• Archives of Pharmacal Research
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• v.23 no.5
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• pp.507-512
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• 2000

This study set out to improve the physical and pharmaceutical characteristics of the present formulation using an appropriate experimental design. The work described here concerns the formulation of the dispersible tablet applying direct compression method containing roxithromycin in the form of coated granules. In this study $2^3$ factorial design was used as screening test model and Central Composite Design (CCC) associated with response surface methodology was used as optimization study model to develop and to optimize the proper formulation of roxithromycin dispersible tablet. The three independent variables investigated were functional excipients like binder (X1), disintegrant (X2) and lubricant (X3). The effects of these variables were investigated on the following responses: hardness (Y1), friability (Y2) and disintegration time (Y3) of tablet. Three replicates at the center levels of the each design were used to independently calculate the experimental error and to detect any curvature in the response surface. This enabled the best formulations to be selected objectively. The effect order of each term to all response variable was X3> X2> Xl> X1＊X2> X2＊X2> X2＊X3> X3＊X3> Xl＊X3> Xl＊Xl and model equations on each response variables were generated. Optimized compositions of formula were accordingly computed using those model equations and confirmed by following demonstration study. As a result, this study has demonstrated the efficiency and effectiveness of using a systematic formulation optimization process to develop the tablet formulation of roxithromycin dispersible tablet with limited experiment.

• Biomolecules & Therapeutics
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• v.10 no.4
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• pp.293-302
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• 2002

The classical concept for iron uptake into mammalian cells has been the endocytosis of transferrin( $T_{f}$ )-bound F $e^{3+}$ via the $T_{f}$ - $T_{f}$ receptor cycle. In this case, we could not explain the uptake of F $e^{2＋}$ ion and the export of iron from endosome. Studies on iron transport revealed that other transport system exists in epithelial cells of the intestine. One of non- $T_{f}$ -receptor-mediated transport systems is Nramp2/DMT1/DCT1 which transports M $n^{＋＋}$, $Mg^{＋＋}$, Z $n^{＋＋}$, $Co^{＋＋}$, N $i^{＋＋}$ or C $u^{＋＋}$ ion as well as F $e^{+2}$ ion. DMT1 was cloned from intestines of iron-deficient rats and shown to be a hydrogen ion-coupled iron transporter and a protein regulated by absorbed dietary iron. DMT1 is founded in other cells such as cortical and hippocampal glial cells as well as endothelial cells in duodenum. Two F $e^{3+}$ ion bound to transferrin( $T_{f}$ ) are taken up via the $T_{f}$ - $T_{f}$ receptor cycle in the intestinal epithelial cell. F $e^{3+}$ in endosome was converted to F $e^{2＋}$ ion, and then exported to cytosol via DMT1. F $e^{2＋}$ ion is taken up into cytosol via DMT1. Several other transporters such as FET, FRE, CCC2, AFT1, SMF, FTR, ZER, ZIP, ZnT and CTR have been reported recently and dysfunction of the transporters are related with diseases containing Wilson's disease, Menkes disease and hemochromatosis. Evidences from several studies strongly suggest that DMT1 is the major transporter of iron in the intestine and functions critically in transport of other metal ions.

• The Korean Journal of Applied Statistics
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• v.22 no.2
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• pp.261-270
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• 2009

Current financial crisis triggered by shaky U.S. banking system adds to the emphasis on the importance of the volatility in controlling and understanding financial time series data. The ARCH and GARCH models have been useful in analyzing economic time series volatilities. In particular, multivariate GARCH(MGARCH, for short) provides both volatilities and conditional correlations between several time series and these are in turn applied to computations of hedge-ratio and VaR. In this short article, we try to assess various MGARCH models with respect to the back-testing performances in VaR study. To this end, 14 korean stock prices are analyzed and it is found that MGARCH outperforms rolling window, and BEKK and CCC are relatively conservative in back-testing performance.

• Membrane and Water Treatment
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• v.13 no.1
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• pp.29-37
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• 2022

To verify the fate and transport of engineered nanoparticles (ENP), it is essential to understand its interactions with organic matter. Previous research has shown that dissolved organic matter (DOM) can increase particle stability through steric repulsion. However, the majority of the research has been focused on model organic matter such as humic or fulvic acids, lacking the understanding of organic matter found in field conditions. In the current study, organic matter was sampled from wastewater treatment plants to verify the stability of engineered nanoparticles (ENP) under field conditions. To understand how different types of organic matter may affect the fate of ENP, wastewater was sampled and separated based on their size; as small organic particular matter (SOPM) and large organic particular matter (LOPM), and dissolved organic matter (DOM). Each size fraction of organic matter was tested to verify their effects on nano-zinc oxide (nZnO) and nano-titanium oxide (nTiO₂) stability. For DOM, critical coagulation concentration (CCC) experiments were conducted, while sorption experiments were conducted for organic particulates. Results showed that under field conditions, the surface charge of the particles did not influence the stability. On the contrary, surface charge of the particles influenced the amount of sorption onto particulate forms of organic matter. Results of the current research show how the size of organic matter influences the fate and transport of different ENPs under field conditions.

• Journal of Microbiology and Biotechnology
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• v.21 no.2
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• pp.162-169
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• 2011

A dynamic model of lactic acid fermentation using Lactococcus lactis was constructed, and a metabolic flux analysis (MFA) and metabolic control analysis (MCA) were performed to reveal an intensive metabolic understanding of lactic acid bacteria (LAB). The parameter estimation was conducted with COPASI software to construct a more accurate metabolic model. The experimental data used in the parameter estimation were obtained from an LC-MS/MS analysis and time-course simulation study. The MFA results were a reasonable explanation of the experimental data. Through the parameter estimation, the metabolic system of lactic acid bacteria can be thoroughly understood through comparisons with the original parameters. The coefficients derived from the MCA indicated that the reaction rate of L-lactate dehydrogenase was activated by fructose 1,6-bisphosphate and pyruvate, and pyruvate appeared to be a stronger activator of L-lactate dehydrogenase than fructose 1,6-bisphosphate. Additionally, pyruvate acted as an inhibitor to pyruvate kinase and the phosphotransferase system. Glucose 6-phosphate and phosphoenolpyruvate showed activation effects on pyruvate kinase. Hexose transporter was the strongest effector on the flux through L-lactate dehydrogenase. The concentration control coefficient (CCC) showed similar results to the flux control coefficient (FCC).

• Journal of Animal Science and Technology
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• v.55 no.6
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• pp.509-513
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• 2013

We identified molecular markers associated with meat-quality traits in the porcine RPL27A (ribosomal protein L27a) gene. Three single nucleotide polymorphisms (SNPs) were discovered in the porcine RPL27A gene: g.920T>C, g.1013T>C, and g.1046T>C. The g.920 T>C SNP was significantly associated with pH24 (P < 0.05) and collagen (P < 0.05), while the g.1013T>C and g.1046T>C SNPs were significantly associated with moisture (P < 0.05). Either the TTT or CCC haplotype was significantly associated with moisture, pH24 and collagen (P < 0.05, respectively). The genotypes of RPL27A associated with meat-quality traits were all located in intron 2. The three SNPs of the RPL27A found in this study will provide useful information for genetic characterization or association studies of meat-quality traits in other populations. Additionally, these markers could potentially be applied in pig breeding programs to improve meat-quality traits after validation in other populations.

• Asia Marketing Journal
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• v.9 no.3
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• pp.233-255
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• 2007

본 사례는 외환위기 및 대우 그룹 해체로 인해 존폐의 위기에 처했던 대우증권이 선도업체 위상을 탈환하기까지의 재건 과정에서 실행했던 마케팅 전략 및 영업활동을 분석하고 있다. 이를 통해 경영위기를 효과적으로 극복하고 새롭게 도약하기 위해 활용 가능한 마케팅 및 영업 전략의 일례를 소개하고자 한다. 끝으로 대우증권의 향후 마케팅 과제와 관련된 토의 주제가 제시된다. 국내 증권업계 선두주자였던 대우증권은 1999년 '대우 사태'로 인해 한때 업계 5위까지 추락하고 1조 2,000억원의 적자를 기록하였으며 신용등급은 투자부적격 단계인 CCC+까지 하락하는 등 위기를 맞이하게 되었다. 대우증권이 회생과 재도약을 위해 채택한 마케팅 전략은 '선택과 집중'이었다. 즉, 최대 수익원이자 경쟁력이 있는 사업 분야인 위탁매매(brokerage)에 역량을 우선 집중하여 안정적으로 수익 기반을 다진 뒤 이를 바탕으로 IB(Investment Bank)와 자산 관리(Wealth Management) 등 여타 분야에서의 역량도 점진적으로 강화하는 전략이다. 전략의 실행 방향은 높은 효율성 확보 및 자원의 확충을 통해 시장 지배력과 수익성을 창출하는 것이었다. 전략적 공감대, 오프라인 영업 강화, 현장 및 고객 중시를 위한 기업 자원의 확충 배치를 바탕으로 영업 프로세스, 영업 인프라, 영업 관리, 고객 서비스, 영업 문화의 혁신을 실행한 결과, 대우증권은 증권명가의 옛 명성과 위치를 성공적으로 탈환하게 되었다. 대우증권은 2004년 위탁매매 영업 부문에서 1위 위상을 되찾은 이래 전 사업 분야에서 성장을 지속하였다. 2006년 증권업종 시가총액 1위를 회복하는 등 각종 경영지표는 큰 폭으로 개선되었고, 신용등급은 AA-로 상향 조정되었다. 나아가 자본시장통합법 시대에 걸맞는 선도 글로벌 투자은행으로서 진화한다는 계획을 추진하고 있다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.885-894
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• 2006

The purpose of this study is focused on the development of the effective classification technique using ultra multiband of hyperspectral image. This study suggests the classification technique using canonical correlation analysis, one of multivariate statistical analysis in hyperspectral image classification. High accuracy of classification result is expected for this classification technique as the number of bands increase. This technique is compared with Maximum Likelihood Classification(MLC). The hyperspectral image is the EO1-hyperion image acquired on September 2, 2001, and the number of bands for the experiment were chosen at 30, considering the band scope except the thermal band of Landsat TM. We chose the comparing base map as Ground Truth Data. We evaluate the accuracy by comparing this base map with the classification result image and performing overlay analysis visually. The result showed us that in MLC's case, it can't classify except water, and in case of water, it only classifies big lakes. But Canonical Correlation Classification (CCC) classifies the golf lawn exactly, and it classifies the highway line in the urban area well. In case of water, the ponds that are in golf ground area, the ponds in university, and pools are also classified well. As a result, although the training areas are selected without any trial and error, it was possible to get the exact classification result. Also, the ability to distinguish golf lawn from other vegetations in classification classes, and the ability to classify water was better than MLC technique. Conclusively, this CCC technique for hyperspectral image will be very useful for estimating harvest and detecting surface water. In advance, it will do an important role in the construction of GIS database using the spectral high resolution image, hyperspectral data.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.59-64
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• 2000

We performed refraction, keratometry, slit lamp biomicroscopy. We selected 58 current spherical RGP lens wearers for this three-month study. All patients exhibits at least 0.75D of corneal astigmatism measured with the keratometer, and 37 patients had corneal astigmatism of 1.50D or greater. At least follow-up visit, we measured Snellen acuity with lenses, and performed overrefraction, overkeratometry and slit lamp biomicroscopy. We charted lens position, movement and surface quality. During the three month, biomicroscopy revealed no corneal edema and neovascularization on any patients. Fluorescein staining were 52 patients case of grade 0.5 patients case of grade 1, and 1 patient case of grade 2. In evaluating post-fit residual cylinder, on overrefraction as a percentage of refractive cylinder. By the initial visit, one-week visit, one-month visit, and two-month visit are 41%, 34%, 29%, respectively. In this data, we knew no change after one month. The average overrefraction for these eyes in absolute diopters is 0.26D(initial visit), 0.22D(one-week visit, 0.17D(one-month visit), and 0.16D(two-month visit). The use of a regimen containing a dedicated daily cleaner was more effective in maintaining patient comfort and lens cleanliness than was the use of a regimen containing only a multipurpose solution.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.1
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• pp.125-131
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• 1976

To study the effects of temperature, day length, and various plant growth regulator treatments on the tuber formation of Irish cobbler, this experiment was carried out with 2 combinations of day-length and temperature and 11 kinds of growth regulator, including GA, and their combinations. For the tuber formation, low temperature-short day condition played decisive role, and exceeded the effects of growth regulators. 4 times foliar application of 10 ppm GA resulted marked elongation of stolon but did not inhibit the tuber formation even under high temperature longday condition.