• 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.

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.70-81
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• 2000

DA-5018 is a synthetic capsaicin derivative under development as a non-narcotic a analgesic ag$\varepsilon$nt. DA-50 18 showed a potent analgesic activity against acute and chronic pain m model(Tablel, 2.), but it had a narrow margin of safety. DA-5018 did not bind to opioid(${\kappa}, {\delta}, {\mu}$), NKl, CGRP receptors in vitro and its analgesic effect was not antagonized by naloxone, a and it did not develop analgesic tolerance. In addition DA-5018 had no inhibitory effects against c cyclooxygenase and 5-lipooxygenase activities. DA-5018 significantly increased the relcase of substance P from the slices of the rat spinal cord. These results suggest that DA-50 18 is not a narcotic nor aspirin-like analgesic and the release of substance P is one of analgesic mechanism of action of DA-5018. We found that DA-5018 was almost ten times more potent and was at l least IOO-times less irritable compared to capsaicin. Accordingly development of topical formula was adopted. Topical formula was desiged and screened by flux test of DA-5018 using hairless mouse skin and several formulas were selected. With these topical formulas we a assessed the analgesic efficacy and carried out the toxicity, skin irritation and pharmacokinetic studies. In streptozotocin-induced hyperalgesic rat and 50 % galactose-fed hyperalgesic rat as diabetic pain models, DA-5018 cream increased the pain thresh이ds up to 77.0% and 24.4% respectively, while Zostrix-HP(capsaicin cream) incr$\varepsilon$as cd by 65.9% and 21.0%. DA-5018 c cream showed a good analgesic effect as welI in FCA-induced arthritic rat. DA-5018 cream did not show any toxicological signs in acute and chronic toxicity test and had little skin irritation in car swclIing and scratching t$\varepsilon$st. Pharmacokinetics of DA-50 18 were studied after topical application of ${14}^C$-Iabelled or unlabelIed DA-5018 cream. Plasma and skin concentrations c except applied skin wcre below the dctection limit and after 7-day cummulative application, plasma concentrations were also below detection limit DA-50 18 may have an advantag$\varepsilon$ ov$\varepsilon$r c capsaicin and is now being developed as a topical agent for the treatment of pains. DA-50 18 cream was approved for Korean IND and is now under a Phase II clinical study for arthritic pain a after finising Phase I study. DA-50 18 was also liscensed out to Stiefel Company in America in

• Biomolecules & Therapeutics
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• v.9 no.4
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• pp.291-297
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• 2001

The bioequivalence of two triflusal products was evaluated with 20 healthy volunteers following single oral dose according to the guidelines of Korea Food and Drug Administration (KFDA). Trisa $l^{R}$ capsule (Whanin Pharm. Corp., Korea) and Disgre $n^{R}$ capsule (Myung-In Pharm. Corp., Korea) were used as test product and reference product, respectively. Both products contain 300 mg of trifusal. One capsule of test product or reference product was orally administered to the volunteers, respectively, by randomized two period crossover study (2$\times$2 Latin square method). Blood samples were taken at predetermined time intervals for 4 hours and the determination of trifusal was accomplished using semi-microbore HPLC equipped with automated column switching system. The analytical method with HPLC was validated according to the Bioanalytic Method Validation guideline by F7A prior to determining the plasma samples. The pharmacokinetic parameters (AU $C_{0-4h}$ $C_{max}$ and $T_{max}$) were calculated and ANOVA test was utilized for statistical analysis of parameters. As a result of the assay validation, the limit of quantification of trifusal in human plasma by current assay procedure was 50 ng/ml using 500 $\mu$l of plasma. The accuracy of the assay was from 97.76% to 116.51% while the intra-day and inter-day coefficient of variation of the same concentration range was less than 15%. Average drug concentration at the designated time intervals and pharmacokinetic parameters calculated were not significantly different between two products (p>0.05). The difference of mean AU $C_{olongrightarrow4hr}$, $C_{max}$, and $T_{max}$ between the two products (2.92, 4.39, and -2.44%, respectively) were less than 20%. The power (1-$\beta$) and treatment difference ($\Delta$) for AU $C_{olongrightarrow4hr}$ and $C_{max}$ were more than 0.8 and less than 0.2, respectively. Although the power for $T_{max}$ was under 0.8, $T_{max}$ of the two products was not significantly different from each other (p>0.05). These results satisfied the criteria of KFDA guideline for bioequivalence, indicating the two products of triflusal were bioequivalent.quivalent.ent.ent.

• Journal of Korean society of Dental Hygiene
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• v.13 no.2
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• pp.351-360
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• 2013

Objectives : The purpose of this study was to evaluate the effects of tooth bleaching agent contained 15% carbamide peroxide on the color, microhardness and surface roughness of tooth-colored restorative materials by using pH cycling model. Methods : Four types of tooth-colored restorative materials, including a composite resin(Filtek Z350 ; Z350), a flowable composite resin(Filtek P60 : P60), a compomer(Dyract$^{(R)}$ AP ; DY), and a glass-ionomer cement(KetacTM Molar Easymix ; KM). were used in the study. Eighty-eight specimens of each material were fabricated, randomly divided into two groups(n=44): experimental group(15% carbamide peroxide) and control group(distilled water). These groups were then divided into four subgroups(n=11). All groups were bleached 4 hours per day for 14 days using pH cycling model. The authors measured the color, microhardness, and roughness of the specimens before and after bleaching. The data were analyzed with ANOVA and T-test. Results : Z350 and P60 showed a slight color change(${\Delta}E^*$), whereas DY and KM showed significantly color change(p<0.05). Among them, the greatest color change was observed in DY. Percentage microhardness loss(PML) of the distilled water group was 1.8 to 5.1%, and 15% peroxide peroxide group was 5.0 to 25.2%. Microhardness of DY and KM showed a statistically significant decrease(p<0.05). Roughness was increased in all groups after bleaching. Z350 and P60 does not have a significant difference(p>0.05), however DY and KM significantly increased more than the 0.2 ${\mu}m$(p<0.05). Conclusions : The effects of bleaching on restorative materials were material dependent. It is necessary to consider the type of the material before starting the treatment.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.319-330
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• 1995

The influence of normal late pregnancy on insulin action and insulin secretion was studied in the Sprague-Dawley female rats. On 20th day after mating, intravenous glucose tolerance test(IVGTT) was performed in non pregnant control and pregnant rats. As results of IVGTT, glucose disappearance rate was not significantly different in both groups, but secretory response of insulin was significantly(p<0.05) increased in pregnant rat. And the ratio of insulin/glucose was significantly higher in pregnant rats, which means existence of insulin resistance. These insulin resistance was overcomed by increased secretory response of pancreatic insulin. Insulinogenic index(${\Delta}$ insulin/glucose - 5 min) was highly significantly (r=0.62, p<0.01) correlated with progesterone concentration. Glycogen level and amounts of $^{14}C$-glucose incorporated into glycogen after IVGTT were significantly(p<0.05) decreased in the liver, but were not changed significantly in soleus. Glycogen synthase activity of soleus and liver was not differ significantly in the both groups. Insulin binding at varying concentrations of insulin to crude membrane of pregnant liver was not significantly different from control. In conclusions, although these pregnant rats were normal glucose tolerance due to increased secretory response of insulin, that was correlated with progesterone concentration, pregnant rat had insulin resistance. The mechanisms of insulin resistance were not related to defect of insulin binding phase and glycogen synthase, but suggest pre-receptor and/or postreceptor phase.

• Korean Journal of Materials Research
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• v.29 no.4
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• pp.205-210
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• 2019

$Pb(Zr,Ti)O_3$ (PZT) is used for the various piezoelectric devices owing to its high piezoelectric properties. However, lead (Pb), which is contained in PZT, causes various environment contaminations. $(K,Na)NbO_3$ (NKN) is the most well-known candidate for a lead-free composition to replace PZT. A single crystal has excellent piezoelectric-properties and its properties can be changed by changing the orientation direction. It is hard to fabricate a NKN single crystal due to the sodium and potassium. Thus, $(Na,K)NbO_3-Ba(Cu,Nb)O_3$ (NKN-BCuN) is chosen to fabricate the single crystal with relative ease. NKN-BCuN pellets consist of two parts, yellow single crystals and gray poly-crystals that contain copper. The area that has a large amount of copper particles may melt at low temperature but not the other areas. The liquid phase may be responsible for the abnormal grain growth in NKN-BCuN ceramics. The dielectric constant and tan ${\delta}$ are measured to be 684 and 0.036 at 1 kHz in NKN-BCuN, respectively. The coercive field and remnant polarization are 14 kV/cm and $20{\mu}C/cm^2$.

• Journal of the Korean Geotechnical Society
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• v.25 no.1
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• pp.77-88
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• 2009

Cone factors, $N_{kt}$, $N_{ke}$ and $N_{{\Delta}u}$, for estimating undrained shear strength of Busan clay are evaluated in this study. For this, CPTu and field vane tests are performed for clay layers at two sites, Busan new-port and Noksan, and also $CK_0U$ triaxial tests with undisturbed samples taken from the same site are carried out. From experimental results, it is observed that the undrained shear strengths of clay increases with depth, and the undrained shear strength obtained from triaxial tests is 1.5 times higher than one obtained from vane tests. The normalized undrained shear strengths of Busan clay from triaxial and vane shear tests are $0.26{\sim}0.44$ and $0.20{\sim}0.23$, respectively. In CPTu results, cone tip resistance ($q_c$) and pore pressure ($u_2$) linearly increase with depth, and the pore pressure ratio ($B_q$) of Busan clay is within the range of $0.3{\sim}1.0$. The cone factors, which are determined by comparing the CPTu results with $CK_0U$ triaxial and vane shear test results, are found to be $5{\sim}20$ and $10{\sim}35$, respectively. It is also observed that the cone factors are inversely proportional to the pore pressure ratio. From this, the prediction methods for evaluating the cone factors of Busan clay are developed.

• Food Science and Preservation
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• v.22 no.3
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• pp.392-398
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• 2015

The physicochemical properties of spray-dried rice flour with Lactobacillus plantarum CGKW3 were investigated. Amylose and damaged starch contents of spray-dried rice flour (S10, S20, S30, and S50) with L. plantarum CGKW3 were 14.18~17.75% and 24.65~34.08%, respectively. The particle size of spray-dried rice flour was $82.28{\sim}131.17{\mu}m$. The rice flour with L. plantarum CGKW3 showed a good powder flowability. The water absorption and water solubility of spray-dried rice flour were 1.96~2.13 and 9.91~21.95%, respectively. Thermal properties measured by differential scanning calorimeter revealed that the enthalpy (${\Delta}H$) for starch gelatinization were highest in the rice flour (S50) with L. plantarum CGKW3. When compared, the viable cell number of spray-dried rice flour were found to be in the following order: S10 (5.78 log CFU/g) < S20 (6.38 log CFU/g) < S30 (6.69 log CFU/g) < S50 (7.11 log CFU/g). The survaival rate of L. plantarum CGKW3 was 60.02-73.85%, which reflected the improvement in the quality of rice flour with an increase in treatment concentration. Based on our results, spray-dried rice flour with L. plantarum CGKW3 could be used in various types of rice foods.

• Korean journal of food and cookery science
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• v.21 no.3 s.87
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• pp.301-310
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• 2005

The effects of defatted soy flour on the physicochemical characteristics of dough and bread making properties were studied. Defatted soy flour is added to wheat flour for bread-making in order to maximize the use of isoflavones in the soybean. Different particle sizes of both defatted soy flour and wheat flour were prepared by grinding and sievingwith meshes. In the mixograph test, the addition of defatted soy flour to wheat flour increased the requirement for water and decreased the dough development time. Water absorption rates were also investigated to determine the optimum quantity of water for good dough. As the level of defatted soy flour mixed with wheat flour increased, the sedimentation and P.K. values decreased. In comparison with control, the bread made with defatted soy flour especially had a lower specific loaf volume. Specific loaf volume of wheat flour-defatted soy flour bread prepared (Ed- this is an incomplete sentence, it's only a subject clause, and I don't how what you intend to state). In terms of the staling rate and hardness of the wheat flour-defatted soy flour bread, the increased defatted soy flour had a faster staling rate during storage at 5? than at 25? for 5days. From the result of sensory evaluation, wheat flour-defatted soy flour breads containing up to $4\%$ defatted soy flour were rated as being of high quality.