• Journal of Mechanical Science and Technology
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• v.17 no.7
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• pp.1104-1110
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• 2003

The present study investigates the hemorheological characteristics of blood flow with applying vibration to a non-aggregating red blood cell suspension. In order to obtain the non-aggregating RBC suspension, blood samples were treated with vibration at a specified condition, which viscosities were taken before and after the treatment, respectively. The viscosity of the blood samples after treatment was higher than before treatment. These treated blood samples were forced to flow through a capillary tube that was vibrated perpendicularly to the direction of the flow. The experimental results showed that vibration caused a reduction of the flow resistance of the non-aggregated blood. The reduction of the flow resistance was strongly dependent on both frequency and amplitude of vibration. These results show potential in treating various diseases in the microcirculation associated with blood cell aggregation.

• Korean Journal of Plant Tissue Culture
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• v.27 no.1
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• pp.47-50
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• 2000

In suspension cultures of Streptanthus. the uptake rate of sugar was increased during the ceil starvation of sugar in the medium. The maximal uptake rate obtained with 3 days of cell starvation. Sugar transport system induced by the sugar starvation was completely inhibited by 10 $\mu$M cycloheximide. Plant cells are known to possess only one sugar transport system, but the uptake rate of glucose obtained a saturated kinetic while the one of sucrose had two different kinetics after the sugar starvation. Induced sugar transport systems had different kinetics compared to plant cell. These results showed that higher plants have adaptable ability to induce new sugar transport systems when the environment changed unsuitable.

• 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.

• Korean Journal of Pharmacognosy
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• v.25 no.1
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• pp.28-30
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• 1994

The rate of growth and production of bioactive substances from Rehmannia glutinosa Liboschitz (Scrophulariaceae) were studied with the variation on the constituents of the culture media. The best growth was observed from MS basal medium containing 3.0 ppm NAA and 2.0 ppm kinetin. Carbohydrates (fructose, glucose and sucrose), phytosterols(${\beta}-sitosterol$, campesterol and stigmasterol) and carotenoid like substances were identified by GC-MS and TLC from the callus mass. However, catalpol was not detected from both solid and cell suspension cultures containing geraniol. Callus cultured Rehmannia glutinosa in the MS basal medium containing 0.1 ppm NAA and 0.1 ppm kinetin become differentiated to root.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.494-499
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• 2004

A method for long-term conservation of somatic embryos of Eleutherococcus senticosos was described. Suspension cultured globular somatic embryos were successfully conservated for 36 months at $4^{\circ}C$. The embryos resumed growth within two weeks when returned to MS liquid medium containing $0.2\;mg/{\ell}$. 2,4-dichlorophenoxy acetic acid. The optimal condition for cell proliferation was achieved when somatic embryos cultured at $32^{\circ}C$ in 1/3 MS liquid medium, and about 1.2 g of embryogenic cell was induced from 150 globular embryos after 6 weeks of suspension culture. The embryogenic cells produced from these somatic embryos exhibited normal plant regeneration on auxin-free medium.

• Journal of Microbiology and Biotechnology
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• v.18 no.11
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• pp.1762-1767
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• 2008

Image contrast of whole bacteria was compared in Staphylococcus aureus and Escherichia coli depending on pre-stain suspension liquids by energy-filtering transmission electron microscopy. The two bacterial strains were suspended in three most commonly used liquids for negative staining (triple distilled water [DW], phosphate-buffered saline [PBS], and nutrient broth [NB]) and directly observed without staining or stained with neutralized potassium phosphotungstate (PTA), respectively. Even though in low contrast, unstained bacteria were observed owing to their inherent electron density and cell shape in zero-loss (elastic scattering) images. After being suspended in PBS, unstained bacteria appeared to have higher contrast and more refined periphery than DW-suspended ones, and extracellular appendage structures such as fimbriae and flagella could be discerned. The unstained bacteria appeared to be invariably surrounded with electron-lucent precipitates, possibly from PBS. As far as delineation of the structures, the combination of DW or PBS suspension with subsequent staining provided the most satisfactory results, as evidenced by the high contrast of bacterial morphology and appendage structures. However, after being suspended in NB and stained with PTA, bacteria often had too high contrast or poor staining, with electron-dense aggregates around the bacteria. These results suggest that suspension with concentrated organic aliquots including broth media before PTA staining could deteriorate image contrast, and should be used only in dilute form for visualizing bacterial morphology and appendage structures. Moreover the contrast enhancement of unstained bacteria by salt granules would be advantageous in demonstrating bacterial sorption of environmental particles like heavy metals, maintaining minimal contrast for cell imaging.

• Journal of Aquaculture
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• v.10 no.4
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• pp.457-462
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• 1997

During the period of the Cochlodinium polykrikoides red tide occurrence in the southern coast of Korea in 1997, we obseved the vertical migration of red tide organisms in situ, along with environmental factors such as water temperature, dissolved oxygen, pH, chlorophyll $\alpha$ and nutrients for practical application of loess suspension techniques ot diminish fisheries damage. To cope with serious outbreaks of red tide of C. polykrikoides, the finfish culturists resorted with loess suspension to disperse the bloom watermass by turning around it with fishing boats in full speed. Peak in afternoon the cell numbers were diminished in the surface layer after sunset red tide organisms settled down in the middle and bottom layer progressively again after sunrise. Chlorophyll $\alpha$ and dissolved oxygen showed the same trends of variation with the cell number. In the course of controlling the red tide with loess suspension we could not find any severs oxygen deficiency to kill the culture species.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.80-80
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• 2005

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.187-188
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• 2005

• Proceedings of the Korean Society of Rheology Conference
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• 2001.06a
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• pp.89-92
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• 2001