• Journal of Technologic Dentistry
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• v.23 no.2
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• pp.211-221
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• 2002

The purpose of this study was to analyze the commercial paste opaque products currently available in domestic of foreign as well as domestic, such as Duceram Plus(DU; Ducera Dental GmbH, Germany), VMK 95(VM; Vita Co., Germany), Noritake EX-3(EX; Noritake Co., Japan) and Ceramax(CE; Alphadent Co., Korea). They were characterized in thermal expansion coefficient, particle size distribution, viscosity and solvent using thermomechanical analyzer, particle size analyzer, rheometer and infrared spectrophotometer. Experimental results are as follows; Firstly, thermal expansion coefficients were determined $13.9{\times}10-6/^{\circ}C$ for DU, $14.3{\times}10-6/^{\circ}C$ for VM, $13.3{\times}10-6/^{\circ}C$ for EX, and $14.0{\times}10-6/^{\circ}C$ for CE. Secondly, percent of partice size below $1{\mu}m$ were 12% for DU, VM and CE, and 13% for EX, percent between $1{\mu}m$ and $5{\mu}m$ were 42% for DU, 42% for VM, 38% for EX, and 61 % for CE, percent between $5{\mu}m$ and $10{\mu}m$ were 21 % for DU, 24% for VM, 20% for EX, and 18% for CE, and over $10{\mu}m$ were 25% for DU, 22% for VM, 29% for EX, 9% for CE. Thirdly, the basic composition of the solvent in all of the commercial paste opaques were determined as ethylene glycol from FT-IR investigation. Lastly, measured viscosities were 1798 cp for DU, 536 cp for VM, 1110 cp for EX, and 721 cp for CE.

• Journal of the Korean Magnetics Society
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• v.12 no.2
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• pp.64-67
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• 2002

IrMn pinned spin valve (SV) films with stacks of Ta/NiFe/IrMn/CoFe/Cu/CoFe/NiFe/Ta were prepared by dc sputtering onto thermally oxidized Si (111) substrates at room temperature under a magnetic field of about 100 Oe. The annealing cycle number and temperature dependence of exchange coupling field (H$_{ex}$), magnetoresistance (MR) ratio, and coercivity (H$_{c}$) were investigated. By optimizing the process of deposition and post thermal annealing condition, we obtained the IrMn based SV films with MR ratio of 3.6%, H$_{ex}$ of 1180 Oe for the pinned layer. The H$_{ex}$ is stabilized after the second annealing cycle and it is thought that this SV reveals high thermal stability. The H$_{ex}$ maintained its strength of 600 Oe in operation up to 24$0^{\circ}C$ and decreased monotonically to zero at 27$0^{\circ}C$.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.6
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• pp.63-82
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• 2010

In spite of continuous road construction, traffic congestion has been worsening by radical vehicle's increase and development of surroundings near expressway. Thus, the necessity of traffic management and the needs of provision of traffic information to drivers are raised. In order to solve traffic problems, such as traffic congestion, search for optimal congestion management technique and evaluation of the effect of optimal solution should be examined prior to practice of optimal alternative. However, existing traffic analysis model and simulation programs as tools to search and evaluate optimal alternative are not sufficient to reflect traffic flow characteristics, domestic road and traffic conditions and to link up to Freeway Traffic Management Systems (FTMS). Hence, to use existing traffic analysis and simulation tools are followed by hard work to need a lot of time and cost. Therefore, in this research, Expressway TRaffic Analysis Model (ExTRAM) based on Freeway Traffic Management Systems (FTMS) was developed to apply it into congestion management easily.

• Herbal Formula Science
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• v.17 no.2
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• pp.85-98
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• 2009

The fruits of Schisandra chinensis and Prunus mume have been traditionally used in the Oriental countries as an astringent against diarrhea and abdominal pain, a protectant for liver disease, an antimicrobial, and a blood tonic. However, little is known about the extract of Schizandrae Fructus and Mume Fructus (SMF-Ex) on dextran-sulfate sodium (DSS)-induced colitis in mice. In this study, we investigated the protective effects of SMF-Ex on DSS-induced colitis in mice. An experimental colitis was induced by daily treatment with 5% DSS. SMF-Ex was orally administrated the single dose (80 mg/kg, body weight/day) for 7 days with one time per day. SMF-Ex reduced significantly clinical sign of DSS-induced colitis, including body weight loss, shorten colon length, increased disease activity index (DAI), and histological colon injury. SMF-Ex also inhibited significantly nitric oxide (NO) and prostaglandine $E_2$ ($PGE_2$) productions in DSS-induced colitis mice. Furthermore, SMF-Ex increased significantly an superoxide anion (SOD), catalase, and glutathione peroxidase (Gpx) activity of the colon tissue in DSS-induced colitis mice. These results suggest that SMF-Ex administration could reduce significantly the clinical signs and inflammatory mediators, and increase antioxidant activity in DSS-induced colitis model mice and is a good candidate for further evaluation as an effective anti-ulcerative agent.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.236-246
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• 2010

The 3-Acetylpyridine(3-AP) induces cerebellar injury which is chemoablation of the inferior olive nucleus. The purpose of this study was to investigate the effects of exercise(Ex) and electroacupuncture(EA) on muscle activity of hindlimb and serum brain derived neurotrophic factor(BDNF) in the ataxia rats by the 3-AP. 12-week-aged male Sprague-Dawley rats were randomly divided into the 5 groups: Control, 3-AP, 3-AP+Ex, 3-AP+EA and 3-AP+Ex+EA groups. Maximal Height Vertical Jump(MHVJ) was significantly decreased in the 3-AP compared with control group, and it was increased in Ex, EA and Ex+EA groups than 3-AP group. The muscle activity of hindlimb was significantly increased in the 3-AP groups than control group, also it was most decreased in Ex+EA group. The concentration of BDNF of the serum was significantly decreased in the Ex, EA and Ex+EA groups than 3-AP group. The results of this study showed that dynamic exercise and electroacupuncture have a positive effect on functional recovery and in the ataxia rats by the 3-AP.

• Science of Emotion and Sensibility
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• v.17 no.2
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• pp.63-76
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• 2014

Although most behavioral reaction times (RTs) for cognitive tasks exhibit positively skewed distributions, the majority of studies primarily rely on a measure of central tendency (e.g. mean) which can cause misinterpretations of data's underlying property. The purpose of current study is to introduce procedures for describing characteristics of RT distributions, thereby effectively examine the influence of experimental manipulations. On the basis of assumption that RT distribution can be represented as a convolution of Gaussian and exponential variables, we fitted the ex-Gaussian function under a maximum-likelihood method. The ex-Gaussian function provides quantitative parameters of distributional properties and the probability density functions. Here we exemplified distributional analysis by using empirical RT data from two conventional visual search tasks, and attempted theoretical interpretation for setsize effect leading proportional mean RT delays. We believe that distributional RT analysis with a mathematical function beyond the central tendency estimates could provide insights into various theoretical and individual difference studies.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.371-372
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• 2012

We have studied lead-based gapless semiconductors, $PbPdO_2$, which is very sensitive to external parameters such as temperature, pressure, electric field, etc[1]. We have fabricated pure $PbPdO_2$, Co- and Mn-doped $PbPdO_2$ thin films using the pulsed laser deposition. Because of the volatile element of Pb, it is very difficult to grow the films. Note that in case of $MgB_2$, Mg is also volatile element. So in order to enhance the quality of $MgB_2$, some experiments are carried out in annealing with Mg-rich atmosphere [2]. This annealing process with volatile element plays an important role in making smooth surface. Thus, we applied such process to our studies of $PbPdO_2$ thin films. As a result, we found the optimal condition of ex-situ annealing temperature ${\sim}650^{\circ}C$ and time ~12 hrs. The ex-situ annealing brought the extreme change of surface morphology of thin films. After ex-situ annealing with PbO-rich atmosphere, the grain size of thin film was almost 100 times enlarged for all the thin films and also the PbO impurity phase was smeared out. And from X-ray diffraction measurements, we determined highly crystallized phases after annealing. So, we measured electrical and magnetic properties. Because of reduced grain boundary, the resistivity of ex-situ annealed samples changed smaller than no ex-situ sample. And the carrier densities of thin films were decreased with ex-situ annealing time. In this case, oxygen vacancies were removed by ex-situ annealing. Furthermore, we will discuss the transport and magnetic properties in pure $PbPdO_2$, Co- and Mn-doped $PbPdO_2$ thin films in detail.

• Journal of Community Nutrition
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• v.1 no.2
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• pp.125-132
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• 1999

This study investigated the differences in dietary intake, age, body mass index(BMI), marital status and education of 1,585 Korean healthy males among current smokers, ex-smokers and non-smokers. Dietary intake was determined by a food frequency questionnaire at the Samsung Medical Center in Seoul, Korea. A bioelectric impedance analyzer measured height, body weight and BMI. This study identified 50% of the study group as current smokers and 30% as ex-smokers and 20% as non-smokers. The mean body mass index was 23.7kg/㎡ and did not differ significantly among the three groups. THe current smokers were younger(44.9 years old) and contained a lower percentage(58.5%) of college graduate than that of ex-smokers or non-smokers. The percentage of non-consumers of meat, eggs, beans and bean products was higher in non-smokers than that of ex-smokers or current smokers. Smoking was to a significant degree positively related to the amount of coffee and alcoholic beverages consumed and negatively related to the amount of milk and milk products and fruits consumed. The intake of eggs, milk and milk products, fruit, coffee, sweets, fats and oils were significantly different among the three groups. after adjusting for age, education level, marital status, and alcohol consumption. There was a strong positive relationship between smoking intensity and the intake of coffee and alcoholic beverages(p<0.0005), and an inverse relationship between smoking intensity and fruit, milk and milk product intake(p<0.005). The current smokers were characterized by a higher intake of total energy and cholesterol, and a lower intake of dietary fibers, ${\beta}$-carotine and folate than those of non-smokers or ex-smokers. The nutrient intake of ex-smokers was moderate and highest in ${\beta}$-carotine and folate, which suggested that ex-smokers were trying to change their life style.

• KSBB Journal
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• v.18 no.1
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• pp.25-29
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• 2003

In this study, we examined the effects of the methanolic extract(CL-ex) of Codonopsis lanceolata on the angiogenesis stimulated with basic fibroblast growth factor(bFGF) in vitro, using porcine pulmonary arterial endothelial cells(PPAECs). In addition, we investigated the endothelial functions involved in angiogenesis, such as proliferation, migration and secretion of matrix metalloproteinases(MMPs), using human umbilical vein endothelial cells(HUVECS). CL-ex inhibited FGF-induced sprout formation in vitro at concentrations of 0.1-100 ug/ml. Although CL-ex did not affect the proliferation of endothelial cells, CL-ex strongly inhibited the FGF-induced migration of HUVECS at concentrations of 0.1-1 ug/ml; the degree of inhibition of endothelial cells by C-ex was 49.4% at 0.1 ug/ml and 71.9 % at 1.0 ug/ml. Moreover, CL-ex inhibited the secretion of MMPs from HUVECS stimulated with FGF. Therefore, the inhibitory effect of CL-ex on angiogenesis in vitro could be explained by the inhibition of endothelial cell migration. From these results, we suggest that Codonopsis lanceolata is a useful herb for the development of therapeutics or preventive food factors for angiogenesis related diseases, such as tumors.

• YAKHAK HOEJI
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• v.58 no.5
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• pp.343-348
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• 2014

In the present studies, we examined effect of chamomile flowers extract (CH-Ex), which has traditionally been used as antiphlogistics in Europe for many centuries, against Candida albicans-caused septic arthritis. Candida albicans is a major etiological agent among fungal septic arthritis. This effect was investigated in a murine model of the septic arthritis. That is, mice that were given an emulsion form of C. albicans cell wall (CACW) via footpad route were treated intraperitoneally with the CH-Ex for 3 times every 3 days. Degrees of the footpad-swellings were measured with dial gauger. Data showed that the CH-Ex resulted in the reduction of swelling. For instance, at Day 9 when swelling reached the highest peak, there was up to app. 60% reduction of edema in mice injected with the CH-Ex, compared to that of the control mice that received no treatment (P<0.05). This therapeutic anti-arthritic activity appeared to be mediated by inhibitions of NO (nitric oxide) production from activated RAW264.7 macrophages and proliferation of Con A-treated T lymphocytes. Analysis by HPLC revealed that the CH-Ex contained eight polyphenolic compounds including chlorogenic acid (CRA) and rutin. We have reported the CRA and rutin respectively have the anti-arthritic activity. This correlation implicates that CRA and rutin in the CH-Ex may be responsible for the activity. Combined all together, the CH-Ex has anti-arthritic activity against C. albicans-caused septic arthritis, possibly by inhibiting NO production and proliferation of T cells. This activity seems to be contributed by, at least, CRA and rutin among the compounds in the CH-Ex.