71 results on '"Kurihara, T"'
Search Results
2. Application of energy‐filtering electron microscopy (EFEM) for analysis of hydrogen peroxide and lignin in epidermal walls of cucumber leaves triggered by acibenzolar‐S‐methyl treatment prior to inoculation with Colletotrichum orbiculare
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Park, P., Kurihara, T., Nita, M., Ikeda, K., Inoue, K., and Ishii, H.
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ANALYSIS of hydrogen peroxide , *LIGNINS , *ELECTRON microscopy , *HYDROGEN peroxide , *PECTINS , *COLLETOTRICHUM , *VACCINATION , *CUCUMBERS - Abstract
Hydrogen peroxide (H2O2) and lignin induced by acibenzolar‐S‐methyl (ASM) during the expression of systemic acquired resistance (SAR) of cucumber plants against the fungus Colletotrichum orbiculare was analysed with electron microscopy and energy‐filtering electron microscopy (EFEM). ASM pretreatment consistently led to the blockage of appressorial penetration pegs into leaves at early stages after inoculation, whereas the fungus was able to grow into the vascular tissue after distilled water pretreatment. The blocked pegs, seen frequently at epidermal pectin layers in leaves of ASM‐treated plants, were surrounded by abundant electron‐dense amorphous material and dots. These were identified as lignin, based on their appearance and high reactivity with KMnO4. Lignin first appeared as an amorphous material at pectin layers, and then as dots in some areas of the material. The results showed that ASM caused SAR in leaves via faster formation of lignin within 1 day after inoculation. After CeCl3 treatment to detect H2O2, H2O2‐reactive products (cerium perhydroxides) were seen near ASM‐induced lignin formation sites in pectin layers. EFEM analysis showed that Ce and O were located at the same sites as the lignin dots, suggesting that lignin was associated with sources of H2O2 generation. The results indicate that the faster H2O2 generation and lignification induced by ASM were the potential causes of SAR. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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3. THz Induced Nonlinear Effects in Materials at Intensities above 26 GW/cm2.
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Woldegeorgis, A., Kurihara, T., Beleites, B., Bossert, J., Grosse, R., Paulus, G. G., Ronneberger, F., and Gopal, A.
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ELECTROOPTICS , *REFRACTIVE index measurement , *SEMICONDUCTORS , *NONLINEAR optics , *TERAHERTZ technology - Abstract
Nonlinear refractive index and absorption coefficient are measured for common semiconductor material such as silicon and organic molecule such as lactose in the terahertz (THz) spectral regime extending from 0.1 to 3 THz. Terahertz pulses with field strengths in excess of 4.4 MV/cm have been employed. Transmittance and the transmitted spectrum were measured with Z-scan and single shot noncollinear electro-optic pump-probe techniques. The THz-induced change in the refractive index (Δn) shows frequency-dependence and a maximum change of −0.128
at 1.37 THz in lactose and up to +0.169 at 0.15 THz in silicon was measured for a peak incident THz intensity of 26 GW/cm2. Furthermore, the refractive index variation shows a quadratic dependence on the incident THz field, implying the dominance of third-order nonlinearity. [ABSTRACT FROM AUTHOR] - Published
- 2018
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4. Non-destructive measurement of the beryllium thickness of the iBNCT neutron-generation target using negative muons.
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Sato, M., Kurihara, T., Naito, F., Sugimura, T., Kumada, H., Tanaka, S., Ohba, T., and Nagura, N.
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MUONS , *BORON-neutron capture therapy , *THICKNESS measurement , *NEUTRONS , *LINEAR accelerators , *NEUTRON flux , *COPPER - Abstract
Accelerator-based boron neutron capture therapy (BNCT) has recently been studied by several researchers. In BNCT, a neutron-generation target is an important component because an intense neutron flux of more than 109n/cm2/s is required to complete medical treatments within an acceptable treatment time. In the Ibaraki BNCT (iBNCT) project, a proton linear accelerator (linac) consisting of a 3-MeV radio-frequency quadrupole and an 8-MeV drift-tube linac based on J-PARC linac techniques was used. As for the neutron-generation target, beryllium was adopted with an incident proton energy of 8 MeV. The target has a three-layer structure fabricated using hot-isostatic pressing (HIP). The first layer consists of 0.5 mm-thick beryllium, which is slightly shorter than the 8-MeV proton range in beryllium for neutron generation. The second is a 0.5 mm-thick palladium, which was selected owing to its durability against blistering, and the third is a 10 mm-thick copper for heat removal purposes with cooling water circulation. The thickness of the beryllium is very important because a shortage of thickness reduces the yield of neutrons, while an excess of thickness results in damage by stopped protons owing to a blistering effect. Despite its importance, this thickness has not yet been confirmed because it is not realistic to measure it destructively in terms of the construction cost of the iBNCT target; thus, a non-destructive measurement is desirable. This paper describes a method for measuring the thickness of the beryllium layer of a mockup of an iBNCT neutron target, which was constructed in the same way as the actual iBNCT, in a non-destructive manner using negative muon X-rays. The experiment was performed in the J-PARC MLF muon facility, and the obtained thickness was 0.48 ± 0.02 mm, which corresponds to the designed value of 0.50 ± 0.05 mm. [ABSTRACT FROM AUTHOR]
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- 2023
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5. Application of Terahertz Field Enhancement Effect in Metal Microstructures.
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Nakajima, M., Kurihara, T., Tadokoro, Y., Kang, B., Takano, K., Yamaguchi, K., Watanabe, H., Oto, K., Suemoto, T., and Hangyo, M.
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TERAHERTZ spectroscopy , *LIQUID crystals , *METAL microstructure , *PYROELECTRIC detectors , *BOLOMETERS , *MAGNETIC materials - Abstract
Applications of high-field terahertz pulses are attractive in physics and terahertz technology. In this study, two applications related to high-intensity terahertz pulses are demonstrated. The field enhancement effect by subwavelength metallic microstructures is utilized for terahertz excitation measurement. The spin precession dynamics in magnetic materials was induced by a terahertz magnetic field. Spin precession was amplified by one order of magnitude in amplitude by the enhanced magnetic terahertz field in orthoferrite ErFeO with metal microstructures. The induced spin dynamics was analyzed and explained by LLG-LCR model. Moreover, a detection method for terahertz pulses was developed using a cholesteric liquid crystal at room temperature without any electronic devices. The beam profile of terahertz pulses was visualized and compared to other methods such as the knife edge method using pyroelectric detector and micro-bolometer array. The liquid crystal terahertz imager is very simple and has good applicability as a portable terahertz-sensing card. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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6. Neutron target research and development for BNCT: direct observation of proton induced blistering using light-polarization and reflectivity changes.
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Kurihara, T., Kobayashi, H., Matsumoto, H., and Yoshioka, M.
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PROTONS , *FABRICATION (Manufacturing) , *NUCLEAR physics , *ANALYTICAL radiochemistry , *NUCLEAR chemistry - Abstract
The blistering problem due to high power proton irradiation is a crucial issue for any neutron generation target. When a proton beam irradiates a metal, the protons stopped inside capture free electrons in the metal to form a hydrogen gas. Eventually, blisters and/or flakes appear on the surface as the pressure of the hydrogen gas rises enough to cause ruptures. An experimental setup for observation of the metal surface that would have high sensitivity and high spatial resolution was proposed, designed and implemented. The system observes light-polarization and reflectivity and has successfully detected blistering surface dynamics. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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7. Enhanced spin-precession dynamics in a spin-metamaterial coupled resonator observed in terahertz time-domain measurements.
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Kurihara, T., Nakamura, K., Yamaguchi, K., Sekine, Y., Saito, Y., Nakajima, M., Oto, K., Watanabe, H., and Suemoto, T.
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PRECESSION , *RESONATORS , *METAMATERIALS , *ORTHOFERRITES , *SUBMILLIMETER waves , *TERAHERTZ time-domain spectroscopy - Abstract
We demonstrate enhancement of the spin precession of orthoferrite ErFeO3 using the magnetic near-field produced by a split-ring resonator (SRR), using the terahertz pump-optical Faraday probe measurement. The precession amplitude was enhanced by ∼ 8 times when the resonance frequency of spin precession was close to the magnetic resonance of SRR. The time evolution of spin precession was successfully reproduced by a coupled spin- and SRR-resonance model mediated by the magnetic near-field. It is suggested that optimization of the metamaterial structure would further increase the enhancement factor, leading to the nonlinear control of spin dynamics using terahertz radiation. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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8. Alterations in intramuscular water movement associated with mechanical changes in human skeletal muscle fibers: an evaluation using magnetic resonance diffusion-weighted imaging and B-mode ultrasonography.
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Yanagisawa O, Kurihara T, Fukubayashi T, Yanagisawa, Osamu, Kurihara, Toshiyuki, and Fukubayashi, Toru
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MEDICAL imaging systems , *MAGNETIC resonance , *DIFFUSION magnetic resonance imaging , *ULTRASONIC imaging , *MUSCLES - Abstract
Background: Intramuscular water movement is expected to be affected by the mechanical changes of the muscle fibers. However, the effect of changes in fiber length (FL) and pennation angle (PA) on the water movement has not been sufficiently investigated in human skeletal muscles.Purpose: To determine the relationship between intramuscular water movement and the mechanical changes in human muscle fibers.Material and Methods: Axial magnetic resonance diffusion-weighted images of the right leg (eight men) were taken using a 1.5-Tesla device with the ankle joint maximally dorsiflexed and maximally plantar flexed. The apparent diffusion coefficient (ADC) values of both the dorsiflexors (the superficial and deep parts of the tibialis anterior) and the plantar flexors (medial gastrocnemius and soleus) were calculated along three orthogonal axes (S-I: superior-to-inferior, A-P: anterior-to-posterior, and R-L: right-to-left). FL and PA of both muscle groups were also calculated from longitudinal B-mode ultrasound images with the ankle joint maximally dorsiflexed and plantar flexed.Results: There was a significant increase in the ADC in superficial (P < 0.05) and deep (P < 0.05) parts of the dorsiflexors in the S-I direction when the ankle was plantar flexed and in the A-P and R-L directions when the ankle was dorsiflexed (P < 0.05). The plantar flexors showed significantly elevated ADC in the S-I direction when the ankle was dorsiflexed (P < 0.05), and in the A-P and R-L directions when the ankle was plantar flexed (P < 0.05). The dorsiflexors also showed significantly increased PA and decreased FL values when the ankle was dorsiflexed (P < 0.05). The plantar flexors displayed similar morphological changes when the ankle was plantar flexed (P < 0.05).Conclusion: Water diffusion is affected by structural changes in the long axis of the muscle fibers, namely the changes in PA and FL. [ABSTRACT FROM AUTHOR]- Published
- 2011
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9. Seventeen-year clinical outcome of schizophrenia in Bali
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Kurihara, T., Kato, M., Reverger, R., and Tirta, I.G.R.
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PEOPLE with schizophrenia , *SCHIZOPHRENIA , *HEALTH outcome assessment , *MORTALITY , *FOLLOW-up studies (Medicine) , *PREDICTION (Psychology) - Abstract
Abstract: Objective: To examine the 17-year clinical outcome of schizophrenia and its predictors in Bali. Methods: Subjects were 59 consecutively admitted first-episode schizophrenia patients. Their clinical outcome was evaluated by standardized symptomatic remission criteria based on Positive and Negative Syndrome Scale (PANSS) scores and operational functional remission criteria at 17-year follow-up. The standardized mortality ratio (SMR) over 17 years was also calculated as another index of clinical outcome. Results: Among these 59 patients, 43 (72.9%) could be followed-up, 15 (25.4%) had died, and one (1.7%) was alive but refused to participate in the study. Combined remission (i.e. symptomatic and functional remission) was achieved in 14 patients (23.7% of original sample). Duration of untreated psychosis (DUP) was a significant baseline predictor of combined remission. Mean age at death of deceased subjects was 35.7, and SMR was 4.85 (95% CI: 2.4–7.3), indicating that deaths were premature. Longer DUP was associated with excess mortality. Conclusions: The long-term outcome of schizophrenia in Bali was heterogeneous, demonstrating that a quarter achieved combined remission, half were in nonremission, and a quarter had died at 17-year follow-up. DUP was a significant predictor both for combined remission and mortality. [Copyright &y& Elsevier]
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- 2011
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10. Development of tribo-simulator for hot stamping
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Yanagida, A., Kurihara, T., and Azushima, A.
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SIMULATION methods & models , *FOIL stamping , *FRICTION , *TEMPERATURE effect , *FINITE element method , *EMULSIONS , *PRESSURE , *QUANTITATIVE research - Abstract
Abstract: Coefficients of friction were measured at elevated temperatures using a hot flat strip drawing test machine newly developed by the authors for the purpose of confirming the coefficients of friction used for the FEM simulation of hot stamping. To examine the functions of the tribo-simulator, the coefficients of friction are measured using hot rolling oil with an emulsion, which is supplied continuously, while varying the drawing speed, drawing pressure and temperature. From the experimental results, it was shown that the coefficient of friction in hot stamping can be measured using this tribo-simulator. The measured coefficients of friction can be used as values in the FEM simulation of hot stamping. Moreover, the tribological behavior at the interface between the die and strip in hot stamping can be evaluated from the coefficient of friction, because it is one of the quantitative values used to represent the tribological behavior between the die and blank. [Copyright &y& Elsevier]
- Published
- 2010
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11. Evaluation of self-organized diffusion barrier continuity on a nano-architectural silica thin film with two-dimensionally connected cage-like pores using positronium time of flight spectroscopy
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Tanaka, H.K.M., Kurihara, T., Nishiyama, N., Maruo, T., and Mills, A.P.
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DIFFUSION , *POSITRONIUM , *THIN films , *SILICON compounds - Abstract
Abstract: Positronium time of flight (Ps-TOF) was measured by implanting slow positron pulses at variable energies into a nano-architectural silica thin film with two-dimensionally connected cage-like pores to investigate a continuity of the self-organized extremely thin diffusion barrier between the pores. By comparing a capped and open-pored low-k film, we found a Ps-TOF spectrum with positron implantation energy of 0.2keV that reflects the sample structure is consistent with an open pore fraction η <1.7·×10−6 of the diffusion barrier. [Copyright &y& Elsevier]
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- 2006
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12. Eleven-year clinical outcome of schizophrenia in Bali.
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Kurihara, T., Kato, M., Reverger, R., and Tirta, I. G. R.
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SCHIZOPHRENIA , *PSYCHOSES , *PATHOLOGICAL psychology , *PATIENTS , *SOCIAL adjustment , *SOCIAL psychology - Abstract
Objective: To contrast the short-term and long-term outcome of schizophrenia in Bali. Method: The clinical outcomes of 46 schizophrenic patients (DSM-IV-TR) consecutively admitted to Bangli Mental Hospital were evaluated by Positive and Negative Syndrome Scale (PANSS) and Eguma's Social Adjustment Scale (ESAS) at a 11-year follow-up, which was subsequent to a 5-year follow-up. Results: Neither the PANSS score nor the ESAS score were significantly different, and there was a significant correlation between the two follow-up data. Subjects categorized into either the best or worst outcome group at the 5-year follow-up tended to be classified into the same category at the 11-year follow-up more often than those who were categorized into the medium outcome groups at the 5-year follow-up. Conclusion: The 5-year outcome of schizophrenia strongly predicted the 11-year outcome, especially for subjects who had gone into either a remissive or severe deterioration state within 5 years. [ABSTRACT FROM AUTHOR]
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- 2005
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13. Medium factors of electrical insulation systems in high temperature superconducting power apparatus with coil structure for equivalent ac withstand voltage test at room temperature
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Hara, M., Kurihara, T., Nakano, R., and Suehiro, J.
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LIQUID nitrogen , *ELECTRIC conductivity , *HIGH temperatures , *ELECTRIC breakdown - Abstract
Abstract: Equivalent insulation test voltage at room temperature of high temperature superconducting (HTS) power apparatus with coil structure for power frequency withstand voltage tests is discussed based on medium factors of insulation weak parts in electrical insulation elements of the HTS power apparatus. Uniform and non-uniform field gaps, triple junction and solid insulator surface are selected as the insulation weak parts, and their medium factors are theoretically and experimentally calculated as the ratio of partial discharge (PD) inception or direct-breakdown voltages in liquid nitrogen or cryogenic nitrogen gas to those in atmospheric air at room temperature. The results show that the type of insulation weak part affects the relationships between the medium factor and the gap length between electrodes as well as the state of cryogenic surrounding medium. These medium factors are compared with the medium factor of a coil-to-coil insulation element of HTS pancake coils that contains some of the insulation weak parts, and it is verified that the medium factor of the coil-to-coil insulation element can be obtained by using that of triple junction or solid insulator surface. Finally, a selection method of a significant unique medium factor is discussed to determine the equivalent insulation test voltage at room temperature for the confirmation of the insulation reliability of all the parts of the HTS apparatus. [Copyright &y& Elsevier]
- Published
- 2005
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14. Determination method of equivalent insulation test voltage at room temperature for high temperature superconducting power apparatus with coil structure
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Hara, M., Kurihara, T., Nishioka, T., Suehiro, J., and Okamoto, H.
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SUPERCONDUCTORS , *HIGH voltages , *LIQUID nitrogen , *ELECTRIC insulators & insulation - Abstract
This paper deals with the determination method of the equivalent insulation test voltage at room temperature that secures the reliability of the cryogenic electrical insulation of the high temperature superconducting (HTS) power apparatus. The high voltage test is related to the apparatus with coil structure at the stages of its development, manufacturing and shipment. In the test method, the equivalent insulation test voltage at room temperature is derived from the standard test voltage at cryogenic temperature, based on the idea that the HTS power apparatus should be operated without partial discharges (PDs). The conversion factor between the two voltages is given by the product of the two medium factors, i.e. the one relating to the potential distribution along the coil winding and the other relating to the PD inception condition at the weakest part in the electrical insulation system. In order to determine the latter factor concerned with the non-linear phenomena against electrical stresses, the PD inception voltages at cryogenic and room temperatures are theoretically and experimentally estimated for modeled turn-to-turn insulation system. The results show that both estimated and measured values are in fairly good agreement and the proposed method is useful for the equivalent high voltage test at room temperature for the HTS power apparatus. [Copyright &y& Elsevier]
- Published
- 2004
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15. Adaptations of subtropical Venus clams to predation and desiccation: endurance of Gafrarium tumidum and avoidance of Ruditapes variegatus.
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Kurihara, T.
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BIVALVES , *HIGH temperatures , *OCEAN circulation , *HEAT , *CRABS , *MARINE biology - Abstract
Intertidal endobenthic bivalves are often dislodged from sediments by hydrodynamic forces. As a result, they encounter the dangers of predation and desiccation, which are generally harsh near the sediment surface. To cope with such dangers, the bivalves possibly possess: (1) a strong body to endure predation and desiccation stress, (2) quick mobility to avoid the stresses, or (3) a high growth rate for attaining a size refuge. The present study examined which of these modes are adopted by the subtropical cobbled-shore Venus clams Gafrarium tumidum (Röding, 1798) and Ruditapes variegatus (Sowerby, 1852), revealing the following interspecific differences. (1) G. tumidum survived better than R. variegatus did in harsh experimental conditions, namely: the experimental cages exposed to predation and desiccation on a cobbled shore; a laboratory aquarium with a predatory crab Scylla serrata; and ovens with high temperatures (27°C and 34°C). (2) R. variegatus was more mobile than G. tumidum was, digging into the sediment on a cobbled shore more rapidly at both high and low tides. (3) The two species with shell lengths 20–30 mm showed similar growth rates (median: -0.2 to 44.5 μm day-1) in seasonal mark–recapture surveys over 2 years. Overall, to cope with the dangers of predation and desiccation G. tumidum appears to have a strong body, while R. variegatus displays rapid mobility, and neither species seems to attain a size refuge through rapid growth. Such species-specific modes are discussed in relation to the interspecific differences found in shell morphology. [ABSTRACT FROM AUTHOR]
- Published
- 2003
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16. PD Characteristics in an Air-Filled Void at Room Temperature under Superimposed Sinusoidal Voltages.
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Kurihara, T., Tsuru, S., Imasaka, K., Suehiro, J., and Hara, M.
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ELECTRIC discharges , *ELECTRIC charge - Abstract
Presents a study which investigated partial discharge in an artificial air-filled void under superimposed sinusoidal voltages to clarify the effect of voltage superposition. Experimental setup and procedures; Results; Discussion.
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- 2001
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17. Outcome of schizophrenia in a non‐industrialized society: comparative study between Bali and Tokyo.
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Kurihara, T., Kato, M., Reverger, R., and Yagi, G.
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SCHIZOPHRENIA , *PSYCHOSES - Abstract
Objective: The aim of the present study was to contrast the outcome of schizophrenic patients between Bali and Tokyo, the former being a non‐industrialized society and the latter an industrialized society in Asia. Method: A total of 51 Balinese schizophrenics and 40 schizophrenics in Tokyo were evaluated by five outcome measures at a 5‐year follow‐up. Results: No significant difference was found in the mean scores of the Positive and Negative Syndrome Scale, Eguma's Social Adjustment Scale and the re‐admission rates between the subjects in the two sites. The cumulative length of stay in hospital during the 5‐year period was significantly shorter in Bali. The percentage of subjects on psychiatric medication at the follow‐up was significantly lower in Bali than that in Tokyo. Conclusion: Although the clinical outcome of schizophrenics in Bali was not superior to that in Tokyo, the subjects in Bali tended to be able to live in society without neuroleptic medication. [ABSTRACT FROM AUTHOR]
- Published
- 2000
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18. PRESSOR RESPONSES TO SEROTONIN INJECTED INTO THE NUCLEUS TRACTUS SOLITARIUS OF SPRAGUE-DAWLEY RATS AND SPONTANEOUSLY HYPERTENSIVE RATS.
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Tsukamoto, K., Kurihara, T., Nakayama, N., Isogai, O., Ito, S., Komatsu, K., and Kanmatsuse, K.
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SEROTONIN , *SOLITARY nucleus - Abstract
Previous studies in rats have shown that injection of nanomoles of serotonin (5-hydroxytryptamine; 5HT) into the nucleus tractus solitarius (NTS) acts on 5HT3 receptors to increase arterial pressure (AP). We investigated the effect of 5HT in Sprague-Dawley (SD) rats and in spontaneously hypertensive rats (SHR). Injection of nanomoles of 5HT into the NTS of chloralose-anesthetized SD rats increased AP. This effect was inhibited by prior injection of 5HT3 receptor antagonist ondansetron. The GABAA receptor antagonist bicuculline did not inhibit the effect of 5HT. Bilateral injection of 5HT or ondansetron did not affect the baroreflex sensitivity. Bilateral injection of ondansetron did not alter AP. The pressor effect of 5HT was exaggerated in SHR. These results suggest that stimulation of 5HT3 receptors in the NTS increases AP independently of activation of GABAA receptors and the baroreflex sensitivity. Furthermore, this serotonergic system is supersensitive in the NTS of SHR. [ABSTRACT FROM AUTHOR]
- Published
- 2000
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19. Geochemistry and Sr–Nd isotopic composition of meta-gabbros from the Omi serpentinite mélange, Niigata, SW Japan: Evidence for subduction erosion in an immature early Paleozoic arc-trench system in proto-Japan.
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Satish-Kumar, M., Kurihara, T., Shishido, R., Yoshida, T., Takahashi, T., and Nohara-Imanaka, R.
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GEOCHEMISTRY , *EROSION , *PALEOZOIC Era , *SERPENTINITE , *SUBDUCTION , *SCHISTS , *ACCRETIONARY wedges (Geology) , *SUBDUCTION zones - Abstract
The Renge Belt is a rare subduction-related metamorphic belt that contains blocks of eclogites, meta-gabbros, schists and other rocks in a serpentinite mélange that formed in the early-to-middle Paleozoic of proto-Japan. We report here a detailed geochemical and Sr–-Nd isotope study of two major groups of rocks within the Omi serpentine mélange: 1. medium-grade metamorphosed blocks of meta-gabbros, and 2. high-pressure low-temperature eclogites and mafic schists. Bulk rock geochemistry of the meta-gabbros reveals that they have prominent Nb, Ta and Ti negative anomalies, suggesting an arc origin. In contrast, the eclogites, and mafic schists have trace element spider diagrams and REE patterns that resemble modern oceanic crust. The Sr– Nd isotopic compositions also show concomitant variations with a highly depleted source for the meta-gabbros (εNd values of +1.3 − +9.6 and Sr i ratios of 0.70301–0.70460) compared with a MORB/OIB-like source of the eclogites and mafic schists (εNd values of −1.94 – +4.83), although the latter have Sr isotopes variably affected by seawater interaction (Sr i ratios of 0.70518–0.71050). Altogether, the geochemical features suggest that the meta-gabbros were part of a magmatic arc, which developed in the Cambrian and was tectonically eroded and subducted together with oceanic crust and sediments in the Devonian–Carboniferous. The ages of detrital zircons in the pelitic schist (3200–600 Ma) suggests that the South China Craton and northeastern fringes of Gondwana were potential source regions and that the sedimentation occurred most likely in a trench. The abundant Early Paleozoic (peak around ca. 470 Ma) detrital zircons were derived from an active subduction-related arc. The protoliths of meta-gabbros are lower crustal equivalents of an infant arc, which was subducted via subduction erosion in the Devonian–Carboniferous and reached a HP metamorphic depth in the Tournasian. Our results suggest that the formation of proto-Japan was related to the initiation of intra-oceanic arc as early as Cambrian. Following tectonic erosion, the remnant mafic rocks were amalgamated with trench-fill sediments during incorporation in an accretionary complex. Subduction erosion was active where sediment supply was low and where the arc was immature. Subduction of oceanic crust was continuing to at least the middle Carboniferous, when the eclogites and blueschists were formed and later exhumed along with the meta-gabbros in serpentinite diapirs in the mid–late Paleozoic. [Display omitted] • Meta-gabbros in sperpentinite mélange are of magmatic arc origin • Eclogites and mafic schists are remnants of oceanic crust • Subduction erosion of arc rocks in Paleozoic Japan • Early-Middle Paleozoic subduction in East Asia initiated with immature arc [ABSTRACT FROM AUTHOR]
- Published
- 2021
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20. Subharmonic lock-in detection and its optimization for femtosecond noise correlation spectroscopy.
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Weiss, M. A., Herbst, F. S., Eggert, S., Nakajima, M., Leitenstorfer, A., Goennenwein, S. T. B., and Kurihara, T.
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FEMTOSECOND pulses , *SIGNAL-to-noise ratio , *MAGNONS , *ACQUISITION of data , *DEMODULATION - Abstract
Although often viewed as detrimental, fluctuations carry valuable information about the physical system from which they emerge. Femtosecond noise correlation spectroscopy (FemNoC) has recently been established to probe the ultrafast fluctuation dynamics of thermally populated magnons by measurement of their amplitude autocorrelation. Subharmonic lock-in detection is the key technique in this method, allowing us to extract the pulse-to-pulse polarization fluctuations of two femtosecond optical pulse trains transmitted through a magnetic sample. Here, we present a thorough technical description of the subharmonic demodulation technique and the FemNoC measurement system. We mathematically model the data acquisition process and identify the essential parameters that critically influence the signal-to-noise ratio of the signals. Comparing the model calculations to real datasets allows validating the predicted parameter dependences and provides a means to optimize FemNoC experiments. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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21. 74P Comprehensive transcriptome analysis of endoplasmic reticulum stress in osteosarcomas.
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Suehara, Y., Kurihara, T., Hayashi, T., Sano, K., Sasa, K., Kubota, D., Akaike, K., Okubo, T., Kim, Y., and Saito, T.
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TRANSCRIPTOMES , *ENDOPLASMIC reticulum , *OSTEOSARCOMA - Published
- 2020
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22. Rendezvous Technique Using Double Balloon Endoscope for Removal of Multiple Intrahepatic Bile Duct Stones in Hepaticojejunostomy After Living Donor Liver Transplant: A Case Report.
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Kimura, K., Kudo, K., Kurihara, T., Yoshiya, S., Mano, Y., Takeishi, K., Itoh, S., Harada, N., Ikegami, T., Yoshizumi, T., and Ikeda, T.
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CHOLANGITIS , *INTRAHEPATIC bile ducts , *LIVER transplantation - Abstract
Abstract Cholangitis is a major complication following transplantation. We report a living donor liver transplant (LDLT) patient with cholangitis due to multiple stones in the intrahepatic bile duct during hepaticojejunostomy anastomosis, who was successfully treated with the rendezvous technique using double balloon endoscope. A 64-year-old woman underwent LDLT with right lobe graft and hepaticojejunostomy for Wilson disease. There was bile leakage with biliary peritonitis, which was treated conservatively after transplant. Two years after surgery, she developed reiterated cholangitis due to stenosis of hepaticojejunostomy anastomosis and multiple stones in the intrahepatic bile ducts. Percutaneous transhepatic biliary drainage was performed. The size of the drainage tube was increased, and the anastomotic area was dilated in a stepwise manner using a balloon catheter. The stones were crushed and lithotomy was performed using electronic hydraulic lithotripsy through cholangioscopy. Finally, lithotomy was performed for the remaining stones through endoscopic retrograde cholangiography with the rendezvous technique using the double balloon endoscope. Rendezvous approach with percutaneous transhepatic biliary drainage and double balloon endoscopic retrograde cholangiography was an effective treatment for the multiple intrahepatic stones in hepaticojejunostomy following LDLT with right lobe graft. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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23. Examination of changes in TGF-beta1 and KL-6 expression over time in patients with chronic hepatitis C by AT-II receptor blocker therapy.
- Author
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Kurihara T, Maeda A, Shigemoto M, Yamashita K, Kurihara, Takeshi, Maeda, Atsushi, Shigemoto, Mutsuo, and Yamashita, Katsuko
- Published
- 2005
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24. Preferred foot strategy for sprint initiation in children.
- Author
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Tottori, N., Kurihara, T., Otsuka, M., Cesar, G., and Isaka, T.
- Subjects
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FOOT movements , *CHILD psychology , *LIKES & dislikes , *SPRINTING , *HUMAN locomotion - Published
- 2015
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25. Dielectric probe for scattering-type terahertz scanning near-field optical microscopy.
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Kurihara, T., Yamaguchi, K., Watanabe, H., Nakajima, M., and Suemoto, T.
- Subjects
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NEAR-field microscopy , *DIELECTRIC properties , *DIELECTRICS , *DIELECTRIC measurements , *SCANNING probe microscopy - Abstract
Dielectric material was used as the probe material for a scattering-type terahertz scanning near-field optical microscope (THz S-SNOM). It was found that the dielectric probe exhibits a strong near-field scattering signal with an amplitude comparable to that of the metallic probe. The behavior of the electric near-field around the tip was calculated using the finite-difference time-domain method, showing the field enhancement comparable to that of the metallic probe. The dielectric probe also exhibited a faster temporal response compared to the response of the metallic probe. Introduction of a non-metallic probe would enlarge the application field of the THz S-SNOM technique. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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26. Effects of prior osteoporosis treatment on the treatment response of romosozumab followed by denosumab in patients with postmenopausal osteoporosis.
- Author
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Ebina, K., Etani, Y., Tsuboi, H., Nagayama, Y., Kashii, M., Miyama, A., Kunugiza, Y., Hirao, M., Okamura, G., Noguchi, T., Takami, K., Goshima, A., Miura, T., Fukuda, Y., Kurihara, T., Okada, S., and Nakata, K.
- Subjects
- *
RESEARCH , *SCIENTIFIC observation , *DISEASES , *MONOCLONAL antibodies , *OSTEOPOROSIS , *TREATMENT effectiveness , *POSTMENOPAUSE , *BONE density , *LONGITUDINAL method - Abstract
Summary: In patients with postmenopausal osteoporosis, prior osteoporosis treatment affected the bone mineral density increase of following treatment with 12 months of romosozumab, although it did not affect that of following treatment with 12 months of denosumab after romosozumab. Purpose: To investigate the effects of prior osteoporosis treatment on the response to treatment with romosozumab (ROMO) followed by denosumab (DMAb) in patients with postmenopausal osteoporosis. Methods: In this prospective, observational, multicenter study, treatment-naïve patients (Naïve; n = 55) or patients previously treated with bisphosphonates (BP; n = 37), DMAb (DMAb; n = 45) or teriparatide (TPTD; n = 17) (mean age, 74.6 years; T-scores of the lumbar spine [LS] − 3.2 and total hip [TH] − 2.6) were switched to ROMO for 12 months, followed by DMAb for 12 months. Bone mineral density (BMD) and serum bone turnover markers were evaluated for 24 months. Results: A BMD increase was observed at 12 and 24 months in the following patients: Naïve (18.2% and 22.0%), BP (10.2% and 12.1%), DMAb (6.6% and 9.7%), and TPTD (10.8% and 15.0%) (P < 0.001 between the groups at both 12 and 24 months) in LS and Naïve (5.5% and 8.3%), BP (2.9% and 4.1%), DMAb (0.6% and 2.2%), and TPTD (4.3% and 5.4%) (P < 0.01 between the groups at 12 months and P < 0.001 at 24 months) in TH, respectively. The BMD increase in LS from 12 to 24 months was negatively associated with the levels of bone resorption marker at 24 months. Incidences of major fragility fractures for the respective groups were as follows: Naïve (5.5%), BP (16.2%), DMAb (11.1%), and TPTD (5.9%). Conclusions: Previous treatment affected the BMD increase of following treatment with ROMO, although it did not affect that of following treatment with DMAb after ROMO. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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- View/download PDF
27. Evaluation of human muscle hardness after dynamic exercise with ultrasound real-time tissue elastography: A feasibility study
- Author
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Yanagisawa, O., Niitsu, M., Kurihara, T., and Fukubayashi, T.
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- *
EXERCISE physiology , *MUSCLES , *HARDNESS , *ULTRASONIC imaging , *BIOMEDICAL transducers , *PARAMETER estimation - Abstract
Aim: To assess the feasibility of ultrasound real-time tissue elastography (RTE) for measuring exercise-induced changes in muscle hardness and to compare the findings of RTE with those of a tissue hardness meter for semi-quantitative assessment of the hardness of exercised muscles. Materials and methods: Nine male participants performed an arm-curl exercise. RTE measurements were performed by manually applying repetitive compression with the transducer on the scan position before exercise, immediately after exercise, and at 30min after exercise; strain ratios between muscle and a reference material (hydrogel) were calculated (muscle strain/material strain). A tissue hardness meter was also used to evaluate muscle hardness. The intraclass correlation coefficients (ICCs) for the three repeated measurements at each measurement time were calculated to evaluate the intra-observer reproducibility of each technique. Results: Immediately after exercise, the strain ratio and the value obtained using the tissue hardness meter significantly decreased (from 1.65 to 1.35) and increased (from 51.8 to 54.3), respectively. Both parameters returned to their pre-exercise value 30min after exercise. The ICCs of the RTE (and the ICCs of the muscle hardness meter) were 0.971 (0.816) before exercise, 0.939 (0.776) immediately after exercise, and 0.959 (0.882) at 30min after exercise. Conclusion: Similar to the muscle hardness meter, RTE revealed the exercise-induced changes of muscle hardness semi-quantitatively. The intra-observer reproducibility of RTE was very high at each measurement time. These findings suggest that RTE is a clinically useful technique for assessing hardness of specific exercised muscles. [Copyright &y& Elsevier]
- Published
- 2011
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28. Distribution of hepatitis B viral genotypes and mutations in the core promoter and precore regions in acute forms of liver disease in patients from Chiba, Japan.
- Author
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Imamura T, Yokosuka O, Kurihara T, Kanda T, Fukai K, Imazeki F, and Saisho H
- Subjects
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LIVER diseases , *HEPATITIS B virus , *HEPATITIS viruses - Abstract
BACKGROUND: Although it has been reported that different hepatitis B virus (HBV) genotypes induce different clinical characteristics in patients with chronic liver diseases (CLD), there have been few reports that have detailed the distribution of HBV genotypes in acute forms of liver disease. METHODS: HBV genotypes were determined in 61 patients who had acute forms of liver disease (45 had acute self limited hepatitis (AH) and 16 had fulminant hepatitis (FH)) and in 531 patients with CLD, including 19 patients with severe acute exacerbation of CLD. We also analysed the enhancer II, core promoter, and precore region sequences for the presence of mutations. RESULTS: Expression of genotype B in patients with acute forms of liver disease was significantly greater than in those with CLD (39.3% v 11.7%, respectively; p<0.001). Furthermore, expression of genotype B was significantly greater in patients with FH than in those with AH (62.5% v 31.1%, respectively; p=0.027). The precore mutation A1896 and the core promoter mutation at nt 1753 and 1754 were found more frequently in FH than in AH, and genotype B was predominant in FH regardless of the presence of these mutations. CONCLUSIONS: HBV genotype B was found more frequently in patients with acute forms of liver disease than in patients with CLD, and more frequently in patients with FH than in those with AH. These results suggest that this HBV genotype may induce more severe liver damage than other viral genotypes, at least in patients from Chiba, Japan. [ABSTRACT FROM AUTHOR]
- Published
- 2003
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29. Selective gene expression using a DF3/MUC1 promoter in a human esophageal adenocarcinoma model.
- Author
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Gupta, V K, Park, J O, Kurihara, T, Koons, A, Mauceri, H J, Jaskowiak, N T, Kufe, D W, Weichselbaum, R R, and Posner, M C
- Subjects
- *
GENE expression , *GENE therapy , *TREATMENT of esophageal cancer - Abstract
The efficacy of replication-deficient adenoviral vectors in gene therapy is confined to the number of tumor cells the vector infects. To focus and enhance the therapeutic efficacy, we employed a conditionally replication-competent adenoviral vector with a tissue-specific promoter, DF3/MUC1, in a human esophageal adenocarcinoma model. Our results demonstrate that Ad.DF3.E1A.CMV.TNF (Ad.DF3.TNF) specifically replicates in Bic-1 (DF3-producing cells) and mediates an enhanced biologic effect due to increased TNF-α in the same DF3-producing cells. We also show that the increased TNF-α interacts with ionizing radiation to produce greater tumor regression and a greater delay in tumor regrowth in Bic-1 (DF3-producing cells) compared to Seg-1 (DF3 non-producers). Tumor cell targeting using conditionally replication-competent adenoviral vectors with tumor-specific promoters to drive viral replication and deliver TNF-α provides a novel approach to enhancing tumor radiosensitivity.Gene Therapy (2003) 10, 206–212. doi:10.1038/sj.gt.3301867 [ABSTRACT FROM AUTHOR]
- Published
- 2003
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30. A new positron lifetime spectrometer using a fast digital oscilloscope and BaF2 scintillators
- Author
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Saito, H., Nagashima, Y., Kurihara, T., and Hyodo, T.
- Subjects
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POSITRON annihilation , *SPECTROMETERS - Abstract
A new positron lifetime spectrometer has been constructed and tested. It consists of a state-of-the-art digital oscilloscope (LeCroy Wavepro 960) and scintillation detectors based on Hamamatsu H3378 (R2083Q) photomultiplier tubes and BaF2 scintillators. A very good time resolution is obtained with scintillators of commonly used sizes (28 mm in diameter, 10–20 mm thick) and wide energy window settings (40–50%). The time resolution of 144 ps full-width at half-maximum (FWHM) is achieved for the positron lifetime measurement, in which time differences are measured between the arrivals of a 1.27 MeV γ-ray from 22Na and one of the two positron annihilation γ-rays of 0.511 MeV. The time resolution is further improved with a ‘double-stop’ setup, where timing information carried by the positron annihilation γ-ray pair is combined to determine the time of the annihilation. The time resolution with this setup is 119 ps FWHM. This improvement is interpreted in terms of the energy deposit in the scintillation detectors by γ-rays. Applications of the new spectrometer to other scintillation timing measurements are also described. [Copyright &y& Elsevier]
- Published
- 2002
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31. Development of a hybrid collimator bonding tantalum and carbon-fiber-composite for SuperKEKB.
- Author
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Terui, S., Suetsugu, Y., Ishibashi, T., Natochii, A., Morikawa, Y., Shirai, M., Shibata, K., and Kurihara, T.
- Subjects
- *
HYBRID securities , *TANTALUM , *COLLIMATORS , *BEAM dynamics - Abstract
Collimators are required to reduce beam-induced backgrounds in the experiments in the SuperKEKB. Sudden beam losses that are not fully understood cause frequent beam impacts on collimators. SuperKEKB was operated with several collimator types and suffered from damage induced by sudden beam losses and from blow-up of the vertical beam size due to the collimator impedance. To address these issues, this study developed a new type of "hybrid collimator" for improved performance. Collimator damage events increase beam background (BG) noise. To address this limitation, we developed a hybrid collimator by bonding tantalum with a carbon-fiber-composite to form the collimator head that is less likely to have an adverse effect on the BG when the beam hits it. This hybrid collimator exhibited a low impedance and high durability. Particle-tracking simulations, and beam irradiation simulations were conducted, and subsequently, the hybrid collimator was installed in the SuperKEKB main ring. The designed hybrid collimator reduced the beam background noise and facilitated a low impedance and continuous stable operation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. 100 Poster Spotlight - Salivary metabolomics with artificial intelligence-based methods for breast cancer detection and subtype prediction.
- Author
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Murata, T., Yanagisawa, T., Kurihara, T., Kaneko, M., Ota, S., Enomoto, A., Tomita, M., Sugimoto, M., Sunamura, M., Hayashida, T., Jinno, H., and Kitagawa, Y.
- Subjects
- *
BREAST tumor diagnosis , *SALIVA analysis , *ARTIFICIAL intelligence , *BIOMARKERS , *CONFERENCES & conventions , *MACHINE learning , *METABOLOMICS , *EVALUATION - Published
- 2020
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- View/download PDF
33. Error-free programmable multi-wavelength pulse oscillator based on self-frequency shift of Raman soliton.
- Author
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Kato, M., Fujiura, K., and Kurihara, T.
- Subjects
- *
ELECTRIC oscillators , *SOLITONS , *RAMAN effect , *PICOSECOND pulses , *ULTRASHORT laser pulses - Abstract
An error-free wavelength tunable, low-noise (<-135 dBc/Hz: RIN) and high-wavelength stable programmable multi-wavelength pulse oscillator based on the self-frequency shift of Raman soliton has been demonstrated. Only selected multi-wavelength pulses with a tuning range of about 50 nm are generated with a clock rate of 9.95 GHz at each wavelength channel. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
34. Generation of super-stable 40 GHz pulses from Fabry-Perot resonator integrated with electro-optic phase modulator.
- Author
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Kato, M., Fujiura, K., and Kurihara, T.
- Subjects
- *
LASERS , *ELECTROOPTICS , *ELECTRONIC modulation , *FREQUENCY discriminators , *FOURIER series , *ELECTRONICS , *MATHEMATICS - Abstract
A simple technique for converting a continuous-wave laser beam into a stable pulse train with high repetition frequency is demonstrated. The generated train is based on the synthesis of its Fourier spectrum which is composed of higher-order sidebands produced by a FabryPerot resonator integrated with an electro-optic phase modulator. Super-stable 40 GHz, transform-limited optical pulses are successfully generated. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
35. Nonlinear optical properties of 2-adamantylamino-5-nitropyridine crystals.
- Author
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Tomaru, S., Matsumoto, S., Kurihara, T., Suzuki, H., Ooba, N., and Kaino, T.
- Subjects
- *
NONLINEAR optics , *PYRIDINE - Abstract
Reports that several organic materials with a bulky donor group have been developed for second-order nonlinear optics. 2-adamantylamino-5-nitropyridine crystal's second-order nonlinear optical coefficient; Second-harmonic measurements.
- Published
- 1991
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36. Intelligent cooling water control for a medical accelerator by application of fast feed-forward for future.
- Author
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Fang, Z., Sato, M., Futatsukawa, K., Fukui, Y., Naito, F., Sugimura, T., Obina, T., Honda, Y., Qiu, F., Michizono, S., Anami, S., Kobayashi, H., Kurihara, T., Miyajima, T., Ohba, T., and Nagura, N.
- Subjects
- *
BORON-neutron capture therapy , *NEUTRON capture , *INTELLIGENT control systems , *PROTON accelerators , *LINEAR accelerators - Abstract
An 8-MeV linear proton medical accelerator designed with a high RF duty operation is being developed at Ibaraki Neutron Medical Research Center for iBNCT (Ibaraki - Boron Neutron Capture Therapy). The reliability and stability of the cooling water control system has become one of the most important issues in realizing the medical application of the accelerator, which is designed considering high performance and low costs. However the previous cooling water control system with a commercial PID (Proportional–Integral–Differential) controller could not meet the operation requirements of the medical accelerator. Therefore, a new intelligent cooling water controller is successfully developed by application of Fast Feed-forward for Future (FFF). The detailed design of the intelligent cooling water control system and its great efficacy in improving accelerator operation is described in this paper. The stability of the cooling water temperature is improved greatly from the previous ± 0. 30 ° C to the current ± 0. 03 ° C. Moreover, the response time of cooling water control is decreased dramatically from the previous 5 min to approximately 20 s. Precise operation and an excellent auto-tuning of the RFQ (Radio Frequency Quadrupole LINAC) cavity are realized by using this stable and intelligent water control system. The beam transmittance is also improved slightly after a fine scan experiment with different settings of RF devices under stable acceleration operation. Finally, the RF startup time is also reduced by using this intelligent cooling water control system. Now the iBNCT accelerator operation is greatly improved with a very high reliability and stability. The accelerator will be operated as a practical medical therapy in late 2019. The technology developed in this intelligent cooling water control system will be very useful for the development of similar accelerators with high performance and low cost. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
37. Novel auto-startup technology for two cavities of a medical accelerator with one RF source.
- Author
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Fang, Z., Futatsukawa, K., Fukui, Y., Sato, M., Sugimura, T., Naito, F., Obina, T., Honda, Y., Qiu, F., Michizono, S., Anami, S., Kobayashi, H., Kurihara, T., Miyajima, T., Ohba, T., and Nagura, N.
- Subjects
- *
PROTON linear accelerator , *BORON-neutron capture therapy , *KLYSTRONS , *STABILITY (Mechanics) , *SOLID state physics - Abstract
Abstract At Ibaraki Neutron Medical Research Center, an 8-MeV proton linear accelerator is being developed for iBNCT (Ibaraki - Boron Neutron Capture Therapy), with the aim of achieving the highest possible performance at a low cost. In this accelerator, there are two RF cavities driven by only one high-power klystron as the RF source. A digital low-level RF system has been successfully implemented for the iBNCT accelerator, with very good RF field regulation. An effective multipurpose and smart tuner controller was also developed. Finally, a novel auto-startup technology for two cavities with one RF source was successfully developed. The time required for the RF startup process is greatly reduced from the conventional time of 30 min, to less than 1 min. The good stability and fast response achieved by using this technology make it suitable for the medical use of iBNCT accelerators. This technology will be extremely useful in the development of similar accelerators. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
38. Ultracompact Compton camera for innovative gamma-ray imaging.
- Author
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Kataoka, J., Kishimoto, A., Taya, T., Mochizuki, S., Tagawa, L., Koide, A., Sueoka, K., Morita, H., Maruhashi, T., Fujieda, K., Kurihara, T., Arimoto, M., Okochi, H., Katsumi, N., Kinno, S., Matsunaga, K., Ikeda, H., Shimosegawa, E., Hatazawa, J., and Ohsuka, S.
- Subjects
- *
GAMMA rays , *PHOTON counting , *SCINTILLATORS , *NUCLEAR counters - Abstract
Abstract A multipixel photon counter (MPPC) features excellent photon-counting capability as a radiation detector. In particular, a two-plane Compton camera consisting of Ce:GAGG scintillators coupled with MPPC arrays has significant application potential owing to its compact size and low weight. For example, the camera can be easily mounted on a commercial drone to identify radiation hot spots from the sky. In Fukushima, we demonstrated that a 137Cs distribution within a 100 m diameter can be mapped correctly within a couple of tens of minutes. The advanced use of the Compton camera is also anticipated in the field of proton therapy. We evaluated an image of 511 keV annihilation gamma-rays emitted from a PMMA phantom irradiated by 200 MeV protons to mimic an in-beam monitor for proton therapy. Finally, we developed an ultracompact Compton camera (weight = 580 g), for 3-D multicolor molecular imaging. In order to demonstrate the performance capabilities of the device, 131I (365 keV) , 85SrCl 2 (514 keV), and 65ZnCl 2 (1116 keV) were injected into a living mouse and the data were taken from 12 angles with a total acquisition time of 2 h. We confirmed that all tracers had accumulated on the target organs of the thyroid, bone, and liver, and that the obtained 3-D image was quantitatively correct with an accuracy of ± 20%. Highlights • First demonstration of a Compton camera onboard a drone for aerial snapshots in Fukushima. • Application of a Compton camera for prompt gamma-ray imaging during proton therapy. • 3-D multicolor imaging of a living mouse by using an ultracompact Compton camera whose weight is only 580 g. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
39. Investigation of the neutron spectrum measurement method for dose evaluation in boron neutron capture therapy.
- Author
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Onishi, T., Kumada, H., Takada, K., Sakae, T., Naito, F., and Kurihara, T.
- Subjects
- *
BORON-neutron capture therapy , *SCINTILLATION spectrometer , *NEUTRON spectrometers , *RADIOACTIVITY , *TUMOR diagnosis - Abstract
In boron neutron capture therapy, it is important to evaluate the dose administered to a patient's body outside the tumour area. The exposure dose is evaluated by calculation; however, the calculated value must be validated using a measured value. The dose evaluations based on the measured neutron spectrum are investigated. Multi-foil activation, combined with a LiCaAlF 6 scintillation detector and an imaging plate, is proposed as a measurement method. The proposed method can measure the neutron spectrum at various points quickly. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
40. What is the Risk Factor of Graft Mortality in Patients who Underwent Simultaneous Splenectomy during Living Donor Liver Transplantation?
- Author
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Yoshizumi, T., Harada, N., Toshima, T., Takeishi, K., Morita, K., Nagao, Y., Kurihara, T., Tomino, T., Kosai-Fujimoto, Y., and Itoh, S.
- Subjects
- *
LIVER transplantation , *SPLENECTOMY ,MORTALITY risk factors - Published
- 2022
- Full Text
- View/download PDF
41. Prognostic Impact of Des-γ-carboxyl Prothrombin in Living-Donor Liver Transplantation for Recurrent Hepatocellular Carcinoma.
- Author
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Harimoto, N., Yoshida, Y., Kurihara, T., Takeishi, K., Itoh, S., Harada, N., Tsujita, E., Yamashita, Y.-I., Uchiyama, H., Soejima, Y., Ikegami, T., Yoshizumi, T., Kawanaka, H., Ikeda, T., Shirabe, K., Saeki, H., Oki, E., Kimura, Y., and Maehara, Y.
- Subjects
- *
LIVER cancer , *PROTHROMBIN , *ORGAN donors , *LIVER transplantation , *LIVER cancer patients , *DISEASE relapse , *HEALTH outcome assessment , *PROGNOSIS - Abstract
Background Although the Milan criteria are widely accepted for liver transplantation (LT) in patients for hepatocellular carcinoma (HCC), they have not been fully evaluated for salvage LT in patients with recurrent HCC. We have previously reported outcomes of living-donor LT (LDLT) for HCC and identified 2 risk factors affecting recurrence-free survival (RFS): tumor size >5 cm and des-γ-carboxyl prothrombin (DCP) concentration >300 mAU/mL (Kyushu University criteria). This study was designed to clarify risk factors for tumor recurrence after LDLT in patients with recurrent HCC. Methods Outcomes in 114 patients who underwent LDLT for recurrent HCC were analyzed retrospectively. RFS rates after LDLT were calculated, and risk factors for tumor recurrence were identified. Results The 1-, 3-, and 5-year RFS rates after LDLT were 90.6%, 80.4%, and 78.8%, respectively. Univariate analysis showed that tumor recurrence was associated with alpha-fetoprotein concentration ≥300 ng/mL, DCP concentration ≥300 mAU/mL, tumor number ≥4, tumor size ≥5 cm, transarterial chemotherapy before LDLT, duration of last treatment of HCC to LDLT <3 months, bilobar distribution, exceeding Milan criteria, exceeding Kyushu University criteria, poor differentiation, and histologic vascular invasion. Multivariate analysis showed that DCP ≥300 mAU/mL ( P = .03) and duration from last treatment to LDLT <3 months ( P = .01) were independent predictors of RFS. Conclusions DCP concentration and time between last treatment and LDLT are prognostic of RFS in patients undergoing LDLT for HCC. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
42. High-precision compton imaging of 4.4 MeV prompt gamma-ray toward an on-line monitor for proton therapy.
- Author
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Mochizuki, S., Kataoka, J., Koide, A., Fujieda, K., Maruhashi, T., Kurihara, T., Sueoka, K., Tagawa, L., Yoneyama, M., and Inaniwa, T.
- Subjects
- *
COMPTON imaging , *PROTON therapy , *PROTON beams , *GAMMA rays , *PHOTON detectors , *SCINTILLATORS , *POSITRONS - Abstract
Proton therapy is a widely used and effective treatment for cancer. A high-dose concentration of proton beam reduces damage to normal tissues. However, it also requires a high accuracy of irradiation. PET is generally used to verify the proton range after irradiation, but, the distributions of positrons and the energy deposited by protons are not similar to each other. Recently, prompt gamma-ray imaging has attracted attention as a new, online imaging technique. In particular, 4.4 MeV gamma rays emitted from 12C* is one of the best probes to monitor the proton dose, however imaging techniques are far from established. We have developed a novel, 3-D position sensitive Compton camera based on Ce:GAGG scintillators coupled with multi-pixel photon counter (MPPC) arrays, thus making it optimized for imaging in the 1–10 MeV range. The angular resolution is 5 degrees (FWHM) at 4.4 MeV. We have established various methods to discriminate multiple-Compton and escape events, both of which can be critical backgrounds for precise imaging of prompt gamma rays. By irradiating a 70 MeV proton beam on the PMMA phantom, we demonstrated that 4.4 MeV gamma ray image is sharply concentrated on the Bragg peak, as was expected from the PHITS simulation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
43. Development of novel neutron camera to estimate secondary particle dose for safe proton therapy.
- Author
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Tagawa, L., Kataoka, J., Sueoka, K., Fujieda, K., Kurihara, T., Arimoto, M., Mochizuki, S., Maruhashi, T., Toshito, T., Kimura, M., and Inaniwa, T.
- Subjects
- *
PROTON therapy , *FAST neutrons , *NEUTRONS , *NEUTRON sources , *NEUTRON irradiation , *CAMERAS - Abstract
Proton therapy causes less damage to healthy tissue compared to other radiation therapies; however, the possible damage caused by secondary, fast neutrons is almost unknown. In some simulations, neutron dose amounts to 10% of the proton dose; therefore, a real-time visualization of the neutron dose is needed. We have developed a neutron camera that can visualize the direction and intensity of fast neutron sources. The camera consists of eight units of a plastic scintillator (EJ-299-34) coupled with a compact PMT (R9880U). We demonstrate that a 252Cf neutron source is correctly imaged with an angular resolution of 15.5 deg (FWHM). In addition, fast neutrons emitted from the brass block irradiated by 70 MeV were successfully monitored in real time. Finally, we present our prospects for future clinical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
44. Associations of time to return to performance following acute posterior thigh injuries with running biomechanics, hamstring function, and structure in collegiate sprinters: A prospective cohort design.
- Author
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Otsuka, M., Isaka, T., Terada, M., Arimitsu, T., Kurihara, T., and Shinohara, Y.
- Subjects
- *
HAMSTRING muscle physiology , *KNEE physiology , *SPORTS participation , *ISOMETRIC exercise , *RANGE of motion of joints , *THIGH , *RUNNING injuries , *EXERCISE physiology , *MAGNETIC resonance imaging , *COMPARATIVE studies , *HAMSTRING muscle , *BIOMECHANICS , *SPRINTING , *LONGITUDINAL method - Abstract
The time to return to sport from acute hamstring strain injuries is associated with several functional and structural impairments. However, not all previous studies assessed the preinjury level before acute hamstring strain injuries directly. The purpose of this study was to examine the associations of the time to return to performance following acute hamstring strain injuries with deficits in running biomechanics, hamstring function and structure in collegiate sprinters by a prospective study. Using a prospective cohort design, 72 participants were recruited from a collegiate track and field team. At the preinjury assessment, a 60-m running-specific test, passive straight leg raise test and isometric knee flexion strength test were assessed at the beginning of the competitive season for three consecutive years (2017–2019). Afterwards, postinjury examinations were performed only in sprinters with acute hamstring strain injuries. Twelve sprinters strained their hamstring muscle (incidence rate of hamstring strain injuries: 16.7%); the majority (n = 10) were classified as grades 0–2. The running speed deficit of the running-specific test was associated with the time to return to performance as well as the passive straight leg raise test deficit. In the running-specific test, lower-limb kinetic deficits were more strongly associated with the time to return to performance compared to lower-limb kinematic deficits. A running-specific test may be considered one of the most convenient and valid tests for assessing rehabilitation progress after acute hamstring strain injuries. • Incidence rate of hamstring strain injuries was 16.7% during competition season. • Majority (83.3%) of injuries was grades 0–2 and the other (16.7%) was grade 3. • Running speed and kinetic deficits relate to time to return to performance. • Altered hamstring strength and flexibility relate to rehabilitation process. • Magnetic resonance image measures may not be related to rehabilitation process. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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45. Asynchronous all-optical bit-by-bit self-signal recognition and demultiplexing from overlapped signals achieved by self-frequency shift of Raman soliton.
- Author
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Kato, M., Fujiura, K., and Kurihara, T.
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PACKET switching , *ASYNCHRONOUS circuits , *DIGITAL electronics , *SOLITONS , *PHOTONICS , *MULTIPLEXING - Abstract
Asynchronous all-optical bit-by-bit self-signal recognition and simultaneous demultiplexing based on intensity-dependent self-frequency shift induced by Raman soliton effect is demonstrated. Better than 3 dB recognition sensitivity, faster than 640 Gbit/s demultiplexing and capability of three-times cascade operation are confirmed. [ABSTRACT FROM AUTHOR]
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- 2004
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46. Prognostic Impact of Vessels that Encapsulate Tumor Cluster (VETC) in Patients who Underwent Liver Transplantation for Hepatocellular Carcinoma.
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Toshima, T., Yoshizumi, T., Harada, N., Morita, K., Nagao, Y., Kurihara, T., Tomino, T., Kosai-Fujimoto, Y., Tomiyama, T., Morinaga, A., Toshida, K., and Itoh, S.
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LIVER transplantation , *TUMORS - Published
- 2022
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47. High Expression of Leucine-Rich Repeat Neuronal 2 Is the Graft Quality Marker in Living Donor Liver Transplantation.
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Tomiyama, T., Yoshizumu, T., Itoh, S., Morita, K., Toshima, T., Takeishi, K., Nagao, Y., Kurihara, T., Tomino, T., Kosai-Fujimoto, Y., and Harada, N.
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LIVER transplantation - Published
- 2022
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48. The association between neutropenia and prognosis in stage III colorectal cancer patients receiving adjuvant chemotherapy.
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Sunaga, T., Suzuki, S., Kogo, M., Kurihara, T., Kaji, S., Koike, N., Harada, N., Suzuki, M., and Kiuchi, Y.
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ACADEMIC medical centers , *COLON tumors , *COMBINED modality therapy , *MEDICAL records , *MULTIVARIATE analysis , *NEUTROPENIA , *HEALTH outcome assessment , *T-test (Statistics) , *TREATMENT effectiveness , *PROPORTIONAL hazards models , *RETROSPECTIVE studies , *DATA analysis software , *DESCRIPTIVE statistics , *KAPLAN-Meier estimator , *PROGNOSIS ,RECTUM tumors - Abstract
Neutropenia during chemotherapy has been reported to be a predictor of better survival in patients with several types of cancer, although there are no reports on stage III colorectal cancer ( CRC). The purpose of this study was to examine the association between neutropenia and prognosis in stage III CRC patients receiving adjuvant chemotherapy consisting of oral uracil and tegafur ( UFT) plus leucovorin ( LV). We retrospectively analysed 123 patients with stage III CRC who received UFT/ LV as adjuvant chemotherapy. The end-point was disease-free survival ( DFS). Survival curves of the two categories (neutropenia absent vs. present) were estimated using the Kaplan- Meier method and compared by the log-rank test. We estimated the hazard ratio ( HR) for DFS according to neutropenia after adjustment for covariates by multivariate analyses using Cox's regression analysis. A total of 33 (26.8%) patients experienced neutropenia. Patients without neutropenia showed a significantly lower DFS than those with neutropenia (3-year DFS 57.3% vs. 81.2%, P = 0.0213). By multivariate analysis, neutropenia and histological type were independent prognostic factors, with HR of 0.410 (neutropenia absent vs. present, P = 0.045) and 4.793 (well to moderately differentiated vs. poorly differentiated, P = 0.004) respectively. We demonstrated that neutropenia occurring during adjuvant chemotherapy consisting of UFT/ LV may be a prognostic factor of recurrence in stage III CRC patients. [ABSTRACT FROM AUTHOR]
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- 2014
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49. Development of a transmission positron microscope
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Matsuya, M., Jinno, S., Ootsuka, T., Inoue, M., Kurihara, T., Doyama, M., and Fujinami, M.
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TRANSMISSION electron microscopes , *POSITRONS , *ELECTRON beams , *MONTE Carlo method , *OPTICS , *SCATTERING (Physics) , *DIFFRACTION patterns - Abstract
Abstract: A practical transmission positron microscope (TPM) JEM-1011B has been developed to survey differences in the interaction of positron and electron beams with materials, and is installed in the Slow Positron Facility of High Energy Accelerator Research Organization (KEK). The TPM can share positron and electron beams, and can also be used as a transmission electron microscope (TEM). Positron transmission images up to magnification 10,000× (resolution: 50nm) and positron diffraction patterns up to 044 family were successfully obtained by the TPM comparing them with those of electrons. The differences in material transmittances for both beams have been measured, and can be explained by the calculated results of the Monte Carlo simulation code PENELOPE-2008. [Copyright &y& Elsevier]
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- 2011
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50. Quantification of hepatitis C virus in patients treated with peginterferon-alfa 2a plus ribavirin treatment by COBAS TaqMan HCV test.
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Kanda, T., Imazeki, F., Yonemitsu, Y., Mikami, S., Takada, N., Nishino, T., Takashi, M., Tsubota, A., Kato, K., Sugiura, N., Tawada, A., Wu, S., Tanaka, T., Nakamoto, S., Mikata, R., Tada, M., Chiba, T., Kurihara, T., Arai, M., and Fujiwara, K.
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VIRAL hepatitis , *INTERFERONS , *RIBAVIRIN , *HEPATITIS C virus , *TERMINATION of treatment , *COMBINATION drug therapy , *PREDICTION models , *THERAPEUTICS - Abstract
Extremely low levels of serum hepatitis C virus (HCV) RNA can be detected by COBAS TaqMan HCV test. To investigate whether the COBAS TaqMan HCV test is useful for measuring rapid virological response (RVR) and early virological response (EVR) to predict sustained virological response (SVR), we compared the virological response to PEG-IFN-alfa 2a plus RBV in 76 patients infected with HCV genotype 1 when undetectable HCV RNA by the COBAS TaqMan HCV test was used, with those when below 1.7 log IU/mL HCV RNA by COBAS TaqMan HCV test was used, which corresponded to the use of traditional methods. Among the 76 patients, 28 (36.8%) had SVR, 13 (17.1%) relapsed, 19 (25.0%) did not respond, and 16 (21.0%) discontinued the treatment due to side effects. The positive predictive values for SVR based on undetectable HCV RNA by COBAS TaqMan HCV test at 24 weeks after the end of treatment [10/10 (100%) at week 4, 21/23 (91.3%) at week 8 and 26/33 (78.7%) at week 12] were superior to those based on <1.7 log IU/mL HCV RNA [17/19 (89.4%) at week 4, 27/38 (71.0%) at week 8, and 27/43 (62.7%) at week 12]. The negative predictive values for SVR based on <1.7 log IU/mL HCV RNA by COBAS TaqMan HCV test [46/57 (80.7%) at week 4, 37/38 (97.3%) at week 8, and 32/33 (96.9%) at week 12] were superior to those based on undetectable HCV RNA [48/66 (72.7%) at week 4, 46/53 (86.7%) at week 8, and 41/43 (95.3%) at week 12]. The utilization of both undetectable RNA and <1.7 log IU/mL HCV RNA by COBAS TaqMan HCV test is useful and could predict SVR and non-SVR patients with greater accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
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