• Archives of Pharmacal Research
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• v.29 no.1
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• pp.40-45
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• 2006

Several diacetoxy acetal analogues have been synthesized from santonin and assessed for their ability of inducing or enhancing the differentiation of human HL-60 leukemia cells. The compounds themselves had little effect on HL-60 cell differentiation. However, three analogues, 2a, 3a, and 5b, synergistically enhanced 1,25-dihydroxyvitamin $D_3[1,25-(OH)_2D_3]-induced$ HL-60 cell differentiation when combined with 5 nM of dihydroxyvitamin $D_3[1,25(OH)_2O_3]$, a well-known differentiation inducer. Especially, the compound 5b profoundly enhanced the $1,25-(OH)2O_3]-induced$ HL-60 cell differentiation.

• Journal of the Korean Electrochemical Society
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• v.23 no.3
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• pp.57-65
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• 2020

It is crucial to investigate the thermal degradation of lithium-ion batteries (LIBs) to understand the possible malfunction at high temperature. Herein, we investigated the effects of surface film formation on the thermal degradation of lithium cobalt oxide (LiCoO₂, LCO) cathode that is one of representative cathode materials. Cycling test at 60℃ exhibited poorer cycleability compared with the cycling at 25℃. Cathodes after the initial 5 cycles at 60℃ (60-LCO) exhibited higher impedance compared to the cathode after initial 5 cycles at 25℃ (25-LCO), resulting in the lower rate capability upon subsequent cycling at 25℃, although the capacity values were similar at the lowest C-rate of 0.1C. In order to understand degradation of the LCO cathode at the high temperature, we analyzed the cathodes surface using X-ray photoelectron spectroscopy (XPS). Among various peaks, intensity of lithium hydroxide (LiOH) increased substantially after the operation at 60℃, and the C-C signal that represents the conductive agent was distinctly lower on 60-LCO compared to 25-LCO. These results pointed to an excessive formation of cathode-electrolyte interphase including LiOH at 60℃, leading to the increase in the resistance and the resultant degradation in the electrochemical performances.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.4
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• pp.155-161
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• 2007

In order to characterize the role of sympathetic activity in obesity, we repeatedly assessed sympathetic activity via power spectral analyses of heart rate variability in the same subjects at 7, 11, 25, and 60 weeks, using monosodium glutamate (MSG)-induced obese and control rats. The effects of lower sympathetic activity on obesity were also evaluated. Fat mass in MSG rats was already higher at 7 weeks, but the sympathetic activity did not differ between 7 and 25 weeks. Between 25 and 60 weeks, the increase in fat mass, food efficiency, and body weight gain was higher in MSG rats. The increase in sympathetic activity between 25 and 60 weeks and sympathetic activity at 60 weeks were lower in MSG rats. Fat mass at 60 weeks was inversely correlated with changes in sympathetic activity between 25 and 60 weeks. Reduced plasma epinephrine levels by bilateral adrenal demedullation induced increase of fat mass. In, an attenuated increase of sympathetic activity with age may partly be responsible for aggravated obesity in MSG rats. Additionally, reduced sympathetic activity per se induced obesity in rats. These results suggest that lower sympathetic activity contributes to obesity in rats.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.657-663
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• 2012

To evaluate effects of water temperatures on nutrient releases of submerged plants in lake reservoir, COD, T-N and T-P releases of submerged plants were investigated for 60 days under different incubation temperatures ($5^{\circ}C$ and $25^{\circ}C$) in columns. The amounts of COD releases by Carex dimorpholepis were $60.4mg\;L^{-1}$ at $5^{\circ}C$ and $78.0mg\;L^{-1}$ at $25^{\circ}C$. In Miscanthus sacchariflorus, the amounts of COD releases were $62.5mg\;L^{-1}$ at $5^{\circ}C$ and $70.5mg\;L^{-1}$ at $25^{\circ}C$. The amounts of T-N releases in Carex dimorpholepis at $5^{\circ}C$ and $25^{\circ}C$ were 45.8 and $60mg\;L^{-1}$, respectively. In Miscanthus sacchariflorus, the amounts of T-N releases were $55.7mg\;L^{-1}$ at $5^{\circ}C$ and $61.0mg\;L^{-1}$ at $25^{\circ}C$. At $5^{\circ}C$, the amounts of T-P releases in Carex dimorpholepis and Miscanthus sacchariflorus were 5.65 and $7.10mg\;L^{-1}$, respectively. At $25^{\circ}C$, the amounts of T-P releases in Carex dimorpholepis and Miscanthus sacchariflorus were 8.70 and $8.18mg\;L^{-1}$, respectively. In the column experiment, the amounts of COD, T-N and T-P releases by submerged plants at $25^{\circ}C$ were generally higher than those at $5^{\circ}C$.

• Textile Coloration and Finishing
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• v.25 no.3
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• pp.232-239
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• 2013

In this study, 25gsm melt-blown polypropylene nonwoven for dust-proof/medical masks was finished by the corona discharging treatment. The influence of corona discharging parameters on the filtration efficiency was investigated. Several parameters such as discharging voltage, discharging speed, distance to discharging wire and configuration of discharging system had an effect on filtration efficiency, while the parameters had no effect on breathing resistance. Optimum corona discharging conditions are as follows: Wires were installed on the upper part of the nonwoven and paper pipe was installed on the lower part of the nonwoven having a distance of 5cm. The sequence of wire voltages was +60 kV, +60 kV, 0, -60 kV, and -60 kV. The discharging voltage and speed were 60 kV and 30m/min respectively. The nonwoven treated by corona discharging at the optimum condition showed a filtration efficiency of 80% or more, which is suitable for dust-proof/medical masks.

• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.219-225
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• 2004

This study was conducted to evaluate growth and yield characteristics and the contribution to the yield according to the emergent sequence of tiller under two planting density $(60{\times}15\;cm,\;60{\times}25\;cm)$ in Coix lachryma-jobi L. var. mayuen Stapf. The average culm length and number of rachillas of $60{\times}25\;cm$ planting density were 20 cm shorter and 4.7 higher, respectively, whereas seed setting position of $60{\times}25\;cm$ planting density was 1.7 nodes lower compared with $60{\times}15\;cm$ planting density. Culm length and culm diameter of each tiller became shorter and thinner as the tiller emerged later. Length of rachillas was longer, number of grains was higher and ripening rate was also higher in $60{\times}25\;cm$ planting density than those of $60{\times}15\;cm$ planting density, whereas 100 grain weight in $60{\times}25\;cm$ planting density was lower by 0.5 g compared with $60{\times}15\;cm$ planting density. Length of rachillas and number of grains according to the emergent sequence of tiller were shown shorter and lower as the tiller emerged later. The highest number of bract was obtained from the main culm in both planting densities. 100 grain weight according to the emergent sequence of tiller became lower as the tiller emerged later in $60{\times}15\;cm$ planting density, but there was no clear tendency in $60{\times}25\;cm$ planting density. Among 8 tillers, 5th tiller and 4th tiller of main culm contributed 84.4% to the yield in $60{\times}15\;cm$ planting density, while it was 84.1% in $60{\times}25\;cm$ planting density. Analysis of path coefficient to grain yield showed that direct effect was the highest in the number of grain per tiller followed by in the 100 grain weight and in ripening rate.

• Journal of applied mathematics & informatics
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• v.1 no.1
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• pp.1-12
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• 1994

We consider a single channel CSMA/CD system with D homogeneous stations and impeded buffer of infinite size. We find a sufficient condition for the model to be stable under the threshold control policy and derive the limiting distri-bution of the number of messages in the system at the moment of service completion. We also derive the limiting distributing of the number of messages in the system size at arbitrary time by using Markov regenerative processes. Some numerical examples and special cases are also treated.

• Journal of the Korean Society of Food Culture
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• v.19 no.1
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• pp.94-105
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• 2004

The biochemical components of Namcheondlggae, Miryangdlkkae 25, Boradlggae and Ipdlkkae 1 were measured. The samples were extracted with hot water, 60% acetone or 80% ethanol for screening physiological activity. The crude protein content (4.36%) was found in the Miryangdlkkae 25 and calcium content (497.5 mg%) was found in the Namcheondlggae among the tested 4 perilla loaves. Fructose was 30.86 mg% in the Namcheondlggae and free amino acids at all perilla leaves was detected seventeen. In Boradlggae, glutamic acid and alanine were 25.37 and 11.91 mg%. Totally nine non-volatile organic acids were also detected and the contents of malic acid and glutaric acid were 28.34 and 14.57 mg% in Boradlggae. The Miryangdlkkae 25 had the highest vitamin C amount which was 113.24 mg%. Angiotensin converting enzyme (ACE) inhibition activity of 60% acetone extract of Miryangdlkkae 25 was 39.20% when added as addition of 200 ppm level and xanthine oxidase inhibition activity of 80% ethanol extract of Boradlggae was 46.71%. Electron denoting activity of 60% acetone extract from Namcheohndlggae was the strongest inhibition activity as 98.19% when 200 ppm level of the sample extracts were added.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.19-25
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• 1996

A fundamental study on composting garbage was performed in a laboratory scale of a high-speed composting reactor. Major parameters were moisture content, temperature and C/N ratio. The results are as follows; pH of the compost was the highest at moisture 60% and anaerobic condition occurred at 70%. It was, also, found that C/N ratio, caused a nitrogen loss due to an occurrence of plentiful $NH_3$. Under controlling Temperature, pH was the highest at $60^{\circ}C$ and an inverse effect for Composting occurred under excessive Temperature as pH at $70^{\circ}C$ was lower than that of soil. The variation of pH and C/N ratio was the lowest when C/N ratio was 25. The results obtained from composting garbage revealed that the best condition of composting occurred under 50 to 60% of moisture content, $60^{\circ}C$ of temperature, and 25 of C/N ratio. It is believed that composting may be finished with in 56 hours if an optimal condition is setting up.

• Journal of Pharmaceutical Investigation
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• v.33 no.1
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• pp.1-5
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• 2003

Physicochemical changes of poloxamer-based gel containing capsaicin analog (N-[3-(3,4-dimethylphenyl)propyl]-4-(2-aminoethoxy)-3-methoxyphenyl acetamide) such as drug content, viscosity and surface tension were investigated during the storage conditions at three different temperatures (25, 40 and $60^{\circ}C$) over 90 days. No noticeable changes of color were observed when stored at 25 and $40^{\circ}C$. However, the color of white poloxamer gels turned yellow during storage at $60^{\circ}C$. The drug contents were unchanged during storage at $25^{\circ}C$ but had tendency to decrease at $40^{\circ}C$. The drug contents were highly decreased over 40-50% when stored at $60^{\circ}C$. The viscosity of a poloxamer-based gel was unchanged during storage at 25 and $40^{\circ}C$ but greatly increased at $60^{\circ}C$. The surface tension of a poloxamer-based gel was not changed at three different temperatures. The storage conditions of a poloxamer-based gel containing capsaicin analog can be considered for further clinical applications.