• Title/Summary/Keyword: Nagasaki

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Comparison of proliferation resistance among natural uranium, thorium-uranium, and thorium-plutonium fuels used in CANada Deuterium Uranium in deep geological repository by combining multiattribute utility analysis with transport model

  • Nagasaki, Shinya;Wang, Xiaopan;Buijs, Adriaan
    • Nuclear Engineering and Technology
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    • v.50 no.5
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    • pp.794-800
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    • 2018
  • The proliferation resistance (PR) of Th/U and Th/Pu fuels used in CANada Deuterium Uranium for the deep geological repository was assessed by combining the multiattribute utility analysis proposed by Chirayath et al., 2015 with the transport model of radionuclides in the repository and comparing with that of the used natural U fuel case. It was found that there was no significant advantage for Th/U and Th/Pu fuels from the viewpoint of the PR in the repository. It was also found that the PR values for used nuclear fuels in the repository of Th/U, Th/Pu, and natural U was comparable with those for enrichment and reprocessing facilities in the pressurized water reactor (PWR) nuclear fuel cycle. On the other hand, the PR values considering the transport of radionuclides in the repository were found to be slightly smaller than those without their transport after the used nuclear fuels started dissolving after 1,000 years.

Genetic factors associated with development of cerebral malaria and fibrotic schistosomiasis

  • Hirayama, Kenji
    • Parasites, Hosts and Diseases
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    • v.40 no.4
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    • pp.165-172
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    • 2002
  • Collaborative studies have identified some genetic factors contributing to the development of severe forms of malaria and schistosomiasis. In Thailand, the $TNF-{\alpha}{\;}5'-flanking$ region shows biallelic polymorphic sites at nucleotides -238, -308, -857, -863, and -1031, and seven alleles have been identified in patients from Myanmar. We found that the TNF promoter (TNFP)-D allele was significantly associated with cerebral malaria in populations from Karen (P < 0.0001. OR = 124.86) and ethnic Burma (P < 0.0001, OR = 34.50) . In China, we have identified two major genes related to the severity of liver fibrosis, one an HLA class II gene, and the other the IL-13 gene. The frequency of the HLA- DRB5*0101 allele and that of the IL-13 promoter A/A (IL- l3P- A/A) genotype were elevated in fibrotic patients, although the two genes are located on different chromosomes, chromosomes 6p and 5q, respectively Subjects with both genotypes had odds ratios (OR = 24.5) much higher than the sum of the ratios for each individual genotype (OR = 5.1,95% Confidence Interval 1.3-24.7 for HLA-DRB5*0101, OR = 3.1 95% CI 1.5 - 6.5 for IL-l3P-A/A). That the effects of the two susceptibility markers are synergistic rather than additive, strongly suggests that the pathogenic Th2 response directly influences the prognosis of post-schistosomal liver fibrosis.

The Channel Wall Confinement Effect on Periodic Cryogenic Cavitation from the Plano-convex Foil

  • Ito, Yutaka;Nagayama, Tsukasa;Yamauchi, Hiroshi;Nagasaki, Takao
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.03a
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    • pp.383-390
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    • 2008
  • Flow pattern of cavitation around a plano-convex foil, whose shape is similar to the inducer impeller of the turbo-pumps in the liquid fuel rocket engine, was observed by using a cryogenic cavitation tunnel of blowdown type for visualization. Working fluids were liquid nitrogen and hot water. The parameter range to be varied was between 20 and 60mm for channel width, 20 and 60mm for foil chord, -1.8 and 13.2 for cavitation number, 3.7 and 19.5m/sec for averaged inlet velocity, $8.5{\times}10^4$ and $1.5{\times}10^6$ for Reynolds number, -8 and $8^{\circ}$ for angle of attack, respectively. Especially at positive angle of attack, namely, convex surface being downstream, the whole cavity or a part of the cavity on the foil surface departs periodically. Periodic cavitation occurs only in case of smaller cavitation size than twice foil chord. Cavitation thickness and length in 20mm wide channel are larger than those in 60mm due to the wall confinement effect. Therefore, periodic cavitation in 60mm wide channel easily occurs than that in 20mm. These results suggest that the periodic cavitation is controlled by not only the hydrodynamic effect of vortex shedding but also the channel wall confinement effect.

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New Bubble Size Distribution Model for Cryogenic High-speed Cavitating Flow

  • Ito, Yutaka;Tomitaka, Kazuhiro;Nagasaki, Takao
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.03a
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    • pp.700-710
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    • 2008
  • A Bubble size distribution model has been developed for the numerical simulation of cryogenic high-speed cavitating flow of the turbo-pumps in the liquid fuel rocket engine. The new model is based on the previous one proposed by the authors, in which the bubble number density was solved as a function of bubble size at each grid point of the calculation domain by means of Eulerian framework with respect to the bubble size coordinate. In the previous model, the growth/decay of bubbles due to pressure difference between bubble and liquid was solved exactly based on Rayleigh-Plesset equation. However, the unsteady heat transfer between liquid and bubble, which controls the evaporation/condensation rate, was approximated by a theoretical solution of unsteady heat conduction under a constant temperature difference. In the present study, the unsteady temperature field in the liquid around a bubble is also solved exactly in order to establish an accurate and efficient numerical simulation code for cavitating flows. The growth/decay of a single bubble and growth of bubbles with nucleation were successfully simulated by the proposed model.

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Fukuoka Next-generation Social System Creation Hub as a Regional Innovation Platform Strategy

  • Cha, Sang-Ryong
    • World Technopolis Review
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    • v.7 no.2
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    • pp.125-134
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    • 2018
  • The purpose of this article is to introduce and describe the case of Fukuoka Next-generation Social System Creation Hub based on the conceptual framework of regional innovation platform strategy. In short, it is a "government-issued" regional innovation platform strategy to improve innovativeness with limited creative capital through "borrowing" not money but network, wisdom, know-how, and ideas from each other between some stakeholder groups in a region. The Fukuoka Industry, Science & Technology Foundation, which is the coordinating institution of the whole program, plays the role of a platformer to unify various projects into the program crossing borders between stakeholder groups for building regional innovation platforms that lends intensive support to feedback loops between the program facilitator and its partners in the program. Thanks to being a government-issued one, it could be tied together with some wide ranging issues of policy on social innovations, such as the "low carbon society" or the "health and longevity society." But at the same time, it is a concern that many regional research institutions that have innovative potential and diverse ideas become governed by the platform without their noticing it and dealt with in the same way based on "selected" and "designated" strategic goals. Therefore, it seems that a regional innovation platform strategy is a kind of "double-edged sword" in public policy in the era of "panopticism of bureaucratic society" in Japan.

Sorption of Np(IV) on MX-80 in Ca-Na-Cl Type Reference Water of Crystalline Rock

  • Nagasaki, Shinya
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.19 no.1
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    • pp.1-7
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    • 2021
  • The pH dependence of sorption distribution coefficient (Kd) of Np(IV) on MX-80 in Ca-Na-Cl type solution with the ionic strength of 0.3 M, which was similar to one of the reference groundwaters in crystalline rock, was experimentally investigated under the reducing conditions. The overall trend of Kd on MX-80 was independent of pH at 5 ≤ pH ≤ 10 but increased as pH increased at pH ≤ 5. The 2-site protolysis non-electrostatic surface complexation and cation exchange model was applied to the experimentally measured pH dependence of Kd and the optimized surface complexation constants of Np(IV) sorption on MX-80 were estimated. The values of surface complexation constants in this work agreed relatively well with those in the Na-Ca-Cl solution previously evaluated, suggesting that compared to Na+, the competition of Ca2+ with Np(IV) for surface complexation on MX-80 was not much strong in Ca-Na-Cl solution. The sorption model well predicted the pH dependence of Kd values but slightly overestimated the sorption at the low pH region.

Sorption of Se(-II) on illite, MX-80 bentonite, shale, and limestone in Na-Ca-Cl solutions

  • Walker, Andrew;Racette, Joshua;Saito, Takumi;Yang, Tammy (Tianxiao);Nagasaki, Shinya
    • Nuclear Engineering and Technology
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    • v.54 no.5
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    • pp.1616-1622
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    • 2022
  • Selenium has been identified as an element of interest for the safety assessment of a deep geological repository (DGR) for used nuclear fuel. In Canada, groundwaters at DGR depths in sedimentary rocks have been observed to have a high ionic strength. This paper examines the sorption behavior of Se(-II) onto illite, MX-80 bentonite, Queenston shale, and argillaceous limestone in Na-Ca-Cl solutions of varying ionic strength (0.1-6 mol/kgw (m)) and across a pH range of 4-9. Little ionic strength dependence for Se(-II) sorption onto all solids was observed except that sorption at high ionic strength (6 m) was generally slightly lower than sorption at low ionic strength (0.1 m). Illite and MX-80 exhibited the expected results for anion sorption, while shale and limestone exhibited more constant sorption across the pH range tested. A non-electrostatic surface complexation model successfully predicted sorption of Se(-II) onto illite and MX-80 using the formation of an inner-sphere surface complex and an outer-sphere surface complex. Optimized values for the formation reactions of these surface species were proposed.

Quantitative determination of 2'-Hydroxy-3',4'-methylenedioxy-3,4,5-trimethoxychalcone (HMTC) in rat plasma by HPLC-MS/MS and its application to a pharmacokinetic study

  • Jihyun Won;Juhyung Kang;Wonyoung Park;Jose C. J. M. D. S. Menezes;Marc Diederich;Eunyoung Kim;Wonku Kang
    • Analytical Science and Technology
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    • v.36 no.1
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    • pp.53-58
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    • 2023
  • 2'-Hydroxy-3',4'-methylenedioxy-3,4,5-trimethoxychalcone (HMTC) is a newly synthesized chalcone that affects proliferation, cytotoxic potential and apoptosis in human leukemia cells. However, no validated determination method has been described so far for HMTC in biological samples. Thus, we developed a liquid chromatographic method using a tandem mass spectrometry to determine HMTC in rat plasma. Liquid-liquid extraction with ethyl acetate was used for the clean-up procedure. The analyte was separated on a reversedphase column with mobile phase of distilled water and acetonitrile (2:8, v/v, including 0.1 % formic acid). The ion transition of the precursor to the product ion was principally deprotonated ions [M-H]- at m/z 356.8 → 327.2 for HMTC. This analytical method was successfully applied in pharmacokinetic study of HMTC after intravenous administration in rats.

UV-responsive intracellular signaling pathways: MAPK, p53, and their crosstalk

  • Matsuda, Naoki
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.229-232
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    • 2002
  • There are two distinct UV-responsive signaling pathways in UV-irradiated mammalian cells, i.e., the DNA damage-dependent and -independent pathways. The former occurs in nucleus and results in growth arrest and apoptosis via post-translational modification of p53. The latter is initiated by oxidative stress and/or by damages in cell membrane or cytoplasm, which activate signaling cascade through intracellular molecules including mitogen activated protein kinases (MAPK). In normal human fibroblastic cells, all of MAPK family members, extracellular signal-related kinases (ERK), c-Jun N-terminal kinases (JNK) and p38, were rapidly phosphorylated following UV-irradiation. ERK phosphorylation was suppressed by an inhibitor of receptor tyrosine kinases (RTK). As ERK usually responds to mitogenic stimuli from RTK ligands, UV-induced ERK phosphorylation may be linked to the proliferation of survived cells. In contrast, phosphorylation of JNK and p38, as well as apoptosis, were modulated by the level of UV-generated oxidative stress Therefore, JNK and p38 may take part in oxidative stress-mediated apoptosis. Phosphorylation of p53 at Ser and Thr residues are essential for stabilization and activation of p53. Among several sites reported, we confirmed phosphorylation at Ser-15 and Ser-392 after UV-irradiation. Both of these were inhibited by a phosphoinositide 3-kinase inhibitor, presumably due to the shutdown of signals from DNA damage to p53. Phosphorylation at Ser-392 was also sensitive to an antioxidant and a p38 inhibitor, suggesting that Ser-392 of p53 is one of the possible points where DNA damage-dependent and -independent apoptic signals merge. Thus, MAPK pathway links UV-induced intracellular signals to the nuclear responses and modifies DNA damage-dependent cellular outcome, resulting in the determination of cell death.

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Reproduction of the Goby Fish Periophthalmus magnuspinnatus in Mud Flat of Suncheon Bay, Korea (한국 순천만 갯벌지역 큰볏말뚝망둥어(Periophthalmus magnuspinnatus)의 생식)

  • Kim, Jae-Won;Yoon, Yang-Ho;Shin, Hyun-Chool;Takita, Toru;Kim, Ji-Hyung;Park, Se-Chang;Park, Chan-Il;Baeck, Gun-Wook
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.4
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    • pp.289-293
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    • 2008
  • Reproduction of the goby fish Periophthalmus magnuspinnatus was examined using 298 specimens collected from April to October 2005 in a mud flat of Suncheon Bay, Korea. Specimens ranged in body length(BL) from 1.3 to 9.1 cm. The gonadosomatic index(GSI) of females was highest in June and decreased until August. The hepatosomatic index(HSI) and fatness index of females were high in April and then decreased to nadirs in July. Spawning season lated from April to August and the ratio of females to males did not significantly differ($x^2$-test, p>0.05). The first spawning length was 4.5 cm BL, and the size of 50% maturity was estimated at 4.98 cm BL. Fecundity(F) ranged from 1,316 to 4,768 eggs, and the relationship between F and BL was estimated as $F=0.1562BL^{1.4068}(R^2=0.59)$.