• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.181-187
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• 2000

Fatigue tests under acid fog environment were carried out to investigate the effect of acid fog on the corrosion fatigue strength of SM55C in comparison with distilled water. Main results obtained are as follows. The fatigue strength of SM55C under acid fog environment are remarkably decreased as compared with that of distilled water specimen. The corrosive effect of acid fog on fatigue strength are more serious under low stress amplitude level than under high stress amplitude level, and this leads to continuous reduction of fatigue strength. Under acid fog environment in early stage of crack growth. because the corrosive components dissolve the crack face offensively. the unstable fracture surface appears. But, the stable corrosion precipitation and products layer are formed on the fracture surface in accordance with the time pass.

• Journal of Microbiology and Biotechnology
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• v.20 no.12
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• pp.1677-1680
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• 2010

The harmful effects of succinic acid and oxidative stress on cell growth were determined during batch fermentation with Mannheimia succiniciproducens LPK7, a powerful succinic acid-producing strain, and conditions were optimized to minimize these effects. In terms of toxicity, the cell concentration decreased as the concentration of succinic acid increased. By changing the pH from 6.5 to 7 during fermentation, the cell concentration increased by about 10%, and the level of succinic acid production was 6% higher than that of the control. In addition, by introducing protectants, the cell concentration increased by about 10%, and the level of succinic acid produced was increased by 3%.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.556-563
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• 2005

Homogentisic acid was found to scavenge intracellular reactive oxygen species (ROS), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and thus prevented lipid peroxidation in human fibroblast (Wl 38) cells. The radical scavenging activity of homogentisic acid was found to protect Wl 38 cells against hydrogen peroxide $(H_2O_2)$ induced oxidative stress, via the activation of extracellular signal regulated kinase (ERK) protein. Homogentisic acid increased the activity of catalase. Hence, from the present study, it is suggested that homogentisic acid protects Wl 38 cells against $H_2O_2$ damage by enhancing the intracellular antioxidative activity.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.270-276
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• 1999

Production of stress shock proteins in Burkholderia cepacia YK-2 in response to the phenoxyherbicide 2,4-dichlorophenoxyacetic acid(2,4-D) as an environmental contaminant was investrigated. The stress schock proteins were synthesized at different 2,4-D concentrations in exponentially growing cultures of B. capacia YK-2. This response involved the production of 43kDa and 41kDa GroEL proteins. The proteins were characterized by SDS-PAGE and Western blot using the anti-DnaK nad anti-GroEL monoclonal antibodies. Total stress shock proteins were analyzed by 2-D PAGE. Survival of B. cepacia YK-2 with time in the presence of different concentrations of 2,4-D was monitored, and viable counts paralleled the production of the stress shock proteins in this bacterium.

• Journal of Plant Biotechnology
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• v.4 no.2
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• pp.53-58
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these "environmental or abiotic stresses", which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity, In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.n factors.

• Journal of Plant Biotechnology
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• v.29 no.4
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• pp.277-280
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• 2002

Acid phosphatase in the radish young plant showed optimal activity at pH 5.5. The activity of acid phosphatase was maintained longer during the ABA (0.5 mM) treatment than those in control, whereas that was similar to the treatment of NaCl (0.5 mM). But during the cold (4$^{\circ}C$) treatment, the activity of acid phosphatase was decreased dramatically compared to the control, which was maintained almost on a constant level and increased gradually during 6 days. It showed that acid phosphatase was in relation to the change of biochemical reaction, which plants were coped with cold, NaCl and ABA stress.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.61-68
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• 2017

Gibberellic Acid-Stimulated Arabidopsis (GASA) genes are involved in plant hormone signaling, cell division and elongation, as well as in responses to stress conditions in plants. In this study, we isolated a GASA gene from hybrid poplar (Populus alba ${\times}$ P. glandulosa) and analyzed its physiological phenotype and molecular functions in poplar. PagGASA cDNA encodes a putative protein composed of 95 amino acids containing an N-terminal signal peptide and a conservative cysteine-rich C-terminal domain. Southern blot analysis revealed that one or two copies of the PagGASA are present in the poplar genome. The PagGASA transcripts were highly detected in flowers and roots. Moreover, the expression of PagGASA was induced by growth hormone (gibberellic acid) and stress hormones (abscisic acid, jasmonic acid, and salicylic acid). By using transgenic analysis, we showed that the upregulation of PagGASA in poplar provides high tolerance to drought stress. Therefore, our results suggest that PagGASA plays an important role in drought stress tolerance via stress-related plant hormone signaling in poplar.

• The Korea Journal of Herbology
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• v.38 no.2
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• pp.1-7
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• 2023

Objectives : From this study, we sight to identify Anti-stress effect of Chenwangbosim-Dan (Tianwangbuxin-Dan) Extract∘Fermented Rice Extract (GABA : gamma-aminobutyric acid 30%) Complex Methods : In order to measure the degree of functional evaluation of tension relief due to stress, it was evaluated whether the psychological indicators VAS(Visual Analog Scale) and POMS(Profile Of Mood State) were improved. Which is generally used for stress measurement and has a high frequency of clinical use. All clinical trial subjects were required to take the drug once a day at 9 ± 30 min in the morning for 2 weeks. Results : After intake, the group that Chenwangbosim-Dan(Tianwangbuxin-Dan) Extract∘Fermented Rice Extract (GABA : gamma-aminobutyric acid 30%) Complex had a statistically significant improvement effect compared to before intake due to an improved 30.81% of the VAS scores. The POMS-T score improved 54.13%, the POMS-V score improved 117.5% and the POMS-F score improved 59%, which had a statistically significant effect compared to Placebo group (p<0.001). There is a significant difference between two group, so even considering the placebo effect, the anti stress effect was confirmed in the Chenwangbosim-Dan (Tianwangbuxin-Dan) Extract∘Fermented Rice Extract (GABA : gamma-aminobutyric acid 30%) Complex intake group. Conclusions : The above results showed that the Chenwangbosim-Dan(Tianwangbuxin-Dan) Extract∘Fermented Rice Extract (GABA : gamma-aminobutyric acid 30%) Complex had an anti-stress effect. Therefore, it is expected to be developed as a safe and comfortable mental care health functional food that can reduce the risk of drug abuse.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.3-4
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• 2009

한국인 아동의 우식치아로부터 S. mutans를 분리하고, acid stress하에서 분리한 S. mutans의 내산성 능력과 관련된 단백질을 규명하고자 하였다. S. mutans의 16S rDNA 유전자 핵산염기서열을 바탕으로 설계된 프라이머 쌍을 이용하여 중합효소연쇄반응을 실시하고 16S rDNA sequencing을 실시한 결과, 한국인 아동으로부터 분리 된 S. mutans K7은 기존에 보고된 표준균주와 99.9% 일치하는 결과를 나타내 S. mutans로 판명되었다. 또한 2D gel electrophoresis 를 수행한 결과, acid stress에 관여하는 것으로 추정되는 단백질들을 확인 할 수 있었다.

• Journal of Korean Biological Nursing Science
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• v.19 no.3
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• pp.141-150
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• 2017

Purpose: The purpose of this study was to investigate the effects of the Korean Dietary Approaches to Stop Hypertension (DASH) education program on oxidative stress, antioxidant capacity, and serum homocysteine (Hcy) level in elderly Korean women. Methods: This was a quasi-experimental study employing non-equivalent control group pretest-posttest design. The DASH group (n= 27) underwent the DASH education program for 12 weeks, whereas the control group (n= 21) was provided one education session. The survey was conducted before and after the intervention period. Results: In DASH group, monounsaturated fatty acid (MUFA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) intakes significantly increased after the intervention as compared to prior to the intervention. No significant differences were found in the control group. After the intervention, thiobarbituric acid reactive substance (TBARS) and Hcy levels significantly decreased in the DASH group but not in the control group. Conclusion: The DASH education program was effective in reducing oxidative stress and Hcy levels in elderly Korean women.