• The Journal of Korean Academy of Prosthodontics
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• v.40 no.5
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• pp.451-469
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• 2002

The purpose of this study was to estimate the effect of a bleaching agent on tooth surfaces and to evaluate the resin bond strength according to different surface treatments on bleached teeth. To prepare for the experimental samples, first, extracted human third molars were used and the body portions of the crowns were cut into four equal-sized specimens. Next, each specimen was mounted in an plastic bottle with self-cured resin and highly polished to have them reveal the enamel or dentin surfaces. Then, the enamel(E) and dentin(D) specimens were divided into four ; 1) non-bleached, laser-treated(NBLA) group 2) bleached, laser-treated(BLLA) group 3) non-bleached, acid-treated(NBAC) group and 4) bleached, acid-treated(BLAC) group. Here, $opalescence^{(R)}$ (10% carbamide peroxide) was used for bleaching agent. The treated specimens were observed by confocal laser scanning microscopy and bonded with composite resin for shear bond test. The following results were obtained from this experiment : 1. Compared with the ENB group, the EBL group was shown be dyed about $20{\mu}m$ deeper with rhodamine B. The DBL group appeared to be caved in at the entry part of the dentinal tubules, was dyed about $20{\mu}m$ deeper and $5{\mu}m$ wider in diameter, compared with the DNB group. 2. In comparison with the EBLAC group, the ENBAC group looked evenly bonded with the resin, while the DNBAC group, compared to DBLAC group, was observed to have its resin tags penetrated about $50{\mu}m$ deeper. Other than those, however, no observable differences between ENBLA and EBLLA group or between DNBLA and DBLLA group were found. 3, At the shear bond test, the ENBAC group was shown to have statistically significant higher shear bond strength than the EBLAC group(p<0.05). No statistically significant differences between the ENBLA and the EBLLA groups were observed(p>0.05). 4. At the shear bond test, the DNBAC group was shown to have statistically significant higher shear bond strength than the DBLAC group(p<0.05). No statistically significant differences between the DNBLA and the DBLLA groups were observed(p>0.05). The in vitro observations above suggest that tooth-bleaching procedure brings a certain change on enamel and dentin surfaces and it weakens the shear bond strength with composite resin when the bleached tooth was acid-treated.

• The Korean Journal of Mycology
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• v.39 no.1
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• pp.39-43
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• 2011

A new cultivar "Dan Bi" of Pleurotus eryngii was developed by the method of mono-mono crossing between monokaryotic strains derived from KNR2312 and KNR2596. The parental strains, KNR2312 and KNR2596, are characterized by the property of high quality and a small number of primordia formation, respectively. The optimum temperature of mycelial growth was 25 and that of fruiting body development was $15{\sim}16^{\circ}C$. The period of harvesting including primordia formation was 0.7~1.3 days later than that of control strain Knneutari No. 3 in the culling cultivation. The color of pileus and stipe surface was neutral-brown and pure white, respectively. The shape of pileus was dome and has a scale like as cobweb. The yield was $93{\pm}9.7$ g per 850 cc of plastic bottle. Analysis of the genetic characteristics of the new commercial variety "Dan Bi" showed a different profile as that of the control strain, Knneutari No. 3, when RAPD (Random Amplified Polymorphic DNA) primer #8005 was used. This new variety "Dan Bi" of Pleurotus eryngii is characterized by a small number of primordia formation after scratching.

• Korean Journal of Animal Reproduction
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• v.20 no.2
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• pp.101-109
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• 1996

This study was done to find out the methods of long-term use of liquid boar semen in 100 ml plastic bottle for artificial insemination and to investigate differences between Lactose-Egg yolk and Biitschwiler diluents according to storage temperature, and effect of final glycerol concent ration in Lactose-Egg yolk diluent. Liquid boar semen diluted with Lactose-Egg yolk diluent showed significantly higher sperm motility (p<0.05) after 0.5 and 2h incubation at 37$^{\circ}C$,than Butschwiler diluent at all storage length when it was preserved in the 5$^{\circ}C$ refrigerator. The NAR acrosome in Lactose-Egg yolk diluent a after 0.5 and 2h incubation at 37$^{\circ}C$, respectively, during preservation periods was similar to that in Biitschwiler diluent. When liquid boar semen was preserved at 15$^{\circ}C$, liquid boar semen in the Butschwiler diluent showed significantly higher percentages of sperm motility and NAR acrosome from third day to seventh than that in Lactose-Egg yolk diluent. In the effect of final glycerol concentration of liquid boar semen in the Lactose-Egg yolk diluent, the final glycerol concentration of 2% showed higer percentages of sperm motility and NAR acrosome than that of 0, 1, 3, and 5%. Farrowing rate, litter size and average pig weight at birth did not differ significantly between Lactose-Egg yolk and But schwiler diluents. As a result of this study, we found out that liquid boar semen can be stored for 6-7 days at 5$^{\circ}C$ in Lactose-Egg yolk diluent and at 15$^{\circ}C$ in Butschwiler diluent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1611-1618
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• 2005

The microbiological examinations were conducted for the hygienic evaluation on three Korean restaurants during summer season in Busan, Korea. Total one hundred and sixty swabbed samples using sponge were collected from the surface of facilities and utensils at restaurants and total and coliform counts were measured. Also thirty- six air samples were collected at inside of three restaurants for measuring total, coliform, Staphy-lococcus and mold and yeast counts. All collected samples kept in an ice-packed box were transported to the laboratory and analyzed. The results demonstrated that most swabbed samples were highly contaminated with microorganisms and coliforms. The degree of contamination depended on the sampling sites. Averages of total counts of surface swab samples were ranged from not detectable to 2.14$\times\10^{9}$/200 $cm^{2}$, while those of coliforms from not detectable to 8.34$\times\10^{7}$/200 $cm^{2}$/200 $cm^{2}$. Microorganisms also detected from most agar strips of air samples for total, coliform, Staphylococcus and mold and yeast counts. The severely contaminated sites were floor, trench, water bottle, plastic drainer, rubber gloves, shelves, and unsealed wet towel. Those sites should be focused and controlled according to control Points of sanitation standard operating Procedures. Also, periodic microbiological examination in addition to visual examination should be applied on those highly contaminated sites for reducing risk of foodborne disease outbreak at restaurants

• Journal of the Korean Institute of Gas
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• v.18 no.5
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• pp.47-51
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• 2014

This paper is to analyze and study the fire examples in respect of intake and exhaust, alternator tuning and inflow of inflammables on exhaust part in a car. In the first example, the driver diverted the intake and exhaust system for tuning of a car. Stopping a car to rest for moment, the flammable styrofoam scrap go into exhaust pipe that installed with exhaust manifold newly. It certified the fact that catched fire gradually, furthermore enlarged the fire by leaking fuel. In the second example, the driver enlarged the generator performance to divert the audio system in side room., it knew the fact that the electric wiring connected with generator gave the cause of outbreak a fire by overheating. In the third example, the serviceman replaced the engine oil using funnel-shaped, he put the a bottle of plastic pat onto engine cover carelessly. Consequentially, it found the fire occurrence in the engine room. Therefore, the driver never divert the intake and exhaust and generator construction of a car abnormally. Also, repairing and inspecting a car, the serviceman have a care to not occur the fire by inflammables.

• The Korean Journal of Nuclear Medicine
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• v.33 no.4
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• pp.430-438
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• 1999

Purpose: We evaluated a rapid preparation procedures for the labeling and quality control of $^{99m}Tc$-ECD, $MAG_3$, and MIBI using microwave heating and Sep-Pak cartridges. Materials and Methods: $^{99m}Tc$ labeling of ECD, $MAG_3$, and MIBI kit preparation was performed according to the package inserts with microwave heating modification. Heating time was 10-15 sec, and heating was performed with 3 mm plastic bottle with screw cap to prevent radiation contamination. Labeling efficiency was obtained with $C_{18}$ or Alumina N Sep-Pak cartridges. Results: The radiochemical purity of $93{\sim}96%$ for $^{99m}Tc$-ECD and $95{\sim}99%$ for $^{99m}Tc$-MIBI was obtained using Alumina N Sep-Pak cartridge. The optimum irradiation time of microwave method for 3 ml $^{99m}Tc$-labeled radiopharmaceutical solution was 10 sec for $^{99m}Tc$-ECD and $^{99m}Tc$-MIBI, and 15 sec for $^{99m}Tc-MAG_3$. The results of quality control data with Sep-Pak cartridges were well correlated with TLC method. The total preparation time of these radiopharmcaeuticals was $5{\sim}6min$ including quality control procedure. Conclusion: This study demonstrates that radiopharmaceuticals preparation by microwave heating and quality control by Sep-Pak cartridges can be efficiently utilized as an alternative to the recommended method by manufacturer's manual.

• Journal of the Korean Society of Food Culture
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• v.15 no.2
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• pp.147-153
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• 2000

A survey on the preferences and notion about kimchi and kimchi products was conducted from july to october, 1999 to investigate basic information for increasing the consumption of kimchi for sale. 1,241 subjects of women and men aged 10 to 60 in Kyung-nam area participated in this survey. Most of the subjects made kimchi by themselves at home but this rate of making kimchi at home became lower than past, so increment of consumption of kimchi for sale will be expected in the future. When the people buy kimchi, they considered taste first, and then hygiene, nutrition in order. When they purchase kimchi, more men (69.1%) than women(56%) considered taste, but more women(36.1%) than men(20.6%) considered hygiene first. Subjects aged 30 or older groups considered more the hygiene of kimchi than the subjects of $10{\sim}20$ age groups did.(p<0.05) And people of household income over 3 million wons considered more hygiene than people of below 1 million wons income group did. People liked manufactured kimchi the packed with whole or partly transparent material in order to observe the contents.(p<0.05) They liked better kimchi packed with bottle(46.1%) and vinyl(39.6%) than plastic(14.3%) and this tendency was more in the subjects of women(49.8%) and over 30 age groups.(p<0.05) They prefered $200{\sim}500g$ packing unit of kimchi whether the family size were big or small. Among the processed kimchi products, men liked better a rice covered up with kimchi, a pot stew with kimchi or a soup with kimchi, On the other hand, women liked better a dumplings with kimchi, a grilled food with kimchi, a pizza with kimchi.(p<0.05) Subjects aged 10 to 20 years old liked all kinds of kimchi products, but people aged 40 or older disliked them.(p<0.001)

• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.835-841
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• 2023

The aim of this study is to evaluate the diagnostic ability of dual-energy computed tomography (DECT) for Composition determination of urinary stones in phantom model. Seventeen cases with urinary stones who underwent DECT were enrolled in the study. The composition of the urinary stones was extracted from the seventeen patients were analyzed with DECT in phantom model with fresh pork. The volume scan method using Dual-energy software was used and the scanned image sets were assessed. All 17 urinary stones of the phantom model were analyzed according to the stone composition using DE stone Analysis were divided into uric acid stones (n=6, 35.29%) and non-uric acid stones (n=11, 64.71%). These urinary stones were pathologically confirmed. The mean attenuation values of uric acid stones at 135 kV, 100 kV and 80 kV was 348.87 ± 166.37 HU, 345.33 ± 151.18 HU and 337.94 ± 172.77 HU, respectively. The mean attenuation values of non-uric acid stones at 135 kV, 100 kV and 80 kV was 551.93 ± 297.09 HU, 747.04 ± 351.31 HU and 958.19 ± 424.72 HU, respectively. At 80 kV, uric acid stones and non-uric acid stones showed significant difference in the attenuation values(P<0.05). The attenuation values of DECT could differentiate the compositions of urinary stones between uric acid and non-uric acid stones at 80 kV in phantom model.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.5
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• pp.375-395
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• 2006

Purpose: Lingual nerve (LN) damage may be caused by either tumor resection or injury such as wisdom tooth extraction, Although autologous nerve graft is sometimes used to repair the damaged nerve, it has the disadvantage of necessity of another operation for nerve harvesting. Moreover, the results of nerve grafting is not satisfactory. The nerve growth factor (NGF) is well-known to play a critical role in peripheral nerve regeneration and its local delivery to the injured nerve has been continuously tried to enhance nerve regeneration. However, its application has limitations like repeated administration due to short half life of 30 minutes and an in vivo delivery model must allow for direct and local delivery. The aim of this study was to construct a well-functioning $rhNGF-{\beta}$ adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with enhanced and extended secretion of hNGF from the injured nerve by injecting $rhNGF-{\beta}$ gene directly into crush-injured LN in rat model. Materials and Methods: $hNGF-{\beta}$ gene was prepared from fetal brain cDNA library and cloned into E1/E3 deleted adenoviral vector which contains green fluorescence protein (GFP) gene as a reporter. After large scale production and purification of $rhNGF-{\beta}$ adenovirus, transfection efficiency and its expression at various cells (primary cultured Schwann cells, HEK293 cells, Schwann cell lines, NIH3T3 and CRH cells) were evaluated by fluorescent microscopy, RT-PCR, ELISA, immunocytochemistry. Furthermore, the function of rhNGF-beta, which was secreted from various cells infected with $rhNGF-{\beta}$ adenovirus, was evaluated using neuritogenesis of PC-12 cells. For in vivo evaluation of efficacy of $rhNGF-{\beta}$ adenovirus, the LNs of 8-week old rats were exposed and crush-injured with a small hemostat for 10 seconds. After the injury, $rhNGF-{\beta}$ adenovirus($2{\mu}l,\;1.5{\times}10^{11}pfu$) or saline was administered into the crushed site in the experimental (n=24) and the control group (n=24), respectively. Sham operation of another group of rats (n=9) was performed without administration of either saline or adenovirus. The taste recovery and the change of fungiform papilla were studied at 1, 2, 3 and 4 weeks. Each of the 6 animals was tested with different solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) by two-bottle test paradigm and the number of papilla was counted using SEM picture of tongue dorsum. LN was explored at the same interval as taste study and evaluated electro-physiologically (peak voltage and nerve conduction velocity) and histomorphometrically (axon count, myelin thickness). Results: The recombinant adenovirus vector carrying $rhNGF-{\beta}$ was constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis. GFP expression was observed in 90% of $rhNGF-{\beta}$ adenovirus infected cells compared with uninfected cells. Total mRNA isolated from $rhNGF-{\beta}$ adenovirus infected cells showed strong RT-PCR band, however uninfected or LacZ recombinant adenovirus infected cells did not. NGF quantification by ELISA showed a maximal release of $18865.4{\pm}310.9pg/ml$ NGF at the 4th day and stably continued till 14 days by $rhNGF-{\beta}$ adenovirus infected Schwann cells. PC-12 cells exposed to media with $rhNGF-{\beta}$ adenovirus infected Schwann cell revealed at the same level of neurite-extension as the commercial NGF did. $rhNGF-{\beta}$ adenovirus injected experimental groups in comparison to the control group exhibited different taste preference ratio. Salty, sweet and sour taste preference ratio were significantly different after 2 weeks from the beginning of the experiment, which were similar to the sham group, but not to the control group.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.216-222
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• 2014

The purpose of this study was to know the seed longevity of rice (Oryza sativa L.) germplasm for effective viability monitoring. The longevity was determined via germination tests of 3,066 accessions of rice germplasm from the National Agrobiodiversity Center, Rural Development Administration, Korea. The rice germplasm accessions have been conserved at a mid-term storage ($4^{\circ}C$, 30% RH) in plastic bottle containing dehydrated (blue) silica-gel and long-term storage ($-18^{\circ}C$, 35% RH) in hermetically sealed metal can on either sides for 25~26.5 years. The final germination percentages of 3,066 rice germplasm accessions of $6.5{\pm}1.0%$ seed moisture content with 94% initial germination stored at $4^{\circ}C$ for 26.5 years declined to 47% while at $-18^{\circ}C$ for 25 years maintained high germinability as 93%. Germination time courses, which represent the average performance of rice ecotypes stored at $4^{\circ}C$ and 30% RH, were fitted regression equation, to calculate the time at which germination characteristically declined to 50% ($P_{50}$). These $P_{50}$ values of Indica, Japonica, Javanica and Tongil type in rice were 39.9, 22.9, 25.4 and 31.8 years, respectively. The rice germplasm stored at $4^{\circ}C$ could be clustered in 4 groups using quartile of final germination after 26.5 years storage. The seed longevity ($P_{50}$) of each group was estimated by regression equation of changed germination percentages according to storage periods. The $P_{50}$ values of group I, group II, group III and group IV were 21.1, 23.6, 30.0 and 75.7 years.