• 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.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.336-343
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• 2018

This study was carried out to provide the technology of silvicultural practices and management for regeneration by sprouts in the oak forests distributed on the slope. A total of 1,451 stumps were examined for the following factors relative to the occurrence and growth of the sprouts: stump height & diameter; location & quantity and root collar diameter & height of arisen sprouts. The amount of sprouts deceased or increased as the stump diameter increased. However, it tended to increase with stump height. The difference in the stump height between direction of the upwards (DUS) and downward slopes (DDS) was occurred, because oak trees were felled lower based on direction of the upward for convenience of regeneration works on the slope. The number of sprouts was higher relatively in the stumps of DDS. The rate of arisen side and root sprouts was higher in the stumps of DDS and DUS, respectively. The stump height difference was found to affect the arisen part of sprouts. As a result of comparing the sprouts growth according to the arisen part, there was no difference in the stump of DUS, but the growth of side sprouts in the stump of DDS was higher than that of the root. In order to improve the quality of oak sprouts considering the distribution characteristics of the oak forests in South Korea, it is necessary to apply the silvicultural technique, making the cutting surface parallel with the slope to reduce the stump height difference, to suppress arising side sprouts.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.498-506
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• 2018

The purpose of this study is to examine the restorative effect of Semisulcospira libertina extract, on damaged liver cells induced by D-galactosamine in rats. Treatment of damaged liver cells with S. libertina extract significantly reduced local fatty degeneration, and inflammatory cell necrosis, to levels similar with the undamaged control group. In addition, S. libertina extracts were found to reduce plasma levels of liver damage indicator enzymes, such as AST, ALT, LDH and ALP, to control levels. It also reduced lipid peroxides, and lipid contents within damaged liver tissues. This suggests that S. libertina extract has a restorative effect on liver cells, thus reducing release of damage-associated liver enzymes, and oxidative degradation of lipids. Also, S. libertina extracts were found to be involved in recovery of damaged cells from inflammatory response by suppressing expression of $TNF-{\alpha}$, which leads to tissue injury and necrosis, whereas inducing expression of HO-1 that protects cells during inflammation. Thus, S. libertina extract restores liver tissue from necrosis and fibrosis, as well modulates expression of inflammation-related genes against liver damage. Our findings suggest that S. libertina extract is an effective medicinal resource, for improving and recovering liver cells from hepatic injury.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.3
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• pp.255-263
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• 2019

Isomaltol glycoside is a hydrophilic furanic glycoside in which the amino acids and sugars of ginseng are thermally denatured during red ginseng production. Various skin whitening tests were conducted on isomaltol glycoside containing a lot of red ginseng extract in order to investigate the skin whitening effect as a cosmetic raw material. We have tested melanin content assay in B16-F10 cells, zebrafish embryo pigmentation assay, mushroom tyrosinase inhibitory activity, western blot analysis to determine skin whitening activity of isomaltol glycosides. In the zebrafish melanin content assay, isomaltol glycoside decreased total melanin content by about 20% and zebrafish tyrosinase activity by about 10% after treatment with 50 and $100{\mu}g/mL$ compared to the untreated control group. Isomaltol glycoside also showed a concentration-dependent decrease in melanin content in B16-F10 melanoma. Furthermore, it increased the expression of MITF phosphorylation factors p-AKT and p-ERK in B16-F10 melanoma and decreased the concentration of MITF. It also inhibited tyrosinase, TRP-1 and TRP-2 expression. The content of isomaltol glycoside was about 3% in the ginseng extract and about 1% in the ginseng root. Thus, isomaltol glycoside is considered as one of the main components that exhibit the whitening activity of ginseng when considered quantitatively as whitening activity.

• Journal of Digital Convergence
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• v.17 no.8
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• pp.283-291
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• 2019

The aim of investigated the role of FABP5 in the hepatic lipogenesis and lipid metabolisms. Mice were overexpressed and silenced liver FABP5 using virus particles. Mice were fed a Western-type diet or regular chow for 1week and then sacrificed mouse after 24hr fasted. Liver homogenates were used for protein analysis by Western blot and mRNA levels by RT-PCR. Hepatic and serum lipids were analysed by thin-layer chromatography. Mice fed a Western-type or high saturated fat diet revealed large increases in FABP5 expression. However, FABP5 mRNA levels were drastically reduced under fasted. Hepatic TG was significantly increased FABP5-OEAV mice, but a significantly decreased hepatic free cholesterol under fed. The discovered a substantial decrease in hepatic TG mass with FABP5 silencing. In these data, presented evidence for an important role of FABP5 in hepatic lipogenesis and hepatic TG storage. FABP5 may also be a potential target in the treatment of NAFLD, metabolic syndrome, and obesity. Furthermore, studies to which transcription factors are involved in FABP5 expression and regulation.

• Journal of Nutrition and Health
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• v.54 no.2
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• pp.224-237
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• 2021

Purpose: Paeonia Radix Alba is a traditional herbal medicine used to treat the liver and the spleen. Many studies have reported that Paeonia Radix Alba extract (PR) affects liver injury, but there has been no study on liver injuries induced by thioacetamide (TAA). Therefore, we aimed at evaluating the effect of PR on a TAA-induced acute liver injury (ALI) model. Methods: The antioxidant activity of PR was assayed by the content of total polyphenol, total flavonoid, 1,1-diphenyl-2'-picrylhydrazyl (DPPH), and 2,2'-azino-bis (3-ethylbenzo-thiazoline-6-sulfonicacid) (ABTS) radical scavenging activities in vitro test. ALI was induced via-intraperitoneal injection of TAA (200 mg/kg body weight) for three consecutive days. Also, silymarin (100 mg/kg body weight) and PR (100 or 200 mg/kg body weight) were administered at 1 hours 30 minutes prior to TAA treatment. The levels of ammonia, glutamic oxaloacetic transaminase (GOT), and glutamic pyruvic transaminase (GPT) were analyzed using an assay kit. The expressions of antioxidant proteins including Nrf2, Keap1, HO-1, SOD, catalase, and GPx-1/2 and oxidative stress-related proteins including NOX2, p47^phox, and p22^phox were evaluated by the western blot analysis. Results: PR showed excellent antioxidant activity in vitro. TAA administration increased the levels of ammonia, GOT, and GPT in the ALI control group compared to the normal group, whereas it was significantly reduced by PR pretreatment. Moreover, NADPH oxidase protein expressions were upregulated after TAA treatment, while the elevated expressions were inhibited by PR pretreatment. The expressions of antioxidant protein were downregulated in the ALI control group, whereas Nrf2 activation in the PR group was accompanied by increased levels of antioxidant enzymes. Conclusion: PR administration increased the antioxidant enzymes via activation of the Keap1/Nrf2 pathway and inhibited the protein levels of NADPH oxidase factors. Taken together, these results showed that PR treatment may be considered to ameliorate acute liver injury induced by TAA.