• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.421-427
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• 2016

Nanosized hollow silica was prepared by $St{\ddot{o}}ber$ method in the presence of aluminum isopropoxide. The mixture of polyelectrolytes such as poly(sodium 4-styrene sulfonate)(PSS) and polyacrylic acid(PAA) were used as templates. Tetraethylorthosilicate(TEOS) and aluminum isopropoxide were used as precursors for silica and alumina, respectively. The function of aluminum isopropoxide is to increase the porosity of silica shell. The characterizations of hollow silica were examined by TEM(transmission electron microscopy), TGA(thermogravimetric analysis), BET(Brunauer Emmett Teller), Energy-dispersive X-ray spectroscopy(EDS), and FT-IR spectrum. It was found that the shell thickness of hollow silica was around 8 nm and the core diameter was around 20 nm by TEM.

• Toxicological Research
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• v.4 no.1
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• pp.37-45
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• 1988

Primary cultures of adult rat hepatocytes were used to study in vitro cytotoxic effects of T-2 toxin on liver cells. When T-2 toxin was added to the culture, a significant depression of the hormonal induction of ${\alpha}$-aminoisobutyric acid (AIB) uptake and tyrosine aminotransferase (TAT) activity was observed. However, T-2 toxin did not affect the uptake of ouabain into hepatocytes. Protein synthesis was inhibited by T-2 toxin, but RNA synthesis was not severely affected. The inhibitory effects of T-2 toxin on protein synthesis was diminished rapidly with culture time and the hepatocytes culture maintained control level of protein synthesis within 24 hrs.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.457-458
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• 2001

To determine the effect of ERp57 expression on thrombopoiein (TPO) productivity in recombinant Chinese hamster ovary (rCHO) cells, TPO producing rCHO cell line with doxycycline-regulated ERp57 expression \Vas developed. The Erp57 expression level could be regulated by addition of different concentrations of doxycycline to culture medium. The doxycycline concentration of I ${\mu}g/mL$ was high enough to suppress the ERp57 expression. Up to 5 ${\mu}g/mL$ doxycycline concentration used in culture medium, no observable cytotoxic effect of doxycycline was detected during culture. Overexpression of ERp57 、 vas found to increase the specific TPO productivity ($q_{Tpo}$) without growth inhibition, probably due to the chaperone-like activity of ERp57 in CHO cells.

• KSBB Journal
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• v.19 no.5
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• pp.390-393
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• 2004

Oxygen uptake rate (OUR) was used as an indicator of microbial activity. In this study OUR at dyeing wastewater in the pilot plant was monitored to examine biological activity. Correlation between inlet COD concentration and maximum OUR showed that maximum OUR was proportional to inlet COD concentration. Changes in the OUR values reflected the changing waste load in the reactor. Consequently, OUR can be used to estimate biological activity of inlet COD concentration. This study showed that biodegradable COD at dyeing wastewater could be calculated from OUR and yield coefficient. Non-biodegradable COD was able to be calculated from a difference between initial COD concentration and biodegradable COD.

• Genomics & Informatics
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• v.10 no.1
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• pp.44-50
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• 2012

Pattern discovery in biological sequences (e.g., DNA sequences) is one of the most challenging tasks in computational biology and bioinformatics. So far, in most approaches, the number of occurrences is a major measure of determining whether a pattern is interesting or not. In computational biology, however, a pattern that is not frequent may still be considered very informative if its actual support frequency exceeds the prior expectation by a large margin. In this paper, we propose a new interesting measure that can provide meaningful biological information. We also propose an efficient index-based method for mining such interesting patterns. Experimental results show that our approach can find interesting patterns within an acceptable computation time.

• Journal of Environmental Science International
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• v.6 no.2
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• pp.107-112
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• 1997

The purpose of this study was to examine the questioning styles in middle school environmentology textbook In terms of frequency, type, and placement of questions. It was also to analyse and to compare the kinds of scientific inquiry processes elicited by the questions in the topics of textbooks. The instrument was the Textbook Questing Strategies Assessment Instrument (TQSAI) developed the Cooperative Teacher Preparation Project, University of California. The average number of Questions per topic was only 1.09 and the ratio of questions to sentences was 2.5%. Most of questions were in explanatory place(75%). Nearly 90% of experienced questions types were reasoning or application. The frequencies of non-experiential question were higher than those of experiential question. In action, there were much kinds of question-styles.

• KSBB Journal
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• v.23 no.5
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• pp.449-451
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• 2008

Ceramide has become a widely used ingredient in cosmetic and pharmaceutical industries, however, only a few yeast strains were investigated for the synthesis of ceramide and the concentration was very low. Ceramide is not only a core intermediate of sphingolipids but also an important modulator of many cellular events including apoptosis, cell cycle arrest, senescence, differentiation, and stress responses. In this study S.cerevisiae was grown in a batch culture and the cellular content of ceramide was measured at different growth phases. The ceramide content was highest at stationary phase and 2.01 mg ceramide/g cell was obtained.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.749-756
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• 2000

Chemical application, one of the most important crop management processes happened to cause spray drift, that would threaten farmers in field as well as dwellers in rural region. Spray drift was affected by micro-meteorological parameters. In Korea, a boom sprayer was introduced but good effects of a boom sprayer was not evaluated. A study to evaluate short distance drift characteristics of a boom sprayer in paddy fields has been undergoing and determining wind characteristics in paddy field was the main purpose of this paper. Micro-meteorological information has been pre-requisite information for evaluating drift in both long and short distances or in both theoretical and experimental ways. Wind velocity, Reynolds stresses, turbulence intensity, skewness, kurtosis etc. were evaluated with height from the ground using a 2-dimensional probe and a hot wire anemometer system.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.593-599
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• 2000

Accurate quantification of plant physiological properties is often necessary for optimal control of an automated greenhouse production system. Conventional crop growth monitoring systems are usually burdensome, inaccurate, and harmful to crops. A thermal image analysis system was used to accomplish rapid and accurate measurements of physiological-property changes of water-stressed crops. Thermal images were obtained from several species of plants that were placed in a growth chamber. Analyzing the images provided the pattern of temperature changes in a leaf and the amount of differences in the temperature of stressed plants and non-stressed plants.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.836-839
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• 2000

Beef tallow, which is an industrial lipid substrate, was hydrolyzed by lipase immobilized on a high-density polyethylene (HDPE) powder. Ethanol pre-washing process affected the immobilization efficiency. Half-life of storage of the HDPE at $4^{\circ}C$ was 150 days. And after 10 times of repeated use, more than 50% of initial activity remained. An apparent Michaelis constant ($K_m$) and maximum velocity ($V_{max}$) were 2.7M, and 1.4 mmol/min/l for immobilized lipase, and 0.5 M, and 1.9 mmol/min/l for soluble lipase, respectively.