• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.348-351
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• 1988

The production of extracellular $\alpha$-amylase by Bacillus thuringiensis 19 serotypes was examined by the hydrolysis test of starch. Thirteen serotypes produced the amylase. B. thuringiensis serovar thuringiensis alesti, kurstaki, sotto, kenya, israelensis, morrisoni, entomocidus, tolworthi, thompsoni, toumanoffi, pakistani, and indiana produced tee enzyme. The amylase produced by B. thuringiensis serovar israelensis showed highest activity around pH 6.7 to 7.2 and 55$^{\circ}C$ to $65^{\circ}C$. The high production medium of the amylase was composed of 1% bactopeptone, 0.3% beef-extract, 0.3% yeast ex-tract, 0.5% NaCl, 0.3% $K_2$HPO$_4$, 0.1% KH$_2$PO$_4$, 0.2% Soluble Starch, 0.012% CaCl$_2$.2$H_2O$$_2$, 0.005% MnCl$_2$, and 0.03% MgCl$_2$.7$H_2O$. The highest production of the enzyme was observed at 4 hours culture in the soluble starch (0.6 units/$m\ell$) or glucose (0.43 units/$m\ell$) substrate.

• Microbiology and Biotechnology Letters
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• v.50 no.3
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• pp.354-360
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• 2022

This research was designed to evaluate the possible anti-inflammatory effects of Carex scabrifolia Steud. extract using RAW264.7 cells. The assessments of these effects were based on cell viability assay, mRNA expression levels of interleukin-1 alpha (IL-1α), interleukin-1 beta (IL-1β), IL-6, tumor necrosis factor alpha (TNFα), and levels of nitric oxide (NO)/prostaglandin E2 (PGE₂) production. Quantitative real-time polymerase chain reaction showed that treatment with C. scabrifolia Steud. extract decreased the mRNA levels of iNOS, COX2, IL-1α, IL-1β, IL-6, and TNFα. Furthermore, from the production levels of PGE₂/NO, it can be inferred that C. scabrifolia Steud. extract exhibited anti-inflammatory properties. These results suggest that C. scabrifolia Steud. extract contains anti-inflammatory compound(s), and consequently, that it may have applications as a potent cosmeceutical material.

• Journal of the Korean Ceramic Society
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• v.34 no.11
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• pp.1159-1164
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• 1997

Magnetite(Fe3O4) powders were synthesized through glycothermal reaction by using crystalline $\alpha$-FeOOH as precursor and ethyleanne glycol as solvent. The phase, morphology and particle size of synthesized powders were characterized by XRD and an SEM. When only ethylene glycol was used as solvent, the phase was transformed from $\alpha$-FeOOH to $\alpha$-Fe2O3 and finally Fe3O4 at 27$0^{\circ}C$ for 6hr without morphological change. But by addition of water, Fe3O4 powders were synthesized at 23$0^{\circ}C$ for 3hr through solution-recrystalization process. As the content of water addition increased, the particle shape changed from sphere to octahedron and the partcle size increased. When the excess amount of water added, residual $\alpha$-FeOOH or $\alpha$-Fe2O3 was recrystalized.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1649-1652
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• 2006

2.22-inch qVGA $(240{\times}320)$ amorphous silicon thin film transistor liquid active matrix crystal display (${\alpha}$- Si TFT-AMLCD) panel has been successfully demonstrated employing a 2.5 um fine-patterning technology by a wet etch process. Higher resolution 2.22-inch qVGA LCD panel with an aperture ratio of 58% can be fabricated because the 2.5 um fine pattern formation technique is combined with high thermal photo-resist (PR) development. In addition, a novel concept of unique ${\alpha}$-Si TFT process architecture, which is advantageous in terms of reliability, was proposed in the fabrication of 2.22-inch qVGA LCD panel. Overall results show that the 2.5 um finepatterning is a considerably significant technology to obtain higher aperture ratio for higher resolution ${\alpha}$-Si TFT-LCD panel realization.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.366-371
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• 1995

High performance magnetic materials are characterized by the combination of outstanding magnetic properties and optimized microstructures, e.g., nanocrystalline composites of multilayers and small particle systems. The characteristic parameters of the hysteresis loops of these materials vary over more than a factor of $10^{6}$ with optimum values for the coercive field of several Tesla and permeabilities of $10^{6}$. Within the framework of the computational micromagnetism (nanomagnetism) using the finite element method the upper and lower bounds of the coercive field of different types of grain ensembles and multilayers have been determined. For the case of nanocrystalline composites the role of grain size, exchange and dipolar coupling between grains and the degree of grain alignment will be discusses in detail. It is shown that the largest coercivities are obtained for exchange decoupled grains, whereas remanence enhancing requires exchange coupled grains below 20 nm. For composite permanent magnets based on $Nd_{2}Fe_{14}B$ with an amount of ~ 50% soft $\alpha$-Fe-phase coercivities of ${\mu}_{0}H_{c}=0.75\;T$, a remanence of 1.5 T and an energy product of $400\;kJ/m^{3}$ is expected. In nanocrystalline systems the temperature dependence of the coercivity is well described by the relation ${\mu}_{0}H_{c}=(2\;K_{1}/M_{s}){\alpha}-N_{eff}{\mu}_{0}M_{s}$, where the microstructural parameters $\alpha$ and $N_{eff}$ take care of the short-range perturbations of the anisotropy and $N_{eff}$ is related to the long-range dipolar interactions. $N_{eff}$ is found to follow a logarithmic grain size size dependence ${\mu}_{0}H_{c}=(2\;K_{1}/M_{s}){\alpha}-N_{eff}(\beta1nD){\mu}_{0}M_{s}$. Several trends how to achieve the ideal situation $\alpha$->1 and $N_{eff}$->1->0 will be discussed.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.7
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• pp.352-357
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• 2004

The composites were fabricated, respectively, using 61vol.% SiC - 39vol.% TiB$_2$ and using 61vo1.% SiC - 39vo1.% WC powders with the liquid forming additives of 12wt% $Al_2$O$_3$＋Y$_2$O$_3$ by pressureless annealing at 180$0^{\circ}C$ for 4 hours. Reactions between SiC and transition metal TiB$_2$, WC were not observed in this microstructure. The result of phase analysis of composites by XRD revealed SiC(6H), TiB$_2$ and YAG(Al$_{5}$Y$_3$O$_{12}$) crystal phase on the SiC-TiB$_2$, and SiC(2H), WC and YAG(Al$_{5}$Y$_3$O$_{12}$) crystal phase on the SiC-WC composites. $\beta$\$\longrightarrow$$\alpha$-SiC phase transformation was ocurred on the SiC-TiB$_2$, but $\alpha$\$\longrightarrow$$\beta$-SiC reverse transformation was not occurred on the SiC-WC composites. The relative density, the vicker's hardness, the flexural strength and the fracture toughness showed respectively value of 96.2%, 13.34GPa, 310.19Mpa and 5.53Mpaㆍml/2 in SiC-WC composites. The electrical resistivity of the SiC-TiB$_2$ and the SiC-WC composites is all positive temperature coefficient resistance(PTCR) in the temperature ranges from $25^{\circ}C$ to 50$0^{\circ}C$. 2.64${\times}$10-2/$^{\circ}C$ of PTCR of SiC-WC was higher than 1.645${\times}$10-3/$^{\circ}C$ of SiC-TiB$_2$ composites.posites.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5667-5672
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• 2014

Folate receptor alpha ($FR{\alpha}$) mediates folate uptake by endocytosis, and while folate is essential to DNA methylation and synthesis and may have an important role in proliferating cells. $FR{\alpha}$ is known to be expressed in rapidly proliferating cells, including many cancer cell lines, but there has been no systematic assessment of expression in cervical cancer cell lines. The aim of the present study was to evaluate the effects of $FR{\alpha}$ on proliferation and apoptosis of cervical cells and correlation mechanism. In this study, we investigated the biological function of $FR{\alpha}$ in Hela cells using RNA interference. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK8) assay, while cell cycling and apoptosis were assessed by flow cytometry, mRNA levels by real time-PCR and protein levels of $FR{\alpha}$, c-Fos and c-Jun by Western blotting. The results revealed that $FR{\alpha}$ was highly expressed in Hela cells and its silencing with a small interfering RNA (siRNA) inhibited cell proliferation and induced cell apoptosis, arresting the cell cycle in G0/G1 stages while decreasing the proportion in S and G2/M stages, and suppressed the expression levels of c-Fos and c-Jun. In conclusion, the results of this study indicated that $FR{\alpha}$ down-regulation might be capable of suppressing cervical cancer cell proliferation and promoting apoptosis. It suggested that $FR{\alpha}$ might be a novel therapeutic target for cervical cancer.

• BMB Reports
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• v.45 no.12
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• pp.724-729
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• 2012

In this study, we evaluated the anti-melanogenesis effects of Caffeoylserotonin (CaS) in B16 melanoma cells. Treatment with CaS reduced the melanin content and tyrosinase (TYR) activity in B16 melanoma cells in a dose-dependent manner. CaS inhibited the expression of melanogenesis-related proteins, including microphthalmia-associated transcription factor (MITF), TYR, and tyrosinase-related protein-1 (TRP-1), but not TRP-2. ${\alpha}$-MSH is known to interact with melanocortin 1 receptor (MC1R) thus activating adenylyl cyclase and increasing intracellular cyclic AMP (cAMP) levels. Furthermore, cAMP activates extracellular signal-regulated kinase 2 (ERK2) via phosphorylation, which phosphorylates MITF, thereby targeting the transcription factor to proteasomes for degradation. The CaS reduced intracellular cAMP levels to unstimulated levels and activated ERK phosphorylation within 30 min. The ERK inhibitor PD98059 abrogated the suppressive effect of CaS on ${\alpha}$-MSH-induced melanogenesis. Based on this study, the inhibitory effects of CaS on melanogenesis are derived from the downregulation of MITF signaling via the inhibition of intracellular cAMP levels, as well as acceleration of ERK activation.

• Journal of the Korean Chemical Society
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• v.36 no.4
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• pp.536-539
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• 1992

Eight-membered ring spiro orthocarbonate (C$_{25}H_{20}O_4$, M$_r$ = 384) is monoclinic, space group C2/c, with a = 15.319(4), b = 9.057(3), c = 13.168(3)${\AA}$, ${\beta}$ = 98.53(3)$^{\circ}$, Z = 4, F(000) = 808, T = 290 K, ${\mu}$(Mo-K${\alpha}$) = 0.55 cm$_1$, D$_c$ = 1.36 g/cm$^3$ and D$_m$ = 1.40 g/cm$^3$. 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 direct methods and refined by full matrix least-squares methods. The final R value was 0.052 for 1412 observed reflections. The molecule has C$_2$point symmetry. The eight-membered ring has a chair conformation with pseudo-C$_s$ symmetry. The naphthyl ring is planar with the C-C bond lengths being in the range of 1.352∼1.444${\AA}$ and bond angles of 117.2∼123.5$^{\circ}$. The bond lengths of C(1)-C(9), C(8)-C(9) and C(9)-C(10) are somewhat longer than those of the other C-C bonds.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.203-207
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• 1999

V. alginolyticus 138-2, a marine halophilic bacterium, produced an extracellular amylase with a molecular weight of ca. 56,000. The analysis of the digestion products of soluble starch by thin layer chromatography(TLC) revealed that the extracellular amylase of V. alginolyticus 138-2 is a saccharifying-type alpha-amylase. The alpha-amylase activity of the culture supernatant of soluble starch was optimal at pH 6.0 and 45$^{\circ}C$. Ca2+ slightly increased the alpha-amylase activity, whereas Hg2+, An2+, Cu2+, Ni2+, Fe2+, and Mn2+inhibited the enzymatic activity. Alkylating thiol group agent, iodoacetic acid did not affect the alpha-amylase activity, but reduced thiol reagents such as dithiothreitol, cysteine, and beta-mercaptoethanol stimulated theenzymatic activity. On the other hand, even if V. alginolyticus 138-2 is a marine halophilic bacterium, its alpha-amylase activity was significantly inhibited by NaCl.