• Biomolecules & Therapeutics
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• v.23 no.2
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• pp.189-194
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• 2015

P450 1A2 is responsible for the metabolism of clinically important drugs and the metabolic activation of environmental chemicals. Genetic variations of P450 1A2 can influence its ability to perform these functions, and thus, this study aimed to characterize the functional significance of three P450 1A2 allelic variants containing nonsynonymous single nucleotide polymorphisms (P450 $1A2^*8$, R456H; $^*15$, P42R; $^*16$, R377Q). Variants containing these SNPs were constructed and the recombinant enzymes were expressed and purified in Escherichia coli. Only the P42R variant displayed the typical CO-binding spectrum indicating a P450 holoenzyme with an expression level of ~ 170 nmol per liter culture, but no P450 spectra were observed for the two other variants. Western blot analysis revealed that the level of expression for the P42R variant was lower than that of the wild type, however the expression of variants R456H and R377Q was not detected. Enzyme kinetic analyses indicated that the P42R mutation in P450 1A2 resulted in significant changes in catalytic activities. The P42R variant displayed an increased catalytic turnover numbers ($k_{cat}$) in both of methoxyresorufin O-demethylation and phenacetin O-deethylation. In the case of phenacetin O-deethylation analysis, the overall catalytic efficiency ($k_{cat}/K_m$) increased up to 2.5 fold with a slight increase of its $K_m$ value. This study indicated that the substitution P42R in the N-terminal proline-rich region of P450 contributed to the improvement of catalytic activity albeit the reduction of P450 structural stability or the decrease of substrate affinity. Characterization of these polymorphisms should be carefully examined in terms of the metabolism of many clinical drugs and environmental chemicals.

• Advances in Traditional Medicine
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• v.8 no.2
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• pp.164-170
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• 2008

The hepatoprotective activity of the alcoholic extract of Rosa damascena was studied against paracetamol induced acute hepatotoxicity in rats. Liver damage was assessed by estimating serum enzyme activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and histopathology of liver tissue. Pre- and post-treatment with ethanolic extracts showed a dose-dependent reduction of paracetamol induced elevated serum levels of enzyme activity. The mechanism underlying the protective effects was assayed in vitro and the R. damascena extracts displayed dosedependent free radical activity using DPPH ($IC_{50}=162.525\;{\mu}g/ml$) and TBA method. The hepatoprotective action was confirmed by histopathological observation. The ethanolic extracts reversed paracetamol induced liver injury. These results suggest that the hepatoprotective effects of R. damascena extracts are related to its antioxidative activity.

• BMB Reports
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• v.39 no.2
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• pp.167-170
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• 2006

Bovine adenosine deaminase undergoes a nondenaturational conformational change at $29^{\circ}C$ upon heating which is characterized by a large increase in heat capacity. We have determined the transition state thermodynamics of the conformational change using a novel application of differential scanning calorimetry (DSC) which employs very slow scan rates. DSC scans at the conventional, and arbitrary, scan rate of $1^{\circ}C/min$ show no evidence of the transition. Scan rates from 0.030 to $0.20^{\circ}C/min$ reveal the transition indicating it is under kinetic control. The transition temperature $T_t$ and the transition temperature interval ${\Delta}T$ increase with scan rate. A first order rate constant $k_1$ is calculated at each $T_t$ from $k_1\;=\;r_{scan}/{\Delta}T$, where $r_{scan}$ is the scan rate, and an Arrhenius plot is constructed. Standard transition state analysis reveals an activation free energy ${\Delta}G^{\neq}$ of 88.1 kJ/mole and suggests that the conformational change has an unfolding quality that appears to be on the direct path to the physiological-temperature conformer.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06a
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• pp.170-173
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• 2011

본 논문에서는 모바일 소프트웨어 플랫폼 유지 보수성 개선 목표로 수행된 리엔지니어링 (Reengineering) 사례를 소개한다. 모바일 소프트웨어 플랫폼은 높아진 사용자 기능 요구 같은 대외적인 문제와 다양한 서비스 경쟁력 확보를 위한 제조사 내부적인 노력으로 인해 소프트웨어 규모와 복잡도가 급격히 증가하고 있는 상황이다. 기반 시스템으로서 모바일 소프트웨어 플랫폼은 기존 레거시(legacy) 시스템을 재사용하여 상품화를 수행하는 일반 임베디드 시스템 개발 특징과 이동 통신 사업자 요구사항 대응, 다양한 시장 및 다양한 하드웨어 빛 표준화 대응, 다양한 도메인 (domain) 이 하나의 기기에서 통합된 형태로 동작해야 한다는 점에서 다른 임베디드 시스템과 차별화된다고 볼 수 있다. 모바일 소프트웨어 플랫폼을 대상으로 한 성공적인 리엔지니어링 수행은 기반 시스템의 유지보수성 향상은 물론 연간 수십 개에 달하는 파생 시스템의 재사용성 및 생산성 향상을 기대할 수 있다. 본 연구에서는 사내 표준 프로세스를 재정의하고, 모바일 소프트웨어 플랫폼만의 특성을 고려하여 수행한 리엔지니어링 사례를 소개하고자 한다.

• Environmental Engineering Research
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• v.25 no.2
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• pp.163-170
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• 2020

Knowledge of organic micropollutant transfers in barrier seal materials from waste storage facilities is limited to volatile organic compounds and phenolic compounds at ambient temperature. This study focused on the sorption of chlorophenols (CPs) from various geotextiles from clay geosynthetics under the influence of temperature. Also to study the impact of the polarity or the amount of CPs adsorbed on geotextiles with the partition coefficient. The effect of various parameters such as contact time, effect of temperature, initial CPs concentration and adsorbent dosage has been carried out in this study. The result obtained is non-linear and the data was calculated for affinity with Freundlich isotherm model. An important observation is that the amount of CPs sorbed on geotextiles increases with a growing number of chlorine atoms, ie increases with the partition coefficient (log K_ow). During this study, a decrease in adsorbent properties was observed with the rise in temperature from 23℃ to 55℃. The partitioning coefficients for CPs examined range are from 2.4 (R² = 0.86) to 8.4 mL/g (R² = 0.90). Among the CPs studied, the highest adsorbed quantity was observed for pentachlorophenol with 0.052 g/g at 23℃, this quantity will decrease with the increase in temperature.

• Journal of Species Research
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• v.6 no.2
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• pp.163-170
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• 2017

As a part of the research program 'Survey of freshwater organisms and specimen collection', freshwater samples were collected from Lakes Soyang and Chungju in 2016. Hundreds of bacterial strains were isolated from the samples and were identified based on 16S rRNA gene sequences. Among the bacterial isolates, strains showing higher than 98.7% sequence similarity with validly published bacterial species not reported in Korea were selected as unrecorded bacterial species. Based on 16S rRNA gene sequence similarity, 17 strains were identified as unrecorded bacterial species in Korea. The 17 bacterial strains were phylogenetically diverse and belonged to four phyla, seven classes, 13 orders, 14 families, and 16 genera. At generic level, the unreported species were affiliated with Caulobacter, Paracoccus, and Mesorhizobium of the class Alphaproteobacteria, Deefgea, Undibacterium, Chitinimonas, Inhella, and Sphaerotilus of the class Betaproteobacteria, Vibrio and Cellvibrio of the class Gammaproteobacteria, Sanguibacter and Clavibacter of the phylum Actinobacteria, Lactococcus of the phylum Firmicutes, Deinococcus of the class Deinococci, and Chryseobacterium and Flavobacterium of the phylum Bacteroidetes. The unreported species were further characterized by examining Gram reaction, colony and cell morphology, biochemical properties, and phylogenetic position. The detailed description of the 17 unreported species are also provided.

• Advances in nano research
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• v.2 no.2
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• pp.99-109
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• 2014

Experiments are performed to investigate the single-phase flow heat transfer augmentation of MWCNT/HT-B Oil in both smooth and micro-fin helical tubes with constant wall temperature. The tests in laminar regime were carried out in helical tubes with three curvature ratios of 2R/d=22.1, 26.3 and 30.4. Flow Reynolds number varied from 170 to 1800 resulting in laminar flow regime. The effect of some parameters such as the nanoparticles concentration, the dimensionless curvature radius (2R/d) and the Reynolds number on heat transfer was investigated for the laminar flow regime. The weight fraction of nanoparticles in base fluid was less than 0.4%. Within the applied range of Reynolds number, results indicated that for smooth helical tube the addition of nanoparticles to the base fluid enhanced heat transfer remarkably. However, compared to the smooth helical tube, the average heat transfer augmentation ratio for finned tube was small and about 17%. Also, by increasing the weight fraction of nanoparticles in micro-fin helical tubes, no substantial changes were observed in the rate of heat transfer enhancement.

• Journal of The Korean Association For Science Education
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• v.32 no.8
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• pp.1378-1389
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• 2012

Environmental education is usually taught across the curriculum in most of the countries. This teaching approach has been a challenge for teachers to implement it especially in the Malaysian curriculum context. Thus, science teachers require effectual Pedagogical Content Knowledge of Environmental Education (PCK-EE). The purpose of this study was to explore the influence of teaching option and teaching experience on science teachers' PCK-EE. Five components of PCK-EE were investigated in this study, which were: a) knowledge of curriculum, b) knowledge of content, c) knowledge of student, d) knowledge of teaching strategies, and e) knowledge of evaluation. 347 secondary science teachers from the state of Selangor have participated in this survey study. The questionnaire used had 60 items. The findings revealed teaching option has a significant influence on science teachers' knowledge of content (p=0.000); knowledge of student (p=0.000) and knowledge of teaching strategies (p=0.016). In the case of teaching experience, it was found that there is a low correlation on knowledge of content (r=0.174) and knowledge of evaluation (r=0.170) only. Implication of this study leads to the suggestion in enhancing teachers' service training to improve their PCK-EE and subsequently their ability in teaching environmental education across curriculum.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.3
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• pp.619-629
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• 2016

This study was a descriptive study to investigate emotional labor, clinical practice stress and satisfaction of clinical practice in nursing college students. The data were collected using an self-reporting questionnaire from June 1 to July 12, 2015. Collected data were analysed on SPSS Win 20.0. The study results were summarized as follows : The students' emotional labor was $3.13{\pm}0.54$ in average on a scale of 5. The clinical practice stress was $3.65{\pm}0.47$ in average, and students' satisfaction of clinical practice was $3.41{\pm}0.43$. The emotional labor has positive correlation significantly with clinical practice stress(r=0.353, p<.001), and negative correlation with satisfaction of clinical practice (r=-0.170, p<.007). In stepwise multiple regression to put control variables, emotional labor and clinical practice stress were no significant influence toward satisfaction of clinical practice. According the result, to improve the satisfaction of clinical practices emotional labor should be released. Moreover it is necessary to attention to the health care of nursing students and it is needed to boost up the students satisfaction with major, more friendly relations should be built with co-trainees.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.166-170
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• 1999

The identification of quantitative trait loci (QTL) has the potential to enhance the efficiency of im- proving food processing traits of soybean. In this study, 92 restriction fragment length polymorphism (RFLP) loci and two morphological markers (W$_1$ and T) were used to identify QTL associated with food processing traits of soybean for sprout in 83 F$_2$-derived lines from a cross of ＇Pureun＇ x ＇Jinpum 2＇. The genetic map consisted of 76 loci which covered about 760 cM and converged into 20 linkage groups. Eighteen markers remained unlinked. Phenotypic data were collected for hypocotyl length, abnormal seedling rate, and sprout yield seven days after seed germination at 2$0^{\circ}C$. Based on the single-factor analysis of variance, eight independent markers were associated with hypocotyl length. Four of seven markers associated with abnormal seedling rate were identified as independent. Seven loci were associated with sprout yield. For three different traits, much of genetic variation was explained by the identified QTL in this population. Several RFLP markers in linkage group (LG) Bl were detected as being associated with three traits, providing a genetic explanation for the biological correlation of sprout yield with hypocotyl length (r=OA07＊＊＊) and with abnormal seedling rate (r=-406＊＊＊).