• Restorative Dentistry and Endodontics
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• v.27 no.1
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• pp.34-43
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• 2002

The purpose of this study was to compare microleakage and marginal hybrid layer in class V restorations using two one-bottle adhesives and one self-etching adhesive. Class V cavity preparations with occlusal margins in enamel and gingival margins in dentin were pre-pared on buccal and lingual surfaces of 30 extracted human molar teeth. Prepared teeth were randomly divided into three treatment groups (n=30) and restored with three adhesives and composites: Single Bond/Filtek Z-250 (Group 1), Prime&BondNT/Esthet.X (Group 2), UniFil Bond/UniFil F (Group 3). For microleakage, samples were stored in room temperature water for 24 hours, thermocycled stained with 2% methylene blue dye, sectioned into halves, scored and analysed using Mann-whitney test and Wilcoxon signed rank sum test. For marginal hybrid layer, samples were sectioned into halves, treated with 10% phosphoric acid for 5 seconds, stored in 5% NaOCL solution for 24 hours, dried and gold coated. Occlusal and gingival margins of each sample were inspected under SEM. The results of this study were as follows ; 1. Microleakage at the occlusal margins was not evident in group 1 and group 2, but it showed in group 3 (p<0.05). 2. Microleakage in group 1 and group 3 was significantly lower than in group 2 at gingival margins (p<0.05). 3. Microleakage at gingival margins was greater than at occlusal margins in group 1 and group 2, but microleakage at occlusal margins was greater than at gingival margins in group 3 (p<0.05). 4. In group 1 and group 2, no gaps at occlusal margins showed. But gaps showed in group 3. Occlusal margins were free from a hybrid layer in all groups 5. The thickness of the marginal hybrid layers was 2.5~5 $\mu\textrm{m}$ thick in group 5 $\mu\textrm{m}$ thick in group 2 and 1.5 $\mu\textrm{m}$ thick in group 3. 6 There was no corelation between microleakage and thickness of marginal hybrid layer. In coclusion, the effect of dentin adhesives on microleakge in class V composite restorations was excellent when one-bottle adhesives were applied on enamel margin, and it was good when a self-etching adhesive was applied on dentinal margin. There was no corelation between microleakage and thickness of marginal hybrid layer.

• Archives of design research
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• v.2 no.1
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• pp.13-41
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• 1989

The raw materials for plant-stalk-folkcrafts are cultivated in the whole country. Most Korean farmers, to increase their income, have produced mats and containers with various plants as a side line from very long ago. At first, they began from the instruments of life and then made folkart and at last get to manu\ulcornerfacturing of industrial folk craft. The folkcrafts, made of plant-stalk, which could nor conform to changing society, are partly declined and partly handed down as the traditions. The social change today, however, makes living conditions more speedy and multisided, accordingly the characteristics of demand also become in\ulcornerdividual and various. While the demend is various like this, suppliers cannot answer demendants' requirements, and consequently, the demand and profit cannot be increased. According to this, the purpose of this study is set up to give an answer to the situation that is at the traditional standstill, through an examination of the motives. I. The crafts of plant-stalk are made only in an organized relationship between agriculture, industry and art as it is compounded art of gathering raw material, manufacturing, producing, improv\ulcornering design and production conditions. It may be possible that a farmer gathers material and weaves it manually but in others, it is im\ulcornerpossible to refine, bleach and dye because the process requires a professional industrial treatment. It is impossible to make art works to a farmer as every farner does not always have aesthetic sense. Though a farmer or producer has these all abilities, it is not desirable to him from economical view. 2. The development or improvement is essential in many sides but the most important thing seems to he in design. According to reports, it is, howevt!r, fact that the crafts improved in design of existing works have more expanded the sales than newly developed works. Therefore, ir appears advisable to improve designs of existing things positively as they have merit of occupying a position already, but on the other hand, new crafts have to be also developed and the producer should grasp the proper time. 3. Building up an industrial complex to improve design with collecting the producing districts for this works scattered allover the country is very desirable for speedy communication, intensive educa\ulcorner tion or training, and effective guidance. 4. In producing for export abroad, before everything, must know the life environment, custom! and manners, main thought of the country, and then produce according to these. S. The crafts of plant-stalk are the fIrst industry in present but in the futher it should change intc second or third industry. 6. A synethetic organization for supporting side line should be established for effectiveness, and experts have to be secured and also the educational-industrial complex and activation of study should be preceded.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.525-533
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• 2015

The effect of the hot water extract of defatted green tea seed cake (GTSE) on lipid metabolism and the underlying mechanisms of lipolysis in mature 3T3-L1 adipocytes were investigated. In this study, we found that the naringenin content of GTSE was 5.5 mg/g; however, catechins were not detected. The intracellular lipid droplets were stained with Oil Red O dye and quantified. Compared to the control, lipid accumulation was significantly decreased by 52%, and intracellular triglyceride (TG) level was reduced by 33% after treatment with GTSE at a concentration of $40{\mu}g/mL$. To determine the mechanism of reduction in TG content, we determined the level of fatty acid synthase (FAS), phosphorylation of adenosine monophosphate-activated protein kinase (AMPK), and acetyl-coenzyme A carboxylase (ACC) in the cell model. Incubation of the 3T3-L1 adipocytes with GTSE stimulated AMPK and ACC phosphorylation in a dose-dependent manner, and decreased the expression of FAS.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.430-436
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• 2014

Allura Red (AR) is a water-soluble harmful tar-based food colorant (FD & C Red 40). Batch adsorption studies were performed for the removal of AR using bituminous coal based granular activated carbon as adsorbent by varying the operation parameters such as adsorbent dosage, initial concentration, contact time and temperature. Experimental equilibrium adsorption data were analyzed by Langmuir, Freundlich and Temkin isotherms. The equilibrium process was described well by Freundlich isotherm. From determined separation factor ($R_L$), adsorption of AR by granular activated carbon could be employed as effective treatment method. Temkin parameter, B was determined to 1.62~3.288 J/mol indicating a physical adsorption process. By estimation of adsorption rate experimental data, the value of intraparticle diffusion rate constant ($k_m$) increased with the increasing adsorption temperature. The adsorption process were found to confirm to the pseudo second order model with good correlation. Thermodynamic parameters like change of free energy, enthalpy, and entropy were also calculated to predict the nature adsorption in the temperature range of 298~318 K. The negative Gibbs free energy change (${\Delta}G$ = -2.16~-6.55 kJ/mol) and the positive enthalpy change (${\Delta}H$ = + 23.29 kJ/mol) indicated the spontaneous and endothermic nature of the adsorption process, respectively.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.997-1002
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• 1995

In order to study the effects of reaction temperature, time and particle size on the physicochemical properties of chitosan, commercially available chitin was treated with 50%(w/w) NaOH. To obtain 78% of deacetylation, a treatment of 6 hours at $100^{\circ}C$(Ch-100), 20 minutes at $120^{\circ}C$(Ch-120) or 10 minutes at $140^{\circ}C$(Ch-140) was necessary. The resulting chitosans showed a different viscosity; 180cps for Ch-100, 130cps for Ch-120, 30cps for Ch-140. The residence time at $80^{\circ}C$ also decreased the viscosity of the chitosan but the reduction in the particle size of chitin largely favored deacetylation and resulted in a higher viscosity of the chitosan. Compared with chitin, the capacity of water and oil absorption of chitosan was not significantly improved. However, the capacity of dye absorption was increased by 4 times by the deacetylation. In addition the IR spectra of chitosans showed less sharp absorption bands than that of chitin.

• Journal of Korean Medicine for Obesity Research
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• v.19 no.2
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• pp.106-112
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• 2019

Objectives: The aim of this study was to observe the reduction of lipid accumulation by treatment with Akkermansia muciniphila extract on 3T3-L1 adipocytes. Methods: After treating pasteurized Akk. muciniphila strains in HT-29 colorectal cancer cell, the relative expression of interleukin (IL)-8, tumor necrosis factor-α, IL-6, and IL-1β mRNA was analyzed by real time polymerase chain reaction, respectively. 27 strains of Akk. muciniphila which have anti-inflammatory effects were selected. 3T3-L1 pre-adipocytes were treated with Akk. muciniphila for 24 hr and then measured the toxicity using water soluble tetrazolium salt assay. The cells were incubated for 4 days and then differentiated into adipocytes using the medium including adipogenic reagents for 10 days. The Akk. muciniphila was treated when the medium was exchanged for differentiation medium at 4^th day and insulin medium at 6^th day. To observe the lipid accumulation, the cells were stained with Oil red O dye and were measured using a spectrophotometer. Results: In the cytotoxicity test, the cell viability of 3T3-L1 pre-adipocytes was significantly increased compared to the control group which untreated with Akk. muciniphila, and there was no cytotoxicity of Akk. muciniphila at 1×10⁷ CFU/mL. The results on Oil red O staining and absorbance measurements were showed a significant decrease in lipid accumulation in the group which was treated with Akk. muciniphila compared to the control group. Conclusions: In our results, Akk. muciniphila has the inhibitory effect of lipid accumulation in 3T3-L1 adipocytes. This suggests that Akk. muciniphila could be help to improve obesity.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.63-67
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• 2007

The neuroprotective effect of methanolic extracts from Dendrobium nobile Lindl. (DME) against $H_{2}O_{2}$-induced neurotoxicity in PC12 cells was investigated. The treatment of PC12 cells with various DME concentrations under $H_{2}O_{2}$ resulted in the induction of protective effect in a dose-dependent manner, as determined by the results of an MTT reduction assay, an LDH release assays, and a morphological assay. Interestingly, we also detected reduction of apoptotic bodies and inhibition of caspase-3 activity by DME in $H_{2}O_{2}$-indeced PC12 cells. These data show that the neuroprotective effect of DME against PC12 cells might be related to the suppression of caspase-3 activation. Therefore, these results suggest that DME could be a new potential candidate as chemotherapeutic agents against neuronal diseases.

• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.679-686
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• 2019

Characteristics of adsorption equilibrium, kinetic and thermodynamic of aniline blue onto activated carbon from aqueous solution were investigated as function of initial concentration, contact time and temperature. Adsorption isotherm of aniline blue was analyzed by Langmuir, Freundlich, Redlich-Peterson, Temkin and Dubinin-Radushkevich models. Langmuir isotherm model fit better with isothermal data than other isotherm models. Estmated Langmuir separation factors ($R_L=0.036{\sim}0.068$) indicated that adsorption process of aniline blue by activated carbon could be an effective treatment method. Adsorption kinetic data were fitted to pseudo first order model, pseudo second order model and intraparticle diffusion models. The kinetic results showed that the adsorption of aniline blue onto activated carbon well followed pseudo second-order model. Adsorption mechanism was evaluated in two steps, film diffusion and intraparticle diffusion, by intraparticle diffusion model. Thermodynamic parameters such as Gibbs free energy, enthalpy and entropy for adsorption process were estimated. Enthalpy change (48.49 kJ/mol) indicated that this adsorption process was physical adsorption and endothermic. Since Gibbs free energy decreased with increasing temperature, the adsorption reaction became more spontaneously with increasing temperature. The isosteric heat of adsorption indicated that there is interaction between the adsorbent and the adsorbate because the energy heterogeneity of the adsorbent surface.

• Clean Technology
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• v.25 no.1
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• pp.56-62
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• 2019

The equilibrium, kinetic and thermodynamic parameters of adsorption of murexide by granular activated carbon were investigated. The experiment was carried out by batch experiment with the variables of the amount of the adsorbent, the initial concentration of the dye, the contact time and the temperature. The isothermal adsorption equilibrium was best applied to the Freundlich equation in the range of 293 ~ 313 K. From the separation factor (${\beta}$) of Freundlich equation, it was found that adsorption of murexide by granular activated carbon could be the appropriate treatment method. The adsorption energy (E) obtained from the Dubinin- Radushkevich equation shows that the adsorption process is a physical adsorption process. From the kinetic analysis of the adsorption process, pseudo second order model is more consistent than pseudo first order model. It was found that the adsorption process proceeded to a spontaneous process and an endothermic process through Gibbs free energy change ($-0.1096{\sim}-10.5348kJ\;mol^{-1}$) and enthalpy change ($+151.29kJ\;mol^{-1}$). In addition, since the Gibbs free energy change decreased with increasing temperature, adsorption reaction of murexide by granular activated carbon increased spontaneously with increasing temperature. The entropy change ($147.62J\;mol^{-1}\;K^{-1}$) represented the increasing of randomness at the solid-solution interface during the adsorption reaction of murexide by activated carbon.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.1
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• pp.10-19
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• 2019

Morphology of cumulus-oocyte-complexes (COCs) at germinal vesicle (GV) stage as one of the evaluation criteria for oocyte maturation quality after in vitro maturation (IVM) plays important roles on the meiotic maturation, fertilization and early embryonic development in pigs. When cumulus cells of COCs are insufficient, which is induced the low oocyte maturation rate by the increasing of reactive oxygen species (ROS) in porcine oocyte during IVM. The ROS are known to generate including superoxide and hydrogen peroxide from electron transport system of mitochondria during oocyte maturation in pigs. To regulate the ROS production, the cumulus cells is secreted the various antioxidant enzymes during IVM of porcine oocyte. Our previous study showed that Mito-TEMPO, superoxide specific scavenger, improves the embryonic developmental competence and blastocyst formation rate by regulating of mitochondria functions in pigs. However, the effects of Mito-TEMPO as a superoxide scavenger to help the anti-oxidant functions from cumulus cells of COCs on meiotic maturation during porcine oocyte IVM has not been reported. Here, we categorized experimental groups into two groups (Grade 1: G1; high cumulus cells and Grade 2: G2; low cumulus cells) by using hemocytometer. The meiotic maturation rate from G2 was significantly (p < 0.05) decreased (G1: $79.9{\pm}3.8%$ vs G2: $57.5{\pm}4.6%$) compared to G1. To investigate the production of mitochondria derived superoxide, we used the mitochondrial superoxide dye, Mito-SOX. Red fluorescence of Mito-SOX detected superoxide was significantly (p < 0.05) increased in COCs of G2 compared with G1. And, we examined expression levels of genes associated with mitochondrial antioxidant such as SOD1, SOD2 and PRDX3 using a RT-PCR in porcine COCs at 44 h of IVM. The mRNA levels of three antioxidant enzymes expression in COCs from G2 were significantly (p < 0.05) lower than COCs of G1. In addition, we investigated the anti-oxidative effects of Mito-TEMPO on meiotic maturation of porcine oocyte from G1 and G2. Meiotic maturation and mRNA levels of antioxidant enzymes were significantly (p < 0.05) recovered in G2 by Mito-TEMPO ($0.1{\mu}M$, MT) treatment (G2: $68.4{\pm}3.2%$ vs G2 + MT: $73.9{\pm}1.4%$). Therefore, our results suggest that reduction of mitochondria derived superoxide by Mito-TEMPO may improves the meiotic maturation in IVM of porcine oocyte.