• Transactions of the Korean hydrogen and new energy society
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• v.22 no.5
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• pp.649-655
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• 2011

Methane direct cracking can be utilized to produce $CO_x$ and $NO_x$-free hydrogen for PEM fuel cells, oil refineries, ammonia and methanol production. We present the results of a systematic study of methane direct cracking using a mixed conducting oxide, Y-doped $BaZrO_3$ ($BaZr_{0.85}Y_{0.15}O_3$), membrane. In this paper, dense $BaZr_{0.85}Y_{0.15}O_3$ membrane with disk shape was successfully sintered at $1400^{\circ}C$ with a relative density of more 93% via addition of 1 wt% ZnO. The ($BaZr_{0.85}Y_{0.15}O_3$) membrane is covered with Pd as catalyst for methane decomposition with an DC magnetron sputtering method. Reaction temperature was $800^{\circ}C$ and high purity methane as reactant was employed to membrane side with 1.5 bar pressure. The $H_2$ produced by the reaction was transported through mixed conducting oxide membrane to the outer side. In addition, it was observed that the carbon, by-product, after methane direct cracking was deposited on the Pd/ZnO-$BaZr_{0.85}Y_{0.15}O_3$ membrane. The produced carbon has a shape of sphere and nanosheet, and a particle size of 80 to 100 nm.

• Research in Vestibular Science
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• v.17 no.4
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• pp.152-159
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• 2018

Objectives: The Korean Dizziness Handicap Inventory (KDHI), which includes 25 patient-reported items, has been used to assess self-reported dizziness in Korean patients with Parkinson disease (PD). Nevertheless, few studies have examined the KDHI based on item-response theory within this population. The aim of our study was to address the feasibility and clinimetric properties of the KDHI instrument using polytomous Rasch measurement analysis. Methods: The unidimensionality, scale targeting, separation reliability, item difficulty (severity), and response category utility of the KDHI were statistically assessed based on the Andrich rating scale model. The utilities of the orderedresponse categories of the 3-point Likert scale were analyzed with reference to the probability curves of the response categories. The separation reliability of the KDHI was assessed based on person separation reliability (PSR), which is used to measure the capacity to discriminate among groups of patients with different levels of balance deficits. Results: Principal component analyses of residuals revealed that the KDHI had unidimensionality. The KHDI had satisfactory PSR and there were no disordered thresholds in the 3-point rating scale. However, the KDHI showed several issues for inappropriate scale targeting and misfit items (items 1 and 2) for Rasch model. Conclusions: The KDHI provide unidimensional measures of imbalance symptoms in patients with PD with adequate separation reliability. There was no statistical evidence of disorder in polytomous rating scales. The Rasch analysis results suggest that the KDHI is a reliable scale for measuring the imbalance symptoms in PD patients, and identified parts for possible amendments in order to further improve the linear metric scale.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.416-425
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• 2009

Angiogenesis is important for promoting cardiovascular disease, wound healing, and tissue regeneration. We here investigated the pharmacological effects of Korea red ginseng water extract (KRGE) on angiogenesis and its underlying signal mechanism. This study showed that KRGE increased in vitro proliferation, migration, and tube formation of human umbilical endothelial cells, as well as stimulated in vivo angiogenesis. KRGE-induced angiogenesis was accompanied by phosphorylation of ERK1/2, Akt, and endothelial nitric oxide synthase (eNOS) as well as an increase in NO production. Inhibition of PI3K activity by wortmannin completely inhibited KRGE-induced angiogenesis and phosphorylation of Akt, ERK1/2, and eNOS, indicating that PI3K/Akt activation is an upstream event of KRGE-mediated angiogenic pathway. The MEK inhibitor PD98059 completely blocked KRGE-induced angiogenesis and ERK phosphorylation without affecting Akt and eNOS activation. However, the eNOS inhibitor NMA effectively inhibited tube formation, but partially blocked proliferation and migration as well as ERK phosphorylation without altering Akt and eNOS activation, revealing that eNOS/NO pathway is in part involved in ERK1/2 activation. This study first demonstrated the critical involvement of both ERK1/2 and eNOS activation in KRGE-induced angiogenesis, which lie on downstream of PI3K/Akt. Thus, these results indicate that KRGE requires activation of both the PI3K/Akt-dependent ERK1/2 and eNOS signal pathways and their cross-talk for its full angiogenic activity.

• Journal of Ginseng Research
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• v.38 no.3
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• pp.173-179
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• 2014

Background: Ginsenosides are the major components responsible for the biochemical and pharmacological actions of ginseng, and have been shown to have various biological activities. In this study, we investigated the antiviral activities of seven ginsenosides [protopanaxatriol (PT) type: Re, Rf, and Rg2; protopanaxadiol (PD) type: Rb1, Rb2, Rc, and Rd)] against coxsackievirus B3 (CVB3), enterovirus 71 (EV71), and human rhinovirus 3 (HRV3). Methods: Assays of antiviral activity and cytotoxicity were evaluated by the sulforhodamine B method using the cytopathic effect (CPE) reduction assay. Results: The antiviral assays demonstrated that, of the seven ginsenosides, the PT-type ginsenosides (Re, Rf, and Rg2) possess significant antiviral activities against CVB3 and HRV3 at a concentration of $100{\mu}g/mL$. Among the PT-type ginsenosides, only ginsenoside Rg2 showed significant anti-EV71 activity with no cytotoxicity to cells at $100{\mu}g/mL$. The PD-type ginsenosides (Rb1, Rb2, Rc, and Rd), by contrast, did not show any significant antiviral activity against CVB3, EV71, and HRV3, and exhibited cytotoxic effects to virus-infected cells. Notably, the antiviral efficacies of PT-type ginsenosides were comparable to those of ribavirin, a commonly used antiviral drug. Conclusion: Collectively, our findings suggest that the ginsenosides Re, Rf, and Rg2 have the potential to be effective in the treatment of CVB3, EV71, and HRV3 infection.

• Journal of the Korean Chemical Society
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• v.37 no.6
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• pp.599-603
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• 1993

Crystal structure of bis(1,2-diaminopropane)palladium(II) bis(oxalato)palladate(II) has been determined by X-ray crystallography. Crystal data: $Pd_2C_{10}H_{10}N_{4}O_{8}$, $M_W$ = 573.09, orthorhombic, space group $P_{ccn}$ (No = 56), a = 16.178(5), b = 16.381(6), c = 6.685(2)$\{AA}$, V = 1771.6 $\{AA}^3$, $M_W$W = 573.09, $D_c$ = 2.014 g${\cdot}c\;m^{-3}$, Z = 4, T = 294K, F(000) = 1056.0 and $\mu$ = 20.466 c$m^{-1}$. The intensity data were collected with $Mo-K\alpha$ radiation (${\lambda}$ = 0.7107 $\AA)$ on an automatic four-circle diffractometer with a graphite monochromater. The structure was solved by Patterson method and refined by full matrix least-squares methods using Pivot weights. The final R and S values were R = 0.065, $R_W = 0.059, R_{all}$ = 0.065 and S = 4.315 for 605 observed reflections. Both cation and anion complexes are essentially planar and have dihedral angle of $18(l)^{\circ}$ between thier planes. In the crystal structure, they do not have the Magnus's salt type mixed stacks; instead, the complex anions form regular stacks along the c-axis with the M-M bond length of $3.343(5)\AA$ and their stacks are surrounded by the complex cations through hydrogen bonds with the nitrogen-oxygen distances of 2.94(3) and $3.31(4)\AA.$

• Journal of the Korean Chemical Society
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• v.37 no.3
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• pp.327-333
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• 1993

A method was developed for the determination of trace elements in seawater by precipitate flotation preconcentration and subsequent flame atomic absorption detection. In order to quantitatively coprecipitate trace ions such as Cd(II), CuI(II), Fe(III), Mn(II), Pb(II) and Pd(II), 2.0 ml of 1.0M cerium(III) solution was added to 1.0l of seawater and the pH was adjusted to 9.5 with 5.0 M sodium hydroxide solution while stirring with a magnetic stirrer. The precipitate was floated with the aid of surfactant solution (1.0 ml of 0.3% sodium oleate) by bubbling nitrogen gas through a porous (No. 4) fritted glass disk. The floats was collected in a small Erlenmeyer flask by suction. The washed precipitate was dissolved in 8.0 M nitric acid and marked with deionized water in the volumetric flask of 10.0 ml. The analyte was determined by measuring the atomic absorbances in 100-fold concentrated solution. Above all analytes in Kangnung (East Sea) and Kanghwado (West Sea) sea waters were found to be under the detection limit of this method. The recoveries of over 92% for all analytes spiked into seawater samples showed that this method was applicable to the analysis of real seawater.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4151-4155
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• 2013

Background: To compare response evaluation criteria in solid tumours (RECIST) and volumetric evaluation (VE) for colorectal cancer with liver-limited metastasis. Patients and Methods: VE of liver metastases was performed by manual contouring before and after chemotherapy on 45 pairs of computed tomography (CT) images in 36 patients who suffered from metastatic colorectal cancer (mCRC) with liver metastasis only. Cohen kappa was used to compare the agreement between VE and RECIST. Pearson correlation was performed for their comparison after cubic root transformation of the aggregate tumor volumes. Logistic regression was done to identify clinical and radiographic factors to account for the difference which may be predictive in overall response (OR). Results: There were 16 partial response (PR), 23 stable disease (SD) and 6 progressive disease (PD) cases with VE, and 14 PR, 23 SD and 8 PD with RECIST. VE demonstrated good agreement with RECIST (${\chi}$=0.779). Discordant objective responses were noted in 6 pairs of comparisons (13.3%). Pearson correlation also showed excellent correlation between VE and RECIST ($r^2$=0.966, p<0.001). Subgroup analysis showed that VE was in slightly better agreement with RECIST for enlarging lesions than for shrinking lesions ($r^2$=0.935 and $r^2$=0.780 respectively). No factor was found predictive of the difference in OR between VE and RECIST. Conclusions: VE exhibited good agreement with RECIST. It might be more useful than RECIST in evaluation shrinking lesions in cases of numerous and conglomerate liver metastases.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.190-195
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• 2005

This research was conducted to investigate the changes in soil chemical properties of root media as influenced by incorporation rate of a polyacryl amide hydrogel, Stocksorb C. The pH at 5 weeks after treatment in four root media such as peatmoss + vermiculite (1:1, v/v; PV), peatmoss + composted rice hull (1:1; PR), peatmoss + composted saw dust (1:1; PD) and peatmoss + composted pine bark (1:1; PB) containing STSB were in the range from 7.04 to 7.30, which was too high. Elevated incorporation rate of STSB resulted in increase of EC in soil solution of four root media with linear and quadratic response. The concentrations of $NH_4^+-N,\;NO_3^--N,\;PO_4-P^{3-},\;K^+,\;Ca^{2+}and\;Mg^{2+}$ in four kinds of root media increased as incorporation rates of STSB were elevated. But the $NO_3^-$-N concentrations in PS media were lower than those in other there root media tested. The Fe concentrations in PV, PR and PS media increased as incorporation rates of STSB were elevated, but those in PB medium did not show significant different. The concentrations of $Fe^{2+},\;Mn^{2+},\;Zn^{2+}and\;Cu^{2+}$ in PS media were higher than those in other three root media.

• Journal of Periodontal and Implant Science
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• v.38 no.3
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• pp.521-528
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• 2008

Purpose: Tunneling is a periodontal surgical procedure that creates access for patient cleansing and maintenance within the furcal area of a molar tooth with severe furcation involvement. Up to date, there are few studies about a long term clinical and radiographic stability of tunneling. The purpose of this retrospective study is to evaluate the long term prognosis after tunnel preparation of molars with through and through furcation. Material and Methods: 25 teeth of 23 patients aged 36 to 70 (mean age 51.7) were treated surgically with tunnel preparation. These cases were followed for 2 to 13 years (mean 6.5years) after surgery. Patients were recalled for an evaluation which was based on a questionnaire, a clinical examination, and radiographic analysis. Clinical assessment included plaque index, caries registration, probing pocket depth, bleeding on probing, tooth mobility. Baseline and over 2-year follow-up radiographs were collected and evaluated for this study. Result: 3 teeth(12%) had been extracted and 1 tooth(4%) hemisected. Root caries was detected in 3 teeth(12%). Thus 72% of the teeth were still caries tree and in function. Clinical parameters including PI, PD, BOP, mobility showed somewhat favourable results. Radiographic furcal bone loss showed no statistically significant difference compared to interproximal crestal bone loss ($3.59{\pm}1.69%$ vs $3.42{\pm}2.95%$) when root length was used as reference. There was no correlation between root trunk length and furcal bone loss. Conclusion: Over 2 years after tunneling procedure, teeth showed a clinically and radiographically stable condition, despite of slight root caries and alveolar bone loss within clinically acceptable range. The tunnel procedure may be considered as a viable periodontal treatment option for molar teeth with severe furcation involvement in individuals following a regular maintenance program.

• Journal of Life Science
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• v.27 no.1
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• pp.8-14
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• 2017

Died Gardenia jasminoides fruit is used as a dye in the food and clothes industries in Asia. The present study investigated the anti-inflammatory effects of aqueous extract of G. jasminoides fruits (GJ) in BV-2 microglial cells. GJ inhibited lipopolysaccharide-induced nitric oxide (NO) secretion, inducible nitric oxide synthase (iNOS) expression, and reactive oxygen species production, without affecting cell viability. Furthermore, GJ increased the expression of heme oxygenase-1 (HO-1) in a dose-dependent manner. Moreover, the inhibitory effect of GJ on iNOS expression was abrogated by small interfering RNA-mediated knock-down of HO-1. In addition, GJ induced nuclear translocation of nuclear factor E2-related factor 2 (Nrf2), a transcription factor that regulates HO-1 expression. GJ-mediated expression of HO-1 was suppressed by LY294002, a phosphoinositide 3-kinase (PI-3K) inhibitor, and SB203580, a p38 kinase inhibitor, but not by the extracellular signal-regulated kinase (ERK) inhibitor PD98059 or c-Jun N-terminal kinase (JNK) inhibitor SP600125. GJ also enhanced the phosphorylation of Akt and p38. These results suggest that GJ suppresses the production of NO, a pro-inflammatory mediator, by inducing HO-1 expression via PI-3K/Akt/p38 signaling. These findings illustrate a novel molecular mechanism by which extract from G. jasminoides fruits inhibits neuroinflammation.