• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.109-120
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• 2004

INTRODUCTION: The build-up method has been used for application of porcelain powder on the metal framework to make final tooth shape conventionally. This method takes time and need skill to mimic final shade and shape of porcelain fused to metal crown. The purpose of this study was to develop standard shape and shade laminating porcelain forms to reduce build-up time. METHODS: To make tooth form porcelain paste, several liquid organic compounds were added to conventional feldspathic porcelain. The amount of additives and rheologic property were tested to find out best composition. Comparison of mixing methods to reduced porosity, proper heating schedule, and measurement of shrinkage amount and residual organic materials were performed to set-up standard procedures. Finally, biaxial flexural strength and color of preformed laminated paste porcelain were compared with those of porcelain which fabricated by the conventional build-up method. RESULTS: There was no significant difference in physical properties and color stability between two fabrication methods after various testing methods. Conclusion: This new build-up method can be applied to fabricate the PFM crown and bridge without any loss of strength and optical properties.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.12
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• pp.1682-1688
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• 2007

The effects of cultivar and DAPs on the lignin content and dyeability of the kenaf fibers were investigated. Four kenaf fiber samples were prepared from two cultivars, Tainung 2 and Everglades 41, and their 60 and 120 DAPs(days after planting) for the experiments. The lignin contents of the kenaf fibers of Tainung 2(T2) and Everglades 41(E41) were $11.29{\sim}12.78%$. Both T2 and E41 kenaf fibers had comparable amount of lignin, and klason lignin of the fibers was $2.5{\sim}3$ times as much as much as acid-soluble lignin. In both T2 and E41, 120 DAPs kenaf have 1% more lignin than 60 DAPs kenaf. The moisture regains of the four kenaf fiber samples were almost the same as $10.25{\pm}0.05%$. The absorbances of residual solution after dyeing for $1{\sim}180$ minutes with Red 81 at maximum wavelength 520 nm and Green 26 at 600 nm were measured. Comparing to Green 26, the dyeing rate of Red 81 was rapid and equilibrium state was reached in 12 minutes. The CIE $L^*,\;a^*, \;b^*,\;{\Delta}E$ and K/S values of the kenaf fibers dyed with Red 81 and Green 26 were measured as well. The dye exhaustion ratio of 60 DAPs kenaf was higher than that of 120 DAP.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.449-455
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• 2005

To reduce saft content of kochujang, various combinations of sub-materials such as ethanol mustard and chitosan were added to kochujang, and their effects on microbial characteristics, enzyme activities, and physicochemical characteristics of kochujang were investigated after 12 weeks of fermentation. Activities of ${\beta}$-amylase and pretense were low in ethanol-mustard-chitosan-added kochujang, whereas no significant difference was observed in ${\alpha$-amylase activity among all groups. Number of viable yeast cells decreased remarkably in mustard-added kochujang during late aging period, and anaerobic bacterial counts decreased in sub-material-added groups. Consistency of kochujang increased by addition of sub-materials, and oxidation-reduction potential was low in chitosan-added group. Mustard-chitosan-added kochujang showed lowest increase in total color difference(${\Dalta}E$) and decrease in water activity. PH of kochujang wns highest in mustard-chitosan-added kochujang, resulting in significantly increased titratable acidity. Addition of sub-material increased reducing sugar contents of kochujang, whereas ethanol production was significantly repressed in mustard-chitosan-added kochujang. Amino nitrogen content was Highest in mustard-chitosan-added kochujang during late aging period, whereas ammonia nitrogen content was lower in ethanol-mustard-added kochujang. Results of sensory evaluation indicated ethanol-mustard-added kochujang was more acceptable than other groups in taste and overall acceptability.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.196-205
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• 1999

Kochujang prepared by liquid and solid koji using isolated bacteria(Sunchang 1 and Park 2) showing excellent enzyme activities were gamma irradiated at $15{\pm}1.5\;kGy$ to investigate their qualities from the physicochemical, microbiological and enzymatic points of view during fermentaion at $25^{\circ}C$ for 90 days. The amino type nitrogen contents were $0.6{\sim}0.7%$ after 30 days of fermentation. Irradiation completly stopped gas production which is one of biggest problem of kochujang distribution. Enzyme activities were some different according to koji and irradiation treatment. Amino type nitrogen content as one the most important quality indice was higher in kochujang fermented by isolated bacteria (Park 2) than non inoculated traditional kochujang. But sensory quality was not significantly different.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.3
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• pp.187-190
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• 2006

In order to produce hemp with low cannabinoids and appropriate fiber yield, seeds of the IH3 (non drug type germplasm) and local variety (drug type cultivar) were mixed to 1:1, 2:1, 3:1 on base of seed weight ratio and cultivated for seed production. In the seed yield trial, the weight of 1000 grains were around 21 g, which was increased in proportion to the ratio of IH3 seeds but seed yield were 100 kg/10a, which were not significantly different by the seeds-mixing ratio. In fiber yield trials with seeds from seed yield trial, fiber yield ranged $193{\sim}198kg/10a$ which was not significantly different by the seeds mixing ratio but the content of THC(${\Delta}$-9-tetrahydrocannabinol) was lowered in proportion to the ratio of IH3 seeds. Variation of THC and CBD (Cannabidiol) level in the 150 plant cultivated with various seed mixing ratio reflected that the percentage of drug and intermediate type were decreased but non drug type were increased in proportion to the ratio of IH3 seeds.

• Journal of Pharmaceutical Investigation
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• v.32 no.2
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• pp.119-125
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• 2002

A rapid, selective and reproducible high-performance liquid chromatographic method has been developed for the determination of terazocin in human plasma. Terazocin plus the internal standard, prazocin hydrochloride, were extracted from alkalified plasma with tert-butylmethyl ether, back-extracted into 0.05% phosphoric acid. Fifty ${\mu}l-portions$ of extract were injected onto a octadecylsilane column and eluted with a mixture of acetonitrile, water and triethylamine (30 : 70 : 0.1 v/v, adjusted to pH 5.0 with dilute phosphoric acid) at a flow rate of 1.0 ml/min. The fluorescence intensity of column eluents was monitored at excitation wavelength of 250 nm and emission wavelength of 370 nm. No interference peaks were observed. The practical limit of quantitation was 5 ng/ml for terazocin. The average intraday and interday coefficients of variation were 4.15 and 3.54%, respectively. Also intraday and interday precisions over the range $5{\sim}60\;ng/ml$ were $0.49{\sim}2.92\;and\;0.38{\sim}5.12%$, respectively. The bioequivalence of two terazosin tablets, the $Hytrine^{\circledR}$ (Il Yang Pharmaceutical Co., Ltd.) and the $Teratonin^{\circledR}$ (Sam-A Pharmaceutical Co., Ltd.), was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). Sixteen healthy male volunteers $(24.6{\pm}2.0\;years\;old)$ were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 2 mg of terazosin was orally administered, blood was taken at predetermined time intervals and the concentration of terazosin in plasma was determined with a HPLC method using spectrofluorometric detector. AUC was calculated by the linear trapezoidal method. $C_{max}\;and\;T_{max}$ were compiled from the plasma drug concentration-time data. Analysis of variance (ANOVA) was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_t,\;C_{max}\;and\;T_{max}$ between the two preparations were 0.21 %, 5.53% and 8.82%, respectively. The powers $(1-{\beta})\;for\;AUC_t,\;C_{max}\;and\;T_{max}$ were >99%, 97.49%, and 33.26%, respectively. Minimum detectable differences $({\Delta},\;%)\;at\;{\alpha}=0.1\;and\;1-{\beta}=0.8$ and the 90% confidence intervals were all less than ${\pm}20%$ except for $T_{max}.\;AUC_t\;and\;C_{max}$ met the criteria of KDFA for bioequivalence, indicating that $Teratonin^{circledR}$ tablets are bioequivalent to $Hytrine^{circledR}$ tablets.

• Food Science and Preservation
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• v.19 no.1
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• pp.67-73
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• 2012

This study was carried out to investigate the packaging status of the $Agaricus$ $bisporus$ mushrooms and the benefits of storing them after precooling to improve their distribution system using small packages. The packaging status of the $Agaricus$ $bisporus$ mushrooms was surveyed at a farm, a department store, a wholesale market, and a supermarket from May to September 2011. The packaging materials that were used were PS, carton, PP, LDPE, PLA, and PVC. The harvested $Agaricus$ $bisporus$ mushrooms were precooled at $4^{\circ}C$ for three hours and were then stored at $20^{\circ}C$ for three days. The weight loss rate of the precooled sample was slightly lower than that of the unprecooled sample; conversely, the L value of the precooled sample was higher than that of the unprecooled sample. The ${\Delta}E$ value was lowest in the precooled sample after packaging. The precooling process effectively prolonged the shelf life and enhanced the quality of the$Agaricus$ $bisporus$ mushrooms.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.211-220
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• 1998

The stochiometric composition of $AgGaS_2$polycrystal source materials for the single crystal thin films were prepared from horizontal furnace. From the extrapolation method of X-ray diffraction patterns, it was found that the polycrystal $AgGaS_2$has tetragonal structure of which lattice constant $a_0\;and \;c_0$ were 5.756 $\AA$ and 10.305 $\AA$, respectively. $AgGaS_2$single crystal thin film was deposited on throughly etched GaAs(100) substrate from mixed crystal $AgGaS_2$by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were $590^{\circ}C$ and $440^{\circ}C$ respectively, and the growth rate of the single crystal thin films was about 0.5 $mu \textrm{m}$/h. The crystallinity of the grown single crystal thin films was investigated by the DCRC (double crystal X-ray diffraction rocking curve). The optical energy gaps were found to be 2.61 eV for $AgGaS_2$single crystal thin films at room temperature. The temperature dependence of the photocurrent peak energy is well explained by the Varshni equation, then the constants in the Varshni equation are given by${\Alpha};=;8.695{\times}10^{-4};eV/K,and;{\beta};=;332;K$. from the photocurrent spectra by illumination of polarized light of the $AgGaS_2$single crystal thin film, we have found that crystal field splitting $\Delta$Cr was 0.28 eV at 20 K. From the PL spectra at 20 K, the peaks corresponding to free and bound excitons and a broad emission band due to D-A pairs are identified. The binding energy of the free excitons are determined to be 0.2676 eV and 0.2430 eV and the dissociation energy of the bound excitons to be 0.4695 eV.

• Journal of dental hygiene science
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• v.14 no.2
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• pp.191-197
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• 2014

The purpose of this study was to evaluate the tooth whitening efficacy of 2.9% hydrogen peroxide strip with primer gel of alkaline condition and containing metallic salts as catalyst in-vitro. Hydroxyapatite (HAP) disk was made by compressing and sintering 0.3 g of mixture of HAP powder and polyvinyl alcohol. This HAP disk was stained using modified Stookey's methods. Main bleaching materials were 2.9% hydrogen peroxide strips and the primer gel containing metallic salts as catalyst and pH controller. Stained HAP disks were allocated to each control or experimental groups by color grade. Stained HAP disks were treated for 30 minutes in $37^{\circ}C/80%$ incubator for wetting, then each primer gel according to control or each test group was spread and strips were attached. After 30 minutes for each group strips were detached and HAP disks were washed, dried then color was measured by colorimeter. Efficacy was evaluated by comparing ${\Delta}L$ values of HAP disks at baseline and after treated. Among some kinds of metallic salts for as catalyst, ferric chloride showed best improvement of efficacy and it was statistically significant (p<0.05) compared to control group. Evaluating whitening efficacy according to various pH of primer, efficacy using primer of alkaline condition was increased significantly (p<0.05) compared to control and primers of acidic or neutral conditions. Evaluating whitening efficacy for time course, efficacy of test group for 30 minutes was similar to that of control for 120 minutes. It can be concluded that 2.9% hydrogen peroxide strips using with primer of alkaline condition and containing ferric chloride showed significantly increased whitening efficacy compared to the case of strips only.

• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.311-315
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• 2004

The brown planthopper, Nilaparvata lugens, is among the most serious insect pests of rice. It is widely distributed in Asia, Australia and Pacific islands. An earlier mitochondrial DNA study revealed that there exist significant genetic differences between populations north and south of the Red River Delta region in Vietnam. However the mitochondrial DNA was not sufficiently variable to examine the sources of immigration. For a more detailed analysis of geographic population structure of N. lugens, we developed microsatellite markers. Thirty-seven putative microsatellite loci were isolated using a magnetic biotin method, and five primer pairs designed from the flanking regions of sequenced microsatellite clones were labeled with fluorescent. Of these five primer sets, two have proven to be useful across all the samples we used in this study. We used variation at these two microsatellite loci to test the hypothesis that N. lugens biotypes (1, 2, and 3) sampled from laboratory selection constituted distinct genetic units. Allele frequency differences among the three major biotype categories were not significantly different at one locus (27035). However, the other (7314) did show differences among the major three biotypes. The methods we describe here will be useful for studying population structure of crop pest and for tracking the patterns of migratory pest like the rice planthoppers.