• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.265-269
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• 2004

Prunus mandshurica var. glabra Nakai (Rosaceae) is widely distributed in South Korea and bears a fruit with a bitter and astringent taste. An ethyl acetate-soluble extract of Prunus mandshurica was found to exhibit significant cytotoxicity against human leukemia cell lines. Bioassay-directed fractionation of this extract using an MTT(3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) cell proliferation assay as a monitor led to the isolation of the bioactive compounds. Two compounds, 1 and 2 were subsequently found to mediate cytotoxicity against U937, human monocytic leukemia cells. The 50% growth inhibitory concentrations ($IC_{50}$/) of compounds 1 and 2 on U937 were 40 and 62 $\mu\textrm{g}$/mL, respectively.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.1
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• pp.11-16
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• 2011

When the trains are passed the station, a serious force is applied to ground and the caused vibration is propagated to the area of the station by the ground and rocks. The caused vibration brings about the operation interruption of the equipment which is sensitive to the vibration, or will bring about the structural damage of the station. In this study, to investigate the vibrational evaluation of railway station by the train service, the vibration simulation was performed and analyzed the effect of the vibration isolating countermeasure. From the vibration measurement, all trains that passed through the station exceeded the vibration criteria. Therefore, the vibration isolating countermeasure was established and the vibration simulation was performed.

• Structural Engineering and Mechanics
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• v.40 no.2
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• pp.167-190
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• 2011

In order to upgrade the seismic resistibility of structures and enhance the functionality of an isolator, a new base isolator called the multiple trench friction pendulum system (MTFPS) is proposed in this study. The proposed MTFPS isolator is composed of a trench concave surface and several intermediate sliding plates in two orthogonal directions. Mathematical formulations have been derived to examine the characteristics of the proposed MTFPS isolator possessing numerous intermediate sliding plates. By means of mathematical formulations which have been validated by experimental results of bidirectional ground shaking, it can be inferred that the natural period and damping effect of the MTFPS isolator with several intermediate sliding plates can be altered continually and controllably during earthquakes. Furthermore, results obtained from the component and shaking table tests demonstrate that the proposed isolator provides good protection to structures for prevention of damage from strong earthquakes.

• Journal of Ginseng Research
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• v.19 no.2
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• pp.122-126
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• 1995

The effects of treating bovine heart mitochondria with potassium chloride and surfactants such as digitonin and n-dodecy-$\beta$-maltoside (DMS) including plant saponins on extracting cytochrome c were examined. The spectra given by the cytochrome c-containing solutions from the extraction were inspected to ascertain whether ginseng and bellflower saponins could be used instead of the generally- employed surfactants of digitonin and DMS. These studies implied that the effect of ginseng saponins is superior to that of digitonin but inferior to that of DMS, and give rise to the idea of substitutional property of ginseng saponins for the widely-employed surfactants in the extraction of mitochondria intermembrane cytochrome c. The substitution for the solubilizing surfactants by bellflower saponins could, however, not presumably be anticipated; while ginseng saponin mixture are a suitable substitute.

• Archives of Pharmacal Research
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• v.27 no.7
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• pp.730-733
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• 2004

Bioassay-guided fractionation has led to the isolation of triterpenoid saponins such as Acutoside A (3-O-[O-${\beta}$-D-glucopyrano$yl-(1${\to}$2)-O-${\beta}$-D-glucopyranosyl] oleanolic acid) from the whole plants of Viola hondoensis. Among them, Saponin 1 exhibited potent inhibitory activity against matrix metalloproteinase (MMP)-1, and prevented the UV-induced changes in the MMP-1 expression. In addition, compound was isolated from this plant for the first time.

• Archives of Pharmacal Research
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• v.23 no.3
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• pp.237-239
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• 2000

The antioxidant activity of Artemisia montana was determined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and inhibitory activity against free radical generation of hepatocytes ($AC_2$F). The methanol extract of A. montana showed strong radical scavenging activity at a concentration of $10.1{\mu}g/m{\ell}$, and thus fractionated by solvent extraction. Esculetin and luteolin 7-O-rutinoside (scolymoside) were isolated as the active principles from the EtOAc and interphase fractions, respectively. The antioxidant activity of these compounds were comparable to that of L-ascorbic acid.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.98-100
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• 2012

컴퓨팅 성능향상과 장비의 증가는 전력소비의 증가로 이어져 데이터센터 경영자에게 운영경비의 증가로 피할 수 없는 중요한 문제가 되었다. 그래서 미국의 데이터센터에서는 에너지 효율화 지수인 PUE(Power Usage Effectiveness)를 표준지수로 정하고 에너지소비를 관리하고 있다. 데이터센터에서 소비되는 에너지에서 IT부문과 비IT부문의 에너지 소비비율은 50:50 비율이다. IT장비는 처음 도입 시 에너지 효율적인 장비를 도입하면 컴퓨터 운영상에서 에너지를 절감할 기회는 많지가 않지만, 비IT부문은 설비운영적인 측면으로 안정성을 고려하면서 동시에 효율적인 운영환경을 유지하는 것이 가능하다. 본 문서에서는 비IT부문에서 전산실 장비의 열복도-냉복도 분리 배치가 에너지 절감효과가 어느 정도인지 실험을 하였으며, 그 실험결과를 기술하였다.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.260.1-260.1
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• 2003

Magnoliae Flos(‘shin-j’). the flower buds of Magnolia kobus, is acrid to taste with a ‘warm’ property. It is a ‘wind-cold’ discutient and nasal decongestant and is principally used in the treatment of nasal congestion with headache, sinusitis and allergic rhinitis. By screening inhibitory activities on the melanin polymer biosysthesis in B-16 mouse melanoma cell lines, methylene chloride extract of Magnoliae Flos was found to have inhibitory effect on melanin polymer biosynthesis. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.201.1-201.1
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• 2003

Study of Acyl-CoA:cholesterol acyltransferase (ACAT) inhibitors from medicinal plants, we found strong inhibitory activity of ACAT enzyme from rat liver microsome by the CHC1$_3$ extract of Piper longum. Bioactivity-guided fractionation led to the isolation of Guineensine (1), its structure was elucidated by spectroscopic (IR, UV, MS and NMR) means. It inhibited ACAT activity in a dose-dependent manner with IC$\sub$50/ values of 1.2 $\mu\textrm{g}$/ml on in vitro assay using rat liver microsome.

• Ocean and Polar Research
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• v.34 no.4
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• pp.385-394
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• 2012

In this study, crude extracts of the marine eelgrass Zostera japonica and their solvent-partitioned fractions were evaluated for their inhibitory effect against AGS, HT-1080 and MCF-7 human cancer cells using MTT assay. Each of the crude extracts (acetone/methylene, chloride, and methanol) of Z. japonica showed a significant inhibitory effect on the growth of human cancer cells. The combined crude extracts were partitioned between $CH_2Cl_2$ and water. The organic layer was further partitioned between 85% aq. MeOH and n-hexane, and the aqueous layer was then fractionated into n-BuOH and $H_2O$, successively. Growth inhibition effects of solvent-partitioned fractions from Z. japonica on human cancer cells increased in a dose-dependent manner. Among these tested samples, the 85% aq. MeOH fraction revealed good inhibitory effects on the growth of AGS and HT-1080 human cancer cells, while the n-hexane fraction exhibited good inhibitory effects on the growth of AGS and MCF-7 human cancer cells. In addition, 85% aq. MeOH and n-hexane fractions enhanced mRNA expression of p53 gene. These results suggest that there is further scope for the isolation of active compounds from Z. japonica, which should show much stronger anticancer activity.