• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.224-227
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• 2002

Colistin produced from Penibacillius polymyxa was widely used as an antibiotic active against gram-negative bacteria and as feed additive. This research studied on increment of colistin productivity by mutation of P. polymyxa. As a result, several mutants were obtained from the strain by UV radiation and NTG treatment. They produced approximately 8.5${\sim}$9.0 g/L of colistin in flask and jar culture. Colistin productivity of the mutant, named Penibacillius polymyxa CBY, showed 100 times than that of wild type. When Penibacillius polymyxa CBY fermented in the optimal medium, it produced up to 18 g/L of colistin in jar fermentation.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.176-179
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• 2003

Fuel oxygenates, such as Methyl tertiary Butyl Ether (MTBE) is additive in gasoline used to reduce air pollution. Gasoline components and fuel additives can leak form underground storage tanks. MTBE is far more water soluble than gasoline hydrocarbons like BTEX then it travels at essentially the same velocity as groundwater. MTBE in drinking water causes taste and odor problems. Therefore, the purpose of the this study is to examine the ability of ground rubber to sorb MTBE form water. The study consisted of running both batch and column tests to determine the sorption capacity and the flow through utilization efficiency of ground rubber. The result of Column test indicate that ground tire rubber has on the 36% utilization rate. Finally, it is clear that ground rubber present an attractive and relatively inexpensive sorption medium for a MTBE. The Author thought that to determine the economic costs of ground rubber utilization, the cost to sorb a given mass of contaminant by ground rubber will have to be compared to currently accepted sorption media.

• Journal of Science of Art and Design
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• v.2
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• pp.90-127
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• 2000

The Paper aims to survey and analyze the meaning 'Absence of body' from clothes as non-verbal communication medium. Two types of absence of body from clothes are clothes as object because of removing body, and flattened colthes to deny the body form. In results of analysis, 1)the confrontation of male/female was represented by positive/negative, active/passive, present/absent. 2) male/female means social/private, body/clothing, relevant/irrelevant, subjective/additive. 3) one/numbers, simple/various, limited/free present the various way of waering. 4) tradition/contemporary is expressed by materials 5) enlarged clothes expresses the cynical attitude about body 6) inside/outside , one dress/layered dress suggest new concept to wear against traditional way of wearing.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.893-895
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• 2009

In this paper, we described the unique and novel method to prepare two kinds of electro-active particles, black and white particles with different polarity. The surface of the particles was characterized to be uniform and clean by adopting spray dryer as a tool for genesis of particles; neither surfactants nor high dielectric medium like water was employed during particle preparation step. The other purpose of this study is to investigate the factors that contribute high driving voltage of particlebased display like QR-LPD. We extracted parameters interaction between particle and electrode, and between oppositely charged particles. Here we reported an excellent behavior of particle-based display that showed low operating voltage, high contrast ratio as high as 8:1 without scarification of quick response time. By optimizing the particle size, charge per mass, selection of external additive sets, a lower driving voltage as low as 40V for the particles with $10{\mu}m$ volume average diameter was obtained.

• Natural Product Sciences
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• v.22 no.2
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• pp.134-139
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• 2016

Phytochemicals were isolated from leaves of the fiber crop, ramie (Boehmeria nivea, Bn), using open column chromatography and medium pressure liquid chromatography. Their structures were identified as ${\beta}$-sitosterol, (-)-loliolide, rutin, and pyrimidinedione by MS, $^1H$-, and $^{13}C$-NMR spectroscopic analysis. Among them, (-)-loliolide was isolated for the first time from B. nivea. A content analysis of (-)-loliolide in B. nivea collected from different regions and harvest times was conducted by HPLC. The highest content of (-)-loliolide was found in Bn-23 harvested in September. These results will be helpful to use the plant which harvest in September as a high content phytochemical additive in food, health supplements, and medicinal products.

• Journal of Life Science
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• v.20 no.11
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• pp.1729-1737
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• 2010

This study was conducted to establish the optimal medium condition for the animal probiotic Lactobacillus plantarum by using onion juice. Cell yield and antioxidant activity increased in proportion to high additive levels of onion juice in medium. Onion juice, sucrose and yeast extract were selected as media ingredient factors and the effects of their mixed ratio in medium were evaluated. The full factorial design consisted of 24 experimental runs and was employed to estimate the main effects of the factors and their interactions. Significant positive effects on cell yield and antioxidant activity was shown with yeast extract and onion juice, respectively. Significant interaction was found only between sucrose and yeast extract in antioxidant activity. Finally, we selected an optimal medium that was composed of (g/l) onion juice, 600; sucrose, 15; yeast extract, 5. The efficiency of this optimum medium was estimated by using a 5 l jar fermenter. As a result, the maximum cell yield was $9.7\;{\log}_{10}$ (CFU/ml) at 12 hr. Cell yield at the end of incubation (20 hr) was $8.9\;{\log}_{10}$ (CFU/ml) and it was very similar with the predicted value, $9.0\;{\log}_{10}$ (CFU/ml). Antioxidant activity of culture was maintained at about 60~65% during all incubation time, resulting in a higher-than-predicted activity of 47.1%.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.3
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• pp.11-18
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• 2012

Increasing concern about biodiversity has lead to a rise in demand on the spatial assessment of biological resources such as biodiversity assessment, protected area selection, habitat management and restoration in Korea. The purpose of this study is to create species richness map through data collection and modeling techniques for wildlife habitat assessment. The GAM (Generalized Additive Model) is easy to interpret and shows better relationship between environmental variables and a response variable than an existing overlap analysis and GLM (Generalized Linear Model). The study area delineated by a large watershed contains Jirisan national park, Mt. Baekun and Sumjin river with three kinds of protected areas (a national park, a landscape ecology protected area and an otter protected area). We collected the presence-absence data for wildlife (mammals and birds) using a stratified random sampling based on a land cover in the study area and implemented natural and socio-environmental data affecting wildlife habitats. After doing a habitat use analysis and specifying significant factors for each species, we built habitat suitability models using a presence-absence model and created habitat suitability maps for each species. Biodiversity maps were generated by taxa and all species using habitat suitability maps. Significant factors affecting each species habitat were different according to their habitat selection. Although some species like a water deer or a great tit were distributed at the low elevation, most potential habitats for mammals and birds were found at the edge of a national park boundary or near a forest around the medium elevation of a mountain range. This study will be used for a basis on biodiversity assessment and proected area selection carried out by Ministry of Environment.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.4
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• pp.195-200
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• 2004

Ghrelin is a newly discovered peptide, which is released from the stomach and neurons in the hypothalamic arcuate nucleus (ARC), and potently stimulates growth hormone release and food intake. In the present study, we investigated the effect of ghrelin on $[Ca^{2+}]_i$ in thyroid FRTL-5 cells. Ghrelin (5 nM) increased $[Ca^{2+}]_i$ and TSH (1 unit/l) had an additive effect on $[Ca^{2+}]_i$ when extracellular normal solution was 1.1mM $Ca^{2+}$ containing Coon's modified Ham's F12 medium. When $Ca^{2+}-free$ medium containing 2 mM EGTA replaced the above normal solution, ghrelin also induced a similar rise in $[Ca^{2+}]_i$. In the middle of $[Ca^{2+}]_i$ increment by ghrelin, nifedipine $(1\;{\mu}M)$, nickel $(100\;{\mu}M)$ and $La^{3+}\;(100\;{\mu}M)$ had no effect on $[Ca^{2+}]_i$. After endoplasmic reticulum was depleted by cyclopiazonic acid $(CPA;10\;{\mu}M)$, ghrelin caused no visible change on $[Ca^{2+}]_i$ in $Ca^{2+}-free$/2 mM EGTA solution. These results suggest that ghrelin can increase $[Ca^{2+}]_i$ through endoplasmic reticulum in thyroid FRTL-5 cells.

• Geophysics and Geophysical Exploration
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• v.14 no.2
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• pp.140-145
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• 2011

In order to analyze the influence of the noise on a cross-well traveltime tomography to detect a small scale low velocity body in a homogeneous medium, the first arrival travel times were computed one a tunnel model by a finite-difference ray tracing scheme. Three different types and four different intensity levels of white noises were added to the computed first arrival travel times, and velocity tomograms were constructed using an iterative inversion method (SIRT). Tomograms with the noise intensity up to 10% of the maximum traveltime delay in the tunnel model, showed the exact location of the tunnel. However, the velocity shown at the tunnel location was not close to air velocity but only slightly less than the velocity of the background medium. The additive random noise showed significantly less degree of influence on the resulting tomogram than the source- and receiver consistent noise.

• Journal of Animal Science and Technology
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• v.51 no.6
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• pp.527-536
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• 2009

A potent protein degrading bacterium was isolated from soil samples of different environments. Polyphasic taxonomic studies and phylogenetic 16S rRNA sequence analyses led to identify the isolate IB No. 11 as a strain of Bacillus subtilis. The isolated strain was recognized to produce protease constitutively, and the maximum production (1.64 units/ml) was attained in a shake flask culture when the isolate was grown at $40^{\circ}C$, for 32 h in basal medium supplemented with starch (0.25%) and gelatin (1.25%) as sole carbon and nitrogen source, respectively. The optimum pH and temperature for the protease activity were determined to be pH 7.0 and $50^{\circ}C$, respectively. $Ca^{2+}$ and $Mn^{2+}$ enhanced remarkably the protease activity but neither showed positive effect on the protease's thermal stability. In addition, it was observed that the protease was fairly stable in the pH range of 6.5-8.0 and at temperatures below $50^{\circ}C$, and it could be a good candidate for an animal feed additive. The inhibition profile of the protease by various inhibitors indicated that the enzyme is a member of serine-proteases. A combination of UV irradiation and NTG mutagenesis allowed to develop a protease hyper-producing mutant strain coded as IB No. 11-4. This mutant strain produced approximately 3.23-fold higher protease activity (6.74 units/mg) than the parent strain IB No. 11 when grown at $40^{\circ}C$ for 32h in the production medium. The protease production profile of the selected mutants was also confirmed by the zymography analysis.