• Journal of Nutrition and Health
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• v.31 no.3
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• pp.271-278
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• 1998

Folate coenzymes are involved in one-carbon transfer reactions needed for the synthesis of nucleic acids, amino acids, and proteins which are very important for cell proliferation and differentiation. To investigate the effects of dietary folate content on plasma and tissue folate concentrations and on folate excretions in urine and feces, male Sprague-Dawley rats were raised for 4-10 weeks on semi-purified experimental diets containing 0mg, 2 mg, 8mg folate/kg diet. Folate concentrations were determined microbiologically using Lactobacillius casei (ATCC 7469). When compared to the folate adequate diet, the folate deficient diet decreased folate levels in plasma, liver and kidney , and the values were further decreased with experimental period. In rats reviving folate supplemented diets, plasma , liver and kidney folate adequate or supplemented diets, folate concentrations weer increased compared to animals on the folate adequate diet. In the folate adequate or supplemented diets, folate concentrations in the plasma and kidney were maintained at essentially the same level for 10 weeks . Folate concentrations in the liver, however, continued to increase with experimental period. Dietary folate intake seems to influence plasma and liver folate concentrations more than kidney folate concentrations. Folate excretions unrine and feces were significantly increased with dietary foalte intakes and experimental period. Folate excreted via urine was consideerably greater than that via feces. These resutls indicated that the foate supplemented diet improved plasma and tissue foalte status. Whether folate supplmentation improves foalte-dependent reactions remains to be researched.

• Journal of Nutrition and Health
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• v.32 no.2
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• pp.158-165
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• 1999

Effects of oral taurine supplementation (6g/day) on plasma concentration and urinary of free amino acids were evaluated in healthy female adults. Among twenty five female volunteers(23.6$\pm$0.3 years old) participated in the taurine supplementation program, twenty four subjects successfully completed the two supplementation program. Plasma and urinary levels of free amino acids were determined by using an automated amino acid analyzer based on ion-exchange chromatography. Two weeks of taurine supplementation resulted in a 65% increase in plasma taurine concentration (p<0.001), Changes in fasting plasma amino acid concentrations followed by taurine supplementation were not spectacular, and were all within the normal range for human aldults. Taurine supplementation significantly elevated urinary methionine, asparagine, hydorxyproline and phosphoserine excretions(31~280%), and significantly decreased the urinary excretions of isoleucine, glutamate and serine compared to the values prior to taurine supplementation. For almost every individual amino acids, 24 hr urinary excretion level was significantly correlated to the urinary excretion value expressed as nmol/mg creatinine(p<0.001). A significant negative correlation found between plasma glutamine concentration and urinary glutamine excretion level suggests that the decrease in plasma glutamine concentration might be associated with the enhanced glutamine excretion in urine followed by taurine supplementation.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.193-197
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• 2012

Oxygen plasma has been treated on the surface of indium-tin-oxide (ITO) to improve the efficiency of the organic light-emitting diodes (OLEDs) device. The plasma treatment was expected to inject the holes effectively due to the control of an ITO work-function and the reduction of surface roughness. To optimize the treatment condition, a surface resistance and morphology of the ITO surface were investigated. The effect on the electrical properties of the OLEDs was evaluated as a function of oxygen plasma powers (0, 200, 250, 300, and 450 W). The electrical properties of the devices were measured in a device structure of ITO/TPD/Alq3/BCP/LiF/Al. It was found the plasma treatment of the ITO surface affects on the efficiency of the device. The efficiency of the device was optimized at the plasma power of 250 W and decreased at higher power than 250 W. The maximum values of luminance, luminous power efficiency, and external quantum efficiency of the plasma treated devices increase by 1.4 times, 1.4 times, and 1.2 times, respectively, compared to those of the non-treated ones.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.379-381
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• 1998

An angiotensin converting enzyme (ACE) inhibitor was isolated and partially purified from bovine blood plasma. Bovine blood plasma was obtained after removing blood cells by centrifugation, followed by the addition of anticoagulant to whole bovine blood. To precipitate plasma proteins, bovine blood plasma was treated with 4% trichloroacetic acid (TCA) as a final concentration .An ACE inhibitor was isolated from TCA supernatnat, using ultrafiltration, gel permeation chormatography, and reverse-phase high pressure liquid chromatogrpahy. The ACE inhibitor purified from TCA supernatant had IC50 values of 9.4$\mu$M.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.1
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• pp.98-105
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• 2008

In this paper, the system for monitoring process of aluminum laser welding was developed using the light signal emitted from the plasma which comes from interaction between material and laser. Photodiode for monitoring system was selected based on the spectrum analysis of light from plasma and keyhole. Behavior of plasma and keyhole was analyzed through the sensor signals. Value of sensor signal represented the light intensity and fluctuation of signal indicated the stability of plasma and keyhole. For the relation between welding condition and sensor signals, the input power and weld geometry greatly effected on the average of each sensor signals. Using the feature values of signals, estimation model for tensile strength of weld was formulated with neural network algorithm. Performance of this model was verified through coefficient of determination and average error rate.

• Textile Coloration and Finishing
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• v.7 no.1
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• pp.1-9
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• 1995

In order to improve dyeability of poly(ethylene terephthalate)(PET) micro filament fabrics, the effect of the prior oxygen low temperature plasma on the subsequent dyeing(deep dyeing, printing) was examined in various conditions. The apparent concentration of dyed PET micro filament fabrics was increased by $O_{2}$plasma treatment. Higher discharge power levels and higher reactor pressure values created more significant effect. The wettability was significantly increased by $O_{2}$ plasma treatment. Therefore, it is predicted that introducing hydrophilic group on the surface of material can improve the apparent concentration of PET micro filament fabrics.

• Journal of the Korean Vacuum Society
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• v.7 no.1
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• pp.72-76
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• 1998

A new gas-flow type reactor for plasma polymerization was developed to synthesize functional polymers, which enhances reaction of radicals activated in the discharge. Styrene was used for the plasma polymerization and molecular strucure and molecular weight distribution of the plasma -polymerized styrene were studies. The ploymer was evaluated to be an efficient electron beam resist. The sensitivity of the plasma-polymerized styrene film formed by this new reactor was better than that of the reported values of conventional polystyrene, Fine resist patterns could be successfully developed by a wet process.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.12
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• pp.1880-1885
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• 2012

Nonlinear dynamical behaviors in thermionic low pressure discharge are investigated using a particle-in-cell(PIC) simulation. An electrostatic PIC code is developed to model the plasma discharge system including the kinetic effects. The elastic collision, excitation collision, ionization collision, and electron-ion recombination collision are considered in this code. The generated electrons and ions are traced to analyze physical characteristics of the plasma. The simulation results show that the nonlinear oscillation structures are observed for cold plasma in the system and the similar structures are observed for warm plasma with a shift in values of the bifurcation parameter. The detailed oscillation process can be subdivided into three distinct mode; anode-glow, temperature-limited, and double-layer modes.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.229-237
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• 2020

Background: We investigated the tolerability and pharmacokinetic properties of various ginsenosides, including Rb1, Rb2, Rc, Rd, and compound K, after single or multiple administrations of red ginseng extract in human beings. Methods: Red ginseng extract (dried ginseng > 60%) was administered once and repeatedly for 15 days to 15 healthy Korean people. After single and repeated administration of red ginsengextract, blood sample collection, measurement of blood pressure and body temperature, and routine laboratory test were conducted over 48-h test periods. Results: Repeated administration of high-dose red ginseng for 15 days was well tolerated and did not produce significant changes in body temperature or blood pressure. The plasma concentrations of Rb1, Rb2, and Rc were stable and showed similar area under the plasma concentration-time curve (AUC) values after 15 days of repeated administration. Their AUC values after repeated administration of red ginseng extract for 15 days accumulated 4.5- to 6.7-fold compared with single-dose AUC. However, the plasma concentrations of Rd and compound K showed large interindividual variations but correlated well between AUC of Rd and compound K. Compound K did not accumulate after 15 days of repeated administration of red ginseng extract. Conclusion: A good correlation between the AUC values of Rd and compound K might be the result of intestinal biotransformation of Rb1, Rb2, and Rc to Rd and subsequently to compound K, rather than the intestinal permeability of these ginsenosides. A strategy to increase biotransformation or reduce metabolic intersubject variability may increase the plasma concentrations of Rd and compound K.

• Journal of Powder Materials
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• v.28 no.4
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• pp.310-316
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• 2021

The effects of different spray angles (90°, 85°, 80°) on the microstructure and mechanical properties of a Y₂O₃ coating layer prepared using the atmospheric plasma spray (APS) process were studied. The powders employed in this study had a spherical shape and included a cubic Y₂O₃ phase. The APS coating layer exhibited the same phase as the powders. Thickness values of the coating layers were 90°: 203.7 ± 8.5 ㎛, 85°: 196.4 ± 9.6 ㎛, and 80°: 208.8 ± 10.2 ㎛, and it was confirmed that the effect of the spray angle on the thickness was insignificant. The porosities were measured as 90°: 3.9 ± 0.85%, 85°: 11.4 ± 2.3%, and 80°: 12.7 ± 0.5%, and the surface roughness values were 90°: 5.9 ± 0.3 ㎛, 85°: 8.5 ± 1.1 ㎛, and 80°: 8.5 ± 0.4 ㎛. As the spray angle decreased, the porosity increased, but the surface roughness did not show a significant difference. Vickers hardness measurements revealed values of 90°: 369.2 ± 22.3, 85°: 315.8 ± 31.4, and 80°: 267.1 ± 45.1 HV. It was found that under the condition of a 90° angle with the lowest porosity exhibited the best hardness value. Based on the aforementioned results, an improved method for the APS Y₂O₃ coating layer was also discussed.