• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2145-2150
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• 2016

Background: Infection with hepatitis B virus (HBV) is a major global public health problem, with a wide spectrum of clinical manifestations. Human cytosolic glutathione-S-transferases (GSTs) include several classes such as alpha (A), mu (M), pi (P), sigma (S), zeta (Z), omega (O) and theta (T). The present study aimed to investigate the role of GST omega genes (GSTO1 and GSTO2) in different groups of patients infected with HBV. Materials and Methods: HBV groups were classified according to clinical history, serological tests and histological analysis into normal carriers (N), acute (A), chronic (CH), cirrhosis (CI) and hepatocellular carcinoma (HCC) cases. The study focused on determination of the genotypes of GST omega genes (GSTO1 and GSTO2) and GST activity and liver function tests. Results: The results showed that GSTO1 (A/A) was decreased in N, A, CH, CI and HCC groups compared to the C-group, while, GSTO1 (C/A) and GSTO1(C/C) genotypes were increased significantly in N, A, CH, CI and HCC groups. GSTO2 (A/A) was decreased in all studied groups as compared to the C-group but GSTO2(A/G) and GSTO2(G/G) genotypes were increased significantly. In addition, GST activities, albumin and TP levels were decreased in all studied groups compared to the C-group, while the activities of transaminases were increased to differing degrees. Conclusions: The results indicate that GSTO genetic polymorphisms may be considered as biomarkers for determining and predicting the progression of HBV infection.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.115.2-115.2
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• 2011

UWISH2 (UKIRT Widefield Infrared Survey for $H_2$) is an unbiased, narrow-band imaging survey of the Galactic plane in the $H_2$ 1-0 S(1) emission line at $2.122{\mu}m$ using the Wide-Field Camera (WFCAM) at the United Kingdom Infrared Telescope (UKIRT). The survey covers about 150 square degrees of the first Galactic quadrant ($10^{\circ}$ < l < $65^{\circ}$; $-1.3^{\circ}$ < b < $+1.3^{\circ}$). The images have a $5{\sigma}$ detection limit of point sources of K~18 mag and the surface brightness limit is $10^{-19}\;W\;m^{-2}$ $arcsec^{-2}$. The survey operation began on 28 July 2009 and has completed on 17 August 2011. We have been studying the supernova remnants (SNRs) in the UWISH2 survey area. Among the known 274 Galactic SNRs, the survey area includes 65 SNRs or 24 percent of the known SNRs. The wide-field and high-quality UWISH2 images allow us to identify both the diffuse extended and compact $H_2$ emission associated with SNRs, which is useful for understanding their physical environment and evolution. The continuum is subtracted from the narrow-band $H_2$ images using the K-band continuum images obtained as part of the UKIDSS GPS (UKIRT Infrared Deep Sky Survey of the Galactic Plane). So far, we have inspected 42 SNRs, and found distinct H2 emission in 14 SNRs. The detection rate is 33%. Some of the SNRs show bright, complex, and interesting structures that have never been reported in previous studies. In this report, we present our identification scheme and preliminary results.

• Special Issue of the Society of Naval Architects of Korea
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• 2011.09a
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• pp.117-126
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• 2011

The buckling assessment of plate panels described in common structural rules (CSR) is to be determined according to the buckling utilization factor with hull girder stresses calculated on net hull girder sectional properties. As the thickness requirement for the buckling assessment of plate panels is not explicitly given in CSR, a lot of time is spent to find the proper thickness of plate panels until reaching to an allowable buckling utilization factor. In this study, in order to reduce time and cost, the thickness requirement of plate panels satisfying buckling assessment was derived. The structural design system included with the thickness requirement for buckling assessment was developed. The system is called as Oil-tanker Automated Structural Investigation System (OASIS). The design result of longitudinal strength members using OASIS was verified by Nauticus Hull which is the rule scantling software of DNV. Finally, optimum design of a double hull tanker for the minimum weight using OASIS was presented.

• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.2
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• pp.100-105
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• 2004

The influencing factors on the OPC (optical proximity correction) results are quantitatively analyzed using OPCed L/S patterns. ${\sigma}$ values of proximity variations are measured to be 9.3 nm and 15.2 nm for PR-A and PR-B, respectively. The effect of post exposure bake condition is assessed. 16.2 nm and 13.8 nm of variations are observed. Proximity variations of 11.6 nm and 15.2 nm are measured by changing the illumination condition. In order not to seriously deteriorate the OPC, these factors should be fixed after the OPC rules are extracted. Proximity variations of 11.4, 13.9, and 15.2 nm are observed for the mask mean-to-targets of 0, 2 and 4 nm, respectively. The decrease the OPC grid size from 1 nm to 0.5 nm enhances the correction resolution and the OCV is reduced from 14.6 nm to 11.4 nm. The enhancement amount of proximity variations are 9.2 nm corresponding to 39% improvement. The critical dimension (CD) uniformity improvement for adopting the small grid size is confirmed by measuring the CD uniformity on real SRAM pattern. CD uniformities are measured 9.9 nm and 8.7 nm for grid size of 1 nm and 0.5 nm, respectively. 22% improvement of the CD uniformity is achieved. The decrease of OPC grid size is shown to improve not only the proximity correction, but also the uniformity.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1704-1710
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• 2010

The structure of a 2D grid-like copper(II) complex [Cu$(NCO)_2$(pyz)](pyz=pyrazine) (1) consists of 1D chains of Cu-pyz units connected by double end-on (EO) cyanato bridges. Each Cu(II) ion has a distorted octahedral coordination, completed by the four EO cyanato and two pyrazine ligands. Magnetic interactions through EO cyanato and pyrazine bridges in 1 are discussed on the basis of DFT broken-symmetry calculations at the B3LYP level. For model dicopper(II) complexes I (bridged by cyanato) and II (bridged by pyrazine), electronic structure calculations reproduce very well the experimental couplings for the S = 1/2 ferromagnetic and antiferromagnetic exchange-coupled 2D system: the calculated exchange parameters J are +1.25 $cm^{-1}$ and -3.07 $cm^{-1}$ for I and II, respectively. The $\sigma$ orbital interactions between the Cu $x^2-y^2$ magnetic orbitals and the nitrogen lone-pair orbitals of pyrazine are analyzed from the viewpoint of through-bond interaction. The energy splitting of 0.106 eV between two SOMOs indicates that the superexchange interaction should be antiferromagnetic in II. On the other hand, there are no bridging orbitals that efficiently connect the two copper(II) magnetic orbitals in I because the HOMOs of the basal-apical NCO bridge do not play a role in the formation of overlap interaction pathway. The energy separation in the pair of SOMOs of I is calculated to be very small (0.054 eV). This result is consistent with the occurrence of weakly ferromagnetic properties in I.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.53.2-53.2
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• 2016

We present surface photometry results of the dwarf galaxies in the nearby NGC 2784 galaxy group. We newly detected about 30 dwarf galaxy candidates at about 30 square degree area around the nearby NGC 2784 galaxy (D~10 Mpc and MV=-20.5) applying a visual inspection technique on the wide-field optical images taken by the KMTNet Supernova Program (KSP). Surface brightnesses of the objects estimated from the stacked-images with total exposure time of about 6 hours reach approximately ${\mu}V$ ~28.5 mag/arcsec2 around $3{\sigma}$ above sky background. The central surface brightness and the total absolute magnitude for the faintest candidate dwarf galaxy among about 40 galaxies including the previously known ones is ${\mu}0$, V~26.1 mag/arcsec2 and MV~-9.5 mag, respectively. The effective radii of the candidates are larger than ~200 pc. The radial number density of the dwarf galaxy candidates from the center of NGC 2784 is decreasing. The mean color (<(B-V)0>~0.7) and $S{\acute{e}}rsic$ structure parameters of the dwarfs, assuming them to be located in the NGC 2784 group, are well consistent with those of the dwarf galaxies in other groups (e.g. M83 group and the Local Group (LG)). The faint-end slope of the cumulative luminosity function (CLF) of the galaxies in NGC 2784 group is about ${\alpha}=-1.2$, which is steeper than that of the LG galaxies, but is much flatter than that of the CLF expected by a ${\Lambda}CDM$ model.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.1_2
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• pp.77-88
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• 1992

Recently, diabetic patients are increasing in the field of microvascular surgery. Diabetes melltius is known to be related to arterial damage, platelet malfunction and thrombus formation. After microvascular anastomosis, delayed repair and vascular occlusion occurred more frequently in diabetic state. This study was performed to investigate the patency rate and process of endothelial healing after microvascular anastomosis of femoral artery in diabetic rat by scanning electron microscope. The animals were divided into two groups, 20 diabetic-induced and 20 non-diabetic groups. Diabetes was induced with a injection of Streptozotocin(50mg/kg b.w., Sigma Chemical Co.) to tail vein. The results obtained were as follows: 1. Macroscopically, anastomotic site was intact except a few cases showed minimal inflammatory sign around the wound site. But the inflammatory change was frequently occurred in diabetic-induced group. 2. The patency rate was 95% (19/20) in non-diabetic group and 65% (13/20) in diabetic-induced group. 3. In the non-diabetic group, anstomotic region was mostly endothelized by the alignment along the long axis of vessel but stitchs were not covered with endothelial cells. The thichkening of vessel wall was not observed. 4. In the diabetic-induced group, anastomotic region was not endothelized but covered with blood cellular components and connective tissue instead of endothelial cells. The thickening of the vessel wall was prominent in some diabetic-induced rats. These results suggest that diabetes was related to delayed regeneration of endothelium of vessels after microsurgical anastomosis.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1938-1940
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• 2003

본 연구는 요소 센서 제작을 위한 과정으로서, 전기화학적 방법을 이용한 다공질 실리콘 구조 형성과, PDV(Physical Vapor Deposition) 법에 의한 백금 박막 코팅 및 전기화학적 전도성 고분자 코팅과 urease 고정화 단계를 고찰하고 감도 특성을 제시 하였다. 전극 기질로서 B을 도우핑한 p-type 실리콘웨이퍼를 사용하였고, HF:$C_2H_5OH:H_2O$=1:2:1의 부피비를 갖는 에칭 용액에서 5분간 -7 $mA/cm^2$의 일정 전류를 가하여 폭 2 ${\mu}m$, 깊이 10 ${\mu}m$의 다공질 실리콘(PS) 충을 형성하였다. 그 위에 200 ${\AA}$의 Ti 층을 underlayer로서 증착하고, 2000 ${\AA}$의 Pt를 중착하여 PS/Pt 박막 전극을 제작하고, 전도성 고분자로서 polypyrrole (PPy), 또는 poly(3-mehylthiophene) (P3MT)을 전기화학적으로 코팅한 후, urease(EC 3.5.1.5, type III, Jack Bean, Sigma)를 고정화 하였다. 고정화 시 전해질 수용액의 pH는 7.4로 하여 urease표면이 음전하를 갖도록 하고, 전극에 0.6 V (vs. SCE(Saturated Calomel Electrode))의 일정 전압을 가함으로써 urease가 전도성 고분자 표면에 전기적으로 흡착되도록 하였다. 이상의 방법으로 제작한 요소 센서의 감도는 PPy와 P3MT를 전자 전달 매질로 사용한 경우, 각각 8.44 ${\mu}A/mM{\cdot}cm^2$와 1.55 ${\mu}A/mM{\cdot}cm^2$의 감도를 보였다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.8
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• pp.703-709
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• 2017

Creep analysis takes much more time than elastic or elastic-plastic analysis. In this study, we conducted elastic and elastic-plastic analysis and compared the results with creep analysis results. In the elastic analysis, we used primary stress, which can be classified by the $M{\alpha}-tangent$ method and stress intensities recommended in the ASME code. In the elastic-plastic analysis, we calculated the parameters recommended in the R5 code. For the FE models, a bending load, uniaxial load, and biaxial load were applied to the cross shaped welded plate, and a bending load and internal pressure were applied to the elbow pipe. To investigate the element size sensitivity, we conducted FE analysis for various element sizes for the cases where bending load was applied to the cross shaped welded plate. There was no significant difference between the creep stress and the alternative methods; however, in the $M{\alpha}-tangent$ method, the results were affected by the element size.

• Nuclear Engineering and Technology
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• v.8 no.4
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• pp.203-207
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• 1976

Strain rate dependence of the flow stress of cold-worked and annealed Zircaloy-4 was studied by stress relaxation test in temperature range of 20$0^{\circ}C$ to 45$0^{\circ}C$. The In $\sigma$-ln i curves for various temperatures were straight in the eirange of 10$^{-5}$ to 10$^{-3}$ sec$^{-1}$ . From the slope of a curve strain rate sensitivity m was obtained. The m in cold-worked Zircaloy-4 had a minimum value at 30$0^{\circ}C$, while m in annealed Zircaloy-4 had two minimum values, one at 30$0^{\circ}C$ and the other at 45$0^{\circ}C$. It was found that the temperatures of the minimum m are consistent with the temperatures of strain ageing peaks. The minimum m at 30$0^{\circ}C$ is considered to be due to strain ageing owing to the pinning of glide dislocations by oxygen atoms, while the minimum m at 45$0^{\circ}C$ for annealed specimen is attributed to iron atoms.