• Applied Biological Chemistry
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• v.48 no.4
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• pp.421-424
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• 2005

The leaf of Petasites japonicus was extracted with 80% aqueous MeOH and solvent fractionated with EtOAc, n-BuOH and water successively. From the EtOAc fractions, two triterpenoids were isolated through the repeated silica gel and ODS column chromatographies. The chemical structures of the isolated terpenoids were determined as rosamutin (1) and peduncloside (2) through the interpretation of several spectral data including 2D-NMR such as $^1H-{^1H}$ gCOSY, gHSQC and gHMBC.

• Journal of The Korean Astronomical Society
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• v.39 no.1
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• pp.19-24
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• 2006

We carried out CO survey toward IR-excess clouds using SRAO 6-m telescope in search of molecular $H_2$. These clouds, which show far-infrared excess over what is expected from HI column density, are considered to be candidates of molecular clouds. In order to find new high Galactic latitude clouds, we made mapping observations for 14 IR-excess clouds selected from Reach et al.(1998) in $^{12}CO$ J = 1 - 0 line, supplementing the similar survey in southern hemisphere (Onishi et al. 2001). $^{12}CO$ emission is detected from three IR-excess clouds among 14 objects. Three newly detected clouds exhibit somewhat clumpy morphology and column densities amount to ${\sim}10^{21}\;cm^{-2}$. One of three clouds, DIR120-28, show discrepancy between IR-excess center and CO emission center. It seems that IR-excess may not be an effective tracer of molecular gas. Instead, optical depth$(\tau)$ excess, i.e., IR-excess corrected for temperature dependence, may be more effective tracer of molecular clouds, since, by combining statistics from both hemispheres, we found that the detection rate is higher for IR-excess clouds with lower dust temperature.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.4
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• pp.238-243
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• 2001

대기중의 $CO_2$ 농도 상승은 지구온난화의 주원인이 되고 있는데, 1960년대 전반에 320$\mu$㏖ㆍ㏖$^{-1}$ 이하 였던 $CO_2$농도가 화석연료의 사용량 증가, 삼림 벌채 등의 영향으로 근년에는 360 $\mu$㏖ㆍ㏖$^{-1}$ 이상으로 상승하였다(Bagastow et al., 1985). 이러한 추세로 대기중의 $CO_2$ 농도가 증가한다면 21세기 말에는 $CO_2$ 농도가 현재의 약 2배로 상승되고, 2~6$^{\circ}C$의 기온 상승이 예측되어 (Burroughs, 2001) 지구차원의 환경문제로 대두되고 있다.(중략)

• Journal of Pharmaceutical Investigation
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• v.36 no.2
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• pp.137-142
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• 2006

A bioequivalence of Daewoong $Alendronate^{TM}$ (Daewoong Pharmaceutical Co., Ltd., Korea) and $Fosamax^{TM}$ tablets (MSD Korea) was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). A single 70 mg dose of sodium alendronate of each medicine was administered orally to 56 healthy male volunteers. This study was performed in a $2\;{\time}\;2$ crossover design. Concentrations of alendronate in the urine were monitored by a high-performance liquid chromatography (HPLC). $A_{et}$ (cumulative urinary excreted amount from time 0 to last sampling interval) was calculated by the accumulation of the urinary excreted alendronate. $U_{max}$ (maximum urinary excretion rate) and $T_{max}$ (time to reach $U_{max}$) were compiled from the urinary excretion rate - time data. Analysis of variance was performed using logarithmically transformed $A_{et}$ and $U_{max}$. No significant sequence effect was found for all of the bioavailability parameters. The 90% confidence intervals of the $A_{et}$ and $U_{max}$ for Daewoong $Alendronate^{TM}/Fosamax^{TM}$ were 0.89-1.12 and 0.82-1.02, respectively. This study demonstrated the bioequivalence of Daewoong $Alendronate^{TM}$ and $Fosamax^{TM}$ with respect to the rate and extent of absorption.

• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.246-251
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• 2009

This study examined the possible hypoglycemic effects Angelica gigas Naki extracts in streptozotocin-induced diabetic rats(STZ+50%, STZ+100% EtOH and STZ+water). The studies showed that administration of the Angelica gigas Naki extract decreased high blood glucose levels(more than 300 mg/$d{\ell}$) to a normal level(104 mg/$d{\ell}$) in the STZ+50% EtOH group. Liver glucokinase levels were significantly increased in STZ+50% EtOH and STZ+100% EtOH groups compared to the STZ group. Moreover, the liver acetyl CoA carboxylase level was significantly increased in STZ+50% EtOH, STZ+100% EtOH and STZ+water groups compared to the STZ group. These results suggest that the Angelica gigas Naki extract in the STZ+50% EtOH group exerted an ameliorable effect and can be used as an anti-diabetic substance, either as a dietary supplements or as a new drug.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.3
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• pp.263-271
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• 2007

The heat transfer coefficient and pressure drop during 9as cooling process of $CO_2$ (R744) in a helically coiled copper tube with the inner diameter of 4.55 mm and outer diameter of 6.35 mm were investigated experimentally. The main components of the refrigerant loop are a receiver, a variable-speed pump. a mass flow meter a pre-heater and a helically coiled type gas cooler (test section). The refrigerant mass fluxes are varied from 200 to $800kg/m^2s$ and the inlet pressures of gas cooler are 7.5 to 10.0 MPa. The heat transfer coefficients of $CO_2$ in a helically coiled tube are higher than those in a horizontal tube. The Pressure drop of $CO_2$ in the gas cooler shows a relatively good agreement with those predicted by Ito's correlation developed for single-phase in a helically coiled tube. The local heat transfer coefficient of $CO_2$ agrees well with the correlation by Pitla et al. However. at the region near pseudo-critical temperature. the experiments indicate higher values than the Pitla et al correlation. Therefore, various experiments in helically coiled tubes have to be conducted and it is necessary to develop the reliable and accurate prediction determining the heat transfer and pressure drop of $CO_2$ in a helically coiled tube.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.3
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• pp.61-68
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• 2011

유럽연합(EU)은 2012년부터 항공산업에 대해 탄소배출권 거래제도를 적용할 예정이다. 따라서 유럽공항에서 출발 및 도착하는 모든 국제선과 국내선 항공편에 대해 탄소세가 부과될 것이며 이는 한국도 예외는 아니다. 또한 유럽을 운항하는 경우 장거리에 해당되어 중단거리를 운항하는 항공기들에 비해 총 탄소배출량이 더 많으므로 비용부담이 커질 것으로 예상된다. 본 연구는 EU-ETS로 인한 탄소세가 항공요금에 반영된다면 항공여객들이 어느 정도 민감하게 반응할 것이며 이러한 점들이 궁극적으로 한국의 항공시장에 어떤 영향을 미칠 것인지를 파악해 보는데 목적이 있다. 이를 위해 인천국제공항에서 프랑크푸르트 국제공항 노선을 이용하는 승객을 대상으로 직항노선과 중동지역 경유노선을 비교하여 EU-ETS 가격이 반영된 항공요금에 대한 반응을 Revealed Preference (RP)와 Stated Preference (SP) 설문자료와 Logit Model을 사용하여 분석하였다. 본 연구결과는 한국의 항공산업은 물론 2012년부터 부과될 EU-ETS에 대한 항공사들의 전략개발에 도움이 될 것이다.

• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2383-2389
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• 2008

• Journal of the Korean Society of Combustion
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• v.16 no.4
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• pp.38-45
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• 2011

Coal-derived syngas has been utilized by main fuel at IGCC power plant. Research efforts for investigating the characteristics of premixed and nonpremixed flames at gas-turbine condition have been conducted. The present study has been mainly motivated to evaluate the capability of the detailed chemical kinetics to predict the syngas laminar flame speed. Special emphasis is given to the effects of pressure, temperature, syngas composition, and dilution level on the characteristics of premixed and nonpremixed flames. The predicative capability of a number of detailed mechanism for laminar flame speed is compared to experimental data. From these results, detailed kinetics of Davis et al. and Li et al. have the best conformity with the experiments in the all the case of parametric studies.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.923-926
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• 2016

The classic BCR-ABL1-negative myeloproliferative neoplasm is an operational sub-category of MPNs that includes polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). The JAK2V617F mutation is found in ~ 95% of PV and 50-60% of ET or PMF. In most of the remaining JAK2V617F-negative PV cases, JAK2 exon 12 mutations are present. Amongst the JAK2V617F-negative ET or PMF 5-10% of patients carry mutations in the MPL gene. Prior to 2013, there was no specific molecular marker described in the remaining 30-40% ET and PMF. In December 2013, two research groups independently reported mutations in the gene CALR found specifically in ET (67-71%) and PMF (56-88%) but not in PV. Initially CALR mutations were reported mutually exclusive with JAK2 or MPL. However, co-occurrence of CALR mutations with JAK2V617F has been reported recently in a few MPN cases. Many studies have reported important diagnostic and prognostic significance of CALR mutations in ET and PMF patients and CALR mutation screening has been proposed to be incorporated into WHO diagnostic criteria for MPN. It is suggestive in diagnostic workup of MPN that CALR mutations should not be studied in MPN patients who carry JAK2 or MPL mutations. However JAK2V617F and CALR positive patients might have a different phenotype and clinical course, distinct from the JAK2-positive or CALR-positive subgroups and identification of the true frequency of these patients may be an important factor for defining the prognosis, risk factors and outcomes for MPN patients.