http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이희석,이태희,이동희,윤범식,이기원,김진수,구영태,김준호 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.12
A number of studies employing different in vitro assays have demonstrated the estrogen-like activity of natural substances. All assays have their advantages and limitations as a screening tool. No single in vitro assay is considered ideal for predicting estrogenic action in a complex in vivo system. To assess agonistic activities of several medicinal herbs on the estrogen receptor (ER) and their metabolic alteration, the Organization for Economic Cooperation and Development (OECD) Performance-Based Test Guideline No. 455 in vitro assay was performed in this study using recombinant VM7Luc4E2 cells in combination with rat liver S9 fractions. Ethanol extracts of medicinal herbs showed binding affinities for ER-α and ER-β at different levels. However, luciferase reporter assay using VM7Luc4E2 cells revealed that only two test extracts [Pueraria lobata root extract (PLE); Glycyrrhiza glabra root extract (GGE)] exhibited ER transcriptional activity when their activities were compared with the response by 17β-estradiol. Importantly, incubation of PLE or GGE with rat liver S9 fractions increased their ER transcriptional activities, in particular when phase I metabolic enzymes were activated. Puerarin and glabridin were the most abundant isoflavones found in PLE and GGE, respectively. The present results demonstrate that PLE and GGE possess potential as ER agonists with their metabolic activation. This study also suggests that the application of OECD in vitro assay with rat liver S9 fraction is an efficient screening tool to evaluate estrogenic activities of natural substances.
Development of sulfuric acid resistant concrete sewer pipes using waste glass powder and meta-kaolin
이희석,소광호 한양대학교 세라믹연구소 2018 Journal of Ceramic Processing Research Vol.19 No.2
Performance deterioration of concrete has recently been recognized as a significant problem, and is mainly due to corrosionand crack formation, leading to reduced load carrying capacity of reinforced concrete structures. Particularly, the durabilityof concrete structures built in seawater, groundwater, and waste water treatment facilities are significantly reduced whensubjected to chemical erosion by acid and sulfate, and require countermeasures to increase their lifespans. Thus, this study wasconducted to evaluate the performance of sulfate-resistant concrete treated with metakaolin and waste glass powder as abinder to improve sulfate and chemical resistance performance for the development of sulfate-resistant sewer pipes. Concretesewer pipes were successfully developed with excellent sulfate resistance and high strength of 50 MPa or higher.
턴키 대상공사 선정을 위한 시범사업 도입방안에 관한 연구
이희석,차준엽,백준홍 대한건축학회 1999 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.19 No.2
After the countermeasure for the activity of the turnkey contract was announced by the Korean government, the turn-key contract has being increased in domestic construction industry. But it is defective to perform a turn-key contract in the technical and political aspects. Even though there are many merits at a turn-key contract, nowadays, the turn-key contract makes the point at issue in Korea by such aspects. Among the point at Issue, the selection of improper abject for the turn-key contract becomes the most serious defect caused by a non-objective and an unsuitable criterion. So, in this research, it is suggested that pilot projects be adopted and put through to get the materials and criteria to properly selecting the turn-key project. At the same time, the adoptive plan for domestic construction industry is suggested for the efficient performance of the pilot projects by introducing and analyzing the cases of the other countries.