• Journal of Life Science
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• v.13 no.3
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• pp.241-247
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• 2003

While the DNA-protein kinase (DNA-PK) complex, comprised of DNA-PKcs and Ku80, is primary involved in the repair of DNA double-strand breaks, it is also believed to participate in additional cellular processes. Here, treatment of embryo fibroblasts (MEFs) derived from either wild-type (Wt) or DNA-PKcs-null (DNA-$PKcs^{-/-}$) mice with various stress inducing agents revealed that adriamycin was markedly more cytotoxic for $Ku80^{-/-}MEFs$ and led to their long-term accumulation in the $G_2$/M phase. This differential response was not due to differences in DNA repair, since adrimycin-triggered DNA damage was repaired with comparable efficiency in both Wt and $Ku80^{-/-}MEFs$, but was associated with differences in the expression of important cell cycle regulatory genes. Our results support the notion that Ku80-mediated cytoprotection and $G_2$/M-progression are not only dependent on the cell's DNA repair but also may reflect Ku80's influence on additional cellular processes such as gene expression.

• Journal of Animal Science and Technology
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• v.58 no.10
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• pp.37.1-37.10
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• 2016

Background: Providing of insufficient nutrients limits the potential growth of pig, while feeding of excessive nutrients increases the economic loss and causes environment pollution. For these reasons, phase feeding had been introduced in swine farm for improving animal production. This experiment was conducted to evaluate the effects of dietary energy levels and phase feeding by protein levels on growth performance, blood profiles and carcass characteristics in growing-finishing pigs. Methods: A total of 128 growing pigs ([Yorkshire ${\times}$ Landrace] ${\times}$ Duroc), averaging $26.62{\pm}3.07kg$ body weight, were assigned in a $2{\times}4$ factorial arrangement with 4 pigs per pen. The first factor was two dietary energy level (3,265 kcal of ME/kg or 3,365 kcal of ME/kg), and the second factor was four different levels of dietary protein by phase feeding (1growing(G)-2finishing(F) phases, 2G-2F phases, 2G-3F phases and 2G-3F phases with low CP requirement). Results: In feeding trial, there was no significant difference in growth performance. The BUN concentration was decreased as dietary protein level decreased in 6 week and blood creatinine was increased in 13 week when pigs were fed diets with different dietary energy level. The digestibility of crude fat was improved as dietary energy levels increased and excretion of urinary nitrogen was reduced when low protein diet was provided. Chemical compositions of longissimus muscle were not affected by dietary treatments. In backfat thickness ($P_2$) at 13 week, pigs fed high energy diet had thicker backfat thickness (P = 0.06) and pigs fed low protein diet showed the trend of backfat thinness reduction (P = 0.09). In addition, water holding capacity was decreased (P = 0.01) and cooking loss was increased (P = 0.07) as dietary protein level reduced. When pigs were fed high energy diet with low subdivision of phase feeding, days to 120 kg market weight was reached earlier compared to other treatments. Conclusion: Feeding the low energy diet and subdivision of growing-finishing phase by dietary protein levels had no significant effect on growth performance and carcass characteristics. Also, phase feeding with low energy and low protein diet had no negative effects on growth performance, carcass characteristics but economical profits was improved.

• Journal of the Korean Electrochemical Society
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• v.4 no.4
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• pp.146-151
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• 2001

The Frumkin adsorption isotherm of the over-potentially deposited hydrogen (OPD H) for the cathodic $H_2$ evolution reaction (HER) at the poly-Ni|0.05M KOH aqueous electrolyte interface has been studied using the phase-shift method. The behavior of the phase shift $(0^{\circ}\leq{\phi}\leq90^{\circ})$ for the optimum intermediate frequency corresponds well to that of the fractional surface coverage $(1\geq{\theta}\geq0)$ at the interface. The phase-shift method, i.e., the Phase-shift profile $(-{\phi}\;vs.\;E)$ for the optimum intermediate frequency, can be used as a new method to estimate the Frumkin adsorption isotherm $(\theta\;vs.\;E)$ of the OPD H for the cathodic HER at the interface. At the poly-Ni|0.05M KOH aqueous electrolyte interface, the rate (r) of change of the standard free energy of the OPD H with $\theta$, the interaction parameter (g) for the Frumkin adsorption isotherm, the equilibrium constant (K) for the OPD H with $\theta$, and the standard free energy $({\Delta}G_{\theta})$ of the OPD H with ${\theta}$ are $24.8kJ mol^{-1},\;10,\;5.9\times10^{-6}{\leq}K{\leq}0.13,\;and\;5.1\leq{\Delta}G_{\theta}\leq29.8kJ\;mol^{-1}$. The electrode kinetic parameters $(r,\;g,\;K,\;{\Delta}G_{\theta})$ depend strongly on ${\theta} (0{\leq}{\theta}{\leq}1)$.

• Natural Product Sciences
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• v.19 no.2
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• pp.145-149
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• 2013

A simple reversed phase HPLC method was established for quantitative determination of liquiritigenin (1), genistein (2), isoliquiritigenin (3), and 7-hydroxyflavanone (4) from stems of Spatholobus suberectus Dunn (Leguminosae) using a binary gradient of $H_2O$ and MeOH as a mobile phase with UV detection at 280 nm. All calibration curves showed good linear regression ($r^2$ > 0.998) within test ranges. The detection limits of the four compounds were $0.43{\sim}1.63{\mu}g/mL$. The contents of four flavonoids (1 - 4) from the stem of S. suberectus were 6.54 mg/g, 1.66 mg/g, 6.65 mg/g, and 1.93 mg/g, respectively.

• Journal of Animal Environmental Science
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• v.4 no.2
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• pp.167-174
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• 1998

It is known that the anaerobic fermentation of organic matter (OM) is divided into 2 phases, acidogenic phase in which OM is digested into volatile fatty acid (VFA), and methanogenic phase where the produced VFA is converted to CH4 and CO2. In a natural fermenting procedure, these 2 phases occur at the same time. However the total production of end products (methane) may be limited if these 2 phases occur at the same time. This is believed to be due to the difference in growth rate, substrate-utilizing efficiency and favorable environment for each microbes (acidogens and methanogens), involved in each phase. It is therefore suggested for the maximum recycling of organic waste (such as animal waste) through providing 2 different steps in fermenting procedure, acidogenic phase and methanogenic phase, in each case the activity of involved microbes can be maintained at the maximum level. The results obtained from these experiments are summarized as follows : The loading rates of swine waste were made through 2.5, 5 and 10 gVS / l / d to identify its acidogenic fermenting character in this study. The VFA yield was maximized at 10 gVS / l / d of loading rate. On the basis of this study was executed to identify the optimum HRT of 1, 2 and 4 days at 10 gVS / l / d of loading rate in acidogenic phase. The maximum VFA yield was obtained at 1 days of HRT.

• Journal of Power Electronics
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• v.14 no.3
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• pp.458-467
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• 2014

In this paper, a single-phase current-source bidirectional converter topology for V2G applications is proposed. The proposed converter consists of a single-phase current-source rectifier (SCSR) and an auxiliary switching network (ASN). It offers bidirectional power flow between the battery and the grid in the buck or boost mode and expands the output voltage range, so that it can be compatible with different voltage levels. The topology structure and operating principles of the proposed converter are analyzed in detail. An indirect control algorithm is used to realize the charging and discharging of the battery. Finally, the semiconductor losses and system efficiency are analyzed. Simulation and experimental results demonstrate the validity and effectiveness of the proposed topology.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.3
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• pp.11-18
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• 1991

Volatile organic compounds(VOC) present in or generated by many sources, can be toxic, mutagenic or even carcinogenic, so that control of such emissions is significant. The 6 chlorinated organic chemicals as VOC were examined in this study. Prediction of the behavior of VOC on activated carbon beds is an important part of control system design. The objective of this study was to predict gas phase sorption isotherms from physical properties and liquid phase isotherms obtained with the same adsorbent and adsorbate. One of the techniques that was investigated was quantitative structure-activity relationships(QSAR) for the predicition procedures. It was possible to estimate sorption isotherms in the gas phase($a_g$) using either connectivity index, $^2{\chi}$, and the Henry's law coefficient ($H_a$) or the solubility and the equilibrium concentration in the gas phase. As a result of study, the predictive equation based on Freundlich model for $a_g$ was ${\log}\;a_g=0.238\;^2{\chi}+0.573\;{\log}\;H_a+4.330(r^2=0.94)$. Finally, this would provide a potentially useful tool to describe and predict sorption capacity without time-consuming tests.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.917-924
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• 2012

The conformational study of glycerol has been carried out using the M06-2X/cc-pVTZ level of theory in the gas phase and the SMD M06-2X/cc-pVTZ level of theory in water in order to understand its conformational preferences and solvation effects. Most of the preferred conformers of glycerol have two $C_5$ hydrogen bonds in the gas phase, as found by the analysis of calorimetric data. It has been known that the solvation drove the hydrogen bonds of glycerol to be weaker and its potential surface to be fatter and that glycerol exists as an ensemble of many feasible local minima in water. The calculated populations of glycerol in the gas phase and in water are consistent with the observed values, which are better than the previously calculated ones at the G2(MP2), CBS-QB3, and SM5.42 HF/6-31G(d) levels of theory.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.110-113
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• 2005

Under the condition of nutritional deprivation, actively growing cells prepare to enter $G_0$-like stationary phase. Protein modification by phosphorylation/dephosphorylation or ubiqutination contributes to transfer cells from active cell cycle to dormant stage. We show here that Psp1/Sds23, which functions in association with the 20S cyclosome/APC (1) and is essential for cell cycle progression in Schizosaccharomyces pombe (2), is phosphorylated by stress-activated MAP kinase Sty1 and protein kinase A, as well as Cdc2/cyclinB, upon entry into stationary phase. Three serines at the positions 18,333 and 391 are phosphorylated and overexpression of Psp1 mutated on these sites causes cell death in stationary phase. These modifications are required for the binding of Spufd2, a S.pombe homolog of multiubiquitin chain assembly factor E4 in ubiquitin fusion degradation pathway. Deletion of Spufd2 gene led to increase cell viability in stationary phase, indicating that S. pombe Ufd2 functions to inhibit cell growth at this stage to maintain cell viability. Moreover, Psp1 enhances the multiubiquitination function of Ufd2, suggesting that Psp1 phosphorylated by sty1 and PKA kinases is associated with the Ufd2-dependent protein degradation pathway, which is linked to stress tolerance, to maintain cell viability in the $G_0$-like stationary phase.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1129-1133
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• 2004

The effects of Pluronic F-68, a non-ionic surfactant, on the growth and physical characteristics of Digitalis lanata suspension cultures were investigated in aqueous two-phase systems (ATPSs) composed of $4.5\%$ polyethylene glycol (PEG) 20,000 and $2.8\%$ crude dextran. In the range of 0.1-10.0 g $1^{-1}$, Pluronic F-68 enhanced the maximum cell density in a medium with ATPSs, even though Pluronic F-68 did not affect cell growth in a normal growth medium. In terms of physical properties of ATPSs with cell suspension cultures, 0.2 g $1^{-1}$ of Pluronic F-68 reduced viscosity by up to $40\%$, while 0.1 g $1^{-1}$ of Pluronic F-68 significantly enhanced the oxygen transfer rate. In addition, we successfully performed aqueous two-phase cultivation in a 5-1 stirred tank bioreactor with 0.5 g $1^{-1}$ of Pluronic F-68, and discovered that cell growth in ATPSs was similar to that in normal growth medium.