• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.152-157
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• 1998

To analyze the role of the C and D domains in the cyclization activity of cyclodextrin glucanotransferase (CGTase), two plasmids, pKB1ΔC300 and pKB1ΔD96, were constructed in which DNA regions encoding 100 and 32 amino acids, respectively, from the C and D domains of B. stearothermophilus NO2 CGTase were deleted. The mutated CGTase from the pKBlΔC300 produced much lower amounts of ${\alpha}$-, ${\beta}$-, and $\gamma$-cyclodextrin (CD) than the parental CGTase. However, the mutated CGTase from the pKBlΔD96 showed a similar production pattern of CDs to wild-type CGTase. The production ratios of the ${\alpha}$-, ${\beta}$- and $\gamma$-CDs were not affected by the deletions, when compared to those of parental CGTase. The optimum temperature of the mutated CGTase from the pKBlΔC300 was decreased from $60^{\circ}C$ to $55^{\circ}C$. The optimum pH of the mutated CGTase from the pKB1D96 was shifted from 6.0 to 7.0. The thermostability of the two mutant CGTases were not changed. From these results, it is suggested that the C and D domains are not related to cyclization activity directly because mutant-enzymes deleted C or D domains still possessed their activity. However, they are important for other enzymatic properties such as productivity and pH optimum as a partition of CGTase tertiary structure.

• Korean Journal of Poultry Science
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• v.31 no.2
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• pp.73-78
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• 2004

The effect of supplemental yellow ${\beta}$-8-Apo-carotenoic acid ethyl ester (ACA) (0~300mg/kg feed) on its accumulation in each body part of laying hens and the pigmentation in egg yolk was determined. The chickens used in this study were 78-wk-old ISA brown laying hens. ACA significantly affected the color of the bodies of laying hens. The yellowness ($b^*$) but not the redness ($a^*$) and, the lightness ($L^*$) of the skin, and muscle as measured by a colorimeter significantly (P < 0.05) increased when ACA was fed at 50~100 mg/kg feed. Egg yolk color was also significantly affected by feeding ACA longer than 2 days (P < 0.05) at the levels higher than 50 mg/kg feed. Conclusively, ACA is recommended for improving yellowness of skin.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.7
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• pp.791-794
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• 2014

In this work, a 300 GHz imaging detector has been developed and image has been acquired in a 65-nm CMOS technology. The circuit was designed based on the square-law of MOSFET devices. The fabricated detector exhibits a maximum responsivity of 2,270 V/W and minimum NEP of $38pW/Hz^{1/2}$ at 285 GHz, and NEP< ${\sim}200pW/Hz^{1/2}$ for 250~305 GHz range. The chip size is $400{\mu}m{\times}450{\mu}m$ including the probing pads and a balun, while the core of the circuit occupies only $150{\mu}m{\times}100{\mu}m$.

• Journal of the Korean Magnetics Society
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• v.24 no.1
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• pp.18-21
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• 2014

The microwave absorption ($P_{tot}$), which is the double integration value of ferromagnetic resonance signal, propositional to the saturation magnetization, and the increase of the $P_{tot}$ measured during the thermal reaction time expect the growth process of the nanoparticles. Therefore, in this work, we measured the $P_{tot}$ in order to obtain the growth time of iron oxide nanoparticles after thermal decomposition of $Fe(acac)_3$ precursor at aging temperature $T_a=273$, 300 and $324^{\circ}C$, respectively. The best condition for monodisperse nanoparticles was obtained at $T_a=300^{\circ}C$, which condition showed the most rapid increase of $P_{tot}$ with thermal reaction time. Finally, the rapid growth rate was necessary condition for the synthesis of iron-oxide monodisperse nanoparticles.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.263-272
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• 2011

Highly luminescent and monodisperse InP quantum dots (QDs) were prepared by a non-organometallic approach in a non-coordinating solvent. Fatty acids with well-defined chain lengths as the ligand, a non coordinating solvent, and a thorough degassing process are all important factors for the formation of high quality InP QDs. By varying the molar concentration of indium to ligand, QDs of different size were prepared and their absorption and emission behaviors studied. By spin-coating a colloidal solution of InP QD onto a silicon wafer, InP QD thin films were obtained. The thickness of the thin films cured at 60 and $200^{\circ}C$ were nearly identical (approximately 860 nm), whereas at $300^{\circ}C$, the thickness of the thin film was found to be 760 nm. Different contrast regions (A, B, C) were observed in the TEM images, which were found to be unreacted precursors, InP QDs, and indium-rich phases, respectively, through EDX analysis. The optical properties of the thin films were measured at three different curing temperatures (60, 200, $300^{\circ}C$), which showed a blue shift with an increase in temperature. It was proposed that this blue shift may be due to a decrease in the core diameter of the InP QD by oxidation, as confirmed by the XPS studies. Oxidation also passivates the QD surface by reducing the amount of P dangling bonds, thereby increasing luminescence intensity. The dielectric properties of the thin films were also investigated by capacitance-voltage (C-V) measurements in a metal-insulator-semiconductor (MIS) device. At 60 and $300^{\circ}C$, negative flat band shifts (${\Delta}V_{fb}$) were observed, which were explained by the presence of P dangling bonds on the InP QD surface. At $300^{\circ}C$, clockwise hysteresis was observed due to trapping and detrapping of positive charges on the thin film, which was explained by proposing the existence of deep energy levels due to the indium-rich phases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.3
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• pp.321-327
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• 1989

The buffer activities of 72 species of natural pH adjusters in Chinese herb medicine materials of food materials by 100% acetic acid$({\mu}{\ell})$ titration until pH 4.0 in the $100m{\ell}$ of 1 % solution of the pH adjuster were evaluated for their abilities to retard acidification of Kimchi. There were 14 species above 100 of buffer activity such as Glycerehizae Radix(150), Siler divaricatum Benthan et Hooker etc. among selected Chinese herb medicine materials. In selected Chinese herb medicine materials, the buffer activities of Erillae Herba+Glycyrehizae Radix, Erillae Herba+Dioscoreae Rhizoma, Erillae Herba+Glycyrehizae Radix, Erillae Herba+Dioscoreae Rhizoma, Erillae Herba+Puerariae Radix, Chrysanthenum sinense+Puerariae Radix, Alismatis Rhizoma+Angelicae gigantis and Dioscoreae Rhizoma+Puerariae Radix were above 150 by same amount blending each other. Species and buffer activities of natural pH adjusters, which are higher buffer capabilities in mushroom, bean and vegetable classes were mungbean(207). soybean(160), pease(190), fungus(225), Garland chrysanthemum(200), amaranth(175), wild sesame leaf(200), parsley(202) and green pepper(257) etc. Species and buffer activities of higher buffer capabilities of natural pH adjusters of natural blending pH adjusters which is synergistic effect or natural blending pH adjusters which is synergistic effect mixing with radish juice were mung bean+peas(272), mung bean+soy bean(282), fungus+parsley(302), Garlan chrysanthenum+amaranth(300), Garland chrysanthenum+wild sesame leaf(277), amaranth+green pepper(300) and amaranthe+parsley(280) etc and those mixing with cabbage juice were peas+fungus(202), Garland chrysanthenum(207) and fungus+parsely (205) etc.

• Journal of the Korean Chemical Society
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• v.42 no.3
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• pp.277-284
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• 1998

Dendritic macromolecules of the first to fourth generation were synthesized, using alkenylation and hydrosilation cycles with allylmagnesium bromide and dichloromethylsilane as building blocks and siloxane tetramer $(Me(CH_2=CH)SiO)_4$, as core molecule. By the reaction of the dichloromethylsilyl-capped generation (G4P) with p-bromophenol, p-phenylphenol and lithium phenyethynylide, dendrimers with specific functions (G4P-BP (Mw: 16,300), G4P-PP (16,121), and CAP-PA (11,764)) have been produced. Analysis of new dendrimers by NMR, UV and MALD1 mass spectrometry suggests that they are pure and unified.

• Clinical and Experimental Reproductive Medicine
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• v.20 no.1
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• pp.65-70
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• 1993

To maintain a good sperm motility is one of the key factors for the successful artificial insemination in retrograde ejaculation, and the sperm motility has been shown to be affected by various environmental factors, including change in pH and osmolarity. Herein we have analyzed the effect of change in pH and osmolarity in urine and normal saline on sperm motility by Sperm Quality Analyzer and Makler counting chamber. Semen, which sampled by masturbation from a 28 year old male and showed normal finding on semen analysis, was used for this study. The results were as follows: 1. When osmolarity was fixed to 300mOsm, pH did not show a definite effect on the sperm moility. However, the motility was generally a bit better in alkaline urine and saline than in acid, particularly than in pH 5.0. 2. When pH was fixed to 7.5, sperm motility was best in urine and saline of 300mOsm. Hyperosmolarity had more adverse.effect on the motility than hypoosmolarity. 3. The sperm motility was worse in the urine than in saline under the same pH and osmolarity. In conclusion, osmolarity has a definite effect on sperm motility, where as pH has relatively little effect. And certain components of urine other than pH and osmolarity might affect the sperm motility.

• KSBB Journal
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• v.17 no.1
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• pp.14-19
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• 2002

The objective of this study is to investigate optimum condition for lignin peroxidase production by white rot fungi Phanerochaete chysosporium IFO 31249 immobilized in a rotating bioreactor. The maximum lignin peroxidase activity of batch culture in rotating bioreactor was 300 U/L. The optimum rotating speed and packing ratio of support for lignin peroxidase production in a rotating bioreactor were 1 rpm and 20%, respectively. The optimum concentration of $MnSO_4$$\cdot$$H_2O$ for manganese-dependent peroxidase production in a rotating bioreactor was 50 ppm. The sufficient supply of oxygen was the most important factor to achieve maximum lignin peroxidase production. It was possible to produce lignin peroxidase (LiP) and manganese-dependent peroxidase (MnP) for at least 3 times successive repeated-batch cultures, respectively.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.274-280
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• 2008

The study of subjects were 8 persons. The study measured VO2max of each person and substituted METs at exercise intensity of both VO2max 50% and VO2max 70% in accordance with energy consumption formula to set exercise time at energy consumption of both 300kcal and 600kcal. And, the study substituted inclination and rate at exercise intensity that was measured at preliminary test. T, B, NK cell varied depending upon aerobic exercise to have no significant difference of exercise intensity at relative ratio of T, B, NK lymphocyte of all of lymphocytes and to have significant difference of Expenditures Calorie (p<.01) and interaction (p<.05) by T cell and Expenditures Calorie (p<.01) by B cell and Expenditures Calorie (p <.001) and interaction (p<.05) by NK cell.