• Title/Summary/Keyword: Kim Dong-hwan

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The Effect of Hydrolyzed Jeju Ulva pertusa on the Proliferation and Type I Collagen Synthesis in Replicative Senescent Fibroblasts (제주 구멍갈파래 가수분해물에 의한 노화된 섬유아세포 증식 및 콜라겐 합성증진 효과)

  • Ko, Hyun Ju;Kim, Gyoung Bum;Lee, Dong Hwan;Lee, Geun Soo;Pyo, Hyeong Bae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.3
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    • pp.177-186
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    • 2013
  • Skin dermal fibroblast is the major collagen-producing cell type in human skin. As aging process continues in human skin, collagen production is reduced and fragmentation is increased, which is initiated by matrix metalloproteinase-1 (MMP-1). This imbalance of collagen homeostasis impairs the structure and function of dermal collagenous extracellular matrix (ECM), thereby promoting skin aging. Cysteine-rich protein 61 (CCN1), a member of the CCN family, negatively regulates collagen homeostasis in primary human skin dermal fibroblast cells. It is known in aging fibroblast cells that elevated CCN1 expression substantially reduces type I procollagen and concurrently increases MMP-1, which initiates fibrillar collagen degradation. And proliferation rate of aging fibroblast cells is reduced compared to the pre-aging fibroblast cells. In this study, we confirmed that the replicative senescence dermal fibroblast cells increased the expression levels of MMP-1 and decreased the production of type I procollagen. Our results also showed that the replicative senescence dermal fibroblast cells increased in the expression of CCN1 and decreased in the proliferation rate. Hydrolyzed Ulva pertusa extracts are the materials to improve photo-aging by reducing the expression of MMP-1 that was increased by ultraviolet and by promoting the synthesis of new collagen from fibroblast cells. In this study, we also investigated the hydrolyzed U. pertusa extract to see whether it inhibits CCN1 protein expression in the senescence fibroblasts. Results showed that the hydrolyzed U. pertusa extract inhibited the expression of MMP-1 and increased the production of type I procollagen in the aging skin fibroblast cells cultured. In addition, the proteins that regulate collagen homeostasis CCN1 expression were greatly reduced. The hydrolyzed U. pertusa extract increased the proliferation rate of the aging fibroblast cells. These results suggest that replicative senescent fibroblast cells may be used in the study of cosmetic ingredients as a model of the natural aging. In conclusion, the hydrolyzed U. pertusa extract can be used in anti-wrinkle functional cosmetic material to improve the natural aging skin care as well as photo-aging.

The Change of Seedling Emergence of Abies koreana and Altitudinal Species Composition in the Subalpine Area of Mt. Jiri over Short-Term(2015-2017) (지리산 아고산대의 단기간(2015-2017)에 걸친 구상나무 치수 발생 및 고도별 종구성 변화)

  • Kim, Ji Dong;Park, Go Eun;Lim, Jong-hwan;Yun, Chung Weon
    • Korean Journal of Environment and Ecology
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    • v.32 no.3
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    • pp.313-322
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    • 2018
  • To investigate the changing patterns of sub-alpine forest vegetation due to climate change requires accumulation of contiguous reference data and continuous monitoring. Furthermore, it is crucial to monitor short-term ecological change of lower level vegetation to understand the trend of long-term vegetation change. Therefore, this study carried out a vegetation survey and tree diameter measurement in 36 plots of Mt. Jiri inhabited by Abies koreana species from 2015 to 2017 to examine the short-term dynamics of Abies koreana seedling and the change of vegetation distribution according to altitude. We analyzed the importance value and MIV (mean importance value) of major species by each stratum as well as the importance value and species diversity index of major species and the change of seedling population by altitude. The results showed that Abies koreana had the highest importance value on tree layer, Rhododendron schlippenbachii on shrub layer and Tripterygium regelii on herb layer. MIV was high in the order of Abies koreana, Rhododendron schlippenbachii and Acer pseudosieboldianum. Regarding the species composition and species diversity index (H') along the altitudinal gradient, Sasa borealis showed high MI and low H' in the elevation less than 1,500 m, and IV of Tripterygium regelii and H' of herb layer were high in the elevation of 1,700 - 1,800 m. Abies koreana seedling decreased by 22.4% from 1,250 n/ha in 2015 to 970 n/ha in 2017 (p <0.05) throughout the investigated area. The decline rate along seedling and sapling height were 22.9% in less than 10 cm, 3.4% in 10-30 cm, 8.9% in 30-50 cm, 39.3% in 50-100 cm, and 55.1% more than 100 cm. Few of A. koreana seedlings appeared due to the dominance of Sasa borealis in the elevation of 1,500 m or less and due to the dominance and high species diversity of Tripterygium regelii in the elevation of 1,700-1,800 m. On the other hand, many of A. koreana seedlings appeared in the elevation of 1,600-1,700 m due to no distribution of S. borealis and T. regelii species in that altitude range. Therefore, we concluded that those seedlings and saplings of A. koreana could be more stable in the altitude of 1,600-1,700 m.

The Three Dimensional Analysis on Nasal Airway Morphology in Class III Malocclusion (골격성 III급 부정교합자의 Nasal Airway 형태에 관한 3차원적 분석 연구)

  • Kim, Moon-Hwan;Lee, Jin-Woo;Cha, Kyung-Suk;Chung, Dong-Hwa
    • Journal of Dental Rehabilitation and Applied Science
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    • v.24 no.4
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    • pp.389-403
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    • 2008
  • In Angle's Class III malocclusion, which has higher incidence in Korean than Western, depressed midfacial profile with protruded lower lips and mandible may give rise to many functional, esthetic, psychological, social problems. Due to the different malocclusion incidence according to racial differences, many previous studies focused on the relationship between Class II malocclusion and nasal airway obstruction. Previous studies used lateral cephalography which has limitations of 2 dimensional image with projection error and identification error. Therefore, the purpose of this study was to analyze morphologic differences in the nasal airway between normal occlusion and Angle's Class III malocclusion patients using 3-dimensional facial computed tomography. Thirteen normal occlusion(7 men and 6 women) and sixteen skeletal Class III(7 men and 9 women) patients were selected and 3-dimensional facial computed tomography taking was performed. Comparison between two group in volume and sectional area of nasal airway were carried out. The results were followed. 1. In the comparison of absolute nasal airway volume, oropharyngeal space of experimental group were larger than control group but there are no significant difference in other. 2. In the comparison of relative nasal airway volume, oropharyngeal space of experimental group were larger than control group but there are no significant difference in other. 3. In the oropharyngeal space width on frontal and lateral view, the similar tendency was revealed between two groups. 4. In the lateral curvature of nasal airway, the similar tendency was revealed between two groups.

Valuation of Mining Investment Projects by the Real Option Approach - A Case Study of Uzbekistan's Copper Mining Industry - (실물옵션평가방법에 의한 광산투자의 가치평가 -우즈베키스탄 구리광산업의 사례연구를 중심으로-)

  • Makhkamov, Mumm Sh.;Kim, Dong-Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.6
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    • pp.1634-1647
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    • 2007
  • "To invest or not to invest?" Most business leaders are frequently faced with this question on new and ongoing projects. The challenge lies in deciding what projects to choose, expand, contract, defer, or abandon. The project valuation tools used in this process are vital to making the right decisions. Traditional tools such as discounted cash flow (DCF)/net present value (NPV) assume a "fixed" path ahead, but real world projects face uncertainties, forcing us to change the path often. Comparing to other traditional valuation methods, the real options approach captures the flexibility inherent to investment decisions. The use of real options has gained wide acceptance among practitioners in a number of several industries during the last few decades. Even though the options are present in all types of business decisions, it is still not considered as a proper method of valuation in some industries. Mining has been comparably slow to adopt new valuation techniques over the years. The reason fur this is not entirely clear. One possible reason is the level and types of risks in mining. Not only are these risks high, but they are also more numerous and involve natural risks compared with other industries. That is why the purpose of this study is to deal with a more practical approach to project valuation, known as real options analysis in mining industry. This paper provides a case study approach to the copper mining industry using a real options analysis. It shows how companies can minimize investment risks, exercise flexibility in decision making and maximize returns.

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Quality Characteristics and Antioxidant Activity of Mulberry Leaf Tea Fermented by Monascus pilosus (Monascus pilosus로 발효시킨 뽕잎차의 품질특성과 항산화능)

  • Lee, Sang-Il;Lee, Ye-Kyung;Choi, Jong-Keun;Yang, Seung-Hwan;Lee, In-Ae;Suh, Joo-Won;Kim, Soon-Dong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.5
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    • pp.706-713
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    • 2012
  • This study was carried out to investigate the contents of monacolin K and citrinin, along with the sensory quality and antioxidant activity of mulberry leaf tea fermented by $Monascus$ $pilsous$ (FMM). Total monacolin K content of FMM was 0.058%, but citrinin was not detected. Redness of brewed FMM was remarkably higher than that of unfermented mulberry leaf tea (UFM). In sensory evaluation of brewed FMM, while astringent taste and savory taste were lower, flavor, color, and overall acceptability were significantly higher than those of UFM. Total polyphenol contents of UFM and FMM were 83.1 and 23.61 mg/g (dry basis), total flavonoid contents of UFM and FMM were 17.96 and 3.99 mg/g (dry basis), respectively. Xanthine oxidase (XO) inhibitory activity and superoxide dismutase (SOD)-like activity of FMM were lower than those of UFM. Electron-donating ability and ferric-reducing antioxidant power of FMM were slightly lower than those of UFM. However, the antioxidant activities of FMM per polyphenol content were markedly higher than those of UFM. These results suggest that FMM may scavenge excessive reactive oxygen spices (ROS) via inhibition of XO and SOD-like activity. Furthermore, FMM demonstrated relatively higher acceptability and antioxidant ability along with functionality of $Hongguk$ (red yeast rice), and therefore could be utilized to prevent various ROS-induced diseases.

The Variation Characteristics of Groundwater Level with Distance from Shoreline in the Jeju Island (제주도 지역의 해안선에서 이격거리에 따른 지하수위 변동특성)

  • Kang, Dong-Hwan;Yang, Sung-Il;Kim, Tae-Yeong;Park, Hyun-Joo;Kwon, Byung-Hyuk
    • The Journal of Engineering Geology
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    • v.18 no.2
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    • pp.167-176
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    • 2008
  • The variation characteristics of groundwater level with distance from shoreline at Jeju Island was investigated using groundwater level data monitored from 257 wells for dry season (December 1998) and wet season (July 1997), respectively. Groundwater levels of the dry season were $7.46{\sim}203.8\;m$ with an average of 60.49 m, while those of the wet season were $4.01{\sim}204.10\;m$ with an average of 57.66 m. Groundwater level of the dry season was higher than that of the wet season, which was caused by heavy rains between June and October, 1998 at the Jeju Island. Correlation coefficients between altitude and groundwater level for dry and wet seasons were above 0.86, and those between dry season and wet season groundwater levels were very high above 0.95. 257 groundwater level data were classified at an interval of 500 m. Average values for altitude, groundwater levels and distance from shoreline were calculated for 17 intervals. Altitude and groundwater level fur dry and wet seasons at $0{\sim}4\;km$ intervals were increased with distance from shoreline, but those at $4{\sim}9\;km$ intervals were irregularity. Linear functions of the groundwater level for dry and wet seasons as distance from shoreline were estimated, and the coefficient of determinant at $0{\sim}4\;km$ interval data was higher than it at $0{\sim}9\;km$ interval data. Increasing rate of groundwater level at $0{\sim}4\;km$ intervals was more 2 times than it at $0{\sim}9\;km$ intervals. This results are caused by linear increase of groundwater level to 4 km from shoreline and by irregularity of groundwater level at the $4{\sim}9\;km$ intervals.

Changes in Growing Period and Productivity under Double Cropping of Spring Potato and Summer Cereals in Paddy Fields of Southern Korea (남부지역 논에서 봄감자와 하작물 이모작에 따른 생육기간 및 생산성 변화)

  • Seo, Jong-Ho;Hwang, Chung-Dong;Choi, Weon-Young;Bae, Hyeon-Kyung;Kim, Sang-Yeol;Oh, Seong-Hwan
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.4
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    • pp.459-468
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    • 2019
  • Changes in growing periods and productivities of crops under double cropping of potato-rice, potato-soybean and potato-maize, were investigated at the Paddy Experimental Fields in Miryang City from 2015 to 2018. Spring potatoes planted in early March showed a yield of 2.1-2.3 ton/10a and a period of 90 days. In double cropping, growing period of rice, soybean, and maize was about 130, 125 and 115 days, respectively. The potato yield obtained was as much as 616, 330 and 815 kg/10a under double cropping with rice, soybean and maize, respectively. It is beneficial to sow the spring potatoes as early as possible to increase the yield and to secure the growing period of sequential crops. The introduction of summer medium-late variety grain crops into double cropping of spring potato and rice as well as into double cropping of spring potato and soybean/maize, was possible because of no sowing in the fall and plants were able to reach the heading growth stage before the safe heading limit of rice in particular. In the case of maize, the growth period was different according to the change in temperature over the year. The introduction of upland crops such as soybeans and maize instead of rice improved soil physicochemical properties in a short period of time, contributing to the increase of spring potato yields, but there was also a risk of damage by successive cropping for more than three years. Spring potato-maize showed higher yield in terms of starch production, and spring potato-soybean was found to be advantageous for net income.

Behavior and Decomposition Velocity of Pollutants on Various Forms from Domestic Sewage in Small-scale Sewage Treatment Plant by Natural Purification Method (자연정화공법에 의한 농촌 전원독립가구 하수처리장에서 하수 중 오염물질의 존재형태별 거동과 분해속도)

  • Seo, Dong-Cheol;Kim, Hyung-Jun;Park, Woo-Young;Lim, Jong-Sir;Hwang, Seung-Ha;Park, Chan-Hoon;Choi, Jeong-Hwan;Lee, Hong-Jae;Lee, Do-Jin;Cho, Ju-Sik;Heo, Jong-Soo
    • Korean Journal of Environmental Agriculture
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    • v.27 no.1
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    • pp.18-26
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    • 2008
  • Behavior and decomposition velocity of pollutants on various forms from domestic sewage in sewage treatment plant were investigated in order to obtain the basic data for improving the removal efficiency of pollutants and to reduce the area in constructed wetland by natural purification method. The removal amounts of BODs and CODs in aerobic bed were significantly higher than those of the other beds. In aerobic bed, the removal amounts of IBOD and ICOD were more than those for SBOD and SCOD, respectively, whereas the removal amounts of BODs and CODs in anoxic and anaerobic beds were little different. The removal amounts of SSs in aerobic bed were also higher than those for the other beds, and the removal amounts of VSS in all beds were more than those for FSS. The removal amounts of DTN and DTP in all beds were more than those for STN and STP, respectively. In addition, the decomposition velocities of TBOD, TCOD and TSS in aerobic bed were 30.79, 17.15 and 29.96 $day^{-1}$. Moreover, the decomposition velocities of BODs, CODs and SSs in aerobic bed were very rapid than those in the other beds. On the other hand, the decomposition velocities of BODs, CODs and SSs in anoxic and anaerobic beds were a little different regardless of the forms of pollutant. The decomposition velocities constants of T-N in aerobic, anoxic and anaerobic beds were 4.78, 0.12 and 0.10 $day^{-1}$, respectively. Moreover, the decomposition velocities constants of T-P in aerobic, anoxic and anaerobic beds were 13.09, 0.12 and 0.13 $day^{-1}$ respectively. The decomposition velocity of T-Ns and T-Ps in aerobic bed were slightly rapid than those in the other beds, whereas the decomposition velocities of T-Ns and T-Ps in anoxic and anaerobic beds were slightly different regardless of the forms of pollutant.

Effect of Organic Matter and Moisture Content on Reduction of Cr(VI) in Soils by Zerovalent Iron (영가철에 의한 토양 Cr(VI) 환원에 미치는 유기물 및 수분함량 영향)

  • Yang, Jae-E.;Lee, Su-Jae;Kim, Dong-Kuk;Oh, Sang-Eun;Yoon, Sung-Hwan;Ok, Yong-Sik
    • Korean Journal of Environmental Agriculture
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    • v.27 no.1
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    • pp.60-65
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    • 2008
  • Current soil remediation principles for toxic metals have some limitations even though they vary with different technologies. An alternative technology that transforms hazardous substances into nonhazardous ones would be environmentally beneficial. Objective of this research was to assess optimum conditions for Cr(VI) reduction in soils as influenced by ZVI(Zero-Valent Iron), organic matter and moisture content. The reduction ratio of Cr(VI) was increased from 37 to 40% as organic matter content increased from 1.07 to 1.75%. In addition, Cr(VI) concentration was reduced as soil moisture content increased, but the direct effect of soil moisture content on Cr(VI) reduction was less than 5% of the Cr(VI) reduction ratio. However, combined treatment of ZVI(5%), organic matter(1.75%) and soil moisture(30%) effectively reduced the initial Cr(VI) to over 95% within 5 days and nearly 100% after 30 days by increasing oxidation of ZVI and concurrent reduction of Cr(VI) to Cr(III). The overall results demonstrated that ZVI was effective in remediating Cr(VI) contaminated soils, and the efficiency was synergistic with the combined treatments of soil moisture and organic matter.

Dietary Effects of Post-fermented Green Tea by Monascus pilosus on the Body Weight, Serum Lipid Profiles and the Activities of Hepatic Antioxidative Enzymes in Mouse Fed a High Fat Diet (Monascus pilosus로 발효시킨 후발효 녹차가 고지방 식이 마우스의 체중과 혈청 지방함량 및 간 조직 항산화계 효소활성에 미치는 영향)

  • Lee, Sang-Il;Lee, Ye-Kyung;Kim, Soon-Dong;Yang, Seung-Hwan;Suh, Joo-Won
    • Journal of Applied Biological Chemistry
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    • v.55 no.2
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    • pp.85-94
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    • 2012
  • The anti-obese, hypolipidemic and hepatoprotective effects of post-fermented green tea by Monascus pilosus was tested with mice fed with high-fat diet for 7 weeks. The body weight gain and feed efficiency ratio (FER) in normal control group (NC), CHA (2% non-fermented green tea powder supplemented high-fat diet group) and mCHA (2% green tea powder post-fermented by M. pilosus supplemented high fat diet group) groups were significantly lower than those of high fat diet control group (HC). Epididymal fat weight in mCHA and NC were significantly lower than HC. The hepatic lipid peroxide was dramatically higher in HC than that of NC and was significantly lower in CHA and mCHA. In addition, dehydrogenase type activity of xanthine oxidoreductase in HC was lower than that of NC, but significantly higher than CHA and mCHA. In histopathological findings, hepatic fat accumulation in HC was higher than that of NC, CHA and mCHA. Antiobese, hypolipidemic and antifatty liver effect of green tea powder post-fermented by M. pilosus was slightly higher than that of non-fermented green tea. In conclusion, the constituents of green tea fermented by M. pilosus has been proven to not only inhibit obesity and hyperlipidemia but also decrease the hepatic fat accumulation in high fat diet-induced obese mice.