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CoMFA vs. Topomer CoMFA, which One is better a Case Study with 5-Lipoxygenase Inhibitors
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.91-98
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4,000원
Quantitative structure-activity relationships (QSAR) have been applied for two decades in the development of relationships between physicochemical properties of chemical substances and their biological activities to obtain a reliable statistical model for prediction of the activities of new chemical entities. The fundamental principle underlying the QSAR is that the structural difference is responsible for the variations in biological activities of the compounds. In this work, we developed 3D-QSAR model for a series of 5-Lipoxygenase inhibitors, utilizing comparative molecular field analysis (CoMFA) and Topomer CoMFA methodologies. Our developed models addressed superiority of Topomer CoMFA over CoMFA. The CoMFA model was obtained with q2=0.593, r2=0.939, Q2=0.334 with 6 optimum number of components (ONC). Higher statistical results were obtained with the Topomer CoMFA model (q2=0.819, r2=0.947, ONC=5). Further robustness of developed models was checked with the ANOVA test and it shows F=113 for CoMFA and F=162.4 for Topomer CoMFA model. Contour map analysis indicated that the more requirement of electrostatic parameter for improved potency.
A Review about the Importance of Protonation of Ionizable Molecules on the Predictability of CoMFA
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.99-102
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4,000원
Effect of protonation and deprotonation of ionization compounds is an important application in Comparative molecular field analysis (CoMFA). There are enough information's were reported about different CoMFA applications such as Series design and selection of training set, Geometries and optimizations of molecules, Effect of partial atomic charges, bioactive conformations and alignment, Interaction energy fields, Effects of different grid spacing etc. However limited information's are available about the ionization of compounds. This study aimed at the critical review of about the effects of protonation of ionizable molecules and its impact on the predictability of CoMFA models. We also discussed about previous implications and the things needed to be considered to come for a final conclusion about its impact on CoMFA predictability.
Effect of Saline Concentrations on Biological Nitrification in Batch Reactor
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.103-112
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4,000원
Pham Tuan Linh2 and Gi Youn Kim This study was carried out on 4 batch reactors to determine the specific ammonium oxidizing rate (SAOR), specific nitrate forming rate (SNFR) and inhibitory degree of nitrifying activities with saline concentrations. Under salt free condition ammonia was consumed during the reaction period within 200 min. When the salt level increased to 10, 20 and 30 g NaClL-1 in reactor, ammonia depletion took 250, 300 and above 350 min, respectively. During concentration above 10 g NaClL-1, there was nitrite accumulation. Also, at 30 g NaClL-1 ammonia did not depleted and NO2 --N accumulated until the final reaction. Nitrate formation rates decreased with increasing salt concentration. SAOR and SNFR showed a decreasing trend as salinity concentrations were increased. The SAOR was reduced from 0.2 to 0.08 mg NH4+-N g-1VSS day-1 as the salt concentration increased from 0 to 30 g NaCLL-1. Similarly, the SNFR decreased from 0.26 kg NO3--N kg-1VSS day-1 at saline free to 0.1 kg NO3--N kg-1VSS day-1 at saline 30 g L-1. A severe inhibition of nitrifiers activity was observed at increased salt concentrations. The inhibition ratio of specific ammonium oxidation rates were 17, 47 and 60% on the reactor of 10, 20 and 30 g NaClL-1 added, respectively. The inhibition ratio of specific nitrate forming rates also were inhibited 30, 53 and 62% on the reactor of 10, 20 and 30 g NaClL-1 added, respectively. As the salinity concentrations increased from 0 to 30 mg NaClL-1, the average MLSS concentration increased from 1,245 to 1,735 mgL-1. The SS concentration of supernatant in reactor which settled about 30 minutes was not severely difference between concentration of salt free reactor and one of those high salt contained reactors.
Loss of Function in GIGANTEA Gene is Involved in Brassinosteroid Signaling
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.113-120
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4,000원
Brassinosteroids (BRs) are plant steroid hormones that play essential roles in growth and development. Mutations in BR-signaling pathways cause defective in growth and development like dwarfism, male sterility, abnormal vascular development and photomorphogenesis. Transition from vegetative to reproductive growth is a critical phase change in the development of a flowering plant. In a screen of activation-tagged Arabidopsis, we identified a mutant named abz126 that displayed longer hypocotyls when grown in the dark on MS media containing brassinazole (Brz), an inhibitor of BRs biosynthesis. We have cloned the mutant locus using adapter ligation PCR walking and identified that a single T-DNA had been integrated into the ninth exon of the GIGANTEA (GI) gene, involved in controling flowering time. This insertion resulted in loss-of-function of the GI gene and caused the following phenotypes: long petioles, tall plant height, many rosette leaves and late flowering. RT-PCR assays on abz126 mutant showed that the T-DNA insertion in GIGANTEA led to the loss of mRNA expression of the GI gene. In the hormone dose response assay, abz126 mutant showed: 1) an insensitivity to paclobutrazole (PAC), 2) an altered response with 6-benzylaminopurine (BAP) and 3) insensitive to Brassinolide (BL). Based on these results, we propose that the late flowering and tall phenotypes displayed by the abz126 mutant are caused by a loss-of-function of the GI gene associated with brassinosteroid hormone signaling.
Estimation of Volatility of Korea Stock Price Index Using Winbugs
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.121-129
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4,000원
The purpose of this paper is to estimate the fluctuation of an earning rate and risk management using the price index of Korea stocks. After an observation of conception of fluctuation, we can show volatility clustering and fluctuation phenomenon in the Korea stock price index using GARCH model with heteroscedasticity. In addition, the effects of fluctuation on the time-series was evaluated, which showed the heteroscedasticity. MCMC method and Winbugs as Bayesian computation were used for analysis.
Adsorption Characteristics of Nickel, Zinc and Cadmium Ions using Alginate Bead
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.130-136
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4,000원
This study investigated the adsorption characteristics of nickel, zinc and cadmium ions from the aqueous solution onto the alginate bead. Adsorption equilibrium capacities of the heavy metal ions increased with increasing initial pH of the solution. The adsorption equilibrium isotherm of the heavy metal ions was well represented by Langmuir equation. The magnitude of adsorption capacity of the heavy metal ions onto alginate bead was the order of cadmium > zinc > nickel. Kinetic parameters were measured in a batch adsorber to analyze the adsorption rates of the heavy metal ions. The internal diffusion coefficient of the heavy metal ions in the intraparticle were determined by comparing the experimental concentration curves with those predicted from the surface diffusion model (SDM) and pore diffusion model (PDM). The internal diffusion of the heavy metal ions in the intraparticles was explained by PDM.
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.137-142
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4,000원
This study was performed in order to examine the statistical quality control of environmentally-friendly agricultural products(EF AP) and they using school meal service whether to be influences to EF AP recognition of it's parents. As a results of above research, we can make a conclusion the elementary and middle school meal service using the EF AP leads to the recognition change to parents affirmatively in Jeollanam-do.
The Comparative Results of Primary School Oral Health Program in Suncheon City
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.143-148
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4,000원
This study was to promote the business of school dental health program in community area and to present the improvement of oral health between public health center's group of SungDong elementary school, one that started on March 1999, and the control group that is going to operate school oral health center from 2009 in primary school. It was based on the data of more than 10 years running school based oral health section. We compared the data of SungDong group with the one of control group to get a survey of dental caries experience. The preventive effect of the caries was estimated by the difference of DMFT indices between the sample group and control group. The experience rate of caries of the sample was 12.6 percentage lower than the control group and index of the experience rate of caries for the SungDong group was two times less. It showed that the sealing rate of the SungDong group composed of pit and fissure sealant was 67.7 percentage high. The prevention rate which was calculated by DMFT index was 46.34 percentage in the SungDong group that was the highest score for the fifth grade student as a 60.5 percentage. This program contributes to the improvement of the dental caries reduction in this school oral health promotion program.
조선대학교 기초과학연구원 통합자연과학논문집(구 조선자연과학논문집) 제4권 2호 2011.06 pp.158-165
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4,000원
Statistics by structural equation modeling techniques were used to assess a model of chemistry learning strategy based on performance goal orientation. In the optimal Model III of this research, Performance-approach goal was positively related to the use of learning strategy(p<.05) and achievement need(p<.05). Performance-avoidance goal was negatively related to learning strategy(p<.05) and was positively related to self-handicapping tendency(p<.15). Performance-approach goal affected learning strategy indirectly through achievement need(p<.05). Use of achievement need was positively related to learning strategy(p<.05) and self-handicapping tendency(p<.35). Self-handicapping tendency affected learning strategy negatively(p<.05). Implications of these findings for learning strategy in chemistry education are discussed.
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