• The Korean Nurse
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• v.13 no.3 s.71
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• pp.23-23
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• 1974

• Korean Journal of Plant Taxonomy
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• v.44 no.3
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• pp.181-187
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• 2014

The taxonomic status of a new forma, Opuntia humifusa (Raf.) Raf. f. jeollaensis E. J. Kim & S. S. Whang, and the taxonomic relationships of three Korean cladodes were studied based on DNA sequences of three genes. The new forma O. humifusa f. jeollaensis (Wanggasi-Chunnyuncho) is simlilar to O. humifusa (Chunnyuncho), but differ in having both flower with the reddish inner center, and strong and many 3 cm long spines. Molecular studies showed that the new forma grouped into Macrocentra series instead of Humifusa series which included Korean O. humifusa. We designated the new taxa firstly studied here as a new forma, because the taxa have been mainly cultivated in farmlands in Jeolla-do area rather than distributed in nature. The taxonomic relationships of three Korean cladodes are discussed in detail.

• Journal of the Korea Convergence Society
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• v.8 no.1
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• pp.107-114
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• 2017

To increase the bioavailability of Opuntia humifusa, O. humifusa was fermented using L. plantarum, and the characteristics of the fermented extract were confirmed. The characteristics of fermented extracts were investigated through viscosity, total polyphenol content, amino acid, antibacterial activity, cytokine analysis and zymography. The viscosity decreased by half and vitamin C remained almost unchanged during fermentation. Total polyphenols, most amino acids, total amino acids and major minerals were increased by fermentation. There was no cytotoxicity, and the activity of cytokines and MMP-9 in inflammation was inhibited. The inhibitory effect on inflammation and tissue destruction was found to be inhibited in L. plantarum fermentation extracts compared to hot water extracts. These results are expected to be the basis for the development of materials that enhance the functionality of L. plantarum-fermented O. humifusa extract.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.717-721
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• 2009

The anti-allergic effect of the methanol extract of Zizania latifolia Turcz was investigated. Methanol extract of Z. latifolia Trucz did not display any cytotoxicity activities in the IgE-sensitized RBL-2H3 cells. The extract was found to inhibit compound 48/80-induced degranulation and antigen-induced $\beta$-hexosaminidase release as well as PMA plus A23187-induced TNF-$\alpha$ production in RBL-2H3 mast cells in a dose-dependent manner. Release of $\beta$-hexosaminidase, a marker for the release of histamine in mast cells, was inhibited with an $IC_{50}$ value of $73.8\;{\mu}g/mL$. These results suggest that Z. latifolia extracts may be useful for the prevention of type I allergic reaction.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.56-56
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• 2003

BaTiO$_3$, SrTiO$_3$단일막과 BaTiO$_3$ (BTO)/SrTiO$_3$ (STO) 산화물 인공격자를 pulsed laser deposition (PLD) 법에 의해서 100 nm 두께의 (La,Sr)CoO3 (LSCO) 산화물 전극이 코핑된 MgO 단결정 기판 위에 증착시켰다. 이러한 기판위에서 2 unit cell의 적층 두께를 갖는 BTO/STO 초격자 (=BTO2/STO2)를 100～5 nm까지 변화시켰다. 또한 BTO와 STO 단일막도 같은 두께로 변화시켰다. 이러한 두께 범위에서 BTO, STO 단일막과 초격자의 격자변형에 따른 유전특성을 살펴 보았다. 두께 변화에 따른 단일막과 초격자의 구조 분석은 포항 방사광 가속기의 x-ray 회절에 의해서 이루어졌다. 다양한 두께를 갖는 BTO2/STO2 초격자에서 BTO와 STO 충은 in-plane 방향으로 격자정합을 유지하면서 변형되었다. 두께가 얇아지면서 하부 LSCO영향으로 BTO, STO의 n-plane 격자상수는 LSCO 격자상수 쪽으로 접근하였다. Out-of-plane 방향의 BTO 격자상수는 두께가 얇아지면서 증가하였고 반면에 STO 격자상수는 감소하였다. STO와 BTO 단일막의 격자변형은 두께가 얇아지면서 in-plane 방향으로 압축응력으로 인해 증가하였다. 그러나, 격자부정합도가 큰 BTO격자에서 더 많이 변형되었다. 또한 초격자에서 BTO격자가 BTO 단일막보다 더 많이 변형되었는데 초격자에서는 BTO, STO 두 층의 발달된 변형뿐만 아니라 하부 LSCO/MgO 기판의 영향을 함께 받고 있기 때문이다. 초격자와 단일막의 유전상수를 살펴보면은 두께가 감소하면서 유전상수가 감소하는 size effect을 보이고 있다. 하지만 초격자에서의 유전상수가 단일막보다 우수한 유전특성을 보이고 있다. 이러한 결과로 볼 때 격자변형이 size effect 영향을 끼치는 중요한 요소임을 확인하였다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.12
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• pp.913-919
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• 2015

A supercavitating vehicle has a speed of more than 300 km/h in water. A numerical analysis of the flow around a supercavitating vehicle must deal with a multiphase flow consisting of the water, vapor and exhaust gas because the vehicle is powered by roket propulsion. The effect of the exhaust gas on the vehicle is an important part in the study of the performance of the supercavitating vehicle. In the present study, the effect of the exhaust gas on the drag of vehicle was investigated by conducting numerical analysis. When there is no exhaust gas, drag of vehicle is affected by re-entrant. In the case with rocket propulsion, the exhaust gas reduces the influence of re-entrant. The exhaust gas also creates Mach disk and it changes drag profile.

• Journal of Applied Biological Chemistry
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• v.54 no.4
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• pp.284-289
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• 2011

The extracts of Agrimonia pilosa L. were investigated for the inhibitory effect on the melanin synthesis in B16/F10 mouse melanoma cells as a functional ingredient for cosmetic products. Tyrosinase inhibition activities were 42% in A. pilosa L. 70% ethanol extract at $500{\mu}g/mL$. The protein and mRNA expression of tyrosinase, which are all skin-whitening related factors, showed that A. pilosa L. water and A. pilosa L. 70% ethanol extracts inhibited the protein bio-synthesis in B16F10 melanoma cell. Results indicate that the A. pilosa L. extracts tested in the present study have skin whitening activity and can be used as a functional ingredient for cosmetic compositions.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.334-338
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• 2007

The disinfection effects of trichloroisocyanuric acid (TICA), calcium hypochlorite (CH), and Bromochlorodimethylhydantoin (BCDMH) on various bacteria in aqueous suspension were comparatively characterized at various concentrations and exposure times of each disinfectant. When various bacteria cells ($10^8\;CFU/ml$) including Escherichia coli, Pseudomonas aeroginosa, Enterococcus faecalis, Bacillus cereus, Legionella pneumophila, and Staphylococcus aureus were exposed with a solution containing 8 ppm each of TICA, a 99% of the initial cells were killed in 60 sec, 368 sec, 372 sec, 506 sec, 812 sec, and 909 sec, respectively. In addition, the minimum exposure time required to kill 99% of E. coli ($10^8\;CFU/ml$) with 8 ppm of each TICA, BCDMH and CH was measured at 60 sec, 114 sec, and 7,100 sec, respectively. These comparative studies demonstrate that disinfection efficacy is highly variable depending on microbial species as well as disinfectant type, concentration, and exposure time.

• The Korean Journal of Ecology
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• v.22 no.5
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• pp.271-276
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• 1999

Luminescent patterns of the firefly Hotaria papariensis were classified into routine flashing and courtship flashing, and they were analyzed into duration and period. Flash period of male was changed from 1.26 sec (routine flashing) to 1.12 sec (courtship flashing) and the female's was changed from 2.99 sec to 1.06 sec in this species. Duration time of male increased approximately 1.4-fold from 0.12 sec (routine flashing) to 0.17 sec (courtship flashing) and period of male decreased 0.88-fold from 1.26 sec (routine flashing) to 1.12 sec (courtship flashing). Duration of female increased about 1.5-fold from 0.15. sec (routine flashing) to 0.19 sec (courtship flashing) and period of female decreased almost 0.35 from 2.99 sec (routine flashing) to 1.06 sec (courtship flashing). Hertz frequencies of them were 0.8 (routine flashing of male), 0.9 (courtship flashing of male), 0.3 (routine flashing of female) and 0.9 (courtship flashing of female), respectively. The spectral emission of H. papariensis was detected at 400 nm to 700 nm, and the highest peak wave length of this species was approximately 600 nm, but some 500 to 600 nm wave lengths were present.

• Journal of the Korean association of regional geographers
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• v.23 no.2
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• pp.311-324
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• 2017

This study has the purpose of geopolitical analysis on the role, function and problem of (trans) frontier park in Southern Africa. Frontier parks in Southern Africa had been used as a buffer zone between colonial empires and British colonial administration during the colonial period and as an interdiction zone of communism and black liberation movement during the apartheid regime, the cold war and the civil war. The ecological transfrontier peace parks in Southern Africa which is integrating the adjacent Frontier parks is utilized as a means of a conflict resolution and peace building after the end of cold war, civil war and apartheid regime, The ecological transfrontier peace parks in Southern Africa is very highly regarded as an effective means for a conflict resolution and peace building. But it is also being criticized for a reproduction of South Africa's politico-economic domination and of a socio-spatial division between racial groups.