• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.418-422
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• 2005

In this study, the die design and die series on the surface residual stress of cold drawn eutectoid steel wire has been investigated. Test pieces were fabricated using die series with different mean and final reduction ratio. Surface residual stresses in the axial direction were measured by X-ray diffraction, Broker's 2-dimensional GADDS system. Results were compared with stress profiles which were calculated by 3D and 2D finite element simulation, Hibbitt's ABAQUS 6.4 program in Finite Element Analysis. By means of FEA method, optimal die shape considering delta-parameter were induced and applied in order to determine die sequence designs. Balance of the drawing stresses was also introduced to optimize die sequence.

• Journal of Plant Biology
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• v.37 no.1
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• pp.27-36
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• 1994

For establishing a transformation system of rice, an efficient introduction of foreign genes into embryogenic cell suspension by particle bombardment was conducted. The particle inflow gun based on the acceleration of DNA-coated tungsten particles using pressurized helium was constructed for delivery of DNA into rice cells. Several bombardment parameters were optimized using the transient expression of GUS gene. The conditions that gave the highest GUS gene expression of about 1000 blue spots per g fresh weight of bombarded cells include treatment of the cells with 0.5 M osmotic pressure, and use of the 410 kPa helium, 110 mm target distance, 13 mm syringe filter holder and 5 $\mu$L DNA/tungsten mixtures. It was also confirmed that rice actin promoter-intron construct gave the highest expression of all promoter-sequences studied. Eight weeks after the bombardment, stably transformed calluses were obtained on the selection medium containing 100 mg/L G418 and showed the strong activity in in situ GUS assay.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.418-424
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• 2018

${\text\tiny{D}}-Allose$ is a potential medical sugar because it has anticancer, antihypertensive, antiinflammatory, antioxidative, and immunosuppressant activities. Allose production from fructose as a cheap substrate was performed by a one-pot reaction using Flavonifractor plautii ${\text\tiny{D}}-allulose$ 3-epimerase (FP-DAE) and Clostridium thermocellum ribose 5-phosphate isomerase (CT-RPI). The optimal reaction conditions for allose production were pH 7.5, $60^{\circ}C$, 0.1 g/l FP-DAE, 12 g/l CT-RPI, and 600 g/l fructose in the presence of 1 mM $Co^{2+}$. Under these optimized conditions, FP-DAE and CT-RPI produced 79 g/l allose for 2 h, with a conversion yield of 13%. This is the first biotransformation of fructose to allose by a two-enzyme system. The production of allose by a one-pot reaction using FP-DAE and CT-RPI was 1.3-fold higher than that by a two-step reaction using the two enzymes.

• Korean journal of food and cookery science
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• v.20 no.4
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• pp.418-422
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• 2004

We investigated microbial populations of an upland and cultivated Codonopsis lanceolata. The microbial populations from both types of soils were also investigated. There were more than 10 microorganisms existed in upland than cultivated one. The total viable cell counts of C. lanceolata from upland and cultivated one, especially in the upper zone, were 9.7x10$\^$6/ CFU/g and 4.2${\times}$10$\^$6/ CFU/g, respectively. As a results, upper parts of C. lanceolata in upland were considered to harbour approximately more than 2.3 fold higher microorganisms than in cultivated one. However, the total viable cell counts between the two soil habitat, that is, 1.2${\times}$10$\^$7/ CFU/g from upland and 1.0x10$\^$7/ CFU/g from cultivated, were not significantly different. We also examined the unique flavor producing microorganisms in the soil extract broth including 25% C. lanceolata extract. One microorganism was detected in upper pars of C. lanceolata and upland soil. No. 6, microorganism causing the characteristic flavor of C. lanceolata was continued as Actinomyces by microscopy.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.5
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• pp.411-418
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• 2000

The purpose of this study was to investigate the sensory and mechanical characteristics of mayonnaise containing various levels of green tea powder The highest viscosity of mayonnaise was obtained at the green tea powder concentration of 0.5% The emulsion, stability was increased with the addition of green tea powder. In the sensory evaluation, overall acceptabilty appeared to be the highest when 0.1% of green tea powder was added. There was a significant difference between the samples (P<.05) In terms of change in color, the values of L, a, b, and ΔE decreased as the amount of green tea powder increased. In the measurement of the texture, the hardness of mayonnaise was highest in the control of green tea powder, and the springiness appeared to be higher in the mayonnaise with 0.1% of green tea powder. The odor acceptabilty in the sensory evaluation showed a negative correlation with the values of gumminess in the mechanical characteristics. The subjective parameters that affect overall quality on sensory evaluation were determined by, and they were odor acceptabilty, after taste, oily taste, sour odor. sweet taste. egg odor, color acceptabilty, and salty taste. These results showed that mayonnaise made with 0.1% green tea powder, salad oil 474.5ml. egg golk 85g, sugar l0g, salt 7g, and vinegar 23m1 with the addition of 0.6g green tea powder was the most effective compared with other treatments.

• Polymer(Korea)
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• v.39 no.3
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• pp.418-425
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• 2015

Polycaprolactone (PCL) and biphasic calcium phosphate (BCP) have been considered as useful materials for orthopedic devices and osseous implants because of their biocompatibility and bone-forming activity. However, PCL-based scaffolds have hydrophobic surfaces reducing initial cell adhesion or proliferation. To overcome the limitation, we fabricated surface-modified PCL/BCP nanofibers using gamma-irradiation for bone tissue engineering. PCL/BCP nanofibers were prepared by electrospinning and then we supplemented hydrophilicity by introducing acrylic acid (AAc) through gamma-irradiation. We confirmed the surface of nanofibers by SEM, and then the initial viability of MG63 was significantly increased on the AAc grafted nanofibers, and alkaline phosphatase activity($1.239{\pm}0.226nmole/{\mu}g/min$) improved on the modified nanofibers than that on the non-modified nanofibers($0.590{\pm}0.286nmole/{\mu}g/min$). Therefore, AAc-grafted nanofibers may be a good tool for bone tissue engineering applications.

• Journal of Embryo Transfer
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• v.22 no.3
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• pp.179-184
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• 2007

Culture method of somatic cells is one of the important factors in the production of transgenic pigs by somatic cell nuclear transfer. In this study, we established an efficient culture method of porcine fetal fibroblasts. Porcine fetal fibroblasts were isolated from 33-day-old fetuses. The proliferation of porcine fetal fibroblasts was analyzed by different serum types and culture media. The cultures in medium supplied 15% ES screened FBS showed faster increase in cell number than 15% FBS. Also, fetal fibroblasts have been propagated continuously for $7{\sim}8$ passages in ES modified DMEM and DMEM medium. We transfected $PGK-neo^r$ vector (pKJ2) into porcine fetal fibroblasts to estimate colony formation in this culture condition. The formation of colonies was confirmed in the medium containing $300\;{\mu}g/ml$ G418 at 12 day. These data show that this culture system can be used screening of porcine somatic cells transfected transgene.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.7
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• pp.418-425
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• 2015

Anaerobic Filters (AF) packed with porous ceramic floating media were operated at different operational conditions to identify the feasibility of the renewable bioenergy, methane production from swine wastewater and to verify the suitability of effluent from anaerobic filters for the subsequent biological nitrogen and phosphorus removal. Stepwise increase in organic loading rates (OLRs) or decrease in hydraulic retention times (HRTs) with influent TCOD concentration of 14,000 mg/L were utilized at mesophilic temperature. The maximum methane productivity of 1.74 volume of $CH_4$ per volume of reactor per day (v/v-d) was achieved at an hydraulic retention time (HRT) of 0.5 day (OLR 28 g TVS/L-d). Based on the biogas production, the highest total volatile solids (TVS) removal efficiency of 63% was obtained at an HRT of 3 days (OLR 4.67 g TVS/L-d), however based on the result from the effluent total chemical oxygen demand (TCOD) analysis, the highest TCOD removal efficiency of 75% was achieved. The effluent alkalinity concentration over the range of 2,050~2,980 mg/L as $CaCO_3$ at all operational conditions, could compensate the alkalinity destruction caused by nitrification. The effluent from the anaerobic filter operated under the HRT of 2 days showed the COD/TKN ratio of 15~35 and COD/TP ratio of 38~56. Therefore effluent C/N/P ratio is able to satisfy the optimum COD/TKN ratio of greater than 8.0 and COD/TP ratio of 33 for the subsequent biological nutrient removal.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.6
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• pp.418-421
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• 2000

A new direct colorimetric assay of microcystin in water and algal samples is proposed consisting of two procedures as follows: 1) the elimination of phosphorus in the sample and concentration of microcystin using a C(sub)18 cartridge, 2) the detection of the released phosphorus by the ascorbic acid method and determination of protein phosphatase (PP) inhibition by microcystin. The optimum amounts of phosphorylase ${\alpha}$ and PP-1 in 50 ${\mu}$L concentrated sample were 50$\mu\textrm{g}$/50${\mu}$L buffer and 1.0unit/50${\mu}$L buffer, respectively, for the best assay. The pH for the maximum activity of PP-1 was 8. The minimum detectable concentration for this method was about 0.02$\mu\textrm{g}$/L, which is sufficient to meet the proposed guideline level of 1$\mu\textrm{g}$ microcystin/L in drinking water. Consequently, it would seem that the proposed direct colorimetric assay using PP is a rapid, easy, and convenient method for the detection of microcystin in water and algal samples.

• Journal of Fisheries and Marine Sciences Education
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• v.15 no.2
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• pp.135-144
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• 2003

1. The appearance of fisheries animals and plants of investigation areas were fishes, 20 species; algae, 9 species; molluska, 6 species; arthropod, 12 species; echinoderm, 5 species by confirmed appearance species. 2. The C.P.U.E by trap(1pcs of trap) were 3.95 species and weight of 2,098g, mainly catching species are greenling and jacopever(94.16%). The C.P.U.E by long liner(long liner 1coil, 100pcs) were 11.7species and weight of 6,418g, It occupied jacopever(35.63%) greenling(20.78%), bastard halibut(20.31%). The C.P.U.E of appearance species gill net(ipcs of gill net) were 5.05species and weight of 3,050g, It occupied jacopever(39.63%) greenling(29.83%), bastard halibut(17.47%). 3. The results of comparative analysis and natural species and stocked species, in case of bastard halibut, jacopever species were occupied species(83.33~92%), weight(86.86~96%). The stocked species were occupied species of 8.00~16.67%, weight of 4.00~13.14%. Provided the stocked projets were enacted effectively in future. The density of dwelling of stocked species were increase. Also, it will be contribute to the increase of fishermens income.