• Toxicological Research
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• v.17
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• pp.89-96
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• 2001

Recently, considerable attention has been focused on the role of cyclooxygenase-2 (COX-2) in the carcinogenesis as well as in inflammation. Improperly overexpressed COX-2 has been observed in many types of human cancers and transformed cells in culture. Thus, it is conceivable that targeted inhibition of abnormally or improperly up-regulated COX-2 provides one of the most effective and promising strategies for cancer prevention. A ubiquitous eukaryotic transcription factor, NF-kB is considered to be involved in regulation of COX-2 expression. Furthermore, extracellular-regulated protein kinase and p38 mitogen-activated protein (MAP) kinase appear to be key elements of the intracellular signaling cascades involved in NF-kB activation in response to a wide array of external stimuli. Certain chemopreventive phytochemicals suppress activation of NF-kB by blocking one or more of the MAP kinases, which may contribute to their inhibitory effects on COX-2 induction. One of the plausible mechanisms by which chemopreventive phytochemicals inhibit NF-kB activation involves suppression of degradation of the inhibitory unit I kB, which hampers subsequent translocation of p65, the functionally active subunit of NF-kB.

• Communications of the Korean Mathematical Society
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• v.35 no.3
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• pp.745-757
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• 2020

A set {a₁, a₂, …, a_m} of positive integers is called a Diophantine m-tuple if a_ia_j + 1 is a perfect square for all 1 ≤ i < j ≤ m. In this paper, we find the structure of a torsion group of elliptic curves E_k constructed by a Diophantine triple {F_2k, F_2k+2, 4F_2k+1F_2k+2F_2k+3}, and find all integer points on the elliptic curve under assumption that rank(E_k(ℚ)) = 2.

• Progress in Superconductivity and Cryogenics
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• v.5 no.3
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• pp.20-22
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• 2003

Y$_2$O$_3$ films were pulsed laser deposited on cube textured Ni and Ni-W substrates to be used as a single buffer layer of YBCO coated conductor. Initial deposition of $Y_2$O$_3$ films was performed in a reducing atmosphere, and subsequent deposition was done in the base pressure of the chamber and oxygen atmosphere. The $Y_2$O$_3$ films have a strong cube texture (The full width at half maximum of the ø-scan of $Y_2$O$_3$ was 8.4 which was the same as that of metal substrate) and smooth crack-free microstructure. The biaxially textured YBCO films (The full width at half maximum of the ø-scan was 10.2) pulsed laser deposited on the $Y_2$O$_3$/metal exhibited Tc(R=0) of 86.5K and Jc of 0.7 MA/cm2 at 77K in self field, representing that the $Y_2$O$_3$ single buffer layer is an efficient diffusion barrier of Ni and thus very promising for the achievement of high-Jc YBCO coated conductor.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.5
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• pp.1251-1256
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• 2003

To determine the effect of Zibachunggan-tang(ZCT) on the process of lipopolysaccharide (LPS)-induced nuclear factor-kBp65 (NF-kBp65) activation, and LPS-induced expression of pro-inflammatory proteins including tumor necrosis factor-α (TNF-α), nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), in HepG2 cell. Immunoblot analysis showed that the level of nucleic NF-kBp65 was rapidly up-regulated and cytosolic inhibitory I-kBα was down-regulated by LPS challenge. While ZCT inhibited an increase of NF-kBp65 and degradation of I-kBα in HepG2 cell. Beside LPS-induced expression of a group of genes, such as TNF-α, inducible iNOS and COX-2, are repressed by ZCT. It may be concluded that ZCT attenuates the progress of LPS-induced inflammation by reduction of NF-kBp65 activation. The ZCT would be useful as a therapeutic agent for endotoxin-induced liver disease.

• Journal of Magnetics
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• v.20 no.3
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• pp.211-214
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• 2015

$Cr_2O_3$ nanoparticles were prepared via one-step reactive laser ablation of Cr in oxygen. The metastable $CrO_2$ phase was obtained through the subsequent oxidation of $Cr_2O_3$ nanoparticles under $O_2$ with gas pressures of up to 40 MPa. The as-prepared $Cr_2O_3$ nanoparticles are spherical or rectangular in shape with sizes ranging from 20 nm to 50 nm. High oxygen pressure annealing is effective in producing meta-stable $CrO_2$ from as-dried $Cr_2O_3$ nanoparticles, and the $Cr_2O_3$ nanoparticles exhibit a weak ferromagnetic behavior with an exchange bias of up to 11 mT that can be ascribed to the interfacial exchange coupling between uncompensated surface spins and the antiferromagnetic core. The $Cr_2O_3/CrO_2$ nanoparticles exhibit an enhanced saturation magnetization and a reduced exchange bias with an increasing faction of $CrO_2$ due to the elimination of uncompensated surface spins over the $Cr_2O_3$ nanoparticles when exposed to a high pressure of $O_2$ and/or possible phase segregation that results in a smaller grain size for both $Cr_2O_3$ and $CrO_2$.

• Journal of the Korean Chemical Society
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• v.44 no.3
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• pp.281-285
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• 2000

• Proceedings of the KAIS Fall Conference
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• 2008.11a
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• pp.339-342
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• 2008

Methacrylate와 Cyclopentadiene을 반응하여 5-methylbicyclo[2.2.1]hept-2-ene-5-carboxylate (MBHC)를 합성하고 만들어진 MBHC를 Column Chromatography를 이용하여 Endo와 Exo를 분리하였고, MBHC에 붙는 작용기에 따른 수율 및 Endo, Exo의 비율을 확인하였다.

• Proceedings of the KIEE Conference
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• 2008.05a
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• pp.127-128
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• 2008

현재 산업사회의 발달과 더불어 신뢰성 높은 양질의 전기에너지와 운전 및 보수의 간편화, 계통운용의 신뢰성의 확보가 요구되고 있다. 또한 $SF_6$을 대체할 친환경적인 절연매체의 개발이 절실히 요구되고 있다. 이에 본 연구는 모의 GIS내 친환경적인 절연재료인 질소($N_2$)와 산소($O_2$)의 혼합가스($N_2:O_2=79:21$, $N_2:O_2=60:40$, $N_2:O_2=40:60$)과 Dry-Air 기본적인 절연 특성을 밝혀, 각종 전력응용 설비의 절연매체로 사용가능함을 구명하고저 한다.

• The Bulletin of The Korean Astronomical Society
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• v.32 no.2
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• pp.32.2-32.2
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• 2007

• Korean Journal of Materials Research
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• v.23 no.6
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• pp.309-315
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• 2013

$GdBa_2Cu_3O_{7-y}$(Gd123) powders were synthesized by the solid-state reaction method using $Gd_2O_3$ (99.9% purity), $BaCO_3$ (99.75%) and CuO (99.9%) powders. The synthesized Gd123 powder and the Gd123 powder with $Gd_2O_3$ addition ($Gd_{1.5}Ba_2Cu_3O_{7-y}$(Gd1.5)) were used as raw powders for the fabrication of Gd123 bulk superconductors. The Gd123 and Gd1.5 bulk superconductors were fabricated by sintering or a top-seeded melt growth (TSMG) process. The superconducting transition temperature ($T_{c,onset}$) of the sintered Gd123 was 93 K and the transition width was as large as 20 K. The $T_{c,onset}$ of the TSMG processed Gd123 was 82 K and the transition width was also as large as 12 K. The critical current density ($J_c$) at 77 K and 0 T of the sintered Gd123 and TSMG processed Gd123 were as low as a few hundreds A/$cm^2$. The addition of 0.25 mole $Gd_2O_3$ and 1 wt.% $CeO_2$ to Gd123 enhanced the $T_c$, $J_c$ and magnetic flux density (H) of the TSMG processed Gd123 sample owing to the formation of the superconducting phase with high flux pinning capability. The $T_c$ of the TSMG processed Gd1.5 was 92 K and the transition width was 1 K. The $J_cs$ at 77 K (0 T and 2 T) were $3.2{\times}10^4\;A/cm^2$ and $2.5{\times}10^4\;A/cm^2$, respectively. The H at 77 K of the TSMG-processed Gd1.5 was 1.96 kG, which is 54% of the applied magnetic field (3.45 kG).