• The Korean Journal of Physiology and Pharmacology
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• v.19 no.3
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• pp.241-247
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• 2015

Ultraviolet (UV) radiation-induced loss of dermal extracellular matrix is associated with skin photoaging. Recent studies demonstrated that keratinocyte-releasable stratifin (SFN) plays a critical role in skin collagen metabolism by inducing matrix metalloproteinase 1 (MMP1) expression in target fibroblasts. In the present study, we examined whether SFN released from UVB-irradiated epidermal keratinocytes increases MMP1 release from dermal fibroblasts, and whether these events are affected by p-coumaric acid (p-CA), a natural phenolic compound with UVB-shielding and antioxidant properties. HaCaT cells were exposed to UVB in the absence and presence of p-CA, and the conditioned medium was used to stimulate fibroblasts in medium transfer experiments. The cells and media were analyzed to determine the expressions/releases of SFN and MMP1. UVB exposure increased SFN release from keratinocytes into the medium. The conditioned medium of UVB-irradiated keratinocytes increased MMP1 release from fibroblasts. The depletion of SFN using a siRNA rendered the conditioned medium of UVB-irradiated keratinocytes ineffective at stimulating fibroblasts to release MMP1. p-CA mitigated UVB-induced SFN expression in keratinocytes, and attenuated the MMP1 release by fibroblasts in medium transfer experiments. In conclusion, the present study demonstrated that the use of UV absorbers such as p-CA would reduce UV-induced SFN-centered signaling events involved in skin photoaging.

• The Korea Journal of Herbology
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• v.20 no.3
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• pp.19-27
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• 2005

Objectives : The antioxidant activities of Yeonkyo-san and its ingredient were investigated for industrial application. Methods : We experimented radical scavenging effect, superoxide dismutase and cytotoxicity effect of various cancer cell. Results : The result were obtained as follows : Primary testing of cytotoxicity of Yeonkyo-san and ingredient was done for G361. B16F10, MDA and A549 cell lines. Yeonkyo-san and ingredient water extract, ethanol extract showed cytotoxicity of over 90% respectively against cell line. The electron donating ability(EDA) of water extract from the Yeonkyo-san was higher than 60%, ethanol extract from the Yeonkyo-san was over 80% at 1000 ppm. The electron donating ability(EDA) of water extract and ethanol extract from the Yeonkyo-san ingredients were increased as well. SOD-like activity was high as 75% in 700 ppm, it was increased. All the other samples showed less than 40% SOD-like activity. Conclusions : The results indicated that water extract and ethanol extract of Yeonkyo-san and ingredient can be used as a natural ingredient with biological functions in cosmetic and food composition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.444-451
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• 1999

We performed this study to determine the radioprotective effect of Sam Ryung Baek Chul San (San Ling Bai Shu San), as a prescription of traditional Oriental medicine, and its major ingredients. Jejunal crypt survival, endogenous spleen colony formation, and apoptosis in jejunal crypt cells were investigated in irradiated mice with high and low dose of rays. Sam Ryung Baek Chul San administration before irradiation increased the formation of endogenous spleen colony(p<0.05) and reduced the frequency of radiation induced apoptosis(p<0.05). In the experiment on the effect of ingredients of Sam Ryung Baek Chul San, the result indicated that the extracts of Panax ginseng, Poria cocos and Coix lacryma jabi might have the major radioprotective effects. Although the mechanisms of these inhibitory effects remain to be elucidated, these results indicated that Sam Ryung Baek Chul San might be a useful radioprotector, especially since it is a relatively nontoxic natural product.

• Structural Engineering and Mechanics
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• v.25 no.4
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• pp.445-466
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• 2007

As the LNG (Liquefied Natural Gas) tank contains cryogenic liquid, realistic thermal analyses are of a primary importance for a successful design. The structural details of the LNG tank are so complicated that some strategies are necessary to reasonably predict its temperature distribution. The proposed heat transfer model can consider the beneficial effects of insulation layers and a suspended deck on temperature distribution of the outer concrete tank against cryogenic conditions simply by the boundary conditions of the outer tank model. To this aim, the equilibrium condition or heat balance in a steady state is utilized in a various way, and some aspects of heat transfer via conduction, convection and radiation are implemented as necessary. Overall thermal analysis procedures for the LNG tank are revisited to examine some unjustifiable assumptions of conventional analyses. Concrete and insulation properties under cryogenic condition and a reasonable conversion procedure of the temperature-induced nonlinear stress into the section forces are discussed. Numerical examples are presented to verify the proposed schemes in predicting the actual temperature and stress distributions of the tank as affected by the cryogenic LNG for the cases of normal operation and leakage from the inner steel tank. It is expected that the proposed schemes enable a designer to readily detect the effects of insulation layers and a suspended deck and, therefore, can be employed as a useful and consistent tool to evaluate the thermal effect in a design stage of an LNG tank as well as in a detailed analysis.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.2
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• pp.105-112
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• 2015

Resveratrol is a natural polyphenol. It protects skin from skin injury, ultraviolet radiation and pathogenic attack. This study is to find the optimum condition for the preparation of ethosome loading amount of resveratrol in ethosome. Ethosomes were prepared by modified hydrated liquid crystal method. Investigation of factors affecting the entrapment efficiency and particle size of ethosomes was carried out. The particle size of ethosome were measured by particle analyzer. The loading efficiency of resveratrol in ethosome was measured by HPLC. The particle sizes were 111.2 ~ 112.8 nm and the loading efficiency of resveratrol was 81.25 ~ 88.75%. The optimum conditions for the preparation of ethosome was obtained from of lecithin : resveratrol : cholesterol : ethanol at a weight ratio of 2.0 : 0.08 : 0.05 : 20.0.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.698-704
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• 1999

In this study, we evaluated the radioprotective effects of Kuei Pi Tang and its ingredients, as a prescription of traditional Oriental medicine. The jejunal crypt survival, endogenous spleen colony formation, and apoptosis in jejunal crypt cells were investigated in mice irradiated with high and low dose of ${\gamma}$ rays. In the mice administered with Kuei Pi Tang extract before irradiation, the jejunal crypts were protected significantly(p<0.005) and the frequency of radiation induced apoptosis was reduced(p<0.05). In the experiment on the effects of the ingredients of Kuei Pi Tang, the results indicated that the extract of Dangui(Angelica sinensis), Suanzaoren(Zizyphus valgaris), Rensan (Panax ginseng), Fuling(Poria cocos) and Muxiang(Saussurea lappa) might have a major radioprotective effect. Although the mechanisms of this inhibitory effect remain to be elucidated, these results indi cated that Kuei Pi Tang might be a useful radioprotector, especially since it is a relatively nontoxic natural product.

• Journal of the Korea Institute of Building Construction
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• v.17 no.1
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• pp.15-21
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• 2017

WHO reported that millions of people die every year because of diseases induced from environmental pollution. In 2012, approximately 7 million people were killed due to air pollution. Major cause of such pollution includes toxin, chemical waste, radiation and air pollution. Therefore, the significance and interest to indoor air quality has been continuously increased. Especially, the interest in radon, the ARC group 1 carcinogen, is rapidly increasing, and banning the use of construction materials that release radon, repairing aged buildings, and developing ventilators. To reduce the level of radon gas was inflowed to indoors and outdoors, this study is to research and develop a radon gas absorption board using absorbents. The absorbents utilized to absorb the radon gas were porous diatomite, natural zeolite, 4A zeolite and 13X zeolite and employed bentonite and illite, montmorillonites with the property of exchanging anions. As the main binder, magnesium oxide was used, with a content of 25% magnesium chloride.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.664-670
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• 2007

The propolis is natural product produced by honeybees and is known to have many biologically useful properties such as anti-microbial, anti-oxidative and anti-tumorigenic activity. However, its radio-protective property has not been well studied. To investigate radio-protective effect of propolis on mouse testis, mice were supplemented with propolis after 5 Gy irradiation. The histological changes of testis were detected by TEM. The results indicate that propolis may protect tissue deformation which is induced by 5 Gy of ionizing radiation. Furthermore, to elucidate the potential molecular mechanisms involved in radio-protective property of propolis, we performed microarray experiments using oligo DNA microarray. We found 65 up-regulated genes and 224 down-regulated genes, whose expression levels were affected more than 2-fold by propolis treatment in mice irradiated at 5 Gy. We confirmed microarray data with reverse transcription-PCR using gene specific primers. The results of RT-PCR are highly correlated with those of microarray. These results may help understanding molecular mechanisms of radioprotective effects by propolis in mouse model.

• Nuclear Engineering and Technology
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• v.51 no.6
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• pp.1638-1649
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• 2019

Top soil samples across the state of Kuwait numering ninety were collected and analysed using gamma-ray spectrometry, to evaluate the elemental concentration of $^{238}U$, $^{232}Th$ and $^{40}K$ and their depletion/enrichment. Results of elemental concentration ranges from 0.48 to 2.61 mg/kg, 0.87-5.23 mg/kg, and 0.24-2.23%, with a mean values of 1.39 mg/kg, 3.47 mg/kg, and 1.18%, for the $^{238}U$, $^{232}Th$ and $^{40}K$, respectively. Further analysis was conducted amongst the five identified soil types, i.e. Aquisalids (S1), Calcigypsids (S2), Petrocalcids (S3), Petrogypsids (S4), and torripsamment (S5). The highest radioactivity concentrations from both uranium and thorium were recorded in the S2 (Calcigypsids) soil, with a value of 1.71 (mg/kg) and 4.45 (mg/kg), respectively. Minimum and maximum values of $^{40}K$ are 1.1(%) and 1.27(%) and is prevalent in Aquisalids (S1) and Petrocalcids (S3) soil types, respectively. Ratios of elemental concentration for $^{232}Th/^{238}U$, $^{40}K/^{238}U$, $^{40}K/^{232}Th$ across the soil types are 2.53, 0.09 and 0.03, with a correlation coefficient of 0.92, 0.34, and 0.38, respectively. A progressively higher $^{232}Th/^{238}U$ ratio is observed moving south-wards, indicating lower $^{238}U$ content in soils from the south relative to the northern part. Overall results indicate Kuwait to be relatively an area with low level of natural radioactivity.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.3
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• pp.189-195
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• 2019

In this work, the flow and combustion characteristics using a 3-D numerical simulation was evaluated for a shale gas fueled combustor in a commercial class gas turbine. The Standard k-e turbulence model, 2 step methane oxidation mechanism, Finite rate/Eddy dissipation reaction model, DTRM radiation model were employed and validated well at the baseline condition (Natural Gas, Pilot Ratio 0.2). Based on the validated models, the combustion characteristics of shale gas was evaluated for three pilot ratios cases. It was found that NOx concentrations for all shale gas cases were less than the that for city gas, which imply that, at the selected PRs, the condition for combustion stability is satisfied. In addition, for higher PR, whereas the average temperatures at the exit are the same, the NOx increases. It means that diffusion combustion portion increases due to the higher PR.