• Journal of Environmental Science International
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• v.28 no.5
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• pp.511-520
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• 2019

This study was investigated to improve the phosphorus release and water quality by transformation of sedimentary P fraction for application of $CaO_2$. For the experiment, 0.5% (w/w) of $CaO_2$ was homogenized in the sediment and incubated with the control for 20 days. The analytical results showed that pH increased with $CaO_2$ and redox potential (ORP) was improved in the sediment of the reactor. The growth rate of chlorophyll-a was lower in the $CaO_2$ reactor and Dissolved Oxygen (DO) of overlying water maintained higher than that of the control. Total phosphorus (T-P) concentration in the overlying water increased from the initial concentration to 0.304mg/L in the control at 20 days. The reactor of $CaO_2$ was lowered by 29.3%. Ex-P, Fe-P and Ca-P in sediment P fraction were increased with the $CaO_2$. The formation of bound Fe-P and Ca-P in the sediments seemed to control the release of P by removing the Soluble Reactive Phosphorus (SRP) presented in the pore water. From the result, this indicated that the reduction of P release from the sediments seems to be effective in suppressing the eutrophication of P and improving the oxygen condition in the water quality with the application of $CaO_2$.

• Journal of Ginseng Research
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• v.46 no.2
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• pp.225-234
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• 2022

Background: Ginseng, officially known as Panax ginseng Meyer, has been traditionally used as a medicinal herb, particularly in Asia. Ginseng is propagated from seeds; however, seed germination is challenging, especially in its natural environment on farms. The seeds typically exhibit morphophysiological dormancy and require release from both morphological and physiological dormancy before germination. Although some studies have proposed methods for increasing seed germination rates, the underlying mechanisms of its dormancy release process remain unclear. Here, we investigated metabolic alterations during dehiscence in P. ginseng to determine their potential roles in dormancy release. Methods: We compared the ginseng seed metabolome before and after dehiscence and the ginsenoside and phytosterol compositions of the seeds in both periods in the presence of related enzymes. Results: After seed dehiscence, the sugar, amino acid, and squalene concentrations were significantly altered, phytosterols associated with the stigmasterol biosynthesis pathway were increased, while ginsenoside and brassinosteroid levels were not significantly altered. In addition, squalene epoxidase, cycloartenol synthase, 24-methylenesterol C-methyltransferase, and the stigmasterol biosynthesis pathway were activated. Conclusion: Overall, our findings suggest that morphological activities that facilitate ginseng seed growth are the primary phenomena occurring during the dehiscence process. This study improves the understanding of P. ginseng germination processes and promotes further research of its germination and cultivation.

• Analytical Science and Technology
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• v.24 no.4
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• pp.304-309
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• 2011

In this research, behaviour of turbidity and phosphorus in water and soil dependent upon pH and a change of water was studied. Phosphorus dissolve rate from turbidity was increased for water if potential of hydrogen was less than pH 4 or more than pH 7. Turbidity release rate from soil was increased with pH. Turbidity release rate from soil was drastically increased for water if potential of hydrogen was more than pH 4. turbidity release rate from soil was stabilized more than pH 6. Dissolved phosphorus was increased from 2 hours to 24 hours and stabilized in 24 hours. Turbidity was reached the peak of 24 hours and decreased from 24 hours to 96 hours. Turbidity and dissolved phosphorus was decreased for water if these samples were changed a overlying water. Behaviour of turbidity was analogous to dissolved phosphorus when potential of hydrogen was increased from pH 6 to pH 10 and a change of overlying water was increased from 1 time to 4 times. These results suggest that phosphorus dissolve rate and turbidity were directiy correlated with pH. These results are of great importance in lakes because most lakes have a pH in the range of pH 7-10.

• Journal of Life Science
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• v.18 no.11
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• pp.1513-1520
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• 2008

The 4-Hydroxynonenal (HNE) affects vascular dysfunctions probably through the interruption of the cellular redox balance. To better understand vascular abnormalities resulting from the accumulation of HNE, we delineated mechanism by which mitochondrial apoptosis occurs in the YPEN-1 endothelial cells. HNE treatment led to the loss of mitochondrial membrane potential (${\delta}{\Psi}_m$), resulting in the release of cytochrome c. Data showed decreased Bcl-2 and increased Bax protein levels in HNE-treated cells. NAC, a reactive oxygen species (ROS) scavenger, and penicillamine, the peroxynitrite scavenger, blocked HNE-mediated ROS generation, thereby thwarting the cytochrome c release and apoptosis. The treatment of the cells with zVAD-fmk, a broad range caspase inhibitor did not suppress HNE-induced apoptosis, suggesting that the apoptosis might be the possibility of caspase-independent process. Our findings delineate the underlying mechanism of the HNE induced endothelial apoptosis by triggering depolarization of mitochondria membrane potential that can lead to the deterioration of vasculature homeostasis and subsequent vascular dysfunction with aging.

• Biomolecules & Therapeutics
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• v.18 no.1
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• pp.39-47
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• 2010

Brain-derived neurotrophic factor (BDNF) is a neurotrophic factor involved in neuronal differentiation, plasticity, survival and regeneration. BDNF draws massive attention mainly due to the potential as a therapeutic target in neurological diseases such as depression and Alzheimer's disease. In a primary screening for the natural compounds enhancing BDNF release from cultured rat primary cortical neuron, we found that compounds such as baicalein, tanshinone IIa, cinnamic acid, epiberberine, genistein and wogonin among many others increased BDNF release. All the compounds at $0.1{\mu}M$ of concentration barely showed stimulatory effect on BDNF induction, however, their combination (mixture 1; baicalein, tanshinone IIa and cinnamic acid, mixture 2; epiberberine, genistein and wogonin) showed synergistic increase in BDNF release as well as mRNA and protein expression. The level of BDNF expression was comparable to the maximum BDNF stimulation attainable by a positive control oroxylin A ($20{\mu}M$) without cell toxicity as determined by MTT analysis. Both mixtures synergistically increased the phosphorylation of extracellular signal-regulated kinase (ERK) as well as cAMP response element binding protein (CREB), an immediate and essential regulator of BDNF expression. Similar to these results, mixture of these compounds synergistically inhibited the up-regulation of inducible nitric oxide synthase (iNOS) induced by lipopolysaccharide treatments in rat primary astrocytes. These results suggest that the combinatorial treatment of natural compounds in lower concentration might be a useful strategy to obtain sufficient BDNF stimulation in neurological disease condition such as depression, while minimizing potential side effects and toxicity of higher concentration of a single compound.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.56 no.4
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• pp.195-200
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• 2007

This paper describes the countermeasures for preventing the electric shock which can be occurred in the low-voltage handhole underwater. Low-voltage handholes were designed and made for the test in the testing field. Which were installed 4 cases. a metal handhole cover was employed in case 1; FRP(Fiber glass Reinforced Plastic) handhole cover in case 2; an insulated rubber was put on the joint of the cables in case 3; the exposed conductors(cover, frame etc) were commoned and grounded in case 4. Thus, an ground potential near the low-voltage handhole was measured and evaluated quantitatively for the 4 cases. The measured results show that the potential of case 2.3 were lower than that of case 1 because the insulated rubber and the FRP cover prevented direct contact to the fault point. The case 4 is the lowest among the 4 cases because the common and grounding helps the fault current release into the ground, which makes the ground potential rise lower. As a result, although each case has the defects, these ways can effectively lower the electric shock risk in the low-voltage handhole.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.1
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• pp.43-53
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• 2019

In the Geumho River, 4-nitrophenol has been detected, thus it is necessary to investigate the contamination sources in order to prevent the release of this compound. However, the research to estimate the potential source is regarded as complicated research. In this study, the distributions of 4-nitrophenol were simulated and the contribution of the potential sources was estimated using a numerical model(HydroGeoSphere; HGS) and the measuring data of 4-nitrophenol from 2013 to 2017. The altitude data, the land cover data, the flow rates of the tributaries and wastewater treatment plants, and the decay rate of 4-nitrophenol was used as the input data. The results of this research showed that the contribution rates of potential contamination sources in the upstream area were higher than that of the downstream area. Most of the upstream area is the agricultural area, it seemed that 4-nitrophenol was originated from the pesticides. In order to achieve more specific location of sources, an intensive investigation in the upstream is required.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.187-188
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• 2003

Conadotropin releasing hormono analogs (GnRHa) have now been tested successfully a range of marine and freshwater species and been shown to be an effective strategy for improving milt quantity and quality (Mylonas and Zohar, 2001; Zohar and Mylonas, 2001; Lim et at, , 2002). Greenback flounder (Rhombosolea tapirina) is currently under consideration as a potential culture species in south-eastern Australia. (omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.39-39
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• 2002

Microglia are known to have an important function as brain macrophage during immunological processes, oncogenesis, and regeneration in the central nervous system (CNS). A wide variety of ion channels have been identified and characterized in microglia including inward rectifier $K^{＋}$ channel (Kir), voltage dependent $K^{＋}$ channel (Kv), $Ca^{2＋}$-release activated $Ca^{2＋}$ channel (CRAC).(omitted)

• Proceedings of the Korean Society of Applied Pharmacology
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• 2007.11a
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• pp.67-73
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• 2007

There have been various inflammatory skin disorders in humans including atopic dermatitis, eczema and psoriasis. Although some drugs have been used for these disorders, there is an urgent need for safer and more effective topical anti-inflammatory agents. Plant flavonoids possess anti-inflammatory activity and some of them have multiple pharmacological mechanisms, inhibition of eicosanoid metabolizing enzymes, histamine release and/or down-regulation of pro inflammatory gene expression. These properties of flavonoids may be suitable for treating chronic skin inflammatory disorders. Especially, wogonin, some prenylated flavonoids and biflavonoids have a strong potential as new anti-inflammatory agents by topical application.