• Progress in Superconductivity
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• 제14권1호
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• pp.30-33
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• 2012

We have grown $MgB_2$ superconducting thin films on the SiC buffer layers by means of hybrid physical-chemical vapor deposition (HPCVD) technique. Prior to that, SiC was first deposited on $Al_2O_3$ substrates at various temperatures from room temperature to $600^{\circ}C$ by using the pulsed laser deposition (PLD) method in a vacuum atmosphere of ${\sim}10^{-6}$ Torr pressure. All samples showed a high transition temperature of ~40 K. The grain boundaries of $MgB_2$ samples with SiC layer are greater in amount, compare to that of the pure $MgB_2$ samples. $MgB_2$ with SiC buffer layer samples show interesting change in the critical current density ($J_c$) values. Generally, at both 5 K and 20 K measurements, at lower magnetic field, all $MgB_2$ films deposited on SiC buffer layers have low $J_c$ values, but when they reach higher magnetic fields of nearly 3.5 Tesla, $J_c$ values are enhanced. $MgB_2$ film with SiC grown at $600^{\circ}C$ has the highest $J_c$ enhancement at higher magnetic fields, while all SiC buffer layer samples exhibit higher $J_c$ values than that of the pure $MgB_2$ films. A change in the grain boundary morphologies of $MgB_2$ films due to SiC buffer layer seems to be responsible for $J_c$ enhancements at high magnetic fields.

• 한국식생활문화학회지
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• 제15권4호
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• pp.253-258
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• 2000

국내에서 버려지는 쌀눈활용을 위한 기초연구로 쌀눈의 화삭성분들을 분석하였다. 일반성분은 수분 8.69%, 조지방 21.18%, 조단백질 16.50%, 조섬유 2.95%, 조회분 6.23%, 그리고 당질함량은 44.45%로 나타났다. 유리당은 maltose, glucose, fructose가 있었으며 각각 569.00, 68.80, 50.20mg/100g함유되어 있었다. 아미노산함량은 글루탐산이 1920.09mg/100g, 아르기닌이 15.03mg/100g, 아스파르트산이 1208.7mg/100g, 알라닌이 1001.2mg/100g으로 가장 많이 함유되어 있었으며, 함황아미노산인 시스틴과 메티오닌은 적었다. 무기질 조성은 8종류의 무기성분들이 검출되었으며 칼륨과 인이 각각 가장 많은 1217.80, 1766.22mg/100g이었으며 칼슘, 망감, 나트륨이 각각 36.60, 16.74, 16.22mg/100g으로 많았으며, 아연, 철, 구리도 각각 11.75, 7.99, 1.16mg/100g이 들어 이었다. 비타민함량은 5가지의 수용성 비타민과 지용성비타민이 토코페롤이 함유되어 있었으며, 비타민 E가 11.96mg/100g으로 가장 많았고 $B_1$과 $B_2$는 각각 5.69mg/100g, 0.45mg/100g였으며 비타민 C는 1.66mg/100g 그리고 나이아신과 비타민 $B_6$는 각각 2.96mg/100g, 0.69mg/100g였다. 지방산은 6가지 종류의 지방산이 함유되어 있었으며, 주지방산은 linoleic acid와 oleic acid로 전체지방산의 약 64%를 차지하고 있다. 또한 모든 유지류에 널리 분포되어 있는 palmitic acid가 22.2%였으며, arachidic acid도 3.1%였다. 16종의 flavonoid와 9종의 phenolic acid를 screening한 결과 쌀눈에서는 검출되지 않았다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1420-1421
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• 2006

In this study, structural and micowave dielectric properties of the $Mg_{5}B_{4}O_{15}$ (B=Ta, Nb) cation-deficient perovskite ceeramics. The specimens are prepared through the solid-state route. According to the XRD pattern, $Mg_{4}Ta_{2}O_9$ and $MgTa_{2}O_6$ phase exist in calcined and sintered $Mg_{5}Ta_{4}O_{15}$ powder. Also $Mg_{5}Ta_{4}O_{15}$ phase added with increasing sintering temperature. In the case of calcined and sintered $Mg_{5}Nb_{4}O_{15}$ powder, single phase of $Mg_{5}Nb_{4}O_{15}$ were appeared. The bulk density and quality factor of the $Mg_{5}B_{4}O_{15}$ (B=Ta, Nb) ceramics were increased with sinteming temperature in $1400^{\circ}C{\sim}1450^{\circ}C$, but these were decreased in another sintering temperature. Dielectric constant of the $Mg_{5}Ta_{4}O_{15}$ ceramics was increased continuously with increasing of sintering temperature. And the dielectric constant of the $Mg_{5}Nb_{4}O_{15}$ ceramics was increased in $1400^{\circ}C{\sim}1450^{\circ}C$ but decreased in $1475^{\circ}C$. In the case of the $Mg_{5}Ta_{4}O_{15}$ and $Mg_{5}Nb_{4}O_{15}$ ceramics sintered at $1450^{\circ}C$ for 5h, the dielectric constant, quality factor, and temperature coefficient of the resonant frequency (TCRF) were 8.2, 259,473 GHz, -10.91 $ppm/^{\circ}C$ and 14, 37,350 GHz, -52.3 $ppm/^{\circ}C$, respectively.

• 한국가축번식학회지
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• 제20권2호
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• pp.197-205
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• 1996

This study was conducted to examine the effect of sustained release recombinant bovine somatotropin(SR-rBST) with different dosage(0, 0.03mg/kg body weight/14 day, 0.06mg/kg body weight/14 day, 0.09mg/kg body weight/14 day) on the economical traits of the semen characteristics and sexual behaviors and blood chemical values with sixteen Holstein dairy young bulls in Dairy Cattle Improvement Center of National Livestock Co-operatives Federation. Sensual testings of collected semens of Holstein young bulls were not different among treatments (p>0.05). Ejaculated semen volumes of control, SR-rBST 0.03mg, 0.06mg and 0.09mg groups were 5.6ml, 5.6ml, 6.0ml and 6.7m, respectively, but the result of SR-rBST 0.09mg group significantly increased semen volume(P<0.05). In sperm concentration, SR-rBST 0.06mg and 0.09mg groups significantly increased the total number of sperms than the other groups(P<0.05). In otherwise, SR-rBST treatments did not affect on pH, osmotic pressure, anti forzen rate, abnormality and motility of collected semen during whole experimental period. Reaction time(RT), sexual aggressiveness(SA) and tactile stimulation(TS) were not different among treatments. The libido scores(LS) of control, 0.03mg, 0.06mg and 0.09mg groups were 68.0, 80.5, 73.9 and 80.8, respectively, and LS were significantly improved by SR-rBST administration(P<0.05). The effect of SR-rBST on scrotal circumference measurement that is important factor to determine the ability of semen production, was not different among treatments. These studies indicates that SR-rBST treatments favourably affect on semen quality and sexual libido in Holstein young bull.

• 치과방사선
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• 제24권2호
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• pp.249-260
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• 1994

The purpose of this study was to aid in the radiation therapy of head and neck cancer patients. For this study, radiation survival curves were generated for Bl6, MG-63 and YAC-l cell lines using semiautomated MTT assay and Dye Exclusion Assay. Irradiation of 2, 4, 6, 8, 10Gy were delivered at room temperature at a dose rate of 210.2cGy/min using / sup 60/Co γ-ray Irradiator ALOORAOO 8. The viable cells were determined for each radiation dose and compared to control values. The obtained results were as follows: 1. There was significantly different absorbance at 10Gy on B16 cell line in MTT assay(P<0.05). 2. There was significantly different absorbance at 4, 6, 8, 10Gy on MG-63 cell line in MTT assay(P<0.05). 3. YAC-l cell line was more sensitive than B16 or MG-63 cell line to all doses of radiation(P<0.05). 4. There was significantly different absorbance among all tumor cell lines except between B16 and MG-63 cell line at ZGy in MTT assay(P<0.05). 5. Good correlation was obtained between MTT assay and DEA(P<0.05). The efficient of correlation of B16, MG-63 and YAC-l cell line was 0.845, 0.824 and 0.906, respectively.

• Nutrition Research and Practice
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• 제8권6호
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• pp.688-694
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• 2014

BACKGROUND/OBJECTIVES: Recent research regarding vitamin $B_6$ status including biochemical index is limited. Thus, this study estimated intakes and major food sources of vitamin $B_6$; determined plasma pyridoxal 5'-phosphate (PLP); and assessed vitamin $B_6$ status of Korean adults. MATERIALS/METHODS: Three consecutive 24-h diet recalls and fasting blood samples were collected from healthy 20- to 64-year-old adults (n = 254) living in the Seoul metropolitan area, cities of Kwangju and Gumi, Korea. Vitamin $B_6$ intake and plasma PLP were analyzed by gender and by vitamin $B_6$ supplementation. Pearson's correlation coefficient was used to determine associations of vitamin $B_6$ intake and plasma PLP. RESULTS: The mean dietary and total (dietary plus supplemental) vitamin $B_6$ intake was $1.94{\pm}0.64$ and $2.41{\pm}1.45mg/day$, respectively. Median (50th percentile) dietary intake of men and women was 2.062 and 1.706 mg/day. Foods from plant sources provided 70.61% of dietary vitamin $B_6$ intake. Only 6.3% of subjects consumed total vitamin $B_6$ less than Estimated Average Requirements. Plasma PLP concentration of all subjects was $40.03{\pm}23.71nmol/L$. The concentration of users of vitamin $B_6$ supplements was significantly higher than that of nonusers (P < 0.001). Approximately 16% of Korean adults had PLP levels < 20 nmol/L, indicating a biochemical deficiency of vitamin $B_6$, while 19.7% had marginal vitamin $B_6$ status. Plasma PLP concentration showed positive correlation with total vitamin $B_6$ intake (r = 0.40984, P < 0.0001). CONCLUSIONS: In this study, vitamin $B_6$ intake of Korean adults was generally adequate. However, one-third of subjects had vitamin $B_6$ deficiency or marginal status. Therefore, in some adults in Korea, consumption of vitamin $B_6$-rich food sources should be encouraged.

• Journal of Plant Biotechnology
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• 제43권4호
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• pp.492-499
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• 2016

본 연구는 육종용을 이용한 기능성 화장품 소재 개발을 목적으로 육종용 추출물의 피부 미백 및 항노화 효능 검정을 위해 수행되었다. 육종용 추출물의 세포 생존율은 B16F10 melanoma 세포를 이용하여 MTT assay를 수행하여 측정한 결과, 육종용 추출물 4 mg/ml 농도에서 90% 이상의 세포 생존율을 보였다. 육종용 추출물을 처리한 B16F10 melanoma 세포를 이용하여 RT-PCR로 유전자 발현을 검정한 결과 tyrosinase, collagenase 및 elastase 유전자의 발현을 육종용 추출물 4 mg/ml 농도에서 각각 80.9%, 37.6%, 70.9% 억제 하였다. 육종용 추출물의 DPPH 라디칼 소거능 측정을 이용한 항산화 활성은 2 ~ 10 mg/ml 농도에서 70.6% ~ 82.6%로 높게 나타났다. 육종용 추출물의 미백과 항노화 효과를 검정하기 위하여 육종용 추출물을 2, 4, 6, 8 및 10 mg/ml 농도로 처리하여 확인하였다. 육종용 추출물의 tyrosinase 저해활성은 66.8% ~ 78.5%, elastase 저해활성은 67.6% ~ 79.3%, collagenase 저해활성은 72.3% ~ 83.6%로 각각 나타났으며, hyaluronidase 저해활성은 65.8% ~ 69.2%로 나타났다. 따라서 육종용은 피부 미백 및 노화방지를 위한 기능성 화장품 소재로 우수한 것으로 평가되며, 세포생존율과 각종 효능을 고려할 때, 육종용 추출물 4 mg/ml 농도가 적정농도로 판단된다.

• 한국약용작물학회지
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• 제12권4호
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• pp.304-308
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• 2004

St. John's Wort의 정상세포에 대한 세포독성을 측정한 결과 두 종류의 추출물 모두 1.0 mg/ml의 높은 농도에서도 정상세포 생존율을 80% 이상으로 유지시켜 정상세포의 안전성이 유지되었다. St. John s wort 추출물은 0.5 mg/ml의 농도에서 간암세포주인 Hep3B에 대하여 80% 이상의 높은 억제율을 나타내었으며, 위암세포주인 AGS에 대하여서는 75% 이상의 높은 생육억제율을 나타내었고, 유방암세포주인 MCF-7에 대하여서는 증류수 추출물들은 0.5 mg/ml 이상의 농도에서 약 80%정도, 에탄올 추출물들은 90% 이상의 매우 높은 암세포 생육억제활성을 나타내었다. 또한 각 추출물의 정상세포독성에 대한 암세포의 억제율을 나타내는 selectivity에 있어서 각 추출물이 4이상의 수치를 나타내어, 암세포를 선택적으로 사멸하는 기작을 지닌 것을 확인하였다. 고추나물의 뿌리 물 추출물들은 인간 B와 T 세포주의 생육을 0.5 mg/ml 이상의 농도에서 T세포의 생장을 2배 이상, B-cell의 경우 $1.2{\sim}1.5$배 이상의 생육 증가를 나타내었으며, 물 추출물들이 에탄올 추출물에 비하여 높은 면역세포의 생육 증진활성을 나타내었다. 배양기간에 따른 면역세포의 생육과 면역물질인 cytokine의 생산을 보면 배양 5일째 두 종류 추출물에서 가장 높은 생존율을 나타내었으며 추출물을 첨가하지 않은 경우에 비교하여 약 1.5배의 생장율을 나타내었고, B 세포에서 IL-6은 에탄올 추출물이 배양 5일째 0.5 mg/ml의 농도에서 최고 6.9 pg/cell의 분비량을 나타내었고, T 세포의 $TNF-{\alpha}$도 에탄올 추출물이 배양 6일째 최고 6.8 pg/cell의 분비량을 나타내었다.

• 한국산림과학회지
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• 제97권3호
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• pp.249-254
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• 2008

생물반응기를 이용한 가시오갈피 부정근 배양시에 jasmonic acid를 농도별 (0, 0.01, 0.05, 0.1, 03, 0.5 mg/L)로 처리하여 부정근의 생장과 eleutheroside류 생산과의 관계를 조사하였다. Jasmonic acid 처리농도별 부정근의 생장은 무처리구에서 4.6 g Dry weight (DW)/L로 가장 높았으며 jasmonic acid 농도가 증가할수록 부정근 생장은 감소하였다. 그러나 eleutheroside B와 E의 함량은 jasmonic acid 농도가 높을수록 증가하여 0.5 mg/L 처리구에서 각각 $476.3{\mu}g/g\;DW$, $676.0{\mu}g/g\;DW$로 생산량이 가장 많았다. 반면에 eleutheroside $E_1$은 0.01 mg/L 처리구에서 $46.1{\mu}g/g\;DW$로 생산량이 가장 많았다. 배지 1L당 eleutheroside류의 총생산량은 0.01 mg/L 처리구에서 $2468.6{\mu}g/L$를 생산하여 가장 우수하였다. 0.1 mg/L의 jasmonic acid 처리 후 10일간 eleutheroside류의 함량을 조사한 결과 eleutheroside B는 jasmonic acid처리 후 6일째, eleutheroside E는 처리 후 8일째, eleutheroside $E_1$은 처리 후 4일째 각각 가장 많은 생산량을 보여 주었다.

• 한국세라믹학회지
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• 제42권9호
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• pp.607-612
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• 2005

The effect of MgO diluents in combustion synthesis of $TiB_2$ nano particles was investigated. The reaction $TiO_2\;+\;B_2O_3\;+\;xMg\;{\rightarrow}\;TiB_2\;+\;5MgO$ was used to synthesize $TiB_2$ nano particles. The combustion velocity was measured to examine the relation between the reaction temperature and the morphologies of particles. The diluent MgO did not react with the reactants and played a role to decrease combustion temperature. As the MgO diluents contents increased, the particles with the smaller size and the narrower size distribution were synthesized. At the condition of 6 mole of MgO, the combustion wave velocity was about 5 cm/see and the synthesized particles showed the size of 60 nm with narrow size distribution.