• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.418-423
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• 1999

This study was performed to find an efficient method to overcome extremely high temperature within greehhouse in summer season. The actual states of practical use for greenhouse in hot summer season were investigated. About 21.6% of the investigated greenhouse farms were no cultivation, and most greenhouse farms were cultivating under the very inferior environment . To examine thermal enviornment of greenhouse according to cooling or assistant cooling , greenhouses were treated with natural ventilation, shading, roof sprinkling , and evaporative cooling with air cool fan. Shading and operating air col fan showed a drop in temperature of 3.8∼4.2$^{\circ}C$ as compared with natural ventilation, and most greenhouse air temperatures were maintained below 35$^{\circ}C$.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.2
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• pp.147-153
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• 2021

Collagen hydrolysate (CH) is known to prevent skin aging by stimulating skin dermal fibroblasts to promote synthesis of extracellular matrix such as collagen and elastin. Recently, among the various factors that cause skin aging, advanced glycation end products (AGEs) have received particular attention. However, the effect of CH on AGE accumulation has not been studied. Since CH could affect AGE accumulation by promoting production of skin structural proteins, clinical trial was performed using low molecule collagen peptide (LMCP), which were CH containing 25% tripeptide and 4% Gly-Pro-Hyp. Skin autofluorescence (SAF) values were measured using an AGE reader to evaluate accumulation of AGE in skin. As a result of applying 0.5% and 1.0% LMCP solutions to the subject's forearm for 8 weeks, the SAF value at the test site significantly decreased compared to the control site. Additionally, in vitro test was performed using CCD-986sk to evaluate the promotion of collagen synthesis in skin fibroblasts by LMCP. As a result, 800 ㎍/mL of LMCP significantly increased synthesis of human pro-collagen Iα1 (COL1A1) in CCD-986sk. Through this study, we have confirmed that tropical LMCP applications can promote collagen synthesis to help anti-glycation effects, suggesting that LMCP has potential as an anti-aging cosmetic material.

• Archives of Pharmacal Research
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• v.24 no.5
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• pp.441-445
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• 2001

Resveratrol, a trihydroxystilbene found in grapes and several plants, has been shown to be active in inhibiting multistage carcinogenic process. Using resveratrol as the prototype, we synthesized several analogs and evaluated their growth inhibitory effect using cultured human cancer cells. In the present report we show that one of the resveratrol analogs, 3, 5,2',4'-tetramethoxy-trans-stilbene, potentiated the inhibition of cancer cell growth. Prompted by the strong growth Inhibitory activity of the compound ($IC_{50}$; $0.8{\mu}$ g/ml) compared to resveratrol ($IC_{50}$; $18{\mu}$ug/ml) in cultured human colon cancer cells (Col2), we performed an action mechanism study using the compound. The compound induced the accumulation of cellular DNA contents in the sub-CO phase DNA contents of the cell cycle by in a time-dependent manner. The morphological changes were also consistent with an apoptotic process. This result indicated that the compound induced apoptosis of cancer cells, and may be a candidate for use in the development of potential cancer chemotherapeutic or cancer chemopreventive agents.

• The Korean Journal of Zoology
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• v.37 no.2
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• pp.232-239
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• 1994

RecA protein plans a central role in homologous recombination and DNA repair in Escherichia cofi (E. colD. The function 8nd structure of this protein are universal in prokarvotes and also conserved in eukaryotes such as yeast. The RecA-like protein with 74 lInDa in size has already been identified and purified from a fission yeast Schizosaccharomyces pombe (5. pommel (Lee, 19911. From this study it was revealed that the RecA-like protein of 5. pombe was highly inducible to various DNA damaging agents and inhibitors of nucleotide pool svnthesizins enzymes. The cellular level of the 5. pombe RecA-like protein wi,u markedly increased, upto 5- to 10-fold, by treatment with various DNA-damains agents including ultraviolet (UV) light, methyl methanesulfonate WS),4-nitroquinoline-1-oxide (4-NQO), and mitomycin-C (MMC), similar to E. cofi RecA protein. Interestingly, the protein level was also increased by inhibitors of nucleotide pool forming enzlwnes such as methotrexate (MTX) and hvdroxvurea (HU). The most effective doses for the inducibility of 4-NQO, MMS, W, MMC, MTX, and HU were 0.2 Ug/ml, 30 mM, 200 J/ma, 0.4 $\mus/ml,$ 1 Ug/ml, and 100 mM, respectively. The range of effective duration time for the inducibilitv of RecA-like protein was from 270 to 450 mins. These results suggest that the 5. pombe RecA-like protein also platys an imortant role in cellular responses to DNA damage as in E. coli system.

• Journal of Nutrition and Health
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• v.55 no.6
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• pp.617-629
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• 2022

Purpose: Osteoporosis is characterized by structural deterioration of the bone tissue because of the loss of osteoblastic activity or the increase in osteoclastic activity, resulting in bone fragility and an increased risk of fractures. Hederagenin (Hed) is a pentacyclic triterpenoid saponin isolated from Dipsaci Radix, the dried root of Dipsacus asper Wall. Dipsaci Radix has been used in Korean herbal medicine to treat bone fractures. In this study, we attempted to demonstrate the potential anti-osteoporotic effect of Hed by examining its effect on osteoblast differentiation in MC3T3-E1 cells. Methods: Osteoblastic MC3T3-E1 cells were cultured in 0, 1, and 10 ㎍/mL Hed for 3 and 7 days. The activity of alkaline phosphatase (ALP), bone nodule formation and level of expression of bone-related genes and proteins were measured in MC3T3-E1 cells exposed to Hed. The western blot test was used to detect the activation of the bone morphogenetic protein-2 (BMP2)/ Suppressor of Mothers against Decapentaplegic (SMAD)1 pathway. Results: Hed significantly increased the proliferation of MC3T3-E1 cells. Intracellular ALP activity was significantly increased in the 1 ㎍/mL Hed-treated group. Hed significantly increased the concentration of calcified nodules. Furthermore, Hed significantly upregulated the expression of genes and proteins associated with osteoblast proliferation and differentiation, such as Runt-related transcription factor 2 (Runx2), ALP, osteopontin (OPN), and type I procollagen (ProCOL1). Induction of osteoblast differentiation by Hed was associated with increased BMP2. In addition, Hed induced osteoblast differentiation by increasing the activity of SMAD1/5/8. These results suggest that Hed has the potential to prevent osteoporosis by promoting osteoblastogenesis in osteoblastic MC3T3-E1 cells via the modulation of the BMP2/SMAD1 pathway. Conclusion: The results presented in this study indicate that Hed isolated from Dipsaci Radix has the potential to be developed as a healthcare food and functional material possessing anti-osteoporosis effects.

• Journal of Sensor Science and Technology
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• v.7 no.1
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• pp.1-8
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• 1998

We have simulated the operating characteristics of the magnetotransistor(MAGFET) by the finite element method and suggested the optimum design conditions to get a maximum sensitivity, The magnetotransistor has been fabricated by CMOS standard processing according to the suggested design conditions and investigated its electromagnetic characteristics. The sensitivity of the magnetotransistor depends on the ratio of width(W) to length(L) of active area rather than its size, and has a maximum when W/L = 1. The relative sensitivity of a fabricated magnetotransistor was 2.53 %/T.

• Journal of the Korean Society for Library and Information Science
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• v.6
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• pp.105-135
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• 1979

This paper is intended to analyze and investigate the versity libraries in Korea. Nineteen national col-present status of four-year national college and unileges and universities based on a number of faculty member, enrollment, department, library staff, volumes in library, academic journals, book budget and facilities of library, and so we have to improve and develop a kind of problems with which national college and university libraries are confronted as follows: 1) Establishment of a position for the INFORMATION SPECIALIST. 2) Reorganization of the organization of college and university library. 3) Securing a position for the EDUCATIONAL RESEARCHER. 4) Upgrading a part of temporary employees. 5) Securing a self-control of library's administration. 6) Revising rules for labor employees in library. 7) Revising a STANDARD STATEMENT FOR ESTABLISHMENT OF UNIVERSITY. (Books and academic journals) 8) ' ( Facilities of library ) 9) Increase of a budget of library and establishing for an article of library budget. 10) Establishment of a new department exclusively responsible for library administration in the Ministry of Education. 11) Giving a leading(proper) role to Seoul National University Library among the other college and university libraries. 12) Establishment of The master course of INFORMATION SCIENCE or THE RESEARCH CENTER FOR INFORMATION SCIENCE in Seoul National University.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.249-256
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• 1983

The aspect of flowering was investigated in 'Georgia' cut lilies which had four flowers per stem. Concurrently effects of preservative solutions on longevity, petal length, water uptake and fresh weight of cut flowers were examined. 1. Days of opening of the 1st, 2nd and 3rd flower were 1-2 days, 3-4 days and 5-6days after beginning of holding treatment respectively. But the 4th flower was opened 9-10 days after beginning of holding treatment when the 1st and 2nd flowers were wilting or drying. 2. The later the opening of flower in a stem was, the shorter the longevity of flower became. But the effects of preservative solutions on longevity were gradually increased as the opening of flower was late in a stem. 3. Preservative solutions containing sucrose and $AgNO_3$ or HQ were able to increase petal length and longevity of the 3rd and 4th flowers sufficiently like the 1st and 2nd flowers. 4. Petal length, water uptake, fresh weight and longevity of cut lilies held in preservative solution containing sucrose, $AgNO_3$ and HQ were increased significantly compared with others. Solution containing sucrose alone increased longevity but decreased water uptake remarkably and did not increase fresh weight and petal length effectively compared with the control.

• Journal of the Korean Institute of Navigation
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• v.17 no.2
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• pp.29-56
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• 1993

The International Convention for the Prevention of Pollution from Ship, 1973, as modified by the Proto-col of 1978 relating thereto, well known as MARPOL 73/78, is probably the most important international agreement on the subject of marine pollution. The main purpose of the Convention is to reduce the total oil remaining on board vessel to minimum. MARPOL is a combination of different sets of rules on oil, chemicals, noxious substances in package forms, sewage and garbage as shown on each Annex. Since the Convention has globally set forth in 1973, it has amended so often whenever reasonable articles are requi-red by contracting states under guidelines of IMO. The amendments, for instance, have continuously perfo-rmed more than 8 times regarding articles, protocols, and five annexes because the original text was badly drafted as the control measures were expressed in general way. This paper, therefore, is intend to summa-rize a main point relating to each amendment, so that persons who have an interest in the Convention would be completely understand for practical implementation. Especially, for legislative purpose or annen-dement of domestic law, it could timely be contributable if specific consolidation and unified interpretations are followed with this paper. Consequently it is much more worth to study for preventing marine pollution from ship with tracing every moment whenever the Convention formally adopted through amending up-to-data.

• Natural Product Sciences
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• v.8 no.4
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• pp.165-169
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• 2002

One-hundred and twenty plant extracts were prepared from 29 Indonesian plants and were primarily tested in vitro cytotoxicity in cultured human lung (A549), colon (Col2), and stomach (SNU-638) cancer cells. As a result, the 23 extracts were found to be active in the criteria of $ED_{50}$<$20\;{\mu}g/ml$. Remarkable cytotoxicity was observed for chloroform and n-butanol extracts of Calotropis gigantea, with $ED_{50}$ values ranging from 0.25 to $0.46\;{\mu}g/ml$. Five extracts derived from Eclipta alba and Excoecaria cochinchinensis displayed potent cell-line selective cytotoxicity, while the rest of 15 extracts showed modest cytotoxic activity against all of three cancer cells. In addition, the cytotoxic potential of subfractions of Zingiber cassumunar against a panel of human cancer cell lines is presented.