322 results on '"T, Sonobe"'
Search Results
2. Orbital-anisotropic electronic structure in the nonmagnetic state of BaFe2(As1−x P x )2 superconductors
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T. Sonobe, T. Shimojima, A. Nakamura, M. Nakajima, S. Uchida, K. Kihou, C. H. Lee, A. Iyo, H. Eisaki, K. Ohgushi, and K. Ishizaka
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Medicine ,Science - Abstract
Abstract High-temperature superconductivity in iron-pnictides/chalcogenides arises in balance with several electronic and lattice instabilities. Beside the antiferromagnetic order, the orbital anisotropy between Fe 3d xz and 3d yz occurs near the orthorhombic structural transition in several parent compounds. However, the extent of the survival of orbital anisotropy against the ion-substitution remains to be established. Here we report the composition (x) and temperature (T) dependences of the orbital anisotropy in the electronic structure of a BaFe2(As1−x P x )2 system by using angle-resolved photoemission spectroscopy. In the low-x regime, the orbital anisotropy starts to evolve on cooling from high temperatures above both antiferromagnetic and orthorhombic transitions. By increasing x, it is gradually suppressed and survives in the optimally doped regime. We find that the in-plane orbital anisotropy persists in a large area of the nonmagnetic phase, including the superconducting dome. These results suggest that the rotational symmetry-broken electronic state acts as the stage for superconductivity in BaFe2(As1−x P x )2.
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- 2018
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3. Cluster-Based Industrial Development: KAIZEN Management for MSE Growth in Developing Countries
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T. Sonobe, K. Otsuka
- Published
- 2014
4. Cluster-Based Industrial Development: A Comparative Study of Asia and Africa
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T. Sonobe, K. Otsuka
- Published
- 2010
5. Back bombardment for dispenser and lanthanum hexaboride cathodes
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Mahmoud Bakr, R. Kinjo, Y. W. Choi, M. Omer, K. Yoshida, S. Ueda, M. Takasaki, K. Ishida, N. Kimura, T. Sonobe, T. Kii, K. Masuda, H. Ohgaki, and H. Zen
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Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
The back bombardment (BB) effect limits wide usage of thermionic rf guns. The BB effect induces not only ramping-up of a cathode’s temperature and beam current, but also degradation of cavity voltage and beam energy during a macropulse. This paper presents a comparison of the BB effect for the case of dispenser tungsten-base (DC) and lanthanum hexaboride (LaB_{6}) thermionic rf gun cathodes. For each, particle simulation codes are used to simulate the BB effect and electron beam dynamics in a thermionic rf gun cathode. A semiempirical equation is also used to investigate the stopping range and deposited heat power of BB electrons in the cathode material. A numerical simulation method is used to calculate the change of the cathode temperature and current density during a single macropulse. This is done by solving two differential equations for the rf gun cavity equivalent circuit and one-dimensional thermal diffusion equation. High electron emission and small beam size are required for generation of a high-brightness electron beam, and so in this work the emission properties of the cathode are taken into account. Simulations of the BB effect show that, for a pulse of 6 μs duration, the DC cathode experiences a large change in the temperature compared with LaB_{6}, and a change in current density 6 times higher. Validation of the simulation results is performed using experimental data for beam current beyond the gun exit. The experimental data is well reproduced using the simulation method.
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- 2011
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6. Orbital-anisotropic electronic structure in the nonmagnetic state of BaFe2(As1−xPx)2 superconductors
- Author
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S. Uchida, Makoto Nakajima, Akira Iyo, T. Sonobe, Hiroshi Eisaki, Kenya Ohgushi, K. Kihou, Kyoko Ishizaka, C. H. Lee, A. Nakamura, and Takahiro Shimojima
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Superconductivity ,Multidisciplinary ,Materials science ,Condensed matter physics ,Photoemission spectroscopy ,Science ,Doping ,02 engineering and technology ,Electronic structure ,021001 nanoscience & nanotechnology ,01 natural sciences ,Article ,Lattice (order) ,Condensed Matter::Superconductivity ,0103 physical sciences ,Antiferromagnetism ,Medicine ,Orthorhombic crystal system ,Condensed Matter::Strongly Correlated Electrons ,010306 general physics ,0210 nano-technology ,Anisotropy - Abstract
High-temperature superconductivity in iron-pnictides/chalcogenides arises in balance with several electronic and lattice instabilities. Beside the antiferromagnetic order, the orbital anisotropy between Fe 3d xz and 3d yz occurs near the orthorhombic structural transition in several parent compounds. However, the extent of the survival of orbital anisotropy against the ion-substitution remains to be established. Here we report the composition (x) and temperature (T) dependences of the orbital anisotropy in the electronic structure of a BaFe2(As1−xP x )2 system by using angle-resolved photoemission spectroscopy. In the low-x regime, the orbital anisotropy starts to evolve on cooling from high temperatures above both antiferromagnetic and orthorhombic transitions. By increasing x, it is gradually suppressed and survives in the optimally doped regime. We find that the in-plane orbital anisotropy persists in a large area of the nonmagnetic phase, including the superconducting dome. These results suggest that the rotational symmetry-broken electronic state acts as the stage for superconductivity in BaFe2(As1−xP x )2.
- Published
- 2018
7. Multiple-pseudogap phases in the hydrogen-doped LaFeAsO system
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Satoshi Yoshida, Takahiro Shimojima, T. Sonobe, A. Nakamura, Hideo Hosono, Walid Malaeb, Kyoko Ishizaka, S. Matsuishi, S. Iimura, and Shik Shin
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Physics ,Superconductivity ,Condensed Matter - Materials Science ,Condensed matter physics ,Photoemission spectroscopy ,Condensed Matter - Superconductivity ,Fermi level ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,02 engineering and technology ,Electronic structure ,021001 nanoscience & nanotechnology ,01 natural sciences ,Superconductivity (cond-mat.supr-con) ,symbols.namesake ,Condensed Matter::Superconductivity ,0103 physical sciences ,Density of states ,symbols ,Antiferromagnetism ,Condensed Matter::Strongly Correlated Electrons ,010306 general physics ,0210 nano-technology ,Pseudogap ,Phase diagram - Abstract
The low energy electronic structure of LaFeAsO1-xHx (0.0 < x < 0.60), the system which exhibits two superconducting domes in its phase diagram, is investigated by utilizing the laser photoemission spectroscopy. From the precise temperature-dependent measurement of the spectra near the Fermi level, we find the suppression of the density of states with cooling, namely the pseudogap formation, for all doping range. The pseudogap in the low x range (i.e. the first superconducting dome regime) gets suppressed with increasing x, more or less similarly to the previous results in F-doped LaFeAsO system. On the other hand, the pseudogap behavior in the second superconducting dome regime at high-x becomes stronger with increasing the H-doping level. The systematic doping dependence shows that the pseudogap is enhanced toward the both ends of the phase diagram where the different types of antiferromagnetic order exist., 8 pages, 6 figures
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- 2017
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8. Evaluation of wall motion abnormality by comparing values of cardiac output obtained by M-mode and Doppler echocardiography: Parameter revealing wall motion abnormality in stress echocardiography
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Hiroaki Okawai, Shin-ichi Nitta, Hiroyuki Nakajima, Keiko Nitta, Masashi Fujita, T. Sonobe, Kazuhiko Takahashi, and Yoshiaki Katahira
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Cardiac function curve ,Cardiac output ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,General Medicine ,Stroke volume ,Doppler echocardiography ,medicine.disease ,Dipyridamole ,Internal medicine ,Stress Echocardiography ,Cardiology ,Medicine ,Radiology, Nuclear Medicine and imaging ,Dobutamine ,Radiology ,business ,Stroke ,medicine.drug - Abstract
Dobutamine and dipyridamole stress echocardiographies are both well able to detect myocardial ischemia resulting from coronary diseases by recognizing the regional wall motion abnormality (WMA). Here we report a method for describing WMA in detail. In pharmacological stress echocardiography, because of difficulties in recognizing the two-dimensional pattern, accuracy sometimes depends upon the skill of the operator. Two stroke volumes obtained using the M-mode and Doppler methods were examined to detect abnormal regional cardiac function by the dipyridamole stress test. Stroke volume obtained by the M-modereflects regional cardiac function and that estimated from the outflow using the Doppler methodreflects total cardiac function. These two stroke volumes were compared in normal subjects and patients with coronary-diseases. The results indicated consistent discrepancies between these two stroke volume in the ischemic hearts as a results of coronary stenosis, whereas changes in stroke volumes in the normal subjects showed the same tendency. This method of combining information about the regional and total functions is thus useful in examining the WMA and regional cardiac function, although it can not be applied to subjects whose stroke volume does not increase under stress.
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- 2016
9. Comparison of the Heating Properties of LaB6 and CeB6 Due to the Back Comparison of the Heating Properties of LaB6 and CeB6 Due to the Back
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Mahmoud Bakr, R. Kinjo, Y. W. Choi, M. Omer, K. Yoshida, S. Ueda, M. Takasaki, K. Ishida, N. Kimura, H. Zen, T. Sonobe, T. Kii, K. Masuda, and H. Ohgaki
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Materials science ,business.industry ,General Physics and Astronomy ,Optoelectronics ,Thermionic emission ,business ,Electron gun - Published
- 2011
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10. Giant Rashba-type spin splitting in bulk BiTeI
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Takahiro Shimojima, Hirokazu Miyahara, Koji Miyamoto, Masaki Taniguchi, Shik Shin, Yoshio Kaneko, Taichi Okuda, Ryotaro Arita, Yoshinori Onose, M. Sakano, Yoshinori Tokura, K. Koizumi, T. Sonobe, H. Murakawa, Akio Kimura, Youichi Murakami, Mohammad Saeed Bahramy, Reiji Kumai, Kensuke Kobayashi, Kyoko Ishizaka, Naoto Nagaosa, and Hirofumi Namatame
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Physics ,Spin pumping ,Condensed matter physics ,Spin polarization ,Spintronics ,Condensed Matter::Other ,Mechanical Engineering ,Spin engineering ,General Chemistry ,Spin–orbit interaction ,Zero field splitting ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Condensed Matter Physics ,Mechanics of Materials ,Spinplasmonics ,Spin Hall effect ,Condensed Matter::Strongly Correlated Electrons ,General Materials Science - Abstract
There has been increasing interest in phenomena emerging from relativistic electrons in a solid, which have a potential impact on spintronics and magnetoelectrics. One example is the Rashba effect, which lifts the electron-spin degeneracy as a consequence of spin-orbit interaction under broken inversion symmetry. A high-energy-scale Rashba spin splitting is highly desirable for enhancing the coupling between electron spins and electricity relevant for spintronic functions. Here we describe the finding of a huge spin-orbit interaction effect in a polar semiconductor composed of heavy elements, BiTeI, where the bulk carriers are ruled by large Rashba-like spin splitting. The band splitting and its spin polarization obtained by spin- and angle-resolved photoemission spectroscopy are well in accord with relativistic first-principles calculations, confirming that the spin splitting is indeed derived from bulk atomic configurations. Together with the feasibility of carrier-doping control, the giant-Rashba semiconductor BiTeI possesses excellent potential for application to various spin-dependent electronic functions.
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- 2011
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11. Momentum-dependent sign inversion of orbital order in superconducting FeSe
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Takahiro Shimojima, Hiroshi Kontani, Youichi Yamakawa, M. Sakano, T. Sonobe, A. Nakamura, Makoto Kuwata-Gonokami, Ryo Kobayashi, J. Omachi, Yuji Matsuda, Shigeru Kasahara, Kosuke Yoshioka, Takasada Shibauchi, Tatsuya Watashige, H. Tsuji, Yasuhiro Suzuki, and Kyoko Ishizaka
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Physics ,Superconductivity ,Atomic orbital ,Condensed matter physics ,Photoemission spectroscopy ,Condensed Matter::Superconductivity ,Structural transition ,Orthorhombic crystal system ,Electronic structure ,Condensed Matter Physics ,Polarization (waves) ,Electronic, Optical and Magnetic Materials ,Fermi Gamma-ray Space Telescope - Abstract
We investigate the electronic reconstruction across the tetragonal-orthorhombic structural transition in FeSe by employing polarization-dependent angle-resolved photoemission spectroscopy on detwinned single crystals. Across the structural transition, the electronic structures around the $\mathrm{\ensuremath{\Gamma}}$ and $M$ points are modified from fourfold to twofold symmetry due to the lifting of degeneracy in ${d}_{xz}/{d}_{yz}$ orbitals. The ${d}_{xz}$ band shifts upward at the $\mathrm{\ensuremath{\Gamma}}$ point, while it moves downward at the $M$ point, suggesting that the electronic structure of orthorhombic FeSe is characterized by a momentum-dependent sign-changing orbital polarization. Due to this sign-changing orbital order, the elongated directions of the elliptical Fermi surfaces at the $\mathrm{\ensuremath{\Gamma}}$ and $M$ points are rotated by 90\ifmmode^\circ\else\textdegree\fi{} with respect to each other, which makes the nesting condition between these FSs imperfect. The present result, supported by calculations, indicates the possible suppression of the spin-fluctuation mediated superconductivity in the orthorhombic FeSe, as compared to the orbital-ordered state without sign change.
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- 2015
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12. Oral Presentations—Abstracts
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M. Bartsch, D. K. F. Meijer, G. L. Scherphof, J. A. A. M. Kamps, S. Erdoğan, A. Y. Özer, B. Caner, H. Bilgili, L. M. Ickenstein, K. Edwards, G. Karlsson, L. D. Mayer, Crispin G. S. Eley, Ning Hu, Gerard M. Jensen, K. Kawahara, A. Sekiguchi, E. Kiyoki, K. Morimoto, O. C. Boerman, M. Miyajima, J. Kimura, G. A. Koning, H. W. M. Morselt, Josbert M. Metselaar, Marca H. M. Wauben, Otto C. Boerman, Peter L. van Lent, Gert Storm, F. Pastorino, C. Brignole, D. Marimpietri, E. H. Moase, T. M. Allen, M. Ponzoni, K. Romøren, B. J. Thu, Ø Evensen, S. Rossi, S. Ristori, G. Martini, R. M. Schiffelers, G. Molema, T. L. M. ten Hagen, A. P. C. A. Janssen, R. G. Ebben, A. J. Schraa, R. J. Kok, G. Koning, G. Storm, S. I. Simões, C. M. Marques, M. E. Cruz, G. Cevc, M. B. Martins, D. Summers, D. Ruff, R. W. Smalling, D. Cardoza, D. Dottavio, D. Lasic, J. Szebeni, L. Baranyi, S. Savay, J. Milosevits, R. Bunger, P. Laverman, J. M. Metselaar, A. Chanan-Khan, L. Liebes, F. M. Muggia, R. Cohen, Y. Barenholz, C. R. Alving, S. Hoving, A. L. B. Seynhaeve, S. T. van Tiel, A. M. M. Eggermont, K. Tokutomi, Y. Sadzuka, A. Igarashi, H. Konno, and T. Sonobe
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Liposome ,Materials science ,Antisense oligodeoxynucleotides ,Albumin ,Cationic polymerization ,Pharmaceutical Science ,Molecular biology ,body regions ,chemistry.chemical_compound ,chemistry ,Covalent bond ,In vivo ,Mole ,Ethylene glycol - Abstract
Targeted Delivery of Antisense Oligodeoxynucleotides In Vivo by Means of Coated Cationic LipoplexesEarlier we reported on the massive uptake of liposomes surface-modified with negatively charged aconitylated albumin (Aco-HSA) by liver endothelial cells (EC) in vivo. In the present work we apply this principle for in vivo delivery of antisense oligodeoxynucleotides (ODN) to these cells by means of coated cationic lipoplexes (CCL) (). CCL were prepared by complexing ODN with the cationic lipid DOTAP and subsequent coating of the complex by neutral lipids including a lipid-anchored poly(ethylene glycol). Aco-HSA was covalently coupled.The Aco-HSA-CCLs were 160 nm in size, contained 1.03 ± 0.35 nmol ODN and 54 ± 18 µg Aco-HSA per µ mol total lipid. The Aco-HSA-CCLs were rapidly eliminated from plasma, 60% of the injected dose being recovered in the liver after 30 m. Within the liver, the EC accounted for two thirds of total liver uptake. Non-targeted CCLs were eliminated very slowly: after 30 m >90% of the pa...
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- 2003
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13. Lifting ofxz/yzorbital degeneracy at the structural transition in detwinned FeSe
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A. Nakamura, Christoph Meingast, J. Omachi, Makoto Kuwata-Gonokami, Kanta Ono, Takahiro Shimojima, Hilbert von Löhneysen, Yasuhiro Suzuki, Frédéric Hardy, Hiroshi Kumigashira, T. Sonobe, T. Wolf, Kyoko Ishizaka, Kosuke Yoshioka, M. Sakano, Anna E. Böhmer, and Hiroaki Ikeda
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Superconductivity ,Physics ,Strongly Correlated Electrons (cond-mat.str-el) ,Condensed matter physics ,Photoemission spectroscopy ,Condensed Matter - Superconductivity ,Center (category theory) ,FOS: Physical sciences ,Order (ring theory) ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Superconductivity (cond-mat.supr-con) ,Brillouin zone ,Condensed Matter - Strongly Correlated Electrons ,Condensed Matter::Materials Science ,Condensed Matter::Superconductivity ,Antiferromagnetism ,Condensed Matter::Strongly Correlated Electrons ,Orthorhombic crystal system ,Energy (signal processing) - Abstract
We study superconducting FeSe (Tc = 9 K) exhibiting the tetragonal-orthorhombic structural transition (Ts = 90 K) without any antiferromagnetic ordering, by utilizing angle-resolved photoemission spectroscopy. In the detwinned orthorhombic state, the energy position of the dyz orbital band at the Brillouin zone corner is 50 meV higher than that of dxz, indicating the orbital order similar to NaFeAs and BaFe2As2 families. Evidence of orbital order also appears in the hole bands at the Brillouin zone center. Precisely measured temperature dependence using strain-free samples shows that the onset of the orbital ordering (To) occurs very close to Ts, thus suggesting that the electronic nematicity above Ts is considerably weaker in FeSe compared to BaFe2As2 family., Comment: 6 pages, 4 figures
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- 2014
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14. Sign of wall motion abnormality observed in wall thickness change, excursion, and stroke volume obtained by M-mode: The parameter revealing wall motion abnormality in stress echocardiography (2)
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Keiko Nitta, Liqing Xu, Kazuhiko Takahashi, Masashi Fujita, Hiroyuki Nakajima, Yoshiaki Katahira, Hiroaki Okawai, Shin-ichi Nitta, and T. Sonobe
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Ultrasound ,Excursion ,General Medicine ,Stroke volume ,medicine.disease ,Scintigraphy ,Coronary artery disease ,Dipyridamole ,medicine.anatomical_structure ,Internal medicine ,medicine ,Cardiology ,Stress Echocardiography ,Radiology, Nuclear Medicine and imaging ,Interventricular septum ,business ,medicine.drug - Abstract
To improve the evaluation of regional wall motion abnormalities (WMA) during stress echocardiography, the parameters of the wall thickness change, excursion and stroke volume, with time-dependent changes in two regional portions of the interventricular septum and the posterior wall evaluated with M-mode ultrasonography are proposed. Response to the dipyridamole stress test was studied in two normal subjects and eight subjects with coronary disease. Regional wall motion and stroke volume were measured, and the results were compared with results obtained with coronary angiography, 2-D echography, and radioisotope scintigraphy. In normal subjects, these parameters showed only monotonous change with the passage of time. In patients with coronary artery disease, however, discrepancy in wall thickness and excursion between the interventricular septum and the posterior wall appeared within 1 to 3 minutes after the start of the test. Thus, despite the limitation of the examined area imposed by use of M-mode, the motion of the interventricular septum and the posterior wall described the details of WMA and an ischemic state.
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- 2001
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15. ASCAObservation of the Distant Cluster of Galaxies Cl 0016+16 and Implication forH0
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Hideyo Kunieda, R. F. Mushotzky, Yuzuru Tawara, T. Sonobe, Yasuyuki T. Tanaka, K. Yamashita, and Akihiro Furuzawa
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Physics ,Astrophysics::High Energy Astrophysical Phenomena ,Astronomy ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Plasma ,Radius ,Astrophysics ,Galaxy ,Redshift ,law.invention ,Radio telescope ,Telescope ,symbols.namesake ,Space and Planetary Science ,law ,symbols ,Galaxy cluster ,Hubble's law - Abstract
We report the 0.5-10 keV X-ray image and spectrum of Cl 0016+16, which, at a redshift of 0.541, is one of the most distant clusters of galaxies observed with ASCA. The ASCA X-ray image is well represented by an isothermal β model. The best-fit parameters for the core radius (θc) and β are 06 and 0.7, respectively. However, because of ASCA's moderate spatial resolution, these two parameters are strongly correlated. The observed spectrum within a 6' radius is well fitted by a thin thermal emission model with a plasma temperature of 8.0 ± 1.0 keV. The Sunyaev-Zeldovich (SZ) effect in Cl 0016+16 has been observed by Carlstrom et al. using an interferometer and by Birkinshaw et al. using a single-dish radio telescope. Combining the SZ microwave decrement with the plasma density and temperature profiles derived from our X-ray observation, we obtained a value of the Hubble constant of 47 ± 14 km s-1 Mpc-1 with the profile parameters obtained by interferometric data, and 52 ± 20 km s-1 Mpc-1 with our best-fit shape parameters and single-dish telescope data.
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- 1998
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16. Pseudogap formation above the superconducting dome in iron pnictides
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Toshimitsu Ito, Shigeru Kasahara, Hiroshi Kumigashira, Kenya Ohgushi, Kyoko Ishizaka, Hiroaki Anzai, Takasada Shibauchi, S. Ideta, K. Shinada, Shik Shin, Hiroshi Eisaki, S. Uchida, Teppei Yoshida, Hirofumi Namatame, Takahito Terashima, T. Sonobe, Masamichi Nakajima, Ashish Chainani, Masashi Arita, Hiroaki Ikeda, Akihiro Ino, Kanta Ono, Yuji Matsuda, Akira Iyo, K. Kihou, Walid Malaeb, Atsushi Fujimori, Masaki Taniguchi, Takahiro Shimojima, Yasuhide Tomioka, C. H. Lee, and Y. Nakashima
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Condensed Matter::Quantum Gases ,Physics ,Superconductivity ,Condensed matter physics ,Photoemission spectroscopy ,Condensed Matter - Superconductivity ,Transition temperature ,FOS: Physical sciences ,Electronic structure ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Superconductivity (cond-mat.supr-con) ,Atomic orbital ,Condensed Matter::Superconductivity ,Condensed Matter::Strongly Correlated Electrons ,Cuprate ,Pseudogap ,Energy (signal processing) - Abstract
The nature of the pseudogap in high transition temperature (high-Tc) superconducting cuprates has been a major issue in condensed matter physics. It is still unclear whether the high-Tc superconductivity can be universally associated with the pseudogap formation. Here we provide direct evidence of the existence of the pseudogap phase via angle-resolved photoemission spectroscopy in another family of high-Tc superconductor, iron-pnictides. Our results reveal a composition dependent pseudogap formation in the multi-band electronic structure of BaFe2(As1-xPx)2. The pseudogap develops well above the magnetostructural transition for low x, persists above the nonmagnetic superconducting dome for optimal x and is destroyed for x ~ 0.6, thus showing a notable similarity with cuprates. In addition, the pseudogap formation is accompanied by inequivalent energy shifts in xz/yz orbitals of iron atoms, indicative of a peculiar iron orbital ordering which breaks the four-fold rotational symmetry., Comment: 14 pages, 10 figures
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- 2014
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17. Anteroventral pre-optic neurones, control of breathing and H₂S: physiology or toxicology?
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P, Haouzi, T, Sonobe, and B, Chenuel
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Male ,Animals ,Hyperventilation ,Hydrogen Sulfide ,Hypoxia - Published
- 2013
18. Cluster-Based Industrial Development : A Comparative Study of Asia and Africa
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T. Sonobe, K. Otsuka, T. Sonobe, and K. Otsuka
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- Industrial concentration--Africa--Case studies, Industrial concentration--Asia--Case studies, Industrialization--Asia--Case studies, Industrialization--Africa--Case studies
- Abstract
This book examines how to promote industrial development in low-income countries. It considers the role of traders in the evolution of a cluster, the role of managerial human capital, the effect of the'China shock', and the role of industrial policies focused on international knowledge transfer in supporting the upgrading of clusters.
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- 2011
19. Chaotic Behavior of Hemodynamics with Ventricular Assist System
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T. Yambe, S. Nanka, T. Sonobe, S. Naganuma, S. Kobayashi, H. Akiho, Y. Kakinuma, M. Mitsuoka, S. Chiba, N. Ohsawa, Y. Haga, K. Idutsu, S. Nitta, T. Fukuju, M. Miura, N. Uchida, N. Sato, K. Tabayashi, A. Tanaka, N. Yoshizumi, K. Abe, M. Takayasu, H. Takayasu, and M. Yoshizawa
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Lyapunov function ,Phase portrait ,Computer science ,Quantitative Biology::Tissues and Organs ,Physics::Medical Physics ,Biomedical Engineering ,Medicine (miscellaneous) ,Bioengineering ,General Medicine ,Lyapunov exponent ,01 natural sciences ,010305 fluids & plasmas ,Biomaterials ,Nonlinear system ,symbols.namesake ,Complex dynamics ,Control theory ,Phase space ,0103 physical sciences ,Attractor ,symbols ,State space ,010301 acoustics - Abstract
In order to analyze hemodynamic parameters during left ventricular assistance as an entity and not as decomposed parts, non-linear mathematical techniques were utilized. Pneumatically actuated ventricular assist systems (VAS) were implanted as left heart bypasses in acute animal experiments, using healthy adult mongrel dogs. By the use of the non-linear mathematical technique, the arterial blood pressure waveform (AP) was embedded into the four-dimensional phase space and projected into the three-dimensional phase space. The Lyapunov numerical method was used as an adjunct to the graphical analysis of the state space. The phase portrait of the attractor showed a complex structure; a three dimensional solid torus with a screw type structure as a part, suggesting deterministic chaos in the AP without left ventricular assistance. Positive lyapunov exponents confirmed the existence of chaos. During counterpulsation mode left ventricular assistance, the phase portrait of the attractor showed a more complex structure, and positive Lyapunov exponents suggested a greater dimensional deterministic chaos. However, non-structured patterns were seen in the phase space during internal mode VAS driving, suggesting the possibility of dissipative dynamics in the four dimensional phase space. These results suggest that the cardiovascular system with counterpulsation mode VAS driving is in a homeochaotic state, which is thought to be a flexible and intelligent control system. And there is greater dimensional complex dynamics in the circulatory regulatory system with VAD during internal mode assistance.
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- 1995
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20. Three-dimensional bulk band dispersion in polar BiTeI with giant Rashba-type spin splitting
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Naoto Nagaosa, Mohammad Saeed Bahramy, Jun Miyawaki, M. Sakano, Kyoko Ishizaka, Ashish Chainani, H. Murakawa, T. Sonobe, Y. Tokura, Takahiro Shimojima, Yoshio Kaneko, Masaki Oura, Y. Takata, Ryotaro Arita, and Shik Shin
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Physics ,Condensed Matter - Materials Science ,Condensed matter physics ,business.industry ,Photoemission spectroscopy ,media_common.quotation_subject ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,Crystal structure ,Type (model theory) ,Condensed Matter Physics ,Asymmetry ,Electronic, Optical and Magnetic Materials ,Semiconductor ,Polar ,Condensed Matter::Strongly Correlated Electrons ,business ,Electronic band structure ,media_common ,Spin-½ - Abstract
In layered polar semiconductor BiTeI, giant Rashba-type spin-split band dispersions show up due to the crystal structure asymmetry and the strong spin-orbit interaction. Here we investigate the 3-dimensional (3D) bulk band structures of BiTeI using the bulk-sensitive $h\nu$-dependent soft x-ray angle resolved photoemission spectroscopy (SX-ARPES). The obtained band structure is shown to be well reproducible by the first-principles calculations, with huge spin splittings of ${\sim}300$ meV at the conduction-band-minimum and valence-band-maximum located in the $k_z=\pi/c$ plane. It provides the first direct experimental evidence of the 3D Rashba-type spin splitting in a bulk compound., Comment: 9 pages, 4 figures
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- 2012
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21. FEL Beamline for Wide Tunable Range and Beam Sharing System at Kyoto University
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Mahmoud Bakr, K. Yoshida, K. Higashimura, S. Ueda, R. Kinjo, H. Zen, T. Sonobe, T. Kii, K. Masuda, H. Ohgaki, Adriana Predoi-Cross, and Brant E. Billinghurst
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Physics ,Range (particle radiation) ,business.industry ,Electrical engineering ,Free-electron laser ,Bremsstrahlung ,Particle accelerator ,Laser ,law.invention ,Renewable energy ,Optics ,Beamline ,law ,business ,Beam (structure) - Abstract
A mid‐infrared free electron laser (MIR‐FEL) facility (KU‐FEL: Kyoto University Free Electron Laser) has been constructed for developing energy materials in Institute of Advanced Energy (IAE), Kyoto University. The tunable range of KU‐FEL was estimated as 5–13.2 μm by numerical calculation to design the MIR‐FEL transport line for application purposes. Aiming to increase the number of FEL users with different desires we decided to develop an FEL beam sharing system that is useful for multi‐utilization at different end‐stations. The transport line and the beam sharing system has been designed and constructed to the user stations. Applications of the MIR‐FEL in the renewable energy research at Kyoto University will start as well.
- Published
- 2010
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22. Investigation of the Effects of MIR-FELIrradiation on the Photoluminescence of Titanium Dioxides
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T. Sonobe, M. Bakr, K. Yoshida, K. Higashimura, R. Kinjo, K. Hachiya, T. Kii, K. Masuda, H. Ohgaki, Adriana Predoi-Cross, and Brant E. Billinghurst
- Subjects
Photoluminescence ,Materials science ,business.industry ,Free-electron laser ,chemistry.chemical_element ,Laser ,law.invention ,Amorphous solid ,symbols.namesake ,Optics ,chemistry ,law ,symbols ,Optoelectronics ,business ,Raman spectroscopy ,Luminescence ,Raman scattering ,Titanium - Abstract
A mid‐infrared free electron laser (MIR‐FEL: 5 μm–20 μm) facility (KU‐FEL: Kyoto University Free Electron Laser) has been constructed in Institute of Advanced Energy Kyoto University, and first laser saturation at 13.2 μm was achieved in May 2008. Currently, we have started to develop the application of MIR‐FEL in the field of energy and material science. This study aimed at investigating the feasibility for the development of new evaluation technique of electron‐phonon interaction in metal oxides by MIR‐FEL. A preliminary result of electrical and optical properties of titanium dioxides was presented.
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- 2010
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- View/download PDF
23. Mayer Waves in Dogs with Total Artificial Heart
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T. Yambe, S. Nitta, Y. Katahira, T. Sonobe, S. Naganuma, Y. Kakinuma, S. Kobayashi, M. Tanaka, M. Miura, N. Sato, H. Mohri, M. Yoshizawa, K. Izumi, and H. Takeda
- Subjects
medicine.medical_specialty ,Arterial pressure waveform ,business.industry ,030232 urology & nephrology ,Biomedical Engineering ,Medicine (miscellaneous) ,Maximum entropy method ,Hemodynamics ,Bioengineering ,General Medicine ,030204 cardiovascular system & hematology ,law.invention ,Biomaterials ,03 medical and health sciences ,Mayer waves ,Autonomic nervous system ,0302 clinical medicine ,law ,Artificial heart ,Internal medicine ,Respiration ,Cardiology ,medicine ,Respiratory system ,business - Abstract
To assess the effect of a total artificial heart (TAH) on the autonomic nervous system a power spectral analysis of the hemodynamics in a TAH animal was done by the maximum entropy method. Two pneumatically driven sac-type ventricular assist devices were implanted as total biventricular bypass (BVB) in adult mongrel dogs to compare the differences between natural heart and TAH. Once the BVB was pumping, the natural heart was electrically fibrillated to constitute the BVB-type TAH model. In the arterial pressure waveform in animals with TAH, respiratory waves were not changed (97.7±24.6%) though Mayer waves were significantly decreased (47.5 ± 22.6%) compared with the animal with a natural heart. These results suggest that prosthetic hemodynamics in the TAH animal affect fluctuations in the cardiovascular system.
- Published
- 1992
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- View/download PDF
24. Estimation of the following Cardiac Output Using Sympathetic Tone and Hemodynamics for the Control of a Total Artificial Heart
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T. Yambe, S. Nitta, Y. Katahira, T. Sonobe, S. Naganuma, H. Akiho, Y. Kakinuma, K. Izutzu, Y. Kikuchi, T. Naganuma, S. Kobayashi, H. Matsuzawa, M. Tanaka, M. Miura, N. Sato, T. Fukuju, H. Mohri, M. Yoshizawa, and H. Takeda
- Subjects
Cardiac function curve ,medicine.medical_specialty ,Cardiac output ,030232 urology & nephrology ,Biomedical Engineering ,Medicine (miscellaneous) ,Hemodynamics ,Bioengineering ,030204 cardiovascular system & hematology ,law.invention ,Biomaterials ,03 medical and health sciences ,0302 clinical medicine ,Afterload ,law ,Internal medicine ,Artificial heart ,medicine ,Sympathetic tone ,business.industry ,Mean Aortic Pressure ,General Medicine ,Preload ,Anesthesia ,cardiovascular system ,Cardiology ,business - Abstract
A sympathetic neurogram is potentially useful for the development of a real time total artificial heart (TAH) control system. We used sympathetic tone and hemodynamic derivatives to estimate the following cardiac output in acute animal experiments using adult mongrel dogs. Moving averages of the mean left atrial pressure and mean aortic pressure were used as parameters of the preload and afterload, respectively. Renal sympathetic nerve activity (RSNA) was employed as a parameter of sympathetic tone. Equations for the following cardiac output were calculated using multiple linear regression analysis of the time series data. A significant correlation was observed between the estimated and following measured cardiac output. These results suggest the potential usefulness of the sympathetic neurogram for the real time TAH automatic control system.
- Published
- 1992
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- View/download PDF
25. Cardiac-Related Sympathetic Nerve Activity during Circulation with Only the Left Ventricular Assist Device
- Author
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Tohru Naganuma, Yoshito Kakinuma, Makoto Yoshizawa, Tomoyuki Yambe, H. Takeda, Hiroyuki Hayashi, Shigeki Chiba, Naoshi Sato, Shigeru Naganuma, T. Sonobe, Yoshiaki Katahira, Makoto Miura, K. Izutsu, Masaru Tanaka, Hitoshi Mohri, Shigeo Sugawara, Kikuchi Y, Hiroshi Akiho, and Shin-ichi Nitta
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,030232 urology & nephrology ,Biomedical Engineering ,Medicine (miscellaneous) ,Bioengineering ,030204 cardiovascular system & hematology ,law.invention ,Biomaterials ,03 medical and health sciences ,0302 clinical medicine ,Rhythm ,law ,Artificial heart ,medicine.artery ,Internal medicine ,medicine ,Heart transplantation ,business.industry ,General Medicine ,equipment and supplies ,medicine.disease ,Autonomic nervous system ,Ventricular assist device ,Descending aorta ,Ventricular fibrillation ,Circulatory system ,cardiovascular system ,Cardiology ,business - Abstract
Circulatory maintenance with a left ventricular assist device (LVAD) alone during cardiac arrest until heart transplantation has been evaluated. To assess the effect on the autonomic nervous system, the sympathetic neurogram was analyzed by power spectrum and coherence function. LVAD were inserted between the left atrium and the descending aorta in seven adult mongrel dogs and ventricular fibrillation was induced electrically. Renal sympathetic nerve activity (RSNA) was detected by bipolar electrodes attached to the left renal sympathetic nerve. Values of squared coherence between the arterial pulse wave and RSNA were calculated. Under the condition of circulatory maintenance with only LVAD, coherence at the cardiac rhythm frequency was decreased, and coherence at the LVAD pumping rhythm frequency was increased. These results indicate that the arterial pulse wave observed during maintenance of the circulation with only LVAD contributed to the sympathetic neurogram.
- Published
- 1992
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- View/download PDF
26. Evaluation of a newly developed continuous protein separation system based on a difference in the isoelectric points of the proteins
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Hirosuke Kobayashi, Minoru Hirose, Toshihiro Shinbo, Kenichi Kokubo, T. Sonobe, and Hiroshi Tsukao
- Subjects
Free-flow electrophoresis ,chemistry.chemical_compound ,Electrophoresis ,Chromatography ,Isoelectric point ,Myoglobin ,chemistry ,Protein purification ,Analytical chemistry ,Selectivity ,Concentration ratio ,Volumetric flow rate - Abstract
Several advanced glycation end products (AGEs) were identified as potential uremic toxins, which were accumulated in patients with end-stage renal disease. Current blood purification technology, however, can not provide a method for separating AGE-modified proteins from normal proteins. The aim of this study was to develop a continuous protein separation system capable of separating AGE-modified proteins from normal proteins. We focused on the change in the isoelectric point of AGE-modified proteins and evaluated a manufactured prototype device based on a free flow electrophoresis. We use myoglobin (isoelectric point: 7.35) solution as a test solution. Protein concentration and pH were measured at varying flow rates (1.3, 3.4, 7.2 mL/min) and voltages (10 and 50 V).When the voltage = 50 V, pH gradient was formed in the electrophoretic chamber after 15 min and myoglobin concentration increase at the center of the electrophoretic chamber. Myoglobin was focusing on sample outlet where the pH of the solution near the isoelectric point. Concentration ratio (maximum / average) was 1.25 -1.30 and had a maximum value at a flow rate of 3.4 mL/min. This newly developed device for continuous protein separation was capable of concentrating myoglobin at the specific position in the electrophoretic chamber and continuously collecting the concentrated myoglobin. However, the concentration ratio of myoglobin was low. The optimization of the operating condition required to improve the selectivity.
- Published
- 2009
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- View/download PDF
27. Burning rate catalysis of azide/nitramine propellants
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T. Sonobe and N. Kubota
- Subjects
Reaction rate ,Propellant ,chemistry.chemical_compound ,Materials science ,chemistry ,Inorganic chemistry ,Flame structure ,Luminous flame ,chemistry.chemical_element ,Azide ,Combustion ,Carbon ,Catalysis - Abstract
In order to improve the burning rate characteristics of azide/nitramine propellants composed of energetic aside polymer and energetic crystalline nitramine particles, the effect of the addition of catalysts on the combustion wave structure was studied. Glycidyl azide polymer (GAP) was used as an energetic azide polymer and cyclotetrametylene tetranitramine (HMX) was used as an energetic nitramine particles. The burning rate of GAP/HMX propellant was increased significantly by the addition of 2.0% lead citrate (PbCi) and 0.6% carbon (C). The measurements of the flame structure and the temperature distribution in the gas phase were conducted with microphotographs and microthermocouples. The results indicate that the luminous flame was produced some distance above the burning surface and the flame standoff distance was increased when the catalyst was added. However, the reaction rate to produce the luminous flame was not affected by the catalyst. Both the heat flux transferred back from the first-stage gas phase zone just above the burning surface and the heat released at the burning surface were determined to be increased by the addition of the catalyst.
- Published
- 1991
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- View/download PDF
28. [The utility of coronary magnetic resonance angiography in children under six years of age with Kawasaki disease]
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A, Takemura, A, Suzuki, T, Kitazume, T, Sonobe, K, Tsuchiya, and T, Korenaga
- Subjects
Male ,Child, Preschool ,Coronary Aneurysm ,Humans ,Infant ,Congresses as Topic ,Mucocutaneous Lymph Node Syndrome ,Child ,Radiology ,Thailand ,Magnetic Resonance Angiography ,Societies, Medical - Abstract
To follow up coronary arterial lesions due to Kawasaki disease (KD) using noninvasive magnetic resonance coronary angiography (MRCA), we studied a method to improve the quality of images in young children.Non-contrast enhanced, free-breathing MRCA with the vector ECG gating real-time navigator-echo 3D steady-state free precession (SSFP) technique was performed using a 1.5-T whole-body MR imaging system (Philips) in 68 children with KD aged 4 months to less than 6 years. A flex medium coil was used. Data were acquired with a 180 to 200 mm field of view (FOV) and were reconstructed with a 512 x 360 matrix. Patients were sedated during the examination. Many parameters were optimized for each patient; i.e., FOV, acquisition delay, turbo-field echo-factor, navigator-window and resolution, which resulted in the acquisition of high-resolution and high-signal images of the coronary arteries.These conditions remarkably improved not only the quality of the images, but also the detection rate of coronary arterial segments (American Heart Association) in the children. The rates were as follows; Segments 1 (97%), 2 (97%), 3 (87%), 4 (66%), 5 (97%), 6 (96%), 7 (83%), 8 (56%), 9 (53%), 10 (21%), 11 (96%), 12 (29%), 13 (93%), 14 (54%), and 15 (65%).MRCA is a useful method for evaluation coronary aneurysms from the early stages of KD, even in infants and small children.
- Published
- 2008
29. Burning rate characteristics of GAP propellants
- Author
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N. Kubota, A. Yamamoto, T. Sonobe, and H. Shimizu
- Subjects
chemistry.chemical_classification ,Propellant ,Temperature sensitivity ,animal structures ,Materials science ,Mechanical Engineering ,Composite number ,Flame structure ,Aerospace Engineering ,Polymer ,Thermal conduction ,Ammonium perchlorate ,Adiabatic flame temperature ,Monopropellant ,chemistry.chemical_compound ,Fuel Technology ,chemistry ,Space and Planetary Science ,Glycidyl azide polymer ,Composite material - Abstract
The burning rate and flame structure of glycidyl azide polymer (GAP)-based composite propellants were examined in order to obtain a wide spectrum of burning rates. Crystalline fine particles of ammonium perchlorate, cyclotetramethylene tetranitramine, or triaminoguanidine nitrate, were mixed within GAP to formulate GAP propellants. Since GAP is an energetic self-sustaining combustible polymer, the burning rate characteristics of GAP propellants appeared to be fundamentally different from those of conventional composite propellants. Measured results indicate that the burning rate, pressure exponent, temperature sensitivity, and flame structure depend largely on the concentration of the crystalline additives. The observed burning rate characteristics were correlated with the concentration of the crystalline particles.
- Published
- 1990
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- View/download PDF
30. Effect of Left Ventricular Assistance on Sympathetic Tone
- Author
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Hitoshi Mohri, Hiroshi Takeda, Makoto Yoshizawa, Shin-ichi Nitta, Makoto Miura, T. Sonobe, Yoshiaki Katahira, Tomoyuki Yambe, Masaru Tanaka, and N. Satoh
- Subjects
Male ,medicine.medical_specialty ,Sympathetic nervous system ,Sympathetic Nervous System ,medicine.medical_treatment ,Neural Conduction ,030232 urology & nephrology ,Biomedical Engineering ,Medicine (miscellaneous) ,Bioengineering ,030204 cardiovascular system & hematology ,Baroreflex ,Kidney ,law.invention ,Biomaterials ,03 medical and health sciences ,Dogs ,Renal Artery ,0302 clinical medicine ,law ,Internal medicine ,Artificial heart ,medicine.artery ,medicine ,Animals ,Sympathetic tone ,business.industry ,General Medicine ,Ventricular assistance ,Electrodes, Implanted ,medicine.anatomical_structure ,Blood pressure ,Ventricular assist device ,Pulmonary artery ,Cardiology ,Female ,Vascular Resistance ,Heart-Assist Devices ,business - Abstract
To determine the effect of left ventricular assist device (LVAD) pumping on sympathetic tone, renal sympathetic nerve activity (RSNA) was detected in acute animal experiments. Our TH-7B pneumatically driven, sac-type ventricular assist device was used in 7 adult mongrel dogs. RSNA was detected by the use of bipolar electrodes attached to the left renal sympathetic nerve. RSNA was amplified and integrated by use of an R-C integrator circuit. The area of the integrated nerve discharge per unit time was calculated in the computer system and expressed as RSNA per unit time. During LVAD pumping, RSNA decreased with increase in blood pressure, with an increase in pulmonary artery flow, and with a decrease in left atrial pressure. These data suggest that LVAD has an effect on the sympathetic nervous system which is mediated by the aortic and cardiopulmonary baroreflex system.
- Published
- 1990
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- View/download PDF
31. OPLEAF connecting optical fibers to ifigh density optical IC
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Y. Nakano, Hiroyuki Fujita, T. Sonobe, and N. Hiroi
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Optical fiber ,Materials science ,Silicon photonics ,genetic structures ,business.industry ,Microstructured optical fiber ,Waveguide (optics) ,eye diseases ,law.invention ,Slot-waveguide ,law ,Fiber optic splitter ,Optoelectronics ,sense organs ,Plastic optical fiber ,business ,Photonic-crystal fiber - Abstract
We have designed and fabricated an OPLEAF (OPtical LEAd Frame) that serves as the interface between optical fibers and a high density optical IC. The OPLEAF is a micromachined structure for converting an optical fiber array pitch from 250 mum to 30 mum and aligning thinned fibers to the optical IC
- Published
- 2006
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- View/download PDF
32. Planarized SiO/sub 2/ formation by a new microwave plasma system
- Author
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T. Sonobe, Michio Ohue, Fukuda Takuya, T. Kikuchi, N. Momma, and K. Suzuki
- Subjects
Materials science ,Sputtering ,Chemical-mechanical planarization ,Analytical chemistry ,Biasing ,Substrate (electronics) ,Plasma ,Plasma processing ,Ion source ,Ion - Abstract
An improved microwave plasma system is proposed to form planarized SiO/sub 2/ interlayers for LSIs. A high planarization rate was achieved by controlling the formation of a cylindrical plasma and by adjusting the frequency applied to the substrate by which ions can be impinged onto the substrate at a maximum speed. Electric damage was decreased by using oxygen ion sputtering and by suppressing the stimulated bias voltage. These features ensure that a low-damage, planarized SiO/sub 2/ film is formed at a rate of more than 200 nm/min without a stimulated bias voltage. >
- Published
- 2003
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- View/download PDF
33. The influence of oxide formation on the solder acceptance of thick-film copper conductors
- Author
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K. Ban, T. Nagasaka, M. Koyama, H. Nakagawara, and T. Sonobe
- Subjects
chemistry.chemical_compound ,Materials science ,chemistry ,Soldering ,Metallurgy ,Oxide ,chemistry.chemical_element ,Grain boundary ,Solderability ,Electrical conductor ,Phosphoric acid ,Copper ,Conductor - Abstract
Results of an examination of the nature of oxide formation on the surface of copper conductors are reported and a method to remove oxides from them to improve solderability is presented. The oxide formed is Cu/sub 2/O, and it takes the form of small grains, approximately 2 to 10 micrometers in diameter, centered around the copper grain boundaries. As the amount of Cu/sub 2/O increases, the solderability decreases accordingly, with an increase in the number of firing cycles. The Cu/sub 2/O can be removed completely and solderability can be improved by soaking the copper conductors in a phosphoric acid solution and using an appropriate type of flux for soldering. Further tests were conducted which showed that any change in the formation of copper grains and Cu/sub 2/O did not affect conductor resistance and adhesion. These findings pave the way for wider use of thick-film, multilayer copper conductors. >
- Published
- 2003
- Full Text
- View/download PDF
34. X-ray identification of the soft γ-ray repeater 1806 – 20
- Author
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Yasuo Tanaka, Toshio Murakami, Shrinivas R. Kulkarni, T. Sonobe, T. Aoki, A. Yoshida, Y. Ogasaka, and Y. Ogawara
- Subjects
Physics ,Supernova ,Nebula ,Neutron star ,Multidisciplinary ,Pulsar ,Observatory ,Coincident ,Astrophysics::High Energy Astrophysical Phenomena ,Soft gamma repeater ,Gamma ray ,Astronomy ,Astrophysics - Abstract
The nature of γ-ray bursters—astrophysical sources that emit abrupt bursts of γ-rays—presents a long-standing question in high-energy astronomy. Soft γ-ray repeaters (SGRs) are distinguished from classical γ-ray bursters by the short duration, softer γ-ray spectrum and recurrent activity of their outbursts. Millisecond-scale structure in these bursts suggests that SGRs are compact, and many models invoke neutron stars as the emitting objects. This idea is supported by the association of two SGRs, SGR0526 – 66 (ref. 6) and SGR1806 – 20 (ref. 7), with supernova remnants, SNR N49 and the radio nebula G10.0 – 0.3 respectively. Very recently, Kulkarni et al. have suggested that a compact radio source in G10.0 – 0.3 corresponds to a young pulsar at the centre of this nebula, and can be identified with SGR1806 – 20. Here we report the detection of a burst from SGR1806 – 20 with the X-ray satellite ASCA10, which allows us to identify the burster with a new X-ray source which we designate AX1805.7 – 2025. The burst is coincident in time with that detected by the BATSE instrument on board the Compton Gamma Ray Observatory. This result provides strong evidence that SGRs are indeed neutron stars.
- Published
- 1994
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- View/download PDF
35. Epidemiologic and clinical characteristics of Kawasaki disease in Shaanxi Province, China, 1993-1997
- Author
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F, Jiao, L, Yang, Y, Li, J, Qiao, X, Guo, T, Zhang, T, Kawasaki, T, Sonobe, and H, Yanagawa
- Subjects
Male ,China ,Adolescent ,Incidence ,Infant, Newborn ,Infant ,Mucocutaneous Lymph Node Syndrome ,Age Distribution ,Cardiovascular Diseases ,Child, Preschool ,Humans ,Female ,Seasons ,Sex Distribution ,Child - Abstract
The objective of this paper is to describe the epidemiological and clinical characteristics of Kawasaki disease (KD) in Shaanxi Province, China during the 5-year period from January 1993 to December 1997. A province-wide epidemiological survey on KD was made by the China-Japan Kawasaki Disease Study Group. The questionnaire form and the diagnostic criteria of KD, which were prepared by the Japan Kawasaki Disease Research Committee and translated into Chinese, were sent to the departments of pediatrics of all the hospitals with 100 beds or more in Shaanxi province. All the KD patients who were diagnosed during the observation period from 1993 to 1997 were asked to take part in this survey. The databases of reported KD in this survey were analysed at the Department of Pediatrics of the Shaanxi Provincial People's Hospital, Xi'an, China. All the patients that satisfied the diagnostic criteria were included in the report. A total of 105 (70 per cent) hospitals responded and 376 cases of KD were confirmed. More cases were reported in 1993 and 1994. Of the total patients reported, 69 per cent were children under 3 years old with a male to female ratio of 1.6:1. The proportion of patients with cardiac sequelae was 19 per cent with a male to female ratio of 3:1. There were four fatal cases with a fatality rate of 1 per cent. It is concluded that KD is common in China. Continuous surveillance is necessary to maintain high awareness of KD so as to find possible risk factors and their association with the disease.
- Published
- 2001
36. [Evaluations of MTD and Amplicor Mycobacterium for direct detection of Mycobacteria from clinical specimens]
- Author
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A, Sato, T, Sonobe, M, Okazaki, and B, Umeda
- Subjects
Bacteriological Techniques ,Gene Amplification ,Humans ,Molecular Probe Techniques ,Tuberculosis ,Mycobacterium tuberculosis ,DNA Probes ,Mycobacterium avium Complex ,Sensitivity and Specificity ,Mycobacterium avium-intracellulare Infection - Abstract
MTD (GEN-PROBE AMPLIFIED MYCOBACTERIUM TUBERCULOSIS DIRECT TEST) for Mycobacterium tuberculosis, and Amplicor Mycobacterium for Mycobacteria (AMP-M. tb for M. tuberculosis, AMP-M. av for M. avium and AMP-M. in for M. intracellulare) were used for the detection of relevant Mycobacterium. Their sensitivity and specificity were evaluated. Total 244 clinical specimens including 164 sputa were examined by the above two tests. The results were compared with those obtained by the conventional methods. Of 244 samples, number of the M. tuberculosis positive samples by microscopy, cultural test, MTD and AMP-M. tb were 32, 33, 38 and 35, respectively. Among 33 culture positive samples, 25 were MTD positive and 26 were AMP-M. tb positive. Therefore, sensitivity of MTD and AMP-M. tb were 75.8% and 78.8%, and their specificity were 93.8% and 95.7%, respectively. When only sputa were used for the tests as the clinical specimens, both sensitivity of MTD and AMP-M. tb were increased to 94.4%. For MAC, positive samples of M. avium complex by culture, M. avium by AMP-M. av and M. intracellulare by AMP-M. in were 13, 16, and 8, respectively. Sensitivity and specificity of AMP-M. av/M. in were 100% and 95.2%, respectively. Clinical findings of the patients whose MTD tests were positive but negative by culture were reexamined. Three of 9 specimens were also positive in AMP-M. tb. From the records of the isolations of tubercle bacilli or other important pathogens from the other kind of clinical specimens, smear tests and patients' response to tuberculosis chemotherapy, four of 9 specimens were confirmed as true positive, three were suspected as positive, and two other specimens were false positive which might be caused by contamination. From these observations, it could be concluded that MTD and AMP-M. tb are more sensitive than conventional culture method, and MTD is more sensitive than AMP-M. tb but needs more careful treatment to avoid the contamination.
- Published
- 1999
37. Development of vibrating flow pump for left ventricular assist circulation
- Author
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Shinichi Kobayashi, Kazuhiko Shizuka, T. Sonobe, Tomoyuki Yambe, Shin-ichi Nitta, T. Fkuju, Hiroyuki Hashimoto, and S. Nannka
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,030232 urology & nephrology ,Biomedical Engineering ,Medicine (miscellaneous) ,Hemodynamics ,Bioengineering ,Heart, Artificial ,030204 cardiovascular system & hematology ,Vibration ,law.invention ,Biomaterials ,03 medical and health sciences ,0302 clinical medicine ,law ,Internal medicine ,medicine ,Waveform ,Animals ,Frequency analysis ,business.industry ,Goats ,General Medicine ,Blood flow ,Stroke volume ,Blood pump ,medicine.anatomical_structure ,Ventricular assist device ,Pulsatile Flow ,Vascular resistance ,Cardiology ,Heart-Assist Devices ,business - Abstract
Vibrating flow pump (VFP) can generate high frequency oscillated blood flow within 1040 Hz. In this study, new type VFP was developed as a ventricular assist device. Left Ventricular assist circulation using VFP were performed as aseptic animal experiments using goats, hemodynamic parameters were recorded continuously at awaked state. Driving frequency of VFP was 25 Hz and pump flow rate was controlled to approximately 2 l/min. Frequency of VFP was 25 hz and pump flow rate was controlled to approximately 2 L/min. Frequency analysis method was used for analyzing hemodynamics. The peak of power was observed at 25 Hz from the Fourier transformation of blood flow waveform. Systemic vascular resistance was decreased by the start of left ventricular assistance using oscillated blood flow. No fatal arrhythmia was osberved during this study. As the conclusion, new type VFP has a sufficient performance for left ventricular assistance. Small size blood pump may be enabled by the oscillated blood flow because VFP is driven at high frequency moving with short stroke volume.
- Published
- 1998
38. Nasal absorption kinetic behavior of azetirelin and its enhancement by acylcarnitines in rats
- Author
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S, Kagatani, N, Inaba, M, Fukui, and T, Sonobe
- Subjects
Male ,Nasal Mucosa ,Dose-Response Relationship, Drug ,Carnitine ,Animals ,Azetidines ,Drug Synergism ,Dipeptides ,Hydrogen-Ion Concentration ,Rats, Inbred F344 ,Absorption ,Rats - Abstract
The long-term stability and nasal absorption characteristics of a basic nasal formulation of azetirelin, a thyrotropin-releasing hormone analog and its absorption enhancement by incorporation of acylcarnitines in the formulation were investigated.The long-term stability of basic nasal azetirelin formulations at 25 degrees C was predicted by calculation from the Arrhenius plot of the data on 6 months' storage at 40, 50 and 60 degrees C. Nasal azetirelin absorption characteristics were kinetically examined by intranasal administration to rats, determination of plasma azetirelin level by radioimmunoassay, and fitting the data to a two-compartment model including absorption rate.Basic nasal azetirelin formulations of pH 4.0 and pH 5.1 were predicted to be highly stable. Residual azetirelin after 2 years storage at 25 degrees C was greater than 95%. Nasal absorption characteristics of this formulation in the pH 4.0-6.3 range showed pH-dependency, with pH 4.0 showing the highest absolute bioavailability (Bioav) of 17.1%. This nasal Bioav was 21 times greater than that of oral administration (0.8%). Acylcarnitines with 12 or more carbon atoms in the acyl chain greatly enhanced nasal absorption of azetirelin: Bioavs with lauroylcarnitine chloride (LCC) and palmitoylcarnitine chloride were 96.9% and 72.9%, respectively. This enhancement by LCC plateaued at the low concentration of 0.1%.The basic nasal azetirelin formulation at pH 4.0 is stable and shows adequate absorption, with nasal absorption having greater Bioav than oral absorption. The 12-carbon acylate LCC was the strongest enhancer among acylcarnitines and provided near-total delivery of the administered dose to the blood.
- Published
- 1998
39. Development of intracoronary local adhesive delivery technique
- Author
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Yoshiaki Katahira, T. Sonobe, Shigeru Naganuma, Shinichi Kobayashi, Sizuka K, Shin-ichi Nitta, Keiko Nitta, and Tomoyuki Yambe
- Subjects
Male ,medicine.medical_specialty ,0206 medical engineering ,Biomedical Engineering ,Medicine (miscellaneous) ,Bioengineering ,Coronary Disease ,02 engineering and technology ,Dissection (medical) ,law.invention ,Absorption ,Biomaterials ,Drug Delivery Systems ,Fibrinolytic Agents ,law ,Intravascular ultrasound ,Occlusion ,medicine ,Myocardial Revascularization ,Animals ,Cyanoacrylates ,Thrombus ,Angioplasty, Balloon, Coronary ,medicine.diagnostic_test ,business.industry ,Goats ,General Medicine ,021001 nanoscience & nanotechnology ,medicine.disease ,020601 biomedical engineering ,Surgery ,Catheter ,Disease Models, Animal ,Coronary occlusion ,Cyanoacrylate ,Drug delivery ,Feasibility Studies ,Female ,Stents ,Tissue Adhesives ,0210 nano-technology ,business - Abstract
Acute coronary occlusion may occur in weak coronary atherosclerotic lesions, including dissection, ulceration or thrombus. In some cases of occlusion “bail-out” is performed by using recently developed New Devices. However, these have not yet completely solved the problem to this end, we designed a new method of coronary revascularization, the Intracoronary Local Adhesive Delivery Technique, utilizing antithrombotic and absorbable adhesive injected locally into the fragile and morbid arterial wall using a drug delivery PTCA catheter more flexible than the existing New Devices. This adhesive strengthened and hardened the lesions. In this study, we examined the efficacy of making an adhesive cylinder in arteries of similar size to the coronary, through acute animal experiments using the existing clinical adhesives and drug delivery PTCA catheters and 12 femoral arteries of adult goats. We were successful in forming firm tunnels along the inside of six arteries, infused with approximately 0.04 ml Cyanoacrylate. These tunnels were observed with intravascular ultrasound (IVUS) imaging and evaluated microscopically. These results suggest the feasibility of this method as a new approach for making synthetic resinous stents.
- Published
- 1997
40. Development and evaluation of totally implantable ventricular assist system using a vibrating flow pump and transcutaneous energy transmission system with amorphous fibers
- Author
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T, Yambe, H, Hashimoto, S, Kobayashi, T, Sonobe, S, Naganuma, S S, Nanka, H, Matsuki, M, Yoshizawa, K, Tabayashi, H, Takayasu, H, Takeda, and S, Nitta
- Subjects
Heart Bypass, Left ,Goats ,Hemodynamics ,Models, Cardiovascular ,Equipment Design ,Heart, Artificial ,Vibration ,Fractals ,Nonlinear Dynamics ,Evaluation Studies as Topic ,Coronary Circulation ,Animals ,Heart-Assist Devices ,Electromagnetic Phenomena - Abstract
We have developed a vibrating flow pump (VFP) that can generate oscillated blood flow with a relatively high frequency (10-50 Hz) for a totally implantable ventricular assist system (VAS). To evaluate the newly developed VAS, left heart bypasses, using the VFP, were performed in chronic animal experiments. Hemodynamic parameters were recorded in a data recorder in healthy adult goats during an awake condition and analyzed in a personal computer system through an alternating-direct current converter. Basic performance of the total system with a transcutaneous energy transmission system were satisfactory. During left ventricular assistance with the VFP, Mayer wave fluctuations of hemodynamics were decreased in the power spectrum, the fractal dimensions of the hemodynamics were significantly decreased, and peripheral vascular resistance was significantly decreased. These results suggest that cardiovascular regulatory nonlinear dynamics, which mediate the hemodynamics, may be affected by left ventricular bypass with oscillated flow. The decreased power of the Mayer wave in the spectrum caused the limit cycle attractor of the hemodynamics and decreased peripheral resistance. These results suggest that this newly developed VAS is useful for the totally implantable system with unique characteristics that can control hemodynamic properties.
- Published
- 1997
41. Enhancement of nasal salmon calcitonin absorption by lauroylcarnitine chloride in rats
- Author
-
S, Kagatani, T, Shinoda, M, Fukui, T, Ohmura, S, Hasumi, and T, Sonobe
- Subjects
Calcitonin ,Male ,Rats, Sprague-Dawley ,Area Under Curve ,Carnitine ,Osmolar Concentration ,Animals ,Biological Availability ,Hydrogen-Ion Concentration ,Administration, Intranasal ,Laurates ,Rats - Abstract
We investigated optimum formulation characteristics in the nasal absorption of salmon calcitonin (sCT) by incorporation of acylcarnitines.Nasal sCT formulations were administered to anesthetized rats. Plasma calcium level was measured and pharmacological bioavailability (P.bioav) was calculated.Nasal sCT absorption was significantly enhanced by carnitines with acyl groups of 12 or more carbon atoms. Enhancement by lauroylcarnitine chloride (LCC) was observed at its critical micelle concentration and reached a plateau at the concentration of 0.1 percent. Optimal absorption was achieved at a molar ratio of LCC to sCT of 5:1. Enhancement was not influenced by osmolarity and maximum enhancement was obtained at pHs 3.1 and 4.0.The 12-carbon LCC was the strongest enhancer among acylcarnitines. Micelle formation played a key role in this enhancement effect.
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- 1996
42. Deterministic chaos in the hemodynamics of an artificial heart
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T, Yambe, S, Nitta, T, Sonobe, S, Naganuma, Y, Kakinuma, K, Izutsu, H, Akiho, S, Kobayashi, N, Ohsawa, and S, Nanka
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Disease Models, Animal ,Nonlinear Dynamics ,Coronary Circulation ,Goats ,Ventricular Fibrillation ,Hemodynamics ,Animals ,Blood Pressure ,Heart, Artificial ,Heart-Assist Devices - Abstract
To analyze the hemodynamic parameters during prosthetic circulation as an entity, non linear mathematical techniques were used. To compare natural and prosthetic circulation, two pneumatically actuated ventricular assist devices were implanted as biventricular bypasses in chronic animal experiments using adult goats to consitute the biventricular bypass complete prosthetic circulation model with ventricular fibrillation. After implantation, these goats were placed in a cage and extubated after waking. All hemodynamic parameters with the natural circulation without biventricular bypass pumping, and the artificial circulation with biventricular bypass pumping under ventricular fibrillation were recorded under awake conditions. By the use of a non linear mathematical technique, the arterial blood pressure waveform was embedded into a four dimensional phase space and projected into three dimensional phase space. The Lyapunov numeric method is used as an adjunct to the graphic analysis of the state space. A phase portrait of the attractor showed a high dimension complex structure, with three dimensional solid torus suggesting deterministic chaos during natural circulation. However, a simple attractor, such as a limit cycle attractor, was observed during artificial circulation. Positive Lyapunov exponents during artificial circulation suggest the lower dimensional chaotic system. Thus, hemodynamic parameters during prosthetic circulation must be carefully controlled when unexpected stimuli are fed from outside.
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- 1995
43. X-ray identification of SGR1806−20
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S. R. Kulkarni, A. Yoshida, T. Aoki, Y. Ogasaka, T. Sonobe, and T. Murakami
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On board ,Physics ,Neutron star ,Point source ,Coincident ,Astrophysics::High Energy Astrophysical Phenomena ,X-ray ,Astronomy ,Astrophysics ,Supernova remnant ,Gamma-ray burst ,Short duration ,Astrophysics::Galaxy Astrophysics - Abstract
Among gamma‐ray burst sources (GRBs) three clearly repeat (SGR) and produce bursts that distinguish themselves from ‘‘classical’’ gamma‐ray bursts by having a soft spectrum and a short duration. However, no conclusive identification of an SGR burst with a compact source has yet been made. We report here the identification of SGR1806−20 with AX1805.7−2025, a new, persistent x‐ray source, by the imaging of a burst with the Japanese x‐ray satellite ASCA. The burst is coincident in time with that detected by BATSE on board the CGRO. The position of the x‐ray source is coincident with the point source in the supernova remnant (SNR) G10.0–0.3, which was identified as the radio counterpart by Kulkarni et al. This result provides strong evidence for a neutron star origin of SGRs.
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- 1994
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44. P1-344 Coronary artery lesions of incomplete kawasaki disease: the Nationwide survey of 2007-2008 in Japan
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M Yashiro, M Mieno, D Sudo, T Sonobe, Yosikazu Nakamura, Ritei Uehara, Y Monobe, and K Tsuchiya
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medicine.medical_specialty ,Epidemiology ,business.industry ,Public Health, Environmental and Occupational Health ,medicine.disease ,Nationwide survey ,Surgery ,Steroid therapy ,medicine.anatomical_structure ,hemic and lymphatic diseases ,Internal medicine ,Total dose ,medicine ,Kawasaki disease ,In patient ,business ,IVIG Therapy ,Pathological ,Artery - Abstract
Objectives To observe the recent epidemiologic features of incomplete Kawasaki disease (KD) patients reported to the Japanese nationwide survey, and to compare risk factors for developing coronary artery lesions (CALs) between incomplete KD and complete KD. Methods In the 2007–2008 nationwide survey, 23 337 KD patients were reported and then classified by their number of principal symptoms for analyses. In this study, complete KD was defined as having five or more of the six principal symptoms; incomplete KD as having four or fewer regardless of the presence or absence of CALs. Results Compared with complete KD patients, younger ages at first hospital visit, a higher incidence rate of CALs, less frequency of both initial and additional intravenous immunoglobulin (IVIG) administration, later IVIG administration, less total dose of IVIG administration, and less frequency of steroid therapy were observed among those with incomplete KD. Also particularly in patients having CALs, the same delayed and insufficient IVIG therapy was observed in incomplete KD. Multivariate analysis showed that the risk factors for CALs observed in incomplete KD were almost the same as those observed in complete KD, except for receiving initial IVIG therapy. The initial IVIG administration was risk of developing CALs in incomplete KD, but not risk rather protective in complete KD. Conclusions The results imply the existence of a common pathological basis in generating CALs regardless of presentation types of KD. Therefore, more timely diagnosis and treatment to incomplete KD patients could lead to the further prevention of cardiac lesions caused by KD.
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- 2011
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45. Identification of the deterministic chaos in cardiovascular dynamics by the use of the non-linear mathematics
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T, Yambe, S, Nitta, T, Sonobe, S, Naganuma, S, Kobayashi, Y, Haga, M, Tanaka, T, Fukuju, M, Miura, and N, Sato
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Cardiovascular Physiological Phenomena ,Nonlinear Dynamics ,Goats ,Animals ,Blood Pressure ,Cardiac Output - Abstract
Chaotic behavior in cardiovascular dynamics was thought to be one of the important information to analyze the circulatory regulatory system. Several investigators studied the attractor in the signals of the electrocardiogram, and found the strange attractor, suggesting dynamics compatible with deterministic chaos, by the use of the non-linear mathematics. It is interesting problem to analyze the hemodynamic parameters by the use of non-linear mathematics for the determination of the physiologically optimal circulatory condition. In this study, Chaos analyzing system was developed to identify the deterministic chaos in cardiovascular regulatory system by the use of the non-linear mathematics including phase plane plots, embedding, and lyapunov exponents. Time series data of the hemodynamic parameters in the chronic animal experiments was analyzed by this system, and satisfactory attractor was obtained by the use of the phase plane plots and embedding techniques. Furthermore, calculation of the lyapunov exponents showed the existence of the deterministic chaos in arterial blood pressure in the chronic animal experiments using adult goats, suggesting this tool is useful for analyzing cardiovascular dynamic behavior.
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- 1993
46. Dependence of baroreceptor-mediated sympathetic outflow on biventricular assist device driving frequency
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T, Yambe, S, Nitta, Y, Katahira, T, Sonobe, S, Naganuma, Y, Kakinuma, H, Akiho, K, Izutsu, Y, Kikuchi, and M, Tanaka
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Dogs ,Sympathetic Nervous System ,Heart Rate ,Animals ,Heart ,Pressoreceptors ,Heart-Assist Devices - Abstract
To investigate the drive condition of the artificial heart from a neurophysiological point of view, the dynamic transduction characteristics of the baroreflex system were analyzed by means of sympathetic neurograms. Two pneumatically actuated ventricular assist devices were implanted as biventricular bypasses (BVBs) in adult mongrel dogs to compare the natural heart circulation and prosthetic circulation. After BVB pumping was initiated, the natural heart was electrically fibrillated. Renal sympathetic nerve activity (RSNA) was recorded to analyze sympathetic outflow. Coherence function between the arterial pressure and RSNA was calculated to evaluate the linearity of the baroreflex system. The largest peak coherency was observed when BVB was driven at the frequency of natural heart beat prior to electrical fibrillation, which suggests that the baroreflex system shows the largest linearity at this frequency. These results suggest the possibility that the natural heart beat frequency is the setting frequency at which the baroreflex system transfers the hemodynamic rhythm to the sympathetic outflow.
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- 1993
47. Fundamental rhythm of sympathetic nerve discharges in animals with total artificial hearts
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T, Yambe, S, Nitta, Y, Katahira, T, Sonobe, S, Naganuma, Y, Kakinuma, H, Matsuzawa, M, Tanaka, M, Miura, and N, Sato
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Male ,Dogs ,Sympathetic Nervous System ,Ventricular Fibrillation ,Animals ,Blood Pressure ,Female ,Heart, Artificial ,Heart-Assist Devices ,Kidney ,Electric Stimulation - Abstract
To evaluate the effect of total artificial heart replacement on the autonomic nervous system, sympathetic neurograms were analyzed by power spectrum and coherence function. Two pneumatically driven, sac type ventricular assist devices were implanted as biventricular bypasses (BVB) in adult, mongrel dogs. After initiation of BVB pumping, the natural heart was electrically fibrillated to form a BVB TAH model. Renal sympathetic nerve activity (RSNA) was recorded using a bipolar electrode attached to the left renal sympathetic nerve. RSNA was amplified and integrated by use of an R-C integrator. Power spectra of the RSNA and values of squared coherence between the arterial pressure wave form and the RSNA were calculated by computer. In animals with total artificial hearts (TAHs), coherence at the cardiac rhythm frequency was decreased, and coherence at the TAH pumping rhythm frequency was increased. These results indicate that the arterial pulse wave observed in TAH animals contributed to the sympathetic neurogram.
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- 1992
48. Cardiac-related sympathetic nerve activity during circulation with only the left ventricular assist device
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T, Yambe, S, Nitta, Y, Katahira, T, Sonobe, S, Naganuma, H, Akiho, S, Chiba, Y, Kakinuma, H, Hayashi, and K, Izutsu
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Male ,Dogs ,Sympathetic Nervous System ,Reflex ,Ventricular Fibrillation ,Hemodynamics ,Animals ,Female ,Heart ,Pressoreceptors ,Heart-Assist Devices ,Kidney ,Myocardial Contraction - Abstract
Circulatory maintenance with a left ventricular assist device (LVAD) alone during cardiac arrest until heart transplantation has been evaluated. To assess the effect on the autonomic nervous system, the sympathetic neurogram was analyzed by power spectrum and coherence function. LVAD were inserted between the left atrium and the descending aorta in seven adult mongrel dogs and ventricular fibrillation was induced electrically. Renal sympathetic nerve activity (RSNA) was detected by bipolar electrodes attached to the left renal sympathetic nerve. Values of squared coherence between the arterial pulse wave and RSNA were calculated. Under the condition of circulatory maintenance with only LVAD, coherence at the cardiac rhythm frequency was decreased, and coherence at the LVAD pumping rhythm frequency was increased. These results indicate that the arterial pulse wave observed during maintenance of the circulation with only LVAD contributed to the sympathetic neurogram.
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- 1992
49. Systemic circulation with high frequency blood flow--analysis from neurophysiological point of view
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T, Yambe, S, Nitta, Y, Katahira, T, Sonobe, S, Naganuma, Y, Kakinuma, H, Akiho, M, Tanaka, T, Fukuju, and M, Miura
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Regional Blood Flow ,Goats ,Blood Circulation ,Animals ,Blood Pressure ,Heart, Artificial - Abstract
The vibrating electromagnetically driven univalved artificial heart, which provided more than 10 1/min at 10 Hz/sec. vibration, was developed in our team. This vibrating electromagnetic pump (VEMP) produced the original flow pattern compared with the flow pattern of the natural heart, so that circulatory regulatory system during maintain the circulation with VEMP must be investigated before the clinical application. In order to assess the effect of high frequency blood flow produced by the VEMP from the neurophysiological point of view, power spectral analysis of the hemodynamics was performed. VEMP was implanted as the total left heart bypass in adult goats and right heart circulation was maintained by natural hearts. In arterial blood pressure during maintain circulation by the high frequency blood flow, Mayer waves (0.01-0.15 Hz) were significantly decreased, though respiratory waves (0.25-0.40 Hz) were not significantly changed. These results suggest that circulatory regulatory system was influenced by the high frequency blood flow produced by the VEMP.
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- 1991
50. Development and clinical evaluation of the long time digital Holter ECG system using non-tracking technology
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S, Nitta, T, Yambe, Y, Katahira, T, Sonobe, S, Naganuma, S, Chiba, Y, Kakinuma, M, Tanaka, M, Miura, and N, Sato
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Adult ,Evaluation Studies as Topic ,Electrocardiography, Ambulatory ,Humans - Abstract
Newly developed long time digital Holter ECG system utilizing a stamp-size non-tracking (NT) tape which can be used for 192 hours as 2ch recording, was evaluated in the clinical cases. The system has employed newly developed VLSIs and NT technology which enables to obtain reliable long time recording with smaller and lighter Holter system of ECG and variety of biological signals. The results indicated that good data reproduction was shown in this system.
- Published
- 1991
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