• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.231-235
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• 2005

Histamine-releasing factors (HRFs) are soluble mediators that can release histamine and other mediators from basophils and mast cells and their activity can vary, depending on the type of IgE. The activity of HRFs is affected by the presence of IgE, although HRF is thought to bind to a specific receptor other than IgE. Until now, HRF signaling pathway including its receptor remains unclear in spite of numerous studies. Since there had been many reports about reactive oxygen species (ROS) as a signaling molecule rather than as a by-product of metabolism, we investigated the possibility of ROS as an intracellular messenger involved in HRF-mediated histamine degranulation. In RBL-2H3 cells, ROS was generated by HRF using $H_2O_2$-sensitive fluorescence of fluorescent 2', 7'-dichlorofluorescein ($H_2DCFDA$). These effects were blocked by anti-oxidant N-acetylcysteine (NAC). These results suggest that ROS generation could play a role as an intracellular messenger in histamine release by HRF.

• Journal of the Korean Statistical Society
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• v.29 no.1
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• pp.95-108
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• 2000

Consider the oblique factor model X=Af＋$\varepsilon$, with defining relation $\Sigma$=Λ$\Phi$Λ'＋Ψ. This paper is concerned with suggesting an optimal Bayes criterion for determining the number of factors in the model, i.e. dimension of the vector f. The use of marginal likelihood as a method for calculating posterior probability of each model with given dimension is developed under a generalized conjugate prior. Then based on an appropriate loss function, a Bayes rule is developed by use of the posterior probabilities. It is shown that the approach is straightforward to specify distributionally and to imploement computationally, with output readily adopted for constructing required cirterion.

• Journal of the Korean Mathematical Society
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• v.32 no.2
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• pp.183-193
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• 1995

Let N be a $II_1$ factor and G be a finite group acting outerly on N. Then the crossed product algebra $M = N \rtimes G$ is also a $II_1$ factor and $N' \cap M = CI$, i.e. N is irreducible in M. Moreover, N is regular in M, in other words, M is generated by the normalizer $N_M (N)$.

• Nuclear Engineering and Technology
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• v.47 no.1
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• pp.135-138
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• 2015

A new correlation predicting the idealized critical mass-flow rates of water for subcooled and saturated liquid water including two-phase water flow was developed for a wide range of upstream stagnation pressures (e.g., 0.5-20.0 MPa). A choking correction factor dependent on the upstream stagnation pressure and subcooled temperature was introduced into a new correlation, and its values were suggested to satisfy the idealized nozzle data within 10% error ranges. The suggested correlation will be instructive and helpful for related studies and/or engineering works.

• Journal of the Korean Data and Information Science Society
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• v.16 no.2
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• pp.301-311
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• 2005

This study has conducted to measure the internet banking customer satisfaction using structured equation model. Data was collected by e-mail system. Among survey panel who had experience of using Hanwha-Bank internet banking service, final samples were 2,848 respondents. The results showed that usage convenience and economy factor was most correlated with customer satisfaction. And we found that word-of-mouth behavior was affected customer satisfaction.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.107-109
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• 1995

This paper considers backing structure of non-contact steel plate using magnectically levitation and aspect-quality factor is defined by estimation of electromagnet-aspect attraction steel plate. Characteristics of attraction power is studied in cylindrical electromagnet, U-type electromagnet, E-type electromagnet by aspect-quality factor. Designing and manufacturing electromagnet attraction steel plate, propriety of experimental results is confirmed.

• Transactions on Electrical and Electronic Materials
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• v.16 no.3
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• pp.151-155
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• 2015

We fabricated the Cu Schottky contact on an n-type Ge wafer and investigated the forward bias current-voltage (I-V) characteristics in the temperature range of 100~300 K. The zero bias barrier height and ideality factor were determined based on the thermionic emission (TE) model. The barrier height increased and the ideality factor decreased with increasing temperature. Such temperature dependence of the barrier height and the ideality factor was associated with spatially inhomogeneous Schottky barriers. A notable deviation from the theoretical Richardson constant (140.0 Acm^-2K^-2 for n-Ge) on the conventional Richardson plot was alleviated by using the modified Richardson plot, which yielded the Richardson constant of 392.5 Acm^-2K^-2. Finally, we applied the theory of space-charge-limitedcurrent (SCLC) transport to the high forward bias region to find the density of localized defect states (N_t), which was determined to be 1.46 × 10¹² eV^-1cm^-3.

• Korean Journal of Pharmacognosy
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• v.31 no.2
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• pp.168-173
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• 2000

Two diterpenes and one new sucrose isovaleryl ester having inhibitory effects on melanogenesis in B16 mouse melanoma were isolated from Euphorbiae Lathyridis Semen which has been used in traditional medicine for cancer, tumors and warts. New sucrose isovaleryl ester was identified as ${\alpha}-D-glucopyranoside$, $3,4,6-tris-O-(3-methyl-l-oxobutyl)-{\beta}-D-fructofuranosyl$, 2,6-bis(3-methylbutanoate) and two diterpenes were identified as ingenol-20-palmitate and 5,10-diacetyl-3-benzoyllathyrol$(Euphorbia\;factor\;L_3)$ from their spectral data.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.287-294
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• 2014

The transcription factor E2F1 is active during G1 to S transition and is involved in the cell cycle and progression. A recent study reported that increased E2F1 is associated with DNA damage and tumor development in several tissues using transgenic models. Here, we show that E2F1 expression is regulated by tristetraprolin (TTP) in prostate cancer. Overexpression of TTP decreased the stability of E2F1 mRNA and the expression level of E2F1. In contrast, inhibition of TTP using siRNA increased the E2F1 expression. E2F1 mRNA contains three AREs within the 3'UTR, and TTP destabilized a luciferase mRNA that contained the E2F1 mRNA 3'UTR. Analyses of point mutants of the E2F1 mRNA 3'UTR demonstrated that ARE2 was mostly responsible for the TTP-mediated destabilization of E2F1 mRNA. RNA EMSA revealed that TTP binds directly to the E2F1 mRNA 3'UTR of ARE2. Moreover, treatment with siRNA against TTP increased the proliferation of PC3 human prostate cancer cells. Taken together, these results demonstrate that E2F1 mRNA is a physiological target of TTP and suggests that TTP controls proliferation as well as migration and invasion through the regulation of E2F1 mRNA stability.

• Journal of Microbiology and Biotechnology
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• v.8 no.4
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• pp.378-387
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• 1998

The DNA sequence immediately following the xynA gene of Bacillus stearothermophilus 236 ［about l-kb region downstream from the translational termination codon (TAA) of the xynA gene］was found to have an ability to enhance the xylanase activity of the upstream xynA gene. An 849-bp ORF was identified in the downstream region, and the ORF was confirmed to encode a novel protein of 283 amino acids designated as XaiF (xylanase-activity-increasing factor). From the nucleotide sequence of the xaiF gene, the molecular mass and pI of XaiF were deduced to be 32,006 Da and 4.46, respectively. XaiF was overproduced in the E. coli cells from the cloned xaiF gene by using the T7 expression system. The transcriptional initiation site was determined by primer extension analysis and the putative promoter and ribosome binding regions were also identified. Blast search showed that the xaiF and its protein product had no homology with any gene nor any protein reported so far. Also, in B. subtilis, the xaiF trans-activated the xylanase activity at the same rate as in E. coli. In contrast, xaiF had no activating effect on the co-expressed ${\beta}-xylosidase$ of the xylA gene derived from the same strain of B. stearothermophilus. In addition, the intracellular and extracellular fractions from the E. coli cells carrying the plasmid-borne xaiF gene did not increase the isolated xylanase activity, indicating that the protein-protein interaction between XynA and XaiF was not a causative event for the xylanase activating effect of the xaiF gene.