• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.81-87
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• 2005

This study was performed to investigate the antimicrobial activities of the Plagiorhegama dubium extracts against food-borne pathogens. The methanol extract was partitioned into petroleum ether, chloroform, ethyl acetate, and methanol portions. The antimicrobial activity of the P. dubium extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The methanol extracts of P. dubium showed the highest antimicrobial activity against Staphylococcus aureus and Escherichia coli. The synergistic effect has been found in combined extracts of P. dubium and Hedyotis diffsa as compared to each extracts alone. Finally, the growth inhibition curve was determined using methanol extracts of P. dubium against S. aureus and E. coli. The methanol extract of P. dubium showed strong antimicrobial activity against S. aureus at the concentration of 4,000 ppm. The 4,000 ppm of ethyl acetate portion from P. dubium retarded the growth of S. aureus more than 36 hours and E. coli up to 60 hours. The methanol extracts of P. dubium has been shown the antimicrobial activity against S. aureus and E. coli.

• Nuclear Engineering and Technology
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• v.14 no.4
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• pp.172-177
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• 1982

The state of Am in the concentration of 10$^{-5}$M has been studied in the pH range of 5 to 10 by filtration and centrifugation method. By the experiments, we could estimate possible Am hydrolysis products and solubility constants. If the solubility of Am (OH)$_3$ estimated by Baes and Mesmer is increased about a factor of 10, i.e. changing logk=-l8.7 to logk=-17 5 it was found that the calculated curve of Am concentration versus pH agreed completely with experimental values.

• The Korean Journal of Ecology
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• v.19 no.2
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• pp.151-163
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• 1996

To investigate the early symptoms of light-chilling, alterations of chlorophyll fluorescence transients were monitored in cucumber (Cucumis sativus L. cv. Ilmichungjang) leaves. During 24 h chilling, decreases in (Fv)m/Fm, qE and qQ, and an increase in Fo were observed. The chilling effects were not recovered at room temperature, and a significant increase in Fo was observed during the recovery period. After 6 h chilling, ‘dip’(D) level of the transients became obscure, and the negative slope after ‘peak’(P) disappeared. The first derivative (dFv/dt) of the fast fluorescence rise curve was used to obtain more accurate information about the changes in the transients. The maximal rate of the fluorescence increase in the D-p rise curve (Fr) has been the most frequently used chilling stress indicator. However, a correct value of Fr could not be measured when the D level became obscure. This problem was overcome by introducing a new indicator, HFr (dFv/dt at Fv = 1/2 (Fv)m), and HFr gave very similar values to Fr. To monitor the changes in curvature around D level, another new parameter, ${\Delta}S$(D-Fr), was also introduced. These three parameters decreased very sensitively during light-chilling. In addition, increases in these parameters were observed during the first 2 h chilling, but this increase in Fr was also observed in pea leaf discs dark-chilled for 15 min, suggesting that this very early change is a common response to chilling in both pea and cucumber leaves. Quenching coefficients were also very sensitive to chilling, especially qE. Discussion on the usage of these parameters as chilling stress indicators is given in the text.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.157-161
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• 2000

The Eye sensitivity in the difference conditions of a light source intensity consists of two functions by the receptor of cone and rod according to a wavelength. We derived a distribution function of $P({\lambda})=A{\cdot}e^{-({\lambda}-{\lambda}_0)^2/2W^2}$ using a respond probability of the receptor of cone-rod for a photon. It was well applied for a CIE eye's sensitivity curve of a wavelength, we obtained values in case of a relative sensitivity. A = 106.4, ${\lambda}_0=559.2$, W = 83.5 for a photopic and A = 99.3 ${\lambda}_0=502.6$, W = 79.5 for a scotopic, and in case of a sensitivity curve using 1m/W units. $A=7.2{\times}10^4$, ${\lambda}_0=559.2$, W = 83.5 for a photopic and $A=1.6{\times}10^5$, ${\lambda}_0=502.6$. W = 79.5 for a scotopic.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.41.3-42
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• 2016

New CCD photometric observations of GX Aur have been made between 2004 and 2015. Our light curves are the first ever compiled and display the variable O'Connell effect. The light variations are satisfactorily modeled by including time-varying cool-spots on the component stars. Our light curve synthesis indicates that the eclipsing pair is an A-type contact binary with parameters of i = 81.1 deg, ${\Delta}T=36K$, q = 0.950 and f = 46%. Including our 25 timing measurements, a total of 83 times of minimum light spanning about 66 yr were used for a period study. It was found that the orbital period of GX Aur has varied due to two periodic oscillations superposed on an upward-opening parabolic variation. The long-term period increase rate is deduced as $+9.636{\times}10^{-10}d\;yr^{-1}$, which can be produced as a mass transfer from the secondary star to the primary at a rate of $3.136{\times}10^{-6}M_{\odot}\;yr^{-1}$, among the largest rates for contact systems. The periods and semi-amplitudes of the two periodic variations are about $P_3=8.7yr$ and $P_4=21.2yr$, and $K_3=0.011d$ and $K_4=0.017d$, respectively. The most reasonable explanation for both cycles is a pair of light-travel-time effects driven by the possible existence of an unseen third and fourth components with projected masses of $M_3=0.91M_{\odot}$ and $M_4=1.09M_{\odot}$ in eccentric orbits of $e_3=0.13$ and $e_4=0.73$. Because no third light was detected in the light curve synthesis, each circumbinary object could be a compact star or a binary itself.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.1
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• pp.49-59
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• 2021

This study investigated the use of real-time PCR melting curves for the diagnosis of blaKPC and blaNDM genes among the most frequently detected carbapenemase-producing Enterobacteriaceae in Korea. As a means of addressing the shortcomings of phenotype tests and conventional PCR. The modified Hodge test confirmed positivity in 25 of 35 strains, and carbapenemase inhibition testing confirmed positivity in 14 strains by meropenem+PBA or meropenem+EDTA. PCR analysis showed amplification products in 25 strains of Klebsiella pneumoniae carbapenemases (KPC), 10 of K. pneumoniae, 5 of E. coli, 5 of A. baumannii, 4 of P. aeruginosa, and 1 of P. putida. New Delhi metallo β-lactamase (NDM) identified amplification products in 8 strains, that is, 2 K. pneumoniae, 3 E. coli, 1 P. aeruginosa, 1 E. cloacae, and 1 P. retgeri strains. Real-time PCR melting curve analysis confirmed amplification in 25 strains of KPC and 8 strains of NDM, and these results were 100% consistent with PCR results. In conclusion, our findings suggest early diagnosis of carbapenem resistant Enterobacteriaceae by real-time PCR offers a potential means of antibacterial management that can prevent and control nosocomial infection spread.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.196-201
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• 2011

BACKGROUND: Bioavailability enhancement by solubilization of lipophilic drugs in nano-emulsion has been reported and it may be useful in pharmaceutical and nutraceutical products. This study was performed to compare in vivo bioavailability of nano-emulsion formulation with that of the general product as control. METHODS AND RESULTS: The pharmacokinetics assessment of Vitamin A, D and E complex of nanoemulsion formulation (LaVita), in comparison to the general product, was performed in the male rat plasma by a single oral dose at 20 mL/kg body weight (n=3/group). For nano-emulsion formulation (LaVita), $C_{max}$ of vitamin A and E in plasma were much higher and the area under the curve (AUC) of vitamin A, D and E were 14-63% higher, and the half-life of vitamin E was 2-fold longer than the general product. According to statistical analysis, each $C_{max}$ of vitamin A, D & E was significantly higher (p<0.01, 0.05 and 0.01, respectively) than that of general product. Half-life of vitamin A was significantly higher (p<0.01) and AUC of vitamin A and D were also significantly higher than the general product. CONCLUSION(s): Considering significant increment of $C_{max}$ and AUC, LaVita made of nano-emulsion could be more effective the absorption rate and extent for bioavailability of vitamin A, D & E than those of general product.

• Nutrition Research and Practice
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• v.1 no.3
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• pp.184-188
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• 2007

The major goal in the treatment of diabetes mellitus is to achieve near-normal glycemic control. To optimize both fasting blood glucose and postprandial glucose levels is important in keeping blood glucose levels as close to normal as possible. ${\alpha}-Glucosidase$ is the enzyme that digests dietary carbohydrate, and inhibition of this enzyme could suppress postprandial hyperglycemia. The purpose of this study was to test the inhibitory activity of methanol extract of Euonymus alatus on ${\alpha}-glucosidase$ in vitro and in vivo to evaluate its possible use as an anti-diabetic agent. Yeast ${\alpha}-glucosidase$ inhibitory activities of methanol extract of E. alatus were measured at concentrations of 0.50, 0.25, 0.10, and 0.05 mg/ml. The ability of E. alatus to lower postprandial glucose was studied in streptozotocin-induced diabetic rats. A starch solution (1 g/kg) with and without E. alatus extract (500 mg/kg) was administered to diabetic rats by gastric intubation after an overnight fast. Plasma glucose levels were measured at 30, 60, 90, 120, 180, and 240 min. Plasma glucose levels were expressed in increments from baseline, and incremental areas under the response curve were calculated. Extract of E. alatus, which had an $IC_{50}$ value of 0.272 mg/ml, inhibited yeast ${\alpha}-glucosidase$ activity in a concentration-dependent manner. A single oral dose of E. alatus extract significantly inhibited increases in blood glucose levels at 60 and 90 min (p<0.05) and significantly decreased incremental response areas under the glycemic response curve (p<0.05). These results suggest that E. alatus has an antihyperglycemic effect by inhibiting ${\alpha}-glucosidase$ activity in this animal model of diabetes mellitus.

• Journal of Gastric Cancer
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• v.18 no.1
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• pp.90-98
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• 2018

Purpose: We evaluated the learning curve and short-term surgical outcomes of robot-assisted distal gastrectomy (RADG) performed by a single surgeon experienced in open, but not laparoscopic, gastrectomy. We aimed to verify the feasibility of performing RADG without extensive laparoscopic experience. Materials and Methods: Between July 2012 and December 2016, 60 RADG procedures were performed by a single surgeon using the da $Vinci^{(R)}$ Surgical System (Intuitive Surgical). Patient characteristics, the length of the learning curve, surgical parameters, and short-term postoperative outcomes were analyzed and compared before and after the learning curve had been overcome. Results: The duration of surgery rapidly decreased from the first to the fourth case; after 25 procedures, the duration of surgery was stabilized, suggesting that the learning curve had been overcome. Cases were divided into 2 groups: 25 cases before the learning curve had been overcome (early cases) and 35 later cases. The mean duration of surgery was 420.8 minutes for the initial cases and 281.7 minutes for the later cases (P<0.001). The console time was significantly shorter during the later cases (168.6 minutes) than during the early cases (247.1 minutes) (P<0.001). Although the volume of blood loss during surgery declined over time, there was no significant difference between the early and later cases. No other postoperative outcomes differed between the 2 groups. Pathology reports revealed the presence of mucosal invasion in 58 patients and submucosal invasion in 2 patients. Conclusions: RADG can be performed safely with acceptable surgical outcomes by experts in open gastrectomy.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.1
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• pp.63-70
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• 1994

Single crystals of the superionic conductor ${\beta}-Ag_3SI$ were prepared by thermal treatmentr from the reactant mixture of AgI and $Ag_2S$. The growing single crystals were made to spherical shape of $200{mu}m$ in diameter. The detailed structures analyses revealed that $Ag^+$ in ${\beta}-Ag_3SI$ distribute on 12h site of 4-coordination inpreference to 3c site of 6-coordination. The effective one-particle potential (o.p.p.). of $Ag^+$ along [110] direction was evaluated from the probability density function(p.d.f.) Activation energy calculated from the o.p.p. curve has been found to be 0.012 eV for the diffusion of $Ag^+$ on (001) plane in the ${\beta}-Ag_3SI$ structure.