• Journal of Life Science
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• v.32 no.11
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• pp.872-881
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• 2022

In this study, we optimized the composition of the indole-3-acetic acid (IAA) production medium using response surface methodology on Pantoea agglomerans SRCM 119864 isolated from soil. IAA-producing P. aglomerans SRCM 119864 was identified by 16S rRNA gene sequencing. There are 11 intermediate components known to affect IAA production, hence the effect of each component on IAA production was investigated using a Plackett-Burman design (PBD). Based on the PBD, sucrose, tryptone, and sodium chloride were selected as the main factors that enhanced the IAA production at optimal L-tryptophan concentration. The predicted maximum IAA production (64.34 mg/l) was obtained for a concentration of sucrose of 13.38 g/l, of tryptone of 18.34 g/l, of sodium chloride of 9.71 g/l, and of L-tryptophan of 6.25 g/l using a the hybrid design experimental model. In the experiment, the nutrient broth medium supplemented with 0.1% L-tryptophan as the basal medium produced 45.24 mg/l of IAA, whereas the optimized medium produced 65.40 mg/l of IAA, resulting in a 44.56% increase in efficiency. It was confirmed that the IAA production of the designed optimal composition medium was very similar to the predicted IAA production. The statistical significance and suitability of the experimental model were verified through analysis of variance (ANOVA). Therefore, in this study, we determined the optimal growth medium concentration for the maximum production of IAA, which can contribute to sustainable agriculture and increase crop yield.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.2
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• pp.157-178
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• 2013

This study gives a conceptual and basic direction to develop a URL (underground research laboratory) program for establishing the performance and safety of a deep geological disposal system in Korea. The concept of deep geological disposal is one of the preferred methodologies for the final disposal of spent nuclear fuel (SNF). Advanced countries with radioactive waste disposal have developed their own disposal concepts reasonable to their social and environmental conditions and applied to their commercial projects. Deep geological disposal system is a multi-barrier system generally consisting of an engineered barrier and natural barrier. A disposal facility and its host environment can be relied on a necessary containment and isolation over timescales envisaged as several to tens of thousands of years. A disposal system is not allowed in the commercial stage of the disposal program without a validation and demonstration of the performance and safety of the system. All issues confirming performance and safety of a disposal system include investigation, analysis, assessment, design, construction, operation and closure from planning to closure of the deep geological repository. Advanced countries perform RD&D (research, development & demonstration) programs to validate the performance and safety of a disposal system using a URL facility located at the preferred rock area within their own territories. The results and processes from the URL program contribute to construct technical criteria and guidelines for site selection as well as suitability and safety assessment of the final disposal site. Furthermore, the URL program also plays a decisive role in promoting scientific understanding of the deep geological disposal system for stakeholders, such as the public, regulator, and experts.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1404-1410
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• 2012

In vitro experiments were conducted to evaluate the suitability of several mixtures of high tanniniferous non legumes with low tanniniferous legumes on in vitro gas production (IVGP), dry matter degradation, Ammonia-N, methane production and microbial population. Eight treatments were examined in a randomized complete block design using four non-legumes and two legumes (Carallia integerrima${\times}$Leucaena leucocephala (LL) (Trt 1), C. integerrima${\times}$Gliricidia sepium (GS) (Trt 2), Aporosa lindeliyana${\times}$LL (Trt 3), A. lindeliyana${\times}$GS (Trt 4), Ceiba perntandra${\times}$LL (Trt 5), C. perntandra${\times}$GS (Trt 6), Artocarpus heterophyllus${\times}$LL (Trt 7), A. heterophyllus${\times}$GS (Trt 8). The condensed tannin (CT) content of non legumes ranged from 6.2% (Carallia integerrima) to 4.9% (Ceiba perntandra) while the CT of legumes were 1.58% (Leucaena leucocephala) and 0.78% (Gliricidia sepium). Forage mixtures contained more than 14% of crude protein (CP) while the CT content ranged from 2.8% to 4.0% respectively. Differences (p<0.05) were observed in in vitro gas production (IGVP) within treatments over a 48 h period dominated by C. perntandra${\times}$G. sepium (Trt 6). The net gas production (p<0.05) was also high with Trt6 followed by A. heterophyllus${\times}$L. leucocephala (Trt 7) and A. heterophyllus${\times}$G. sepium (Trt 8). Highest (p>0.05) NH3-N (ml/200 mg DM) production was observed with the A. heterophyllus${\times}$G. sepium (Trt 8) mixture which may be attributed with it's highest CP content. The correlation between IVGP and CT was 0.675 while IVGP and CP was 0.610. In vitro dry matter degradation (IVDMD) was highest in Trt 8 as well. Methane production ranged from 2.57 to 4.79 (ml/200 mg DM) to be synonimous with IVGP. A higher bacteria population (p<0.05) was found in C. perntandra${\times}$G. sepium (Trt 6) followed by Artocarpus heterophyllus+G. sepium (Trt 8) and the same trend was observed with the protozoa population as well. The results show that supplementing high tannin non leguminous forages by incremental substitution of legume forage increased gas production parameters, NH3-N, IVDMD and microbial population in the fermentation liquid. Methane production was not significantly affected by the presence of CT or different levels of CP in forage mixtures. Among non legumes, Ceiba perntandra and Artocarpus heterophyllus performed better in mixture with L. leucocephala and G. sepium.

• Journal of The Korean Association For Science Education
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• v.40 no.3
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• pp.347-358
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• 2020

He purpose of this study is to design and apply a pilot assessment tools for scientifically gifted and talented elementary school students with lower grades. The assessment tool consists of three parts: homeroom teachers' recommendation, paper and pencil test and performance tests. The tools are verified whether they are suitable for unique characteristics of young children and enable to attract active participation. For suitability check, students' performance tests were inductively analyzed and 30 behavioral patterns were shown which were included and partially exceeded the level of lower elementary students' performance expectation in NGSS. As a result, we concluded that assessment tool developed in this study will be effective in discriminating young pupils' scientific talents. Then for participation check, we compared the number of coding references as an indicator of participation. Two cases were found that students with high interest participated passively in performance tests. We found these 'passive participants' had excessive scientific experiences and extremely narrow region of interest, during the process of complex interpretation between the results of this assessment tool and in-depth interviews with homeroom teachers. We found out in this study that newly developed tools can be used in school scene after modifying and elaboration through accumulation of more case studies.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.1
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• pp.66-73
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• 2015

Alveolar bone loss and deformation can be a risk factor in removable prosthetic restoration treatment for partially or fully edentulous patients. The use of implants to solve this problem could improve the support, retention and stability of removable restoration. Attachments used in implant overdenture are versatile. The attachment should be selected according to the patients' conditions. Milled bar has been chosen when readymade bar could not be used because of the narrow distance between implants or firm stability and support of supra-structure were needed. Milled bar design is able to provide cross arch stabilization and comfortability to patients. However, it needs skilled laboratory procedures. Recently, the fabrication of milled bar has become simple and its suitability has been improved through the development of CAD/CAM system. In a 67-year-old female Alzheimer's disease patient with 8 implant fixtures on the fully edentulous site of mandible, implant overdenture with using milled bar and magnet attachment was planned. As rapid treatment was required, CAD/CAM system was used to make a simple laboratory procedure instead of a traditional fabrication process. With this system, implant overdenture with milled bar can be fabricated esthetically and functionally.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.4 s.117
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• pp.69-83
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• 2006

Nature rehabilitation has become a major theme in river management in South Korea. An analysis and evaluation of the landscape is a crucial step to select the suitable tracts for developing or conserving land use in the process of landscape planning. The purpose of this paper is to establish a hierarchical procedure for the setting of the landscape units on the various scales at which field biologists performed their observations and to select the preserves through by a suitability model for synthesizing the ecological empirical, and biophysical data. An evaluation process needs to be performed according to the landscape scales: site, local, and regional scales, at which the environmental data were collected, analyzed, and synthesized. Introducing of three level scales was crucially necessary for evaluating the various multi level ecological data for zoning of preserves in river corridors. The evaluation level at different scales are hierarchically established into three phases. The first evaluation phase can be performed by the long length units defined by the ranges of stream widths at regional scale. Secondly, each of these long units can be divided into two or more segments according to its landscape homogeneity at local level. Finally the segments at the last phase can be designated according to the location of the reservoir weirs and bridges at site level. The conceptual model components are adopted for collecting, evaluating, and interpreting the biological and abiotic data at site level. Three preserves are selected, having high potentials for being intensely managed as the Ecological Education Areas in the river. Despite a lot of assumption the results are expected to facilitate discussion and decision making about which frameworks of evaluation are desirable and adaptable for integrating the ecological data into the rehabilitation design process in South Korea.

• Journal of Korean Society of Steel Construction
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• v.25 no.3
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• pp.289-297
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• 2013

In this study, the local buckling behavior of steel built-up columns, fabricated with grade 800MPa high performance (HSA800), was investigated to verify the suitability of width-to-thickness ratio limits adopted by the current design code. For this purpose, an experimental program was designed and performed for HSA800 steel column specimens with various width-to-thickness ratios. Then the experimental results were compared and verified with finite element analysis results. The parametric analytical studies with various width-to-thickness ratios were also performed to investigate the missing data from the limited experimental studies. From the experimental and analytical studies, It was found that the finite analysis models could reasonably estimate the test results within the 5.3% average differences. The local buckling behaviors of HSA800 steel columns were found to be largely depend on the values of initial imperfection introduced into finite element analyses.

• Journal of Pharmaceutical Investigation
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• v.35 no.3
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• pp.137-142
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• 2005

A rapid, selective and sensitive reversed-phase HPLC method for the determination of glipizide in human serum was validated and applied to the pharmacokinetic study of glipizide. Glipizide and internal standard, tolbutamide, were extracted from human serum by liquid-liquid extraction with benzene and analyzed on a Nova Pak $C_{18}\;60{\AA}$ column with the mobile phase of acetonitrile-potassium dihydrogen phosphate (10 mM, pH 3.5) (4:6, v/v). Detection wavelength of 275 nm and flow rate of 0.7 ml/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^3$ factorial design using a fixed glipizide concentration (500 ng/ ml) with respect to its peak area and retention time. And also, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of 10-1000 ng/ml with correlation coefficient greater than 0.999. The lower limit of quantitation using 0.5 ml of serum was 10.0 ng/ml, which was sensitive enough for pharmacokinetic studies. The overall accuracy of the quality control samples ranged from 82.6 to 105.0% for glipizide with overall precision (% C.V.) being 1.13-13.20%. The percent recovery for human serum was in the range of 85.2 93.5%. Stability studies showed that glipizide was stable during storage, or during the assay procedure in human serum. The peak area and retention time of glipizide were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of glipizide in human serum samples for the pharmacokinetic studies at three different laboratories, demonstrating the suitability of the method.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.437-443
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• 2005

A rapid, selective and sensitive reversed-phase HPLC method for the determination of a major metabolite of terfenadine, fexofenadine, in human serum was developed, validated, and applied to the pharmacokinetic study of terfenadine. Fexofenadine and internal standard, haloperidol were extracted from human serum by liquid-liquid extraction with acetonitrile and analyzed on a $Symmetry^{TM}$ C8 column with the mobile phase of 1% triethylamine phosphate (pH 3.7)-acetonitrile (67:33, v/v, adjusted to pH 5.6 with triethylamine). Detection wavelength of 230 nm for excitation, 280 nm for emission and flow rate of 1.0 mL/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^{3}$ factorial design using a fixed fexofenadine concentration (50 ng/mL) with respect to its peak area and retention time. In addition, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of 10-500 ng/mL with correlation coefficients greater than 0.999. The lower limit of quantification using 0.5 mL of serum was 10 ng/mL, which was sensitive enough for the pharmacokinetic studies of terfenadine. The overall accuracy of the quality control samples ranged from 95.70 to 114.58% for fexofenadine with overall precision (% C.V.) being 3.53-14.39%. The relative mean recovery of fexofenadine for human serum was 90.17%. Stability studies (freeze-thaw, short-term, extracted serum sample and stock solution) showed that fexofenadine was stable during storage, or during the assay procedure in human serum. However, the storage at $-70^{\circ}C$ for 4 weeks showed that fexofenadine was not stable. The peak area and retention time of fexofenadine were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of fexofenadine in human serum samples for the pharmacokinetic studies of orally administered Tafedine tablet (60 mg as terfenadine) at three different laboratories, demonstrating the suitability of the method.

• Journal of Pharmaceutical Investigation
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• v.35 no.4
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• pp.265-271
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• 2005

A rapid, selective and sensitive reversed-phase HPLC method for the determination of etodolac in human serum was developed, validated, and applied to the pharmacokinetic study of etodolac. Etodolac and internal standard, ibuprofen were extracted from human serum by liquid-liquid extraction with hexane/isopropanol (95:5, v/v) and analyzed on a Luna C18(2) column with the mobile phase of 1% aqueous acetic acid-acetonitrile (4:6, v/v). Detection wavelength of 227 nm and flow rate of 1.0 mL/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^3$ factorial design using a fixed etodolac concentration $(1\;{\mu}g/mL)$ with respect to its peak area and retention time. And also, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of $0.05-40\;{\mu}g/mL$ with correlation coefficients greater than 0.999. The lower limit of quantification using 0.5 mL of serum was 0.05 ${\mu}g/mL$, which was sensitive enough for pharmacokinetic studies. The overall accuracy of the quality control samples ranged from 92.00 to 110.00% for etodolac with overall precision (% C.V.) being 1.08-10.11%. The percent recovery for human serum was in the range of 76.73-115.30%. Stability studies showed that etodolac was stable during storage, or during the assay procedure in human serum. The peak area and retention time of etodolac were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of etodolac in human serum samples for the pharmacokinetic studies of orally administered Lodin XL tablet (400 mg as etodolac) at three different laboratories, demonstrating the suitability of the method.