1,109 results on '"Y HIRAYAMA"'
Search Results
102. Microsomal prostaglandin E synthase-1 contributes to ischaemic excitotoxicity through prostaglandin E2 EP3 receptors
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Y, Ikeda-Matsuo, H, Tanji, A, Ota, Y, Hirayama, S, Uematsu, S, Akira, and Y, Sasaki
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Male ,Research Papers with Commentaries ,Receptors, Prostaglandin ,Brain Edema ,In Vitro Techniques ,Brain Ischemia ,Mice ,Microsomes ,Animals ,Humans ,Receptors, Prostaglandin E ,Excitatory Amino Acid Agents ,RNA, Messenger ,Rats, Wistar ,CA1 Region, Hippocampal ,Prostaglandin-E Synthases ,Mice, Knockout ,Neurons ,rho-Associated Kinases ,Infarction, Middle Cerebral Artery ,Rats ,Intramolecular Oxidoreductases ,Mice, Inbred C57BL ,Neuroprotective Agents ,Cyclooxygenase 2 ,Ischemic Attack, Transient ,Reperfusion Injury ,Receptors, Prostaglandin E, EP3 Subtype ,Prostaglandins ,Female ,Signal Transduction - Abstract
Although microsomal prostaglandin E synthase (mPGES)-1 is known to contribute to stroke injury, the underlying mechanisms remain poorly understood. This study examines the hypothesis that EP(3) receptors contribute to stroke injury as downstream effectors of mPGES-1 neurotoxicity through Rho kinase activation.We used a glutamate-induced excitotoxicity model in cultured rat and mouse hippocampal slices and a mouse middle cerebral artery occlusion-reperfusion model. Effects of an EP(3) receptor antagonist on neuronal damage in mPGES-1 knockout (KO) mice was compared with that in wild-type (WT) mice.In cultures of rat hippocampal slices, the mRNAs of EP(1-4) receptors were constitutively expressed and only the EP(3) receptor antagonist ONO-AE3-240 attenuated and only the EP(3) receptor agonist ONO-AE-248 augmented glutamate-induced excitotoxicity in CA1 neurons. Hippocampal slices from mPGES-1 KO mice showed less excitotoxicity than those from WT mice and the EP(3) receptor antagonist did not attenuate the excitotoxicity. In transient focal ischaemia models, injection (i.p.) of an EP(3) antagonist reduced infarction, oedema and neurological dysfunction in WT mice, but not in mPGES-1 KO mice, which showed less injury than WT mice. EP(3) receptor agonist-induced augmentation of excitotoxicity in vitro was ameliorated by the Rho kinase inhibitor Y-27632 and Pertussis toxin. The Rho kinase inhibitor HA-1077 also ameliorated stroke injury in vivo.Activity of mPGES-1 exacerbated stroke injury through EP(3) receptors and activation of Rho kinase and/or G(i). Thus, mPGES-1 and EP(3) receptors may be valuable therapeutic targets for treatment of human stroke.
- Published
- 2010
103. Comparison of Starch Levels Reduced by High Temperature During Ripening in Japonica Rice Lines Near-Isogenic for the Wx Locus
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Tsuyoshi Inukai and Y. Hirayama
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chemistry.chemical_classification ,biology ,Starch ,food and beverages ,Ripening ,Plant Science ,biology.organism_classification ,Polysaccharide ,Japonica ,Endosperm ,chemistry.chemical_compound ,chemistry ,Agronomy ,Biochemistry ,Amylose ,Amylopectin ,biology.protein ,Food science ,Starch synthase ,Agronomy and Crop Science - Abstract
One problem caused by high temperature during ripening in Japonica rice cultivars is a reduction in the amount of starch in the endosperm. To better understand this deleterious effect, we compared the accumulation of the two components of starch, amylose and amylopectin in grains ripened at high (32/28 °C) and low (22/18 °C) day/night temperatures in a set of lines of Japonica cultivar Taichung 65 (T65Wx b ) that are near-isogenic for the Wx locus, which encodes granule-bound starch synthase I. In T65Wx b ripened at high temperature, the amount of starch per grain decreased. However, amylose per grain significantly decreased while amylopectin per grain significantly increased. On the other hand, the amount of amylopectin in T65wx, the amylose-free line, did not differ significantly at the high and low temperatures. These data indicated that high temperatures during ripening did not directly affect amylopectin accumulation in T65Wx b and that the reduction in starch in T65Wx b from the high temperatures was caused by a decrease only of amylose. The results for T65Wx a and T65Wx op were also consistent with this conclusion. As a result of the decrease in amylose, the outer region of starch granules from T65Wx b ripened at the high temperatures also had less I 2 KI staining. Because this fact might suggest that a portion of amylose was synthesized inside the developing granules after amylopectin synthesis in rice, the effect of amylose deposition in increasing of the density of starch granules is also discussed.
- Published
- 2010
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104. Microsomal prostaglandin E synthase-1 and cyclooxygenase-2 are both required for ischaemic excitotoxicity
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Y, Ikeda-Matsuo, Y, Hirayama, A, Ota, S, Uematsu, S, Akira, and Y, Sasaki
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Male ,Mice, Knockout ,Neurons ,Cyclooxygenase 2 Inhibitors ,Glutamic Acid ,Hippocampus ,Research Papers ,Dinoprostone ,Brain Ischemia ,Rats ,Intramolecular Oxidoreductases ,Mice, Inbred C57BL ,Stroke ,Disease Models, Animal ,Mice ,Cyclooxygenase 2 ,Microsomes ,Reperfusion Injury ,Animals ,Female ,Prostaglandin-E Synthases - Abstract
Although both microsomal prostaglandin E synthase (mPGES)-1 and cyclooxygenase (COX)-2 are critical factors in stroke injury, but the interactions between these enzymes in the ischaemic brain is still obscure. This study examines the hypothesis that mPGES-1 activity is required for COX-2 to cause neuronal damage in ischaemic injury.We used a glutamate-induced excitotoxicity model in cultures of rat or mouse hippocampal slices and a mouse middle cerebral artery occlusion-reperfusion model in vivo. The effect of a COX-2 inhibitor on neuronal damage in mPGES-1 knockout (KO) mice was compared with that in wild-type (WT) mice.In rat hippocampal slices, glutamate-induced excitotoxicity, as well as prostaglandin (PG) E(2) production and PGES activation, was significantly attenuated by either MK-886 or NS-398, inhibitors of mPGES-1 and COX-2 respectively; however, co-application of these inhibitors had neither an additive nor a synergistic effect. The protective effect of NS-398 on the excitotoxicity observed in WT slices was completely abolished in mPGES-1 KO slices, which showed less excitotoxicity than WT slices. In the transient focal ischaemia model, mPGES-1 and COX-2 were co-localized in the infarct region of the cortex. Injection of NS-398 reduced not only ischaemic PGE(2) production, but also ischaemic injuries in WT mice, but not in mPGES-1 KO mice, which showed less dysfunction than WT mice.Microsomal prostaglandin E synthase-1 and COX-2 are co-induced by excess glutamate in ischaemic brain. These enzymes are co-localized and act together to exacerbate stroke injury, by excessive PGE(2) production.
- Published
- 2010
105. Time-Resolved Kerr Rotation Spectroscopy of Spin Dynamics in a Quantum Hall System
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D. Fukuoka, N. Tanaka, K. Oto, K. Muro, Y. Hirayama, N. Kumada, H. Yamaguchi, Marília Caldas, and Nelson Studart
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Physics ,Photoexcitation ,Kerr effect ,Condensed matter physics ,Hall effect ,Electron ,Landau quantization ,Atomic physics ,Quantum Hall effect ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Spectroscopy ,Excitation - Abstract
A Time‐resolved Kerr rotation spectroscopy under selective excitation by narrow spectrum pump beam is applied to high‐mobility two dimensional (2D) electrons. The large non‐oscillating Kerr signal is ascribed to the formation of Skyrmions by photoexcited carrier, and is confirmed by the selective excitation in TRKR measurement. The collapse of the spin coherence (dip of T2*) near ν = 1 may be related by the formation of Skyrmions and anti‐Skyrmiosn pair under photoexcitation.
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- 2010
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106. Experimental Proposal to Study β Decay Properties around N = 126 Nuclei Produced by Multi-Nucleon Transfer Reactions
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Y. X. Watanabe, H. Miyatake, S. C. Jeong, H. Ishiyama, N. Imai, Y. Hirayama, M. Oyaizu, K. Niki, M. Okada, Akira Ozawa, and Weiping Lu
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Nuclear physics ,Physics ,Nuclear reaction ,Decay scheme ,Isotopes of germanium ,Double beta decay ,Nuclear Theory ,Beta particle ,Isotopes of xenon ,Neutron ,Atomic physics ,Nuclear Experiment ,Radioactive decay - Abstract
The β decay properties of the neutron‐rich isotopes with neutron number N = 126, out of reach by any reaction well established so far, are very interesting from the astrophysical point of view. We will propose β decay lifetime measurements with a new isotope separation system, which is supposed to separate a single species of the radioactive nuclei among target‐like fragments produced via multi‐nucleon transfer reactions in binary heavy ion collisions, by using a gas catcher cell combined with laser resonance ionization technique. The present proposal aims to measure β decay properties of several nuclei around A∼200 with N = 126 and nearby nuclei by using a stable 136Xe beam on a 198Pt target.
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- 2010
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107. Development of the GEM-MSTPC for studies of astrophysical nuclear reaction rates
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K. Yamaguchi, H. Ishiyama, Y. Mizoi, Y. X. Watanabe, T. Hashimoto, M. H. Tanaka, H. Miyatake, Y. Hirayama, N. Imai, Y. Fuchi, S. C. Jeong, T. Nomura, S. K. Das, T. Fukuda, H. Makii, S. Mitsuoka, I. Arai, H. Yamaguchi, S. Kubono, Y. Wakabayashi, S. Hayakawa, Isao Tanihara, Hooi Jin Ong, Atsushi Tamii, Tadafumi Kishimoto, Toshitaka Kajino, Shigeru Kubono, and Tatsushi Shima
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Nuclear reaction ,Physics ,Physics::Instrumentation and Detectors ,Mixed gas ,Electrode ,Gas electron multiplier ,Injection rate ,Atomic physics ,Tracking (particle physics) ,Ion - Abstract
We have developed an active‐target type gas‐detector, a Gas Electron Multiplier Multiple‐Sampling and Tracking Proportional Chamber (GEM‐MSTPC) operating with low‐pressure He‐base mixed gas, where He is used as a target for studies of astrophysical nuclear reaction rates. Different kinds of 400 μm thick GEMs were examined. The gain stability was examined with a configuration of GEMs of 400 μm in thickness fabricated in different ways, against the injection rate of low‐energy heavy ions of 105 particles per second. The gain of GEM with Cu electrodes coated by Au was observed to be stable up to the injection rate of 105 particles per second.
- Published
- 2010
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108. Beta-NMR measurement of 58Cu in Si
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M. Mihara, T. Izumikawa, H. Ueno, K. Matsuta, D. Nishimura, T. Nagatomo, T. Moriguchi, Y. Ito, D. Nagae, M. Fukuda, A. Yoshimi, K. Yamada, M. Takechi, Y. Ichikawa, S. Momota, Y. Hirayama, T. Ohtsubo, S. Suzuki, T. Kubo, Y. Namiki, A. Ozawa, Y. Ishibashi, H. Oishi, K. Suzuki, I. Hachiuma, K. Namihira, D. Horikawa, T. Minamisono, T. Yamaguchi, T. Kuboki, T. Suzuki, K. Satoh, Y. Kobayashi, K. Asahi, K. Matsukawa, and K. Shirai
- Published
- 2010
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109. Low‐temperature transport characteristics of AlGaAs‐GaAs in‐plane‐gated wires
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Y. Hirayama, K. H. Ploog, and Andreas D. Wieck
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Ion implantation ,Depletion region ,Condensed matter physics ,law ,Chemistry ,Pinch ,General Physics and Astronomy ,Conductance ,Field-effect transistor ,Semiconductor device ,Resistor ,Fermi gas ,law.invention - Abstract
The transport characteristics of in‐plane‐gated wires, in which the conducting two‐dimensional electron gas (2DEG) channel and the 2DEG gates are separated by focused Ga‐ion‐beam scanned lines, are studied at low temperature (1.5 K). They are understood as a combination of the normal field‐effect‐transistor (FET) characteristics and a peculiar resistance jump at the channel pinch‐off threshold. In the normal FET region, the depletion region spreading is gradually controlled by a gate voltage applied to the in‐plane gates. The channel conductance variation by the gate voltage is explained by the change of the effective channel width rather than by the change of the carrier density. The variable range of the effective wire width is equal to or less than 0.6 μm in the experiments. In spite of this small controllable value, the channel can be pinched off up to W=10 μm with a gate leakage current of less than 1 nA. The pinch off of the wide wires always occurs together with a resistance jump at the threshold. ...
- Published
- 1992
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110. Parallel in-plane-gated wires coupled by a ballistic window
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Andreas D. Wieck, K. von Klitzing, Y. Hirayama, T. Bever, and K. H. Ploog
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Coupling ,In plane ,Charge transfer resistance ,Optics ,Materials science ,Electrical resistivity and conductivity ,business.industry ,Ballistic conduction ,Window (computing) ,Heterojunction ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,business ,Magnetic field - Abstract
Two parallel in-plane-gated (IPG) wires are coupled by a ballistic window. The ballistic window is rectangular, and the four terminals have a different arrangement from the usual fourfold-symmetry structures (such as a wire cross) where alternate terminals face each other. The ballistic coupling is achieved between two parallel wires by a sideways component but not by a straightforward component, and the four-terminal resistance (or transfer resistance) becomes negative at zero magnetic field. The amount of a sideways ballistic component is sensitive to a subband depopulation in each wire
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- 1992
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111. Magneto-optical study ofn-type modulation-dopedZnO/MgxZn1−xOsingle quantum well structures
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Y. Hirayama, Yusaburo Segawa, Y. Furuta, Yoshihiro Takagi, R. Shen, Takayuki Makino, Akira Ohtomo, Shojiro Takeyama, Atsushi Tsukazaki, and Masashi Kawasaki
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Photoluminescence ,Zeeman effect ,Materials science ,Condensed matter physics ,Exciton ,Electron ,Condensed Matter Physics ,Polarization (waves) ,Electronic, Optical and Magnetic Materials ,Blueshift ,Condensed Matter::Materials Science ,symbols.namesake ,symbols ,Quantum well ,Circular polarization - Abstract
We report on the effect of electron injection on the magneto-optical properties of MgZnO/ZnO(5 nm)/MgZnO single quantum wells (SQWs) by embedding a Ga delta-doped layer in one of the MgZnO barriers. Approaching the delta-doped layer to the SQW resulted in a photoluminescence (PL) blueshift due to the screening of internal polarization field by the injected electrons. Circular polarization in PL was enhanced by a magnetic field up to 50 T with a Faraday configuration. The observed Zeeman splitting and the degree of circular polarization in the magnetic field revealed that the PL originates from the negatively charged excitons ${X}^{\ensuremath{-}}$.
- Published
- 2009
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112. PRESENT STATUS OF CHARGE-BREEDING IN KEKCB AT TRIAC
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M. Oyaizu, S. C. Jeong, N. Imai, Y. Fuchi, Y. Hirayama, H. Ishiyama, H. Miyatake, M. Okada, Y. X. Watanabe, S. Ichikawa, H. Kabumoto, M. Matsuda, A. Osa, Y. Otokawa, Sun-Chan Jeong, Yutaka Utsuno, Tohru Motobayashi, and Angela Bracco
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Chemistry ,Cyclotron resonance ,TRIAC ,Particle accelerator ,Charge (physics) ,Electron cyclotron resonance ,Particle detector ,Ion source ,Ion ,law.invention ,Physics::Plasma Physics ,law ,Physics::Accelerator Physics ,Atomic physics - Abstract
We report a recent experiment about the measurement of wall distribution of ions externally injected for charge‐breeding in an electron cyclotron resonance (ECR) ion source. The ions, radioactive and singly charged 111In, were injected into the ECR ion source (ECRIS) for breeding their charge states at the Tokai Radioactive Ion Accelerator Complex (TRIAC). The residual radioactivity on the wall of the ECR plasma chamber of the source was measured, giving a two‐dimensional distribution of the ions failed to be re‐extracted during charge breeding. The distribution was decomposed, according to azimuthal symmetry, into three components, asymmetric, 120‐degree symmetric, and isotropic ones, whose origins were qualitatively discussed for clarifying ion‐losses in the course of charge breeding in ECRIS.
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- 2009
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113. Barrier distribution of quasi-elastic backward scattering
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S. Mitsuoka, H. Ikezoe, K. Nishio, Y. Watanabe, S. C. Jeong, H. Ishiyama, Y. Hirayama, N. Imai, H. Miyatake, Sun-Chan Jeong, Yutaka Utsuno, Tohru Motobayashi, and Angela Bracco
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Coupling ,symbols.namesake ,Cross section (physics) ,Chemistry ,Scattering ,Phonon ,Nuclear Theory ,Quadrupole ,symbols ,Rutherford scattering ,Atomic physics ,Excitation ,Cold fusion - Abstract
In order to study the nucleus‐nucleus interaction in Pb‐based cold fusion, we have measured excitation functions for quasi‐elastic scattering of 48Ti, 54Cr, 56Fe, 64Ni, 70Zn and 86Kr projectiles on 208Pb target at backward angles. The barrier distributions were derived from the first derivative of measured quasi‐elastic scattering cross sections relative to the Rutherford scattering cross section. The centroids of the barrier distributions show a deviation from several predicted barrier heights toward the low energy side. The shape of the barrier distributions is well reproduced by the results of a coupled‐channel calculation taking account of the coupling effects of two phonon excitations of the quadrupole vibration for the projectiles and of the octupole vibration for the 208Pb target.
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- 2009
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114. Measurement of quasi-elastic back-scattering of [sup 64]Ni+[sup 118]Sn and [sup 58]Ni+[sup 124]Sn
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Y. X. Watanabe, S. Mitsuoka, K. Nishio, S. C. Jeong, T. Hashimoto, Y. Hirayama, N. Imai, H. Ishiyama, H. Miyatake, H. Ikezoe, Sun-Chan Jeong, Yutaka Utsuno, Tohru Motobayashi, and Angela Bracco
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Physics ,Scattering ,Coulomb ,Quasiparticle ,Nuclear fusion ,Coulomb blockade ,Neutron ,Atomic physics ,Excitation ,Inelastic neutron scattering - Abstract
Two systems of 64Ni+118Sn and 58Ni+124Sn produce the same compound nucleus 182Pt in the fusion reaction and they show the similar fusion cross sections below and near the Coulomb barriers, although only the system of 58Ni+124Sn has positive Q‐value multi‐neutron transfer channels of 1–11 neutron(s). In order to investigate the possible effect of positive Q‐value multi‐neutron transfer channels on the capture cross sections, the quasi‐elastic back‐scattering for the two systems were measured below and near the Coulomb barriers at the backward angles of 162° and 172°. The beam energies were altered in the energy range and the quasi‐elastic back‐scattering excitation functions were obtained. They were compared with the coupled‐channel calculations of collective excitations and a two‐neutron transfer channel, indicating no evidence of a significant effect of the positive Q‐value multi‐neutron transfer channels on the capture cross sections for the system of 58Ni+124Sn.
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- 2009
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115. Magnetic Properties of Mn-Al Multilayered Films
- Author
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Masaaki Futamoto, Teruaki Takeuchi, and Y. Hirayama
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Multiple layer ,Magnetization ,Materials science ,Ferromagnetism ,Condensed matter physics ,Crystal chemistry ,Magnetic films ,Magnetic force microscope ,Magnetic hysteresis ,Microstructure - Published
- 1991
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116. The Impact of the Minkatsu Policy on Japanese Housing and Land Use
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K Hayakawa and Y Hirayama
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Government ,Land use ,Public housing ,Economic policy ,media_common.quotation_subject ,Geography, Planning and Development ,Real estate ,Environmental Science (miscellaneous) ,Recession ,Deregulation ,Economy ,Right to housing ,Economics ,Zoning ,media_common - Abstract
During the period 1983–87, the ‘ minkatsu’ policy of the former Nakasone Government caused many serious problems. Urban land became a target of direct speculation by real estate companies, banks, and big enterprises. This phenomenon began in Tokyo and has now spread to all the nation's large cities. A new housing crisis has resulted, and the right to housing is widely threatened. We discuss, in this paper, the relationship of minkatsu, to the deregulation of zoning, the sale of nationally and publicly owned lands, the unease of residents, the recession in public housing policy, and skyrocketing land prices.
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- 1991
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117. A case of small cell carcinoma in the buccal region
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Kazuhide Nishihara, Etsuro Nozoe, Akihiko Miyawaki, Ichiro Semba, Norifumi Nakamura, and Y. Hirayama
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Male ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,Enolase ,Small-cell carcinoma ,Metastasis ,Cytokeratin ,Fatal Outcome ,Biomarkers, Tumor ,Medicine ,Humans ,Carcinoma, Small Cell ,Aged, 80 and over ,Chemotherapy ,biology ,business.industry ,Mouth Mucosa ,Cancer ,medicine.disease ,Combined Modality Therapy ,Peptide Fragments ,Recombinant Proteins ,Radiation therapy ,stomatognathic diseases ,Cheek ,Otorhinolaryngology ,Phosphopyruvate Hydratase ,biology.protein ,Surgery ,Vitronectin ,Mouth Neoplasms ,Oral Surgery ,business - Abstract
Small cell carcinoma (SCC) in the head and neck region is an extremely rare high-grade malignant tumor. The authors report a case of an SCC occurring in the left buccal region. An 85-year-old man exhibited left cheek swelling that rapidly increased in size. Histopathological examination revealed invasive growth of an SCC into the musculo-adipose tissue. Immunohistochemically, the tumor cells were positive for cytokeratin (AE1/AE3), neuron-specific enolase (NSE) and CD56, but negative for cytokeratin 20. The patient received chemotherapy and radiotherapy, which resulted in marked regression of the tumor. Surgical resection was performed. The serum levels of NSE and pro-gastrin-releasing peptide (pro-GRP) increased and multiple metastases of the tumor occurred 1 month after surgery. SCCs tend to exhibit aggressive invasion and metastasis so chemotherapy for the whole body is recommended to prevent dissemination of the tumor cells. Serum levels of NSE and pro-GRP are considered to be useful tumor markers for understanding the status of the tumor and the clinical symptoms.
- Published
- 2008
118. Trefftz analysis for temperature rise on human skin exposed to electromagnetic waves
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Y. Hirayama and E. Kita
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Polynomial ,Simple (abstract algebra) ,law ,Homogeneous differential equation ,Trefftz method ,Mathematical analysis ,Cartesian coordinate system ,Function (mathematics) ,Poisson's equation ,Electromagnetic radiation ,Mathematics ,law.invention - Abstract
This paper describes the application of Trefftz method to the temperature rise in a human skin exposed to a radiation from a cellular phone. A governing equation is given as Poisson equation. An inhomogeneous term of the equation is approximated with a polynomial function in Cartesian coordinates. The use of the approximated term transforms the original boundary-value problem to that governed with a homogeneous differential equation. The transformed problem can be solved by the traditional Trefftz formulation. Firstly, the present method is applied to a simple numerical example in order to confirm the formulation. The temperature rise in a skin exposed to a radiation is considered as a second example.
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- 2008
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119. Direct measurement of [sup 8]Li+d reactions of astrophysical interest
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T. Hashimoto, H. Ishiyama, Y. X. Watanabe, Y. Hirayama, N. Imai, H. Miyatake, S. C. Jeong, M.-H. Tanaka, N. Yoshikawa, T. Nomura, S. Mitsuoka, K. Nishio, T. K. Sato, S. Ichikawa, H. Ikezoe, A. Osa, M. Matsuda, S. K. Das, Y. Mizoi, T. Fukuda, A. Sato, T. Shimoda, Takuma Suda, Takaya Nozawa, Akira Ohnishi, Kiyoshi Kato, Masayuki Y. Fujimoto, Toshitaka Kajino, and Shigeru Kubono
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Physics ,Reaction rate ,Work (thermodynamics) ,Big Bang nucleosynthesis ,Nucleosynthesis ,Isotopes of lithium ,Atomic physics ,Excitation ,Order of magnitude ,Beam (structure) - Abstract
The excitation functions of the 8Li(d,t)7Li and the 8Li(d,p)9Li reactions were directly measured using 8Li beams with Ecm = 0.3, 0.4, 0.5, 0.7, 0.8, 1.0, 1.1, and 1.2 MeV irradiating CD2 targets. These beam energies covered the Gamow peaks for 1−3×109 K. Large cross sections were observed at around Ecm = 0.8 MeV for the 8Li(d,t)7Li and Ecm = 1.0 MeV for the 8Li(d,p)9Li, implying the existence of a resonant state of 10Be at the excitation energy of around 22.4 MeV. Enhanced with the present work, the astrophysical reaction rates of the 8Li(d,t)7Li and the 8Li(d,p)9Li reactions are higher by one and two orders of magnitude than the previously evaluated ones, respectively.
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- 2008
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120. Detection of quantitative trait loci controlling extremely early heading in rice
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Yasunori Nonoue, Shaoyang Lin, Masahiro Yano, Y. Hirayama, Kenji Fujino, and Utako Yamanouchi
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Genetics ,Oryza sativa ,Time Factors ,biology ,Genotype ,Quantitative Trait Loci ,Epistasis, Genetic ,Oryza ,General Medicine ,Flowers ,Sequence Analysis, DNA ,Quantitative trait locus ,biology.organism_classification ,Japonica ,Qtl analysis ,Plant biochemistry ,F2 population ,Epistasis ,Allele ,Agronomy and Crop Science ,Crosses, Genetic ,Genome, Plant ,Biotechnology - Abstract
To clarify the genetic basis of extremely early heading in rice, we conducted quantitative trait locus (QTL) analyses using F2 populations from two genetically wide cross combinations, Hayamasari/Kasalath (HaF2) and Hoshinoyume/Kasalath (HoF2). Hayamasari and Hoshinoyume are extremely early-heading japonica cultivars. Photoperiod sensitivity is completely lost in Hayamasari and weak in Hoshinoyume. Three QTLs, QTL(chr6), QTL(chr7), and QTL(chr8), for days-to-heading (DTH) in HaF2 were detected on chromosomes 6, 7, and 8, respectively, and QTL(chr6) and QTL(chr7) were detected in HoF2. On the basis of the chromosomal locations, QTL(chr6), QTL(chr7), and QTL(chr8) may be likely to be Hd1, Hd4, and Hd5, respectively, which had been detected previously as QTLs for DTH in an F2 population of Nipponbare × Kasalath. Alleles of QTL(chr7) decreased DTH dramatically in both Hayamasari and Hoshinoyume, suggesting that QTL(chr7) has a major role in determining extremely early heading. In addition, allele-specific interactions were detected between QTL(chr6), QTL(chr7) and QTL(chr8). This result suggests that not only allelic differences but also epistatic interactions contribute to extremely early heading. QTL(chr8) was detected in HaF2, but not in HoF2, suggesting that it determines the difference in DTH between Hayamasari and Hoshinoyume. A major QTL was also detected in the region of QTL(chr8) in QTL analysis using an F2 population of Hayamasari × Hoshinoyume. This result supports the idea that QTL(chr8) is a major factor that determines the difference in DTH between Hayamasari and Hoshinoyume, and is involved in photoperiod sensitivity.
- Published
- 2007
121. POLARIZED 11<font>LI</font> BEAM AT TRIUMF AND ITS APPLICATION FOR SPECTROSCOPIC STUDY OF THE DAUGHTER NUCLEUS 11<font>BE</font>
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Y. Yano, K.P. Jackson, Y. Hirayama, H. Miyatake, K. Kawai, M. Yagi, Y. Akasaka, I. Wakabayashi, A. Hatakeyama, Tadashi Shimoda, C. D. P. Levy, and H. Izumi
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Physics ,Nuclear physics ,medicine.anatomical_structure ,medicine ,Atomic physics ,Nucleus ,Beam (structure) - Published
- 2007
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122. Growth of InAs Channel HEMT Structure on Si substrate and It's Possible Application for Low Power Logic
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Y. Lin, M. Ueki, Y. Hirayama, Chun-Yen Chang, Hiroshi Yamaguchi, and Edward Yi Chang
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Materials science ,Si substrate ,business.industry ,Optoelectronics ,Nanotechnology ,High-electron-mobility transistor ,business ,Communication channel ,Power (physics) - Published
- 2007
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123. Status of Tokai Radioactive Ion Accelerator Complex and Feasibility Study for Transfer Reactions Using Low-Energy RNB
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N. Imai, A. Arai, Y. Arakaki, Y. Fuchi, Y. Hirayama, H. Ishiyama, S. C. Jeong, H. Kawakami, H. Miyatake, K. Niki, T. Nomura, M. Okada, M. Oyaizu, M. H. Tanaka, M. Tomizawa, Y. X. Watanabe, Y. Yoshikawa, S. Abe, S. Hanashima, T. Hashimoto, S. Ichikawa, H. Ikezoe, T. Ishii, N. Ishizaki, H. Kabumoto, I. Katayama, M. Koizumi, M. Matuda, S. Mitsuoka, T. Nakanoya, K. Nishio, I. Ohuchi, S. Osa, T. K. Sato, S. Takeuchi, H. Tayama, Y. Tsukihashi, H. Bhang, S. Choi, Y. M. Oh, J. S. Song, K. H. Tshoo, J. H. Ha, Y. K. Kim, S. H. Park, Yu. E. Penionzhkevich, and E. A. Cherepanov
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Radioactive ion beams ,Chemistry ,Fission ,Isotope separation ,law.invention ,Ion ,Nuclear physics ,Low energy ,law ,High energy accelerator ,Physics::Accelerator Physics ,Nuclear Experiment ,Nucleon ,Beam (structure) - Abstract
An ISOL‐based radioactive nuclear beam facility, Tokai Radioactive Ion Accelerator Complex (TRIAC), has been jointly constructed by High Energy Accelerator Research Organization (KEK) and Japan Atomic Energy Agency (JAEA). The facility started to provide RNBs for experiments in 2005. RNBs, including fission fragments with energies up to 1.1 MeV/nucleon, are available. The experiments were performed with accelerated 8Li beams of various energies. Current status of the equipments and preliminary results on these experimental studies are presented.
- Published
- 2007
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124. BOTULINUM TOXIN TYPE A THERAPY FOR CERVICAL DYSTONIA IN SEVERE CEREBRAL PALSY
- Author
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S. Sone, H. Suzuki, Y. Hirayama, H. Saijo, M. Izumi, H. Hamaguchi, and K. Araki
- Subjects
medicine.medical_specialty ,business.industry ,Anesthesia ,Pediatrics, Perinatology and Child Health ,Medicine ,Neurology (clinical) ,General Medicine ,Cervical dystonia ,business ,medicine.disease ,Surgery ,Cerebral palsy ,Botulinum toxin type - Published
- 2006
- Full Text
- View/download PDF
125. P149 Risk factors for post-colectomy complications in patients with ulcerative colitis
- Author
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H. Goto, K. Morise, K. Funasaka, K. Ishiguro, O. Maeda, M. Matsushita, Y. Hirayama, K. Furukawa, K. Maeda, T. Ando, R. Miyahara, M. Nakamura, and O. Watanabe
- Subjects
medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Internal medicine ,Gastroenterology ,Medicine ,In patient ,General Medicine ,business ,medicine.disease ,Ulcerative colitis ,Colectomy - Published
- 2014
- Full Text
- View/download PDF
126. Low noise performance of CoCrPt single-layer perpendicular magnetic recording media
- Author
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Y. Hirayama, Y. Honda, A. Kikukawa, and M. Futamoto
- Published
- 2005
- Full Text
- View/download PDF
127. Feasibility Study On Perpendicular Magnetic Recording For Maintaining Areal Density Growth Beyond 10 Gb/in/sup 2
- Author
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M. Umemoto, K. Itch, Y. Hirayama, Masaaki Futamoto, Yoshinori Honda, and K. Yoshida
- Subjects
Optics ,Materials science ,Condensed matter physics ,Magnetoresistance ,business.industry ,Perpendicular ,Area density ,Magnetic force microscope ,business - Published
- 2005
- Full Text
- View/download PDF
128. Microscopic Noise And Signal Characteristics Of Perpendicular Recording Media Studied By Magnetic Force Microscopy
- Author
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Y. Honda, Y. Hirayama, K. Itou, and M. Futamoto
- Published
- 2005
- Full Text
- View/download PDF
129. Involvement of transforming growth factor-beta and thrombopoietin in the pathogenesis of myelodysplastic syndrome with myelofibrosis
- Author
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Tetsuji Takayama, N Yamauchi, Hiroyuki Kuroda, Kyuhei Kohda, Takuya Matsunaga, Ikuta Tanaka, T. Sato, Koji Miyanishi, Takehide Akiyama, Yoshiro Niitsu, Y Hirayama, Junji Kato, S Sakamaki, Takeshi Terui, R. Takimoto, and K Kogawa
- Subjects
Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Pathology ,CD34 ,Antigens, CD34 ,Bone Marrow Cells ,Cell Count ,Enzyme-Linked Immunosorbent Assay ,Peripheral blood mononuclear cell ,Transforming Growth Factor beta ,hemic and lymphatic diseases ,Internal medicine ,medicine ,Humans ,RNA, Messenger ,Myelofibrosis ,Thrombopoietin ,Aged ,Aged, 80 and over ,Hematology ,business.industry ,Essential thrombocythemia ,Middle Aged ,medicine.disease ,Thrombocytopenic purpura ,medicine.anatomical_structure ,Endocrinology ,Oncology ,Primary Myelofibrosis ,Myelodysplastic Syndromes ,Leukocytes, Mononuclear ,Female ,Bone marrow ,business ,Megakaryocytes - Abstract
We investigated the cause of myelofibrosis and proliferation of megakaryocytes in myelodysplastic syndrome with myelofibrosis (MDS-MF (+)). Plasma-transforming growth factor-beta1 (PTGF-beta1) concentrations closely correlated with myelofibrosis grade in MDS-MF (+) and were higher than those in idiopathic myelofibrosis (IMF), essential thrombocythemia (ET), idiopathic thrombocytopenic purpura (ITP), MDS-without MF (MDS-MF (-)) or healthy volunteers (HV). Peripheral blood mononuclear cells from MDS-MF (+) patients expressed more TGF-beta1 mRNA than those from IMF, MDS-MF (-) or HV. When we immunostained bone marrow specimens of MDS-MF (+) for TGF-beta, the intensity of blasts was apparently higher than that of megakaryocytes, while in MDS-MF (-), megakaryocytes were immunostained with a similar intensity as that in MDS-MF (+), but blasts were negative for staining. In IMF, megakaryocytes, monocytes and small mononuclear cells representing CD34+ cells were all similarly stained with a much lower intensity than that of blasts in MDS-MF (+). The number of bone marrow megakaryocytes were increased the most in MDS-MF (+), followed by ET, ITP, MDS-MF (-) and NHL and correlated with plasma thrombopoietin (TPO) levels or with plasma TGF-beta1 levels, respectively, in each disease. Thus, in MDS-MF (+), both myelofibrosis and the increased megakaryocytes were ascribed to overproduction of TGF-beta1 from blasts.
- Published
- 2005
130. Heat-affected zone measurement of copper ablated with femtosecond laser pulses
- Author
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Y. Hirayama and Minoru Obara
- Subjects
Amorphous metal ,Argon ,Laser ablation ,Materials science ,Analytical chemistry ,chemistry.chemical_element ,Laser ,eye diseases ,law.invention ,Amorphous solid ,chemistry ,law ,Etching (microfabrication) ,Femtosecond ,Sapphire ,sense organs - Abstract
In this paper, we would like to report on the heat-affected zone of metallic bulk crystal of Cu ablated with femtosecond Ti:sapphire laser. Due to the heat effects induced by laser pulses, the ablated bottom area is partially converted into the amorphous metals from the crystalline metals. The laser-ablated area etched using argon ion etching apparatus is measured by XRD.
- Published
- 2005
- Full Text
- View/download PDF
131. Community partition based chat system easy to join for new members
- Author
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K. Gyohten and Y. Hirayama
- Subjects
World Wide Web ,business.industry ,Computer science ,media_common.quotation_subject ,Partition (politics) ,Join (sigma algebra) ,Chat room ,The Internet ,Conversation ,business ,media_common - Abstract
In a chat system, an increase of the participants leads to confusion of topics and makes it difficult to continue an orderly conversation. Moreover, senior participants tend to be familiar with each other and form a so-called community. This behavior of the senior users consequently makes newcomers hard to participate in the existing rooms. To cope with these problems, this paper proposes a community partition based chat system which divides overcrowded rooms to keep the proper number of participants. The system frequently estimates relationship between participants and separates the community members from the chat room. The separated members thus can continue to communicate with each other in another room newly generated, while the remained participants unacquainted with each other can make a beginning of the conversation. We had made an evaluation experiment on the proposed chat system and could obtain results which agree with the aim of our research
- Published
- 2005
- Full Text
- View/download PDF
132. Transistors
- Author
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Y. Hirayama
- Published
- 2005
- Full Text
- View/download PDF
133. Heat-affected zone evaluation of copper and iron metals induced by femtosecond laser ablation
- Author
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Y. Hirayama and Minoru Obara
- Subjects
Heat-affected zone ,Materials science ,Laser ablation ,business.industry ,chemistry.chemical_element ,Laser ,Femtosecond laser ablation ,Copper ,law.invention ,chemistry ,law ,Sapphire ,Optoelectronics ,business ,Titanium - Abstract
In this paper, we would like to report on the heat-affected zone measurement of copper and iron bulk metals ablated with 100 fs Ti:sapphire laser pulses. The thickness of the heat-affected zone in the bottom area ablated is evaluated.
- Published
- 2004
- Full Text
- View/download PDF
134. Mechanism of PFC reduction with gas circulation RIE system
- Author
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Y. Nagata and Y. Hirayama
- Subjects
Reduction (complexity) ,Materials science ,Circulation (fluid dynamics) ,Control theory ,Mechanism (sociology) - Published
- 2004
- Full Text
- View/download PDF
135. Ultra-thin intermediate template layer for perpendicular recording media
- Author
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Y. Hirayama, I. Tamai, I. Takekuma, and Y. Hosoe
- Published
- 2004
- Full Text
- View/download PDF
136. Ultra-high differential gain in GaInAs-AlGaInAs quantum wells: experiment and modeling
- Author
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Y. Hirayama, Hitoshi Shimizu, Jimmy Xu, G.L. Tan, M.L. Xu, Toru Fukushima, R.S. Mand, and M. Irikawa
- Subjects
Materials science ,Differential gain ,business.industry ,Material system ,Epitaxy ,Laser ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Gallium arsenide ,law.invention ,chemistry.chemical_compound ,Optics ,chemistry ,Quantum dot laser ,law ,Optoelectronics ,Semiconductor optical gain ,Electrical and Electronic Engineering ,business ,Quantum well - Abstract
A high differential gain of 9.3/spl times/10/sup -16/ cm/sup 2/ is obtained in GaInAs-AlGaInAs 1.55-/spl mu/m multiquantum-well lasers with 1% compressive strain grown by molecular-beam epitaxy. This is the highest ever achieved in this material system. The model-solid theory and an approximate k.p method are incorporated in the theoretical gain calculation that provides a detailed understanding of the experimental results and guidance to further improvement. >
- Published
- 1995
- Full Text
- View/download PDF
137. Comparison of effective /spl alpha/ parameters for multiquantum-well electroabsorption modulators
- Author
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N. Suzuki and Y. Hirayama
- Subjects
Physics ,Imagination ,Chemical substance ,business.industry ,Exciton ,media_common.quotation_subject ,Computer Science::Software Engineering ,Alpha (ethology) ,Transmission performance ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Wavelength ,Light source ,Optoelectronics ,Electrical and Electronic Engineering ,business ,Voltage ,media_common - Abstract
A new effective /spl alpha/ parameter appropriate for evaluating the transmission performance of multiquantum-well electroabsorption (MQW-EA) modulators is proposed. It is defined by the ratio of the phase change to the loss change between the ON voltage and the voltage at which the exciton peak reaches the wavelength of the light source. Simulation reveals that along various effective /spl alpha/ parameters it has the best correlation with the equivalent /spl alpha/ parameter obtained from the transmission performance. >
- Published
- 1995
- Full Text
- View/download PDF
138. Carrier confinement by multiple quantum barriers in 1.55 μm strained GaInAs/AlGaInAs quantum well lasers
- Author
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Y. Hirayama, Kazuaki Nishikata, Michinori Irikawa, Hitoshi Shimizu, and T. Fukushima
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,Multiple quantum ,Slope efficiency ,Carrier lifetime ,Laser ,Semiconductor laser theory ,law.invention ,law ,Optoelectronics ,Spontaneous emission ,business ,Quantum well ,Molecular beam epitaxy - Abstract
Carrier confinement performance by multiple quantum barriers (MQB) is demonstrated in 1.55 μm strained GaInAs/AlGaInAs multiple quantum well (MQW) lasers grown by molecular beam epitaxy. The strained MQW lasers with MQB at p‐side optical confinement layer show larger characteristic temperature and slope efficiency at high temperature than those without MQB. It is also shown that the MQW lasers with MQB have less spontaneous emission from the optical confinement layer than the lasers without MQB. As another important result, it is demonstrated for the first time that the MQW lasers with MQB have less dependency of the K factor on the temperature than the lasers without MQB. These results further verify the effective carrier confinement performance of GaInAs/AlInAs MQB structure.
- Published
- 1995
- Full Text
- View/download PDF
139. The new beta-NMR facility at TRIUMF and applications in semiconductors
- Author
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S. R. Kreitzman, R. F. Kiefl, G.D. Morris, Jak Chakhalian, Y. Hirayama, Richard Baartman, S. Daviel, W. A. MacFarlane, Zaher Salman, Kim H. Chow, Donald J. Arseneau, Atsushi Hatakeyama, E. Reynard, R. Poutissou, Bassam Hitti, P. Amaudruz, and C. D. P. Levy
- Subjects
Radioactive ion beams ,Materials science ,Meson ,business.industry ,Semiconductor materials ,Cyclotron ,Resonance ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,law.invention ,Nuclear physics ,Semiconductor ,Nuclear magnetic resonance ,law ,Electrical and Electronic Engineering ,business - Abstract
A new facililty for conducting beta-detected nuclear magnetic resonance (beta-NMR) investigations of condensed matter systems has recently been constucted at TriUniversity Meson Facility in Vancouver, Canada. The unique features of this new facility are described, and some preliminary results on Li-8(+) in GaAs are presented. (C) 2003 Elsevier B.V. All rights reserved.
- Published
- 2003
140. A CPU on a glass substrate using CG-silicon TFTs
- Author
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K. Mutaguch, M. Katayama, T. Ozaki, Yasushi Kubota, Shigeki Imai, K. Kato, A. Imaya, Y. Hirayama, A. Ishikawa, T. Ikeda, B. Lee, Shunpei Yamazaki, and Y. Kurokawa
- Subjects
Materials science ,Silicon ,chemistry ,business.industry ,Thin-film transistor ,Distortion ,Electrical engineering ,Optoelectronics ,chemistry.chemical_element ,Integrated circuit packaging ,Substrate (electronics) ,business ,Chip - Abstract
A CPU is produced on a glass substrate using continuous-gain silicon TFTs. Corning 1737 glass with a distortion point of 640/spl deg/C forms the glass substrate and the process temperature never exceeds 550/spl deg/C. The 8b CPU contains 13,000 TFTs and the chip area is 13/spl times/13mm/sup 2/. Operation at a frequency of 3MHz was confirmed at 5V.
- Published
- 2003
- Full Text
- View/download PDF
141. Balanced electron drift oxide etcher with Xe added gas chemistry for low cost and high performance contact metallization
- Author
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M. Hirayama, H. Komeda, Y. Hirayama, Kazuhide Ino, R. Kaihara, and Tadahiro Ohmi
- Subjects
Materials science ,Ion implantation ,Dopant ,Etching ,Electrode ,Contact resistance ,Cavity magnetron ,Analytical chemistry ,Wafer ,Ion - Abstract
A new plasma source called balanced electron drift (BED) magnetron plasma was developed for SiO/sub 2/ contact/via hole etching. E/spl times/B drift of electrons, which is notorious for degrading the uniformity of magnetron plasmas (Sekine et al, 1995), has been completely balanced by applying appropriate 100 MHz RF power to the upper ring electrode. As a result, highly uniform self bias voltage (/spl Delta/V/sub DC/
- Published
- 2003
- Full Text
- View/download PDF
142. The data transmission system for the real-time seafloor monitoring cable network
- Author
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Y. Hirayama and M. Yoshida
- Subjects
Data transmission systems ,Engineering ,Transmission (telecommunications) ,business.industry ,Power consumption ,Range (aeronautics) ,Electrical engineering ,Cable network ,Construct (python library) ,business ,Seabed ,Seafloor spreading - Abstract
The ARENA (advanced real-time earth monitoring network in the area) project has been proposed by JAMSTEC. The data transmission system for seafloor monitoring cable network has been discussed in the transmission sub-workgroup of ARENA project. The paper reports the results of discussions in the sub-workgroup. In the ARENA project, the total length of cable is more than 1000 km, and observation nodes are set at about 50 km intervals, with various sensors installed in these nodes. The objective is to construct the data transmission system from the sensors in the seafloor to the landing stations. Various conditions should be considered such as transmission range, time accuracy, extendibility, cost, affinity with IP, power consumption.
- Published
- 2003
- Full Text
- View/download PDF
143. A block segmentation method for document images with complicated column structures
- Author
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Y. Hirayama
- Subjects
Column (typography) ,Computer science ,Block (programming) ,business.industry ,Character (computing) ,Process (computing) ,Scale-space segmentation ,Segmentation ,Computer vision ,Image segmentation ,Artificial intelligence ,business ,Projection (set theory) - Abstract
Presents a novel block segmentation method for document images which can be applied to various document formats. Some documents have complicated column structures, in which some figure areas have no surrounding rectangles and others cut across text areas. In the approach presented, in order to segment documents into text and figure areas, the text areas are analyzed first, and the figure areas are then detected by analyzing information on the text areas. The overall process is as follows. First, character strings are merged into text groups by analyzing regularity in the text areas. Next, border lines of columns are detected by linking the edges of the text groups. After that, the whole page is segmented into small blocks according to the border lines. The blocks are then unified by using the column information, and some unified blocks are detected. Finally, a projection profile method is applied to the unified blocks in order to detect text areas and figure areas. This method was applied to 61 pages of Japanese technical papers and magazines, and 93.3% of the text areas and 93.2% of the figure areas were detected correctly. >
- Published
- 2002
- Full Text
- View/download PDF
144. Application of generalized stochastic Petri net to quantitative evaluation of software process
- Author
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Y. Hirayama, Shinji Kusumoto, Tohru Kikuno, and Osamu Mizuno
- Subjects
Computer science ,business.industry ,Software development ,Petri net ,computer.software_genre ,Software metric ,Software framework ,Software development process ,Software ,Software sizing ,Software deployment ,Goal-Driven Software Development Process ,Software construction ,Stochastic Petri net ,Software design ,Software system ,Software verification and validation ,Project management ,business ,Software engineering ,computer ,Software project management ,Software design description - Abstract
As the complexity and size of software increases, project management becomes important to develop reliable software cost-effectively within specified time constraints. In order to manage a software project effectively, it is necessary to establish a control method based on the objective and quantitative evaluation data on the current status of the software project. Furusawa (1994) presented quantitative evaluations of the software development process described by a generalized stochastic Petri net. However, the evaluation in the above paper cannot deal with the development period sufficiently because of restrictions on the GSPN model. This paper defines a new hierarchical model for software projects by extending the previous GSPN model and by introducing the concept of workload, and proposes a method to evaluate the software process from the viewpoints of the quality, cost and delivery date. As a result, the new model can take the influence of human factors into account, and thus can evaluate the dynamic aspects of software projects. Finally, the results of a case study of the proposed method provide us with some implications on software project management.
- Published
- 2002
- Full Text
- View/download PDF
145. 1.55 μm strained GaInAs/AlGaInAs MQW lasers with a multi-quantum barrier
- Author
-
Michinori Irikawa, Kazuaki Nishikata, Y. Hirayama, T. Fukushima, and H. Shimizu
- Subjects
Waveguide lasers ,Threshold current ,Materials science ,business.industry ,Carrier leakage ,Laser ,law.invention ,Gallium arsenide ,chemistry.chemical_compound ,Molecular beam epitaxial growth ,chemistry ,law ,Optoelectronics ,Spontaneous emission ,business ,Quantum - Abstract
The authors have fabricated 1.55 /spl mu/m strained GaInAs/AlGaInAs MQW lasers with a multiquantum barrier (MQB). A reduction of carrier leakage upon incorporation of the MQB structure was demonstrated experimentally in long-wavelength lasers for the first time.
- Published
- 2002
- Full Text
- View/download PDF
146. Personal identification system through facial images based on the modified HSV color system and isodensity maps
- Author
-
O. Nakamura and Y. Hirayama
- Subjects
Identification (information) ,Computer science ,business.industry ,Face (geometry) ,Stability (learning theory) ,Computer vision ,HSL and HSV ,Artificial intelligence ,business ,Facial recognition system ,Identification system - Abstract
An algorithm which evaluates the extraction accuracy of a facial area and a personal identification system which is able to apply the facial image changes are described. Computer simulation using 91 pictures for extracting facial area shows a correct extraction accuracy of 90.1%. The experimental results using 79 pairs of mobile faces show a correct identification accuracy of 84.8%.
- Published
- 2002
- Full Text
- View/download PDF
147. Splenic marginal zone lymphoma presenting as myelofibrosis associated with bone marrow involvement of lymphoma cells which secrete a large amount of TGF-beta
- Author
-
Toshinori Okuda, Naofumi Takemoto, Hiroyuki Nagashima, N Ohmi, Y. Hirayama, Takuya Matsunaga, Yasuaki Tamura, Takeshi Terui, T. Sato, N Miyajima, H Sasaki, and Yoshiro Niitsu
- Subjects
medicine.medical_specialty ,Pathology ,Lymphoma ,Splenic Neoplasm ,Spleen ,Bone Marrow Cells ,Fibrosis ,Transforming Growth Factor beta ,hemic and lymphatic diseases ,Internal medicine ,medicine ,Humans ,Splenic marginal zone lymphoma ,Myelofibrosis ,Aged ,Hematology ,business.industry ,Splenic Neoplasms ,General Medicine ,medicine.disease ,Immunohistochemistry ,medicine.anatomical_structure ,Primary Myelofibrosis ,Female ,Bone marrow ,business - Abstract
We report here on a patient with splenic marginal zone lymphoma presenting diffuse fibrosis of bone marrow and spleen. After splenectomy and chemotherapy, bone marrow biopsy demonstrated an improvement of fibrosis. Plasma concentration of transforming growth factor (TGF)-beta was much higher in this patient than in those of age-matched non-Hodgkin's lymphoma patients ( n=5) at diagnosis, decreasing after resolution of myelofibrosis. Immunostaining with the TGF-beta antibody revealed that the lymphoma cells in bone marrow and spleen were positive for TGF-beta. TGF-beta secreted by tumor cells was thought to stimulate the growth of fibroblasts and synthesize collagen in bone marrow and splenic fibroblasts, and play an important role in the development of marrow and splenic fibrosis in this patient. This is the first report of a patient with splenic marginal zone lymphoma presenting as myelofibrosis associated with bone marrow involvement of lymphoma cells which secrete a large amount of TGF-beta.
- Published
- 2002
148. A method for table structure analysis using DP matching
- Author
-
Y. Hirayama
- Subjects
Matching (statistics) ,Information retrieval ,Character (computing) ,Computer science ,Table (database) ,Column (database) ,Row - Abstract
This paper presents a novel method for table structure analysis. Many documents have table areas, and some have both table and figure areas. It is very important to be able to classify table and figure areas automatically. Furthermore, in tables, the column and row in which a character string is located are very important pieces of information. To detect and analyze table areas, the following method is applied: First, areas that may contain tables or figures are distinguished from text areas by the presence of horizontal and vertical lines. Next, the areas are assumed to be table areas and are analyzed as such. A judgment is made on whether each of the areas can in fact be a table area or not; in this way, the actual table areas are detected. Finally, the structures of the areas are analyzed and character strings in the areas are arranged by using the DP matching method. This method was applied to sixty-five pages of Japanese technical papers, magazines, manuals for software programs, and pages including 34 table areas, 48 line drawing areas, and 35 image areas. As a result, 96.6 percent of the areas were detected correctly and 91.7 percent of the tables were analyzed and arranged correctly.
- Published
- 2002
- Full Text
- View/download PDF
149. Approach for environmental standard with etch tools
- Author
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Y. Hirayama, K. Fukasawa, T. Kitoku, A. Kobayashi, M. Saito, and K. Nagaseki
- Subjects
Chiller ,chemistry.chemical_classification ,chemistry.chemical_compound ,Waste management ,chemistry ,Electric potential energy ,Carbon dioxide ,Water cooling ,chemistry.chemical_element ,Refrigeration ,Compounds of carbon ,Electric power ,Nitrogen - Abstract
In order to reduce electrical power usage and the consumption of PFCs, we have researched three kinds of techniques. The first is intermittent operation of dry pumps. The next is chiller with a new refrigeration system. The technique is a gas circulation system. The first technique, intermittent pump operation, results in 51.6% reduction in carbon dioxide to be emitted for the use of energy, which includes electrical energy, nitrogen and cooling water. Next, the new Chiller conserves 68% of the electrical energy at maximum. The gas circulation system can mark 50-70% reduction in the usage of process gases, and this leads to approximately 75% reduction in PFCs emissions.
- Published
- 2002
- Full Text
- View/download PDF
150. Compound Semiconductors 2001
- Author
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Yasuhiko Arakawa, K Kishino, H Yamaguchi, and Y. Hirayama
- Subjects
Materials science ,Compound semiconductor ,Physical chemistry - Published
- 2002
- Full Text
- View/download PDF
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