17,737 results on '"I Yamamoto"'
Search Results
52. Brain-Derived Neurotrophic Factor Treatment Increases the Skeletal Muscle Glucose Transporter 4 Protein Expression in Mice
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Haruka Sasaki, Hiroshi Nakano, Zsolt Radak, K. I. Yamamoto, Shuzo Kumagai, and Masataka Suwa
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medicine.medical_specialty ,Time Factors ,Physiology ,Injections, Subcutaneous ,Weight Gain ,Eating ,Mice ,Gastrocnemius muscle ,Downregulation and upregulation ,Neurotrophic factors ,Internal medicine ,medicine ,Animals ,Glycolysis ,Muscle, Skeletal ,Brain-derived neurotrophic factor ,Mice, Inbred ICR ,Glucose Transporter Type 4 ,biology ,Brain-Derived Neurotrophic Factor ,Glucose transporter ,Skeletal muscle ,General Medicine ,Up-Regulation ,medicine.anatomical_structure ,Endocrinology ,nervous system ,biology.protein ,Female ,GLUT4 - Abstract
The purpose of the present study was to investigate whether peripheral brain-derived neurotrophic factor (BDNF) treatment induced metabolic adaptations in mouse skeletal muscle. BDNF (20 mg/kg/day) was injected subcutaneously for successive 14 days. BDNF treatment significantly reduced the total food intake and inhibited the weight gain in comparison to the control group. The glucose transporter 4 (GLUT4) protein expression in the gastrocnemius muscle was significantly increased by BDNF treatment in comparison to the control and pair-fed groups. Neither the oxidative nor the glycolytic enzyme activities in the gastrocnemius muscle changed after the BDNF treatment. These results suggest that the peripheral BDNF treatment promotes the skeletal muscle GLUT4 protein expression as well as hypophagia.
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- 2010
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53. High-precision sample stage for photoemission microscopy of organic films
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Takashi Yamada, Toshiaki Munakata, I. Yamamoto, N. Matsuura, and Keisuke Miyakubo
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Radiation ,Materials science ,business.industry ,Resolution (electron density) ,Condensed Matter Physics ,Translation (geometry) ,Sample (graphics) ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,Organic semiconductor ,chemistry.chemical_compound ,Optics ,chemistry ,law ,Phthalocyanine ,Stage (hydrology) ,Graphite ,Physical and Theoretical Chemistry ,Electron microscope ,business ,Spectroscopy - Abstract
A high-precision sample stage for photoemission microscopy has been constructed to translate the sample by ±3 mm with accuracy better than 100 nm. The stage is actuated by step motors settled outside the vacuum. The accuracies of the translations were measured by observing a standard patterned sample with a photoemission electron microscope (PEEM) of 50 nm resolution. The accuracy was nearly independent of the distance of each translation step and the error was not accumulated by repeated steps. After round-trip translations up to 0.2 mm, the sample came back to the original position with accuracy of ±50 nm. The performance of the stage was demonstrated by observing growth processes of lead phthalocyanine (PbPc) films formed on graphite.
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- 2009
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54. Permeability of 5-fluorouracil and its prodrugs in Caco-2 cell monolayers: evidence for shift from paracellular to transcellular transport by prodrug formation
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Hidekazu Azuma, Masaki Otagiri, I. Yamamoto, Teruko Imai, and M. Imoto
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Stereochemistry ,Chemistry ,Permeability (electromagnetism) ,Paracellular transport ,Biophysics ,Pharmaceutical Science ,Efflux ,Prodrug ,Transcellular ,Apical membrane ,Permeation ,Membrane transport - Abstract
The membrane transport properties of 5-FU and its prodrugs were investigated using Caco-2 cell monolayers. To elucidate a membrane transport of prodrug itself, 2-O-alkoxy-5-fluoropyrimidone (2-O-alkoxy-5FP) derivative, which was stable in buffer and Caco-2 cell, was selected as a test compound. The permeation of 2-O-alkoxy-5FP derivatives was markedly greater than that of 5-FU. The dose-dependency of apical to basal (AP-BL) and BL-AP transports showed that 5-FU was dominantly transported by passive diffusion and ethoxy-5FP was transported by passive diffusion and unsaturated efflux transporter in the apical membrane of Caco-2 cell monolayers. Furthermore, treatment of Cap-Na, an enhancer of paracellular transport, demonstrated that 5-FU and 2-O-alkoxy-5FP derivatives permeated through paracellular and transcellular route, respectively. The significantly increased permeability of 2-O-alkoxy-5FP derivatives was mainly related to capping of hydrophilic functional group, and the moderate increase in permeability among 2-O-alkoxy-5FP derivatives was dependent on prolongation of the alkyl chain length.
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- 2009
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55. Extent of hepatitis E virus elimination is affected by stabilizers present in plasma products and pore size of nanofilters
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Mikihiro Yunoki, H. Tanaka, S. Hattori, M. Yoshikawa, Hiromi Nishigaki, Katsuro Hagiwara, Y. Tanaka, I. Yamamoto, Kazuyoshi Ikuta, J. Adan-Kubo, Muneo Tsujikawa, Takeru Urayama, S. Yamamoto, and A. Nishida
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Hot Temperature ,Time Factors ,Genotype ,Swine ,viruses ,Serum albumin ,Sodium Chloride ,Arginine ,Virus Replication ,medicine.disease_cause ,Virus ,Excipients ,Feces ,Plasma ,Hepatitis E virus ,medicine ,Animals ,Nanotechnology ,Citrates ,Serum Albumin ,Infectivity ,Detection limit ,Chromatography ,biology ,Chemistry ,Micropore Filters ,Albumin ,Fibrinogen ,Hematology ,General Medicine ,Viral Load ,Solutions ,Biochemistry ,Viral replication ,biology.protein ,RNA, Viral ,Virus Inactivation ,Viral load ,Filtration - Abstract
Background and Objective To investigate the physico-chemical properties of hepatitis E virus (HEV) with regard to inactivation/removal, we have studied four isolates with respect to sensitivity to heat during liquid/dry-heating as well as removal by nanofiltration. Materials and Methods Hepatitis E virus in an albumin solution or phosphate-buffered saline (PBS) was liquid-heated at 60°C for a preset time. HEV in a freeze-dried fibrinogen containing stabilizers was also dry-heated at 60 or 80°C for a preset time. In addition, to clarify the removal of HEV, the purified virus in PBS was filtered using several types of virus-removal filter (nanofilters) that have different pore sizes. HEV infectivity or genome equivalents before and after the treatments were assayed by a semiquantitative cell-based infectivity assay or quantitative polymerase chain reaction assay, respectively. Results Hepatitis E virus isolates in albumin solutions were inactivated slowly at 60°C for 5 h and the resultant log reduction factor (LRF) was from 1·0 to ≥ 2·2, whereas the virus in PBS was inactivated quickly to below the detection limit and the LRF was ≥ 2·4 to ≥ 3·7. The virus in a freeze dried fibrinogen containing trisodium citrate dihydrate and l-arginine hydrochloride as stabilizers was inactivated slowly and the LRF was 2·0 and 3·0, respectively, of the 72 h at 60°C, but inactivated to below the detection limit within 24 h at 80°C with an LRF of ≥ 4·0. The virus in PBS was also confirmed as to be approximately 35 nm in diameter by nanofiltration. These results are useful for evaluating viral safety against HEV contamination in blood products. Conclusion The sensitivity of HEV to heat was shown to vary greatly depending on the heating conditions. On the other hand, the HEV particles were completely removed using 20-nm nanofilters. However, each inactivation/removal step should be carefully evaluated with respect to the HEV inactivation/removal capacity, which may be influenced by processing conditions such as the stabilizers used for blood products.
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- 2008
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56. Imaging of electronic structure of lead phthalocyanine films studied by combined use of PEEM and Micro-UPS
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I. Yamamoto, N. Matsuura, Toshiaki Munakata, Nobuo Ueno, R. Yamamoto, M. Mikamori, Keisuke Miyakubo, and Takashi Yamada
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Chemistry ,Photoemission spectroscopy ,Bilayer ,Analytical chemistry ,Surfaces and Interfaces ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Organic semiconductor ,Photoemission electron microscopy ,X-ray photoelectron spectroscopy ,Monolayer ,Materials Chemistry ,Work function ,Thin film - Abstract
The thin film growth of lead phthalocyanine (PbPc) on graphite substrate has been studied by photoemission electron microscopy (PEEM) operated with tunable UV laser radiation. Origin of the contrast of PEEM images was elucidated by comparison with microspot ultraviolet photoemission spectroscopy (Micro-UPS). The photoelectron yield curves measured with PEEM for annealed films of different coverages were in agreement with the shifts of the vacuum levels determined by Micro-UPS. Below 1 monolayer (ML) coverage, PbPc molecules did not form islands/domains but were sparsely distributed and formed uniform films. Above 1 ML, PbPc molecules formed stable islands of bilayer in a well-ordered 1 ML film. On the other hand, for as-deposited films with thickness equivalent to annealed 0.3 ML coverage, PbPc molecules formed metastable bilayer islands of a few μm-size in the sparsely packed uniform film. These results demonstrate the capability of combined use of the complementary methods PEEM and Micro-UPS to resolve inhomogeneity of electronic structure.
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- 2008
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57. Muon components detected by EAS array and Okayama muon telescope experiments
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A. Iyono, C. Noda, H. Matsumoto, M. Masuda, M. Okita, K. Okei, T. Morita, N. Takahashi, N. Ochi, T. Konishi, T. Nakatsuka, S. Ohara, S. Tsuji, T. Wada, I. Yamamoto, Y. Yamashita, T. Nakamura, and K. Saitoh
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Physics ,Nuclear and High Energy Physics ,Muon ,Physics::Instrumentation and Detectors ,Astrophysics::High Energy Astrophysical Phenomena ,Computer Science::Neural and Evolutionary Computation ,Astrophysics::Instrumentation and Methods for Astrophysics ,Electron ,Atomic and Molecular Physics, and Optics ,law.invention ,Nuclear physics ,Telescope ,Air shower ,law ,High Energy Physics::Experiment - Abstract
The Okayama muon telescope and the extensive air shower (EAS) array in Large Area Air Shower (LAAS) experiments were used to measure both muon and electron components in EAS events. The average ratio of the number of muon tracks to electron tracks 0.01 ± 0.005 was derived from this analysis, which is consistent with the typical core distance of EAS from the telescope in PeV energies derived from EAS simulation results.
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- 2008
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58. Highly Manufacturable and Reliable HfSiON N-FET With Poly-Si/a-Si Stacked Gate for LSTP Applications
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I. Yamamoto, Y. Yasuda, Y. Yamagata, and K. Imai
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Materials science ,business.industry ,Transistor ,Gate dielectric ,Electrical engineering ,Condensed Matter Physics ,Industrial and Manufacturing Engineering ,Electronic, Optical and Magnetic Materials ,law.invention ,law ,Gate oxide ,Low-power electronics ,Electrode ,Optoelectronics ,Field-effect transistor ,Electrical and Electronic Engineering ,business ,High-κ dielectric ,Leakage (electronics) - Abstract
We have proposed a novel poly-Si/a-Si/HfSiON transistor to enhance reliabilities without performance degradation for a 65-nm-node low standby power (LSTP) application. By insertion of a thin amorphous-Si layer between the Poly-Si gate electrode and HfSiON, both phosphorus penetration from gate electrode and a reaction at gate electrode/HfSiON interface are successfully suppressed, so that positive bias temperature instability, one of the biggest issues for high-k gate dielectric, is drastically improved by two orders of magnitude. By carefully optimizing the gate stack structure of HfSiON, the HfSiON device can satisfy both lower gate leakage and gate-induced drain leakage at the same time. As a result, an excellent Ion- Istandby (= Ig + loff) characteristic can be achieved, compared to the conventional SiON device. The a-Si insertion technique can realize the combination between the high-k gate dielectric and Poly-Si for future LSTP applications.
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- 2008
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59. The anisotropy of cosmic ray flux in Large Area Air Shower experiments
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C. Noda, A. Iyono, H. Matsumoto, M. Masuda, M. Okita, K. Okei, T. Morita, N. Takahashi, N. Ochi, T. Konishi, T. Nakatsuka, S. Ohara, S. Tsuji, T. Wada, I. Yamamoto, Y. Yamashita, T. Nakamura, and K. Saitoh
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Physics ,Nuclear and High Energy Physics ,Turbulence ,Astrophysics::High Energy Astrophysical Phenomena ,Isotropy ,Cosmic ray ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Atomic and Molecular Physics, and Optics ,Amplitude ,Air shower ,Sidereal time ,Anisotropy ,Right ascension - Abstract
The sidereal anisotropy of cosmic rays with energy in the range of 10 14 – 10 15 eV was obtained by using Large Area Air Show (LAAS) experiments which deployed extensive air shower (EAS) arrays in large part of Japan. The first harmonic amplitude and phase in a function of right ascension axis are ( 0.23 ± 0.04 ) × 10 −2 and 0.4 ± 0.7 hour, respectively, and those of the second harmonics are ( 0.06 ± 0.04 ) × 10 −2 and 7.5 ± 2.6 hour, respectively. The first harmonic amplitude are compared with the diffusive mode of cosmic ray propagation, which predicts the dependence of anisotropy amplitudes on primary cosmic ray rigidities. The exponent value of rigidity dependence of diffusion coefficient is estimated as 0.34 ± 0.01 , in good agreement with Kolmogorov type spectrum of turbulence of galactic magnetic filed. Although a sky map in equatorial coordinates indicates excess and deficit regions above the isotropic expectation, their deviations were consistent with statistical ones, and more statistics are required to point the region and the opening angle of them.
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- 2008
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60. A Ferromagnetic Foreign Body at the Lateral Aspect of the Mandibular Ramus in a Medically Compromised Patient
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I Yamamoto, Tadaaki Kirita, Yumiko Matsusue, H Shimotsuji, Yohei Nakayama, and K. Yamamoto
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medicine.medical_specialty ,Mandible ,Article ,030218 nuclear medicine & medical imaging ,Masseter ,03 medical and health sciences ,0302 clinical medicine ,Magnetic resonance imaging ,medicine ,General Dentistry ,medicine.diagnostic_test ,business.industry ,030206 dentistry ,Cheek ,medicine.disease ,Surgery ,Foreign body ,medicine.anatomical_structure ,Ferromagnetic ,Right cheek ,business ,Mandibular ramus - Abstract
A case of a ferromagnetic foreign body in a medically compromised patient was reported. The patient was a 45-year-old male who consulted our department complaining of a foreign body accidentally impacted in the right cheek. X-ray examination revealed a foreign body at the lateral aspect of the right mandibular ramus. The removal of the foreign body was scheduled, but the patient did not return for the procedure. After 8 years he revisited our department for the removal of the foreign body, because it had been found to be ferromagnetic and a barrier to MRI examination. X-ray examination confirmed the foreign body was located at the same site as 8 years prior. Although the patient was suffering from liver cirrhosis with thrombocytopenia and leukopenia, the foreign body was successfully removed under general anesthesia. The foreign body was 12 × 5 × 1 mm, weighed 0.48 g, and was ferromagnetic. The patient’s postoperative course was uneventful. X-ray examination confirmed the removal of the foreign body. Since the surgery, the patient has been in generally stable condition with no complications. This case was a rare example of a foreign body that needed to be removed for medical examination.
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- 2015
61. FORMATION OF DIOXINS AND FURANS DURING MUNICIPAL SOLID WASTE GASIFICATION
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E. J. Lopes, L. A. Okamura, and C. I. Yamamoto
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Pollutant ,Pollutants ,Municipal solid waste ,Municipal Solid Waste ,Waste management ,business.industry ,Chemistry ,General Chemical Engineering ,lcsh:TP155-156 ,Thermal treatment ,Dispose pattern ,Combustion ,Dioxins ,Incineration ,Volume (thermodynamics) ,Alternative energy ,lcsh:Chemical engineering ,business ,Furans ,Gasification - Abstract
Thermal treatment is an interesting strategy to dispose of municipal solid waste: it reduces the volume and weight of the material dumped in landfills and generates alternative energy. However, the process emits pollutants, such as dioxins and furans. The present study evaluated MSW gasification-combustion integrated technologies in terms of dioxin and furan emission; and compared the obtained data with literature results on incineration, to point out which operational features differentiate the release of pollutants by these two processes. The results show that the process of integrated gasification and combustion emitted 0.28 ng N-1 m-3, expressed in TEQ (Total Equivalent Toxicity), of PCDD/F, less than the maximum limits allowed by local and international laws, whereas incineration normally affords values above these limits and requires a gas treatment system. The distinct operational conditions of the two thermal processes, especially those related to temperature and the presence of oxygen and fixed carbon, led to a lower PCDD/F emission in gasification.
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- 2015
62. SIMULAÇÃO NUMÉRICA DA INJEÇÃO DE CO2 DISSOLVIDO EM ÁGUA EM AMOSTRAS DE ROCHAS CARBONÁTICAS DE RESERVATÓRIO DE PETRÓLEO
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L. F. L. Luz, E. V. Takeshita, C. I. Yamamoto, and A. V. L. Machado
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Materials science - Published
- 2015
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63. ADITIVOS PARA A MELHORIA DAS PROPRIEDADES DE ESCOAMENTO DO BIODIESEL A FRIO
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M. Balen, C. I. Yamamoto, and Valcineide Oliveira de Andrade Tanobe
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Materials science - Published
- 2015
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64. Performance improvement of CMOS device utilizing poly-Si/HfSiON gate stack and its reliability concern for 65nm technology and beyond
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Naohiko Kimizuka, K. Tsuneki, I. Yamamoto, Toshiyuki Iwamoto, Kiyotaka Imai, Y. Yasuda, T. Abe, Y. Akiyama, Shinji Fujieda, and K. Takano
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Materials science ,business.industry ,Mechanical Engineering ,Time-dependent gate oxide breakdown ,Propagation delay ,Dielectric ,Condensed Matter Physics ,Amorphous solid ,Threshold voltage ,CMOS ,Mechanics of Materials ,Optoelectronics ,General Materials Science ,business ,Standby power ,Leakage (electronics) - Abstract
We have developed low standby power (LSTP) FET utilizing HfSiON dielectric. Due to optimizations of channel and offset spacer structure, we could put threshold voltage of pFET into the place of LSTP region, working through the Fermi-level-pinning effect. This resulted in the reduction of propagation delay and in performance improvement of our test product. We could also introduce reverse body-biasing technique for standby leakage reduction even for LSTP device. In order to characterize positive bias temperature instability (PBTI) of nFET, we have evaluated the kinetics of the electron trapping in amorphous HfSiON (a-HfSiON) and partially crystallized HfSiON (c-HfSiON) dielectric. We have found that the difference in PBTI reflects the structural diversity between them, such as spatial and energy distribution of the traps. We need to take notice of such diversity and figure out the origin of PBTI. Phosphorus penetration into HfSiON should be avoided in terms of gate leakage increase and TDDB degradation. To suppress it, we proposed double-layer gate electrode structure, which consisted of as-deposited amorphous layer followed by poly-Si layer.
- Published
- 2006
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65. Prevalence of hepatitis C virus infection in cases of B-cell lymphoma in Japan
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Koichi Higaki, T Muranaka, I Yamamoto, Morishige Takeshita, S Okamura, H Sakai, Yumi Oshiro, K Shimamatsu, and Naokuni Uike
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Adult ,Male ,Epstein-Barr Virus Infections ,Lymphoma, B-Cell ,Histology ,Adolescent ,Genotype ,Hepatitis C virus ,Hepacivirus ,Comorbidity ,Viral Nonstructural Proteins ,medicine.disease_cause ,Virus ,Pathology and Forensic Medicine ,Flaviviridae ,Japan ,Viral Envelope Proteins ,hemic and lymphatic diseases ,Prevalence ,medicine ,Humans ,Child ,B-cell lymphoma ,Aged ,biology ,business.industry ,Incidence ,Incidence (epidemiology) ,General Medicine ,Middle Aged ,Hepatitis B ,medicine.disease ,biology.organism_classification ,HTLV-I Infections ,Hepatitis C ,Lymphoma ,Cryoglobulinemia ,Immunology ,RNA, Viral ,Female ,Lymphoma, Large B-Cell, Diffuse ,Viral disease ,business - Abstract
Aims : To determine the prevalence of hepatitis C virus (HCV) infection in B-cell lymphoma in Japan. HCV infection and type II (monoclonal IgM) cryoglobulinaemia (CG) may be involved in the pathogenesis of low-grade B-cell lymphoma (ML) in southern Europe. Methods and results : Forty-five (11.3%) of 400 B-cell ML cases were HCV antibody (Ab) positive, which was significantly (P
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- 2006
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66. Substrate Dependent Anisotropic Diffusion Of Indium Atoms On Ptcda Thin Films Studied by Peem
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Nobuo Ueno, Miki Onoue, I. Yamamoto, Masakazu Shionoiri, Satoshi Kera, and K.K. Okudaira
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Surface diffusion ,Materials science ,Mechanical Engineering ,Metals and Alloys ,chemistry.chemical_element ,Substrate (electronics) ,Condensed Matter Physics ,Microstructure ,Fick's laws of diffusion ,Molecular physics ,Electronic, Optical and Magnetic Materials ,Crystal ,Crystallography ,chemistry ,Mechanics of Materials ,Materials Chemistry ,Thin film ,Anisotropy ,Indium - Abstract
Anisotropic surface diffusion of In atoms was observed by photoelectron emission microscopy (PEEM) when a square-shaped microstructure of In metal was deposited onto thin films of perylene-3,4,9,10-tetracarboxyric acid-dianhydride (PTCDA) grown on cleaved MoS 2 and GeS surfaces. For In microstructure on PTCDA/MoS 2 system, the PEEM images showed a triangle pattern, although the deposited shape of the In microstructure was square, indicating that In atoms diffuse to three directions on PTCDA/MoS 2 . Such triangle pattern was not observed on PTCDA/GeS but an oval structure was observed, revealing that In atoms diffuse to two directions on PTCDA/GeS with different diffusion constant. The two directions correspond well with surface crystal axes of GeS. Since the unit cells of PTCDA adsorbed on these two crystal surfaces are nearly the same, it is suggested that different anisotropic diffusion of In in these systems is related to strong In-PTCDA interaction which may be affected by the surface structure of underlying substrate.
- Published
- 2005
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67. An 8k × 4k Ultrahigh-Definition Color Video Camera with 8M-Pixel CMOS Imager
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S. Yahagi, Masayuki Sugawara, Hiroshi Shimamoto, Takayuki Yamashita, J. Shimura, M. Matsuoka, Fumio Okano, Kohji Mitani, N. Koga, I. Yamamoto, and T. Tsukamoto
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education.field_of_study ,Zoom lens ,Pixel ,Computer science ,business.industry ,Video camera ,law.invention ,law ,Camera control unit ,Camera auto-calibration ,Chromatic aberration ,Media Technology ,Computer vision ,Artificial intelligence ,Electrical and Electronic Engineering ,Three-CCD camera ,education ,business ,Camera resectioning - Abstract
An ultrahigh-definition color video camera that uses new 1.25-in. 8M-pixel CMOS digital imagers and diagonal pixel shifting in a 4-pickup system has been developed. The camera head weighs less than 40 kg. A 5x zoom lens and a signal processing system incorporating a function for realtime lateral chromatic aberration correction was also developed. This function makes it possible to suppress optically generated color shifts across the entire zooming range. Moreover, opticalmultiplexing transmission equipment and a camera control unit were created. This camera has a limiting resolution of more than 3200 TV lines. The signal-to-noise ratio (SNR) on an HDTV video, which is extracted 1/16 from 8k x 4k pixels video for the reason of SNR measurement device, was about 45 dB. The sensitivity was 2000 lux at F2.8 with a dynamic range of 200%.
- Published
- 2005
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68. An animatronic system including lifelike robotic fish
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I. Yamamoto and Y. Terada
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Engineering ,Fin ,Event (computing) ,business.industry ,Mobile robot ,Robotics ,Propulsion ,GeneralLiterature_MISCELLANEOUS ,%22">Fish ,Robot ,Animatronics ,Artificial intelligence ,Electrical and Electronic Engineering ,business ,Simulation ,Marine engineering - Abstract
This paper provides an outline of a new animatronic system, based on the technology of the flexible oscillating fin. The oscillating fin propulsion system was designed and constructed to be combined with a ship model. The system's feasibility has been confirmed by tank tests using the ship model. As a result, several advantages of the oscillating fin system have been found. A neural network was successfully applied for an identification of the ship model dynamics with the oscillating fin and its effectiveness was confirmed. The animatronic system is a computer-controlled biomechanically engineered model, rapidly gaining popularity throughout the world. We have developed aquatic robots with oscillating fins for the animatronics system to build a virtual aquarium. We have proposed an exhibition system for enhancing event spaces that includes an animatronic system for modern-day fish, coelacanths, and Cambrian-world creatures, able to swim under their own electric power.
- Published
- 2004
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69. The effect of bisphenol A and chlorinated derivatives of bisphenol A on the level of serum vitellogenin in Japanese medaka (Oryzias latipes)
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Yasumoto Magara, Tasuku Kamei, M. Itoh, Y. Terao, Yuta Ohnishi, Akihisa Tabata, I. Yamamoto, and N. Watanabe
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endocrine system ,medicine.medical_specialty ,Bisphenol A ,Environmental Engineering ,biology ,urogenital system ,Chemistry ,Oryzias ,Environmental exposure ,Japanese Medaka ,biology.organism_classification ,chemistry.chemical_compound ,Vitellogenin ,Endocrinology ,Internal medicine ,Sodium hypochlorite ,polycyclic compounds ,Water environment ,medicine ,biology.protein ,Vitellogenesis ,hormones, hormone substitutes, and hormone antagonists ,Water Science and Technology - Abstract
2,2-bis (4-hydroxyphenyl) propane or Bisphenol A (BPA), has been reported to behave as an endocrine disrupter below acute toxic levels, and is widely present in the water environment. Although BPA is easily chlorinated, very little is reported on the effect of chlorinated BPA to the aquatic organisms. In this study, the estrogenic activities of BPA and its chlorinated derivatives were evaluated by the induction of vitellogenin (VTG) in the serum of mature male Japanese medaka. In addition, the effect of sodium hypochlorite on the decomposition of BPA was tested. The relative potencies of estrogenic activities of chlorinated BPA descended in the order 3,3′-diClBPA>BPA≥3-ClBPA>3,3′,5-triClBPA, and no estrogenic activity was observed in 3,3′,5,5′-tetraClBPA. Lowest Observed Effect Concentration (LOEC) and No Observed Effect Concentration (NOEC) for both 3-ClBPA and 3,3′-diClBPA were 500 μg/L and 200 μg/L, respectively. LOEC for 3,3′,5-triClBPA was >500 μg/L. When BPA was reacted with sodium hypochlorite (24 hours; residual chlorine at 1 ppm), however, complete decomposition of BPA and its chlorinated derivatives was observed. The decrease in BPA and its chlorinated derivatives paralleled the decrease in estrogenic potency evaluated by the induction of vitellogenin (VTG) in the serum of mature male Japanese medaka.
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- 2004
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70. Optical and time-resolved electron paramagnetic resonance studies of the excited states of para-methylcinnamic acid and para-methylcinnamate anion
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Mikio Yagi, I. Yamamoto, R. Sasase, and Kanekazu Seki
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Chemistry ,Resonance ,Photochemistry ,Fluorescence ,Atomic and Molecular Physics, and Optics ,law.invention ,Crystallography ,Deprotonation ,Intersystem crossing ,law ,Excited state ,Molecular orbital ,Phosphorescence ,Electron paramagnetic resonance - Abstract
Time-resolved electron paramagnetic resonance (EPR), fluorescence, and phosphorescence spectra have been observed for the excited states oftrans-p-methylcinnamic acid (p-MeCA) andtrans-p-methylcinnamate anion (p-MeCA−) in rigid organic glasses at 77 K. With a stretched-polymer-film technique, we assigned the resonance fields in the time-resolved EPR spectra of the lowest excited triplet (T1) states ofp-MeCA andp-MeCA−. From the analysis of these spectra we concluded that the deviation from planar structure in the T1 state is small inp-MeCA andp-MeCA− and the direction of C=O iss-cis to the ethylenic C=C bond inp-MeCA. The deprotonation appears to have little effect on the zero-field splitting (ZFS) parameters. The ZFS parameters were calculated theoretically using semiempirical molecular orbitals. The sublevel preferentially populated by intersystem crossing (ISC) is T y in bothp-MeCA andp-MeCA−. However, following the deprotonation ofp-MeCA, (P y−P z)/(P x−P z) changes from 5.7 inp-MeCA to 2.1 inp-MeCA− (P i are relative populating rates; thex andy axes are close to the long and short in-plane molecular axes, respectively, andz-axis is perpendicular to the molecular plane). The fluorescence lifetimes indicate that the deprotonation has little effect on the sum of the three ISC rate constants for the three T1 sublevels. A decrease in acidity ofp-MeCA upon excitation has been observed.
- Published
- 2003
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71. Chaos in different far-off cosmic rays: a fractal wave model
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S Ohara, T Konishi, K Tsuji, M Chikawa, Y Kato, T Wada, N Ochi, I Yamamoto, N Takahashi, W Unno, T Kitamura, and Large Area Air Shower (LAAS) Group
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Nonlinear Sciences::Chaotic Dynamics ,Physics ,Nuclear and High Energy Physics ,Air shower ,Fractal ,Astrophysics::High Energy Astrophysical Phenomena ,Chaotic ,Cosmic ray ,Astrophysics ,Galactic plane ,Right ascension ,Fractal dimension ,Earth's rotation - Abstract
The air shower arrival time intervals (ASATIs) were observed for several years at five different far-off stations to study the chaotic feature of the cosmic rays. The total number of chaotic time series of ASATIs is 99 from February 1994 to November 2000. The chaotic ASATIs appear six times simultaneously between two different stations, showing a higher probability of simultaneous chaos detection than the random occurrence as implied by the fractal wave pattern of cosmic ray clouds. The average fractal dimension of the fractional chaotic ASATIs for each station is 3.7 ± 0.1 pm with average duration of 23 h. The distribution of the representative (central) right ascension of air showers among 99 chaotic ASATIs has two peaks around 4 h and 20 h. The time variation of the chaotic feature of the ASATIs for several days shows a quasi-periodic behaviour with the rotation of the earth. These results seem to indicate that the chaotic cosmic rays arrive at the earth, forming wave trains like a fractal pattern which covers an area of the galactic plane surrounding the earth.
- Published
- 2003
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72. Search for large-scale coincidences in network observation of cosmic ray air showers
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N Ochi, A Iyono, H Kimura, T Konishi, T Nakamura, T Nakatsuka, S Ohara, N Ohmori, K Okei, K Saitoh, N Takahashi, S Tsuji, T Wada, I Yamamoto, Y Yamashita, Y Yanagimoto, and the Large Area Air Shower (LASS) group
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Physics ,Nuclear and High Energy Physics ,Air shower ,Crab Nebula ,Coincident ,Scintillation counter ,Detector ,Astronomy ,Cosmic ray ,Scale (descriptive set theory) ,Astrophysics ,Time correlation - Abstract
The Large Area Air Shower (LAAS) group has been performing a network observation of extensive air showers (EAS) since 1996 in Japan. Eight compact EAS arrays (ten in the near future) are operating simultaneously and independently at distant stations (up to ≈ 1000 km), constituting a gigantic detector system as a whole. Using five stations' datasets, large-scale coincidences of EAS have been searched for with the aim of detecting signals from extremely short bursts in the universe. By comparing arrival times and arrival directions of all registered EAS, three coincident and parallel EAS pairs were extracted out of a sea of background cosmic rays. One of them was observed almost from the direction of the Crab Nebula, a previously reported ultra-high-energy γ-ray source. The first application reported here allows the analysis techniques to be tested and demonstrates the potential of observations with the full operation of the network detector system.
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- 2003
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73. Clinical pilot studies on pre-operative hyperthermic tumour ablation for advanced breast carcinoma using an 8 MHz radiofrequency heating device
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S Hayashi, K Nemoto, N Igarashi, H Ohkubo, Makoto Takahashi, T Ashida, T Mutou, Shigeru Fujimoto, Kokuriki Kobayashi, T Toyasawa, and I Yamamoto
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Adult ,Hyperthermia ,Cancer Research ,medicine.medical_specialty ,Physiology ,medicine.medical_treatment ,Mammary gland ,Breast Neoplasms ,Pilot Projects ,Mastectomy, Modified Radical ,Breast cancer ,Physiology (medical) ,medicine ,Carcinoma ,Humans ,Electrodes ,Survival rate ,Aged ,Intraoperative Care ,business.industry ,Cancer ,Hyperthermia, Induced ,Middle Aged ,Prognosis ,medicine.disease ,Surgery ,Survival Rate ,Treatment Outcome ,Coagulative necrosis ,medicine.anatomical_structure ,Female ,Radiology ,business ,Mastectomy ,Follow-Up Studies - Abstract
The multimodality treatment approach for advanced breast cancer provides survival advantages with decreased locoregional and distant recurrences, but these intensive anti-tumour treatments cause severe myelosuppression. Thus, in this study, the usefulness of pre-operative anti-tumour treatment without myelosuppression was investigated. Nine patients with advanced breast carcinoma underwent pre-operative hyperthermic tumour ablation (HTA) using an 8 MHz radiofrequency (RF) heating device (Thermotron RF-8) combined with a grounded needle electrode. The patients had a mean age of 58.3+/-13.9 years and included four patients with stage IIIA, two with stage IIIB and three with stage IV cancer. The target temperature was over 50 degrees C. They tolerated pre-operative HTA therapy well with no early or late complications. The initial mean tumour size was 122.1+/-71.5 cm3 and the post-HTA tumour size was 82.2+/-63.4 cm3; the reduction rate was significant (p = 0.000 293). After the pre-operative HTA, all patients underwent surgery with Level III nodal extirpation. Post-operatively, no locoregional recurrence was observed. Microscopic examination of the primary focus showed complete coagulation necrosis expanding for a diameter of 3.5-5.0 cm. Taken together, the pre-operative HTA was a safe, well-tolerated and effective treatment, achieving tumour reduction as well as complete coagulation necrosis that resulted in a large volume of destruction in breast cancer tissue.
- Published
- 2003
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74. Parallel-connected five-level PWM inverters
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Masaru Hasegawa, I. Yamamoto, K. Kondo, Keiju Matsui, and H. Mori
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Total harmonic distortion ,Engineering ,Power rating ,Control theory ,business.industry ,Harmonics ,Harmonic ,Inverter ,Static VAR compensator ,Power factor ,Electrical and Electronic Engineering ,business ,Pulse-width modulation - Abstract
Multilevel PWM inverters have significant advantages over the conventional one because of the capability of operating the motor with nearly sinusoidal current waveforms and higher output voltages. In order to increase the power rating of the inverter, connection in parallel would be effective in the present case. In high-power applications, for instance, the carriers should be synchronized to the modulating sinusoidal waves. Moreover, for the interphase reactor, lower order harmonic application is prohibited. In practice, to improve the harmonic characteristics of the parallel-connected five-level inverter, two modulation strategies have been devised and designed in this paper. It is found that the DC current flow through the DC power supplies can be controlled by means of phase shifting of the injected third order harmonics. In the case of a static VAr compensator (SVC), the output capacitor voltages can be controlled by means of this technique.
- Published
- 2003
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75. Loss of function mutant of ter94, Drosophila VCP, partially enhanced motor neuron degeneration induced by knockdown of TBPH, Drosophila TDP-43
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I. Yamamoto, Masanori Nakagawa, Ikuko Mizuta, Yukie Kushimura, Yoshitaka Nagai, M. Yamaguchi, Morio Ueyama, Toshiki Mizuno, H. Yoshida, Takahiko Tokuda, and Yumiko Azuma
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Gene knockdown ,Neurology ,biology ,Mutant ,Motor neuron degeneration ,Neurology (clinical) ,Drosophila (subgenus) ,biology.organism_classification ,Loss function ,Cell biology - Published
- 2017
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76. The search for genes that modulate FUS-mediated phenotypes by Drosophila amyotrophic lateral sclerosis model
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M. Yamaguchi, Toshiki Mizuno, Ikuko Mizuta, Takahiko Tokuda, Yukie Kushimura, Masanori Nakagawa, Yoshitaka Nagai, Morio Ueyama, I. Yamamoto, Yumiko Azuma, and H. Yoshida
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Neurology ,medicine ,Neurology (clinical) ,Amyotrophic lateral sclerosis ,Biology ,Drosophila (subgenus) ,medicine.disease ,biology.organism_classification ,Phenotype ,Gene ,Cell biology - Published
- 2017
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77. Enhanced Hemodynamics of Anisometric TPMS Topology Reduce Blood Clotting in 3D Printed Blood Contactors.
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Hirschwald LT, Hagemann F, Biermann M, Hanßen P, Hoffmann P, Höhs T, Neuhaus F, Tillmann MT, Peric P, Wattenberg M, Stille M, Fechter T, Theißen A, Winnersbach P, Barbian KP, Jansen SV, Steinseifer U, Wiegmann B, Rossaint R, Wessling M, Bleilevens C, and Linkhorst J
- Abstract
Artificial organs, such as extracorporeal membrane oxygenators, dialyzers, and hemoadsorber cartridges, face persistent challenges related to the flow distribution within the cartridge. This uneven flow distribution leads to clot formation and inefficient mass transfer over the device's functional surface. In this work, a comprehensive methodology is presented for precisely integrating triply periodic minimal surfaces (TPMS) into module housings and question whether the internal surface topology determining the flow distribution affects blood coagulation. Three module types are compared with different internal topologies: tubular, isometric, and anisometric TPMS. First, this study includes a computational fluid dynamics (CFD) simulation of the internal hemodynamics, validated through experimental residence time distributions (RTD). Blood tests using human whole blood and subsequent visualization of blood clots by computed tomography, allow the quantification of structure-induced blood clotting. The results indicate that TPMS topologies, particularly anisometric ones, serve as effective flow distributors and significantly reduce and delay blood clotting compared to conventional tubular geometries. For these novel TPMS modules, the inner surfaces can be activated chemically or functionalized to function as a selective adsorption site or biocatalytic surface or made of a permeable material to facilitate mass transfer., (© 2024 The Author(s). Advanced Healthcare Materials published by Wiley‐VCH GmbH.)
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- 2024
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78. A hydrophobic area of the GABA ρ₁ receptor containing phenylalanine 124 influences both receptor activation and deactivation
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J E, Carland, I, Yamamoto, J R, Hanrahan, H, Abdel-Halim, T M, Lewis, N, Absalom, and M, Chebib
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Binding Sites ,Phenylalanine ,Xenopus ,Molecular Sequence Data ,Mutation, Missense ,Molecular Dynamics Simulation ,HEK293 Cells ,Receptors, GABA ,Animals ,Humans ,Amino Acid Sequence ,Hydrophobic and Hydrophilic Interactions ,gamma-Aminobutyric Acid ,Protein Binding - Abstract
Experimental evidence suggests that GABA ρ1 receptors are potential therapeutic targets for the treatment of a range of neurological conditions, including anxiety and sleep disorders. Homology modelling of the GABA ρ1 extracellular N-terminal domain has revealed a novel hydrophobic area that extends beyond, but not including the GABA-binding site. Phenylalanine 124 (F124) is predicted to be involved in maintaining the structural integrity of the orthosteric-binding site. We have assessed the activity of a series of GABA ρ1 receptors that incorporate a mutation at F124. Wild-type and mutant human GABA ρ1 subunits were expressed in Xenopus laevis oocytes and AD293 cells, and the pharmacology and kinetic properties of the receptors were measured using electrophysiological analysis. Mutation of F124 had minimal effect on receptor pharmacology. However, the rate of deactivation was significantly increased compared to wild type. This study provides further information about the role of residues within a novel hydrophobic area of the GABA ρ1 receptor. This knowledge can help future studies into the design of potent and subtype-selective ligands with therapeutic value.
- Published
- 2014
79. Study of the c.r. composition and interaction at E0 = 10 – 100 TeV from the observation of H.E. muons and atmospheric Cherenkov light in EAS
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F. Gomez Serito, L. Pinsky, G.T. Zatsepin, A. Turtelli, A. De Silva, P. V. Korchaguin, B. Alessandro, R. Nania, A. Contin, A. Megna, L. G. Dos Santos, G. Badino, F. Cindolo, J.A. Chinellato, C. Morello, N. Inoue, M. Selvi, G.C. Trinchero, K. Lau, F. Arneodo, E.D. Alyea, V.S. Berezinsky, A. Chiavassa, A. Bosco, V.P. Talochkin, V. G. Ryasny, P. Dominici, R. Granella, F. F. Khalchukov, M. Basile, Antonella Castellina, E. S. Hafen, V. A. Kudryavtsev, R. Bertoni, G. Sartorelli, R. I. Enikeev, I. Yamamoto, P. Vallania, J. Moromisato, G. Cara Romeo, B. D'Ettorre Piazzoli, R. Weinstein, P. Picchi, G. Cini Castagnoli, G. Bari, G. Vigorito, F. Grianti, E. von Goeler, A. Zichichi, L. Emaldi, A. Pesci, I.A. Pless, O. Saavedra, G. Navarra, N. Mengotti Silva, S. Vernetto, P. Giusti, G. Mannocchi, J. Pyrlik, L. Periale, V. L. Dadykin, V. B. Korchaguin, T. Wada, O.G. Ryazhskaya, N. Taborgna, G. Bonoli, G. Conforto, M. E. Bertaina, J. Tang, L. Panaro, M. Luvisetto, Marco Aglietta, F. Bersani, M. Widgoff, R. Mantovani, S. Santini, B. Alpat, G. Guidi, P. b. Ghia, V.F. Yakushev, E. Kemp, Giuseppe Iacobucci, I. Uman, F. Vetrano, M. Deutsch, G. Maccarone, W. Fulgione, C. Castagnoli, F. L. Fabbri, K. Saitoh, A. S. Malguin, C. Ghetti, S. Tsuji, L. Votano, G. Van Buren, E. V. Korolkova, P. Haridas, Pietro Antonioli, Luisa Cifarelli, M. Iacovacci, G. Di Sciascio, T. Massam, G. Bruni, L. Bergamasco, P. Galeotti, B. Mayes, M., Aglietta, B., Alessandro, B., Alpat, E. D., Alyea, P., Antonioli, F., Arneodo, G., Badino, G., Bari, M., Basile, V. S., Berezinsky, L., Bergamasco, F., Bersani, M., Bertaina, R., Bertoni, G., Bonoli, A., Bosco, G., Bruni, G. C., Romeo, C., Castagnoli, A., Castellina, A., Chiavassa, G. C., Castagnoli, J. A., Chinellato, L., Cifarelli, F., Cindolo, G., Conforto, A., Contin, V. L., Dadykin, D'ETTORRE PIAZZOLI, Benedetto, A. D., Silva, M., Deutsch, G. D., Sciascio, P., Dominici, L. G., Do, L., Emaldi, R. I., Enikeev, F. L., Fabbri, W., Fulgione, P., Galeotti, C., Ghetti, P., Ghia, P., Giusti, F. G., Serito, R., Granella, F., Grianti, G., Guidi, E. S., Hafen, P., Harida, G., Iacobucci, Iacovacci, Michele, N., Inoue, E., Kemp, F. F., Khalchukov, E. V., Korolkova, P. V., Korchaguin, V. B., Korchaguin, V. A., Kudryavtsev, K., Lau, M., Luvisetto, G., Maccarone, A. S., Malguin, G., Mannocchi, R., Mantovani, T., Massam, B., Maye, A., Megna, N. M., Silva, C., Morello, J., Moromisato, R., Nania, G., Navarra, L., Panaro, L., Periale, A., Pesci, P., Picchi, L., Pinsky, I. A., Ple, J., Pyrlik, V. G., Ryasny, O. G., Ryazhskaya, O., Saavedra, K., Saitoh, S., Santini, G., Sartorelli, M., Selvi, N., Taborgna, V. P., Talochkin, J., Tang, G. C., Trinchero, S., Tsuji, A., Turtelli, I., Uman, P., Vallania, G. V., Buren, S., Vernetto, F., Vetrano, C., Vigorito, E. v., Goeler, L., Votano, T., Wada, R., Weinstein, M., Widgoff, V. F., Yakushev, I., Yamamoto, G. T., Zatsepin, and A., Zichichi
- Subjects
Nuclear reaction ,Physics ,GRAN SASSO ,Nuclear and High Energy Physics ,Range (particle radiation) ,Particle physics ,Muon ,Astrophysics::High Energy Astrophysical Phenomena ,Cosmic ray ,Threshold energy ,Atomic and Molecular Physics, and Optics ,Nuclear physics ,High Energy Physics::Experiment ,Nucleon ,DETECTOR ,Cherenkov radiation ,Lepton - Abstract
In the energy region 10 - 100 TeV both the c.r. composition from direct measurements and the cross section for high energy secondary production in the very forward region for p-air interactions are rather uncertain. Contemporaneous measurements of the total energy and of the threshold energy/nucleon of the primary particle can be provided by the atmospheric Cherenkov light and high energy muons. These measurements are performed by the combined operation of the Cherenkov array of the EAS-TOP experiment on the surface (810 gcm(2) atmospheric depth) and of the LVD experiment in the underground Gran Sasso Laboratories (3300 m w.e.; E-mu(th) = 1.3 TeV) leading to the measurement of < N-mu > (E-mu > 1.3 TeV, E-o) in the given energy range. The combined operation of the experiments and preliminary results are reported.
- Published
- 1999
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80. Dehydration improves cryopreservation of mat rush (Juncus decipiens Nakai) basal stem buds on cryo-plates
- Author
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T, Niino, S I, Yamamoto, K, Fukui, C R, Castillo Martinez, M V, Arizaga, T, Matsumoto, and F, Engelmann
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Cryopreservation ,Glycerol ,Magnoliopsida ,Sucrose ,Cryoprotective Agents ,Plant Stems ,Equipment Design ,Desiccation ,Vitrification ,Plant Shoots ,Aluminum - Abstract
Two cryopreservation procedures using aluminium cryo-plates, termed V-Cryo-plate and D-Cryo-plate, were successfully developed for in vitro mat rush (Juncus decipiens Nakai) basal stem buds. Multiple stems induced in liquid MS medium containing 8.9 μM BA by roller culture were cut into small clumps, plated on solid MS medium and cultured for 1 week at 25 degree C. Clumps that had produced many buds were cold-hardened at 5 degree C for 1-2 months. The buds with basal stems were dissected from small clumps and precultured overnight at 25 degree C on solid MS medium containing 0.3 M sucrose. Precultured buds were placed on aluminium cryo-plates and embedded in calcium alginate gel. Osmoprotection was performed by immersing the cryo-plates for 30 min at 25 degree C in loading solution (2 M glycerol + 1.0 M sucrose). In the D-Cryo-plate procedure, the buds were dehydrated to 27-25% moisture content (fresh weight) by placing the cryo-plates in the air current of a laminar flow cabinet for 2 to 3 h. In the V-Cryo-plate procedure, buds were dehydrated by immersing the cryo-plates in PVS2 vitrification solution for 40 min at 25 degree C. In both procedures, cooling was performed by placing the cryo-plates in uncapped cryotubes, which were immersed in liquid nitrogen. For rewarming, cryo-plates were immersed in medium with 1.0 M sucrose for 20 min at room temperature. Regrowth of cryopreserved buds of line 'Kitakei 2' using D-Cryo-plate and V-Cryo-plate procedures, was 90% and 80%, respectively. The two procedures were applied to 20 additional mat rush lines. Using the V-Cryo-plate procedure resulted in regrowth ranging between 13.3 and 86.7%, with an average of 52.5%. The D-Cryo-plate led to regrowth ranging between 73.3 and 96.7%, with an average of 86.3%. The D-Cryo-plate procedure will facilitate cryostorage of mat rush germplasm.
- Published
- 2014
81. Cerebrovascular reactivity to acetazolamide in alert patients with cerebral infarction: usefulness of first-pass radionuclide angiography using 99mTc-HMPAO in monitoring cerebral haemodynamics
- Author
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C C Chang, N Kuwana, H Kanno, and I Yamamoto
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Adult ,Male ,medicine.medical_specialty ,Hemodynamics ,Technetium Tc 99m Exametazime ,Radionuclide angiography ,Ventriculography, First-Pass ,Internal medicine ,medicine.artery ,Occlusion ,Humans ,Medicine ,Carotid Stenosis ,Radiology, Nuclear Medicine and imaging ,Carbonic Anhydrase Inhibitors ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Cerebral infarction ,Cerebral Infarction ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Acetazolamide ,Stroke ,Anterior communicating artery ,Cerebral blood flow ,Cerebrovascular Circulation ,Chronic Disease ,Middle cerebral artery ,Cardiology ,Female ,Radiopharmaceuticals ,Internal carotid artery ,business - Abstract
Cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) were studied in 75 patients with cerebral infarction. All patients were alert with the symptoms of hemiparesis and/or aphasia, and were divided into two groups: 42 patients had occlusion or stenosis of >75% at the internal carotid artery or main trunk of middle cerebral artery; and 33 patients did not. Hemispheric mean CBF was measured by performing first-pass radionuclide angiography using 99mTc-hexamethylpropylene amine oxime. CVR was measured as the percentage change from the baseline mean CBF value after the administration of 500 mg acetazolamide. The CVR in both groups was significantly impaired (5.2+/-6.3%, P
- Published
- 2001
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82. AN EVALUATION OF THE EFFECTS OF SCATTERED REFLECTIONS IN A SOUND FIELD
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T. Iizuka, I. Yamamoto, Y. Suzumura, M. Sakurai, Yoichi Ando, and M. Oowaki
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Physics ,geography ,Reverberation ,geography.geographical_feature_category ,Acoustics and Ultrasonics ,Scattering ,Mechanical Engineering ,Acoustics ,Magnitude (mathematics) ,Condensed Matter Physics ,Quality (physics) ,Mechanics of Materials ,Reflection (physics) ,Sound pressure ,Scale model ,Sound (geography) - Abstract
In this paper we outline and apply a procedure to evaluate sound fields in a concert hall which involve scattered reflections. We adopted an experimental method and used a 1/10 scale model of the concert hall. Arrays of circular columns were placed in front of its walls to act as the scattering obstacles. The acoustic properties of the hall were measured both with and without the arrays of circular columns. Here, the quality of the scattered sound field was evaluated in terms of four orthogonal physical factors: sound pressure level (SPL), initial time-delay gap between the direct sound and the first reflection (Δt1), subsequent reverberation time (Tsub), and magnitude of the interaural cross-correlation function (IACC). The IACC at central seats near the stage and seating area near the columns were improved by the arrays of circular columns.
- Published
- 2000
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83. [Untitled]
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I. Yamamoto
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General Materials Science - Published
- 2009
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84. Nanoscopic imaging of mechanical properties of metal films with magnetic-force-controlled AFM
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Hirofumi Yamada, Kazumi Matsushige, Hiroshi Tokumoto, S.-I. Yamamoto, W. Mizutani, and Takao Ishida
- Subjects
Materials science ,Nickel oxide ,Analytical chemistry ,Modulus ,chemistry.chemical_element ,Young's modulus ,Surfaces and Interfaces ,Condensed Matter Physics ,Surfaces, Coatings and Films ,symbols.namesake ,Nickel ,chemistry ,Materials Chemistry ,symbols ,Thin film ,Elasticity (economics) ,Composite material ,Magnetic force microscope ,Nanoscopic scale - Abstract
We have succeeded in measuring the Young's moduli of inorganic films with a diamond tip of 160–200 nm in diameter using magnetic-force-controlled atomic force microscopy (MFC-AFM). The measurement of Young's moduli was carried out by detecting the tip amplitude on the sample with an applied force of 20 nN. This technique was applied successfully to obtain Young's moduli mapping of gold islands with 1 nm thickness and nickel films with 10 nm thickness. We obtained an effective spring constant of 3000 N m−1 on gold and 21 000 N m−1 on nickel using MFC-AFM. We could normalize the effective area of the contact radius between the tip and the sample. A value of 350 GPa was derived for the Young's modulus of the nickel film, indicative of the elasticity of native nickel oxide (NiO2). This shows that the MFC-AFM technique measures the mechanical properties of a thin layer on top of the sample.
- Published
- 1999
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85. Evaluation of the mouse lymphoma tk assay (microwell method) as an alternative to the in vitro chromosomal aberration test
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Masahiro Nakadate, Takumi Awogi, Noriko Ushio Kodani, Hiroyasu Shimada, Koichi I. Yamamoto, Toshio Sofuni, Makoto Hayashi, Yoshisuke Nishi, Noriho Tanaka, Masamitsu Honma, and Shinobu Wakuri
- Subjects
DNA damage ,Health, Toxicology and Mutagenesis ,Pharmacology ,Biology ,Gene mutation ,Toxicology ,medicine.disease_cause ,Thymidine Kinase ,Chromosome aberration ,Mice ,In vivo ,Tumor Cells, Cultured ,Genetics ,medicine ,Animals ,Leukemia L5178 ,Genetics (clinical) ,Chromosome Aberrations ,Mutation ,Mutagenicity Tests ,DNA, Neoplasm ,Molecular biology ,In vitro ,Evaluation Studies as Topic ,Toxicity ,Micronucleus test ,Mutagens - Abstract
In order to evaluate the utility of the mouse lymphoma assay (MLA) for detecting in vitro clastogens and spindle poisons and to compare it with the in vitro chromosomal aberration test (CA), we conducted an international collaborative study of the MLA that included 45 Japanese laboratories and seven overseas laboratories under the cooperation of the Ministry of Health and Welfare of Japan and the Japanese Pharmaceutical Manufacturer's Association. We examined 40 chemicals; 33 were reportedly positive in the CA but negative in the bacterial reverse mutation assay, six were negative in both assays and one was positive in both. We assayed mutations of the thymidine kinase (TK) locus (tk) of L5178Y tk +/- mouse lymphoma cells using the microwell method. According to our standard protocol, cells were exposed to the chemical for 3 h, cultured for 2 days and TK-deficient mutants were expressed in 96-well plates under trifluorothymidine. Each chemical was coded and tested by two or three laboratories. Among the 34 CA-positive chemicals, positive MLA results were obtained for 20 and negative results were obtained for nine. The remaining five chemicals were inconclusive or equivocal because of discrepant inter-laboratory results or reproduced discrepant results, respectively. Among the six CA-negative chemicals, one was negative in the MLA, two were positive and three were inconclusive. Thus, the MLA could detect only 59% (20/34) of CA-positive chemicals. We concluded that the MLA was not as sensitive as the CA. Some MLA-negative chemicals evoked positive responses in the CA only after long continuous treatment. These might also be genotoxic in the MLA with long continuous treatment. Improvement of the MLA protocol, including alteration of the duration of the treatment, might render the MLA as sensitive as the CA.
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- 1999
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86. Fatty acid metabolism and lipid secretion by perfused livers from rats fed laboratory stock and sucrose-rich diets
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M Yamamoto, I Yamamoto, Y Tanaka, and J A Ontko
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Biochemistry ,QD415-436 - Abstract
To assess the possible role of altered hepatic processing of free fatty acids in dietary sucrose-induced accumulation of triglyceride in the liver and blood plasma, livers from rats fed commercial laboratory stock and high sucrose diets were perfused both with and without oleic acid substrate. Consumption of the sucrose diet exerted a multiplicity of effects on oleic acid metabolism, characterized by decreased conversion to both ketone bodies and carbon dioxide, increased esterification into liver triglyceride, and increased secretion in triglyceride-rich lipoproteins. During the infusion of oleic acid, livers from sucrose-fed rats also exhibited decreased ketogenesis, and increased secretion of triglyceride from endogenous sources. Since oleic acid uptake from the perfusion medium was identical in both groups, the observed effects of sucrose feeding are ascribed to altered rates of intracellular metabolic processes. Mass and radiochemical analyses of perfusate ketone bodies and triglycerides were indicative of greater mobilization of triglycerides from hepatocellular lipid droplets in the livers from sucrose-fed rats. These livers contained more triglyceride and secreted more triglyceride even in the absence of infused oleic acid. In summary, the sucrose-rich diet increased the esterification:oxidation ratio of intracellular free fatty acids derived from both the circulation and endogenous sources within the hepatocyte. In response, secretion of triglyceride-rich lipoproteins by the liver and deposition of triglyceride within the liver were promoted. It is concluded that alterations in the processing of free fatty acids by the liver contribute significantly to the liver and plasma triglyceride accumulation following sucrose consumption.
- Published
- 1987
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87. Nicotinoid Insecticides and the Nicotinic Acetylcholine Receptor
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I. Yamamoto, J.E. Casida, I. Yamamoto, and J.E. Casida
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- Agriculture, Forestry
- Published
- 2012
88. Phase separation of a self-assembled monolayer made from hydrocarbon–fluorocarbon disulfide
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Hiroaki Azehara, W. Mizutani, S.-I. Yamamoto, Hirofumi Hokari, Hiroshi Tokumoto, Takao Ishida, and Masamichi Fujihira
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chemistry.chemical_classification ,Hydrocarbon ,chemistry ,Chemical engineering ,Computational chemistry ,Disulfide bond ,General Materials Science ,Self-assembled monolayer ,General Chemistry ,Fluorocarbon - Published
- 1998
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89. Phase separation of a self-assembled monolayer made from hydrocarbon-fluorocarbon disulfide
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W. Mizutani, T. Ishida, S.-I. Yamamoto, H. Tokumoto, H. Hokari, H. Azehara, and M. Fujihira
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General Materials Science ,General Chemistry - Published
- 1998
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90. Detection in human sera to excreted secreted antigens Toxoplasma gondii by use immunoblot assay of IgG, IgM and IgA from of dot ELISA and
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Y. I. Yamamoto J. R. Mineo C. S. Meneg
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Infectious Diseases ,Excreted secreted antigens ,Immunoblot Assay ,Toxoplasma gondii ,Dot elisa ,Parasitology ,Biology ,biology.organism_classification ,Microbiology - Published
- 1998
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91. Tensile properties and fracture toughness of a Ti-45Al-1.6Mn alloy at loading velocities of up to 12 m/s
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I. Yamamoto, ZhengMing Sun, Toshiro Kobayashi, H. Fukumasu, and K. Shibue
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Materials science ,Fracture toughness ,Deformation mechanism ,Mechanics of Materials ,Ultimate tensile strength ,Metallurgy ,Metals and Alloys ,Fractography ,Strain rate ,Deformation (engineering) ,Condensed Matter Physics ,Crystal twinning ,Intergranular fracture - Abstract
A γ-base TiAl alloy with duplex microstructure of lamellar colonies and equiaxed γ grains was prepared with a reactive sintering method. Tensile tests and fracture toughness tests at loading velocities up to 12 m/s (strain rate for tensile tests up to 3.2×102/s) were carried out. The micro-structure of the alloy before and after tensile deformation was carefully examined with a scanning electron microscope (SEM) and a transmission electron microscope (TEM). The fractography of the tensile specimens and fracture toughness specimens was studied. The experimental results demonstrated that the ultimate tensile strength (UTS) and yield strength (YS) increase with increasing strain rate up to 10/s and subsequently level off. The UTS and YS exhibited similar strain rate sensitivity. The strain rate sensitivity exponent at strain rates lower than 10/s is about 1.5×10−2 and at higher strain rates is almost zero. In this study, fracture toughness was found to be less sensitive to the loading velocity, having values of around 25 MPa √m, which is believed to be attributed to the high strain rate experienced at the crack tip. The predominant deformation mechanism for the strain rates used in this study was found to be twinning. However, in the low strain rate range, the dislocation motion mechanism was operative at the initial deformation stage and twinning dominated the later stage of the deformation process. In the high strain rate range, the entire deformation process was dominated by twinning. The interaction between deformation twinning and grain boundaries resulted in intergranular fracture in the γ grains and delamination of α 2/γ interfaces in the lamellar colonies.
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- 1998
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92. Detection in human sera of IgG, IgM and IgA to excreted/secreted antigens fromToxoplasma gondiiby use of dot-ELISA and immunoblot assay
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José Roberto Mineo, M. Kawarabayashi, Y. I. Yamamoto, C. S. Meneghisse, and A. C. S. Guimarães
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biology ,030231 tropical medicine ,Toxoplasma gondii ,biology.organism_classification ,medicine.disease ,Virology ,Toxoplasmosis ,Microbiology ,Pathogenesis ,Apicomplexa ,03 medical and health sciences ,0302 clinical medicine ,Infectious Diseases ,Immune system ,Antigen ,Immunity ,030225 pediatrics ,biology.protein ,medicine ,Parasitology ,Antibody - Abstract
The excreted/secreted antigens (ESA) of Toxoplasma gondii are thought to play an important role in the pathogenesis and immune escape of the parasite and the host's immunity to infection with it. In the present study, ESA from peritoneal exudates of infected mice were precipitated with ammonium sulphate (a 40% saturated solution giving the best yield of antigenic components). They were then analysed by immunoblot assay and dot-ELISA using serum samples from 25 patients with toxoplasmosis (19 in the acute phase and six chronic). Three groups of antigens, with molecular masses of 35, 30-32 and 26 kDa, reacted strongly with IgG antibodies, and antigens from two of these groups (30-32 and 26 kDa) also reacted with IgM and IgA.
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- 1998
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93. Bone fragility induced by x-ray irradiation in relation to cortical bone-mineral content
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I. Yamamoto, Hiroshi Kimura, R. Morita, and Mwijarubi M. Nyaruba
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Bone fragility ,Bone tissue ,Absorptiometry, Photon ,Bone Density ,Tensile Strength ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Tibia ,Irradiation ,Rats, Wistar ,Radiological and Ultrasound Technology ,business.industry ,Dose-Response Relationship, Radiation ,General Medicine ,Rats ,Tibial Fractures ,Disease Models, Animal ,Radiation Injuries, Experimental ,Dose–response relationship ,Fractures, Spontaneous ,medicine.anatomical_structure ,Toxicity ,Female ,Cortical bone ,Diaphyses ,X ray irradiation ,business ,Nuclear medicine ,Follow-Up Studies - Abstract
Purpose: A large single dose of irradiation to bone tissue causes bone fragility, and such bone will be susceptible to fracture even without trauma. the purpose of this study was to investigate the effects of fractional irradiation on the biomechanical properties of bone in the rat in relation to the cortical bone-mineral content (BMC), and to compare these effects with those brought about by single-dose irradiation Material and Methods: Seventy-five veteran female Wistar rats were divided into 4 groups. Group 1 was the control group. the left tibiae of the remaining rats were exposed to irradiation. Group 2 received one single dose of X-rays at 10–60 Gy. Groups 3 and 4 received fractional irradiation up to different cumulative doses (10–60 Gy): group 3 received 2.5 Gy once a day; group 4 received 1.25 Gy twice a day. Twenty-four weeks after irradiation, the rats were killed and the BMC in each tibial diaphysis was determined by dual-energy X-ray absorptiometry (DXA). the bones were then loaded to failure in a three-point bending test Results: the control group showed no difference (p Conclusion: the study suggested that bone fragility induced by single fractional irradiation doses (given once daily up to high cumulative doses) was not associated with change in the cortical BMC. It also confirmed the preference for twice-daily fractional irradiation as compared to once-daily fractional irradiation and the total single dose
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- 1998
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94. Abstracts of Papers Presented at the Japan-Israel Workshop on Novel Approaches for Controlling Insect Pests and Plant Diseases Binational Plant Protection Cooperation
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Shlomit Klopman, Szuszanna Koncz-Kaiman, A. Baider, Aviah Zilberstein, Yeheskel Antignus, Avital Regev, B. Sneh, Carina Gileadi, N. Strizhov, Noa Furman, I. Ishaaya, Shinkichi Tawata, N. Chejanovsky, Ehud Gazit, A. Navon, M. Kehat, Ephraim Cohen, E. Gershburg, Akinori Hirashima, M. Gurevitz, Takane Fujimori, C. Koncz, N. Zilberberg, Yoel Sasson, Itamar Glazer, I. Yamaguchi, M. Kostjukovsky, Hanokh Czosnek, B. Raccah, H. Rivkin, Miriam Eliyahu, I. Seltzer, Sonja Farkash, Satoshi Nakamura, Vivian Fridman, Miriam Altstein, Dvir Taler, Ezra Dunkelblum, J. Schell, Tetsu Ando, Y. Elad, T. Yoshimoto, Samir Droby, E. Shaaya, Shinzo Kagabu, Annie Fenigstein, Isaac Barash, K. R. S. Ascher, Yael Heifetz, A. R. Horowitz, Abraham Sztejnberg, T. Motoyama, D. Veierov, Uri Hanania, Yigal Cohen, Mitsuro Hyakumachi, Yechiel Shai, Mohammad Zeidan, Toshihiro Kajiwara, C. Gilon, D. Stockholm, I. Yamamoto, T. Fujita, M. Keller, Shalom W. Applebaum, Moshe Lapidot, Orna Ben-Aziz, A. Shani, K. Ohsawa, Edo Chalutz, Irit Schafler, Shai Morin, N. Aharonson, I. S. Ben-Ze’ev, Adi Avni, Baruch Sneh, Ada Rafaeli, Galina Gindin, and E. Kleter
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Agriculture ,business.industry ,Agroforestry ,Insect Science ,Ecology (disciplines) ,Plant Science ,Biology ,business ,Biotechnology - Published
- 1997
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95. Quantitative ultrasound for the assessment of bone status
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Hamanaka Y, I Yamamoto, Matsushita R, I Yuu, R Morita, Takada M, Ohta T, and K Masuda
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Adult ,medicine.medical_specialty ,Bone density ,Endocrinology, Diabetes and Metabolism ,Osteoporosis ,MEDLINE ,Bone Density ,Risk Factors ,Internal medicine ,medicine ,Humans ,Mass Screening ,Osteoporosis, Postmenopausal ,Mass screening ,Aged ,Ultrasonography ,Aged, 80 and over ,Hip Fractures ,business.industry ,Middle Aged ,medicine.disease ,Rheumatology ,Quantitative ultrasound ,Fractures, Spontaneous ,Broadband ultrasound attenuation ,Orthopedic surgery ,Female ,Radiology ,business - Published
- 1997
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96. [Untitled]
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T. Ishihara, I Yamamoto, and B. K Yen
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Materials science ,Mechanical Engineering ,Reinforced carbon–carbon ,chemistry.chemical_element ,Tribology ,medicine.disease ,Nitrogen ,Rubbing ,chemistry ,Mechanics of Materials ,Desorption ,medicine ,General Materials Science ,Composite material ,Lubricant ,Vapours ,Water vapor - Abstract
This paper describes an investigation on the combined influence of environment and temperature on the tribological behaviour of a carbon–carbon (C/C) composite material with a particular reference to the interaction between water vapour and oxygen in air and the carbon surface. Experiments were conducted in nitrogen and air with a low-speed three-pins-on-disc apparatus and a high-energy ring-on-ring apparatus. Like conventional graphitic carbon materials, C/C composites exhibited a high friction and wear phenomenon, also known as “dusting”, in dry nitrogen from room temperature up to 700°C owing to the lack of lubricant gases and vapours in the environment. In ambient air, however, C/C composites exhibited three temperature-dependent tribological regimes. Abrupt increases in the friction at 150–200°C and 650–700°C marked the transitions between different regimes. The transition phenomena were explained in terms of the desorption of physisorbed water vapour and chemisorbed oxygen from the rubbing surface.
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- 1997
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97. Magnetic field sensing by an electrostrictive/magnetostrictive composite resonator
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Y. Shimada, I. Yamamoto, and N. Yoshizawa
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Resonator ,Transducer ,Materials science ,Nuclear magnetic resonance ,Electrostriction ,Field (physics) ,Acoustics ,Magnetostriction ,Sensitivity (control systems) ,Electrical and Electronic Engineering ,Inverse magnetostrictive effect ,Electronic, Optical and Magnetic Materials ,Magnetic field - Abstract
A magnetic field sensor made of an electrostrictive plate and magnetostrictive layers is investigated. Its response to an external field suggests that the sensor has sensitivity high enough to detect terrestrial field. An analysis to predict the basic behavior was developed. Deviation of the experiments from the theoretical curve was attributed to complicated domain structures. Performance of a feedback system to improve the characteristics is demonstrated. It is expected that the performance would be improved appreciably by fabricating them by a thin film process.
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- 2005
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98. Analytical detection system of mixed odor vapors using chemiluminescence-based gas sensor
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Masuo Nakagawa, N. Yamashita, Y. Yamashita, T. Wada, I. Yamamoto, K. Nishiyama, S. Kawabata, and K. Utsunomiya
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Analytical chemistry ,Temperature measurement ,complex mixtures ,Catalysis ,law.invention ,chemistry.chemical_compound ,Magazine ,law ,Materials Chemistry ,Acetone ,Potentiometric sensor ,Gas detector ,Electrical and Electronic Engineering ,Instrumentation ,Chemiluminescence ,Ethanol ,Mixed gas ,technology, industry, and agriculture ,Metals and Alloys ,food and beverages ,Condensed Matter Physics ,Electrochemical gas sensor ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Catalytic oxidation ,Odor - Abstract
A chemiluminescence(CL)-based gas sensor made of γ-Al2O3 emits CL during catalytic oxidation of a combustible odor vapor. The CL intensity is proportional to the concentration of ethanol or acetone vapor in air. The algebraic sum rule is applicable to the CL intensities by the mixed gas of these two kinds of vapors, when the sensor is heated above 450°C. The CL intensities are measured in periodic temperature cycles between 650 and 450°C. The concentrations of vapor components can be detected analytically by measuring total CL intensities during the high and low temperatures for air containing mixed vapors of various concentrations of ethanol below 400 ppm and acetone below 200 ppm.
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- 1996
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99. Dynamic Fracture Characteristics in Aluminum Casting Alloy
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Takayuki Kobayashi and I. Yamamoto
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Materials science ,Three point flexural test ,Mechanical Engineering ,Metallurgy ,Alloy ,engineering.material ,Condensed Matter Physics ,Strain rate dependency ,Mechanics of Materials ,engineering ,Fracture (geology) ,General Materials Science ,Composite material ,Tensile testing - Published
- 1996
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100. Downregulation of the PTH/PTHrP receptor by vitamin D3 in the osteoblast-like ROS 17/2.8 cells
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Gino V. Segre, Abdul B. Abou-Samra, A. Leung, Lin Y. Xie, and I. Yamamoto
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medicine.medical_specialty ,Physiology ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Molecular Sequence Data ,Down-Regulation ,Parathyroid hormone ,Antibodies ,Calcitriol ,Downregulation and upregulation ,Transcription (biology) ,Physiology (medical) ,Internal medicine ,Tumor Cells, Cultured ,medicine ,Animals ,Amino Acid Sequence ,RNA, Messenger ,Receptor ,Receptor, Parathyroid Hormone, Type 1 ,Messenger RNA ,Osteoblasts ,Chemistry ,Cell Membrane ,Osteoblast ,Peptide Fragments ,Rats ,Steroid hormone ,Endocrinology ,medicine.anatomical_structure ,Cell culture ,Receptors, Parathyroid Hormone ,hormones, hormone substitutes, and hormone antagonists - Abstract
Effects of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on the expression of the parathyroid hormone (PTH)/PTH-related peptide (rP) receptor protein and mRNA in ROS 17/2.8 cells were studied. Treatment of ROS 17/2.8 cells with 1,25(OH)2D3 caused time- and dose-dependent suppression of PTH/PTHrP receptor number and immunoreactivity. The effects required more than 24 h incubation with 1,25(OH)2D3 and were maximal by 72 h. The cells did not recover their PTH/PTHrP receptors even after 4 days of treatment with control medium. Treatment with low concentrations of 1,25(OH)2D3 (0.1 M) dramatically decreased the PTH/PTHrP receptor mRNA levels, which were maximal after 24 h of incubation. The half-life of the PTH/PTHrP receptor transcript, 6-8 h, was similar in control and 1,25(OH)2D3-treated cells, suggesting that 1,25(OH)2D3 acts in controlling transcription of the PTH/PTHrP receptor gene but does not change the degradation rate of the PTH/PTHrP receptor transcripts. These data indicate that 1,25(OH)2D3 has a potent inhibitory effect on the expression of the PTH/PTHrP receptor protein and mRNA in ROS 17/2.8 cells.
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- 1996
- Full Text
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