• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.155-163
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• 1998

The purpose of this study was to determine the association between blood lipids, fibrinogen, fasting blood sugar, lifestyle-related factors and lipoprotein(a). This study was performed with 140 healthy adults (male:80, female:60) among the teachers in primary, middle, and high school in Seoul in November 1996. Lipoprotein(a) concentration was measured with an enzyme-linked-immunosorbents assay(ELISA), and the results showed that the distribution was highly skewed and the average concentrations of male and female were $16.94{\pm}12.70\;mg/dL\;and\;17.92{\pm}7.58\;mg/dL$, respectively. The percentage of subject with lipoprotein(a) concentrations higher than 30 mg/dL was 26.4%. Univariate analysis showed significant association between lipoprotein(a) and age, alcohol, meat, and NaCl consumption (p<0.05). In multivariate analysis, lipoprotein(a) correlated positively with age (p<0.05) and meat consumption (p<0.01). These data suggest that lifestyle-related factors may affect the lipoprotein(a) concentration regarded as a risk factor of atherosclerosis disease.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.421-426
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• 1999

This study was conducted to examine the quality of low-salt Mul-kimchi which was prepared by mixing of radish (25%), green onion (2.4%), red pepper (1.9%), garlic (1.9%) and salt (0, 0.2, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0%) in water and followed by fermentation at 4, 15 and $25^{\circ}C$ for 10 days, respectively. The pH was lowest and acidity was highest in the Mul-kimchi containing 1.0% salt. The total vitamin C contents in Mul-kimchi containing $0{\sim}0.2%$ salt were high at the early stage of fermentation while those of Mul-kimchi containing 3.0% salt were higher than the low-salt samples after the optimal ripening time. The hardness of the radish increased with the salt concentration. Overall palatability of Mul-kimchi showed the highest score in 1.0% salt sample.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.72-76
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• 2003

Ultrafiltration (UF) tests performed on traditional soy sauce (kanjang) using UF flat membrane test cell unit with thin film laminar flow similar to the spiral type membrane module in batch operations revealed reduction in permeate flux is proportional to the logarithm values of volume reduction ratio of the retentate kanjang at different feed rate of kanjang. Feed rate of 1.5 L/min was found to be adequate for long-term UF operation of kanjang using the test unit attached with MW cut-off size of 200,000 dalton polyoleffin plastic membrane in batch operation with the least concentration polarization. The higher the feed rate of kanjang, the lower the permeability of total nitrogen and NaCl, resulting in lower optical density at 500 nm and lower permeability of minerals such as Cu, Mn, and Mg. Microbial cells were completely rejected regardless of the feed rate, whereas most free amino acids were not.

• Journal of Aquaculture
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• v.16 no.1
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• pp.1-7
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• 2003

A new technique combining forced-feeding and dorsal aorta cannulation was developed to monitor concentration of nutritions in the blood circulation and their metabolites in rainbow trout. To study the effect of dorsal aorta cannulation on stress, 30 rainbow trout (523$\pm$5.4 g; Mean$\pm$SD) were divided into 6 groups of 5 individuals each. A group was anesthetized and blood samples were taken at 0, 3, 6, 12, 24 or 48 h after dorsal aorta cannulation. Hematocrit peaked at 6 h and returned to 0 values by 12 h after dorsal aorta cannulation. Plasma cortisol and glucose concentrations also peaked at 6 h and returned to 0 values by 48 h after dorsal aorta cannulation. Based on the plasma cortisol and glucose concentrations, the rainbow trout recovered from the operation of dorsal aorta cannulation within 48 h. To compare the patterns of plasma free amino acid concentrations after force-feeding in the fish with dorsal aorta cannulation, 5 dorsal aorta cannulated individuals (511$\pm$6.2 g) were kept in a cage. After 48 h starvation, they were anesthetized and blood samples were taken at 0, 4, 8, 12, 24, 36 or 48 h after forced-feeding. The concentration of all plasma free amino acids, except isoleucine, leucine, phenylalanine, and tryptophan, also peaked at 4 h and returned to 0 values by 24 h after feeding. The combined technique allows forced-feeding and repeated sampling of blood in rainbow trout with minimum stress.

• Polymer(Korea)
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• v.39 no.2
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• pp.338-345
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• 2015

Poly(phenylene oxide) (PPO) and polyether imide (PEI) were sulfonated and aminated to create sulfonated poly(phenylene oxide) (SPPO) and aminated polyether imide (APEI), respectively. Characterization of the SPPO and APEI were performed via measurements of FTIR, thermogravimetry (TGA), swelling degree, ion exchange capacity (IEC), and ion conductivity. Next, the surfaces of these membranes were modified by surface fluorination at room temperature. The surface fluorinated SPPO and APEI membranes underwent characterization again for the mentioned measurements to determine any differences. The 3 types of bi-polar membranes were prepared by varying the IEC of the APEI at a fixed SPPO IEC value, which were applied to the low and high NaCl concentration of feed solution at the different current density, respectively. The hypochlorite concentration derived from the surface fluorinated membranes was dependent on the IEC of the APEI and ranged from 491 to 692 ppm at $80mA/m^2$. At low current density of $5mA/m^2$, the hypochlorite concentrations ranged from 18 to 28 ppm for the 4 hrs surface fluorinated membranes and their durability increased greatly.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.297-302
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• 1990

This study was carried out to investigate the antimicrobial activity of the grapefruit seed extract (GFSE) The antimicrobial activity of GFSE was strong enough against such bacteria as Vibrio vulnificus, Vibrio fluvialis, Bacillus cereus, Staphylococcus aureus and Serratia sp. Growth of the above strains was inhibited by the GFSE'S concentration of 50 ppm. The growth of Vibrio vulnificus was completely inhibited by adding the 50 ppm GFSE to the nutrient broth medium with $3\%$ NaCl. The cell counts of Vibrio uulnfficus $5.2\times10^5$ at first in $5\%$ skim milk containing GFSE 0, 10, 30, 50 and 100 ppm were reduced to 35, 48, $5.6\times10^2,\;5.3\times10^3\;and\;9.6\times10^3/ml$ after 120 hours, respectively. And growth of Aspergillus Parasiticus, Asperillus versicolor, Penicillium funiculosum, Py-renochaeta terrestris and Trichoderma viride were inhibited by the concentration of GFSE 100, 50, 100, 10 and 30 ppm, respectively. The shelf life of Mulkimchi containing GFSE 50 and 100 ppm was 20 days longer than the control during storage at $5^{\circ}C\;and\;20^{\circ}C$.

• Journal of the Korean GEO-environmental Society
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• v.11 no.5
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• pp.61-67
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• 2010

In this study, Solid-phase microextraction (SPME) with GC/FID was studied as a possible alternative to liquid-liquid extraction for the analysis of chlorinated solvents (PCE and TCE) and these by-products (cis-DCE, VC, and Ethylene). Experimental parameters affecting the SPME process (such as kind of fibers, adsorption time, desorption time, volume ratio of sample to headspace, salt addition, and magnetic stirring) were optimized. Experimental parameters such as CAR/PDMS, adsorption time of 20 min, desorption time of 5 min at $250^{\circ}C$, headspace volume of 50mL, sodium chloride (NaCl) concentration of 25% combined with magnetic stirring were selected in optimal experimental conditions for analysis of chlorinated solvents and these by-products. The general affinity of analytes to CAR/PDMS fiber was high in the order PCE>TCE>cis-DCE>VC>Ethylene. The linearity of $R^2$ for chlorinated solvents and these by-products was from 0.912 to 0.999 when analyte concentrations range from $10{\mu}g/L$ to $500{\mu}g/L$, respectively. The relative standard deviation (% RSD) were from 2.1% to 3.6% for concentration of $500{\mu}g/L$ (n=5), respectively. Finally, the limited of detection (LOD) observed in our study for chlorinated solvents and these by-products were from $0.5{\mu}g/L$ to $10{\mu}g/L$, respectively.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.407-416
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• 2019

The criticical micelle concentration (CMC) was measured by using the UV-Vis method for the micellization of the ammonium type cationic surfactants (DTAB, TTAB, and CTAB) in the aqueous aniline solution. The enthalpy change (${\Delta}H^0$) and entropy change (${\Delta}S^0$) were calculated from the dependence of Gibbs free energy change (${\Delta}G^0$) on the temperature for micellization of the cationic surfactants between 290K and 314K. The effects of n-butanol and sodium chloride on the micellization of cationic surfactants were measured and compared with the other thermodynamic functions. All the free energy changes (${\Delta}G^0$) of the micellization were negative, all the enthalpy change (${\Delta}H^0$) were negative, and all the entropy change (${\Delta}S^0$) were positive values, respectively. The micelle formation of cationic surfactant in aniline solution is a spontaneous exothermic reaction, and the iso-structural temperature calculated from the thermodynamic values show that enthalpy and entropy contribution to the micellization are almost the same for the micellization of cationic surfactants

• Journal of Korean Dental Science
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• v.11 no.2
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• pp.71-81
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• 2018

Purpose: The purpose of this study was to investigate the corrosion behaviors of dental implant alloy after microsized surface modification in electrolytes containing Mn ion. Materials and Methods: $Mn-TiO_2$ coatings were prepared on the Ti-6Al-4V alloy for dental implants using a plasma electrolytic oxidation (PEO) method carried out in electrolytes containing different concentrations of Mn, namely, 0%, 5%, and 20%. Potentiodynamic method was employed to examine the corrosion behaviors, and the alternatingcurrent (AC) impedance behaviors were examined in 0.9% NaCl solution at $36.5^{\circ}C{\pm}1.0^{\circ}C$ using a potentiostat and an electrochemical impedance spectroscope. The potentiodynamic test was performed with a scanning rate of $1.667mV\;s^{-1}$ from -1,500 to 2,000 mV. A frequency range of $10^{-1}$ to $10^5Hz$ was used for the electrochemical impedance spectroscopy (EIS) measurements. The amplitude of the AC signal was 10 mV, and 5 points per decade were used. The morphology and structure of the samples were examined using field-emission scanning electron microscopy and thin-film X-ray diffraction. The elemental analysis was performed using energy-dispersive X-ray spectroscopy. Result: The PEO-treated surface exhibited an irregular pore shape, and the pore size and number of the pores increased with an increase in the Mn concentration. For the PEO-treated surface, a higher corrosion current density ($I_{corr}$) and a lower corrosion potential ($E_{corr}$) was obtained as compared to that of the bulk surface. However, the current density in the passive regions ($I_{pass}$) was found to be more stable for the PEO-treated surface than that of the bulk surface. As the Mn concentration increased, the capacitance values of the outer porous layer and the barrier layer decreased, and the polarization resistance of the barrier layers increased. In the case of the Mn/Ca-P coatings, the corroded surface was found to be covered with corrosion products. Conclusion: It is confirmed that corrosion resistance and polarization resistance of PEO-treated alloy increased as Mn content increased, and PEO-treated surface showed lower current density in the passive region.

• The Korea Journal of Herbology
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• v.33 no.5
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• pp.105-110
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• 2018

Objectives : We tried to observe the fluorescence anisotropy and intensity of ethidium ion in the intercalating binding interaction between DNA and ethidium ions in the presence of berberine, and then tried to explain the effect of berberine on the intercalating interaction of ethidium ion with DNA. Methods : DNA(calf thymus DNA), berberine and ethidium bromide(EtBr) were purchased from Sigma-Aldrich Co. Proper amount of each compound was dissolved in 20 mM sodium phosphate buffer(pH 7.0) containing 100 mM of NaCl to prepare stock solutions. Collections of the fluorescence anisotropy and intensity data were performed on JASCO FP-8300 spectrofluorometer equipped with a polarizer and a Peltier temperature controller. The excitation of ethidium ion was done at 550 nm and the emission data were collected at 600 nm. For Stern-Volmer plot, the fluorescence data were collected at $18^{\circ}C$ and $30^{\circ}C$. Results : According to the results of this research, the weak competitive binding pattern between ethidium ion and berberine appeared in binding with DNA at low ratio of DNA to ethidium ion. But at high ratio of DNA to ethidium ion, this weak competition disappeared. Instead, berberine might bind to DNA by intercalating way. In other words, berberine could de-intercalate ethidium ion from DNA at low concentration of DNA relative to ethidium ion, but could not at high concentration of DNA relative to ethidium ion. In addition, the mechanism of fluorescence quenching of ethidium ion could also proceed differently, depending on the ratio of the amount of DNA to that of ethidium ion. Conclusions : The effect of berberine on the DNA-ethidium ion intercalating interaction could work differently, depending on the relative ratio of the amount of DNA to that of ethidium ion. This study also showed that fluorescence anisotropy analysis is very useful method to obtain detailed information for investigation of the complex binding interactions. In order to fully understand the mechanism of action of the pharmacological effect by berberine, studies on the effect of berberine on the action of proteins such as various enzymes closely related to berberine-induced medicinal effects should be continued.