• Journal of Technologic Dentistry
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• v.30 no.1
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• pp.17-23
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• 2008

Gypsum products are used for the preparation of stone casts of oral and maxillofacial structures and as important adjuncts to dental laboratory operations involved in the production of dental prosthesis. Accuracy and dimensional stability over time are properties of concern in fixed prothodontics. Gypsum products used in denstry are a form calcium sulfate hemihydrate and are classified as 1 of 5 types according to International Standard Organization(ISO) 6873. All die materials exhibit some dimensional change during setting, but expansion and contraction during setting and dimensional changes in response to varations in temperature and the water-powder ratio must be minimal. Although numerous investigators have studied the properties of die materials, several products have been introduced recently with manufacturer claims of superior dimensional stalility. The aim of this study was to determine the surface properties using various separating materials of dental gypsum products The results were as follows 1. In the comparison of first and second plaster distances before separation in different separating agent, there was no significant difference except using Trio separating agent. The interface using Trio separating agent forms like to pores. 2. In the comparison of first and second plaster distances after separation in different separating agent, there was significant difference. The interface of plasters using WD-40, Trio and Vaseline was showed some gaps. Each they were measured at average 7.97 $\pm$ 2.07 ${\mu}m$, 63.09 $\pm$ 23.25 ${\mu}m$, 27.59 $\pm$ 4.19 ${\mu}m$. 3. In the comparison of the surface, the surface of control sample(using none seperating agent) showed irregular properties and the surface using Trio and Vaseline become wrinkled. Specially the surface using Vaseline was showed shiny properties. But the surface using MAGIC SEP, Plaster seperating agent, WD-40 showed regular properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1034-1043
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• 1999

Rheological properties of dough made from waxy barley(Iri28) flour wheat flour mixtures with additives were investigated for the preparation of waxy barley bread using farinograph, extensograph and amy lograph. The water absorption, development time and dough weakness increased as the waxy barley flour level increased in all blends; however, dough stability decreased. Farinogram properties of 10% waxy barley flour added mixture were similar to those of 100% wheat flour. The addition of A.A(ascorbic acid), gluten, HPMC(hydroxy propyl methyl cellulose) improved rheological properties of dough with 30% waxy barley flour added mixture. In particular, stability and weakness of the dough showed greater dough improving effect by addition of A.A. For the extensograph data, strength, resistance and extensibility of dough decreased with increasing level of waxy barley flour. With the addition of additives, extensogram properties were variable for 30% waxy barley flour mixture. Of these additives, gluten had highest value in strength of dough. Addition of A.A and HPMC to 30% waxy barley flour added mixture resulted in an increase in the resistance and a decrease in the extensibility. Waxy barley flour added mixtures showed little higher gelatinization temperature on amylograph data than control. Maximum viscosity reduced as the waxy barley flour level increased. Also 30% waxy barley flour added mixture containing A.A and HPMC showed a decrease in maximum viscosity. But addition of gluten to 30% waxy barley flour mixture resulted an increase in the maximum viscosity. All of 30% waxy barley flour added mixture with additives had lower gelatinization temperature than those without additives. In the SEM images, starch granules were dispersed in a protein matrix. A non continuous, loose protein starch matrix was observed in all waxy barley flour mixture by SEM. Addition of additives gave the dough a more continuous structure with interactions between the starch granule and protein component.

• Preventive Nutrition and Food Science
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• v.11 no.1
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• pp.54-60
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• 2006

The immunomodulatory effect of a new herbal preparation, HemoHIM, on the recovery from leukopenia induced by cyclophosphamide treatment was investigated. The HemoHIM was made up with an addition of the ethanol-insoluble fraction to the total water extract of Angelica Radix, Cnidii Rhizoma and Paeonia Radix. Daily oral administration of 100 mg/kg BW or 500 mg/kg BW HemoHIM accelerated the recovery from cyclophosphamide-induced leukopenia. HemoHIM increased the number of leukocytes and lymphocytes in the peripheral blood when compared with the cyclophosphamide-treated control. Moreover, the suppressed natural killer (NK) cell activity and interferon $(IFN)-{\gamma}$ secretion in the cyclophosphamide-treated mice were restored by the administration of HemoHIM. HemoHIM significantly reduced the abnormally heightened ratio of interleukin $(IL)-4/IFN-{\gamma}$ and immunoglobulin (Ig)E/IgG2a in the cyclophosphamide-treated mice. These results suggest that HemoHIM accelerates the recovery from leukopenia and alleviates the imbalanced T helper (Th)l/Th2 responses in the cyclophosphamide-treated mice. Additionally, HemoHIM was found to stimulate normal splenocytes to secrete not only Thl type cytokines such as $IFN-{\gamma}$ and IL-2, but also Th2 type cytokine IL-4. In conclusion, our results show that HemoHIM certainly has an influence on the balanced recovery of immune cells and the activation of their activities in the cyclophosphamide-treated mice.

• Journal of Acupuncture Research
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• v.23 no.6
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• pp.199-205
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• 2006

Objectives : The present study was conducted to evaluate the analgesic effects of automatically controlled heating acupuncture(ACHA) using 2 different pain models(acute pain and neuropathic pain) and 2 different stimulation conditions (heating $41.5^{\cdot}C$ and heating $44.5^{\cdot}C$) in Sprague-Dawley rats. Methods : Tail flick latency(TFL) to a noxious radiant heat stimulus in lightly anesthetized rats was measured before and after ACHA stimulation for 5-min at the Zusanli(ST36) acupoint. For the neuropathic surgery, the right superior caudal trunk was resected at the level between S1 and S2 spinal nerves innervating the tail. Two weeks after the nerve injury, ACHA stimulation($41.5^{\cdot}C$ or $44.5^{\cdot}C$) was delivered to Zusanli(ST36) for 5 min. The behavioral signs of warm allodynia were evaluated by the tail immersion test (i.e. immersing the tail in warm $water(40^{\cdot}C)$ and measuring the latency to an abrupt tail movement) before and after the ACHA stimulation. Results : In the TFL test, ACHA stimulations under both the conditions above produced more potent analgesic effects than plain acupuncture(PA, acupuncture needle insertion only) and control(no treatment). In the tail immersion test, ACHA stimulations under all of the conditions had markedly relieved the warm allodynia signs. Conclusion : Automatically controlled heating acupul1cture produced analgesic effecs in acute and neuropathic pains.

• Journal of Acupuncture Research
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• v.37 no.2
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• pp.110-117
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• 2020

Background: The aim of this pilot study was to assess the safety and dosing of scolopendrid pharmacopuncture (SPP). Methods: A total of 40 healthy Sprague-Dawley rats (males and 20 females 20) were selected following a 7-day inspection and acclimation period. SPP was administered via intramuscular injection, over a 2-week period using 3 doses including a high-dose [0.84 mg of scolopendrid per kg of body weight (BW)], a med-dose (0.42 mg/kg BW), and a low-dose (0.21 mg/kg BW). The control group was injected with sterile water into the muscles. Unusual changes caused by administration of the test substance were observed. Weight, feed intake, organ weight, and hematological examinations were compared among the groups. Using the SPSS statistical program, Levene's test was performed to evaluate the homogeneity of variances, and a one-way ANOVA test was subsequently performed to assess the significance between each test group. Results: During the experiment no animals died. Weight change, food consumption, organ weight, hematological test, and blood biochemical tests showed no significant differences in the treatment groups compared to controls. Conclusion: No toxicological changes related to the administration of test substances were observed. Therefore, the LD₅₀ (lethal-dose that kills 50%) of scolopendrid pharmacoupuncture in rats was greater than 0.84 mg/kg.

• The korean journal of orthodontics
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• v.24 no.4 s.47
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• pp.957-967
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• 1994

The purpose of this study was to evaluate the effects of different bases of ceramic brackets on shear bond strength and to observe failure patterns of bracket bondings. Lower bicuspid brackets whose bases designed for the macromechanical and silane treated chemical bonding those for silane treated chemical bonding, those for micromechanical bonding, and those for macromechanical bonding were tested as experimental groups, and foil mesh-backed metal brackets as a control group. All the brackets were bonded with $Mono-Lok\;2^{(TM)}$ on the labial surface of extracted human lower bicuspids after etching the enamel with $38\%$ phosphoric acid solution for 60 seconds. The shear bond strengths were measured on the universal test machine after 24 hours passed in the $37^{\circ}C$ water bath. The gathered data were evaluated and tested by ANOVA and Duncan's multiple range test, and those results were as follows. The shear bond strengths of brackets for macromechanical and chemical bonding, those for chemical bonding, and those for micromechanical bonding were not different (p>0.05), but showed statistically higher than those of metal bracket and those of ceramic bracket for micromechanical bonding(p<0.05). The shear bond strengths of ceramic bracket for micromechanical bonding showed statistically lower than those of metal bracket(p<0.05). The enamel fractures and/or ceramic bracket fractures were observed in the cases of higher bond strength than that of metal bracket. These results supported that silane treated base of ceramic bracket show higher shear bond strength than that of metal bracket, and suggested that micromechanical form of ceramic bracket bases show higher shear bond strength than that of macromechanical form.

• Journal of Hydrogen and New Energy
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• v.23 no.6
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• pp.670-677
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• 2012

Perovskite-type oxides such as doped barium zirconate ($BaZrO_3$) show high proton conductivity and chemical stability when they are exposed to hydrogen and water vapour containing atmospheres, thus it can be applicable to the hydrogen separation and the fuel cell electrolyte membranes. However the high temperature ($1700-1800^{\circ}C$) and long sintering times (24h) are generally required to prepare the fully densified $BaZrO_3$ pellets. These sintering conditions lead to the limitation of the grain size growth and the degradation of conductivity due to the acceleration of BaO evaporation at $1200^{\circ}C$. Here we demonstrate NiO-doped $BaZr_{0.85}Y_{0.15}O_{3-{\delta}}$ with lower calcination and sintering temperature, less experimental procedure and lower process cost than the conventional mixing method. The stoichiometry of $BaZr_{0.85}Y_{0.15}O_{3-{\delta}}$ was optimized by the control of excess amount of Ba (5mol%) to minimized BaO evaporation. We found that the crystal size of NiO-doped $BaZr_{0.85}Y_{0.15}O_{3-{\delta}}$ was increased with increase of calcination temperature from XRD analysis. NiO-doped $BaZr_{0.85}Y_{0.15}O_{3-{\delta}}$ powder was calcined at $1000^{\circ}C$ for 12h when its showed the highest conductivity of $3.3{\times}10^{-2}s/cm$.

• Journal of Hydrogen and New Energy
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• v.29 no.1
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• pp.11-18
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• 2018

A high efficiency integrated reforming system for improving the efficiency of the 5 kW PEMFC system used as the back up power of building was studied. The separated reforming system consisted of three parts - A steam reformer with two stage concentric circular shape, a heat exchanger type steam generator and a CO shift reactor. Temperature and steam carbon ratio (SCR) were control variables during operation. The operating conditions were optimized based on the thermal efficiency of the steam reformer as reformate gas composition changes at different temperature. In experiments, water was fully vaporized in the steam generator up to SCR 3.5 and the maximum thermal efficiency was achieved at the operating temperature around $700^{\circ}C$ in the steam reforming reactor. With the results of the separated reforming system research, we improved the shape of high efficiency integrated reformer. The performance evaluation of the integrated reformer was based on optimized operating conditions in SCR 3.5. As a result, the developed integrated reforming system maintained an efficiency of 76% and constant performance over 3,000 hours.

• KSBB Journal
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• v.16 no.6
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• pp.547-553
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• 2001

Glycoprotein from the water extract of dried root barks of slippery Elm was investigated for its anticancer immunostimulating activity, The glycoprotein contained molecular weight 15,000 to 500,000 Da, total carbohydrates 55.8 to 72.1%), total uronic acid 30.0 to 30.5%, and total proteins 5.0 to 6.1%. The anticancer immunostimulating activities were examined for both in vitro bioassays such as immune cell proliferation assay, mixed lymphocyte reaction (MLR), direct mitogenicity, T-dependent antibody production, and in vivo bioassays such as septic shock test and anticancer activity test in B16 melanoma transplanted mouse model. In vivo assay, the glycoprotein at the concentration of 3 mg/kg showed the best result that median survival time increased to about 140% in contrast to control groups.

• KSBB Journal
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• v.24 no.1
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• pp.25-29
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• 2009

Ceramide is important not only for the maintenance of the barrier function of the skin but also for the water-binding capacity of the stratum corneum. Though the effectiveness of ceramide is not understood fully, ceramide has become a widely used ingredient in cosmetic and pharmaceutical industries. However, ceramide production from Saccharomyces cerevisiae has not been widely studied and the quantity are very low. Gene deletion in the cell is used frequently to investigate the function of gene and verification research of drug target. Specially, deletion mutant library is useful for a large amount functional analysis of gene. In this study, deletion mutants of genes on the metabolic pathway of ceramide synthesis in S. cerevisiae were grown in a batch culture and the cellular content of ceramide was measured. The ceramide content was highest in ${\triangle}$ydc1 mutant and 6 mg ceramide/g cell was obtained.