• Restorative Dentistry and Endodontics
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• v.29 no.3
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• pp.205-211
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• 2004

This study evaluated the microleakage and interfacial gap between enamel and composite resin under the dry and wet condition of the enamel surface. V shaped class 5 cavities were prepared on the occlusal portion of extracted human molars. Samples were divided into three groups：D group (air dry for 10-15s), BD group (blot dry with moist cotton pellet), and DR group (air dry for 10-15s and rewet with Aqua-Prep F for 20s), Cavities were filled using Aelitefil composite resin after applied One-Step. Microleakage was tested by 2% methylene blue dye solution and the data were statistically analysed by Kruskal-Wallis test and Mann-Whitney test. Also Enamel-resin interface was observed under SEM. Group BD showed statistically lower microleakage than group D (p < 0.05). but there was no statistically significant difference between group BD and DR (p > 0.05). At the enamel-resin interface, group D showed the gap of $2{\;}{\mu}m$ thickness, but group BD and DR showed close adaptation. In conclusion, the use of blot dry and rewetting agent (Aqua-Prep F) resulted in decreased microleakage and improved adhesion between enamel and resin when using One-Step.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.16 no.1
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• pp.94-99
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• 2003

Objectives : Gram-positive bacteria have became increasing resistant to antibacterial agents, and hence multi-drug-resistant bacterial pathogens are now a major problem in clinical medicine. There is, therefore, a need for new antibacterial agents. In the course of our screening program for potent antibacterial agent from medicinal plants, the extract of Salvia miltiorrhiza (S. miltiorrhiza) showed antibacterial activity against methcillin resistant Staphylococcus aureus (MRSA) and antibiotic-resistant S. aureus. Methods : S. miltiorrhiza was extracted with 80$\%$ EtOH. The extract was suspended in H2O and fractionated successively with hexane chloroform, ethyl acetate, and n-buthanol. The chloroform fraction, which showed the highest antibacterial activity(MICs, 78㎍/ml) against MRSA, was chromatographed on a silica gel column and recycling prep-LC to give the pure antibacterial component. Results and Conclusions : The second fraction among the chloroform soluble portion of an aqueous EtOH extract of S. miltiorrhiza root showed outstanding antibacterial activity against MRSA and antibiotic-resistant S. aureus compared to the other fraction. An active compound was isolated from the second fraction using silica gel column chromatoraphy and recycling prep-LC. Based on these data together with the IH-, 13C-NMR, mass and mp, the active compounds were identified tanshinone Ⅰ, dehydrotanshinone Ⅰ and cryptotanshinone. Among tanshinones, cryptotanshinone and dihydrotanshinone Ⅰ MICs against MRSA and antibiotics-resistant S. aureus were 12.5, 12.5 and 6.3㎍/ml, respectively.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.311-320
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• 2021

At present, the secondary school teacher employment examination(SSTEE) is the only gateway to become a national and public secondary teacher in Korea, and after the revision from the 2014 academic year, all the questions of the exam have been converted to supply-type test items, requiring more definitive, accurate, and solid answers. Compared to the selection-type test items that measure recognition memory, the supply-type questions, testing recall memory, require constant memorization and retrieval practices to furnish answers; however, there is not enough learning tools available to support the practices. At this juncture, this study invented a mobile app, called ONE PASS, for the SSTEE. By unpacking the functional mechanisms of the brain, the basis of cognitive processing, this ONE PASS app offers a set of tools that feature brain-based learning principles, such as a personalized study planner, motivation measurement scales, mind mapping, brainstorming, and sample questions from previous tests. This study is expected to contribute to the research on the development of learning contents for applications, and at the same time, it hopes to be of some help for candidates in their exam preparation process.

• Journal of Convergence for Information Technology
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• v.11 no.6
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• pp.107-112
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• 2021

This study aims to analyze a cafe built by reflecting the characteristics of Jeju among the cafes in Jeju. This is to provide practical help to prospective prep entrepreneurs who want to start a cafe in Jeju. The cafe reflecting the characteristics of Jeju maintains its own competitiveness and constant interest of tourists by securing differentiation and uniqueness. In addition, by looking at the characteristics of Jeju applied to cafe architecture, the academic foundation for understanding the Jeju and applicable characteristics of Jeju were summarized. The study was conducted in parallel with literature analysis and on-site analysis, and as a result, the following contents were found. First, it is a reflection of Jeju's phenomenal materiality. Second, it is a reflection of Jeju's interpretive everyday life. Third, it is a reflection of Jeju's materiality time. In this regard, if prep entrepreneurs start a cafe that reflects the characteristics of Jeju, they can create a cafe with very specific characteristics if they integrate the three characteristics above.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.214-219
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• 2012

This study aimed to develop a new type of functional citrus beverage (Citurs-F) containing flavonoids extracted from the young fruits of satsuma mandarin ($Citrus$ $unshiu$) and matured fruits of Jeju native dangyooja ($C.$ $grandis$). We made beverages that contained 30% of satsuma mandarin extract with different percentages of concentrated dangyooja-derived flavonoid extracts. In sensory evalution, the highest response indices of color, taste and aroma were from the beverages based on the 30% young fruit extracts plus 15% (Citrus-F-15) and 20% (Citrus-F-20) flavonoids extract from the dangyooja using the KILO prep. In the changes of body weight after oral administration of the Citrus-F, the rat group with HF diet plus the Citrus-F decreased the body weight compared to the rat group fed only HF diet. This effect was to be continued for 9 weeks until the end of experiment. In the lipid content in blood, the rat group with oral administration of citrus extractions merely tended to resolve it in serum test. However, all the 0.1% Citrus-F-15 and Citrus-F-20 treated rat groups from the beginning or after 5 weeks appeared the lowest lipid contents in the blood. In the cholesterol contents, the rat group feeding the KILO-prep's extraction from the beginning weren't significantly recognized them in the group but the rat group feeding 0.1% Citrus-F-15 acted to reduce in the cholesterol contents from 5 weeks. The results indicated that the Citrus-F-15 with rich flavonoids might be main source alleviating the vascular diseases and obesity in human diet.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.2
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• pp.100-106
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• 2004

Micro-fluidics is one of the major technologies used in developing micro-total analytical systems (${\mu}$-TAS), also known as “lab-on-a-chip”. With this technology, the analytical capabilities of room-size laboratories can be put on one small chip. In this paper, we will briefly introduce materials that can be used in micro-fluidic systems and a few modules (mixer, chamber, and sample prep. modules) for lab-on-a-chip to analyze biological samples. This is because a variety of fields have to be combined with micro-fluidic technologies in order to realize lab-on-a-chip.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.438-441
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• 2008

A novel lactobacilli replicon from plasmids of Lactobacillus reuteri KCTC 3678 was isolated. Eight L. reuteri strains from Korean Collection for Type Cultures (KCTC) and Korea Food Research Institute (KFRI) were screened for cryptic plasmids and most strains harbored 1 or 2 plasm ids. Particularly, L. reuteri KCTC 3678 contained 6 plasm ids which all were used for screening of lactobacilli replicon. EcoRI digests of the plasmid DNA prep from L. reuteri KCTC 3678 were ligated with pUC19 and the recombinant DNAs were serially named from pLR1 to pLR7. A cat (chloramphenicol acetyltransferase; $Cm^r$) gene originated from pC194 was introduced into pLR1-7, resulting in pLR1cat-pLR7cat, respectively. The recombinant plasmids were introduced into L. reuteri KCTC 3679, and only transformants harboring pLR5cat were obtained, indicating that the insert in pLR5 functioned as a lactobacilli replicon.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.134.2-135
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• 2003

The plant-pathogenic species S. scabies, S. acidiscabies, and S. turgidiscabies cause the scab disease of potato and produce the phytotoxins, thaxtomins. necl, a gene conferring a necrogenic phenotype, is involved in pathogenicity and physically linked to the thaxtomin A biosynthetic genes. Identification of the pathogenic strains of Streptomyces from soil was performed through the polymerase chain reaction by using specific pathogenicity primer sets derived from the necl gene sequences of Streptomyces smbies. The DNA was extracted from soil using a bead-beating machine and modifications of the FastPrep system. The DNA was suitable for direct use in the PCR. The PCR products showed the bands of approximately 460 bp. This methods can be very usuful in identifying species responsible for scab diseases and studying on the ecology of plant-pathogenic Streptomyces spp.

• Natural Product Sciences
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• v.15 no.4
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• pp.181-184
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• 2009

Phytochemical constituents were isolated from the seeds of Lithospermum erythrorhizon through open column chromatography and prep-HPLC. Their structures were identified as ${\beta}$-sitosterol (1), daucosterol (2), luteolin (3), and allantoin (4) on the basis of spectroscopic analysis. Among them, luteolin (3) was isolated for the first time from the plant.

• Archives of Pharmacal Research
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• v.5 no.1
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• pp.7-12
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• 1982

Ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf and Rg1 were effectively isolated from ginseng root by preparative liquid chromatography (LC) on two PrepPAK-500/c18 cartridges in series and semipreparative LC on a .mu. Bondapak cabohydrate analysis column, a .mu.Bondapak C18 column or a .mu. Porasil column. The identities of the isolated ginsenosides were confirmed by analytical high-performance liquid chromatography (HPLC) and infrared spectrophotometry. By this method large scale isolation of pure ginsenosides was efficiently accomplished.