• The Journal of the Korea Contents Association
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• v.21 no.6
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• pp.639-652
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• 2021

In accordance with the rapidly changing social environment, it is becoming more important to cultivate creative and convergent practical talents with flexible thinking skills and problem-solving skills. Therefore, it is necessary for universities to provide educational experiences that enable students to cooperate and converge multidisciplinaryly to carry out on-the-job projects based on what they have learned at school. Therefore, this study designed, developed, and operated with the aim of cultivating creative talents with integrated problem-solving ability through a multidisciplinary capstone design curriculum based on industry-academia cooperation. To this end, the curriculum was developed together by recruiting participating companies and forming a convergence professor team, and it was operated for 15 weeks for students majoring in cosmetics engineering at D University. After the education was over, learning satisfaction and perceived academic achievement were surveyed, and as a result of the analysis, it was found to be above average with 3.77 points and 3.86 points, respectively. And as a result of the in-depth interview on the participation experience, five themes related to the positive experience and three themes related to the negative experience were derived. This study will be able to provide basic data when operating a multidisciplinary convergence capstone design curriculum based on industry-academia cooperation in the future.

• Journal of Life Science
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• v.22 no.5
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• pp.605-612
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• 2012

Spore-forming bacteria are being used as probiotic supplements for human and animal use, due to their low pH stability and ability to survive the gastric barrier. In this study, the BCNU 9028 strain was screened from meju, a Korean fermented soybean food starter. Biochemical and physiological characteristics, as well as 16S rDNA sequence analyses, indicate that this strain belongs to the genus $Bacillus$. $Bacillus$ sp. BCNU 9028 showed a 92% survivability at pH 2.5 and could also withstand 0.3% ox bile. Furthermore, it was postulated that $Bacillus$ sp. BCNU 9028 could prevent biofilm formation and adherence of food-borne pathogens such as $Listeria$ $monocytogenes$, $S.$ $aureus$ and $E.$ $coli$ on the basis of its autoaggregation and coaggregation capacity with food-borne pathogens. It was shown that BCNU 9028 has good abilities to adhere to the intestinal tract from its hydrophobic character (63.3%). The $Bacillus$ sp. BCNU 9028 strain especially elicited antibacterial activity against both Gram-positive and -negative pathogens. These findings suggested that the $Bacillus$ sp. BCNU 9028 strain could be used as a potential probiotic.

• Applied Chemistry for Engineering
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• v.25 no.6
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• pp.570-576
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• 2014

Palmitoyl tripeptide (M330) showed higher antimicrobial activities than methyl paraben or phenoxy ethanol through minimum inhibitory concentration (MIC) test. However, when the M330 was added into cosmetic formulation, white precipitates formed due to the electrostatic interaction between M330 and carbopol (carboxy vinyl polymer) as a thickener in cosmetics, and the viscosity of cosmetics decreased sharply. Also, the antimicrobial activities of M330 in cosmetics became lower than those of methyl paraben or phenoxy ethanol. Thus, the encapsulation of M330 in ethosome vesicle was attempted in order to recover the declined antimicrobial activities of M330 in cosmetics and prevent the precipitates from forming. When ethosome-encapsulated M330 was added into cosmetics, the precipitates did not form, and the decrease in the viscosity of cosmetics was not large compared to the addition of unencapsulated M330. Challenge tests showed that antimicrobial activities against gram negative bacteria were improved by the encapsulation of M330, but the encapsulation was not effective against gram positive bacteria and fungus. A combination of M330 with EDTA showed synergistic inhibitory potential against C. albicans. After coencapsulation of M330 and EDTA in ethosome, antimicrobial activities proved to be higher than those of unencapsulated M330 and EDTA.

• Applied Biological Chemistry
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• v.11
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• pp.137-141
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• 1969

In order to obtain amino acids and nucleic acid derivatives from adenine auxotrophic mutants of Bacillus subtilis and Escherichia coli, vitamin, nucleic acid analogue, streptomycin as well as ultraviolet light were adopted for the production of adenine auxotrophic mutants and the results showed efficient production of desired mutants. 1. Ultraviolet ray $(2530\;{\AA}\;2080\;erg/mm^2)$ irradiation to Bacillus subtilis and E. coli at a distance of 30 cm for 80-90 sec. and for 15-20 sec. respetively induced four and eight strains of auxotrophic mutants. 2. Treatment of aminopterine$(200\;{\mu}g/ml)$ inhibited the growth of Bacillus sultilis significantly but a subsequent irradiation of ultraviolet light at the above mentioned conditions induced six times as much mutants as compared to the irradiation alone. In case of E. coli a similar tendency was observed with treatment of streptomycin$(200\;{\mu}g/ml)$ with doubled induction rate of adenine auxotrophic mutants as compared to the irradiation alone.

• Korean Journal of Food Science and Technology
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• v.53 no.2
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• pp.218-222
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• 2021

This study aimed to investigate bacterial disinfection in drinking water using a water purifier. Water artificially inoculated with Escherichia coli and Listeria monocytogenes at various concentrations was irradiated using ultraviolet (UV)-C at a rate of 3.4 L/min in a water purifier, and the disinfection effects of UV-C were evaluated. Both E. coli and L. monocytogenes were disinfected up to 107 colony-forming units (CFU)/2.8 L by the UV-C irradiation. Additionally, morphological study using fluorescence microscopy in conjunction with live/dead staining revealed that both the bacteria species were disinfected by the UV-C irradiation. Therefore, UV-C in water purifiers can effectively kill high concentrations of bacteria in distilled water. UV irradiation (UV-C: 254 nm wavelength, irradiation dose: 40 mJ/㎠) at a flow rate of 3.4 L/min on drinking water has the potential to sterilize bacteria-contaminated drinking water, at least for 3.2×107 CFU/2.8 L of E. coli and 8.4×107 CFU/2.8 L of L. monocytogenes.

• Informatization Policy
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• v.24 no.1
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• pp.3-29
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• 2017

The purpose of this research is to understand immersive media such as virtual reality, augmented reality, mixed reality, 360-degree videos etc. from the perspective of user-based approach. 3D videos were once expected as the next-generation industry, but soon it further evolved into UHD and are now followed by immersive media represented by virtual reality. As the virtual reality plays an important role, the current research tries to bring up implications that can be applied to the industrial field along with academic understanding through six theoretical approaches related to virtual reality such as media richness, interactivity, presence, body-ownership, user experience, and visual perception. These six theories were used in immersive media studies such as 3D videos. Media richness and interactivity are the main factors forming positive or negative attitude, presence explains why users are immersed, user experience accounts for total psychological reaction, and visual perception explains how complex the experience of seeing is. Especially, although there is less media research applied, the body-ownership is likely to be not only used in virtual reality research, but immersive media research. The user-based theories related to virtual reality will provide various implications for immersive media researchers as well as hardware and content creators of virtual reality.

• Journal of Life Science
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• v.16 no.1
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• pp.37-43
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• 2006

Gap junction is an ion channel forming between adjacent cells. It also acts as a membrane channel like sodium or potassium channels in a single cell. The amino acid residues up to the $10^{th}$ position in the amino (N)-terminus of gap junction hemichannel affect gating polarity as well as current-voltage (I-V) relation. While wild-type Cx32 channel shows negative gating polarity and inwardly rectifying I-V relation, T8D channel in which threonine residue at $8^{th}$ position is replaced with negatively charged aspartate residue shows reverse gating polarity and linear I-V relation. It is still unclear whether these changes are resulted from the charge effect or the conformational change of the N-terminus. To clarify this issue, we made a mutant channel harboring cysteine residue at the $8^{th}$ position (T8C) and characterized its biophysical properties using substituted-cysteine accessibility method (SCAM). T8C channel shows negative gating polarity and inwardly rectifying I-V relation as wild-type channel does. This result indicates that the substitution of cysteine residue dose not perturb the original conformation of wild-type channel. To elucidate the charge effect two types of methaenthiosulfonate (MTS) reagents (negatively charged $MTSES^-$ and positively charged $MTSET^+$) were used. When $MTSES^-$ was applied, T8C channel behaved as T8D channel, showing positive gating polarity and linear I-V relation. This result indicates that the addition of a negative charge changes the biophysical properties of T8C channel. However, positively charged $MTSET^+$ maintained the main features of T8C channel as expected. It is likely that the addition of a charge by small MTS reagents does not distort the conformation of the N-terminus. Therefore, the opposite effects of $MTSES^-$ and $MTSETT^+$ on T8C channel suggest that the addition of a charge itself rather than the conformational change of the N-terminus changes gating polarity and I-V relation. Furthermore, the accessibility of MTS reagents to amino acid residues at the $8^{th}$ position supports the idea that the N-terminus of gap junction channel forms or lies in the aqueous pore.

• The Journal of the Korean bone and joint tumor society
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• v.5 no.3
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• pp.162-168
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• 1999

The products of c-fos and c-jun proto-oncogenes form the heterodimeric complex activator protein 1 (AP-1), which plays an important part in the control of bone cell proliferation and differentiation, as well as in the development of bone tumors. The expression of c-fos protein was examined in 35 cases of human osteosarcomas as formalin-fixed paraffin-embedded tissue sections using a monoclonal antibody. The expression of c-fos was restricted to bone-forming lesions, while low grade cartilaginous tumors were devoid of immunoreactivity. The highest levels of c-fos expression were detected in osteoblastic osteosarcoma (13 of 17 cases with grade one on two) while two chondroblastic osteosarcomas, one fibroblastic osteosarcoma, and two parosteal osteosarcomas were negative. Two cases of telangiectatic osteosarcomas were positive for c-fos protein. However, since there is a tendency of high c-fos protein expression at the higher histological grade, significant differences were not present in the expression of c-fos protein. Thus c-fos expression may be implicated in the development of osteosarcomas, but they appear to have little or no relevance in the development of low grade cartilaginous neoplasms.

• Communications of Mathematical Education
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• v.25 no.2
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• pp.403-430
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• 2011

The purpose of the study was to investigate how the use of graphing calculators influence on forming students' mathematical concept of algebra, students' mathematical connection, and attitude toward mathematics. First, graphing calculators give instant feedback to students as they make students compare their written answers with the results, which helps students learn equations and linear inequalities for themselves. In respect of quadratic inequalities they help students to correct wrong concepts and understand fundamental concepts, and with regard to functions students can draw graphs more easily using graphing calculators, which means that the difficulty of drawing graphs can not be hindrance to student's learning functions. Moreover students could understand functions intuitively by using graphing calculators and explored math problems volunteerly. As a result, students were able to perceive faster the concepts of functions that they considered difficult and remain the concepts in their mind for a long time. Second, most of students could not think of connection among equations, equalities and functions. However, they could understand the connection among equations, equalities and functions more easily. Additionally students could focus on changing the real life into the algebraic expression by modeling without the fear of calculating, which made students relieve the burden of calculating and realize the usefulness of mathematics through the experience of solving the real-life problems. Third, we identified the change of six students' attitude through preliminary and an ex post facto attitude test. Five of six students came to have positive attitude toward mathematics, but only one student came to have negative attitude. However, all of the students showed positive attitude toward using graphing calculators in math class. That's because they could have more interest in mathematics by the strengthened and visualization of graphing calculators which helped them understand difficult algebraic concepts, which gave them a sense of achievement. Also, students could relieve the burden of calculating and have confidence. In a conclusion, using graphing calculators in algebra and function class has many advantages : formulating mathematics concepts, mathematical connection, and enhancing positive attitude toward mathematics. Therefore we need more research of the effect of using calculators, practical classroom materials, instruction models and assessment tools for graphing calculators. Lastly We need to make the classroom environment more adequate for using graphing calculators in math classes.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.1-26
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• 1996

This study was performed to estimate the effects of cultured bone cell inoculated on porous type hydroxyaptite for the regeneration of the artificial alveolar bone defect. In this experiment 3 beagle dogs were used, and each of them were divided into right and left mandible. Every surgical intervention were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium(30mg/Kg). To reduce the gingival bleeding during surgery, operative site was injected with Lidocaine hydrochloride(l:80,000 Epinephrine) as local anesthesia. After surgery experimental animal were feeded with soft dietl Mighty dog, Frisies Co., U.S.A.) for 1 weeks to avoid irritaion to soft tissue by food. 2 months before surgery both side of mandibular 1st premolar were extracted and bone chips from mandibular body were obtained from all animals. Bone cells were cultured from bone chips obtained from mandible with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Porous type hydroxyapatite were immerse into the high concentrated cell suspension solution, and put 4 hours for attachin the cells on the surface of hydroxyapatite. Graft material were inserted on the artificial bone defect after 3 days of culture. Before insertion of cellinoculated graft material, scanning electronic microscopic observation were performed to confirm the attachment and spreading of cell on the hydroxyapatite surface. 3 artificial bone defects were made with bone trephine drill on the both side of mandible of the experimental animal. First defect was designed without insertion of graft material as negative control, second was filled with porous replamineform hydroxyapatite inoculated with cultured bone marrow cells as expermiental site, and third was filled with graft materials only as positive control. The size of every artificial bone defect was 3mm in diameter and 3mm in depth. After the every surgical intervention of animals, oral hygiene program were performed with 1.0% chlorhexidine digluconate. All of the animals were sacrificed at 2, 4, 6 weeks after surgery. For obtaining histological section, tissus were fixed in 10% Buffered formalin and decalcified with Planko - Rycho Solution for 72hr. Tissue embeding was performed in paraffin and cut parallel to the surface of mandibular body. Section in 8um thickness of tissue was done and stained with Hematoxylin - Eosin. All the specimens were observed under the light microscopy. The following results were obtained : 1. In the case of control site which has no graft material, less inflammatory cell infiltration and rapid new bone forming tendency were revealed compared with experimental groups. But bone surface were observed depression pattern on defect area because of soft tissue invasion into the artificial bone defect during the experimental period. 2. In the porous hydroxyapatite only group, inflammatory cell infiltration was prominet and dense connective tissue were encapsulated around grafted materials. osteoblastic activity in the early stage after surgery was low to compared with grafted with bone cells. 3. In the case of porous hydroxyapatite inoculated with bone cell, less inflammatory cell infiltration and rapid new bone formation activity was revealed than hydroxyapatite only group. Active new bone formation were observed in the early stage of control group. 4. The origin of new bone forming was revealed not from the center of defected area but from the surface of preexisting bony wall on every specimen. 5. In this experiment, osteoclastic cell was not found around grafted materials, and fibrovascular invasion into regions with no noticeable foreign body reaction. Conclusively, the cultured bone cell inoculated onto the porous hydroxyapatite may have an important role of regeneration of artificial bone defects of alveolar bone.