• Polymer(Korea)
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• v.37 no.2
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• pp.156-161
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• 2013

Phenolic antioxidants are effective stabilizers that provide excellent long-term heat stability by preventing thermo-oxidative degradation during processing and service life. However, under a selected set of circumstances, certain types of phenolics have been susceptible to discoloration due to prolonged storage in an environment containing oxides of nitrogen. It is investigated that the effect of addition of secondary antioxidant and chemical structure of primary antioxidant on discoloration of amorphous poly-${\alpha}$-olefin (APAO), which is especially prone to be decomposed in high processing temperature. From the result, it is concluded that a higher level of steric hindrance of phenolic antioxidant provided by long alkyl chain allows a more enhanced synergic effect with secondary antioxidant.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.2
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• pp.155-161
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• 2021

This study was attempted to investigate natural materials with antimicrobial activity and to apply as natural preservatives in cosmetics. The disc diffusion method was used to search for nine species of natural antibacterial material for three species of skin pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa) and Candida albicans. As a result of measuring the size of inhibition zone, Rhus Semialata gall (Gallnut) extract, Oak vinegar, and ε-polylysine were showed strongest antibacterial activities (> 10 mm). The Minimum Bactericidal Concentration (MBC) of gallnut and oak vinegar ranged from 10 to 20 mg/mL and from 20 to 40 mg/mL against five human skin pathogens. The MBC of ε-polylysine ranged from 0.5 to 2 mg/mL in fungus. The synergic effect of gallnut extract/oak vinegar mixture and gallnut extract/ε-polylysine mixture were evaluated by checkerboard test. Compared to when used alone, the MBC of gallnut extract/oak vinegar mixture were at 4 times lower concentration against E. coli, C. albicans, and A. brasiliensis. Also Furthermore, the MBC of gallnut extract/ε-polylysine mixture were at 4 times lower concentration against C. albicans and A. brasiliensis. It was confirmed that the combination of gallnut extract with oak vinegar or ε-polylysine resulted in synergistic antibacterial effect against three human skin pathogens. Thus, it is expected that gallnut extract and natural product mixture can not only demonstrate antibacterial synergies, but also be applied in cosmetics as a natural preservative system with a wide antibacterial spectrum.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.81-88
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• 2011

The anti-phytoplasma activities of surfactin (derived from Iranian native Bacillus subtilis isolates) and tetracycline towards Candidatus "Phytoplasma aurantifolia", the agent of lime Witches' broom disease, were investigated. HPLC was used to quantify the surfactin production in four previously characterized native surfactin-producing strains, and the one producing the highest amount of surfactin (about 1,500 mg/l) was selected and cultivated following optimized production and extraction protocols. Different combinations of purified surfactin and commercial tetracycline were injected into artificially phytoplasmainfected Mexican lime seedlings using a syringe injection system. An absolute quantitative real-time PCR system was developed to monitor the phytoplasma population shifts in the lime phloem during 3 months following the injections. The results revealed that the injections of surfactin or tetracycline had a significant inhibitory effect on Candidatus "P. aurantifolia". However, the combined treatment with both surfactin and tetracycline (1:1) resulted in the highest inhibition due to a synergic effect, which suppressed the phytoplasma population from about $2{\times}10^5$ to less than 10 phytoplasma units/g plant tissue.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.2
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• pp.37-49
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• 2014

Purpose: This study compares the bone formation ability of tricalcium phosphate (TCP) with and without recombinant human bone morphogenetic protein-2 (rhBMP-2) and assesses TCP as a carrier of rhBMP-2. Methods: Bilateral round defects (diameter: 8.0 mm) were formed in the cranium of eight New Zealand white rabbits. The defects were grafted with TCP only (control group) or with rhBMP-2-coated TCP (experimental group). The animals were sacrificed at 1st week, 2nd week, 4th week, and 8th week postoperatively; two rabbits sacrificed each time. The skulls were harvested and subjected to radiographic and histological examination. Results: Radiologic evaluation showed faster bone remodeling in the experimental group than in the control group. Histologic evaluation (H&E, Masson's trichrome stain) showed rapid bone formation, remodeling and calcification in the 1st and 2nd week in the experimental group. Immunohistochemical evaluation showed higher expression rate of osteoprotegerin, receptor activator of nuclear factor ${\kappa}B$ ligand, and receptor activator of nuclear factor ${\kappa}B$ in the experimental group at the 1st and 2nd week than in the control group. Conclusion: rhBMP-2 coated TCP resulted in rapid bone formation, remodeling, and calcification due to rhBMP-2's osteogenic effect. TCP performed properly as a carrier for rhBMP-2. Thus, the use of an rhBMP-2 coating on TCP had a synergic effect on bone healing and, especially, bone remodeling and maturation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.3
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• pp.98-104
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• 2015

Titanium barrier membranes are prepared to investigate the effect of surface-treatments, such as machining, electropolishing, anodizing, and electropolishing + TiN coating, on the biocompatibility and physical properties of the membranes. The surface roughness (Ra) of the membrane decreases from machining ($0.37{\pm}0.09{\mu}m$), TiN coating ($0.22{\pm}0.09{\mu}m$), electropolishing ($0.20{\pm}0.03{\mu}m$), to anodizing ($0.15{\pm}0.03{\mu}m$). The highest ductility (24.50 %) is observed for the electropolished Ti membrane. No evidence of causing cell lysis or toxicity is found for the membranes regardless of the surface-treatments. Cell adhesion results of L-929 and MG-63 show that the machined Ti membrane exhibits the highest cell adhesion while the electropolished membrane is the best membrane for the L-929 cell proliferation after 7 days. However, no appreciable difference in MG-63 cell proliferation among variously surface-treated membranes is detected, suggesting that the electropolished Ti membrane is likely to be the best membrane due to the synergic combination of tailored flexibility and excellent fibroblast proliferation.

• Culinary science and hospitality research
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• v.7 no.3
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• pp.13-34
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• 2001

The case which it contracts with the dynamic result measurement system when actual outsourcing evaluation measurement is composed and then one result standard between the service supplier and the user is set, which owns jointly the expense which is reduced from that or the benefit which is created from that is increasing In the conclusion, for outsourcing management strategy of domestic foodservice industry in order to succeed, first it is accurate and examined that for what and how outsourcing should be introduced and as a result, what kind of result can be raised from that result\ulcorner Food service industry should be outsourced if you want to make more many investment in better humane resources, food & beverage-goods-security and education to provide eating-out service out of various business in food industry. When considering the actuality of the domestic foodservice industry that time it is appropriate, it sees. The foreign-brand goods which is introduced in the country are being executing in the 1ink of part management strategy. One of the most influential factor of domestic foodservice industry's management pressure is overspent management expenses, Does the namely expenses preparation effect reach which degree\ulcorner what kind of method can most decrease these expenses\ulcorner Doing grows the success and failure of the Korean foodservice industry controls result with the fact that it will operate with a big variable sees. The background which the domestic foodservice industry should introduce inevitably the outsiurcing system is to develop continuously nation foodservice industry in the way of cost curtailment of food-material, a labor cost curtailment with efficient application and synergic effect like specialty manpower utilization. The kindred competitive enterprises gradually concentrate management resource to the point ability from the present point of view which is increasing and a strategy position they secure, to prepare a competitive power, what sees it is important national industry must prepare a new paradigm. It is important to measure the result based on sales accomplishment in operation system dimension, and it is more important to appropriately apply regard of the evaluation measurement

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.99-107
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• 1998

Numerous studies have demonstrated a negative association between cigarette smoking and Parkinson's disease. The present study was undertaken to investigate whether chronic exposure of mice to cigarette smoke a(footed the metabolism of 1-methyl-1113,6-tetrahydro-pyridine (MPTP) by cytochrome P4SO (P-450) or flavin-containing monooxygenase (FMO) in the hepatic microsomes of C57BL6/J mice. Adult male C57BL6/J mice were exposed to mainstream smoke generated from 15 cigarettes for 10 min a day and 5 day per week for 6 weeks. MPTP (10 mg/kg body weight) was administered to mice by subcutaneous injection for 6 consecutive days. Microsolnal P-450 content was increased by MPTP, smoke exposure, or both, but NADPH cytochrome P-450 reductase activity was rather decreased by the same treatments. The activities of benzo(a)pyrene hydroxylase, 7-ethoxycoumarin O-deethylase and ethoxyresorufin O-deethylase were significantly increased by the exposure of cigarette smoke, but were not or little affected by MPTP treatment. Benzphetamine N-demethylase activity was not affected either by MPTP treatment or by cigarette smoke exposure, but it was significantly increased by the combined MPTP treatment with cigarette smoke exposure, showing their synergic effect for the induction of the enzyme activity. Interestingly, in vitro studies of hepatic FMO and P-450 system both O-oxygenation and N-demethylation of MPTP were increased in the smoke-exposed or in the MPTP-treated mice. These results suggest that the enhancement in the N-demethylation as well as O-deethylation of P-450 system and in the N-oxygenation of FMO activity by cigarette smoke exposure in mouse liver may contribute to attenuating the neurotoxic effects of MPTP on the nigrostriatal dopaminergic neurons.

• Journal of Welding and Joining
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• v.32 no.5
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• pp.44-49
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• 2014

The effect of weldbond hybrid joining process on the mechanical behavior of single lap and L-tensile joints was investigated for the newly developed 1.2GPa grade ultra high strength TRIP(transformation induced plasticity) steel. In the case of single lap shear behavior, the weldbond joint of 1.2GPa TRIP steel showed lower maximum tensile load and elongation than that of the adhesive bonding only. It was considered to be due to the reduction of real adhesion area, which was caused by the degradation of adhesive near the spot weld, and the brittle fracture behavior of the spot weld joint. In the case of L-tensile behavior, however, the maximum tensile load of the weldbond joint of 1.2GPa TRIP steel was dramatically increased and the fracture mode was change to the base metal fracture which is desirable for the spot weld joint. These synergic effect of the weldbond hybrid joining process in 1.2GPa TRIP steel was considered to be due to the stress dissipation around the spot weld joint by the presence of adhesive which resulted in the change of crack propagation path.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.16.1-16.7
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• 2015

Background: This study aimed to investigate new bone formation using recombinant human bone morphogenetic protein 2 (rhBMP-2) and locally applied bisphosphonate in rat calvarial defects. Methods: Thirty-six rats were studied. Two circular 5 mm diameter bony defect were formed in the calvaria using a trephine bur. The bony defect were grafted with $Bio-Oss^{(R)}$ only (group 1, n = 9), $Bio-Oss^{(R)}$ wetted with rhBMP-2 (group 2, n = 9), $Bio-Oss^{(R)}$ wetted with rhBMP-2 and 1 mM alendronate (group 3, n = 9) and $Bio-Oss^{(R)}$ wetted with rhBMP-2 and 10 mM alendronate (group 4, n = 9). In each group, three animals were euthanized at 2, 4 and 8 weeks after surgery, respectively. The specimens were then analyzed by histology, histomorphometry and immunohistochemistry analysis. Results: There were significant decrease of bone formation area (p < 0.05) between group 4 and group 2, 3. Group 3 showed increase of new bone formation compared to group 2. In immunohistochemistry, collagen type I and osteoprotegerin (OPG) didn't show any difference. However, receptor activator of nuclear factor ${\kappa}B$ ligand (RANKL) decreased with time dependent except group 4. Conclusion: Low concentration bisphosphonate and rhBMP-2 have synergic effect on bone regeneration and this is result from the decreased activity of RANKL of osteoblast.

• KSBB Journal
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• v.19 no.1
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• pp.88-92
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• 2004

The immunogenicity of investigational combined vaccine, composed of the Japanese encephalis virus(JEV) and the polysaccharide capsule(Vi) of Salmonella typhi covalently bound to tetanus toxoid(TT) was evaluated in mice. The mice immunized with combined vaccine elicited higher anti-Vi Immunoglobulin G(IgG) as well as anti-JEV IgG levels than the mice immunized with Vi-TT or JEV alone. The combined vaccine produced four-fold increase in anti-Vi IgG level than Vi-TT alone. In JEV the combined vaccine was significantly more immunogenic than JEV alone and induced six-fold increase in IgG level. Adsorption of combined vaccine onto aluminium hydroxide gel also enhanced IgG level for both Vi and JEV.