• Journal of Energy Engineering
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• v.13 no.4
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• pp.242-258
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• 2004

The duplex burnable poison absorbers concept was suggested by Korea Atomic Energy Research Institute. This BP rod is composed of inner region of natural U-Gd$_2$O$_3$ and outer shell of enriched UO$_2$-Er$_2$O$_3$. It is expected that this burnable absorber has same reactivity control capability with gadolinia burnable absorber used in extened fuel cycle. In order to evaluate the nuclear feasibility of duplex BPs, the nuclear design characteristics were compared with that of four types of burnable absorbers; gadolinia, erbia, IFBA, dysprosia duplex BP on 24 months fuel cycle for Korean Standard Nuclear Power plants. According to the evaluation results of nuclear characteristics, the duplex BPs were better than other BPs on k-infinitives, reactivity holddown worth (RHW), pin power peaking and moderator temperature coefficient (MTC). The possibility of nuclear core design was also confirmed based on the optimized fuel assemblies which were searched for a sensitivity analysis. Characteristics of core design with duplex BPs was compared with that of reference core with gadolinia BPs for cycle length, power peaking and MTC. The duplex BP core had a little longer cycle length by 4 to 7 days because of increased amount of fissile in enriched uranium at the outer shell of duplex BP In case of power peaking F$\_$Q/ of duplex BP core was reduced from 1.5773 to 1.5335. MTC was also less -0.48 pcm/C than that of reference core. Finally, evaluation of fuel cycle economy was performed for the manufacturing feasibility test and fuel cost evaluation with duplex BPs. Fuel cycle economy of duplex BP core almost was equivalent with that of gadolinia BP core.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.769-777
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• 2004

A Helicobacter pylori urease inhibitor from Rubus coreanus Miquel has been isolated and partially characterized for aiming to Prevent H. pylori growth and decrease harmful accumulation of ammonia in human gastric mucosa. We screened urease inhibitory activities in 519 extracts library prepared by solvent extraction from 173 kinds of edible plants, medicinal herbs, herbs and seaweeds using a colorimetric urease assay system. As results of primary and secondary screening, 70% acetone extract of Rubus coreanus Miquel was selected as potent candidate, showing about 24% inhibitory activity. The acetone extract was sequentially partitioned into RCE/RCWI and RCB/RCW2 layers with ethyl acetate and butanol. The major active component in RCW2, water layer from butanol fractionation was revealed to be peptidic or proteinous substance by inhibitory activity determination after pronase digestion and periodate oxidation. RCW2-IIIc a was isolated by sequential column chromatography on DEAE-Toyopearl 650C, Butrl-Toyopearl 650M and Sephadex LH-20. The isolated urease inhibitor RCW2-IIIc $\alpha$, was highly pure proteinous substance with molecular weight of 13kDa by high-performance gel permeation liquid chromatography. RCW2-IIIc$\alpha$ has about 5 times higher inhibitory activity than 70％ acetone extract, showing high stability against heat treatment and peptic digestion.

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.277-284
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• 2018

In this study, we investigated the anti-allergic effect of the ethyl acetate fraction of Ecklonia cava (EC-EtoAc) on the immunoglobulin E (IgE)/bovine serum albumin (BSA)-mediated activation of bone marrow-derived cultured mast cells (BMCMCs). We revealed that the $62.5{\mu}g/ml$ of EC-fractions ($EC-CHCl_3$, EC-Hexane and EC-EtoAc) inhibited IgE/BSA-activated ${\beta}$-hexosaminidase release from BMCMCs without cytotoxicity. Especially, EC-EtoAc showed the higher ${\beta}$-hexosaminidase release than the others. Also, EC-EtoAc reduced the expression levels of cytokines such as interleukin (IL)-$1{\beta}$, IL-4, IL-5, IL-6, IL-10, IL-13, interferon (IFN)-${\gamma}$ and tumor necrosis factor (TNF)-${\alpha}$ and a chemokine, thymus- and activation-regulated chemokine (TARC), compared to the only IgE/BSA-treated BMCMCs. Furthermore, EC-EtoAc significantly prevented the binding of IgE to Fc epsilon receptor $(Fc{\varepsilon}R)I$ and reduced the $Fc{\varepsilon}RI$ expression on the sensitized BMCMCs. Taken together, these results suggest that E. cava may be the natural agent with beneficial potentials for the treatment of type I allergic diseases induced by mast cell activation.

• Journal of the Korea Society of Computer and Information
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• v.25 no.6
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• pp.165-170
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• 2020

In this paper, it was confirmed that scopoletin inhibits neuroinflammation induced by amyloid beta oligomer (Aβ_1-42) in microglial BV-2. The mechanisms of inflammatory cytokines and inflammatory mediators by scopoletin were identified. Alzheimer's disease is the most common neurodegenerative disease, but it is a disease whose specific etiology is unknown, and many studies are trying to solve it. We first measured the cell viability with the CCK-8 assay method to confirm that scopoletin and Aβ_1-42 are toxic to BV-2 cells. Expression levels of interleukin 1 beta (IL-1β), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and nuclear factor-κB (NF-κB) in inflammatory reactions induced by Aβ_1-42 with western blot were analyzed. The ANOVA assay was used to compare protein expression differences between BV-2 cells treated with Aβ_1-42 alone and BV-2 cells pretreated with Aβ_1-42 and scopoletin. Therefore, this study suggested that scopoletin is worth developing as a neuroinflammatory protection agent for Alzheimer's disease in the future.

• Food Science and Preservation
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• v.25 no.1
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• pp.27-35
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• 2018

In this study, we evaluated the antioxidant activity and anti-inflammatory effects of Abeliophyllum distichum (A. distichum) leaves that were prepared via air-drying. Fresh and air-dried A. distichum leaves were examined via 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assay and measurements of the reducing power. The suppression effects on inflammation of the leaves were analyzed by a western blot and RT-PCR on LPS-induced RAW 264.7 cells. As a result, the antioxidant activity of the fresh leaves was found to be more effective than that of the air-dried leaves. Also, the fresh leaves were more effective in suppressing the protein and mRNA levels of iNOS and COX-2 than the air-dried leaves, thereby indicating the better anti-inflammatory effects. In addition, the contents of phenolic compounds and acteoside were analyzed by high-performance liquid chromatography (HPLC). The results showed that the acteoside content decreased with the use of the air-drying method, while there was no change in the content of phenolic compounds. Therefore, this study indicated that fresh A. distichum leaves potential antioxidant and suppression activities of various factors that are involved in the production of NO, which were found to be better than those of air-dried A. distichum leaves. These biological activities were also found to be independent of the content of phonolic compounds and were assumed to be directly or indirectly related to the content of acteoside.

• Composites Research
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• v.34 no.5
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• pp.290-295
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• 2021

The application of lightweight structural composites to automobiles as a solution in line with global fuel economy regulations to curb global warming is recognized as a megatrend. This study was conducted to provide a technical approach that can respond to the issue of replacing parts that require conductive properties to maximize the application of thermoplastic carbon fiber reinforced plastics (CFRPs), which are advantageous in terms of repair, disposal and recycling. By utilizing the properties of the low-viscosity polymerizable oligomer matrix, it was possible to prepare a thermoplastic CFRP exhibiting excellent impregnation properties while uniformly mixing the conductive filler. Various carbon-based conductive fillers such as carbon black, carbon nanotubes, graphene nanoplatelets, graphite, and pitch-based carbon fibers were filled up to the maximum content, and electrical and thermal conductive properties of the fabricated composites were compared and studied. It was confirmed that the maximum incorporation of filler was the most important factor to control the conductive properties of the composites rather than the type or shape of the conductive carbon filler. Experimental results were observed in which it might be advantageous to apply a one-dimensional conductive carbon filler to improve electrical conductivity, whereas it might be advantageous to apply a two-dimensional conductive carbon filler to improve thermal conductivity. The results of this study can provide potential insight into the optimization of structural design for controlling the conductive properties of thermoplastic CFRPs.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.403-412
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• 2021

This study aimed to identify plant growth-promoting activity, phytopathogenic fungi growth inhibitory activity, mineral solubilization ability, and extracellular enzyme activity of the genus Bacillus in soil and the rhizosphere. With regards to antifungal activity against phytopathogenic fungi, DDP257 showed antifungal activity against all 10 pathogenic fungi tested. ANG20 showed the highest ability to produce indole-3-acetic acid, a plant growth-promoting factor (70.97 ㎍/ml). In addition, 10 species were identified to have 1-aminocyclopropane-1-carboxylate deaminase production ability, and most isolates showed nitrogen fixation and siderophore production abilities. Thereafter, the isolated strains' ability to solubilize minerals such as phosphate, calcite, and zinc was identified. With extracellular enzyme activity, the activity appeared in most enzymes. In particular, all the strains showed similar abilities for alkaline phosphatase, esterase (C4), acid phosphatase, and naphtol-AS-BI-phosphohydrolase production. This result was observed because the genus Bacillus secreted various organic substances, antibiotics, and extracellular enzymes. Therefore, through the results of this study, we suggest the possibility of using strains contributing to the improvement of the soil environment as microbial agents.

• The Journal of Internal Korean Medicine
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• v.42 no.1
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• pp.25-39
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• 2021

Objective: The purpose of this study was to investigate the effect of Lonicera Japonica Thunberg (LJT) on the inflammatory factor expression associated with atherosclerosis in human umbilical vein endothelial cells (HUVECs). Methods: After treatment with LJT in HUVEC which is treated with TNF-α, we measured the expression levels of biomarkers (MCP-1, ICAM-1, VCAM-1, KLF2, and eNOS), mRNA (CCL2, ICAM1, VCAM1, KLF2, and NOS3), and the proteins (MCP-1, ICAM-1, VCAM-1, KLF2, eNOS, ERK, JNK, and p38). Results: 1. Compared to the control, LJT significantly reduced MCP-1 and VCAM-1 levels at concentrations of 100, 200, and 400 ㎍/ml and ICAM-1 expression at 200 and 400 ㎍/ml compared to the control. It increased KLF2 levels at all three concentrations, but not significantly, while eNOS expression was significantly increased at 400 ㎍/ml. 2. LJT was seen to significantly reduce the expression of CCL2, ICAM1, and VCAM1 mRNA at concentrations of 100, 200, and 400 ㎍/ml compared to the control. In contrast, significantly increased KLF2 and NOS3 mRNA levels were observed at 400 ㎍/ml and at 200 and 400 ㎍/ml, respectively. 3. Compared to the control, LJT significantly reduced the protein expression of MCP-1 and VCAM-1 at 200 and 400 ㎍/ml and of ICAM-1 at 400 ㎍/ml. In addition, it increased both KLF2 and eNOS protein levels at 200 and 400 ㎍/ml. Although LJT did not have an effect on ERK expression in comparison with the control, it significantly reduced JNK levels at 200 and 400 ㎍/ml and p38 levels at 400 ㎍/ml. Conclusions: These results suggest that LJT has an effect on the inhibition of inflammatory factor expression associated with atherosclerosis in HUVECs which could contribute to the prevention of cardiovascular and cerebrovascular diseases.

• Journal of the Korean earth science society
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• v.40 no.2
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• pp.109-118
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• 2019

Cloud-aerosol interactions are considered to be one of the most important forcing mechanisms in the climate system. However, there is considerable disagreement on the magnitude and even on the sign of how aerosol perturbations affect cloud fraction and lifetime. Furthermore, aerosol effects on clouds and precipitation are not readily separable from the effects of meteorology. This review paper summarizes the study of precipitation susceptibility $S_o$, which qualifies how aerosol perturbations alter the magnitude of the precipitation rate (R) while minimizing the effects of macrophysical factors such as cloud depth (H) and liquid water path (LWP). The analysis shows that the precipitation susceptibility $S_o$ for the warm marine boundary layer clouds is insensitive to aerosol perturbations at low LWP (equivalently low H). However, R decreases as aerosols increase at intermediate LWP. This is because aerosols act as cloud seed and produce numerous small-sized particles, which impede the collision and coalescence process that leads to precipitation. At high LWP, $S_o$ decreases with increasing LWP as there are enough water contents in the clouds. The LWP or H dependent $S_o$ behavior differs depending on the predominant cloud physics processes in the clouds.

• Journal of Conservation Science
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• v.34 no.6
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• pp.443-458
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• 2018

An archive is a collection of documents or records. Currently, most archived documents are made of paper. Paper is susceptible to biological damage and deterioration due to its material properties. To control the biological damage, treatment with chemical disinfectants and control of the storage environment are often used. In government-controlled bulk public archives, all documents are chemically sterilized before storage. However, an extremely large quantity of public records have been produced, and storage space and conservation management are gradually reaching their limits. In this study, 60 species of microbes were identified using a genetic method. We successfully applied the adenosine triphosphate (ATP) bioluminescence method to detect microbial contamination on paper documents. A calibration curve of the ATP bioluminescence as a function of the microbe quantity was obtained, and the microbial activity on non-sterilized paper archives from 1951 was analyzed using an ATP luminometer. It was found that the microbial activity was suppressed or reduced in climate-controlled storage environments at $22^{\circ}C$ and 55% relative humidity. We anticipate that these results will be used to establish selective sterilization systems for government-controlled bulk public archives.