• Restorative Dentistry and Endodontics
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• v.28 no.1
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• pp.80-88
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• 2003

Object The purpose of this study were to evaluate the microtensile bond strength of resin fiber reinforced post to radicular dentin using resin cement according to various dentin surface treatment and to observe the inter face between post and root dentin under SEM Material and Method A total 16 extracted human single rooted teeth were used. A lingual access was made using a #245 carbide bur in a high-speed handpiece with copious air water spray. The post space was mechanically enlarged using H-file(up to #60) and Gates Glidden bures(#3). This was followed by refining of the canal space using the calbrating drill set provided in ER Dentinpost(GEBR, BRASSELER GmbH&Co. KG). The 16 teeth were randomly distributed into 4 group of 4 teeth. Group 1 teeth had their post space prepared using 10% phosphoric acid as root canal surface treatment agent during 20s. The canal was then rinsed with saline and dried with paper point. Group 2 teeth had their post space prepared using 3% NaOCl as root canal surface treatment agent during 30min. The canal was then rinsed with saline and dried with paper point. Group 3 teeth had their post space prepared using 17% EDTA as root canal surface treatment agent during 1min. The canal was then rinsed with saline and dried with paper point. Group 4 teeth had their post space prepared using 17% EDTA as root canal surface treatment agent during 1min. After rinsing with saline, the canal was rinced 10m1 of 3% NaOCl for 30min. After drying with paper point, the post(ER Dentinpost, GEBR, BRASSELER GmbH&Co. KG) was placed in the treated canals using resin cement. Once the canal was filled with resin cement(Super bond C&B sunmedical co. Ltd.), a lentulo was inserted to the depth of the canal to ensure proper coating of the root canal wall. After 24 hours, acrylic resin blocks($10{\cdot}10{\cdot}50mm$) were made. The resin block was serially sectioned vertically into stick of $1{\cdot}1mm$. Twenty sticks were prepared from each group. After that, tensile bond strengths for each stick was measured with Microtensile Tester. Failure pattern of the specimen at the interface between post and dentin were observed under SEM. Results 1. Tensile bond strengths(meen{\pm}SD$) ) were expressed with ascending order as follows group 4, $12.52{\pm}6.60$ ; group 1, $7.63{\pm}5.83$ ; group 2, $4.13{\pm}2.31$ ; group 3, $3.31{\pm}1.44$. 2. Tensile bond strengths of Group 4 treated with 17% EDTA +3%NaOCl were significant higher than those of group 1, 2 and 3 (p<0.05). 3. Tensile bond strengths of Group 1 treated with 10% phosphoric acid were significant higher than those of group 2 (p<0.05). Tensile bond strengths of Group 4 treated with 17% EDTA +3% NaOCl was significant higher than those of other groups.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.352-360
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• 2010

This study was performed to develop a Korean natural cheese with traditional medical wine, making it different from foreign natural cheese. The effects of cheese with Sasam(Codonopsis lanceolate) wine(CLW) on the quality properties during the ripening period of natural cheese were investigated. The properties investigated were growth of lactic acid bacteria, characteristics of ripening, and sensory characteristics. Four vats of cheese were made on the same day from the same tank of fresh milk. Cheese samples were prepared with CLW at 2.0%, 4.0% and 6.0% of raw milk. Changes in gross composition, viable cell counts, pH, water soluble nitrogen(WSN), non casein nitrogen(NCN), non protein nitrogen(NPN), and proteolysis during maturation were measured. Polyacrylamide gel electrophoresis(PAGE) patterns were determined with control cheese. Viable cell counts of control and CLW cheese were not significantly different. The pH of CLW cheese increased gradually during maturation, and saponin levels and levels of NPN, NCN, and WSN were higher in CLW cheeses than control cheese. For most compositional data, the 4.0% CLW cheese was most similar to the control cheese. The PAGE pattern of cheese caseins indicated that the CLW cheeses degraded more rapidly than the control cheese. Control and 2.0% CLW cheese had good sensory scores, while scores for 4.0% and 6.0% CLW cheese were lower. However, sensory data depreciated with added levels of CLW, especially at a level of 4.0% or more. Further studies on levels of CLW and processing methods are required to improve sensory quality.

• Food Science of Animal Resources
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• v.23 no.2
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• pp.128-136
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• 2003

This study was peformed to evaluate physico-chemical and textural properties, and shelf-life effect of low-fat functional sausages(LFFS) manufactured with sodium lactate(SL), lac color and various molecular weights of chitosans(low=1.5 kDa, medium=30∼40 kDa and high=200 kDa) during storage at 4$^{\circ}C$ for 8 weeks. LFFS had a pH range of 6.39∼6.50, 76∼78% moisture, <2% fat, 14∼15% protein. The combination of SL and low molecular weight(MW) of chitosan improved water holding capacity(WHC), however those of SL and medium MW of chitosan reduced WHC. Vacuum purge(VP) reduced with increased MW of chitosans during refrigerated storage. The addition of chitosans reduced the lightness and yellowness, but increased the redness values, which was comparable to the sodium nitrite concentration between 75 and 150 ppm. LFFS containing SL and medium MW of chitosan increased most texture profile analysis(TPA) values, as compared to controls with 75 and 150 ppm. The addition of SL in LFFS retarded the microbial growth for Listeria monocytogenes, however no synergistic effect with the addition of chitosans were observed. E coli O157:H7 and Salmonella typhimurium reduced during refrigerated storage, regardless of SL and chitosan treatments. Increased storage time increased values for VP, yellowness and textural properties. These results indicated that the combination of SL and various MW of chitosans affected the functional and textural properties, and inhibited the microbial growth for LM effectively. In addition, 0.5% lac color as a replacer for sodium nitrite improved the color development, resulting in similar hunter color values, which was comparable to the sodium nitrite concentration between 75 and 150 ppm.

• Journal of the Korean Society of Food Culture
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• v.20 no.6
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• pp.738-743
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• 2005

This study was performed to investigate the quality characteristics of pine mushroom yanggaeng prepared with different additions and different preparations of pine mushroom. Yanggaeng was prepared with three concentration of pine mushroom after different preparations of pine mushroom, A hot wind drying 0.1%, 0.3%, 0.5%, Frozen pine mushroom grinding 0.1%, 0.3%, 0.5%, Freezed drying 0.1%, 0.3%, 0.5%, to which was added cooked red bean, agar, oligosaccharide, salt and water. Proximate composition, hunter's color, texture profile analysis and sensory evaluation of yanggaeng were examined. Lightness of pine mushroom yangaeng increased with increasing pine mushroom content and frozen pine mushroom grinding products were higher than those of the preparation products. In the texture profile analysis, hardness of pine mushroom yangaeng increased with increasing pine mushroom content and cohesiveness, springiness of Frozen pine mushroom grinding 0.1% were the highest. In sensory evaluation, the taste and viscosity scores of Freezed drying 0.1% higher than those of the other products. Also the overall acceptability of freezed drying 0.1% pine mushroom yanggaeng was the highest of the all products.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.282-291
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• 2006

Effects of the molecular weight and type of chitosans on shelf-life of Makkulli were evaluated during 18 days of storage at $25^{\circ}C$. Two types of chitosans were studied: ${\alpha}$-chitosans with 11 different molecular weights (water-soluble, Mw = 1, 8, 22, 43, 67 and 616 kDa; acid-soluble, Mw = 282, 440, 746, 1,110 and 2,025 kDa) and ${\beta}$-chitosan (acid-soluble, Mw = 577 kDa). Acid-soluble chitosans were applied as a form of chitosan-ascorbate. All chitosans were added to Makkulli at 0.002% concentration, the optimum concentration established in a preliminary test. Among 12 chitosans, the ${\alpha}$-chitosans with 22 and 440 kDa exhibited stronger antimicrobial effects than did other ${\alpha}$- and ${\beta}$-chitosans. The results for pH, acidity, alcohol concentration, viable cell counts, and sensory evaluation suggested that addition of ${\alpha}$-chitosans with 22 and 440 kDa increased the shelf-life of Makkulli by almost 1 week at $25^{\circ}C$ compared with that of control (without chitosan) and other chitosan-added groups. Extension of Makkulli shelf-life by 1 week is fairly significant in view of the magnitude of the total amount of Makkulli produced in Korea.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.4
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• pp.295-300
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• 2015

Purpose: The aim of this study was to evaluate the shear bond strength between Ni-Cr alloy and composite resin using universal adhesive systems coMPared to conventional method using metal primers. Materials and methods: For this study, a total of 120 cast commercial Ni-Cr alloy (Vera Bond 2V) disks were embedded in acrylic resin, and their surfaces were smoothed with silicon carbide papers and airborne-particle abrasion. Specimens of each metal were divided into 6 groups based on the combination of metal primers (Metal primer II, Alloy primer, Metal & Zirconia primer, MKZ primer) and universal adhesive systems (Single Bond Universal, All Bond Universal). All specimens were stored in distilled water at $37^{\circ}C$ for 24 hours. Shear bond strength testing was performed with a universal testing machine at a cross head speed of 1 m/min. Data (MPa) were analyzed using one-way ANOVA and the post hoc Tukey's multiple comparison test (${\alpha}$=.05). Results: There were significant differences between Single Bond Universal, All Bond Universal, Metal Primer II and Alloy Primer, MKZ Primer, Metal & Zirconia Primer (P<.001). Conclusion: Universal Adhesive system groups indicated high shear bond strength value bonded to Ni-Cr alloy than that of conventional system groups using primers except Metal Primer II. Within the limitations of this study, improvement of universal adhesive systems which can be applied to all types of restorations is recommended especially non-precious metal alloy. More research is needed to evaluate the effect of silane inclusion or exclusion in universal adhesive systems.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.14-20
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• 2006

In this study, the feasibility of simultaneous removal of organic materials and nitrogen in the waste-water from fisheries processing plant was evaluated using entrapped mixed microbial cell technique(EMMC) process. The experiment was performed using activated sludge from municipal sewage treatment plant which was immobilized with gel matrix by cellulose triacetate. It was found that the stable operation at the treatment system which is composed of anoxic and oxic tank, was possible when the organic and nitrogen loading rates were increased stepwise. The organic and nitrogen loading rates were applied from 0.65 to $1.72kgCOD/m^3/d$ and from 0.119 to $0.317kgT-N/m^3$ with four steps, respectively. The maximum nitrogen loading rate which could satisfy the regulated effluent standard of nitrogen concentration, was $0.3kgT-N/m^3/d$. The removal efficiency of total nitrogen was decreased apparently as increasing nitrogen loading rates, whereas the removal efficiency of ammonium nitrogen was effective at the all tested nitrogen loading rates. Therefore, it was concluded that nitrification was efficient at the system. Nitrate removal efficiency ranged from 98.62% to 99.51%, whereas the nitrification efficiency at the oxic tank ranged 94.0% to 96.9% at the tested loading rates. The removal efficiencies of chemical oxygen demand(COD) and those of total nitrogen at the entire system ranged from 94.2% to 96.6% and 73.4% to 83.4%, respectively.

• Food Science and Preservation
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• v.24 no.2
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• pp.254-265
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• 2017

For the production of ${\gamma}-aminobutyric$ acid (GABA) contents increased Seomaeyaksuk fermentant, 0, 0.25, 0.5 and 1.0% of monosodium galutamate (MSG) was added in Seomaeyaksuk water extract 15% contained Sikhye and inoculated with Lactobacillus brevis (KI271266). Physicochemical properties were sampling and analyzed at each 1 day during 3 days fermentation. Goes on fermentation periods, the turbidity was gradually reduced, but lightness and the yellowness was increased, redness was decreased. Soluble solid was also decreased. The reducing sugars content were also decreased during fermentation. pH was 4.65-4.83 before fermentation but it was lower 3.15-3.68 after three days fermentation. The GABA contents increased by fermentation periods and it was the highest in MSG 1.0% added sample (354.38 mg/L). Fructose, glucose and sucrose contents were 50-67% decreased at three days fermentation than before fermentation. Among the organic acids, propionic acid, oxalic acid, citric acid and fumaric acid contents were decreased and lactic acid, acetic acid and succinic acid were increased during fermentation periods. Contents of total polyphenol and DPPH radical scavenging activity were the highest in MSG 0.5% added sample. From these results, we confirmed that increasing of GABA content when the manufacturing of Seomaeyaksuk lactic acid fermentation product, is possibile by addition of MSG without affecting physicochemical characteristics.

• Clean Technology
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• v.18 no.3
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• pp.272-279
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• 2012

In this study, an environmental-friendly cleaning agent utilizing organic acids and various additives has been developed and applied to the field for removal of scale deposited on the cleaning beds or distribution reservoirs of the waterworks. As an analytical result of scale on the cleaning beds, we found that it consists of mainly metallic oxides such as $SiO_2$, $Al_2O_3$, $Fe_2O_3$, and MnO. Malic acid, malonic acid, and citric acid showed relatively better solvency on $Al_2O_3$, $Fe_2O_3$, and MnO except $SiO_2$ among various organic acids. Mixed organic acid solutions of malic acid, malonic acid, and citric acid were prepared with certain weight ratios and their solvencies on mixed metal oxides of $Al_2O_3$, $Fe_2O_3$, and MnO were investigated. The experimental results showed that an 10% mixed organic acid solution prepared with weight ratio of malic acid : malonic acid : citric acid = 6 : 2 : 2 were found to have best scale solvency power of about 29%. The formulated cleaning agents with a small amount of nonionic surfactant showed much better solvency on mixed oxides than mixed organic solution alone. Especially, the formulated cleaning agent with 0.2 wt% LA-7 surfactant appeared to have best scale removal efficiency of about 35%. However, the formulated cleaning agent with disinfectants such as NaClO, $H_2O_2$ and $Ca(ClO)_2$ showed poor solvency on mixed oxides. It is inferred that surfactants are able to improve scale removal efficiency due to their capability of emulsification, and disinfectants cause to degrade scale solvency in water because of their oxidation. Based on these basic experimental results, formulated cleaning agents have been prepared with mixed organic acid solution, nonionic surfactants, and disinfectants and successfully applied to removal of scales on the cleaning beds and distribution reservoir at city D waterworks.

• Korean Journal of Poultry Science
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• v.39 no.3
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• pp.167-175
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• 2012

This study was undertaken to assess dietary CP and ME concentrations for optimum growth performance and carcass characteristics of Korean Native male ducks. In a $3{\times}3$ factorial arrangement, 1-d-old Korean Native male ducks were completely randomized design to experimental diets with 3,000, 2,900, and 2,800 kcal of ME/kg of diet; each contained 23, 22, and 21% CP, respectively, from 0 to 3 wk of age. From 4 to 8 wk of age, experimental diets had 3,100, 3,000, and 2,900 kcal of ME/kg of diet, and each contained 19, 18, and 17% CP, respectively. Each dietary treatment was replicated 4 times, and feed and water were provided ad libitum. Body weight, feed intake and uniformity were measured at 3 wk and 8 wk, and carcass characteristics were evaluated at 8 wk. As CP increased from 21 to 23 %, the body weight, BW gain and feed conversion ratios (FCR) linearly improved (P<0.01) during 0 to 3 wk of age. From 4 to 8 wk of age, the body weight, feed intake, BW gain, FCR and uniformity were not different (P>0.05). Carcass ratios of birds fed 3,000 kcal of ME/kg diets from 3 to 8 wk of age were quadratically increased significantly (P<0.01). As ME and CP increased, respectively, relative weight of liver weight per 100 g of BW was linearly decreased (P<0.01). Relative weights of left breast, thigh and drumstick weight per 100 of BW were not different (P>0.05). Also, breast meat color, pH, cooking loss and shear force were not different (P>0.05). Thus, diets with 2,800 kcal of ME/kg and 23% CP or with 2,900 kcal of ME/kg and 17% CP at 0 to 3 wk and 4 to 8 wk, respectively, were used more efficiently. However, diets with 3,000 kcal of ME/kg at 4 to 8 wk in carcass rate was quadratically increased.