• Korean Journal of Materials Research
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• v.10 no.6
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• pp.445-449
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• 2000

Nickel ferrite $(Ni_{0.75}Fe_{2.25}O_4$ was synthesized by co-precipitation method in order to investigate its behavior under conditions of the reactor coolant system in pressurized light water nuclear power plants. Ammonia or potassium carbonate was used as a solution pH control agent, and aqueous ammonia or potassium carbonate solution or secondary distilled water was used as a co-precipitate washing agent. The effects of the pH control agent and the co-precipitate washing agent on the production yield on the basis of the Ni/Fe molar ratio and the particle characteristics of final products were investigated by XRD, SEM, EDX and XPS. The production yield was almost congruent with that of the initial aqueous mixture in case of using potassium carbonate as a pH control agent, while in case of using ammonia, it was quite changed. The difference seemed to be due to the effects of $Ni^{2+}{\leftarrow}NH_3$complexation in the aqueous solution and of the pH of co-precipitate washing agent.

• Journal of Life Science
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• v.23 no.12
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• pp.1553-1556
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• 2013

Flavonoids are one of the major components found in the peels of citrus fruits. Present evidence has suggested that polymethoxyflavonoids, including nobiletin and tangeretin isolated from Citrus sunki, have many biological properties, such as anti-inflammatory, anti-oxidant, and anti-obesity capabilities. Here, we investigated the effect of Citrus sunki peel extract and its possible mechanisms on oxidative stress-induced MMP-1 expression, a major marker of skin photoaging. $H_2O_2$ induced MMP-1 expression in a dose- and time-dependent manner. Extract of Citrus sunki peel (1-25 ${\mu}g/ml$) dose-dependently decreased MMP-1 mRNA levels. When $H_2O_2$ was combined with Citrus sunki peel extract, the phosphorylation of ERK was further decreased compared to a single treatment with $H_2O_2$ alone. Moreover, U0216, an MEK inhibitor, markedly prevented the production of MMP-1. These data suggest that Citrus sunki peel extract has demonstrated protective activity against oxidative damage on MMP-1 expression, and ERK MAP kinase may be involved.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1995.04a
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• pp.64-65
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• 1995

양액재배는 토양재배보다 시설비가 많이 든다는 것을 제외하고는 여러 가지 면에서 유리하다. 우리나라의 양액재배 면적은 1994에 59.5ha로서 앞으로 그 면적은 급속도로 늘어날 전망이다. 양액재배가 성립되려면 몇 가지 요건들이 갖추어져야 하는데 그 중 용수의 수질상태는 매우 중요하다. 용수로써 사용되는 물은 주로 지하수, 하천수, 수도물, 빗물 등인데 우리나라는 대부분 지하수를 이용하고 있다. 용수중 무기성분의 농도는 순수한 물이 이상적이지만 가능한 한 그 농도가 낮은 것이 좋다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.11a
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• pp.1-12
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• 1999

식물생육에 필요한 모든 물질 가운데 가장 많이 요구되는 것이 물이다. 물은 가장 많이 흡수하는 물질인 동시에 가장 많이 소실되는 물질이기도하며 또한 가장 다양한 기능을 가진 물질이기도 하다. 모든 식물은 그들의 생장과 분화과정에서 물의 공급량에 대하여 매우 예민한 반응보인다. 이러한 민감한 반응은 고착생활을 하는 식물이 주어진 생육환경의 조건을 감수하면서 수분 결핍이나 건조로부터 스스로 보호하려는 필수적인 현상이다. (중략)

• Journal of Life Science
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• v.28 no.3
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• pp.376-387
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• 2018

Among a variety of environmental stresses heat, cold, chilling, high salt, drought, and so on exposed to plants, drought stress has been reported as a crucial factor to adversely affect the growth and productivity of plants. Therefore, to understand the mechanism for the drought stress signal transduction pathway in plants is more helpful to develop useful crops that display the enhanced tolerance against drought stress, and to expand crop growing areas. The signal transduction pathway for the drought stress in plants is largely categorized into two types; ABA-dependent pathway and ABA-independent pathway. It has been reported that two transcription factors, AREB/ABF and DREB2, play predominant roles in ABA-dependent and ABA-independent pathways, respectively. In addition to transcriptional regulation mediated by AREB/ABF and DREB2 transcription factors, post-translational modification (such as phosphorylation and ubiquitination) and epigenetic control are importantly involved in the signal transduction for drought stress. In this paper, we review current understanding of signal transduction pathway on drought stress in plants, especially focusing on the biological roles of a variety of signaling components related to drought stress response. Further understanding the mechanism of drought resistance in plants through this review will be useful to establish theoretical basis for developing drought tolerant crops in the future.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.11a
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• pp.279-284
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• 2002

생물생산에 따른 생산시설 및 환경조절에 대한 생물 환경 조절 시스템은 식물이나 동물과 같은 생물을 보호하기 위한 간단한 구조물에서 환경조절, 생물의 성장, 그리고 공간과 노동력의 이용 둥이 효율적으로 상호 작용하는 복잡하며 정교한 시스템도 있다. 이 시스템이 어떠한 형태로 구성되어있더라도, 가장 중요한 목표는 시스템이 이루고자 하는 목적을 달성하고, 경제적인 이윤을 남기고 또한 경제적으로 살아남을 수 있는가에 있다. (중략)

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.943-947
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• 1995

The sweet potato drinks were prepared with the reaction of sweet potato and complex enzyme(${\beta}-amylase,\;{\alpha}-amylase$, protease). The reducing sugar and soluble solid of sweet potato drinks were the highest on reaction of sweet potato : water(1 : 1) and complex enzyme(pH 4.5). In the color of the sweet potato drinks, hunter value(L, a, b) were the lowest on reaciton of sweet potato : water(1 : 1) and complex enzyme, and were the highest on reaciton of sweet potato : water(1 : 3) and complex enzyme(pH 4.5). In the sensory test of the sweet potato drinks, the sensory score(color, taste, flavor, texture) were the best on reaction of sweet potato : water(1 : 1) and complex enzyme(pH 4.5). These results demonstrated that the sweet potato drink was good to drink when sweet potato : water(1 : 1) were treated with complex enzyme at pH 4.5, $60^{\circ}C$ for 5 hrs.

• Monthly Duck's Village
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• s.36
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• pp.18-38
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• 2006

• Journal of the Korea Convergence Society
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• v.13 no.5
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• pp.113-117
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• 2022

In this study, the antibacterial and phagocytosis regulation effects of Hordeum vulgare extract and pine needle extract on S. mutans, the causative bacteria of dental caries, were investigated. Ethanol extracts of domestic Hordeum vulgare powder and pine needle powder were used, and the antibacterial and phagocytic ability against S. mutans was confirmed according to the concentration of the extracts. As a result, S. mutans colony formation did not show a significant difference in the Hordeum vulgare extract but was significantly decreased in the pine needle extract. As a result of confirming the phagocytic ability of THP-1 cells for S. mutans, there was no significant difference in the Hordeum vulgare extract, but the phagocytic ability of immune cells was improved in the pine needle extract. Therefore, it suggests that pine needle extract can be used as a material for preventing dental caries.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2000.10a
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• pp.81-84
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• 2000