• Journal of Life Science
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• v.29 no.3
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• pp.376-381
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• 2019

To construct useful yeast strain for bioethanol production, we improved yeast harboring various phenotypes by using yeast protoplast fusion method. In this study, S. cerevisiae BYK-F11 strain which have ethanol tolerance, thermotolerance and ${\beta}-glucanase$ activity and P. $stipitis{\Delta}ura$ strain which has xylose metabolism pathway were fused by genome shuffling. P. $stipitis{\Delta}ura$ strain was constructed for protoplast fusion by URA3 gene disruption, resulting in uracil auxotroph. By protoplast fusion, several fused cells were selected and BYKPS-F8 strain (fused cell) showing both karyotypes from two parent strains (S. cerevisiae BYK-F11 and P. $stipitis{\Delta}ura$ strain) among 22 fused cells was finally selected. Sequentially, various phenotypes such as ${\beta}-glucanase$ activity, xylose utility, ethanol tolerance, thermotolerance and ethanol productivity were analyzed. The BYKPS-F8 strain obtained ${\beta}-glucanase$ activity from BYK-F11 strain and 1.2 fold increased xylose utility from P. $stipitis{\Delta}ura$ strain. Also, the BYKPS-F8 strain showed thermotolerance at $40^{\circ}C$ and increased ethanol tolerance in medium containing 8% ethanol. In this fused cell, 7.5 g/l ethanol from 20 g/l xylose was produced and the multiple phenotypes were stably remained during long term cultivation (260 hr). It was proved that novel biological system (yeast strains) is easily and efficiently bred by protoplast fusion among yeasts having different genus.

• Journal of Acupuncture Research
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• v.21 no.4
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• pp.135-147
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• 2004

Objective: Moxibustion is one of major healing technique in oriental medicine. It has been widely used in many disease. There is an text which suggest moxibustion is more efficient to the situation of han(寒) and heo(虛) than yeal(熱) and sil(實) in Huangdineijing <黃帝內經>. The aim of this study is to research the effect of moxibustion at Shinmun(H7) is different according to cold or heat tendendy man by analyzing the electroencephalogram(EEG). Methods: We classified objects by their cold or heat tendency using questionnare for cold - heat patternization. (12 cold tendency man, 19 heat tendency man) Before and after moxibustion at Shinmun(H7), EEG raw data were measured during 5 minutes. The correlation dimension(D2), the correlation dimension variability rate(${\Delta}D2$), largest lyapunov exponent(L1) and largest lyapunov exponent variability rate(${\Delta}L1$) were calculated. We analyzed D2, ${\Delta}D2$, L1, ${\Delta}L1$ to see the effect of moxibustion at Shinmun(H7) was statistically different according to Cold or Heat tendendy man. Results : Paired t-test showed significant differences between before and after moxibustion at Shinmun(H7) on the Fp2 in D2(p<0.05), on the Fp2, F3 and F4 in ${\Delta}L1$(p<0.05). Student Hest showed significant differences between cold and heat tendendy man on the F3 in ${\Delta}L1$(p<0.05). Conclusion: These results suggest that moxibustion at Shinmun has an effect on stabilizing mind and it is more efficient to the cold tendendy man than the heat tendendy man.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.233-237
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• 2008

The essential oil was obtained from the aerial part of Rhododendon mucronulatum Turcz. var. ciliatum Nakai by steam distillation, samples were collected by headspace (HS) and solid-phase microextraction (SPME) methods, and the compositions of the oil were analyzed by gas chromatography-mass spectrometry (GC-MS). Nineteen constituents were identified from the essential oil: 15 carbohydrates, 3 alcohols, and 1 acetates. Major constituents were 2-${\beta}$-pinene (16.1%), camphene (11.9%), ${\delta}$-3-carene (11.4%), d,l-limonene (9.5%), and ${\gamma}$-terpinene (9.5%). By SPME extraction, seventeen constituents were identified: 13 hydrocarbons, 1 alcohol, 1 nitrogen-containing compound, 1 acetate, and 1 amine. Major constituents of the SPME-extracted sample were cam phene (19.6%), 2-${\beta}$-pinene (18.0%), ${\delta}$-3-carene (17.4%), trimethyl hydrazine (9.7%), ${\gamma}$-terpinene (8.5%), and d,l-limonene (5.5%). By HS extraction, thirteen constituents were identified: 11 hydrocarbons, 1 alcohol, and 1 nitrogen-containing compound. Major constituents of the HS-extracted sample were camphene (25.8%), ${\delta}$-3-carene (24.8%), 2-${\beta}$-pinene (20.2%), d,l-limonene (5.4%), tricyclene (5.1%) and trimethyl hydrazine (4.6%). The fragrance of the essential oil was coniferous, balsamic, and woody, and the $IC_{50}$ value of the essential oil was 0.030 ${\mu}g/mg$ in MTT assay using UaCaT keratinocyte cell line.

• Journal of Korean Dental Science
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• v.8 no.2
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• pp.49-56
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• 2015

Purpose: The effect of accelerated aging on color stability of various dual-cured self-adhesive resin cements were evaluated in this study. Materials and Methods: Color stability was examined using three different brands of dual-cured self-adhesive resin cements: G-CEM LinkAce (GC America), MaxCem Elite (Kerr), and PermaCem 2.0 (DMG) with the equivalent color shade. Each resin cement was filled with Teflon mold which has 6 mm diameter and 2 mm thickness. Each specimen was light cured for 20 seconds using light emitting diode (LED) light curing unit. In order to evaluate the effect of accelerated aging on color stability, color parameters (Commission Internationale de l'Eclairage, CIE $L^*$, $a^*$, $b^*$) and color differences (${\Delta}E^*$) were measured at three times: immediately, after 24 hours, and after thermocycling. The $L^*$, $a^*$, $b^*$ values were analyzed using Friedman test and ${\Delta}E^*$ values on the effect of 24 hours and accelerated aging were analyzed using t-test. These values were compared with the limit value of color difference (${\Delta}E^*=3.7$) for dental restoration. One-way ANOVA and Scheff's test (P<0.05) were performed to analyze each ${\Delta}E^*$ values between cements at each test period. Result: There was statistically significant difference in comparison of color specification ($L^*$, $a^*$, $b^*$) values after accelerated aging except $L^*$ value of G-CEM LinkAce (P<0.05). After 24 hours, color difference (${\Delta}E^*$) values were ranged from 2.47 to 3.48 and $L^*$ values decreased and $b^*$ values increased in all types of cement and MaxCem Elite had high color stability (P<0.05). After thermocycling, color change's tendency of cement was varied and color difference (${\Delta}E^*$) values were ranged from 0.82 to 2.87 and G-CEM LinkAce had high color stability (P<0.05). Conclusion: Color stability of dual-cured self-adhesive resin cements after accelerated aging was evaluated and statistically significant color changes occurred within clinically acceptable range.

• Korean Journal of Materials Research
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• v.15 no.11
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• pp.722-729
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• 2005

The electrical and dielectric stability of zinc oxide-based varistors were investigated with the cobalt oxide contents in the range of $0.5\~5.0 mo\l%$. As cobalt oxide contents increased, the ceramic density increased in the range of $5.25\~5.55g/cm^3$ and the varistor voltage decreased in the range of $235.3\~86.0V$. The varistor with on addition of cobalt oxide $1.0 mol\%$ exhibited good nonlinearity. in which the nonlinear exponent is 66.6 and the leakage current is $1.2{\mu}A$. Furthermore, the varistors exhibited the highest electrical and dielectric stability, with $\%{\Delta}V_{1mA}=-1.9\%,\;\%{\Delta}{\alpha}=-10.5\%,\;\%{\Delta}I_L=+275.0\%,\;and\;\%{\Delta}tna{\delta}=+55.6\%$, under DC accelerated aging $0.95V_{1mA}/150^{\circ}C/24h$.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.575-580
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• 1999

In this study, the quality changes of Hoelen was investigated, which were color differences, browning degrees, total phenolic compounds and electron donating abilities to optimize drying condition using hot air and far infrared drying by changing conditions such as temperatures, air velocities and radiation distances. In color values, ${\Delta}b\;value$ decreased with increasing temperatures, while ${\Delta}L$, ${\Delta}a$ and ${\Delta}E\;value$ increased. The browning degrees showed the similar tendency with the color values. Total phenolic components of Hoelen decreased with increasing drying temperature and air velocity, and decreasing radiation distance. On the other hand, there was no significant difference in the changes of electron donating abilities (EDA) of Hoelen among drying methods and conditions. As a result, the hot air drying was more effective method than the far infrared was.

• Wind and Structures
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• v.31 no.3
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• pp.229-240
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• 2020

In the present work, the main features of primary vortices and the vorticity concentrations downstream of vortex bursting in crossflow plane of a delta wing with a sweep angle of Λ=70° were investigated under the variation of the sideslip angles, β. For the pre-review of flow structures, dye visualization was conducted. In connection with a qualitative observation, a quantitative flow analysis was performed by employing Particle Image Velocimetry (PIV). The sideslip angles, β were varied with four different angles, such as 0°, 4°, 12°, and 20° while angles of attack, α were altered between 25° and 35°. This study mainly focused on the instantaneous flow features sequentially located at different crossflow planes such as x/C=0.6, 0.8 and 1.0. As a summary, time-averaged and instantaneous non-uniformity of turbulent flow structures are altered considerably resulting in non-homogeneous delta wing surface loading as a function of the sideslip angle. The vortex bursting location on the windward side of the delta wing advances towards the leading-edge point of the delta wing. The trajectory of the primary vortex on the leeward side slides towards sideways along the span of the delta wing. Besides, the uniformity of the lift coefficient, C_L over the delta wing plane was severely affected due to unbalanced distribution of buffet loading over the same plane caused by the variation of the sideslip angle, β. Consequently, dissimilarities of the leading-edge vortices result in deterioration of the mean value of the lift coefficient, C_L.

• The Journal of Advanced Prosthodontics
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• v.6 no.6
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• pp.427-433
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• 2014

PURPOSE. Surface color is one of the main criteria to obtain an ideal esthetic. Many factors such as the type of the material, surface specifications, number of firings, firing temperature and thickness of the porcelain are all important to provide an unchanged surface color in dental ceramics. The aim of this study was to evaluate the color changes in dental ceramics according to the material type and glazing methods, during the multiple firings. MATERIALS AND METHODS. Three different types of dental ceramics (IPS Classical metal ceramic, Empress Esthetic and Empress 2 ceramics) were used in the study. Porcelains were evaluated under five main groups according to glaze and natural glaze methods. Color changes (${\Delta}E$) and changes in color parameters (${\Delta}L$, ${\Delta}a$, ${\Delta}b$) were determined using colorimeter during the control, the first, third, fifth, and seventh firings. The statistical analysis of the results was performed using ANOVA and Tukey test. RESULTS. The color changes which occurred upon material-method-firing interaction were statistically significant (P<.05). ${\Delta}E$, ${\Delta}L$, ${\Delta}a$ and ${\Delta}b$ values also demonstrated a negative trend. The MC-G group was less affected in terms of color changes compared to other groups. In all-ceramic specimens, the surface color was significantly affected by multiple firings. CONCLUSION. Firing detrimentally affected the structure of the porcelain surface and hence caused fading of the color and prominence of yellow and red characters. Compressible all-ceramics were remarkably affected by repeated firings due to their crystalline structure.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.3
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• pp.503-515
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• 2018

In this research, the three-dimensional structural and colorimetrical modeling of yarn-dyed woven fabrics was conducted based on the Kubelka-Munk theory (K-M theory) for their accurate color predictions. In the K-M theory for textile color formulation, the absorption and scattering coefficients, denoted K and S, respectively, of a colored fabric are represented using those of the individual colorants or color components used. One-hundred forty woven fabric samples were produced in a wide range of structures and colors using red, yellow, green, and blue yarns. Through the optimization of previous two-dimensional color prediction models by considering the key three-dimensional structural parameters of woven fabrics, three three-dimensional K/S-based color prediction models, that is, linear K/S, linear log K/S, and exponential K/S models, were developed. To evaluate the performance of the three-dimensional color prediction models, the color differences, ${\Delta}L^*$, ${\Delta}C^*$, ${\Delta}h^{\circ}$, and ${\Delta}E_{CMC(2:1)}$, between the predicted and the measured colors of the samples were calculated as error values and then compared with those of previous two-dimensional models. As a result, three-dimensional models have proved to be of substantially higher predictive accuracy than two-dimensional models in all lightness, chroma, and hue predictions with much lower ${\Delta}L^*$, ${\Delta}C^*$, ${\Delta}h^{\circ}$, and the resultant ${\Delta}E_{CMC(2:1)}$ values.

• Applied Biological Chemistry
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• v.35 no.3
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• pp.210-217
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• 1992

A photosynthetic bacterium strain KUP-74 producing high amount of S-amino-levulinic acid(ALA) was isolated from soils, which was identified as Rhodocyclus gelatinosus. After 10 days cultivation under anaerobic-light condition at $30^{\circ}C$, 4 Klux and pH 6.8, 5 mg/l of ALA was formed extracellularly. ALA productions were increased up to 8 mg/l and 12 mg/l in cell cultivations either by the addition of 0.5% glycerol (v/v) or 10 mM of glycine and succinic acid, respectively, using Lascelles basal medium eliminated L-glutamic acid. By cultivation in the presence of 30 mM each D,L-glutamic acids and D,L-glutamines the yield of ALA showing a late induction phenomenon was reached the maximum value of 21 mg/l. Different culture times were needed to generate maximum ALA yields by the addition of initial precursors of $C_4$ and $C_5$ pathways in basal medium, as being 107 h and 262 h, respectively. 40 mg/l yield of ALA was observed by cell cultivation with the basal medium containing each 10 mM levulinic acid(LA) and glycine simultaneously.