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Synergistic Inhibition of Aronia melanocarpa and Moringa oleifera Seed Extract on Experimental Atopic Dermatitis (아로니아 및 모링가 종자 복합물의 항아토피 상승효과)

  • Ki, Hyeon-Hui;Lee, Ji-Hyun;Moon, Kwang-Hyun;Lee, Jeong-Ho;Kim, Dae-Geun;Jeong, Kyung-Ok;Im, So-Yeon;Lee, Young-Mi;Kim, Dae-Ki
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.3
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    • pp.298-305
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    • 2017
  • Atopic dermatitis is a chronic, relapsing inflammatory skin disease. This study aimed to investigate the therapeutic benefits of Aronia melanocarpa (AM) and Moringa oleifera seed extract (MO) on experimental atopic dermatitis. We examined the effects of AM or MO and their combination on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis in BALB/c mice as well as tumor necrosis factor $(TNF)-{\alpha}$ and interferon $(IFN)-{\gamma}-stimulated$ HaCaT keratinocytes. Mice were orally treated with extract during repeated application of DNCB to shaved dorsal skin. Our results show that treatment with AM and MO in combination reduced histological manifestations such as epidermal hyperplasia and inflammatory cell infiltration. Furthermore, it significantly decreased skin thickness and serum immunoglobulin E (IgE) level compared to the AM or MO alone treated group. Combined extract of AM and MO suppressed expression of $TNF-{\alpha}/IFN-{\gamma}-induced$ T helper 2 (Th2) chemokines such as thymus and activation-regulated chemokine and macrophage-derived chemokine. To sum up, combination of AM and MO suppressed the inflammatory response and serum IgE as an indicator of several allergic diseases in DNCB-induced experimental atopic dermatitis and Th2 chemokine expression in HaCaT cells. This result suggests that combination of AM and MO could be a valuable strategy to improve atopic dermatitis.

The Distribution of Aerosol Concentration during the Asian Dust Period over Busan Area, Korea in Spring 2009 (2009년 봄철 부산지역 황사 기간 중 에어로솔 농도 분포)

  • Jung, Woon-Seon;Park, Sung-Hwa;Lee, Dong-In;Kang, Deok-Du;Kim, Dong-Chul
    • Journal of the Korean earth science society
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    • v.34 no.7
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    • pp.693-710
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    • 2013
  • This study investigates the distribution of suspended particulates during the Asian dust period in Busan, Korea in the spring of 2009. Weather map and automatic weather system (AWS) data were used to analyze the synoptic weather conditions during the period. Particulate matter 10, laser particle counter data, satellite images and a backward trajectories model were used to analyze the aerosol particles distribution and their origins. In Case 1 (20 February 2009), when the $PM_{10}$ concentration increased, the aerosol volume distribution of small ($0.3-1.0{\mu}m$) particles decreased, while the concentration of large ($1.0-10.0{\mu}m$) particles increased. When the $PM_{10}$ concentration decreased, the aerosol volume distribution was observed to decrease as well. The prevailing winds changed from weak northerly winds to strong southwesterly winds when the concentration of the large particles increased. The correlation coefficient between the $PM_{10}$ concentration and aerosol volume distribution of large particles showed a high positive value of over 0.9. The results from the trajectory model show that the Asian dust originated in the Gobi desert and the Nei Mongol plateau. In Case 2 (25 April 2009), when the $PM_{10}$ concentration increased, the aerosol volume concentration of small ($0.3-0.5{\mu}m$) particles decreased, but the concentration of large ($0.5-10.0{\mu}m$) particles increased. The opposite was observed when the $PM_{10}$ concentration decreased. The prevailing winds changed from northeasterly winds to southwesterly and northeasterly winds. The correlation coefficient between the $PM_{10}$ concentration and aerosol volume distribution of large particles ($1.0-10.0{\mu}m$) showed a high positive value of about 0.9. The results from the trajectory model show that the Asian dust originated in Manchuria and the eastern coast of China.

A Study on Singapore Startup Ecosystem using Regional Transformation of Isenberg(2010) (싱가포르 창업생태계 연구: Isenberg(2010) 프레임워크의 지역적 변용을 통한 질적 연구를 중심으로)

  • Kim, Soyeon;Cho, Minhyung;Rhee, Mooweon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.2
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    • pp.47-65
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    • 2020
  • With the era of the Fourth Industrial Revolution in sight, innovative business models utilizing new technologies are emerging, and startups are enjoying an abundance of opportunities based on the agility to respond to disruptive innovations and the opening to new technologies. However, what is most important in creating a sustainable start-up ecosystem is not the start-up itself, but the process of research-start-investment-investment-the leap to listing and big business-in order to build a virtuous circle of startups that leads to re-investment. To this end, the environment created in the hub area where start-ups were conducted is important, and these material and non-material environmental factors are described as being inclusive by the word "entrepreneurial ecosystem." This study aims to provide implications for Korea's entrepreneurial ecosystem through the study of the interaction of the elements that make up the start-up ecosystem and the relationship of ecosystem participants in Singapore. Singapore has been consistently mentioned as the top two Asian countries in assessing the start-up environment and business environment. In this process, six elements of the entrepreneurial ecosystem presented by Isenberg(2010)-policies, finance, culture, support, human resources, and market-are the best frameworks for analyzing entrepreneurial ecosystems in terms of well encompassing prior studies related to entrepreneurial ecosystem elements, and a model of regional transformation is formed focusing on some elements to suit Singapore, the target area of study. By considering that Singapore's political nature would inevitably have a huge impact on finance, Smart Nation policy was having an impact on university education related to entrepreneurship, and that the entrepreneurial networks and global connectivity formed within Singapore's start-up infrastructure had a significant impact on Singapore's start-up's performance, researches needed to look more at the factors of policy, culture and market. In addition, qualitative research of participants in the entrepreneurial ecosystem was essential to understand the internal interaction of the elements of the start-up ecosystem, so the semi-structured survey was conducted by visiting the site. As such, this study examined the status of the local entrepreneurial ecosystem based on qualitative research focused on policies, culture and market elements of Singapore's start-up ecosystem, and intended to provide implications for regulations related to start-ups, the role of universities and start-up infrastructure through comparison with Korea. This could contribute not only to the future research of the start-up ecosystem, but also to the creation of a start-up infrastructure, boosting the start-up ecosystem, and the establishment of the orientation of the start-up education in universities.

Determination of Target Clean-up Level and Risk-Based Remediation Strategy (위해성에 근거한 정화목표 산정 및 복원전략 수립)

  • Ryu, Hye-Rim;Han, Joon-Kyoung;Nam, Kyoung-Phile
    • Journal of Soil and Groundwater Environment
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    • v.12 no.1
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    • pp.73-86
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    • 2007
  • Risk-based remediation strategy (RBRS) is a consistent decision-making process for the assessment and response to chemical release based on protecting human health and the environment. The decision-making process described integrates exposure and risk assessment practices with site assessment activities and remedial action selection to ensure that the chosen actions are protective of human health and the environment. The general sequences of events in Tier 1 is as follows: initial site assessment, development of conceptual site model with all exposure pathways, data collection on pollutants and receptors, and identification of risk-based screening level (RBSL). If site conditions do not meet RBSL, it needs further site-specific tier evaluation, Tier 2. In most cases, only limited number of exposure pathways, exposure scenarios, and chemicals of concern are considered the Tier 2 evaluation since many are eliminated from consideration during the Tier 1 evaluation. In spite of uncertainties due to the conservatism applied to risk calculations, limitation in site-specific data collections, and variables affecting the selection of target risk levels and exposure factors, RBRS provides us time- and cost-effectiveness of the remedial action. To ensure reliance of the results, the development team should consider land and resource use, cumulative risks, and additive effects. In addition, it is necessary to develop appropriate site assessment guideline and reliable toxicity assessment method, and to study on site-specific parameters and exposure parameters in Korea.

Time Dependent Evaluation of Corrosion Free Life of Concrete Tunnel Structures Based on the Reliability Theory (해저 콘크리트 구조물의 신뢰성 이론에 의한 시간 의존적 내구수명 평가)

  • Pack, Seung Woo;Jung, Min Sun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.3
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    • pp.142-154
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    • 2011
  • This study predicted the probability of corrosion initiation of reinforced concrete tunnel boxes structures using the Monte Carlo Simulation. For the inner wall and outer wall in the tunnel boxes, exposed to airborne chloride ion and seawater directly respectively, statistical values of parameters like diffusion coefficient D, surface chloride content $C_s$, cover depth c, and the chloride threshold level $C_{lim}$ were examined from experiment or literature review. Their average values accounted for $3.77{\times}10^{-12}m^2/s$, 3.0% by weight of cement, 94.7mm and 45.5mm for outer wall and inner wall, respectively, and 0.69% by weight of cement for D, $C_s$, c, and $C_{lim}$, respectively. With these parametric values, the distribution of chloride contents at rebar with time and the probability of corrosion initiation of the tunnel boxes, inner wall and outer wall, was examined by considering time dependency of chloride transport. From the examination, the histogram of chloride contents at rebar is closer to a gamma distribution, and the mean value increases with time, while the coefficient of variance decreases with time. It was found that the probability of corrosion initiation and the time to corrosion were dependent on the time dependency of chloride transport. Time independent model predicted time to corrosion initiation of inner wall and outer wall as 8 and 12 years, respectively, while 178 and 283 years of time to corrosion was calculated by time dependent model for inner wall and outer wall, respectively. For time independent model, the probability of corrosion at 100 years of exposure for inner wall and outer wall was ranged 59.5 and 95.5%, respectively, while time dependent model indicated 2.9 and 0.2% of the probability corrosion, respectively. Finally, impact of $C_{lim}$, including values specified in current codes, on the probability of corrosion initiation and corrosion free life is discussed.

Comparative Analysis of Ecological Health Conditions Before and After Ecological Restoration in Changwon Stream and Nam Stream (창원천.남천에서 생태복원 전.후의 생태건강도 비교평가)

  • Kim, Hyun-Jeong;Lee, Sang-Jae;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.307-318
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    • 2010
  • This study was to analyze the ecological conditions, based on physical habitat, chemical, and biological conditions before (2006, 2007) and after ecological restoration (2009) in five sites of Changwon Stream (CS) and six sites of Nam Stream (NS), respectively, and then to compare ecological health between the two period. The analysis of ecological health was based on the multimetric models of Index of Biological Integrity (IBI) and Qualitative Habitat Evaluation Index (QHEI) along with water chemistry in the streams. For the study, the models of IBI and QHEI were modified as 8 and 11 metric attributes, respectively. For the evaluations, the survey was conducted in the period of 2006~2007 before the restoration and in 2009 after the restoration by the city. Chemical conditions, based on conductivity, in both streams showed a typical longitudinal declines along the axis of the upstream-to-downstream. There were no significant differences (p>0.05) in water quality between the two periods. Values of IBI in the CS and NS averaged 21.6 and 19.7, respectively, indicating a C grade in the criteria of Ministry of Environment, Korea, and there was no significant differences in the IBI between the two periods. Values of QHEI after the restoration averaged 29.2 and 63.2 in the CS and NS, respectively and the values decreased markedly especially, in the NS (35.3) after the restoration. The habitat disturbance was mainly attributed to destructions (i.e., the narrower width of riparian vegetation and higher substrate exposure by the air) of artificial materials by massive flood in 2009. Overall, our results suggest that the restoration was not effective in the two streams between the two periods, even if the budget was used a lot and that such ecological restoration, not considered the natural disaster, may not effect for the stream restoration.

Administration of Triticum aestivum Sprout Water Extracts Reduce the Level of Blood Glucose and Cholesterol in Leptin Deficient ob/ob Mice (Leptin 결핍 ob/ob 마우스에서 소맥엽 추출물의 혈당 강하 및 혈중 콜레스테롤에 미치는 효과)

  • Lee, Sun-Hee;Lim, Sung-Won;Mihn, Nguyen Van;Hur, Jung-Mu;Song, Bong-Joon;Lee, Young-Mi;Lee, Hoi-Seon;Kim, Dae-Ki
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.3
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    • pp.401-408
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    • 2011
  • Type 2 diabetes mellitus (NIDDM) is a metabolic disorder that is characterized by high blood glucose in the context of insulin resistance and relative insulin deficiency. In order to control the type 2 diabetes mellitus, anti-hyperglycemic effect of Triticum aestivum L. water extracts (TAWE) was investigated in 7 week old male diabetic C57BL6/J-ob/ob mice. For the experiments, the diabetic animal model ob/ob mice and non-diabetic animal model lean mice were divided into 3 groups: non-treatment control group (Control), and two experimental groups orally treated with 25 or 100 mg/kg/day dose of TAWE (TAWE-25 and TAWE-100, respectively). The lean mice were used as the non-diabetic normal control. TAWE was orally administrated for 6 weeks and the diabetic clinical markers, including blood glucose level, body weight, organs weight and insulin level were determined. The oral administration of TAWE-100 in ob/ob diabetic mice significantly decreased blood glucose level (78.4%) and body weight (11.9%) compared with diabetic control group. The weights of organs, including spleen, liver, kidneys, heart and lung were not different among groups, while the treatments of TAWE-100 in ob/ob diabetic mice significantly reduced blood total cholesterol (24.35%) and triglyceride (23.97%) levels compared with the diabetic control group. The levels of serum insulin and glucose tolerance were improved after TAWE-100 treatment in ob/ob diabetic mice. Moreover, the immunohistochemical staining for insulin detection in pancreatic islet $\beta$-cells expressed high level of insulin in TAWE-100 treated ob/ob mice. From the above results, the intake of TAWE may be effective in anti-hyperglycemia by the attenuation of glucose and lipid levels. TAWE-containing diets or drugs may be beneficial for controlling diabetes mellitus type 2 in human.

The Generation of Westerly Waves by Sobaek Mountains (소백산맥에 의한 서풍 파동 발생)

  • Kim, Jin wook;Youn, Daeok
    • Journal of the Korean earth science society
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    • v.38 no.1
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    • pp.24-34
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    • 2017
  • The westerly waves generation is described in the advanced earth science textbook used at high school as follows: as westerly wind approaches and blows over large mountains, the air flow shows wave motions in downwind side, which can be explained by the conservation of potential vorticity. However, there has been no case study showing the phenomena of the mesoscale westerly waves with observational data in the area of small mountains in Korea. And thus the wind speed and time persistency of westerly winds along with the width and length of mountains have never been studied to explain the generation of the westerly waves. As a first step, we assured the westerly waves generated in the downwind side of Sobaek mountains based on surface station wind data nearby. Furthermore, the critical or minimum wind velocity of the westerly wind over Sobaek mountains to generate the downwind wave were derived and calcuated tobe about $0.6m\;s^{-1}$ for Sobaek mountains, which means that the westerly waves could be generated in most cases of westerly blowing over the mountains. Using surface station data and 4-dimensional assimilation data of RDAPS (Regional Data Assimilation and Prediction System) provided by Korea Meteorological Agency, we also analyzed cases of westerly waves occurrence and life cycle in the downwind side of Sobaek mountains for a year of 2014. The westerly waves occurred in meso-${\beta}$ or -${\gamma}$ scales. The westerly waves generated by the mountains disappeared gradually with wind speed decreasing. The occurrence frequency of the vorticity with meso-${\beta}$ scale got to be higher when the stronger westerly wind blew. When we extended the spatial range of the analysis, phenomena of westerly waves were also observed in the downwind side of Yensan mountains in Northeastern China. Our current work will be a study material to help students understand the atmospheric phenomena perturbed by mountains.

The Effect of the Surfactant on the Migration and Distribution of Immiscible Fluids in Pore Network (계면활성제가 공극 구조 내 비혼성 유체의 거동과 분포에 미치는 영향)

  • Park, Gyuryeong;Kim, Seon-Ok;Wang, Sookyun
    • Economic and Environmental Geology
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    • v.54 no.1
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    • pp.105-115
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    • 2021
  • The geological CO2 sequestration in underground geological formation such as deep saline aquifers and depleted hydrocarbon reservoirs is one of the most promising options for reducing the atmospheric CO2 emissions. The process in geological CO2 sequestration involves injection of supercritical CO2 (scCO2) into porous media saturated with pore water and initiates CO2 flooding with immiscible displacement. The CO2 migration and distribution, and, consequently, the displacement efficiency is governed by the interaction of fluids. Especially, the viscous force and capillary force are controlled by geological formation conditions and injection conditions. This study aimed to estimate the effects of surfactant on interfacial tension between the immiscible fluids, scCO2 and porewater, under high pressure and high temperature conditions by using a pair of proxy fluids under standard conditions through pendant drop method. It also aimed to observe migration and distribution patterns of the immiscible fluids and estimate the effects of surfactant concentrations on the displacement efficiency of scCO2. Micromodel experiments were conducted by applying n-hexane and deionized water as proxy fluids for scCO2 and porewater. In order to quantitatively analyze the immiscible displacement phenomena by n-hexane injection in pore network, the images of migration and distribution pattern of the two fluids are acquired through a imaging system. The experimental results revealed that the addition of surfactants sharply reduces the interfacial tension between hexane and deionized water at low concentrations and approaches a constant value as the concentration increases. Also it was found that, by directly affecting the flow path of the flooding fluid at the pore scale in the porous medium, the surfactant showed the identical effect on the displacement efficiency of n-hexane at equilibrium state. The experimental observation results could provide important fundamental information on immiscible displacement of fluids in porous media and suggest the potential to improve the displacement efficiency of scCO2 by using surfactants.

Global Ocean Data Assimilation and Prediction System in KMA: Description and Assessment (기상청 전지구 해양자료동화시스템(GODAPS): 개요 및 검증)

  • Chang, Pil-Hun;Hwang, Seung-On;Choo, Sung-Ho;Lee, Johan;Lee, Sang-Min;Boo, Kyung-On
    • Atmosphere
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    • v.31 no.2
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    • pp.229-240
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    • 2021
  • The Global Ocean Data Assimilation and Prediction System (GODAPS) in operation at the KMA (Korea Meteorological Administration) is introduced. GODAPS consists of ocean model, ice model, and 3-d variational ocean data assimilation system. GODAPS assimilates conventional and satellite observations for sea surface temperature and height, observations of sea-ice concentration, as well as temperature and salinity profiles for the ocean using a 24-hour data assimilation window. It finally produces ocean analysis fields with a resolution of 0.25 ORCA (tripolar) grid and 75-layer in depth. This analysis is used for providing a boundary condition for the atmospheric model of the KMA Global Seasonal Forecasting System version 5 (GloSea5) in addition to monitoring on the global ocean and ice. For the purpose of evaluating the quality of ocean analysis produced by GODAPS, a one-year data assimilation experiment was performed. Assimilation of global observing system in GODAPS results in producing improved analysis and forecast fields with reduced error in terms of RMSE of innovation and analysis increment. In addition, comparison with an unassimilated experiment shows a mostly positive impact, especially over the region with large oceanic variability.