• Journal of Food Hygiene and Safety
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• v.2 no.4
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• pp.191-196
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• 1987

Erythrosine used as a colouring agent in drugs, cosmetics and foods in Korea, was examined for its effects on murine immune system and methemoglobin formation. As immunotoxicologic assay parameters, we adopted circulating leukocytes and immunoorgan weights for pathotoxicology, IgM plaque forming cells and arthus reaction for humoral immunity, delayed hypersensitivity reaction of cell mediated immunity and carbon clearacnce for macrophage function. Erythrosine's effects were observed as follows; 1. Ery throsine showed no significant effects on circulating leulocyte counts and relative immunoorgan weight. 2. Erythrosine diminished IgM plaque forming cells. 3. Erythrosine decreased arthus reaction, in the dose dependent manner. 4. Erythrosine had no significant effect on delayed hypersensitivity. 5. Phagocytic and corrected phagocytic index were not affected. 6. Methemoglobin content was similar in the test and control groups.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.223-229
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• 1999

The two optimal control algorithms, singular approximation and minimum principle, were compared in this paper. The switching time with singular approximation was determined with mathematical derivation and the optimal control profile of specific growth rate was also calculated with minimum principle. The optimal control profiles were calculated by making simple model correlating the specific cell growth rate and specific product formation rate. The optimal control profiles calculated by singular approximation approach were similar to stepwise form of those calculatd by minimum principles. With the minimum principle, the product concentration was 8% more than that of singular approximation. This performance difference was due to a linearization of a nonlinear function with singular approximation. This optimal approaches were applicable to any system with different optimal cell growth and product formation.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.20-20
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• 2002

This study was to establish the use of parthenogenetic mouse ES (P-mES02) cells as a reproducible differentiation system for mouse cardiomyocytes. To induce differentiation, P-mES02 cells were dispersed by dissociation and the formation of ES cell aggregates in differentiation medium. After 7 days in differentiation culture, the embryoid bodies (EBs) were plated onto gelatin-coated dish. Cultures were observed daily using an inverted light microscope to determine the day of contraction onset and total duration of continuous contractile activity for each contracting focus. (omitted)

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.4
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• pp.285-293
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• 2004

In this study, a machine grouping problem for the formation of manufacturing cells is considered. We constructed the problem as minimizing manufacturing leadtime consisting of parts' processing, moving, and waiting time. Specifically, the main objective of the defined problem is established as minimizing inter-cell traffic in order to minimize the part's moving time. In addition, to reduce the waiting time of parts, the load balance among cells is implicitly included as constraints. Since this problem is well known as NP-complete and cannot be solved in polynomial time, a genetic algorithm is implemented to obtain solutions. Also, a local optimization algorithm is applied in order to improve the solution by the genetic algorithm. Several experiments show that the suggested algorithms guarantee near optimal solutions in a few seconds.

• Journal of Pharmacopuncture
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• v.11 no.1
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• pp.143-147
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• 2008

Objectives : This study was carried out to investigate the antioxidant effects of Jeondo-san(JDS). Methods : The antioxidant effects of JDS were measured by the scavenging for 2,2-Diphenyl-1-picrylhydrazyl(DPPH) radical, the formation of intracellular glutathione(GSH), the inhibition for reactive oxygen species(ROS). Results : 1. All concentrations of JDS showed antioxidant effect by decreasing the DPPH radicals. 2. All concentrations of JDS did not effect on the formation of intracellular GSH in HaCaT cell. 3. All Concentrations of JDS inhibited the production of ROS in the HaCaT cell stimulated with $H_2O_2$. Conclusion : The present date suggest that JDS has effects on the stage of inflammation.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.307-310
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• 2002

A two-dimensional numerical method for inviscid two-fluid flows with evolution of density interface is developed, and an initially stationary two-dimensional fluid sheet surrounded by another fluid is studied. The Interface between two fluids is modeled as a vertex sheet, and the flow field u÷th the evolution of interface is solved by using vortex-in-cell/front-tracking method. The edge of the sheet Is pulled back into the sheet due to surface tension and a blob is formed at the edge. This blob and fluid sheet are connected by a thin neck. In the inviscid limit, such process of the blob and neck formation is examined in detail and their kinematic characteristics are summarized with dimensionless parameters. The edge recedes at $V=1.06({\sigma}/{\rho}h)^{0.5}$ and the capillary wave Propagating into the fluid sheet must be considered for bettor understanding of the edge receding.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.169-169
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• 2017

Due to key roles for the electrochemical stability and charge capacity the solid-electrolyte interphase (SEI) has been extensively studied in anodes of a Li-ion battery cell. There is, however, few of investigation for cathodes. Using first-principles based calculations we describe atomic-level process of the SEI layer formation at the interface of a carbonate electrolyte and $LiMn_2O_4$ spinel cathode. Furthermore, using beyond the conventional density functional theory (DFT+U) calculations we examine the work function of the cathode and frontier orbitals of the electrolyte. Based on the results we propose that proton transfer at the interface is an essential mechanism initiating the SEI layer formation in the $LiMn_2O_4$. Our results can guide a design concept for stable and high capacity Li-ion battery cell through screening an optimum electrolyte fine-tuned energy band alignment for a given cathode.

• The Journal of Korean Medicine
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• v.23 no.2
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• pp.28-38
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• 2002

Objectives : This study was to examine the efficacy of GCT on the hepatoprotective effect in the liver function and immune octivity. Methods : The experiment to investigate the hepatoprotective effect of GCT on the liver damage was conducted with D-galactosamine. The experiments to verify the effects of GCT on the immune activity were conducted by carbon clearance assay, plaque-forming cell SRBC assay of IgM, lymphoproliferation assay of T and B cells, and adherence and phagocytosis of mocrophages. Results: In the damage of liver induced by D-galactosamine, GCT carried hepatoprotective effect on AST. In carbon clearance assay GCT showed significant effect on phagocytosis of Kuffer cells. In the plaque-forming cell assay, GCT improved the formation of IgM. In the lymphoproliferation assay, GCT activated the formation of T and B lymphocytes. In macrophages, GCT activated adherence and phagocytosis. Conclusion : Though further study is needed, our findings suggest that GCT could be recommended as hepatoprotector and immune modulator for liver disease.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.651-658
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• 1994

For the production of digoxin by using biotransformation in suspension-cultured Digita- lis lanata cells, a two-stage culture process was optimized. Modified Murashige and Skoog medium was used for growth in the first stage and the cells were transferred to glucose solution for the production of digoxin from digitoxin via biotransformation in the second stage. When the cells were cultivated for 10 days in the growth period, 12$\beta$-hydroxylation capacity was the best. It was found that the optimum amount of digitoxin as substrate was 400 mg/l with initial cell density of 21%. Maximum productivity was achieved 5 days after transfer of cells to production medium. Sucrose and fructose provided similar digoxin yield as that in glucose, and 6% was proved to be the best glucose solution. Most of the components of modified MS medium except phosphate reduced the efficiency of digoxin formation. Besides, peptone and beef extracts inhibited 12$\beta$-hydroxylation, while promoting glucosylation. Finally, it was apparent that light enhanced the formation of digoxin significantly.

• Biomolecules & Therapeutics
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• v.6 no.3
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• pp.269-275
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• 1998

These studies were conducted to investigate the antiinflammatory effects and the mechanism of action of natural products. We used the methods of "carrageenan induced foot edema" , "PAF (platelet activating factor) induced foot edema" , "inhibition test of vascular permeability" , "inhibition test of white blood cell migration" , "formation of granuloma" and "adjuvant induced arthritis" to examine the antiinflammatory erects of Angelica gigas, Ledebouriella seseloides, Ginkgo biloba and Bamboo salt (Jukyom). The oral administration of the water extract of Angelica gigantis radix, the methanolic extract of Ginkgo folium and the aqueous solution of Bamboo salt showed antiinflammatory effect on carrageenan and PAF induced foot edema in SD rat at a dose of 1 g/kg. The same administration of methanolic extract of Ginkgo folium also inhibited the vascular permeability in mice. The aqueous solution of Bamboo salt inhibited the formation of ganuloma in SD rats at a oral dose of 1 g/kg. Angelica gigantis radix seems to have antiinflammatory effect by inhibition of PAF.