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Gemological Characterization of B. C. Jade (비씨 제이드의 보석학적 연구)

  • Kim, Won-Sa;Wight, Willow
    • Journal of the Mineralogical Society of Korea
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    • v.21 no.2
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    • pp.177-182
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    • 2008
  • The Gemological characteristics of B.C. jade from Cassiar Mine, British Colombia, Canada, have been investigated, using polarizing microscopy, Mohs' hardness, refractive index and density measurements, X-ray powder diffraction, X-ray fluorescence spectrometry, ICP-MS, Infrared absorption spectrometry, and DTA/TGA. The B.C. jade is deeply green (spinach peen or olive green) in color and is translucent. It shows a resinous or waxy luster. The principal mineral of the material is tremolite-actinolite solid solution and minor amount of Cr-garnet and unidentified opaque minerals are accompanied. Mohs' hardness value ($5.5{\sim}6$). refractive index (1.62), and specific gravity (3.01) are measured. It is very highly tough and shows hackly fracture. The high Fe content ($Fe_2O_3\;4.14{\sim}4.66\;wt%$) in B.C. jade is attributable to a deepening of green color of the material. The B.C. jade starts to dehydrate at v and dehydration is completed at $1000.8^{\circ}C$, transforming tremolite-actinolite solid solution to enstatite, diopside, quartz, and water in its place. This possible reaction is supported by the weight loss of B.C. jade (1.93 wt%) at $1000.8^{\circ}C$ indicated by TGA curve.

The Promotive Effects of Antioxidative Apigenin on the Bioavailability of Paclitaxel for Oral Delivery in Rats

  • Choi, Sang-Joon;Choi, Jun-Shik
    • Biomolecules & Therapeutics
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    • v.18 no.4
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    • pp.469-476
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    • 2010
  • This study was to investigate the effect of apigenin on the bioavailability of paclitaxel after oral and intravenous administration in rats. The effect of apigenin on P-glycoprotein (P-gp), cytochrome P450 (CYP)3A4 activity was evaluated. The pharmacokinetic parameters of paclitaxel were determined in rats after oral (40 mg/kg) or intravenous (5 mg/kg) administration of paclitaxel with apigenin (0.4, 2 and 8 mg/kg) to rats. Apigenin inhibited CYP3A4 activity with 50% inhibition concentration ($IC_{50}$) of 1.8 ${\mu}M$. In addition, apigenin significantly inhibited P-gp activity. Compared to the control group, apigenin significantly increased the area under the plasma concentration-time curve (AUC, p<0.05 by 2 mg/kg, 59.0% higher; p<0.01 by 8 mg/kg, 87% higher) of oral paclitaxel. Apigenin also significantly (p<0.05 by 2 mg/kg, 37.2% higher; p<0.01 by 8 mg/kg, 59.3% higher) increased the peak plasma concentration ($C_{max}$) of oral paclitaxel. Apigenin significantly increased the terminal half-life ($t_{1/2}$, p<0.05 by 8 mg/kg, 34.5%) of oral paclitaxel. Consequently, the absolute bioavailability (A.B.) of paclitaxel was significantly (p<0.05 by 2 mg/kg, p<0.01 by 8 mg/kg) increased by apigenin compared to that in the control group, and the relative bioavailability (R.B.) of oral paclitaxel was increased by 1.14- to 1.87-fold. The pharmacokinetics of intravenous paclitaxel were not affected by the concurrent use of apigenin in contrast to the oral administration of paclitaxel. Accordingly, the enhanced oral bioavailability by apigenin may be mainly due to increased intestinal absorption caused via P-gp inhibition by apigenin rather than to reduced renal and hepatic elimination of paclitaxel. The increase in the oral bioavailability might be mainly attributed to enhanced absorption in the gastrointestinal tract via the inhibition of P-gp and reduced first-pass metabolism of paclitaxel via the inhibition of the CYP3A subfamily in the small intestine and/or in the liver by apigenin. It appears that the development of oral paclitaxel preparations as a combination therapy is possible, which will be more convenient than the i.v. dosage form.

Analysis of dose from surface to near the buildup region in the therapeutic X-ray beam (표피로 부터 buildup 영역까지 흡수되는 암치료용 방사선의 선량분석)

  • Vahc, Young-Woo
    • Progress in Medical Physics
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    • v.6 no.2
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    • pp.41-50
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    • 1995
  • The absorbed dose and contaminant electron distribution of therapeutic X-ray beam (15MV photon) was studied with a half blocked beams of 30$\times$30$\textrm{cm}^2$ and field size ranging from 5$\times$5 to 30$\times$30$\textrm{cm}^2$. For a 15MV photon beam energy, the value of the depth of dose maximum, d$_{max}$, gradually decrease with increasing field size from 5$\times$5 to 30$\times$30$\textrm{cm}^2$ due to mainly by contaminant electrons which are produced in the flattening filter and scattered by collimator jaws, tray holder〔Lucite〕, blocking block and air. The results suggest that separate dosimetry data should be kept for blocked and unblocked field. The inherence of the contaminant electrons to the open field depth of maximum dose can lead to mistaken results if attenuation measurements are made at that depth. A nurmerous contaminant electrons mainly were distributed as shape of corn in the central photon beam and their path length in the water were shorter than 30mm because of the electrons energy having around 6MeV. These results clearly appears that the substraction of scattered electrons (electrons and positrons) from the total depth dose curve not only lowers the absolute dose in the bulidup region and surface dose, it also causes a shift of d$_{max}$ to a deeper depth. In the terapeutic high energy photon beam, the absorbed dose near the buildup region is the combined result of incident contaminant electrons and phantom generated electronsrons.

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Bioequivalence Study of Toriem® Tablet to Motilium-M® Tablet (Domperidone Maleate 12.72 mg) Evaluated by Liquid Chromatography/Tandem Mass Spectrometry

  • Ryu, Ju-Hee;Choi, Sang-Jun;Lee, Myung-Jae;Lee, Jin-Sung;Kang, Jong-Min;Tak, Sung-Kwon;Seo, Ji-Hyung;Lee, Kyung-Tae
    • Journal of Pharmaceutical Investigation
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    • v.39 no.1
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    • pp.65-71
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    • 2009
  • The aim of the present study was to evaluate the bioequivalence of two domperidone maleate tablets, Motilium-$M^{(R)}$ Tablet (Janssen Korea Ltd., reference product) and $Toriem^{(R)}$ Tablet (Daewon Pharm. Co., Ltd., test product). Domperidone was extracted by liquid-liquid extraction using tert-butyl methyl ether and separated in less than 3 min on $C_{18}$ reverse-phase column using an isocratic elution. A tandem mass spectrometer, as detector, was used for quantitative analysis in positive mode by a multiple reaction monitoring mode to monitor the m/z $426.1{\rightarrow}119.1$ and the m/z $837.4{\rightarrow}158.2$ transitions for domperidone and the internal standard (roxithromycin), respectively. Calibration curves, from $0.05{\sim}50$ ng/mL of domperidone, showed correlation coefficients (r) higher than 0.9941. Intra day and inter day precision (C.V. %) for quality control were ranged from 10.04 to 16.09% and from 10.87 to 18.69%, respectively. The lower limit of quantification (LLOQ) of domperidone was 0.05 ng/mL. The method described is precise and sensitive and has been successfully applied to the study of bioequivalence of domperidone in 24 healthy Korean volunteers. Twenty-four healthy male Korean volunteers received a single dose of each medicine ($2{\times}12.72\;mg$ domperidone maleate) in a $2{\times}2$ crossover study. There was a one-week washout period between the doses. Plasma concentrations of domperidone were monitored for over a period of 24 hr after the administration. $AUC_{0-t}$ (the area under the plasma concentration-time curve) was calculated by the linear trapezoidal rule. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. The 90% confidence intervals for the log transformed data were within acceptable range of log 0.8 to log 1.25 (e.g., $log\;0.92{\sim}log\;1.05$ for $AUC_{0-t}$, $log\;0.81{\sim}log\;1.05$ for $C_{max}$). The major parameters, $AUC_{0-t}$ and $C_{max}$ met the criteria of KFDA for bioequivalence indicating that $Toriem^{(R)}$ tablet is bioequivalent to Motilium-$M^{(R)}$ tablet.

Effect of Additive, Storage Temperature and Time on the Texture Properties of Baikseolgi (첨가물, 저장온도 및 저장시간에 따른 백설기의 텍스쳐 특성)

  • Kim, Myung-Hwan
    • Applied Biological Chemistry
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    • v.41 no.6
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    • pp.437-441
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    • 1998
  • The effects of sucrose fatty acid ester (SE, 1% w/w) and glycerin (GL, 1% v/w) additions, storage temperature$(0,\;20\;and\;70^{\circ}C)$, and time $(0{\sim}6\;day)$ on texture properties, hardness(H), cohesiveness(O), chewiness(C) and rheological property(R) of Baikseolgi were studied. The H of Baikseolgi increased sharply in the early stage of storage at 0 and $20^{\circ}C$, while increased gently at $70^{\circ}C$ with increasing storage time. After 6 days of storage, the H of Baikseolgi at $20^{\circ}C$ had a little lower than that at $0^{\circ}C$. However, the H of Baikseolgi at $70^{\circ}C$ was 10.7% of that at $0^{\circ}C$. The addition of GL had greater effect on the reduction of H than that of SE. The H of control, SE and GL additions were 336, 216 and $$174\;g_f, respectively, after 6 days at $70^{\circ}C$. The O of Baikseolgi at $70^{\circ}C$ were higher than those at $0^{\circ}C$. The O of GL added Baikseolgi had the highest value and the second and the third were SE added and control, respectively. The O of Baikseolgi decreased with increasing storage time. The C of Baikseolgi of increased with increasing storage time, which had similar curve patterns to the H of Baikseolgi. Instantaneous stress and equilibrium stress of Baikseolgi decreased with increasing storage temperature. The affection of viscous element increased and that of elastic element decreased with increasing storage temperature.

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PHOTOELECTRIC OBSERVATIONS AND UBVRI LIGHT CURVES ANALYSIS OF ALGOL (Algol의 광전측광관측과 UBVRI 광도곡선의 분석)

  • 정장해;이용삼;임조령;양감징
    • Journal of Astronomy and Space Sciences
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    • v.10 no.2
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    • pp.123-145
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    • 1993
  • UBVRi photometry of Algol was carried out from December of 1988 to March of 1991 at Chungbuk National University Observatory and a total of 3465 observations in U, B, V, R, I were obtained. Three times of primary minimum light of JDH el 2447898.0938, JEH el 2448265.1205 and JDH el 2448288.0598, and two secondary minimum light of JDH el 2447808.1014 and JDH el 2448275.146 were determined from our observations. We analyzed simultaneously the UBVRI light curves of the Algol system with the Wilson-Devinney method for the determination of the photometric parameters. Indivisual masses for the 3 components of Algol are derived as $m_1$=3.36, $m_2$=0.76, $m_3$=1.6 in solar mass and radii as $R_1$=2.97, $R_2$=0.76 in solar radinus using i=$82.{\circ}47$, q=0.227, $r_1$=0.2102, $r_2$=0.2512 of our solution and some parameters of the spectroscopic solution of Hill et al. (1971). Our results is simiar to those reported by Kim (1989). The temperature of Algol C, $T_3$=8800 was obtained by means of fitting $l_1$, $l_2$, and $l_3$ of five colors to Planckian curve, and $R_3$=$1.6R_\odot$ is derived from its result. It is believed that its semidetached configuration of Algol A and B is the consequence of case B mass transfer. According to its location in a mass-radius diagram. Algol b may have evolved significantly in its Hburnning phase.

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Analysis of Relative Breakage Hazard Rate of Water Mains Using the Proportional Hazards Model (비례위험모형을 이용한 상수관로의 상대적 파손위험율 분석)

  • Park, Su-Wan;Kim, Jung-Wook;Im, Gwang-Chae;Lee, Hyeong-Seok
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.490-494
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    • 2008
  • 본 연구에서는 상수도 배수관로의 내 외부적 특성에 따라 개별관로를 정의하는 방법을 연구대상 지역의 배수관로 파손 데이터베이스에 적용하여 비례위험모형을 구축하였다. 연구에 사용된 자료는 연구대상지역의 배수관로의 제원 및 파손시기를 포함하는 관로 파손데이터베이스, 관로매설지역의 급수인구 및 수압범위에 관한 자료를 포함하는 GRID 데이터베이스와 관로매설지역의 토지개발 정도에 관한 자료를 포함한다. 이러한 자료를 이용하여 관로를 순차적 파손경험에 따라 7개의 생존시간군(STG I $\sim$ VII)으로 구분하고 각 생존시간군에 대한 비례위험모형(Model I $\sim$ VII)을 구축하였다. 이러한 모형을 이용하여 관로의 파손횟수가 증가하는 동안 파손에 영향을 미치는 인자의 변화와 그 효과를 파악하였으며, 또한 추정된 공변수의 위험비율을 분석함으로써 관로의 제원 혹은 매설환경, 급수인구 등에 따른 위험률의 상대적인 변화를 분석하였다. 또한 비례 위험모형의 구축과정에서 관로의 파손에 영향을 미치는 공변수의 비례성 가정을 검토하여 시간종속형 공변수를 모형화하였으며, 모형의 이탈잔차(deviance residual)를 분석하여 모형의 적합성을 검토하였다. 본 연구에서 구축된 비례위험모형에 대해 Shoenfeld 잔차를 이용한 스코어 잔차의 변화(score process)를 검토한 결과, Model I 과 Model II 에 대해서는 공변수의 시간종속 효과가 발견되었다. Model I에 대해서는 관로재질과 급수인구의 영향이 시간에 따라 변하며 Model II에서는 급수인구의 영향만이 시간에 따라 변하는 것으로 나타났다. 한편 Model III $\sim$ Model VII 들에 대해서는 공변수의 영향이 시간에 따라 변하지 않는 것으로 나타났다. 각 생존시간군에 대해 관로재질, 토지개발정도, 관로길이 및 급수인구의 변화가 관로의 상대적 누수위험률에 미치는 영향을 상대위험률의 95% 신뢰구간을 고려하여 정량적으로 산정하였고, 시간 종속형 공변수로 모형화된 공변수는 시간에 따른 공변수 영향의 변화를 분석하였다. 순차적 파손사건에 대한 비례위험모형의 구축 결과 생존시간군(STG) I의 기저위험률은 매설 후 대략 450개월까지는 파손 위험률이 '0'에 가까우나 그 이후로 급격히 증가하다가 매설 후 약 700개월에 이르러서는 약간 감소하고 약 850개월 이후에는 다시 급격히 증가한다. STG II의 기저위험률은 첫 번째 파손 후 약 300개월이 되면 위험률이 급격히 증가하는 것으로 나타났다. STG III $\sim$ STG VII의 기저위험률은 이차함수의 형태를 띄며, 특히 STG V, STG VI 및 STG VII의 기저위험률은 욕조형 곡선(bathtub curve)의 형태를 가진다. 각 생존시간군의 기저생존함수의 생존확률 '0.5'에 해당하는 기저중간생존시간에 대한 분석으로부터 파손횟수가 많아질수록 순차적 파손사건 사이의 경과시간은 감소하는 것으로 나타났다. 이러한 기저생존시간에 대한 경향은 관로의 파손횟수가 많아질수록 관로의 일반적은 내구성은 감소하기 때문인 것으로 분석된다.

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Nitrogen Removal Characteristic of Excreta Wastewater Using SBR and MBR Processes (SBR 및 MBR 공정을 이용한 분뇨폐수에서의 질소제거 특성)

  • Jung, Jin-Hee;Yoon, Young-Nae;Lee, Seul-Kee;Han, Young-Rip;Lee, Seung-Chul;Choi, Young-Ik
    • Journal of Environmental Science International
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    • v.24 no.11
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    • pp.1485-1491
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    • 2015
  • There are two treatment processes that are currently applied to ships are the biological treatment process using the activated sludge and the electrochemical treatment. However, neither of them are able to remove both nitrogen and phosphorus due to their limited ability to remove organic matters, which are main causes of the red tide. This study was conducted to identify the characteristics of nitrogen removal factors from manure wastewater by replacing the final settling tank in SBR (Sequencing Batch Reactor) process and applying immersion type hollow fiber membrane. SBR process is known to have an advantage of the least land requirement in special environment such as in ship and the immersion type hollow fiber membrane is more stable in water quality change. As the result, the average in the cases of DO (Dissolved Oxygen) is 2.9(0. 6~3.9) mg/L which was determined to be the denitrifying microorganism activity in anaerobic conditions. The average in the cases of ORP (Oxidation Reduction Potential) is 98.4~237.3 mV which was determined to be the termination of nitrification since the inflection point was formed on the ORP curve due to decrease in the stirring treatment after the aeration, same as in the cases of DO. Little or no variation in the pH was determined to have positive effect on the nitrification. T-N (Total Nitrigen) removal efficiencies of the finally treated water were 71.4%, 72.3% and 66.5% in relatively average figures, thus was not a distinct prominence. In being applied in ships in the future, the operating conditions and structure improvements are deemed necessary since the MEPC (Marine Environment Protection Committee). 227(64) ship sewage nitrogen is less than the standard of 20 Qi/Qe mg/L or the removal rate of 70%.

Effects of Low Air Temperature and Low Radiation Conditions on Yield and Quality of Hot Pepper at the Early Growth Stage (생육 초기의 저온·저일조가 고추의 수량과 품질에 미치는 영향)

  • Wi, Seung Hwan;Lee, Hee Ju;Yu, In Ho;Jang, Yoon Ah;Yeo, Kyung Hwan;An, Se Woong;Lee, Jin Hyong;Kim, Sung Kyeom
    • Journal of Environmental Science International
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    • v.29 no.10
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    • pp.989-996
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    • 2020
  • This study was conducted to determine the effect of low temperature and low radiation conditions on the yield and quality of hot pepper at an early growth stage in Korea. In plastic greenhouses, low temperature, low temperature with covered shading treatments were set 17 to 42 days after transplanting. The pepper growing degree days decreased by 5.5% due to the low temperature during the treatment period. Radiation decreased by 74.7% due to the covered shading. After commencing treatments, pepper plant growth decreased with low temperature and low radiation. Analysis of the yield showed that the first harvest was delayed by low radiation. The cumulative yields of 119 days after transplanting were 1,956, 2,171, and 2,018 g/㎡ for control, low temperature, and low temperature with low radiation respectively. Capsaicin and dihydrocapsaicin concentrations in pepper fruit decreased with low temperature and low radiation. To investigate the photosynthetic characteristics according to the treatment, the carbon dioxide reaction curve was analyzed using the biochemical model of photosynthesis. Results showed that the maximum photosynthetic rate, Vcmax (maximum carboxylation rate), J (electric transportation rate), and TPU (triose phosphate utilization) decreased at low temperatures; the maximum photosynthetic rate, J, and gm (dark respiration rate) were reduced by shading. These results indicate that low temperature and low radiation can retard early growth, yield, and quality, but these can also be recovered 119 days after planting. Based on the results, the yield and quality of pepper can recover from abiotic stresses with proper cultivation.

Development of OSL Dosimetry Reader (선량 판독용 OSL 측정장치의 개발)

  • Park, Chang-Young;Chung, Ki-Soo;Lee, Jong-Duk;Chang, In-Su;Lee, Jung-Il;Kim, Jang-Lyul
    • Journal of Radiation Protection and Research
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    • v.37 no.1
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    • pp.10-15
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    • 2012
  • Design and performance test results of a newly developed optically stimulated luminescence (OSL) measurement system are presented in this paper. Generally, different types of optical filters are used in OSL reader system to minimize the interference of the stimulation light in the OSL signal. For optically stimulation of $Al_2O_3:C$, we have arrived at an optimal combination of the filters, i.e., GG420 filter for filtering the stimulating light source, and a combined UG11 and BG39 filter at the detecting window (PMT). By using a high luminance blue LED (Luxeon V), sufficient luminous intensity could be obtained for optically stimulation. By using various control boards, the OSL reader device was successfully interfaced with a personal computer. A software was developed to deliver required commands to operate the OSL reader by using the LabView program (National Instruments, Inc.). In order to evaluate the reliability and the reproducibility of newly designed-OSL reader. Performance testing of the OSL reader was carried out for OSL efficiency, OSL decay curve and signal to noise ratio of the standard $Al_2O_3:C$ OSL material. It was found to be comparable with that of commercial Riso reader system.