• The Korean Journal of Physiology and Pharmacology
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• 제8권1호
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• pp.65-67
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• 2004

Dehydroevodiamine (DHED) is one of the bioactive components of the Chinese herbal medicine Wu-chu-yu-tang that has been shown to produce various pharmacological effects. In the present study, we investigated the pharmacokinetics of DHED after intravenous administration of two doses (2.5 and 5 mg/kg) in anesthetized rats. The plasma concentration of DHED was measured by reverse-phase high-performance liquid chromatography with UV detection. The mean area under the curve of the time-concentration profile was $21.9\;and\;53.9\;{\mu}g{\cdot}min/ml$ after the 2.5- and 5-mg/kg doses, respectively, and the volume of distribution was 1584.9 and 1580.6 ml following 2.5- and 5-mg/kg doses, respectively. Plasma concentration profiles versus time were compatible with a two-compartment model and first-order kinetics. The terminal elimination half-life was $91.8{\pm}16.6\;min$ and $78.7{\pm}11.9\;min$ in the dose of 2.5 and 5 mg/kg, respectively. This is the first report to study the pharmacokinetics of DHED in animals.

• 한국동물위생학회지
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• 제25권3호
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• pp.299-308
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• 2002

The purposes of this study were to characterize the disposition of sulfathiazole(ST) and to investigate the effects of sodium bicarbonate on the disposition of ST in broiler chicks(2.5～3.0kg). Animals were given ST acutely(10～80mg/kg, PO), and plasma, kidney, muscle, heart, liver and spleen samples were collected and analyzed for ST by high performance liquid chromatography. The plasma and tissue data was consistent with a one-compartment pharmacokinetic model. The drug is rapidly but incompletely(2.5～3.87%) absorbed with peak plasma and tissue levels being achieved within one hour after dosing. The plasma and tissue levels depended on drug dosage, and the descending order in concentration of ST was kidney > plasma > heart > muscle $\geq$ spleen $\geq$ liver from animals sacrificed at one hour after dosing. Moreover, significant positive correlations(r>0.9) existed between plasma and tissue levels of ST. In addition, sodium bicarbonate pretreatment decreased plasma level, indicating that an alkalinization stimulate the excretion of ST. Results of this study suggest that oral application of ST was rapidly absorbed and eliminated, and confirmed that tissue residues of ST can be estimated from plasma drug concentration in broiler chicks.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2010년도 추계학술발표회 자료집
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• pp.241-245
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• 2010

화재방호에 성능기반 개념을 도입함에 따라 화재모델링의 활용도는 점점 높아지고 있다. 본 연구의 목적은 FDS를 이용하여 원자력발전소 펌프실의 윤활유 화재 시 케이블의 손상여부를 평가하고, 확인분석을 통해 화재모델링의 적합성을 파악하는 데 있다. 화재는 펌프 주변의 누출된 윤활유에서 발생하며 화원의 면적은 $2.75m^2$이고 단위면적당 열방출율은 $1,794kW/m^2$로 가정하였다. 계산결과, 고온기체층의 온도는 $400^{\circ}C$를 상회하고 있으나 케이블 트레이의 온도는 $50^{\circ}C$ 아래로 예측되고 있어 본 화재시나리오에서 케이블의 건전성은 유지되고 있으며 밀폐된 격실에서의 대형화재는 환기지배형 화재가 된다는 것을 보여주고 있다. 또한 확인분석 결과, 화재 시나리오의 주요 변수인 열방출율, 격실크기 그리고 강제 환기 변수가 확인계산 범위 내에 있어 본 계산결과는 NUREG-1824의 확인요건을 만족하고 있다. 따라서 펌프실 윤활유 화재에 대한 모델링의 적합성을 확인하였다.

• Nuclear Engineering and Technology
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• 제35권2호
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• pp.108-120
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• 2003

In assessing the long term post closure radiological safety assessment of a potential HLW repository in Korea, three categories of uncertainties exist. The first one is the scenario uncertainty where series of different natural events are translated into written statements. The second one is the modeling uncertatinty where different mathematical models are applied for an identical scenario. The last one is the data uncertainty which can be expressed in terms of probabilistic density functions. In this analysis, three different scenarios are seleceted; a small well scenario, a radiolysis scenario, and a naturally discharged scenario. The MASCOT-K and the AMBER, probabilistic safety assessment codes based on connection of sub-modules and a compartment theory respectively, are applied to assess annual individual doses for a generic biosphere. Results illustrate that for a given scenario, predictions from two different codes fairly match well each other But the discrepancies for the different scenarios are significant. However, total doses are still well below the guideline of 2 mRem/yr. Detailed analyses with model and data uncertainties are underway to further assure the safety of a Korean reference dispsoal concept.

• Archives of Pharmacal Research
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• 제29권7호
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• pp.598-604
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• 2006

In many conventional drug delivery systems in vogue, failure to deliver efficient drug delivery at the target site/organs; is evident as a result, less efficacious pharmacological response is elicited. Microspheres can be derived a remedial measure which can improve site-specific drug delivery to a considerable extent. As an application, Lung-targeting Ofloxacin-loaded gelatin microspheres (GLOME) were prepared by water in oil emulsion method. The Central Composite Design (CCD) was used to optimize the process of preparation, the appearance and size distribution were examined by scanning electron microscopy, the aspects such as in vitro release characteristics, stability, drug loading, loading efficiency, pharmacokinetics and tissue distribution in albino mice were studied. The experimental results showed that the microspheres in the range of $0.32-22\;{\mu}m$. The drug loading and loading efficiency were 61.05 and 91.55% respectively. The in vitro release profile of the microspheres matched the korsmeyer’s peppas release pattern, and release at 1h was 42%, while for the original drug, ofloxacin under the same conditions 90.02% released in the first half an hour. After i.v. administration (15 min), the drug concentration of microspheres group in lung in albino mice was $1048\;{\mu}g/g$, while that of controlled group was $6.77\;{\mu}g/g$. GLOME found to release the drug to a maximum extent in the target tissue, lungs.

• 대한약리학회지
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• 제25권1호
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• pp.101-107
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• 1989

Procainamide를 투여후 이 약물 및 활성형 대사산물인 N-acetylprocainamide (NAPA)의 약동학적 성상을 알아보기 위해 숫컷 성견 5마리에 procainamide 및 NAPA를 교차 투여하여 얻은 혈장농도 data를 2-compartmental model에 의해 약동학적 분석을 시행하여 다음과 같은 결과를 얻었다. 1. 10mg/kg의 procainamide를 1회 15분간 정주후 혈장 procainamide 농도변화는 명백한 분포기와 소실기를 보였으며 생성된 NAPA의 혈장농도는 시간경과에 따라 최고혈장농도는 $0.124{\mu}g/ml$ 이하이었으며 정주 직후 조직분포에 따른 혈장농도의 일시적으로 감소 후 증가하는 초기 dip 현상을 보였다. 2. Procainamide의 steady-state 분포용적(Vss) 및 central compartment volume (Vc)은 각각 $1.20{\pm}0.27\;L/kg$ 및 $0.36{\pm}0.08\;L/kg$ 이였으며 NAPA의 Vss및 Vd는 $1.21{\pm}0.21\;L/kg$ 및 $0.26{\pm}0.07\;L/kg$이었다. 3. Procainamide 및 NAPA의 청소율(Cl)은 각 $0.47{\pm}0.08\;L/kg/hr$와 $0.35{\pm}0.08\;L/kg/hr$ 이었으며 혈장 반감기$(t_{1/2{\beta}})$는 각각 2.85 및 2.77 시간이었다. 4. N-acetylation에 의한 Procainamide의 대사청소율은 $18.24{\pm}6.22\;ml/kg/hr$로 이는 전체 procainamide 청소율의 3.9%를 차지하였다.

• Journal of Radiation Protection and Research
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• 제33권4호
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• pp.135-141
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• 2008

본 논문은 벼에 $^{14}CO_2$ 가스를 단기간 동안 직접 노출시켜 시간대 별 $^{14}C$의 전이 현상에 대한 동적 예측 모델과 동 모델의 타당성을 조사하기 위해 수행된 벼의 $^{14}CO_2$ 피폭 실험에 대해 기술하였다. 본 모델에서 작물은 몸체와 이삭(쌀알)의 두 격실로 구분되었고, 식물의 광합성과 연관된 매개변수의 함수로 표현되는 5개의 격실 간 탄소이동을 고려하였다. 모델예측을 통해 작물의 $^{14}C$ 방사능 오염에 대한 $^{14}CO_2$, 누출 시기 및 지속시간, 매개변수의 영향을 분석하였다. $^{14}CO_2$ 누출 지속시간이 길어지면 본 모델은 비 방사능 모델 적용 영역으로 수렴되었다. 작물의 $^{14}C$ 오염은 광합성이 가장 왕성한 개화기부터 수확기 사이에 작물이 $^{14}CO_2$에 노출되었을 때 가장 큰 것으로 예측되었다. $^{14}CO_2$에 대한 벼 노출 실험결과와 모델예측결과의 비교로부터 본 모델은 벼의 $^{14}C$ 흡수 예측 모델로 충분히 활용할 수 있음을 확인하였다.

• 한국환경과학회지
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• 제24권10호
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• pp.1273-1283
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• 2015

In present study, the temporal characteristics of nine selected volatile organic compounds (VOCs), including four alcohol, 2 aldehyde, and 3 ketone compounds, in high-stories urban apartments over a 2-y period were investigated. The indoor VOC concentrations had generally a decreasing trend over the 2-y follow-up period. For examples, the 2E1H indoor concentration decreased from $10.8{\mu}g/m^3$ for the first two months to $5.1{\mu}g/m^3$ for the last two months. In addition, the DCA and ACT indoor concentrations decreased from 5.0 and $14{\mu}g/m^3$ for the first two months to 2.2 and $6.4{\mu}g/m^3$, respectively, for the last two months. The indoor-to outdoor concentration ratios over the 2-y period were much greater than 1, indicating that indoor VOC concentrations were higher than the outdoor VOC concentrations. Similar to those of the individual VOCs, the indoor-to-outdoor concentration ratios of all three VOC groups were higher than 1 over the 2-y follow-up period, suggesting higher indoor concentrations of the three VOC groups than outdoor concentrations. In consistence with the results of VOC indoor concentrations, the VOC emission rates decreased gradually as time passed, due to the decreased VOC emission strengths of indoor sources. Finally, there was an initial sharp decrease in the indoor VOC concentrations followed by a slower decrease, indicating a multi-exponential decay model for the target VOCs, which was demonstrated by comparison of the residuals and the adjusted coefficient of determination associated with the one and two-exponential fits of each data set.

• 한국자동차공학회논문집
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• 제18권5호
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• pp.115-123
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• 2010

Cool-down performance after soaking is important because it affects passenger's thermal comfort. The cooling capacity of HVAC system determines initial cool down performance in most cases, the performance is also affected by location, and shape of panel vent, indoor seat arrangement. Therefore, optimal indoor designs are required in developing a new car. In this paper, initial cool down performance is predicted by CFD(computational fluid dynamics) analysis. Experimental time-averaging temperature data are used as inlet boundary condition. For more reliable analysis, real vehicle model and human FE model are used in grid generation procedure. Thermal and aerodynamic characteristics on re-circulation cool vent mode are investigated using CFX 12.0. Thermal comfort represented by PMV(predicted mean vote) is evaluated using acquired numerical data. Temperature and velocity fields show that flow in passenger's compartment after soaking is considerably unstable at the view point of thermodynamics. Volume-averaged temperature is decreased exponentially during overall cool down process. However, temperature monitored at different 16 spots in CFX-Solver shows local variation in head, chest, knee, foot. The cooling speed at the head and chest nearby panel vent are relatively faster than at the knee and foot. Horizontal temperature contour shows asymmetric distribution because of the location of exhaust vent. By evaluating the passenger's thermal comfort, slowest cooling region is found at the driver's seat.

• Environmental Analysis Health and Toxicology
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• 제28권
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• pp.13.1-13.5
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• 2013

Objectives: Potential environmental risks caused by chemicals that could be released from a recycled plastic product were assessed using a screening risk assessment procedure for chemicals in recycled products. Methods: Plastic slope protection blocks manufactured from recycled plastics were chosen as model recycled products. Ecological risks caused by four model chemicals - di-(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), cadmium (Cd), and lead (Pb)-were assessed. Two exposure models were built for soil below the block and a hypothetic stream receiving runoff water. Based on the predicted no-effect concentrations for the selected chemicals and exposure scenarios, the allowable leaching rates from and the allowable contents in the recycled plastic blocks were also derived. Results: Environmental risks posed by slope protection blocks were much higher in the soil compartment than in the hypothetic stream. The allowable concentrations in leachate were $1.0{\times}10^{-4}$, $1.2{\times}10^{-5}$, $9.5{\times}10^{-3}$, and $5.3{\times}10^{-3}mg/L$ for DEHP, DINP, Cd, and Pb, respectively. The allowable contents in the recycled products were $5.2{\times}10^{-3}$, $6.0{\times}10^{-4}$, $5.0{\times}10^{-1}$, and $2.7{\times}10^{-1}mg/kg$ for DEHP, DINP, Cd, and Pb, respectively. Conclusions: A systematic ecological risk assessment approach for slope protection blocks would be useful for regulatory decisions for setting the allowable emission rates of chemical contaminants, although the method needs refinement.