• Communications for Statistical Applications and Methods
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• v.22 no.3
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• pp.277-283
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• 2015

Pickands constant $H_{\alpha}$ appears in the classical result about tail probabilities of the extremes of Gaussian processes and there exist several different representations of Pickands constant. However, the exact value of $H_{\alpha}$ is unknown except for two special Gaussian processes. Significant effort has been made to find numerical approximations of $H_{\alpha}$. In this paper, we attempt to compute numerically $H_{\alpha}$ based on its representation derived by $H{\ddot{u}}sler$ (1999) and Albin and Choi (2010). Our estimates are compared with the often quoted conjecture $H_{\alpha}=1/{\Gamma}(1/{\alpha})$ for 0 < ${\alpha}$ ${\leq}$ 2. This conjecture does not seem compatible with our simulation result for 1 < ${\alpha}$ < 2, which is also recently observed by Dieker and Yakir (2014) who devised a reliable algorithm to estimate these constants along with a detailed error analysis.

• Archives of Pharmacal Research
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• v.24 no.4
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• pp.338-341
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• 2001

Circadian variations of sulfamethoxazole pharmacokinetics were studied after a single oral administration of sulfamethoxazole, 50 mg/kg, to rabbits at 09:00 (a.m.) and 22 :00 (p.m.). The profiles of plasma sulfamethoxazole concentration showed from 6h to 24 h significant statistical difference (p<0.05) between 09:00 and 22:00. The half-life $t_{1/2} was significantly shorter in the morning (11.2 $\pm$3.2 h) when compared to the nighttime (15.4 $\pm$ 3.5h) (7< 0.05). The AUC was significantly decreased in the morning (1325 $\pm$ 264${u}g/ml$.h) than that in the nighttime (2059 $\pm$ 379${u}g/ml$. h) (p<0.05). Tota1 body clearance ($Cl_t$ was significantly higher when sulfamethoxazole was given in the morning (6.65 $\pm$ 0.23 ml/min) versus in the nighttime (4.28 $\pm$ 0.20 ml/min) (p<0.05).

• Child Health Nursing Research
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• v.23 no.3
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• pp.353-363
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• 2017

Purpose: Oral glucose and pH are known as critical indicators for the growth of microorganism inside the oral cavity. This study was performed to identify oral glucose and pH variances in the early postnatal days of newborns. Methods: An explorative study which included 67 newborns was conducted to measure the oral glucose and pH during the first three days of life. Oral secretions were collected every 8 hours for three days or 6 to 9 times immediately after birth up to discharge. Oral glucose and pH variances during the three days were analyzed using the SPSS 22.0. Results: Oral glucose was $30.66{\pm}22.01mg/dl$ at birth then increased to $54.77{\pm}27.96mg/dl$ at the third day of life (F=8.04, p<.001) while oral pH decreased from $7.35{\pm}0.36$ to $5.53{\pm}0.39$ during the three days (F=113.35, p<.001). Oral glucose and pH were related to gestational age, regurgitation, and maternal diabetic mellitus. A negative correlation was found between oral glucose and pH (r=-.34, p<.001). Conclusion: Oral glucose and pH can be utilized for oral health assessment in newborns. Further study is needed to explore the factors which influence oral glucose and pH in high-risk newborns.

• Journal of Fashion Business
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• v.22 no.1
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• pp.124-134
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• 2018

This study examined the dyeing characteristics and spectrum of cotton and silk by using dyeing solution extracted from aronia. The value $L^{\ast}$ which indicates the brightness of cotton regardless of mordant increases with increasing pH from pH 3.5 to pH 10.5. The color difference value(${\Delta}E$) of the cotton was generally high in pH 3.5 regardless of mordant existence. The silk showed the highest ${\Delta}E$ value in pH 3.5 dye solution as cotton did. On the other hand, the silk with mordant dyed showed the highest ${\Delta}E$ value in pH 7. Silk fabrics dyed with Aronia solution turns out red in pH 3.5, blue in pH 7 and yellow in pH 10.5. This is because of the amino acid, one of the silk ingredients, combines with a part of anthocyanin to show blue. As the result of the spectrum measurement, the maximum absorption wavelength of Aronia solution was increased in the order of pH 10.5, pH 3.5 and pH 7, regardless of extraction temperature and mordant. The measurement results of color fastness to washing and color fastness to light are generally low. Therefore, there is a need for further study to improve color fatness in the future.

• The Korea Journal of Herbology
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• v.39 no.4
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• pp.37-45
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• 2024

Objectives : This study aimed to elucidate antioxidant activity of chrysin in polyinosinic-polycytidylic acid (poly-IC) and lipoteichoic acid-induced RAW 264.7 mouse macrophages. Methods : RAW 264.7 co-stimulated with poly-IC and lipoteichoic acid were incubated with chrysin at concentrations of 25 and 50 µM. Hydrogen peroxide production was measured with dihydrorhodamine 123 assay. Nitric Oxide (NO) production was evaluated by griess reagent assay. Results : For 16 h, 18 h, 20 h, 22 h, and 24 h incubation, chrysin at the concentration of 25 and 50 µM significantly suppressed hydrogen peroxide production in poly-IC and lipoteichoic acid-induced RAW 264.7. In details, production of hydrogen peroxide in 'poly-IC and lipoteichoic acid'-stimulated RAW 264.7 treated for 16 h with chrysin at concentrations of 25 and 50 µM was 83.84% and 79.3% of the control group treated with poly-IC and lipoteichoic acid only, respectively; the production of hydrogen peroxide for 18 h was 84.36% and 79.93%, respectively; production of hydrogen peroxide for 20 h was 85.68% and 80.22%, respectively; production of hydrogen peroxide for 22 h was 85.81% and 79.95%, respectively; production of hydrogen peroxide for 24 h was 86.01% and 80.18%, respectively. Additionally, chrysin at the concentration of 5, 10, 25, and 50 µM significantly inhibited NO production in THP-1 human monocytic cell line. Conclusions : Chrysin might have anti-oxidative activity related to its inhibition of hydrogen peroxide production in 'poly-IC and lipoteichoic acid'-stimulated RAW 264.7.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.456-462
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• 1992

This study was performed to rapid fermentation from sardine hydrolyzate by using column reactor. The column reactor was constructed from three glass columns $(30cm{\times}5cm)$ and each column was packed with colloidal silica and sodium alginate (1:5) on which Pediococcus halophilus R-22, Saccharomyces rouxii R-60 and Candida etchellsii H-50, respectively, was previously fixed. At that time, optimal conditions for rapid fermentation were found the pH of 5.2, temperature of $30^{\circ}C$ and 10% NaCl. For rapid fermentation, immobilized whole cells of P. halophilus R-22, S. ruoxii R-60 and C. etchellsii H-50 packed the each column reactor were produced 0.75% lactic acid, 2.5% ethylalcohol and 18 mg/l 4-ethylguaiacol under the optimal conditions.

• Journal of The Korean Astronomical Society
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• v.48 no.6
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• pp.357-364
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• 2015

We observe ten known 22GHz H₂O maser galaxies during February 19-22, 2011 using the 21 m Tamna telescope of the Korean VLBI Network and a new wide-band digital spectrometer. Simultaneously we searched for 43GHz SiO v = 1, 2, J = 1-0 maser emission. We detect H₂O maser emission towards five sources (M 33, NGC 1052, NGC 1068, NGC 4258, M 82), with non-detections towards the remaining sources (UGC 3193, UGC 3789, Antennae H₂O-West, M 51, NGC 6323) likely due to sensitivity. Our 22GHz spectra are consistent with earlier findings. Our simultaneous 43GHz SiO maser search produced non-detections, yielding - for the first time - upper limits on the 43GHz SiO maser emission in these sources at a 3 σ sensitivity level of 0.018K-0.033K (0.24 Jy-0.44 Jy) in a 1.75 km s⁻¹ velocity resolution. Our findings suggest that any 43GHz SiO masers in these sources (some having starburst-associated H₂O kilomasers) must be faint compared to the 22GHz H₂O maser emission.

• Korean Chemical Engineering Research
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• v.44 no.2
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• pp.121-128
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• 2006

Propylene epoxidation by $H_2O_2$ (30％ aqueous) as oxidant was studied in a semi-batch reactor using TS-1 catalyst: Effects of reaction temperature, time, pressure, solvent, catalyst and $H_2O_2$ concentration on $H_2O_2$ conversion (limiting reagent) and product distribution were investigated. Potential inhibition by propylene oxide on the epoxidation rate was also examined. Ti-MCM-22 with MWW zeolytic structure was found to exhibit better performance than TS-1 with MFI structure, provide that a proper choice of solvent(acetonitrile) is made.

• Food Science and Preservation
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• v.19 no.2
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• pp.308-314
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• 2012

Two hundred and twenty three yeast strains were randomly isolated from Korean traditional $nuruk$. Among them, six urease producing yeast strains (designated JJA, JJB, JJ22, SHA, SHC and SH10) were selected on the Christensen urea agar plates. They showed the same pattern in the PCR-RFLP analysis of the ITS I-5.8S-ITS II region digested with $Hae$III and $HinF$1 restriction endonucleases. Its DNA sequences showed 100% (strains SHA, SHC and SH10) and 99.8% (strains JJA, JJB and JJ22) identity with those of $Issatchenkia$ $orientalis$ type strain ATCC 24210. Phylogenetic analysis resulted in that all the strains were closely related to $I.$ $orientalis$. Two representative strains, JJ22 and SH10, showing the highest urease activities were selected for further characterization. Their morphological, physiological and biochemical characteristics were also the same as $I.$ $orientalis$. Therefore, both the two strains were identified as $I.$ $orientalis$. They could grow at a wide range of temperature between $20-40^{\circ}C$ as well as pH between 2.0 and 10.0. However, a higher level urease activity were obtained at acidic pH than that at alkalic pH. The maximal level of urease activity was obtained at $30^{\circ}C$ (strain SH10) or $35^{\circ}C$ (strain JJ22) and in a liquid medium adjusted to the initial pH 5.0.

• Communications of the Korean Mathematical Society
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• v.22 no.1
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• pp.41-51
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• 2007

Let R be a ring with left identity e and suitably-restricted additive torsion, and Z(R) its center. Let H : $R{\times}R{\times}R{\rightarrow}R$ be a symmetric 3-additive mapping, and let h be the trace of H. In this paper we show that (i) if for each $x{\in}R$, $$n=<<\cdots,\;x>,\;\cdots,x>{\in}Z(R)$$ with $n\geq1$ fixed, then h is commuting on R. Moreover, h is of the form $$h(x)=\lambda_0x^3+\lambda_1(x)x^2+\lambda_2(x)x+\lambda_3(x)\;for\;all\;x{\in}R$$, where $\lambda_0\;{\in}\;Z(R)$, $\lambda_1\;:\;R{\rightarrow}R$ is an additive commuting mapping, $\lambda_2\;:\;R{\rightarrow}R$ is the commuting trace of a bi-additive mapping and the mapping $\lambda_3\;:\;R{\rightarrow}Z(R)$ is the trace of a symmetric 3-additive mapping; (ii) for each $x{\in}R$, either $n=0\;or\;<n,\;x^m>=0$ with $n\geq0,\;m\geq1$ fixed, then h = 0 on R, where denotes the product yx+xy and Z(R) is the center of R. We also present the conditions which implies commutativity in rings with identity as motivated by the above result.