• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.385-389
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• 2012

The application of microorganisms in the field of construction material is rapidly increasing worldwide; however, almost all studies that were investigated were bacterial sources with mineral-producing activity and not with organic substances. The difference in the efficiency of using bacteria as an organic agent is that it could improve the durability of cement material. This study aimed to assess the use of biofilm-forming microorganisms as binding agents to increase the compressive strength of cement-sand material. We isolated 13 alkaliphilic biofilmforming bacteria (ABB) from a cement tetrapod block in the West Sea, Korea. Using 16S RNA sequence analysis, the ABB were partially identified as Bacillus algicola KNUC501 and Exiguobacterium marinum KNUC513. KNUC513 was selected for further study following analysis of pH and biofilm formation. Cement-sand mortar cubes containing KNUC513 exhibited greater compressive strength than mineral-forming bacteria (Sporosarcina pasteurii and Arthrobacter crystallopoietes KNUC403). To determine the biofilm effect, Dnase I was used to suppress the biofilm formation of KNUC513. Field emission scanning electron microscopy image revealed the direct involvement of organic-inorganic substance in cement-sand mortar.

• Journal of Microbiology and Biotechnology
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• v.20 no.12
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• pp.1672-1676
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• 2010

The Actinomycete strain KH29 is antagonistic to the multidrug-resistant Acinetobacter baumannii. Based on the diaminopimelic acid (DAP) type, and the morphological and physiological characteristics observed through the use of scanning electron microscopy (SEM), KH29 was confirmed as belonging to the genus Streptomyces. By way of its noted 16S rDNA nucleotide sequences, KH29 was found to have a relationship with Streptomyces cinnamonensis. The production of an antibiotic from this strain was found to be most favorable when cultured with glucose, polypeptone, and yeast extract (PY) medium for 6 days at $27^{\circ}C$. The antibiotic produced was identified, through comparisons with reported spectral data including MS and NMR as a cyclo(L-tryptophanyl-L-tryptophanyl). Cyclo(L-Trp-L-Trp), from the PY cultures of KH29, was seen to be highly effective against 41 of 49 multidrug-resistant Acinetobacter baumannii. Furthermore, cyclo(L-Trp-L-Trp) had antimicrobial activity against Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, Saccharomyces cerevisiae, Aspergillus niger, and Candida albicans, However, it was ineffective against Streptomyces murinus.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.312-315
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• 2014

So as to evaluate its use an immune stimulator in humans, the toxicity and action against immune cells by an anti-yeast substance (AYS), a bacterial proteoglycan, were investigated. The AYS did not possess hemolytic activity with human red blood cells (hRBC). Nor did it exhibit cytotoxicity against human peripheral blood mononuclear cells (hPBMC). In addition, the AYS did not induce hPBMC proliferation, but it did agglutinate hPBMCs in vitro. Moreover, hPBMC induced inflammatory cytokines such as IL-6, IL-5, IFN-${\gamma}$ and TNF-${\alpha}$ with the AYS during culture. Compared with alum, the AYS as an adjuvant has an increased antibody production rate against bovine serum albumin (BSA) in mice.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.490-493
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• 2002

Many servers that is operated in present earth are UNIX base, is trend that server of LINUX base is increasing steadily recently. When users who have account to this server wish to do remote access, instruction that use most easily is‘telnet’, security does not consist entirely about ID and password that this uses at communication substance as well as login. The interest about latest SSH is rising by the alternative, but SSH has various kinds problem in following telnet's fame. Therefore, We studied about problems and the solution that can happen when window users attempted remote access laying stress on OpenSSH.

• Nuclear Engineering and Technology
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• v.2 no.2
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• pp.73-84
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• 1970

The metabolism of sterol precurosor in leaves of Salanum andigena grafted between photoinduced and noninduced plant was investigated with the use of (2-$^{14}$ C) mevalonic acid. By the technique of the preparative gas-liquid chromatography, radioactive compounds of squalene, 4,4’-dimethylsterols and 4-demethylsterol were isolated and determined quantitatively. When labeled mevalonic acid n as applied to leaves radioactivity was extensively incorporated into non-saponifiable materials of lipid fraction and aqueous fraction (ethanol-water fraction). Radioactivity of 14C derived from (2-$^{14}$ C) mevalonic acid was transmissible from photoinduced plant to non-induced plant across the graft union, as tuberization hormone was, and incorporated into the sterols of the non-induced plant. Inhibitors of sterol biosynthesis, SK & F 7997 and nicotinic acid, are effective suppressors of tuber growing, if applied to leaves during photoinduction period. The experimental results suggest that certain substance containing isoprene unit, or sterol-like compound may participate in tuber growing.

• Research in Community and Public Health Nursing
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• v.16 no.1
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• pp.40-48
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• 2005

Purpose: This study was performed to identify the relationship between stress perceived by middle school students and social support level and to investigate the factors affecting middle school students' smoking behavior. Method: The data was collected from four hundred and thirteen students of one boys' middle school and one girls' middle school. Data were analyzed by using SPSS 11.5 Win Program. Result: Smoking rate was higher in girls than boys. The factors affecting smoking behavior were drinking (OR=67.62, P<0.01), having one parent or no parents(OR=9.98, P<0.05), and higher material support(OR=4.67, P<0.05). Conclusion: This results showed that smoking prevention program is needed for girls' middle school students. To prevent smoking, teachers should help students to cope with stress from schools and their environments with careful guidance, and organized support for the student with one parent or no parents should also be established. Furthermore, guidance in student's relationships with peers is needed regarding appropriate allowance, drinking, or substance use.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.113-117
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• 2009

Fly ash (called FA hereafter) that results from thermal power plants is a long-term strength improving substance with reactivity to pozzolan and has been used for long. However, large amount of FA shows many advantages such as reduction of hydratio energy, long-term improvement in strength and economic feasibility and also has difficulties from reduction in initial strength and durability. In a preceding study, fine particle cement was applied to test the effects on initial strength. Therefore in this study, the effects of fine particle cement on the quality of FA concrete were reviewed. The results can be summarized as follows. Liquidity was increased by the most at FC substitution ratio of 15%. Air capacity was reduced according to increasing substitution ratio of FA and FC. Compressive strength showed high strength expression at all ages when FC was substituted at 45%. Synthesizing the above results, appropriate mixing of FC in FA concrete can improve liquidity, reduce unit quantity and show improvement in strength. In particular, mixed use of FC seems effective in improving early quality of concrete.

• The Journal of the Korean dental association
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• v.52 no.8
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• pp.456-463
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• 2014

Caries Management by Risk Assessment (CAMBRA), published by California Dental Association in 2003, is a customized caries care system that classifies individuals' caries risk into 4 risk groups based on objective evidences and provides chemical treatments targeted for each caries risk level. However, this system was not only developed but also optimized for situation in the United States, resulting into many limitations to be used in Korea, and thus Korean CAMBRA (K-CAMBRA) that considers the clinical situation in Korea needs to be developed. K-CAMBRA includes various techniques that are newly developed in order to overcome the limitations. First, Q-ray, a new optical technology, is utilized in order to avoid the subjectivity of visual inspection during assessment of disease indicators and risk factors. Moreover, Cariview? that reflects the paradigm shift in cariology as a new form of caries assessment kit is used. In addition, considering the situation in Korea, where it is impossible to use high concentration fluoride product, Oral pack with a customized tray is added to increase the contact time of chemical substance. CAMBRA is believed to be the key clinical tool that overcomes the limitations of the paradigm of the conventional restoration-based surgical model of dentistry. Furthermore, it can be expected that Korean dentists can act as oral physicians who are able to control and care individuals' caries risk rather than operative experts who only care about the outcome of caries.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.12a
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• pp.91-95
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• 2006

In whole world consciousness of environment maintenance have increased very quickly for the end of the 20th century. To use and disuse toxic substances have been controled at the field of industry. Also the field of lighting source belong to environmental control. And in the future the control will be strong. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem root. In the mercury free lighting source system the Xe gas lamp is one type. And the Ne:Xe mixing gas lamp improvements firing voltage of Xe gas lamp. Purpose and subject of this study are understand, efficiency, ideal of Ne:Xe plasma which mercury free lamp. Before ICP was designed, basic parameters of plasma, which are electron temperature and electron density, were measured and calculated by langmuir probe data. Property of electron temperature and electron density were confirmed by changing ratio of Ne:Xe.

• Journal of Korean Society for Quality Management
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• v.12 no.1
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• pp.35-44
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• 1984

Spandex is a elastomeric fiber in which the-fiber-forming substance is a long chain polymer consisting of at least 85% segmented polyurethane. In the polyurethanes there are the additional oxygen atoms in the main chains of the molecule. The effect of these oxygen atoms is to make the molecule flexible. From a physical point of view, elasicity and recovery from stretch are the most important properties of polyurethane, so its use had now expanded into many knitting industry. In this paper, we wish to Test the effect of some finishing conditions on the quality of polyurethane.