• Title/Summary/Keyword: 연구문제

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Skin Permeability of Petroselinum Crispum Extract Using Polymer Micelles and Epidermal Penetration Peptide (고분자 미셀과 경피투과 펩티드를 이용한 파슬리 추출물의 피부흡수 효과)

  • An, Gyu Min;Park, Su In;Kim, Min Gi;Heo, Soo Hyeon;Shin, Moon Sam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.3
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    • pp.265-275
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    • 2019
  • This study was conducted to investigate physiological activity and its skin permeability of Petroselinum crispum extract using polymer micelles and cell penetrating peptide. In the antioxidant test, the total concentrations of polyphenol compounds were determined to be $121.68{\pm}2.49mg/g$ (for ethanol extract and), $72.42{\pm}1.52mg/g$ (for hydrothermal extract.). The DPPH radical scavenging ability was $90.48{\pm}0.46%$ (for ethanol extract) and $83.92{\pm}0.13%$ (for hydrothermal extract) at 2000 mg/L. ABTS radical scavenging ability was $91.08{\pm}0.14%$ for ethanol extract ethanol extract, which is higher than that of hydrothermal extract at 800 mg/L ($69.63{\pm}0.55%$). In the SOD experiments, the P. crispum ethanol extract showed higher SOD activity than that of the P. crispum hydrothermal extract at all concentrations.. At a concentration of 16,000 mg/L, P. crispum ethanol extract showed the highest SOD activity of $128.45{\pm}0.70%$. The elastase inhibitory assay also showed concentration dependence and elastase inhibition of P. crispum ethanol extract was $99.99{\pm}1.54%$, which was the highest at 2,000 mg/L. To solve the problem of insolubility and to improve skin permeability of the extract, PCL-PEG polymer micelle containing P. crispum ethanol extracts and 1% cell permeable peptide, hexa-D-arginine (R6) were successfully prepared with a particle size of 40.10 nm. In the results of 24 hours of skin permeation experiment, total accumulated beta-carotene amounts showed $37.99{\mu}g/cm^2$ in Petroselinum crispum extracts and $68.38{\mu}g/cm^2$ (1.8 times) in P. crispum extract of the particles.

History and Future Direction for the Development of Rice Growth Models in Korea (벼 작물생육모형 국내 도입 활용과 앞으로의 연구 방향)

  • Kim, Junhwan;Sang, Wangyu;Shin, Pyeong;Baek, Jaekyeong;Cho, Chongil;Seo, Myungchul
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.21 no.3
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    • pp.167-174
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    • 2019
  • A process-oriented crop growth model can simulate the biophysical process of rice under diverse environmental and management conditions, which would make it more versatile than an empirical crop model. In the present study, we examined chronology and background of the development of the rice growth models in Korea, which would provide insights on the needs for improvement of the models. The rice crop growth models were introduced in Korea in the late 80s. Until 2000s, these crop models have been used to simulate the yield in a specific area in Korea. Since then, improvement of crop growth models has been made to take into account biological characteristics of rice growth and development in more detail. Still, the use of the crop growth models has been limited to the assessment of climate change impact on crop production. Efforts have been made to apply the crop growth model, e.g., the CERES-Rice model, to develop decision support system for crop management at a farm level. However, the decision support system based on a crop growth model was attractive to a small number of stakeholders most likely due to scarcity of on-site weather data and reliable parameter sets for cultivars grown in Korea. The wide use of the crop growth models would be facilitated by approaches to extend spatial availability of reliable weather data, which could be either measured on-site or estimates using spatial interpolation. New approaches for calibration of cultivar parameters for new cultivars would also help lower hurdles to crop growth models.

Physiological Activity of Robinia pseudo acacia Leaf Extracts and Enhancement of Skin Permeation Using Polymer Micelles and Cell Penetrating Peptide (아카시아 잎 추출물의 생리 활성 및 고분자 미셀과 세포투과 펩티드를 적용한 피부흡수증진 효과)

  • Heo, Soo Hyeon;Park, Su In;An, Gyu Min;Shin, Moon Sam
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.3
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    • pp.271-282
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    • 2019
  • This study was conducted to evaluate physiological activity of Robinia pseudo-acacia leaf and its skin penetration using polymer micelles and skin penetrating peptide. After extraction with Robinia pseudo-acacia using the ethanol and distilled water, various physiological activities were examined. The total concentration of polyphenol compounds was determined to be 47.42 mg/g (ethanol extract), 56.88 mg/g (hydrothermal extract) and DPPH radical scavenging ability at $1,000{\mu}g/mL$ was 44.24% in ethanol extract and it is higher than value(41.50%) in hydrothermal extract. The elastase inhibitory assay showed concentration dependence and elastase inhibition of Robinia pseudo acacia leaf ethanol extract was 54.09%, which was the highest at $500{\mu}g/mL$. In the SOD-like experiments, the concentration-dependent results were showed and the SOD-like activity of the Robinia pseudo-acacia leaf ethanol extract was higher than that of the Robinia pseudo acacia leaf hydrothermal extract at all concentrations. At a concentration of $500{\mu}g/mL$, Robinia pseudo acacia leaf ethanol extract showed the highest SOD-like activity of 76.41%. The tyrosinase inhibition at $20{\mu}g/mL$ was determined to be 56.47% (ethanol extract), 23.05% (hydrothermal extract). In the antimicrobial experiments, the hydrothermal extract had no effect, but ethanol extract represented maximum clear zone of 11.00 mm in Propionbacterium acnes strain and maximum clear zone of 10.50 mm. in Bacillus subtilis strain. To solve the problem of insolubility and to improve skin penetration, PCL-PEG polymer micelles containing Robinia pseudo-acacia leaf ethanol extracts and 1.0% cell permeable peptide, hexa-D-arginine (R6) were successfully prepared with particle size of 108.23 and 126.47 nm and excellent skin permeation effects could be showed.

Inhibitory Effects of Locusta migratoria Ethanol Extracts on RANKL-induced Osteoclast Differentiation (RANKL 유도된 파골세포 분화에 대한 풀무치 에탄올 추출물의 분화 억제 효과)

  • Baek, Minhee;Seo, Minchul;Lee, Joon Ha;Lee, Hwa Jeong;Kim, In-Woo;Kim, Sun Young;Kim, Mi-Ae;Kim, Sunghyun;Hwang, Jae-Sam
    • Journal of Life Science
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    • v.29 no.10
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    • pp.1104-1110
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    • 2019
  • Recently, there has been an increase in the elderly population of the world. Consequently, bone metabolic diseases such as osteoporosis are emerging as a social problem. Osteoclasts play a role in bone resorption, and osteoporosis is induced when bone resorption occurs excessively. Because currently used bone resorption inhibitors may cause side effects when used for a long period of time, it is necessary to develop a new material that effectively inhibits osteoclast differentiation. This study aimed to confirm the inhibitory effect of ethanol extract of Locusta migratoria on RANKL-induced osteoclast differentiation and its mechanism. The toxicity and proliferation effects of LME on RAW264.7 osteoclasts were measured by an MTS assay. There was no cytotoxicity or proliferation when the osteoclasts were treated with up to $2,000{\mu}g/ml$ of LME. In order to confirm the effect of LME on the differentiation of osteoclasts, osteoclasts were treated with RANKL alone or with LME for 3 days. As a result of a TRAP (tartrate-resistant acid phosphatase) assay, the increasing osteoclast differentiation by RANKL decreased in a concentration-dependent manner with the treatment of LME. In addition, LME suppressed the expression of differentiation-related marker genes (TRAP, RANK, NFATc1, and CK) and proteins (NFATc1 and c-Src) that had been increased by RANKL. Also, LME influenced the $NF-{\kappa}B$, ERK and JNK signaling pathways, resulting in the inhibition of osteoclast differentiation. These results suggest that LME may be used as a novel functional material for the prevention and treatment of osteoporosis by playing a role in inhibiting bone absorption.

Spatiotemporal and Longitudinal Variability of Hydro-meteorology, Basic Water Quality and Dominant Algal Assemblages in the Eight Weir Pools of Regulated River(Nakdong) (낙동강 8개 보에서 기상수문·기초수질 및 우점조류의 시공간 종적 변동성)

  • Shin, Jae-Ki;Park, Yongeun
    • Korean Journal of Ecology and Environment
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    • v.51 no.4
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    • pp.268-286
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    • 2018
  • The eutrophication and algal blooms by harmful cyanobacteria (CyanoHAs) and freshwater redtide (FRT) that severely experiencing in typical regulated weir system of the Nakdong River are one of the most rapidly expanding water quality problems in Korea and worldwide. To compare with the factors of rainfall, hydrology, and dominant algae, this study explored spatiotemporal variability of the major water environmental factors by weekly intervals in eight weir pools of the Nakdong River from January 2013 to July 2017. There was a distinct difference in rainfall distribution between upstream and downstream regions. Outflow discharge using small-scale hydropower generation, overflow and fish-ways accounted for 37.4%, 60.1% and 2.5%, respectively. Excluding the flood season, the outflow was mainly due to the hydropower release through year-round. These have been associated with the drawdown of water level, water exchange rate, and the significant impact on change of dominant algae. The mean concentration (maximum value) of chlorophyll-a was $17.6mg\;m^{-3}$ ($98.2mg\;m^{-3}$) in the SAJ~GAJ and $29.6mg\;m^{-3}$ ($193.6mg\;m^{-3}$) in the DAS~HAA weir pools reaches, respectively. It has increased significantly in the downstream part where the influence of treated wastewater effluents (TWEs) is high. Indeed, very high values (>50 or $>100mg\;m^{-3}$) of chlorophyll-a concentration were observed at low flow rates and water levels. Algal assemblages that caused the blooms of CyanoHAs and FRT were the cyanobacteria Microcystis and the diatom Stephanodiscus populations, respectively. In conclusion, appropriate hydrological management practices in terms of each weir pool may need to be developed.

Efficient virus elimination for apple dwarfing rootstock M.9 and M.26 via thermotherapy, ribavirin and apical meristem culture (사과 왜성대목 M.9 및 M.26의 고온, ribavirin, 생장점 배양을 통한 바이러스 제거)

  • Kwon, Young Hee;Lee, Joung Kwan;Kim, Hee Kyu;Kim, Kyung Ok;Park, Jae Seong;Huh, Yoon Sun;Park, Eui Kwang;Yoon, Yeo Joong
    • Journal of Plant Biotechnology
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    • v.46 no.3
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    • pp.228-235
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    • 2019
  • Apple (Malus pumila) is one of the most economically important fruits in Korea. but virus infection has decreased the sustainable production of apples and caused serious problems such as yield loss and poor fruit quality. Virus or viroid infection including apple chlorotic leaf spot virus (ACLSV), apple stem pitting virus (ASPV), apple stem grooving virus (ASGV), apple mosaic virus (ApMV) and apple scar skin viroid (ASSVd) have been also reported in Korea. In many cases, as apple gets infected with virus and viroid with no specific symptoms, the damage and symptoms caused by the viruses are not detected. In our research, viruses in the rootstock were eliminated for a virus-free apple dwarfing rootstock of M.9 and M.26. The virus elimination methods were apical meristem culture, thermotherapy ($37^{\circ}C$, 6 weeks) and chemotherapy($Ribavirin^{(R)}$). The detection of apple viruses was accomplished by Enzyme-linked Immuno-Sorbent Assay (ELlSA) and reverse transcription-polymerase chain reaction (RT-PCR). RT- PCR method was 10 ~ 30% more sensitive than the ELISA method. The efficiency of virus elimination was enhanced in apical meristem culture method. The acquisition rate of virus-free apple dwarfing rootstocks was 30 ~ 40% higher in apical meristem culture. After the meristem culturing of M.9, the infection ratio of ACLSV, ASPV and ASGV was 45%, 60% and 50%, respectively. In the apple dwarfing rootstock of M.26, the infection ratio of ACLSV, ASPV and ASGV was 40%, 55% and 55%, respectively. Based on this study, the best method for the production of virus-free apple dwarfing rootstocks was the apical meristem culture.

A Study on changes in Hitting-pressing forms of flat plate in Gyeongju area -Short beating, Medium beating plate, long beating plate and Stamped-roof tile- (경주지역 평기와의 타날형태 변화에 대한 검토 -단판·중판·인장 그리고 장판으로-)

  • Cha, Soon-chul
    • Korean Journal of Heritage: History & Science
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    • v.40
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    • pp.73-104
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    • 2007
  • Centering around ruins recognized of being relatively early stage related to flat tile and brick, excavated in Silla capital area, the study attempted elementary approach to seek the appearance time of every remain through comparing them from the excavated cases and production methods of Short beating, Medium beating plate, Long beating plate and Stamped-roof tile. Gyeongju began to use the short beating plate made of tile-less plates or tile plate and increased its quantity. That is deemed to be due to efficiency of beating plate making methods, and moreover to be limited only for use in the palace castle and offices. That is, making short beating plates is presumed to be made merely under some definite objectives. Medium beating plate has been spread to the whole country since Silla and Baekje united. Differently from Koguryo and Baekje, Silla had its unique Beating-plates making technology available for mass-production, which was spread to the whole country and resulted in disappearing of Koguryo and Baekje technology. Long beating plate was not nearly founded in Gyeongju area, but flat tile and common tile excavated in Sachunwang Temple site and Samrang Temple 3rd remains are known. In the outskirts of Gyeongju, long beating plate appeared between the latter half of 8C and the beginning of 9C. Until now, different views have raised to appearance of long beating plate of Unified Silla, which is expected to be clarified under the situation excavated by position relations. Stamped-roof title in Gyeongju is estimated as used after the datum point year 679. While in Baekje area, five stems and branches were involved, in Silla area, code or sign was shown much. The difference between two areas would be due to each other factory, and especially the marked contents werenot letters, which means it had been changed from Baekje s existing-methods. That is, it says the production environment changed owing to Silla's merging. And stamped-roof tile was temporarily used in Gyeongju but soon disappeared, which was because Silla beating plates made under cylinder-shaped tile barrel(圓筒瓦桶) and hitting-pressing of Medium beating plate had beenspread to the whole country, so the production technology of Koguryo and Baekje was naturally dismissed. In consequence, the mergence by Silla brought about unification of each nation's special technology.

A Study on a Paradigm Shift to Archives of everyday life (일상 아카이브(Archives of everyday life)로의 패러다임 전환을 위한 소론)

  • Kwak, Kun-Hong
    • The Korean Journal of Archival Studies
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    • no.29
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    • pp.3-33
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    • 2011
  • No one can deny the harsh reality that archival culture has not yet been permeated extensively into all the spheres of our society. Only fragmented records in fixed areas are in the custody of archives. Records to build a living memory for the history of our present are hard to find or remain minimal, if anywhere. Above all, there are few records in archives concerned with the everyday life of common people. No consideration has not been made about the reason for being of archives, not to mention of the strategy for establishing the archival culture. Accordingly, a paradigm shift is required for archives directly connected with the everyday life of common people. Archives of everyday life means one which interprets the behaviour and experiences of individuals(groups) within the context of society through categorizing everyday life of common people into the lesser fields. And archives of everyday life also means an organization or facility/place which documents the everyday life of individuals(groups), and collect, appraise, select and preserve the records from the view point of humanities for the reconstruction of history from the bottom. Archives of everyday life is an attempt to reconstruct memory and records on behaviour by and torment of the common people in the modern history of Korea, on the basis of which we can seek out the oppressive structure in the daily life of capitalism. Archival community should discuss about what is the meaning of records in the age of democracy unlike that of authoritarian era. We also need to have definite direction on the what kinds of records are to be created and appraised from the standpoint of common people. We are to make it possible to create Zeitgeist in the tackle of records and archives' content. on this kind of attempt archival community could make a practical contribution forward a more advanced democracy, resulted in having an opportunity to change the essence of archives.

A Study on the Effect of Social Enterprises Characterics on Financial and Social Performance (사회적기업의 특성이 재무적 성과와 사회적 성과에 미치는 영향: CEO 특성을 중심으로)

  • Hwang, Sooo-Young;Kim, Yong-Duck
    • 한국벤처창업학회:학술대회논문집
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    • 2018.11a
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    • pp.165-175
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    • 2018
  • Since the 1997 financial crisis, large scale unemployment and poverty have become serious, and public and social job creation projects have been carried out. However, with the limitations of low-wage and short-term jobs, the need for long-term and high quality jobs gradually began to attract attention. In recent years, social enterprises have grown both quantitatively and qualitatively and interest in social enterprises has increased. And also it is interested in the determinants of success and failure of social enterprises in the academic field. In this study, we examined the effects of social enterprise characteristics on financial and social performance, and we analyzed empirically by using social enterprises registered in the Korea Social Enterprise Agency. The financial performance of the social enterprise is measured by the net income ratio, operating income ratio, and the return on asset. The social performance of the social enterprise is measured by total number of workers and the employment rate of the vulnerable social groups. The characteristics of the social enterprise include the CEO characteristics (gender, age, experience in operating the social enterprise), the firm size, and the elapsed time of the authentication. The results of the empirical analysis are as follows. First, as a result of analysis for the effect on financial performance, we found that the financial performance have a statistically significant positive relationship with firm size, organizational form, government subsidies and capital adequacy ratio. And it is found that the social performance have a statistically significant negative relationship with CEO age, credit debt dependence. Second, as a result of analysis for the effect on social performance, we foumd that total number of workers have a significant positive relationships with CEO gender, CEO age, and firm size, government subsidies, while total number of workers have a significant negative relationship with certification type and industry dummy. On the other hand, the employment rate of the vulnerable social groups have a siginificant positive relationship with CEO gender and certification type and It have not statistically significant relationship with the government subsidies and the firm size.

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Disaster Risk Assessment using QRE Assessment Tool in Disaster Cases in Seoul Metropolitan (서울시 재난 사례 QRE 평가도구를 활용한 재난 위험도 평가)

  • Kim, Yong Moon;Lee, Tae Shik
    • Journal of Korean Society of Disaster and Security
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    • v.12 no.1
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    • pp.11-21
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    • 2019
  • This study assessed the risk of disaster by using QRE(Quick Risk Estimation - UNISDR Roll Model City of Basic Evaluation Tool) tools for three natural disasters and sixteen social disasters managed by the Seoul Metropolitan Government. The criteria for selecting 19 disaster types in Seoul are limited to disasters that occur frequently in the past and cause a lot of damage to people and property if they occur. We also considered disasters that are likely to occur in the future. According to the results of the QRE tools for disaster type in Seoul, the most dangerous type of disaster among the Seoul city disasters was "suicide accident" and "deterioration of air quality". Suicide risk is high and it is not easy to take measures against the economic and psychological problems of suicide. This corresponds to the Risk ratings(Likelihood ranking score & Severity rating) "M6". In contrast, disaster types with low risk during the disaster managed by the city of Seoul were analyzed as flooding, water leakage, and water pollution accidents. In the case of floods, there is a high likelihood of disaster such as localized heavy rains and typhoons. However, the city of Seoul has established a comprehensive plan to reduce floods and water every five years. This aspect is considered to be appropriate for disaster prevention preparedness and relatively low disaster risk was analyzed. This corresponds to the disaster Risk ratings(Likelihood ranking score & Severity rating) "VL1". Finally, the QRE tool provides the city's leaders and disaster managers with a quick reference to the risk of a disaster so that decisions can be made faster. In addition, the risk assessment using the QRE tool has helped many aspects such as systematic evaluation of resilience against the city's safety risks, basic data on future investment plans, and disaster response.