• Journal of Animal Science and Technology
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• v.52 no.1
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• pp.65-70
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• 2010

A bacterium producing acidic cellulase was isolated from pig feces. The isolate, ATC6 strain, was found to be Gram-positive, non-motile, catalase-positive, and spore-forming stain. Under an electron microscope, the cells were observed to be rod-shaped. The isolate was identified as Bacillus amyloliquefaciens ATC6 on the basis of morphological and biochemical properties as well as 16S rRNA gene sequences. Optimum pH and temperature for the cellulase activity of the culture supernatant of B. amyloliquefaciens ATC6 were found to be pH 4.5 and $55^{\circ}C$, respectively. More than 80% of its maximum activity was maintained at pH 4.0. The cellulase activity was maintained at temperatures ranging from 35 to $55^{\circ}C$ after 2 h incubation at pH 4.5, whereas it's activity decreased rapidly at $65^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.26 no.6
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• pp.476-482
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• 1998

Growth sensitivity of bifidobacteria on oxygen hindered their industrial applications so that it was necessary to select oxygen-tolerant strains. Studies on their responses to oxygen might facilitate the effective utilization of bifidobacteria in industry. Oxygen-tolerant strain of Bifidobacterium longum JI-1 was able to remove 3% dissolved oxygen within 10 min whilst oxygen-sensitive strain of B. adolescentis, slime non-former, was not. The ability to remove environmental oxygen seemed to be related to the oxygen-tolerance of bifidobacteria. Mutant B. longum ADJ-1 was induced from the B. longum JI-1 under microaerobic atmosphere. There were no differences in sugar utilization pattern, NADH oxidative enzymes and cellular fatty acid compositions between them. The maximal cell density of the mutant was a little bit reduced to 81% of that of the mother strain. However, the mutant formed thick slime layer around its cell. The layer visualized with confocal scanning laser microscopy from the mutant was 6 ${\mu}{\textrm}{m}$ in diameter but that from the mother strain was only 3 ${\mu}{\textrm}{m}$. Therefore, the improved tolerances of the mutant might come from the slime layer, indicating the increase of the layer might be one of oxygen tolerance mechanisms for bifidobacteria.

• Journal of Embryo Transfer
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• v.33 no.3
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• pp.129-137
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• 2018

Acute vascular rejection has been known as a main barrier occurring in a xenograted tissue of alpha 1,3-galactosyltransferase knock-out (GalT KO) pig into a non-human primate (NHP). Adenosine which is a final metabolite following sequential hydrolysis of nucleotide by ecto-nucleotidases such as CD39 and CD73, act as a regulator of coagulation, and inflammation. Thus xenotransplantation of CD39 and CD73 expressing pig under the GalT KO background could lead to enhanced survival of recipient NHP. We constructed a human CD39 and CD73 expression cassette designed for endothelial cell-specific expression using porcine Icam2 promoter (pIcam2-hCD39/hCD73). We performed isolation of endothelial cells (pAEC) from aorta of 4 week-old GalT KO and membrane cofactor protein expressing pig ($GalT^{-MCP/-MCP}$). We were able to verify that isolated cells were endothelial-like cells using immunofluorescence staining analysis with von Willebrand factor antibody, which is well known as an endothelial maker, and tubal formation assay. To find optimal condition for efficient transfection into pAEC, we performed transfection with GFP expression vector using four programs of nucleofection, M-003, U-023, W-023 and Y-022. We were able find that the program W-023 was optimal for pAEC with regard to viability and transfection efficiency by flow cytometry and fluorescent microscopy analyses. Finally, we were able to obtain $GalT^{-MCP/-MCP}/CD39/CD73$ pAEC expressing CD39 and CD73 at levels of 33.3% and 26.8%, respectively. We suggested that pACE isolated from $GalT^{-MCP/-MCP}$ pig might be provided as a basic resource to understand biochemical and molecular mechanisms of the rejections and as an alternative donor cells to generate $GalT^{-MCP/-MCP}/CD39/CD73$ pig expressing CD39 and CD73 at endothelial cells.

• Korean Journal of Poultry Science
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• v.10 no.2
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• pp.113-121
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• 1983

In an effort to understand epizootiological aspects of infectious laryngotracheitis (ILT), a total of 56 chicken flocks in six farms comprised of 35 broiler breeder, 13 commercial layer and 6 layer breeder flocks. were investigated. The farms experienced ILT during the period of one year from June, 1982. In most farms the birds were vaccinated against ILT just before or after the disease outbreak. In two of the farms in which ILT broke out in winter, it was possible to contain the disease in only one or two fleets without transmitting it to the remaining 5 to 7 flocks in the farms by adopting strict isolation procedures for the affected flocks. In regarding inter- flock spreading speed, it took an average of 6 days for flocks rearing on floor and 11 days for those in cages. Among the flecks in rearing cages. transmission among laying flocks was much faster. taking an average of 8 days, compared to non-laying flocks of 17 days, suggesting spreading of the disease by means of egg trays or egg collection process. Peak mortality was observed between 5 and 10 days after from the time of appearance of first dead birds from the disease and the period of mortality, with an average of 18 days, was not influenced by rearing systems, breeds and age of birds. Mortalities in the affected flocks ranged from lo/e to 19.8%, with an average of 6.5 %, and was also not influenced by the above variables except significantly lower mortality in immature broiler breeder flocks (2.9%) compared to immature layer (11.8%) and mature broiler breeder flocks (6.9%). In one breeder farm in which all the birds were kept on floor and ILT broke out in summer, mortality in male birds in all seven flocks of 37 weeks of age or older was as high as twice of that in female birds in the same flocks. This trend was not observed in one 31 weeks old flock and was reversed in another 14 weeks old flock in the farm.

• Journal of Wetlands Research
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• v.6 no.2
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• pp.65-71
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• 2004

The most significant effect of excess water in wetlands is the isolation of the soil from the atmosphere and the prevention of O2 from diffusing into soil. The blockage of atmospheric O2 induces biological and chemical processes that change soil from oxidized into reduced state. When dry soil develop into hydric soil, redox potential is dropping. The redox potential is a indicator of hydric soil and affect chemical function of wetlands. To reveal characteristics of wetland soil, redox potential was measured in Jinkwannaedong ecological conservation area from May in 2003 to March in 2004. Redox potentials in May ranged from 5 mV at 25 cm depth to 200 mV at 10 cm depth. It decreased to about -200 m V at all depths and continued until October. In winter, redox potential was slowly increased; it was the highest at 5 cm depth and lowest at 20 cm depth. Annual variations of redox potential in 20 cm depth showed the same pattern at 5 sites; low in growing season and high in non-growing season. This results indicates that soils of study sites are in hydric state and methanogenesis is occurring in Jinkwannaedong ecological conservation area.

• The Korean Journal of Mycology
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• v.13 no.4
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• pp.203-212
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• 1985

Of 450 strains isolated from the soil microbes collected in various locations in Korea, a strain had a strong inhibitory activity against bacterial ${\alpha}-amylase$ and was named strain DMC-72 of the genus Streptomyces. The amylase inhibitory metabolite produced by this strain was purified by means of acetone precipitation, adsorption on Amberlite IRC-50 and SP-Sephadex C-25. The inhibitor was found to be a derivative of oligosaccharides by spectral and chemical data. The inhibitor was stable at the pH range of $1{\sim}13$ and at $100^{\circ}C$ for half an hour, also inhibited other amylases such as salivary ${\alpha}-amylase$, pancreatic ${\alpha}-amylase$, fungal ${\alpha}-amylase$ and glucoamylase. However, it showed no inhibitory activity against ${\alpha}-glucosidase$, ${\beta}-glucosidase$, dextranase, and ${\beta}-amylase$. The kinetic studies of the inhibitor showed that its inhibitory effects on starch hydrolysis by ${\alpha}-amylase$ were noncompetitive.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.4
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• pp.863-872
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• 2015

Kernel rootkit is recognized as one of the most severe and widespread threats to corrupt the integrity of an operating system. Without an external monitor as a root of trust, it is not easy to detect kernel rootkits which can intercept and modify communications at the interfaces between operating system components. To provide such a monitor isolated from an operating system that can be compromised, most existing solutions are based on external hardware. Unlike those solutions, we develop a kernel introspection system based on the ARM TrustZone technology without incurring extra hardware cost, which can provide a secure memory space in isolation from the rest of the system. We particularly use a secure timer to implement an autonomous switch between secure and non-secure modes. To ensure integrity of reference, this system measured reference from vmlinux which is a kernel original image. In addition, the flexibility of monitoring block size can be configured for efficient kernel introspection system. The experimental results show that a secure kernel introspection system is provided without incurring any significant performance penalty (maximum 6% decrease in execution time compared with the normal operating system).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.1
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• pp.49-62
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• 2011

Recently, International Atomic Energy Agency and major leading countries in radioactive waste management tend to subdivide the categories of radioactive waste based upon risk-graded approach. In this context, the category of very low level waste has been newly introduced, or optimized management options for this kind of waste have been pursued in many countries. The application of engineered surface landfill type facilities dedicated to dispose of very low level waste has been gradually expanded, and it was analyzed that their design concept of isolation has been much advanced than those of the old fashioned surface trench-type disposal facilities for low and intermediate level waste, which were usually constructed in 1960's. In addition, the management options for very low level waste in major leading countries are varied depending upon and interfaced with the affecting factors such as: national framework for clearance, legal and practical availability of low and intermediate level waste repository and/or non-nuclear waste landfill, public acceptance toward alternative waste management options, and so forth. In this regard, it was concluded that optimized long-term management options for very low level waste in Korea should be also established in a timely manner through comprehensive review and discussions, in preparation of decommissioning of large nuclear facilities in the future, and be implemented in a systematic manner under the framework of national policy and management plan for radioactive waste management.

• Korean Journal of Environmental Agriculture
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• v.11 no.1
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• pp.77-85
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• 1992

Of the cadmium-tolerant 162 bacterial strains isolated from soils, river waters or active sludges of waste-water disposal plants in the Gyeongnam province a strain C1, which showed considerably higher growth rate in the agar plate containing 2000 ppm than any other strains isolated, was identified as a Pseudomonas putida or its similar strain when analyzed by taxonomical characteristics. Optimum pH and temperature for the growth of the P, putida were 7.0 and $30^{\circ}C$, respectively. This strain was resistant to antibiotics(ampicillin, chloramphenicol and streptomycin), and heavy metals(lithium, cupper, lead and zinc). This strain utilized salicylate, naphthalene or xylene as a sole carbon source. The rate of cadmium accumulation in P. putida cell was enhanced at low concentration of Cd in the growth media. The maximum cadmium absorption by this strain grown in 1 and l0ppm of Cd was respectively 78% and 60% 24 hrs after culture, but in 100 ppm Cd, 40% 48 hrs after culture. Addition of a non-ionic surfactant Triton X-100(0.1%) to the medium enhanced the accumulation of cadmium in the P. putida up to approximately 37%.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.3 s.58
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• pp.149-152
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• 2006

Natural safflower oleosomes are small ($1{\sim}3{\mu}m$) spherical shaped "reservoir", inside which the seed stores triglycerides for use as a future energy source. The surface of the oleosome is covered with a high molecular weight ($20{\sim}24$ KDa) oleosin protein which has been demonstrated to have emulsification properties. Traditionally, oleosomes from oil bearing seeds such as safflower were simply crushed to liberate the oil within. Our patented DermaSphere technology allows for the isolation of oleosomes in the intact state. Once isolated, these materials can be used in skin care formulations to deliver the emolliency, occlusivity, and anti-oxidant effects typically associated with safflower oil. However, because of the presence of the emulsifying oleosin protein covering the spherical oil body, oleosomes have self-emulsification property as well as can emulsify other oil phase in typical oil-in-water (O/W) emulsion. The oleosomes can literally serve as the entire non-active portion of the oil phase of a typical skin care product. Most importantly, natural oleosomes can be loaded with other oil-soluble active materials and can therefore be used as delivery systems for improved cosmetic efficacies. Oleosomes can be loaded with various actives, such as fragrances, vitamins, inset repellents, and UV chromophores. The loaded oleosomes can be utilized to either protect the active ingredients within the formulation itself or to allow for control release of those actives over time.