• Computational Structural Engineering
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• v.7 no.2
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• pp.89-99
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• 1994

The nonlinear dynamic behaviors of guardrail established on the local or high way have been investigated using BARRIER VII program with respect to four design variables such as section type of beams and posts, impact angle, impact velocity and vehicle weight. Computer simulation programs are sophisticated analytical models for analyzing dynamic vehicle/barrier interactions and provide a relatively inexpensive alternative to full scale crash testing. This study has been focused on the structural adequacy, occupant risk, and vehicle trajectory. For this purpose, the maximum defection and impact force have been calculated to design the clear zone and to analyze effect of impact attenuation. Also, the acceleration of vehicle and exit angle after collision have been computed to estimate the occupant risk. From this study, it is suggested that we should strengthen the design criteria of guardrail to prevent from disastrous traffic accidents.

• The Korean Journal of Mycology
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• v.39 no.2
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• pp.126-130
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• 2011

In the course of search for multifunctional microbial inoculants, three Bacillus strains (BS11-1,BS11-2,BS11-3) with biological control and biofertilizing effects were selected. In this study, their ability for solubilization of insoluble phosphate, production of indole-3-acetic acid (IAA), siderophore, and hydrolytic enzymes, and antagonism against phytopathogenic fungi were estimated. All strains produced IAA and siderophore depending on culture time and produced a visible clear zone on agar plate containing 0.5% carboxylmethyl cellulose as a carbon source. Also, these strains exhibited antifungal activities against phytopathogenic fungi, Botrytis cinerea, Cylindrocarpon destructans, Fusarium oxysporum, Rhizoctonia solani, and Phytophthora capsici.

• Animal cells and systems
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• v.16 no.2
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• pp.162-171
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• 2012

We investigated food webs of a $Salix$ $subfragilis$-dominated wetland in the Janghang wetland in the Hangang estuary, which is very close to the Demilitarized Zone, along the west coast of Korea. Our study focused on understanding sesarmine crab ($Sesarma$ $dehaani$)-related food webs in a $S.$ $subfragilis$ forest. For our study, we used carbon and nitrogen stable isotopes and fatty acid biomarkers. We collected samples of plants, animals, and detrital sediment from four quadrats ($5{\times}5m^2$) set in the $S.$ $subfragilis$ community. Samples were collected from September 2006 to June 2009, except during the winter hibernation period of $S.$ $dehaani$. In the wet season, the sediment showed relatively high ${\delta}^{13}C$ and low ${\delta}^{15}N$ signatures compared with relatively low ${\delta}13C$ and high ${\delta}15N$ signatures in the dry season. Mature $S.$ $dehaani$ appeared to feed on fresh leaves and other carbon sources, such as immature individuals or fish, in addition to detrital sediment, which appeared to be the main carbon source for immature crabs. Principal component analysis of fatty acid biomarkers of $S.$ $dehaani$ showed a clear difference between immature individuals (10-30 mm) and mature ones (larger than 30 mm), indicating that the main food source for immature crabs was detrital sediment, whereas mature crabs foraged plants in addition to consuming detrital sediment. On the basis of our results from stable isotope and fatty acid analyses, mature $S.$ $dehaani$ appeared to feed on detrital sediment and fresh leaves of $S.$ $subfragilis$ in summer in addition to engaging in cannibalism of immature individuals.

• Journal of Life Science
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• v.20 no.3
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• pp.374-380
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• 2010

The objective of this research was to evaluate the inhibitory activities of phenolic compounds isolated from Cheomoknosang callus on Helicobacter pylori. Total phenolic compounds of 80% ethanol extracts from callus were 15.3 mg/g. The activity of H. pylori inhibition at 80% ethanol extracts from Cheongmoknosang callus was determined as 14 mm clear zone. Isolation of inhibitory compounds was carried out on Sephadex LH-20 and MCI-gel CHP-20 column chromatography using a gradient elution procedure of increasing MeOH in $H_2O$. The chemical structure of the inhibitory compound against Helicobacter pylori was confirmed as protocatechuic acid, chlorogenic acid, caffeic acid and rosemarinic acid by spectroscopic analysis of FAB-MS, NMR and IR spectrum.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.1035-1038
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• 2005

Yacon (Polymnia sonchifolia Poepping & Endlicher), which contains fructo-oligosaccharide, is low calorie functional food. Yacon is efficacious against cholesterol, obesity, and diabetes. Yacon K-23 has antibacterial activity against Gram-positive (Listeria monocytogenes KCTC 3710 and Staphylococcus aureus KCTC 1927) and negative (Salmonella typhimurium KCTC 2514, Escherichia coli KCCM 11591, Proteus vulgaris KCTS 2512, and Pseudomonas aeruginosa KCCM 11803), Yacons A (water extract) and B (crushed juice) showed clear zone of 10mm, while Cassiae Semen, Acanthopanacis Cortex, Angelica gigas showed 7-10mm. Yacon jam showed good sensory attributes, suggesting it could be utilized as food ingredient. Hardness, adhesiveness, and strength of strawberry jam with or without aloe vera were higher than those of yacon jam with or without aloe vera.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.56-62
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• 1989

Antagonistic effects of Streptomyces species aganinst Fusarium solani causing ginseng root rot were investigated in terms of chitinase activity and growth inhibition in vitro. Among 131 isolates of streptomycetes obtained from ginseng cultivating soil, 9 isolates producing large clear zone around the colony on a chitin agar medium were selected for further study. All 9 isolates produced chitinase in a range from 0.10 to 0.38 U lysing cells of F. solani and inhibited germination of the conidia. In the ten-fold condentrated culture filtrate of S. alboniger ST59 and S. roseolilacinus ST129, the number of conidia of F. solane was reduced to about 20% of original count within 14 days. When S. alboniger ST59 and F. solani were grown simultaneously in the mineral saly medium, chitinase activity increased with incubation period, whereas mycelial volume of F. solani decreased. In a chitin added mineral salt medium, chitinase activity increased during the first four days and maintained steady level until the 8th day, and increased thereafter. S. alboniger ST59 lysed mycelia, conidia and even chlamydospores of F. solani. It is probable that the antagonistic activity of this streptomycete against F. solani is the lysis of fungal cell wall by streptomycete producing chitinase affected by antifungal substances.

• The Journal of Korean Medicine
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• v.26 no.1 s.61
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• pp.134-147
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• 2005

Objective: This study was carried out to investigate the effects of Gami-Shengmayuipung-tang on acne. Methods : The effects of Gami-Shengmayuipung-tang (SYTSRG) on acne were measured by the $5\alpha-reductase$ inhibition, the sterilizing power for Propionibactrium acnes, the cytotoxicity of human monocyte, the inhibition for prostaglandins$(PGE_2)$, interleukins $(IL-l\beta)$ and $TNF-\alpha$ in inflammation, and the size of the hamtster ear sebaceous gland related to P. acnes. Results: On the $5\alpha-reductase$ inhibition of SYTSRG in vitro, an undiluted solution of SYTSRG showed $80\%$ inhibition on $5\alpha-reductase$ and 1/10 diluted solution of SYTSRG showed $40\%$ inhibition on $5\alpha-reductase$. On the sterilizing power for Propionibactrium acnes related acne, an undiluted solution and 1/10 diluted solution of SYTSRG formed $12\beta{\AE}$ clear zone diameters. SYTSRG did not show cytotoxicity of human monocyte. Concentrations of $0.01\%\;and\;0.04\%\;and\;0.08\%$ of SYTSRG inhibited the production of prostaglandins $(PGE_2)$ in the human monocyte stimulated with P. acnes LPS. $0.08\%$ and less of SYTSRG inhibited the production of interleukins $(IL-l\beta)$ in the human monocyte stimulated with P. acnes LPS. Concentrations of $0.04\%,\;0.08\%\;and\;0.12\%$ of SYTSRG inhibited the production of $TNF-\alpha$ in the human monocyte stimulated with P. acnes LPS. As the antiandrogenic compound, SYTSRG was used in hamster ears with topical application. SYTSRG diminished the size of the hamster ear sebaceous gland in males, but not in females. Conclusion: The present data suggest that SYTSRG may affect the primary stage of inflammation of acne.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.59-66
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• 2018

Propionibacterium acnes, a major pathogens bacterium of acne, is one of the microflora associated with the inflammation. In this study, the antibacterial effects of 70% ethanol extracts from the 61 natural plants in Jeju against P. acnes were investigated using the disc diffusion method. The 45 natural plant extracts showed antibacterial effects and the 16 natural plants extracts didn't show antibacterial effects. The Phyllanthus urinaria L. (stem and leaves) extract showed thr highest antimicrobial activity with $18.96{\pm}0.69mm$ clear zone of the growth of P. acnes, followed by Angelica gigas Nakai (roots), Gynostemma pentaphyllum (Thunb.) Makino, Angelica gigas Nakai (stem and leaves), Isodon inflexus (Thunb.) Kudo, camellia sinensis L. (flowers), Rosmarinus officinalis, etc. These results suggest that the natural plant in Jeju can be used as functional cosmetic biomaterials or antimicrobial agents against P. acnes.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.2
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• pp.160-169
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• 2000

This study was conducted to understand the inhibitory garlic and ginger against the growth of food born pathogenic bacteria. Juice was prepared from the raw spices by using an electric homogenizer and membrane filter. Dry-powdered spices were treated with double distilled water and 70% ethanol to extract the antibacterial substances, respectively. Growth inhibitory effects of juice and extracts of the spices were monitored by using bacterial strains such as B. subtilis, L. moncytogenes, S. aureus,E. coli O157 : H7, P. aeruginosa, and S. typhimurium. On a solid medium where E. coli and S. aureus cells were grown, ginger juice formed inhibitory zone at the concentrations of 2-10% by paper disc test. The Bone formed by ginger juice was wider and more transparent than that formed by garlic juice on the same concentration.1. monocytogenes and B. subtilis were more sensitive to garlic juice than others, and stopped growing at 2% garlic juice. Ginger juice showed the growth inhibition by 30-50% at 1.0% concentration. On the contrast, P. aeruginosa which resisted to the garlic juice was the most sensitive to ginger juice. Water extract of garlic was not effective to inhibit the bacterial growth, while 2% ginger extract completely inhibited the growth of E. coli and S. aureus. Alcohol extract of ginger inhibited the growth of bacteria at the concentration of 0.3%. This growth inhibition is almost 10 times lower than that of the garlic extract. It was clear that ginger had more potential than garlic as an inhibitor to control the growth of the indicator organisms.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.2
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• pp.32-41
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• 2001

The purpose of this study is to assess naturalness of each and use type for Daegu and provide the basic data for urban green space planning. The results are as follows: 1) As a result of periodic analysis, It is known that in the 1400´s that the rate of a-/oligo-/meso-hemeroby was over 90% of that area, in which naturalness was very high. By the 2020´s, the population will increase to about 3,500,000 and the occupation rae of meat-and poly-hemeroby, where naturalness is very low, is expected to increase rapidly. 2) The recent land uses of Daegu are divided ito 17 types. In the survey of a occupation rate of each land use type, a forest are occupies 48.8% of the entire area. The military installation zone is lowest with 0.07%. 3) Investigation of a dominant hemeroby grade in each land use type showed that the urban complex area in characterized by meta-hemeroby : and the space for pavement and building construction where naturalness is lowest. On the other hand, oligo-hemeroby that is worth being preserved was surveyed to be dominant in woodlands and natural forests. 4) In the analysis of hemeroby mapping in the process of a green space planning, it is clear that hemeroby will be used a s a tool that assesses the suitability for recreation activity of each sample case. For example, it enables a poly-hemeroby region to be utilized as a near-natural recreation area including $\beta$-and $\alpha$-euhemeroby region in Daegu. Besides, hemeroby can provide basic data to make a value judgement of each sample case with a view to preservation of nature.