• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3482-3488
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• 2014

Matrix-induced mass bias and its effect on the accuracy of isotope ratio measurements have been examined for a quadrupole-based inductively coupled plasma-mass spectrometer (Q ICP-MS). Matrix-induced mass bias effect was directly proportional to % mass difference, and its magnitude varied for element and nebulizer flow rate. For a given element and conditions in a day, the effect was consistent. The isotope ratio of Cd106/Cd114 under $200{\mu}g\;g^{-1}$ U matrix deviated from the natural value significantly by 3.5%. When Cd 111 and Cd114 were used for the quantification of Cd with isotope dilution (ID) method, the average of differences between the calculated and measured concentrations was -0.034% for samples without matrix ($0.076{\mu}g\;g^{-1}$ to $0.21{\mu}g\;g^{-1}$ for the period of 6 months). However, the error was as large as 1.5% for samples with $200{\mu}g\;g^{-1}$ U. The error in ID caused by matrix could be larger when larger mass difference isotopes are used.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.901-902
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• 2003

Three-color organic light-emitting diodes (OLEDs) of metal-semiconductor-metal (MSM) structure have been favricated by using m-MTDATA [4,4',4"-tris (3-methylphenylphenylamino) triphenylamine] as hole injection layer(HIL). The mMTDATA is shown to be an effective hole injecting material, in that the insertion of mMTDATA greatly reduces the roughness of anode surface and improves the device performance. Red, green and blue OLEDs were fabricated, and their color coordinates in CIE chromaticity were found to be (0.600, 0.389), (0.240, 0.525), and (0.171, 0.171), respectively. The luminous efficiencies of the fabricated OLEDs were 1.4 lm/W at 106 $cd/m^{2}$ for red, 1.4 lm/W at 100 $cd/m^{2}$ for green, and 2.0 lm/W at 104 $cd/m^{2}$ for blue.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.144-145
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• 2009

Single crystal $CdGa_2Se_4$ layers were grown on a thoroughly etched semi-insulating GaAs(100) substrate at $420^{\circ}C$ with the hot wall epitaxy (HWE) system by evaporating the poly crystal source of $CdGa_2Se_4$ at $630\;^{\circ}C$. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of single crystal $CdGa_2Se_4$ thin films measured with Hall effect by van der Pauw method are $8.27\;\times\;10^{17}\;cm^{-3}$, $345\;cm^2/V{\cdot}s$ at 293 K, respectively. The photocurrent and the absorption spectra of $CdGa_2Se_4$/SI(Semi-Insulated) GaAs(100) are measured ranging from 293 K to 10K. The temperature dependence of the energy band gap of the $CdGa_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T) = 2.6400 eV - ($7.721\;{\times}\;10^{-4}\;eV/K)T^2$/(T + 399 K). Using the photocurrent spectra and the Hopfield quasi cubic model, the crystal field energy(${\Delta}cr$) and the spin-orbit splitting energy(${\Delta}so$) for the valence band of the $CdGa_2Se_4$ have been estimated to be 106.5 meV and 418.9 meV at 10 K, respectively. The three photocurrent peaks observed at 10 K are ascribed to the $A_1$-, $B_1$-, and $C_{11}$-exciton peaks.

• Journal of Korean Neurosurgical Society
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• v.58 no.2
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• pp.101-106
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• 2015

Objective : The aim of this study was to explore the immunity in rats transplanted with adipose-derived mesenchymal stem cells (ADSCs) and acellular nerve (ACN) for repairing sciatic nerve defects. Methods : ADSCs were isolated from the adipose tissues of Wistar rats. Sprague-Dawley rats were used to establish a sciatic nerve defect model and then divided into four groups, according to the following methods : Group A, allogenic nerve graft; Group B, allograft with ACN; Group C, allograft ADSCs+ACN, and Group D, nerve autograft. Results : At the day before transplantation and 3, 7, 14, and 28 days after transplantation, orbital venous blood of the Sprague-Dawley rats in each group was collected to detect the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets using flow cytometry and to determine the serum concentration of interleukin-2 (IL-2), tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) and $interferon-{\gamma}$ ($IFN-{\gamma}$) using enzyme-linked immunosorbent assay (ELISA). At each postoperative time point, the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets and the serum concentration of IL-2, $TNF-{\alpha}$, and $IFN-{\gamma}$ in group C were all near to those in group B and group D, in which no statistically significant difference was observed. As compared with group A, the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets and the serum concentration of IL-2, $TNF-{\alpha}$, and $IFN-{\gamma}$ were significantly reduced in group C (p<0.05). Conclusion : The artificial nerve established with ADSCs and ACN has no obvious allograft rejection for repairing rat nerve defects.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.105-106
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• 2008

Structural, optical and electrical properties of CdS films deposited by chemical bath deposition (CBD), which are a very attractive method for low-cost and large-area solar cells, are presented. Cadmium sulfide (CdS) is II-VI semiconductor with a wide band gap of approximately 2.42 eV. CdS films have a great application potential such as solar cell, optical detector and optoelectronics device. In this paper, effects of Rapid Thermal Process (RTP) on the properties of CdS films were investigated. The CdS films were prepared on a glass by chemical bath deposition (CBD) and subsequently annealed at standard temperature $(400^{\circ}C)$ and treatment time (10 min) in various atmospheres (air, vacuum and $N_2$). The CdS films treated RTP in $N_2$ for to min were showed larger grain size and higher carrier density than the other samples.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7513-7516
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• 2015

Background: Pyogenic granuloma is a common non-neoplastic connective tissue proliferation. ICAM-1 and VCAM-1 are vascular adhesion molecules and CD34 is a marker for evaluation of angiogenesis. The purpose of this study was to compare the immunohistochemical expression of ICAM-1, VCAM-1 & CD34 in oral pyogenic granuloma and normal gingiva. Materials and Methods: This study was performed on thirty five formalin-fixed, paraffin embedded samples of gingival pyogenic granuloma. Also we used thirty five paraffined blocks of normal gingiva as control group which were taken from crown lengthening surgery. We employed immunohistochemistry staining for our prepared microscopic slides using monoclonal mouse anti-human antibodies against ICAM-1 (CD54), VCAM-1 (CD106) and CD34. Slides were examined under light microscope and then the mean amount of stained vessels also known as microvascular density (MVD) in highly vascularized areas (hot spots) was measured. Paired t-test and repeated measures ANOVA were used to compare the difference between quantitative variables and Chi-square test for qualitative variables in different groups. Pearson correlation coefficient was used to compare relations between quantitative variables. P<0.05 was considered significant. Results: The mean of MVD for ICAM-1, VCAM-1 and CD34 was significantly higher in pyogenic granuloma than normal gingiva (p<0.001 & p<0.001 & p<0.001, respectively). Expression of CD34 in pyogenic granuloma was significantly higher than ICAM-1 and VCAM-1 (P<0.001). Besides, expression of ICAM-1 in normal gingiva, was significantly lower than two other markers (p<0.001). Conclusions: Regarding the results, it seems that ICAM-1, VCAM-1 and CD34 are useful biomarkers in evaluation of vascular and inflammatory lesions such as gingival pyogenic granuloma and the results indicate the role of these biomarkers in pathogenesis of oral pyogenic granuloma.

• TTA Journal
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• s.156
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• pp.106-109
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• 2014

일본은 CD-DVD-Blueray로 이어지는 정보 저장기기 국제표준화 주도에서 볼 수 있듯이 표준의 역사와 경험에 있어서는 한국에 월등히 앞섬은 물론 세계를 주도한 국가였다. 그러나 최근의 산업 현장에서의 동향을 보면 표준활동의 폭과 깊이가 예전에 못 미치는 것이 현실이다. 왜 이런 현상이 벌어졌는 지를 고찰해 보는 것도 우리의 표준역량을 높이는 과정에서 의미있는 일이 될 것 같다.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.2
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• pp.99-106
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• 2009

Although anti-atherogenic effects of cilostazol have been suggested, its effects on the expression of SR in macrophages are unclear. This study investigated the role of cilostazol on CD36 expression of murine macrophages enhanced by HNE, a byproduct of lipid peroxidation. The stimulation of macrophages with HNE led to an increased expression of CD36, which was significantly attenuated by NAC, an antioxidant. Moreover, the increased production of ROS by HNE was completely abolished by NADPH oxidase inhibitors, DPI and apocynin, as well as by the 5-LO inhibitor, MK886, but not by inhibitors for other oxidases. This suggested that NADPH-oxidase and 5-LO were major sources of ROS induced by HNE. In addition, HNE-enhanced expression of CD36 was reduced by these inhibitors, which indicated a role for NADPH oxidase and 5-LO on CD36 expression. In our present study, cilostazol was a significant inhibitor of ROS production, as well as CD36 expression induced by HNE. An increase in NADPH oxidase activity by HNE was significantly attenuated by cilostazol, however cilostazol had no effect on HNE-enhanced 5-LO activity. Together, these results suggest that cilostazol attenuates HNE-enhanced CD36 expression on murine macrophages thorough inhibition of NADPH oxidase-derived ROS generation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.124-125
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• 2007

Single crystal $CdGa_2Se_4$ layers were grown on a thoroughly etched semi-insulating GaAs(100) substrate at $420^{\circ}C$ with the hot wall epitaxy (HWE) system by evaporating the polycrystal source of $CdGa_2Se_4$ at $630^{\circ}C$ prepared from horizontal electric furnace. The photocurrent and the absorption spectra of $CdGa_2Se_4$/SI(Semi-Insulated) GaAs(100) are measured ranging from 293K to 10K. The temperature dependence of the energy band gap of the $CdGa_2Se_4$, obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T) = 2.6400 eV - $(7.721{\times}10^{-4}\;eV/K)T^2$/(T + 399 K). Using the photocurrent spectra and the Hopfield quasicubic model, the crystal field energy$({\Delta}cr)$ and the spin-orbit splitting energy$({\Delta}so)$ for the valence band of the $CdGa_2Se_4$ have been estimated to be 106.5 meV and 418.9 meV at 10 K, respectively. The three photocurrent peaks observed at 10 K are ascribed to the $A_{1^-},\;B_{1^-},\;and\;C_{11^-}$ exciton peaks.

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.412-419
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• 2004

In odor to select optimum extraction methods of volatile compounds in beef extract powder(BEP) as basic data for the development of a new detection method of irradiated BEP, four extraction methods, such as solid phase microextraction with polar fiber(S-PD) and non-polar fiber(S-CD), purge and trap(P&T) and liquid liquid continuous extraction(LLCE) methods, were tested with gas chromatography/mass spectrometry method. A total of 106 volatile compounds including 22 hydrocarbons, 7 aldehydes, 6 ketones, 13 alcohols, 6 sulfur-containing compounds, 19 nitrogen-containing compounds, 6 aromatic compounds, 17 terpenes, 8 furans and 2 miscellaneous compounds were detected in BEP by four detection methods. The most compounds(62 compounds) were detected by S-PD method, followed by P&T(43), LLCE(38) and S-CD method(30). Among these methods, S-PD and P&T methods showed a complementary interrelationship to detect volatile compounds as S-PD method showed high detectabiltiy to all compound groups except hydrocarbons and ketones, which had high volatility and low molecular weight(less than RI 1200), but P&T method showed the contrary pattern to that of S-PD method. Moreover, the most of volatile compounds detected by S-CD and LLCE methods were also detectable by S-PD or/and P&T methods. Therefore, the simultaneous application of S-PD and P&T methods were selected as the optimum volatile extraction methods of BEP.