. J. Frenkel, S. D. Wyatt, P. Chu, Brandt G. Cassidy, A. Van Schepen, G. R. Smith, A. R. De Rover, L. Sela, Y. Stram, Margarita Yankulova, T. Otsubo, O. Livneh, S. Tsuda, M. R. Hajimorad, J. E. Johnson, G. D. May, L. Levy, T. Candresse, Yan Yitang, Marilyn J. Roossinck, D. J. Hwang, C. M. Fauquet, J. J. L. Gielen, S. Lock, David Charles Baulcombe, B. J. Shi, M. Bitoova, Duk-Ju Hwang, E. Ham, V. M. Ursin, M. Barba, B. L. Barrón, Y. Kageyama, P. Palukaitis, Yau-Heiu Hsu, E. Aliskevicius, O. Le Gall, J. Antoniw, C. J. Arntzen, J. A. Sanchez-Navarro, T. Tamm, W. Chaleeprom, S. Dinant, S. Yu. Morozov, Biing-Yuan Lin, J. L. Badge, S. S. Bishnoi, J. L. Dale, R. Kormelink, N. E. Turner, J. P. T. Valkonen, A. E. Aboul-Ata, S. W. Ding, C. W. A. Pleij, Chu-Hui Chiang, Thomas Hohn, S. Kashiwazaki, F. Ponz, A. M. Chachulska, A. Almási, E. Vardi, J. M. Martínez-Zapater, E. Hiebert, P. Roy, Sheldon Cohen, J. Kunhara, M. Saarma, E. Truve, M. Taliansky, Marcel Prins, Joze Brzin, R. H. Symons, M. Leech, Sheng-Zhi Pang, D. A. Zelenina, M. Storms, M. Saito, M. Kinta, K. Tomaru, Peter de Haan, F. E. Christensen, J. Rathjen, S. J. Yang, E. Fuchs, A. Zelcer, I. B. Kaplan, E. C. Lawson, Hélène Sanfaçon, B. C. Rodoni, G. Mazithulela, Ching-Hsien Wang, M. Ekes, S. Wittmann, S. Schillberg, T. Maki-Valkama, E. Sivamani, M. Shams-Bakhsh, R. Turner, E. Mueller, Borut Štrukelj, M. Karamagioli, V. Somsap, A. Hernádez, A. Golshani, H. P. Loo, E. Ramirez, P. W. G. Chu, Colin W. Ward, T. B. Clifford, N. Collins, K. M. Makkouk, Amis Druka, G. D. Foster, T. Mitsky, M. F. Bateson, Igor Kregar, A. Mathews, Maria-Rosa Marano, L. Rasochova, James C. Carrington, C. A. Powell, K. Makinen, P. H. Berger, Mounir G. AbouHaidar, Nilgun Turner, J. J. English, F. Blaise, M. Q. J. M. Van Grinsven, Helen Rothnie, Frank Ratcliff, Rahat Makhdoom, Kim Carney, Y. M. Hou, R. L. Gilbertson, I. García-Luque, M. T. Serra, G. I. Dwyer, A. Murayama, Rob W. Goldbach, F. DiSerio, C. Jacquet, N. Banerjee, Stanislaw Flasinski, D. Twell, C. Kusiak, M. Chrzanowska, J. Feldman, Lidia Ivanova, Karma Carrier, John F. Bol, W. A. Miller, B. Raccah, J. A. Handley, J. Bachelier, T. Tamada, L. Nigul, R. N. Beachy, T. Kuittinen, R. Floras, A. K. Koenen, S. Guelemerov, Dennis Gonsalves, Joan Wellink, P. Gilardi, Monique M. van Oers, T. Kiguchi, L. Chen, Moshe Lapidot, G. Adam, D. H. L. Bishop, Ivan Ivanov, Shyi-Dong Yeh, G. Rodriguez-Alvarado, A. Callahan, G. Davenport, R. Stratford, B. Passmore, J. E. Faure, R. Gaborianvi, Gang Chen, Richard Kormelink, H. Huet, P. L. McCarthy, J. Drossard, Titia Sijen, R. Fischer, Z. Szigeti, P. Christou, D. Wolf, J. F. Laliberté, J. G. Atabekov, L. López, L. Tomassoli, B. A. L. M. Deiman, L. Kuznetsova, M. A. Wurscher, C. Robaglia, Q. Li, R. B. Sangwan, J. Dunez, R. M. Harding, Amit Gal-On, V. E. Spall, M. J. Soto, J. Hansen, N. Sugimura, C. A. Ong, G. P. Lodhi, Huub J. M. Linthorst, D. Li, R. Scorza, W. X. Li, Narayan Rishi, J. Schubert, M. Aulik, H. Lot, T. Kusume, R. Sanders, J. W. Davies, M. Satour, O. N. Fedorkin, G. A. Prody, M. V. Mikhailov, G. J. Hafner, Sandra Corsten, T. Pehu, Claire Huguenot, F. Garcia-Arenal, Y. P. Duan, D. Marshall, V. Pallas, A. Atanassov, P. Sithisarn-Burns, J. C. Bachelier, and J. Albouy
- Subjects
0106 biological sciences ,010602 entomology ,Insect Science ,Ecology (disciplines) ,International congress ,Physiology ,Library science ,Plant Science ,Biology ,01 natural sciences ,010606 plant biology & botany - Published
- 2018
11. Mutations close to a hub residue affect the distant active site of a GH1 β-glucosidase
- Author
-
Sandro R. Marana, Cecília M. Ikegami, Valquiria P. Souza, and Guilherme Menegon Arantes
- Subjects
0301 basic medicine ,Models, Molecular ,Cellobiose ,lcsh:Medicine ,medicine.disease_cause ,Biochemistry ,Physical Chemistry ,Nitrophenols ,Protein structure ,Catalytic Domain ,Macromolecular Structure Analysis ,Centrality ,Glycosides ,lcsh:Science ,Free Energy ,Mutation ,Multidisciplinary ,biology ,Transition (genetics) ,Beta-glucosidase ,Chemistry ,Hydrolysis ,Physics ,beta-Glucosidase ,Chemical Reactions ,Recombinant Proteins ,Reaction Dynamics ,Physical Sciences ,Thermodynamics ,Network Analysis ,Research Article ,Protein Structure ,Computer and Information Sciences ,MUTAÇÃO ,Spodoptera ,03 medical and health sciences ,Bacterial Proteins ,medicine ,Animals ,Molecular Biology ,Enzyme Assays ,Enzyme Kinetics ,Chemical Bonding ,lcsh:R ,Mutagenesis ,Active site ,Biology and Life Sciences ,Proteins ,Hydrogen Bonding ,Transition State ,biology.organism_classification ,Protein tertiary structure ,Protein Structure, Tertiary ,Kinetics ,030104 developmental biology ,Biophysics ,biology.protein ,Enzymology ,Mutagenesis, Site-Directed ,lcsh:Q ,Protein Structure Networks - Abstract
The tertiary structure of proteins has been represented as a network, in which residues are nodes and their contacts are edges. Protein structure networks contain residues, called hubs or central, which are essential to form short connection pathways between any pair of nodes. Hence hub residues may effectively spread structural perturbations through the protein. To test whether modifications nearby to hub residues could affect the enzyme active site, mutations were introduced in the β-glycosidase Sfβgly (PDB-ID: 5CG0) directed to residues that form an α-helix (260-265) and a β-strand (335-337) close to one of its main hub residues, F251, which is approximately 14 Å from the Sfβgly active site. Replacement of residues A263 and A264, which side-chains project from the α-helix towards F251, decreased the rate of substrate hydrolysis. Mutation A263F was shown to weaken noncovalent interactions involved in transition state stabilization within the Sfβgly active site. Mutations placed on the opposite side of the same α-helix did not show these effects. Consistently, replacement of V336, which side-chain protrudes from a β-strand face towards F251, inactivated Sfβgly. Next to V336, mutation S337F also caused a decrease in noncovalent interactions involved in transition state stabilization. Therefore, we suggest that mutations A263F, A264F, V336F and S337F may directly perturb the position of the hub F251, which could propagate these perturbations into the Sfβgly active site through short connection pathways along the protein network.
- Published
- 2018
12. Analysis of Compounds of Curcuma Rhizome Using Mass Spectrometry and Investigation of the Antioxidant Activity of Rhizome Extracts
- Author
-
H, Kasai, primary, Y, Yamane, additional, Kawai M, Ikegami, additional, and H, Sudo, additional
- Published
- 2019
- Full Text
- View/download PDF
13. Protein thermal denaturation is modulated by central residues in the protein structure network
- Author
-
Cecília M. Ikegami, Valquiria P. Souza, Guilherme Menegon Arantes, and Sandro R. Marana
- Subjects
Models, Molecular ,0301 basic medicine ,Protein Denaturation ,Protein Folding ,Circular dichroism ,Hot Temperature ,ENZIMAS HIDROLÍTICAS ,Protein Conformation ,Allosteric regulation ,Spodoptera ,010402 general chemistry ,01 natural sciences ,Biochemistry ,03 medical and health sciences ,Protein structure ,Enzyme Stability ,Animals ,Denaturation (biochemistry) ,Thermal stability ,Protein Interaction Maps ,Molecular Biology ,Chemistry ,Beta-glucosidase ,Circular Dichroism ,beta-Glucosidase ,Proteins ,Cell Biology ,Protein tertiary structure ,0104 chemical sciences ,Crystallography ,Spectrometry, Fluorescence ,030104 developmental biology ,Amino Acid Substitution ,Mutagenesis, Site-Directed ,Biophysics ,Insect Proteins ,Protein folding - Abstract
Network structural analysis, known as residue interaction networks or graphs (RIN or RIG, respectively) or protein structural networks or graphs (PSN or PSG, respectively), comprises a useful tool for detecting important residues for protein function, stability, folding and allostery. In RIN, the tertiary structure is represented by a network in which residues (nodes) are connected by interactions (edges). Such structural networks have consistently presented a few central residues that are important for shortening the pathways linking any two residues in a protein structure. To experimentally demonstrate that central residues effectively participate in protein properties, mutations were directed to seven central residues of the β-glucosidase Sfβgly (β-D-glucoside glucohydrolase; EC 3.2.1.21). These mutations reduced the thermal stability of the enzyme, as evaluated by changes in transition temperature (Tm ) and the denaturation rate at 45 °C. Moreover, mutations directed to the vicinity of a central residue also caused significant decreases in the Tm of Sfβgly and clearly increased the unfolding rate constant at 45 °C. However, mutations at noncentral residues or at surrounding residues did not affect the thermal stability of Sfβgly. Therefore, the data reported in the present study suggest that the perturbation of the central residues reduced the stability of the native structure of Sfβgly. These results are in agreement with previous findings showing that networks are robust, whereas attacks on central nodes cause network failure. Finally, the present study demonstrates that central residues underlie the functional properties of proteins.
- Published
- 2016
14. Test Methods for the Evaluation of Heavy Metals in Contaminated Soil
- Author
-
Hirofumi Sakanakura, Y. Kanjo, M. Ikegami, and Satoshi Mizutani
- Subjects
Standardization ,Soil water ,Extraction (chemistry) ,Environmental engineering ,Environmental science ,Heavy metals ,Leaching (agriculture) ,complex mixtures ,Environmental standard ,Soil contamination ,Test (assessment) - Abstract
Test methods for the evaluation of heavy metals contained in contaminated soil were summarized. The soil environmental standards, criteria for soils in each country, and setup backgrounds were studied. The methods for the extraction of heavy metals were classified into three categories: (1) digestion/decomposition, (2) extraction, and (3) leaching test. Regarding these three analytical methods, the scientific meaning of each method and concrete test procedures were described. Regarding the extraction method, the SCE (sequential chemical extraction) procedure for chemical forms of metals and extraction for bioavailability were discussed. In the section with regard to the leaching test, the relationship between operational factors and the leaching concentration was discussed and the availability test was also introduced. Furthermore, the movement of unifying the test methods in the ISO (International organization for standardization) was introduced. The environmental standards of soils and the criteria of 13 countries were compared. In addition, the setup backgrounds of the environmental standards and the environmental criteria for soils in Canada, Australia, the Netherlands, and Germany were investigated and discussed.
- Published
- 2016
15. Using the amino acid network to modulate the hydrolytic activity of beta-Glycosidases
- Author
-
Cecília M. Ikegami, Valquiria P. Souza, Diorge P. Souza, Sandro R. Marana, Chuck S. Farah, and Fábio K. Tamaki
- Subjects
0301 basic medicine ,Cellobiose ,Protein Conformation ,Mutant ,lcsh:Medicine ,Crystallography, X-Ray ,Biochemistry ,Pichia ,Protein structure ,Catalytic Domain ,Amino Acids ,lcsh:Science ,chemistry.chemical_classification ,Crystallography ,Multidisciplinary ,biology ,Chemistry ,Hydrolysis ,Physics ,Chemical Reactions ,Condensed Matter Physics ,ENZIMAS ,Enzymes ,Amino acid ,Deletion Mutation ,Physical Sciences ,Crystal Structure ,Sequence Analysis ,Research Article ,Multiple Alignment Calculation ,Glycoside Hydrolases ,Chemical physics ,Sequence alignment ,Spodoptera ,Research and Analysis Methods ,Catalysis ,03 medical and health sciences ,Computational Techniques ,Hydrolase ,Genetics ,Solid State Physics ,Animals ,Molecular Biology Techniques ,Sequencing Techniques ,Molecular Biology ,030102 biochemistry & molecular biology ,lcsh:R ,Biology and Life Sciences ,Proteins ,Active site ,Dimers (Chemical physics) ,biology.organism_classification ,Split-Decomposition Method ,030104 developmental biology ,Enzyme ,Mutation ,Enzymology ,biology.protein ,lcsh:Q ,Sequence Alignment - Abstract
The active site residues in GH1 β-glycosidases are compartmentalized into 3 functional regions, involved in catalysis or binding of glycone and aglycone motifs from substrate. However, it still remains unclear how residues outside the active site modulate the enzymatic activity. To tackle this question, we solved the crystal structure of the GH1 β-glycosidase from Spodoptera frugiperda (Sfβgly) to systematically map its residue contact network and correlate effects of mutations within and outside the active site. External mutations neighbouring the functional residues involved in catalysis and glycone-binding are deleterious, whereas mutations neighbouring the aglycone-binding site are less detrimental or even beneficial. The large dataset of new and previously characterized Sfβgly mutants supports that external perturbations are coherently transmitted to active site residues possibly through contacts and specifically disturb functional regions they interact to, reproducing the effects observed for direct mutations of functional residues. This allowed us to suggest that positions related to the aglycone-binding site are preferential targets for introduction of mutations aiming to further improve the hydrolytic activity of β-glycosidases.
- Published
- 2016
16. Visible light-sensitive MnO2- and CeO2-loaded ZrO2/carbon cluster/Pt nanocomposite materials
- Author
-
M. Ikegami, H. Matsui, Subbian Karuppuchamy, Mohd Ali Hassan, and Masakuni Yoshihara
- Subjects
Materials science ,Nanocomposite ,Aqueous solution ,chemistry.chemical_element ,Condensed Matter Physics ,law.invention ,Metal ,chemistry ,law ,visual_art ,visual_art.visual_art_medium ,Water splitting ,General Materials Science ,Calcination ,Irradiation ,Electrical and Electronic Engineering ,Carbon ,Visible spectrum ,Nuclear chemistry - Abstract
Nano-sized ZrO 2 /carbon cluster composite materials (I c ’s) were successfully prepared by the calcination of ZrOCl 2 /starch complex I. I c ’s were found to reduce methylene blue under the irradiation of visible light ( λ > 460 nm). The materials obtained by calcining at 400 and 500 °C were selectively loaded with Pt particles to obtain Pt-loaded ZrO 2 /carbon cluster composite materials denoted as I c400 Pt and I c500 Pt, respectively. In addition, the resultant materials were modified with MnO 2 and CeO 2 particles to achieve MnO 2 - and CeO 2 -loaded ZrO 2 /carbon cluster/Pt composite materials denoted as I c400 PtMn, I c500 PtMn, I c400 PtCe and I c500 PtCe, respectively. The metal oxides-loaded ZrO 2 /carbon cluster/Pt composite materials thus synthesized could decompose an aqueous silver nitrate solution by visible light irradiation to give Ag and O 2 with the [Ag]/[O 2 ] ratios of ca. 4. Visible light-irradiated water splitting examinations with I c400 PtMn and I c400 PtCe were also investigated and found to yield H 2 and O 2 with the [H 2 ]/[O 2 ] ratios of ca. 2.
- Published
- 2012
17. Three-dimensional variations of atmospheric CO2: aircraft measurements and multi-transport model simulations
- Author
-
Masaki Satoh, H. Matsueda, Prabir K. Patra, Masayuki Takigawa, Yousuke Sawa, Yosuke Niwa, Shamil Maksyutov, Toshinobu Machida, Dmitry Belikov, Ryoichi Imasu, Takashi Maki, M. Ikegami, and Tomohiro Oda
- Subjects
Atmospheric Science ,Carbon dioxide in Earth's atmosphere ,Computer simulation ,Seasonality ,Atmospheric sciences ,medicine.disease ,Physics::Geophysics ,Latitude ,Trace gas ,Troposphere ,Flux (metallurgy) ,Climatology ,medicine ,Environmental science ,Astrophysics::Earth and Planetary Astrophysics ,Southern Hemisphere ,Physics::Atmospheric and Oceanic Physics - Abstract
Numerical simulation and validation of three-dimensional structure of atmospheric carbon dioxide (CO2) is necessary for quantification of transport model uncertainty and its role on surface flux estimation by inverse modeling. Simulations of atmospheric CO2 were performed using four transport models and two sets of surface fluxes compared with an aircraft measurement dataset of Comprehensive Observation Network for Trace gases by AIrLiner (CONTRAIL), covering various latitudes, longitudes, and heights. Under this transport model intercomparison project, spatiotemporal variations of CO2 concentration for 2006–2007 were analyzed with a three-dimensional perspective. Results show that the models reasonably simulated vertical profiles and seasonal variations not only over northern latitude areas but also over the tropics and southern latitudes. From CONTRAIL measurements and model simulations, intrusion of northern CO2 in to the Southern Hemisphere, through the upper troposphere, was confirmed. Furthermore, models well simulated the vertical propagation of seasonal variation in the northern free troposphere. However, significant model-observation discrepancies were found in Asian regions, which are attributable to uncertainty of the surface CO2 flux data. In summer season, differences in latitudinal gradients by the fluxes are comparable to or greater than model-model differences even in the free troposphere. This result suggests that active summer vertical transport sufficiently ventilates flux signals up to the free troposphere and the models could use those for inferring surface CO2 fluxes.
- Published
- 2011
18. Characteristics of a laser-produced proton beam improved by a synchronous RF field
- Author
-
Yoshihisa Iwashita, Akira Noda, Hikaru Souda, Mamiko Nishiuchi, Shuji Kondo, Hiromitsu Kiriyama, H. Sugiyama, Akito Sagisaka, Hiroyuki Daido, Toshiyuki Shirai, Atsushi Akutsu, Akihisa Wakita, Yoshiki Nakai, Michiaki Mori, Alexander S. Pirozhkov, Tomohiro Motomura, Hiromu Tongu, Satoshi Orimo, Jinglong Ma, Koichi Ogura, Manabu Tanoue, Takuya Shimomura, Hiroshi Okada, Shuhei Kanazawa, Akifumi Yogo, and M. Ikegami
- Subjects
Physics ,Nuclear and High Energy Physics ,Proton ,business.industry ,Laser ,Synchrotron ,law.invention ,Pulsed laser deposition ,Acceleration ,Optics ,law ,Electric field ,Physics::Accelerator Physics ,Laser beam quality ,Atomic physics ,business ,Instrumentation ,Beam (structure) - Abstract
We have succeeded to compress the energy spread of a laser-produced proton beam to 1.6% at FWHM by an RF electric field synchronous to the pulse laser. Protons generated by this laser originally had a continuous energy spectrum with no peaks. Radial focusing and defocusing effects caused by the transverse component of the RF field were also observed. Concerning these effects, we simulated the energy spectra from the calculated value of the electric field by POISSON; the simulation could almost reproduce the experimental results. By applying this beam as an injection beam of a synchrotron, a compact acceleration system for particle cancer therapy is expected to be realized.
- Published
- 2009
19. RNA silencing in plants and its suppression by plant viruses
- Author
-
T. Kon and M. Ikegami
- Subjects
Small interfering RNA ,General Veterinary ,RNA-induced silencing complex ,fungi ,Trans-acting siRNA ,RNA ,Argonaute ,Biology ,Virology ,RNA silencing ,RNA interference ,Plant virus ,General Agricultural and Biological Sciences ,Nature and Landscape Conservation - Abstract
RNA silencing is a sequence-specific degradation of RNA and a means of regulation of gene expression via small RNA molecules. In plants, this process is commonly referred to as post-transcriptional gene silencing (PTGS). PTGS is characterized by accumulation of small-interfering RNAs (siRNAs) and microRNAs (miRNAs), degradation of target mRNAs and methylation of homologous gene sequences. In addition to gene regulation, PTGS also plays an important role as an immunity system in plants, which acts against diverse molecular parasites or foreign genetic elements including transposons, transgenes, viruses and viroids. Most plant viruses have evolved the capacity to counteract this defence response by encoding suppressors of PTGS. Viral suppressors are highly diverse in sequence and act at distinct steps in PTGS. Furthermore, the relative ability of viral suppressors to interfere with PTGS in plants can be associated with pathogenicity. In this review, we focus on recent advances in understanding RNA silencing and its suppression by plant viruses.
- Published
- 2009
20. Limited distribution of gravitation abscess caused by infected preauricular sinus depends on anatomical structure
- Author
-
Kiyoshi Matsuo, Hiroshi Shinohara, M. Ikegami, R. Ban, and Y. Tanaka
- Subjects
medicine.medical_specialty ,business.industry ,Epidermoid cyst ,Anatomy ,medicine.disease ,Subcutaneous fat ,Surgery ,Plastic surgery ,medicine.anatomical_structure ,Cadaver ,Superior auricular ligament ,otorhinolaryngologic diseases ,medicine ,Zygomatic arch ,Abscess ,business ,Sinus (anatomy) - Abstract
The anatomical causes underlying the distribution pattern of abscesses due to the preauricular sinus are presented together with a retrospective study of affected patients. The distribution of the preauricular sinus opening and the abscess position in 27 patients was investigated. To confirm the anatomical factors affecting abscess distribution, auricular and preauricular tissues of cadavers were microscopically and macroscopically examined. Twenty-three of 27 abscesses were concentrated in the preauricular region away from the area where the subcutaneous fat was thick. One was found in the crus helix, and the other three were found in the sinus opening. The preauricular subcutaneous fat layer was contained posteriorly and caudally by the spine of helix, superior auricular ligament, and zygomatic arch. The abscess tended to gravitate toward the preauricular fat layer and it may be misdiagnosed as an infected epidermoid cyst.
- Published
- 2008
21. Analysis of Volatile Compounds of Curcuma longa (Turmeric) and Investigation of the Antioxidant Activity of Rhizome Extracts
- Author
-
H, Ishii, primary, H, Yaoita, additional, Kawai M, Ikegami, additional, and H, Kasai, additional
- Published
- 2017
- Full Text
- View/download PDF
22. High-Quality Laser-Produced Proton Beam Realized by the Application of a Synchronous RF Electric Field
- Author
-
Akira Noda, Satoshi Orimo, Hiroyuki Daido, Toshiyuki Shirai, Hikaru Souda, Michiaki Mori, Yukio Hayashi, Sergei V. Bulanov, Hiromu Tongu, Shu Nakamura, Mamiko Nishiuchi, Akira Nagashima, Akito Sagisaka, Timur Zh. Esirkepov, A. Fukumi, Alexander S. Pirozhkov, Toyoaki Kimura, Takeshi Takeuchi, M. Ikegami, Z. Li, Masataka Kado, Yoshihisa Iwashita, Koichi Ogura, Toshiki Tajima, and Akifumi Yogo
- Subjects
Physics ,Physics and Astronomy (miscellaneous) ,Proton ,business.industry ,General Engineering ,Analytical chemistry ,General Physics and Astronomy ,Laser ,law.invention ,Intensity (physics) ,Acceleration ,Optics ,Amplitude ,law ,Electric field ,Laser power scaling ,business ,Beam (structure) - Abstract
A short-pulse (~210 fs) high-power (~1 TW) laser was focused on a tape target 3 and 5 µm in thickness to a size of 11×15 µm2 with an intensity of 3×1017 W/cm2. Protons produced by this laser with an energy spread of 100% were found to be improved to create peaks in the energy distribution with a spread of ~7% by the application of the RF electric field with an amplitude of ±40 kV synchronous to the pulsed laser. This scheme combines the conventional RF acceleration technique with laser-produced protons for the first time. It is possible to be operated up to 10 Hz, and is found to have good reproducibility for every laser shot with the capability of adjusting the peak positions by control of the relative phase between the pulsed laser and the RF electric field.
- Published
- 2007
23. Single droplet combustion of decane in microgravity: experiments and numerical modelling
- Author
-
D. L. Dietrich, P. M. Struk, M. Ikegami, and G. Xu
- Subjects
Fuel Technology ,Modeling and Simulation ,General Chemical Engineering ,General Physics and Astronomy ,Energy Engineering and Power Technology ,General Chemistry - Published
- 2005
24. Optimization of lattice quadrupole magnets for cooler ring, S-LSR
- Author
-
M. Ikegami, Toshiyuki Shirai, Hiromu Tongu, Hicham Fadil, Akira Noda, Koji Noda, Takeshi Takeuchi, Yoshihisa Iwashita, and Shinji Shibuya
- Subjects
Physics ,Nuclear and High Energy Physics ,Condensed matter physics ,Magnetostatics ,Computational physics ,Magnetic field ,Ion ,Electromagnetic induction ,Lattice (order) ,Electromagnetic shielding ,Physics::Accelerator Physics ,Boundary value problem ,Quadrupole magnet ,Instrumentation - Abstract
Design of quadrupole magnets for a compact ion accumulation and cooler ring, S-LSR, is presented. By requirements from lattice parameters and spatial boundaries for real installation in S-LSR, quadrupole magnets with relatively short magnetic length but wide horizontal aperture are needed. In this paper, we present results obtained from magnetic field calculations by 2D and 3D modelings, and describe the optimization of a pole face shape and fringing edge (chamfer cut design).
- Published
- 2004
25. Design and Measurement of the S-LSR Quadrupole Magnet Considering the Influence of a Neighboring Field Clamp
- Author
-
Hiromu Tongu, T. Shirai, Akira Noda, Shinji Shibuya, H. Fadil, M. Ikegami, K. Noda, Yoshihisa Iwashita, and T. Takeuchi
- Subjects
Physics ,Field (physics) ,Superconducting magnet ,Condensed Matter Physics ,Magnetic flux ,Electronic, Optical and Magnetic Materials ,Computational physics ,Magnetic field ,Nuclear magnetic resonance ,Dipole magnet ,Magnet ,Quadrupole ,Physics::Accelerator Physics ,Electrical and Electronic Engineering ,Quadrupole magnet ,Astrophysics::Galaxy Astrophysics - Abstract
The design and the magnetic field measurement of the quadrupole magnet for the compact ion ring, S-LSR, are presented. Because the S-LSR is a compact ring accelerator, whose components take up most of the space in the arc sections. Therefore, we have to optimize the integrated field gradient in the quadrupole magnetic field taking account of the effect of the neighboring field clamp. Under these conditions plus requirements from accelerator parameters, the design of the S-LSR quadrupole magnet was optimized by means of 2D and 3D modeling calculations. A magnet field measurement by a Hall probe is carried out together with the field clamp and S-LSR bending magnet. Both results of the calculation and the measurement present the almost same result as that for the effect of the field clamp.
- Published
- 2004
26. Aircraft Observation of CO2, CO, O3 and H2 over the North Pacific during the PACE-7 Campaign
- Author
-
Y. SAWA, H. MATSUEDA, Y. MAKINO, H. Y. INOUE, S. MURAYAMA, M. HIROTA, Y. TSUTSUMI, Y. ZAIZEN, M. IKEGAMI, and K. OKADA
- Subjects
Atmospheric Science - Published
- 2004
27. Genetic evolution of fetoprotein producing gastric cancer
- Author
-
K Ichikawa, M Ikegami, Tadakazu Shimoda, Hiroaki Fujii, T Takagaki, Y Nakanishi, and S Hirose
- Subjects
Adult ,Male ,Heterozygote ,Pathology ,medicine.medical_specialty ,Clone (cell biology) ,Loss of Heterozygosity ,Biology ,Somatic evolution in cancer ,Pathology and Forensic Medicine ,Evolution, Molecular ,Loss of heterozygosity ,Stomach Neoplasms ,Pancreatic cancer ,medicine ,Carcinoma ,Humans ,neoplasms ,Aged ,digestive, oral, and skin physiology ,Homozygote ,Cancer ,Original Articles ,General Medicine ,Middle Aged ,medicine.disease ,Immunohistochemistry ,digestive system diseases ,Phenotype ,Adenocarcinoma ,Female ,alpha-Fetoproteins ,Microsatellite Repeats - Abstract
Background: α Fetoprotein (AFP) producing gastric cancer is an unusual form of aggressive adenocarcinoma with a complex histological picture, including enteroblastic and hepatoid differentiation. Aims: To investigate the genetic events underlying the phenotypic diversity in AFP producing gastric cancer and the ability of these tumours to produce AFP ectopically. Methods: Multiple foci from 19 AFP producing gastric adenocarcinomas were microdissected and loss of heterozygosity (LOH) analysis was performed with a panel of microsatellite markers on nine chromosomal arms. Results: For informative cases, LOH was most frequently detected on 17p (100%), followed by 13q (88%), 3p (87%), 5q and 9p (80%), 11q (70%), 18q (58%), 16q (53%), and 8p (50%). The average fractional allelic loss was 0.72. LOH was detected either homogeneously throughout the microdissected foci, or only in some parts of the neoplastic foci for each case. Heterogeneous patterns of LOH indicated genetic progression and/or divergence in clonal evolution. Furthermore, in six cases with heterogeneous LOH of 13q, 13q LOH was restricted to immunohistochemically AFP positive neoplastic foci. Conclusion: AFP-GC arises as an aggressive clone with extensive LOH and high fractional allelic loss. The presence of heterogeneous patterns of LOH suggested that the AFP producing carcinoma foci might evolve through genetic progression and/or genetic divergence. Silencing of the crucial gene on 13q may be involved in the acquisition of the AFP producing phenotype.
- Published
- 2003
28. Effects of mechanical stress on polycrystalline-silicon resistors
- Author
-
K Miyahara, M. Ikegami, Eddy Simoen, Corneel Claeys, Kiyoshi Kobayashi, M Nakabayashi, H. Ohyama, and M. Yoneoka
- Subjects
inorganic chemicals ,Materials science ,Silicon ,business.industry ,Doping ,technology, industry, and agriculture ,Metals and Alloys ,Mineralogy ,chemistry.chemical_element ,Surfaces and Interfaces ,Chemical vapor deposition ,engineering.material ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Stress (mechanics) ,Semiconductor ,Polycrystalline silicon ,chemistry ,Materials Chemistry ,engineering ,Wafer ,Composite material ,Boron ,business - Abstract
Results are presented of a study on the mechanical stress dependence of the resistance of polycrystalline silicon (Poly-Si) films doped with different atomic species, namely, with boron and phosphorus ions. B-doped films of 400 nm and P-doped films of 250 nm thickness were deposited by low-pressure chemical vapor deposition at 620 °C on thermally oxidized silicon wafers. A controlled amount of external stress was applied to the silicon wafers in order to investigate the impact on the electrical performance of the implanted Poly-Si resistors. The resistance of the B-doped Poly-Si films is shown to increase by the mechanical stress, while the resistance of the P-implanted Poly-Si films remained unchanged. It is concluded that this difference is related to the structural differences between Poly-Si films implanted with boron and phosphorus, respectively.
- Published
- 2002
29. Mechanical stress of the electrical performance of polycrystalline-silicon resistors
- Author
-
C. Claeys, K. Kobayashi, M. Yoneoka, Eddy Simoen, N. Nakabayashi, H. Ohyama, K Miyahara, and M. Ikegami
- Subjects
Materials science ,Mechanical Engineering ,Doping ,chemistry.chemical_element ,Chemical vapor deposition ,engineering.material ,Condensed Matter Physics ,Ion ,Stress (mechanics) ,Ion implantation ,Polycrystalline silicon ,chemistry ,Mechanics of Materials ,engineering ,General Materials Science ,Wafer ,Composite material ,Boron - Abstract
Results are presented of a study on the mechanical stress dependence of the resistance of polycrystalline silicon (Poly-Si) films doped with different atomic species. Two types of Poly-Si film implanted with boron and phosphorus ions were studied, namely, B-doped films of 400 nm and P-doped films of 250 nm thickness, which were deposited by low-pressure chemical vapor deposition at 620 °C on thermally oxidized silicon wafers. The film doping was done by ion implantation at 50 keV, with a dose of boron and phosphorus of 2 × 1014 and 5.3 × 1014 cm−2, respectively. The Poly-Si films were annealed in a N2 ambient at 1000 °C for 20 min to activate the implanted atoms. A controlled amount of external stress was applied to the silicon wafers to study the impact on the electrical performance of the implanted Poly-Si resistors. The resistance of the B-doped Poly-Si films is shown to increase by the mechanical stress, while the resistance of the P-implanted Poly-Si films remained unchanged. It is concluded that this difference is related to the structural differences between Poly-Si films implanted with boron and phosphorus, respectively.
- Published
- 2001
30. Reliability of polycrystalline silicon thin film resistors
- Author
-
K Miyahara, Eddy Simoen, Corneel Claeys, K Kobayashi, M Ikegami, M Nakabayashi, M Yoneoka, and Hidenori Ohyama
- Subjects
Materials science ,business.industry ,Nanocrystalline silicon ,engineering.material ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,law.invention ,Monocrystalline silicon ,Reliability (semiconductor) ,Polycrystalline silicon ,law ,engineering ,Optoelectronics ,Electrical and Electronic Engineering ,Resistor ,Thin film ,Safety, Risk, Reliability and Quality ,business - Published
- 2001
31. Negative Photoconductivity in Polycrystalline Silicon Films Doped with Phosphorus
- Author
-
H. Takizawa, Cor Claeys, Y. Takami, Masashi Nakabayashi, M. Yoneoka, Hiromi Sunaga, M. Ikegami, Hidenori Ohyama, K. Kobayashi, K. Miyahara, and Eddy Simoen
- Subjects
Materials science ,Hydrogen ,Photoconductivity ,Phosphorus ,Doping ,chemistry.chemical_element ,engineering.material ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Polycrystalline silicon ,chemistry ,Chemical engineering ,engineering ,General Materials Science - Published
- 2001
32. Clinicopathological features of narrow-band imaging endoscopy and immunohistochemistry in ultraminute esophageal squamous neoplasms
- Author
-
K, Goda, A, Dobashi, N, Yoshimura, M, Chiba, A, Fukuda, Y, Nakao, T R, Ohya, Y, Sasaki, M, Kato, H, Aihara, K, Sumiyama, H, Toyoizumi, T, Kato, H, Tajiri, and M, Ikegami
- Subjects
Male ,Esophageal Neoplasms ,Iodides ,Middle Aged ,Immunohistochemistry ,Narrow Band Imaging ,Ki-67 Antigen ,Biomarkers, Tumor ,Carcinoma, Squamous Cell ,Humans ,Female ,Esophagoscopy ,Tumor Suppressor Protein p53 ,Coloring Agents ,Carcinoma in Situ ,Aged ,Retrospective Studies - Abstract
To reveal clinicopathological features of narrow-band imaging (NBI) endoscopy and immunohistochemistry in ultraminute esophageal squamous neoplasms. If a lesion diameter was smaller or same compared with a width of closed biopsy forceps, a lesion was defined to be an ultraminute lesion. Twenty-five consecutive patients with 33 ultraminute esophageal lesions that were removed by endoscopic mucosal resection were included in the present study. We conducted two questionnaire surveys of six endoscopists by their retrospective review of endoscopic still images. The six endoscopists evaluated the endoscopic findings of the ultraminute lesions on still images taken by conventional white-light imaging endoscopy and non-magnified NBI endoscopy in the first questionnaire, and taken by magnified NBI endoscopy in the second questionnaire. An experienced pathologist who was unaware of any endoscopic findings made histological diagnosis and evaluated immunoexpression of p53 and Ki67. The 33 ultraminute lesions were all determined to be either 11 high-grade intraepithelial neoplasias (HGIENs) or 22 low-grade intraepithelial neoplasias (LGIENs). The tumor diameters were histologically confirmed to be3 mm. All of the ultraminute tumors were visualized as unstained areas and brownish areas by real-time endoscopy with Lugol dye staining and non-magnified NBI endoscopy, respectively. All of the ultraminute IENs were visualized as brownish areas by real-time non-magnified NBI endoscopy. Three of the 25 patients with the ultraminute IENs (12%) had multiple brownish areas (more than several areas) in the esophagus on real-time non-magnified NBI endoscopy. All of the ultraminute IENs were visualized as unstained areas by real-time Lugol chromoendoscopy. Twenty of the 25 patients (80%) had multiple unstained areas (more than several areas) in the esophagus on real-time Lugol chromoendoscopy. The first questionnaire survey revealed that a significantly higher detection rate of the ultraminute IENs on non-magnified NBI endoscopy images compared with conventional white-light imaging endoscopy ones (100% vs. 72%, respectively: P0.0001). The second questionnaire survey revealed that presence rates of any magnified NBI endoscopy findings were not significantly different between HGIENs and LGIENs. Proliferation, dilation, and various shapes of intrapapillary capillary loops indicated remarkably high presence rates of more than 90% in both HGIENs and LGIENs. Six of 22 LGIENs (27%) and 3 of 11 HGIENs (27%) show a positive expression for p53. None of peri-IEN epithelia was positive for p53. A mean of Ki67 labeling index of LGIENs was 33% and that of HGIENs 36%. Ki67 labeling index was significantly greater in the LGIENs and HGIENs compared with that in the peri-IEN epithelia. There were no significant differences in p53 expression and Ki67 labeling index between the HGIENs and LGIENs. Non-magnified/magnified NBI endoscopy could facilitate visualization and characterization of ultraminute esophageal squamous IENs. The ultraminute HGIENs and LGIENs might have comparable features of magnified NBI endoscopy and immunohistochemistry.
- Published
- 2013
33. Climate change, wine, and conservation
- Author
-
Hannah, P.R. Roehrdanz, M. Ikegami, A. V. Shepard, M. R. Shaw, G. Tabor, L. Zhi, and P. A. Marquet & R. J. Hijmans
- Published
- 2013
34. Change in properties of exogenous surfactant in injured rabbit lung
- Author
-
M Ikegami and T Ueda
- Subjects
Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Lung injury ,Critical Care and Intensive Care Medicine ,Nitrosomethylurethane ,Pulmonary surfactant ,In vivo ,Internal medicine ,medicine ,Animals ,Centrifugation ,Lung ,Biological Products ,Lagomorpha ,biology ,Respiratory distress ,business.industry ,Pulmonary Surfactants ,biology.organism_classification ,Blood proteins ,Endocrinology ,medicine.anatomical_structure ,Anesthesia ,Rabbits ,business - Abstract
We asked if the function of surfactant could be enhanced after exposure to injured lungs. We also asked if sensitivity to inhibition of the minimal surface-tension-lowering properties of surfactant by plasma could be altered. Lung injury in rabbits was induced with N-nitroso-N-methylurethane (NMU) and 6 of 17 NMU-injured rabbits were treated with 100 mg/kg surfactant. All rabbits were ventilated for 2 h, and large aggregate alveolar surfactant was isolated by centrifugation. In vivo function of the large aggregate surfactant was evaluated by treatment of preterm surfactant-deficient rabbits at 27 d gestation. Surfactant from NMU-injured lungs increased compliance from 0.37 +/- 0.01 in control preterm rabbits to 0.71 +/- 0.05, a value significantly higher than found for the surfactant used for treatment (0.55 +/- 0.04) (p0.05). The minimal surface tensions of large aggregate surfactant and the surfactant used for treatment (0.1 mg lipid/ml) were evaluated for inhibition by plasma proteins. Surfactant from NMU-injured and surfactant-treated rabbits was more resistant to inhibition (minimal surface tension, 5.7 +/- 3.9 dyne/cm in the presence of 0.6 mg/ml plasma protein) than the surfactant used for treatment (19.7 +/- 0.8 dyne/cm). These results indicate that after exposure to the injured lung, the function of the surfactant used for treatment was enhanced and made less sensitive to plasma inhibition of the surface-tension-lowering properties of surfactant. These changes probably result from the association of endogenous surfactant components with exogenous surfactant.
- Published
- 1996
35. Clearance of surfactant protein A from rabbit lungs
- Author
-
A H Jobe, T. Ueda, and M Ikegami
- Subjects
Pulmonary and Respiratory Medicine ,Pulmonary Surfactant-Associated Proteins ,1,2-Dipalmitoylphosphatidylcholine ,Metabolic Clearance Rate ,Proteolipids ,Clinical Biochemistry ,Lamellar granule ,Biology ,Iodine Radioisotopes ,chemistry.chemical_compound ,Pulmonary surfactant ,In vivo ,Macrophages, Alveolar ,Animals ,Lung ,Molecular Biology ,Organelles ,Pulmonary Surfactant-Associated Protein A ,technology, industry, and agriculture ,Pulmonary Surfactants ,Cell Biology ,Metabolism ,Molecular biology ,Surfactant protein A ,Pulmonary Alveoli ,Adult rabbit ,chemistry ,Biochemistry ,Dipalmitoylphosphatidylcholine ,Female ,lipids (amino acids, peptides, and proteins) ,Rabbits ,Clearance - Abstract
Surfactant protein A (SP-A) is a major surfactant protein with multiple biophysical, metabolic, and host defense functions. To further characterize its metabolism in vivo, we measured clearance of SP-A from adult rabbit lungs. Trace amounts of [125I]SP-A radiolabeled by the Bolton-Hunter method and mixed with [3H]dipalmitoylphosphatidylcholine (DPPC) were given intratracheally via a bronchoscope to rabbits. Groups of five to six animals were studied 10 min to 16 h after labeled surfactant administration. After collection of alveolar washes, lamellar bodies were isolated from lung tissue. Macrophages also were isolated from alveolar washes. [125I]SP-A was cleared more rapidly than DPPC from the airspaces. Both [125I]SP-A and [3H]DPPC were lost exponentially from the total lungs, with half-life values of 6.5 h for SP-A and 12 h for DPPC (P0.01). In macrophages, the highest radioactivities for SP-A and DPPC were at 10 to 45 min and the radiolabels subsequently disappeared similarly. In lamellar bodies, 125I and 3H radioactivities per mumol saturated phosphatidylcholine (Sat PC) increased in parallel and were highest at 2 h. Whereas radiolabeled lipids were recovered in lamellar bodies for up to 16 h, iodinated SP-A was lost, indicating less recycling of SP-A than DPPC. We previously showed independent pathways of SP-A and Sat PC secretion in rabbits. These results demonstrate the different clearance kinetics of these two principle components of surfactant.
- Published
- 1995
36. Fetal corticosteroid and T4 treatment effects on lung function of surfactant-treated preterm lambs
- Author
-
M. Ikegami, Chung Ming Chen, Alan H. Jobe, T. Ueda, and Daniel H. Polk
- Subjects
Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,medicine.drug_class ,medicine.medical_treatment ,Gestational Age ,Critical Care and Intensive Care Medicine ,Betamethasone ,Random Allocation ,Fetus ,Pulmonary surfactant ,Internal medicine ,medicine ,Animals ,Drug Interactions ,Lung volumes ,Lung ,Saline ,Sheep ,business.industry ,Gestational age ,Pulmonary Surfactants ,Respiratory Function Tests ,Thyroxine ,Endocrinology ,Corticosteroid ,Female ,Rabbits ,Intramuscular injection ,business ,medicine.drug - Abstract
Three groups of sheep fetuses at 125 or 126 d gestational age randomly received a single ultrasound-guided intramuscular injection of saline, 0.5 mg/kg betamethasone, or 0.5 mg/kg betamethasone plus 50 micrograms/kg thyroxine (T4). Forty-eight hours later the fetuses were delivered, treated with a pulmonary surfactant preparation, and ventilated for 3 h. Corticosteroids alone and in combination with T4 increased FRC, compliance, and lung volumes, and decreased the protein leak into the airspace. Saturated phosphatidylcholine pool sizes recovered by alveolar washing were not changed after hormone treatment. To evaluate the function of surfactant recovered from the lambs in vivo, we treated preterm rabbits at 27 d gestational age with the large-aggregate surfactant from alveolar washes. Large-aggregate surfactants and the pulmonary surfactant preparation increased compliances and maximal lung volumes relative to those in untreated preterm rabbits. Large-aggregate surfactants improved compliance more than did the pulmonary surfactant preparation. We conclude that ultrasound-guided single fetal corticosteroid treatment followed by postnatal surfactant improved postnatal lung function in preterm lambs. Addition of T4 did not augment corticosteroid effects. The function of the exogenous surfactant was improved in premature lamb lungs independently of the fetal treatment modality.
- Published
- 1995
37. Spreading characteristics of cyclotriphosphazine-terminated perfluoropolyether films on carbon surfaces
- Author
-
M. Ikegami, N. Kobayashi, T. Tateyama, Y. Fujii, Atsunobu Mori, and Norio Tagawa
- Subjects
Materials science ,Diffusion ,Perfluoropolyether ,chemistry.chemical_element ,Electronic, Optical and Magnetic Materials ,chemistry ,Ellipsometry ,Monolayer ,Lubrication ,Wetting ,Electrical and Electronic Engineering ,Composite material ,Lubricant ,Carbon - Abstract
Spreading characteristics of novel cyclotriphosphazine-terminated perfluoropolyether (PFPE) films on carbon surfaces were investigated experimentally by using a scanning microellipsometer. The apparent diffusion coefficients of novel lubricants were also studied in order to evaluate the spreading speed, and they were compared with the conventional Zdol. It was found that the mobility of cyclotriphosphazine-terminated PFPE films is lower than that of Zdol. In addition, the monolayer film thickness of novel lubricant films as well as conventional Zdol was identified, which was extracted using the Matano interface method. As a result, it was found that the end groups affect the monolayer film thickness and the existing conformation of novel cyclotriphosphazine-terminated PFPE film on carbon surfaces could be estimated.
- Published
- 2003
38. Phosphorylation of Dynamin by CDC2 Kinase
- Author
-
M. Ikegami, Masaki Inagaki, K. Yazaki, Hiroshi Hosoya, Takahiko Shimizu, and Satoshi Komatsu
- Subjects
Dynamins ,inorganic chemicals ,endocrine system ,Biophysics ,macromolecular substances ,Microtubules ,Biochemistry ,GTP Phosphohydrolases ,Phosphates ,Serine ,Phosphoserine ,Microtubule ,CDC2 Protein Kinase ,Animals ,Humans ,Phosphorylation ,Binding site ,Molecular Biology ,Polyacrylamide gel electrophoresis ,Dynamin ,Brain Chemistry ,Cyclin-dependent kinase 1 ,Binding Sites ,Chemistry ,Kinase ,Cell Biology ,Rats ,Cell biology ,Microscopy, Electron ,enzymes and coenzymes (carbohydrates) ,Electrophoresis, Polyacrylamide Gel ,biological phenomena, cell phenomena, and immunity ,HeLa Cells - Abstract
A 100kD microtubule-bundling protein dynamin was phosphorylated in vitro by cdc2 kinase to approximately 1 mol of phosphate/mol of dynamin at a serine residue. These phosphorylations of dynamin greatly reduced its binding ability to microtubules.
- Published
- 1994
39. Developmental changes of sheep surfactant: in vivo function and in vitro subtype conversion
- Author
-
T. Ueda, M. Ikegami, and A. H. Jobe
- Subjects
Aging ,Pulmonary Surfactant-Associated Proteins ,Physiology ,Proteolipids ,Gestational Age ,Biology ,Andrology ,chemistry.chemical_compound ,Oxygen Consumption ,Pulmonary surfactant ,In vivo ,Physiology (medical) ,Phosphatidylcholine ,Animals ,Humans ,Lung volumes ,Lung Compliance ,Respiratory Distress Syndrome, Newborn ,Sheep ,Developmental age ,Body Weight ,Infant, Newborn ,Gestational age ,Pulmonary Surfactants ,Carbon Dioxide ,Hydrogen-Ion Concentration ,In vitro ,Pulmonary Alveoli ,Animals, Newborn ,chemistry ,Immunology ,Phosphatidylcholines ,Rabbits ,Function (biology) - Abstract
Developmental differences in the intrinsic characteristics of surfactant have not been evaluated. Therefore, heavy-subtype surfactant was recovered from alveolar washes of 132-, 139-, and 148-day preterm lambs, 2- to 3-day-old newborn ventilated lambs, and adult sheep. The density of heavy-subtype surfactant and surfactant protein-A-to-saturated phosphatidylcholine ratios increased significantly with developmental age. In contrast, percent conversion from heavy to light surfactant forms was more rapid for surfactant from preterm animals than for surfactant from mature or adult animals. The function of the heavy-subtype surfactant was tested by treating ventilated 27-day gestational age preterm rabbits. The surfactant from the most immature animals was less effective at improving compliance or maintaining lung volumes on deflation than was surfactant from newborn or adult animals. These results demonstrate intrinsic and functional differences in surfactant from developing compared with mature sheep that correlated with the surfactant protein-A-content. The pattern of changes indicates that the preterm animal is at a disadvantage, because the surfactant is intrinsically abnormal relative to that of the adult.
- Published
- 1994
40. New technique to analyse global distributions of CO2 concentrations and fluxes from non-processed observational data
- Author
-
T. Maki, M. Ikegami, T. Fujita, T. Hirahara, K. Yamada, K. Mori, A. Takeuchi, Y. Tsutsumi, K. Suda, and T. J. Conway
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,13. Climate action ,14. Life underwater ,01 natural sciences ,0105 earth and related environmental sciences - Abstract
We have developed a new observational screening technique for inverse model. This technique was applied to our transport models with re-analysed meteorological data and the inverse model to estimate the global distribution of CO2 concentrations and fluxes. During the 1990s, we estimated a total CO2 uptake by the biosphere of 1.4–1.5 PgC yr-1 and a total CO2 uptake by the oceans of 1.7–1.8 PgC yr-1. The uncertainty of global CO2 flux estimation is about 0.3 PgC yr-1. We also obtained monthly surface CO2 concentrations in the marine boundary layer to precisions of 0.5–1.0 ppm. To utilize non-processed (statistical monthly mean) observational data in our analysis, we developed a quality control procedure for such observational data including a repetition of inversion. This technique is suitable for other inversion setups. Observational data by ships were placed into grids and used in our analysis to add to the available data from fixed stations. The estimated global distributions are updated and extended every year.DOI: 10.1111/j.1600-0889.2010.00488.x
- Published
- 2011
41. Three-dimensional variations of atmospheric CO2: aircraft measurements and multi-transport model simulations
- Author
-
Y. Niwa, P. K. Patra, Y. Sawa, T. Machida, H. Matsueda, D. Belikov, T. Maki, M. Ikegami, R. Imasu, S. Maksyutov, T. Oda, M. Satoh, and M. Takigawa
- Abstract
Numerical simulation and validation of three-dimensional structure of atmospheric carbon dioxide (CO2) is necessary for quantification of transport model uncertainty and its role on surface flux estimation by inverse modeling. Simulations of atmospheric CO2 were performed using four transport models and two sets of surface fluxes compared with an aircraft measurement dataset of Comprehensive Observation Network for Trace gases by AIrLiner (CONTRAIL), covering various latitudes, longitudes, and heights. Under this transport model intercomparison project, spatiotemporal variations of CO2 concentration for 2006–2007 were analyzed with a three-dimensional perspective. Results show that the models reasonably simulated vertical profiles and seasonal variations not only over northern latitude areas but also over the tropics and southern latitudes. From CONTRAIL measurements and model simulations, intrusion of northern CO2 in to the Southern Hemisphere, through the upper troposphere, was confirmed. Furthermore, models well simulated the vertical propagation of seasonal variation in the northern free-troposphere. However, significant model–observation discrepancies were found in Asian regions, which are attributable to uncertainty of the surface CO2 flux data. The models consistently underestimated the north-tropics mean gradient of CO2 both in the free-troposphere and marine boundary layer during boreal summer. This result suggests that the north-tropics contrast of annual mean net non-fossil CO2 flux should be greater than 2.7 Pg C yr−1 for 2007.
- Published
- 2011
42. Surfactant treatment effects on alveolar type II cell morphology in rabbit lungs
- Author
-
A. H. Jobe, A. M. Mulder, M. Ikegami, J. F. Lewis, and Kent E. Pinkerton
- Subjects
Pathology ,medicine.medical_specialty ,Physiology ,medicine.medical_treatment ,Lamellar granule ,Biology ,Pulmonary surfactant ,Physiology (medical) ,Internal medicine ,Parenchyma ,medicine ,Animals ,Respiratory system ,Lung ,Saline ,Cell Nucleus ,Lagomorpha ,Pulmonary Surfactants ,biology.organism_classification ,Pulmonary Alveoli ,Microscopy, Electron ,medicine.anatomical_structure ,Endocrinology ,Rabbits ,Perfusion - Abstract
The effects of exogenous surfactant administration on alveolar type II cells and the lung parenchyma were examined in adult rabbits. Natural surfactant was instilled into the left lobe of New Zealand White rabbits while the right lobe served as the control. Four hours post-instillation, the lungs were fixed by vascular perfusion. Surfactant instillation did not change alveolar type II cell size but was associated with a significant reduction in the volume fraction of lamellar bodies in type II cells (20.4% in control lobes compared with 11.9% in surfactant-treated lobes). The size distribution of lamellar body profiles was different in surfactant-treated lobes compared with control lobes, with a significant decrease in lamellar bodies > 0.8 microns in diameter and a twofold increase in lamellar bodies 0.2–0.4 microns in diameter. Composite body profile number was also increased by 87% (P < 0.05) after instillation of surfactant compared with control. Saline instillation decreased lamellar body volume fraction in type II cells but three times less than surfactant instillation. These observations are consistent with a strong stimulus for secretion of endogenous surfactant 4 h after surfactant instillation in normal adult rabbit lungs, whereas the increase in composite bodies is consistent with new lamellar body formation, probably from both de novo synthesized and exogenous natural rabbit surfactant. These observations confirm that the secretory and synthetic processes of alveolar type II cells are significantly affected by exogenous surfactant instillation.
- Published
- 1993
43. Contents Vol. 44, 2001
- Author
-
Chikara Miyamoto, Esteban Domingo, N. Sugimura, Fuat Kurbanov, Hideki Endo, Caron Pyne, Mayte Pérez-Olmeda, Ryuzo Ueda, Keiichi Saeki, Nodira Yuldasheva, Yan Zhou, Dildora Avazova, Tanja K. Tolle, F.M. Burlandy, Sylvia Nitsche, Sotaro Mushiake, Sung Wook Seo, Hitoshi Tajiri, Vincent Soriano, M.A. Rebello, Y. Onobori, Won-Ho Lee, Sigrun Broehl, Yuri Etani, Yoshitsugu Matsumoto, Heui-Soo Kim, Ruslan Ruzibakiev, M. Ikegami, Wolfram H. Gerlich, Yukiko Nasu, Atsutaka Kubosaki, Carmen Altisent, Takashi Onodera, Nicola Fiedler, Yasuhiro Furuichi, Michie Hashimoto, Kazuhiro Hara, Atsushi Sawada, Andreas Berting, Stephan Schaefer, Masashi Mizokami, T. Natsuaki, Minako Hijikata, Shunji Mishiro, Carlos Briones, Joo-Mi Yi, Tatyana Hegay, Dieter Glebe, Antonio Mas, Hwan-Mook Kim, Mariam Zalalieva, Lazis Tuichiev, Maria Seifer, Yasuhiko Ohta, Takuya Nishimura, Heike Naumann, Ralph Schuster, Tatsuya Tanaka, Hideaki Kato, Kosuke Kozaiwa, Bakhodir Achundjanov, and Suresh K. Tikoo
- Subjects
Infectious Diseases ,Virology - Published
- 2001
44. Molecular and crystal structure of methyl hepta-O-acetyl-α-laminarabioside
- Author
-
M Ikegami
- Subjects
Organic Chemistry ,General Medicine ,Biochemistry ,Analytical Chemistry - Published
- 1992
45. Electron motion on a curved interface
- Author
-
Yosuke Nagaoka and M. Ikegami
- Subjects
Physics ,Condensed matter physics ,Surfaces and Interfaces ,Electron ,Circular cone ,Condensed Matter Physics ,Curvature ,Electron motion ,Surfaces, Coatings and Films ,Magnetic field ,symbols.namesake ,Quantum mechanics ,Materials Chemistry ,symbols ,Hamiltonian (quantum mechanics) - Abstract
The effect of the bend of an interface to which electrons are confined is studied. It is shown that there appears an attractive potential due to the curvature in the two-dimensional effective Hamiltonian of an electron. The effect of an external magnetic field can be taken into account by simply replacing the momentum operators Pi, in the effective Hamiltonian with Pi + (ec)Ai, as far as the field is within the range of ordinary strength. Some examples of curved interfaces are studied. An interesting behaviour of electrons is found in the case of a circular cone, that is “fall” of electrons to the vertex.
- Published
- 1992
46. Effect of Thermal Cycling on the Martensitic Transformation in an Fe–24Mn–6Si Shape Memory Alloy
- Author
-
W. Nakagawara, Tadashi Maki, Yo Tomota, Kaneaki Tsuzaki, Yasuyoshi Kurokawa, and M. Ikegami
- Subjects
Materials science ,Metallurgy ,General Engineering ,Thermodynamics ,Temperature cycling ,Shape-memory alloy ,Solution treatment ,Microstructure ,law.invention ,Optical microscope ,Transmission electron microscopy ,law ,Martensite ,Diffusionless transformation - Abstract
The effect of γ⇄e cyclic transformation on the subsequent γ→e martensitic transformation has been studied in an Fe-24%Mn-6%Si shape memory alloy in order to obtain fundamental information on the role of Si in the shape memory effect. The γ→e martensitic transformation is markedly enhanced by thethermal cycling between 305 K (below M s ) and 573 K (above A f ), although the M s temperature slightly decreases. The amount of e martensite at 305 K is less than 30% after a solution treatment and increases to 40% after 10 thermal cycles
- Published
- 1992
47. Laser-driven proton acceleration and plasma diagnostics with J-KAREN laser
- Author
-
Akira Noda, Jinglong Ma, Toyoaki Kimura, Koichi Ogura, Yoshihisa Iwashita, Toshiki Tajima, S. Orimo, Tomohiro Motomura, Akifumi Yogo, S. Kondo, Yuji Oishi, Hiroyuki Daido, H. Sugiyama, Shuhei Kanazawa, M. Ikegami, Seong Ku Lee, Akito Sagisaka, J. Lee, Yoshiki Nakai, Hajime Okada, A. Akutsu, Alexander S. Pirozhkov, S. V. Bulanov, Manabu Tanoue, T. Zh. Esirkepov, Mamiko Nishiuchi, Il Woo Choi, Takuya Shimomura, T. Shirai, Michiyasu Mori, and Hiromitsu Kiriyama
- Subjects
Materials science ,business.industry ,Amplifier ,Saturable absorption ,Plasma ,Nanosecond ,Laser ,law.invention ,Acceleration ,Interferometry ,Optics ,law ,Physics::Accelerator Physics ,Plasma diagnostics ,business - Abstract
We describe results of experiments on laser-driven proton acceleration and corresponding laser-plasma diagnostics performed with the multi-10-TW J-KAREN laser. The laser consists of a high-pulse-energy oscillator, saturable absorber, stretcher, Optical Parametric Chirped Pulse Amplifier (OPCPA), two 4-pass Ti:Sapphire amplifiers, and compressor. The final amplifier is cryogenically cooled down to 100 K to avoid thermal lensing. The laser provides ~30 fs, ~ 1 J, high-contrast pulses with the nanosecond contrast better than 1010. The peak intensity is 1020 W/cm2 with the 3- 4 μm focal spot. Using few-μm tape and sub-μm ribbon targets we produced protons with the energies up to 4 MeV. The tape target and repetitive laser operation allowed achieving proton acceleration at 1 Hz. We found significant differences in stability and angular distribution of proton beam in high-contrast and normal-contrast modes. The plasma diagnostics included interferometry and measurement of the target reflectivity. The latter provides convenient diagnostics of the laser contrast in the ion acceleration, harmonics generation, and other laser - solid target interaction experiments.
- Published
- 2009
48. Laser driven proton beam for the applications: toward ultra-high intensity & short pulse proton beam
- Author
-
M. Nishiuchi, H. Daido, I. Daito, M. Ikegami, M. Mori, S. Orimo, K. Ogura, A. Sagisaka, A. Yogo, A. S. Pirozhkov, H. Sugiyama, H. Kiriyama, H. Okada, S. Kanazawa, S. Kondo, T. Shimomura, M. Tanoue, Y. Nakai, H. Sasao, D. Wakai, H. Sakaki, T. Hori, P. Bolton, I. W. Choi, J. H. Sung, J. Lee, Y. Oishi, T. Fujii, K. Nemoto, H. Souda, A. Noda, Y. Iseki, T. Yoshiyuki, Paul R. Bolton, Hiroyuki Daido, and Sergei V. Bulanov
- Subjects
Physics ,Laser ablation ,Proton ,business.industry ,Particle accelerator ,Laser ,Electromagnetic radiation ,law.invention ,Full width at half maximum ,Optics ,law ,Physics::Accelerator Physics ,Atomic physics ,business ,Quadrupole magnet ,Beam (structure) - Abstract
As a benchmark experiment to realize a novel and compact laser driven proton accelerator whose significant features are high number density in a short pulse width (∼ns), 2.4 MeV laser driven proton beam is stably focused at 1 Hz repetition rate by using a pair of permanent quadrupole magnets (PMQs) with large apertures whose diameters and field strengths are 3.5 cm and 55 T/m for the first and 2.3 cm and 60 T/m for the second magnets, respectively. The proton beam has been focused to a focal spot of 3×8 mm2 in horizontal and vertical direction (full width at half maximum) at 650∼mm from the source, which is well reproduced by the simulation. The further optimization of the focusing system will sure to pave a way to the novel proton accelerator with which we can investigate the physics appeared in the short time scale as well as that in a high energy density matter, oncology, astrophysics, and so on.
- Published
- 2009
49. Review on Recent High Intensity Physics Experiments Relevant to X-Ray and Quantum Beam Generation at JAEA
- Author
-
Y. C. Noh, Tae Jun Yu, Manabu Tanoue, Jae Koo Lee, Masayuki Suzuki, Motonobu Tampo, Y. Fukuda, H. Sasao, K. Nemoto, S. Kondo, Takuya Shimomura, Shunichi Kawanishi, Takuya Nayuki, Hiroyuki Daido, Koichi Ogura, H. Nishimura, J. H. Sung, Keiji Nagai, Akito Sagisaka, Tetsuya Kawachi, I. W. Choi, Y. Nakai, S. V. Bulanov, D. K. Ko, Akifumi Yogo, Alexander S. Pirozhkov, Nasr A. M. Hafz, Takashi Fujii, Masaharu Nishikino, D. Wakai, Y. Oishi, T. Esirkepov, H. Sakaki, Toshiki Tajima, P. R. Bolton, Hideo Nagatomo, S. Orimo, M. Ikegami, Izuru Daito, S. Kanazawa, T. M. Jeong, Mamiko Nishiuchi, Hiroyuki Okada, Chul Min Kim, T. A. Pikuz, Hiromitsu Kiriyama, M. Mori, and A. Y. Faenov
- Subjects
Physics ,business.industry ,Multiple quantum ,High intensity ,X-ray ,Laser ,law.invention ,Nuclear physics ,Optics ,law ,Laser power scaling ,business ,Quantum ,FOIL method ,Beam (structure) - Abstract
The authors describe firstly the lasers for high intensity physics experiments at JAEA including J-KAREN and JLITE-X lasers which can deliver 00TW and 0TW laser power, respectively. Secondly the authors describe demonstration of flying mirror technique which will become a new technique to make a coherent tunable x-ray source. Thirdly a femto-second laser driven incoherent soft x-ray source and its imaging applications for nano-structures are described. The th topic includes femto-second laser driven multiple quantum beam generation and its applications using a laser driven thin foil target.
- Published
- 2009
50. MeV quasi-mono-energetic proton beam created by a combination of a laser-plasma ion accelerator and synchronous rf cavity
- Author
-
M. Ikegami, S. Nakamura, Y. Iwashita, T. Shirai, H. Souda, Y. Tajima, M. Tanabe, H. Tongu, H. Itoh, H. Shintaku, A. Yamazaki, H. Daido, A. Yogo, S. Orimo, M. Mori, M. Nishiuchi, K. Ogura, A. Pirozhkov, J. Ma, H. Kiriyama, S. Kanazawa, A. Sagisaka, S. Kondo, Y. Yamamoto, T. Shimomura, M. Tanoue, Y. Nakai, A. Akutsu, S. V. Bulanov, T. Kimura, Y. Oishi, K. Nemoto, T. Tajima, A. Noda, and Sergei V. Bulanov
- Subjects
Physics ,Photon ,Laser ablation ,Proton ,law ,Electric field ,Physics::Accelerator Physics ,Particle accelerator ,Radio frequency ,Atomic physics ,Laser ,Beam (structure) ,law.invention - Abstract
MeV quasi‐mono‐energetic proton beam is produced by a combination of a synchronous radio frequency (rf) electric field and laser‐plasma ion acceleration. The experiment was carried out at the Kansai Photon Science Institute, JAEA, using the Ti:Sapphire laser system called J‐KAREN. The proton beam is emitted normal to the rear surface of the thin polyimide target of the thickness 7.5 μm irradiated at peak intensity of 4×1018 W/cm2. The energy spread is compressed from 100% to less than 11% at FWHM by the rf field. The focusing and defocusing effect of the transverse direction is also observed. These are also studied by a Monte Carlo simulation. The relation between the transverse focusing and the energy spectrum of the phase‐rotated beam is systematically shown by the simulation.
- Published
- 2008
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.