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A New Formulation of Controlled Release Amitriptyline Pellets and Its In Vivo/In Vitro Assessments

  • Park, Eun-Seok;Lee, Dong-Soo;Kwon, Seok-Young;Chi, Sang-Cheol
    • Archives of Pharmacal Research
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    • v.26 no.7
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    • pp.569-574
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    • 2003
  • Controlled-release amitriptyline pellets (ATP) were formulated and its oral bioavailability was assessed in human volunteers after oral administration under fasting conditions. Core pellets were prepared using a CF granulator by two different methods (powder layering and solvent spraying) and coated with Eudragit RS or RL 100. Physical characteristics and dissolution rates of core pellets and coated pellets were evaluated to optimize the formulation. Powder layering method resulted in a better surface morphology than solvent spraying method. However, physical properties of the products were poorer when prepared by powder layering method with respect to hardness, friability and density. The dissolution profile of amitriptyline coated with Eudragit RS 100 was comparable to that of commercially available amitriptyline enteric-coated pellets ($Saroten^{\circledR}$ retard). After the oral administration of both products at the dose of 50 mg, the mean maximum concentrations ($C_{max}$) were 36.4 and 29.7 ng/mL, and the mean areas under the concentration-time curve ($AUC_{0-96}$) were 1180.2 and 1010.7 ng.h/mL for ATP and Saroten retard, respectively. The time to reach the maximum concentrations ($T_{max}$) was 6 h for both formulations. Statistical evaluation suggested that ATP was bioequivalent to Saroten retard.

Selection Method for Optimal Shop Floor Control According to Manufacturing Environment (생산환경 변화에 따른 최적 Material Flow Control 선택방법)

  • Park, Sang Geun;Park, Sung Ho;Ha, Chunghun
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.36 no.2
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    • pp.81-90
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    • 2013
  • Material flow control (MFC) is a kind of operational policy to control of the movement of raw materials, components, and products through the manufacturing lines. It is very important because it varies throughput, line cycle time, and work-in-process (WIP) under the same manufacturing environments. MFC can be largely categorized into three types such as Push, Pull, and Hybrid. In this paper, we set various manufacturing environments to compare five existing MFC mechanisms: Push, Pull, and Hybrid (CONWIP, Gated MaxWIP, Critical WIP Loops, etc). Three manufacturing environments, manufacturing policies (make to stock and make to order), demand (low, medium, high), and line balancing (balanced, unbalanced, and highly unbalanced) are considered. The MFCs are compared in the point of the five functional efficiencies and the proposed compounded efficiency. The simulation results shows that the Push is superior in the functional efficiency and GMWIP is superior in the compounded efficiency.

2,4-D Biodegradation Using Microorganism Extracted From Soil (1) (토양미생물에 의한 2, 4-D 분해에 관한 연구 (1))

  • Choung, Youn-kyoo;Lee, Byung chan;Kim, Jin-wook
    • Journal of Korean Society of Water and Wastewater
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    • v.13 no.4
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    • pp.45-53
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    • 1999
  • The microbial organisms named "Pseudomonas sp. LK-14" were isolated from farm land and shallow river sediment, activated, augmented and identified; which were using 2,4-D (2,4-Dichlorophenoxyacetic acid) as a sole carbon source and energy source. 2,4-D removal efficiency of LK-14 with 2,4-D sole carbon source (reactor S) were higher than that of Activated Sludge with 2,4-D sole carbon source (reactor A). Dynamic bioligical reaction kinetic parameters (sole carbon source was 2,4-D) obtained from batch reactor experiments were ${\mu}_{max}$ $0.105hr^{-1}$, $K_{s,24D}$ 15.64mg/L, $K_{i,24D}$ $1.94h^{r-1}$, $Y_{24D}$ 0.39 for LK-14 and ${\mu}_{max}$ $0.008hr^{-1}$, $K_{s,24D}$ 26.95mg/L, $K_{i,24D}$ $1.75hr^{-1}$, $Y_{24D}$ 0.10 for Activated Sludge. Using these parameters, we could predict the behaviors of 2,4-D substrate utilized by LK-14 and Activated Sludge in batch reactors. The kinetic parameters are enable to predict the 2,4-D substrate and microbial population behavior entering into wastewater treatment plants by using unsteady states dynamic simulation modeling technique.

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Prediction of Viscosity in Liquid Epoxy Resin Mixed with Micro/Nano Hybrid Silica (액상 에폭시 수지와 마이크로/나노 하이브리드 실리카 혼합물의 점도 예측)

  • Huang, Guang-Chun;Lee, Chung-Hee;Lee, Jong-Keun
    • Korean Journal of Materials Research
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    • v.21 no.2
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    • pp.100-105
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    • 2011
  • The relative viscosity was measured at different filler loadings for a cycloaliphatic epoxy resin and hexahydro-4-methylphthalic anhydride hardener system filled with micro/nano hybrid silica. Various empirical models were fitted to the experimental data and a fitting parameter such as critical filler fractions (${\phi}_{max}$) was estimated. Among the models, the Zhang-Evans model gave the best fit to the viscosity data. For all the silica loadings used, ln (relative viscosity) varied linearly with filler loadings. Using the Zhang-Evans model and the linearity characteristics of the viscosity change, simple methods to predict the relative viscosity below ${\phi}_{max}$ are presented in this work. The predicted viscosity values from the two methods at hybrid silica fractions of $\phi$ = 0.086 and 0.1506 were confirmed for a micro:nano = 1:1 hybrid filler. As a result, the difference between measured and predicted values was less than 11%, indicating that the proposed predicting methods are in good agreement with the experiment.

Determination of Protein and Oil Contents in Soybean Seed by Near Infrared Reflectance Spectroscopy

  • Choung, Myoung-Gun;Baek, In-Youl;Kang, Sung-Taeg;Han, Won-Young;Shin, Doo-Chull;Moon, Huhn-Pal;Kang, Kwang-Hee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.46 no.2
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    • pp.106-111
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    • 2001
  • The applicability of near infrared reflectance spectroscopy(NIRS) was tested to determine the protein and oil contents in ground soybean [Glycine max (L.) Merr.] seeds. A total of 189 soybean calibration samples and 103 validation samples were used for NIRS equation development and validation, respectively. In the NIRS equation of protein, the most accurate equation was obtained at 2, 8, 6, 1(2nd derivative, 8 nm gap, 6 points smoothing and 1 point second smoothing) math treatment condition with SNV-D (Standard Normal Variate and Detrend) scatter correction method and entire spectrum by using MPLS (Modified Partial Least Squares) regression. In the case of oil, the best equation was obtained at 1, 4, 4, 1 condition with SNV-D scatter correction method and near infrared (1100-2500nm) region by using MPLS regression. Validation of these NIRS equations showed very low bias (protein:-0.016%, oil : -0.011 %) and standard error of prediction (SEP, protein: 0.437%, oil: 0.377%) and very high coefficient of determination ($R^2$, protein: 0.985, oil : 0.965). Therefore, these NIRS equation seems reliable for determining the protein and oil content, and NIRS method could be used as a mass screening method of soybean seed.

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Examination of Method of an Aircraft Noise Reduction -Mainly the Window Installation Conditions- (항공기소음 저감방안에 대한 검토 -창호설치조건을 중심으로-)

  • Yang, Jae-Hoon;Kim, Kyoung-Woo;Yang, Kwan-Seop
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.04a
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    • pp.260-263
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    • 2008
  • 공항에 인접한 주거지역에서 항공기 소음문제로 인하여 거주자들에게 소음피해가 발생하고 있다. 이러한 항공기소음을 저감하기 위한 방법 중 건물외피를 차음성능이 높은 구조로 변경하여 건축물의 차음량을 개선시키는 수음원 대책이 일반적으로 사용되고 있다. 특히 건축물 방음시설 설치는 건물외피 중 외부소음에 가장 취약한 창호의 차음량을 증가시키는 것이 효과적인데, 본 연구에서는 기존 창호에 비하여 차음성능이 높은 창호를 교체 설치하여 건축물의 차음량 개선치를 $L_{max}$, SEL, $L_{eq}$로 각각 검토 비교함과 동시에 창호의 기밀성능을 위한 기밀재 및 추가 모헤어의 설치조건에 따른 차음성능을 검토해 보았다. 측정결과 방음시설 설치 후 항공기소음을 $L_{max}$, SEL, $L_{eq}$로 차음량 개선치를 각각 평가한 결과 1.8dB 이내의 편차를 갖는 것으로 나타났으며, 창의 차음성능 개선치는 기밀재 설치 후 $R'45^{\circ}$,w가 5dB, 기밀재 및 추가 모헤어 설치 후 8dB로 나타났다.

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Relationship Between Organizational Communication Satisfaction and Organizational Commitment among Hospital Nurses (병원간호사의 의사소통 만족 수준이 조직몰입에 미치는 영향)

  • Kang, Kyeong-Hwa;Han, Yong-Hee;Kang, Soo-Jin
    • Journal of Korean Academy of Nursing Administration
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    • v.18 no.1
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    • pp.13-22
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    • 2012
  • Purpose: This study was done to analyze the relationship between organizational communication satisfaction and organizational commitment among hospital nurses. Method: A survey was conducted with 647 nurses who were working in 24 hospitals in Korea. Data were collected during August 2010. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation analysis, and multiple regression. Results: The mean level of organizational communication satisfaction was 3.15 (min 1.88 -max 4.88) and the mean level of organizational commitment was 3.21 (min 1.33 - max 4.83). There was a statistically significant correlation between organizational communication satisfaction and organizational commitment (r=. 655). According to analysis of the impact of the subconstructions of organizational communication satisfaction on organizational commitment, the following factors had significant influence on organizational communication satisfaction: vertical communication, communication media, and organizational climate. Conclusion: These findings showed that communication satisfaction was the most important factor for nurses' organizational commitment. Therefore, there is a need to develop communication strategies and skills for hospital nurses to increase the level of communication satisfaction.

The study on source regions of solar energetic particles detected by widely separated multiple spacecraft

  • Park, Jinhye;Innes, D.E.;Bucik, R.;Moon, Y.J.
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.110.1-110.1
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    • 2012
  • We studied the source regions of 12 solar energetic particle (SEP) events seen between 2010 August and 2012 January at STEREO-A, B and ACE, when the two STEREO spacecraft were separated by about $180^{\circ}$. All events were associated with strong flares (C1 - X6) and fast coronal mass ejections (CMEs) accompanied by type II radio bursts. We have determined the arrival times of the SEP events at the three spacecraft. EUV waves observed in $195{\AA}$ and $193{\AA}$ channels of STEREO and SDO/AIA are tracked across the Sun and the arrival time of the EUV wave at the photospheric source of open field lines extending to the spacecraft connection points at 2.5 Rsun estimated. We found 7 events with flux enhancements in all spacecraft and 4 in two spacecraft. Most events came from a single source. The results show that magnetic field connections between source regions and the spacecraft play an important role in abrupt flux enhancements. In the most cases, EUV waves at the Sun are associated with a wide longitudinal spread of the SEPs.

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The Study on the Bioavailability of the Phenytoin Products (페니토인 제제의 생체이용률에 관한 연구)

  • 박경호;김낙두;이민화
    • YAKHAK HOEJI
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    • v.30 no.1
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    • pp.14-23
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    • 1986
  • This study was conducted to investigate the correlation between the dissolution rates and the bioavailabilities of commercial phenytoin products, and also the correlation between their biovailabilities in rabbits and those in humans. Dissolution test was conducted in pH 9. 0 alkaline borate buffer (0.2M) using basket method with seven phenytoin products commercially available. According to the dissolution rate, the phenytoin products were divided into three groups, such as rapid, intermediate and slow group. Three phenytoin products from each group were selected for the bioavailability test in rabbits and humans. The bioavailability test was carried out in rabbits and normal volunteers using cross over design. Single doses of 20mg/kg and 300mg/man were orally administered to rabbits and normal volunteers respectively. Average $C_{max}$, $t_{max}$ and AUC of three phenytoin products were determined from the serum concentration-time curve in rabbit and human experiments. The relative bioavailability evaluation was conducted using AUC of three phenytoin products. The correlations between the dissolution rate constants and bioavailabilities (AUC) of three phenytoin products in rabbits as well as those in humans were not found. Whereas, there was significant correlation between average AUC of three phenytoin products in humans and those in rabbits (r=0.993, p<0.1). From the results of this experiment, it can be concluded that the bioavailability of phenytoin products in humans may be predicted from the results of the rabbit experiment. Also it is assumed that the prediction of the bioavailability of phenytoin products in humans may be difficult from the only results of in vitro dissolution test.

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Bioequivalence Study of Enalapril Tablet to $Lenipril^{(R)}$ Tablet (레니프릴정(에날라프릴 10 mg)에 대한 에날라프릴정의 생물학적 동등성 평가)

  • Noh, Keum-Han;Bae, Kyoung-Jin;Kang, Won-Ku
    • Korean Journal of Clinical Pharmacy
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    • v.19 no.1
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    • pp.61-64
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    • 2009
  • The study was designed to compare the rate and extent of absorption of two enalapril tablets (10 mg), which has been widely used for the treatment of hypertension. This bioequivalence study was conducted using a standard preparation as reference and a generic as test in 24 male healthy volunteers. After an overnight fast, a single dose of the test or reference drugs were given with a washout period of 7 days. Heparinized blood samples were serially collected up to 10 hr. Plasma enalapril concentrations were quantified using a validated LC-MS/MS method. The data obtained for each subject was evaluated for $C_{max}$ and $AUC_{10hr}$ with respect to 90% confidence interval for log-transformed data. The 90% confidence intervals were log(0.9384)~log(1.1160) for $AUC_{10hr}$ and log(0.9482)~log(1.1474) for $C_{max}$. Thus, we concluded that the test and reference formulation are bioequivalent in terms of rate and extent of absorption.

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