• Journal of the Korean earth science society
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• v.22 no.4
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• pp.278-291
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• 2001

Mesothermal gold vein minerals of the Seolhwa mine were deposited in a single stage of massive quartz veins which filled the mainly NE-trending fault shear zones exclusively in the granitoid of the Gyeonggi Massif. The Seolhwa mesothermal gold mineralization is spatially associated with the Jurassic granitoid of 161 Ma. The vein quartz contains three main types of fluid inclusions at 25$^{\circ}$C: 1) low-salinity (< 5 wt.% NaCl), liquid CO$_{2}$-bearing, type IV inclusion; 2) gas-rich (> 70 vol.%), aqueous type II inclusions; 3) aqueous type I inclusions (0${\sim}$15 wt.% NaCl) containing small amounts of CO$_{2}$. The H$_{2}$O-CO$_{2}-CH$_{4}$-N$_{2}$-NaCl inclusions represent immiscible fluids trapped earlier along the solvurs curve at temperatures from 430$^{\circ}$ to 250$^{\circ}$C and pressures of 1 kbars. Detailed fluid inclusion chronologies may suggest a progressive decrease in pressure during the auriferous mineralization. The aqueous inclusion fluids represent either later fluids evelved through extensive fluid unmixing (CO$_{2}-CH$_{4}$ effervescence) from a homogeneous H$_{2}$O-CO$_{2}-CH$_{4}$-N$_{2}$-NaCl fluid due to decreases in temperature and pressure, or the influence of deep circulated meteoric waters possibly related to uplift and unloading of the mineralizing suites. The initial fluids were homogeneous containing H$_{2}$O-CO$_{2}-CH$_{4}$-N$_{2}$-NaCl components and the following properties: the initital temperature of >250$^{\circ}$ to 430$^{\circ}$C, X$_{CO}\;_{2}$ of 0.16 to 0.62, 5 to 14 mole% CH$_{4}$, 0.06 to 0.3 mole% N$_{2}$ and salinities of 0.4 to 4.9 wt.% NaCl. The T-X data for the Seolhwa gold mine may suggest that the Seolhwa auriferous hydrothermal system has been probably originated from adjacent granitic melt which facilitated the CH$_{4}$ formation and resulted in a reduced fluid state evidenced by the predominance of pyrrhotite. The dominance of negative ${\delta}\;^{34}$S values of sulfides (-0.6 to 1.4$%_o$o) are consistent with their deep igneous source.

• The Korean Journal of Pesticide Science
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• v.8 no.1
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• pp.38-45
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• 2004

To elucidate the photolysis characteristics of the insecticide imidacloprid in the environment, $[^{14}C]$imidacloprid was treated into water and paddy soil-water system. In water system, the amount of $^{14}C$-radioactivity distributed in aqueous phase was rapidly increased up to 80% of total $^{14}C$ in water during 7 days of exposure to sunlight. Also, the amounts of imidacloprid in water at day 0 and 3 days after treatment were 1.2461 and 0.8594 mg/kg, respectively, not being detected 7 days after treatment, indicating rapid degradation of imidacloprid in water by sunlight. One photodegradation product, imidacloprid urea, in which the $N-NO_2$ moiety of imidacloprid was replaced by oxygen, was detected from water in water and water-paddy systems. The amount of the metabolite detected from water in water system was 0.0112 mg/kg 1 day after treatment and reached the top concentration of 0.0391 mg/kg 7 days after treatment. In case of water-paddy system, its amount was 0.0117 mg/kg 1 day after treatment and reached the highest concentration of 0.0259 mg/kg 3 days after treatment. Rapid transformation of imidacloprid into polar compounds continued until 7 days after treatment, considering that 80% of $^{14}C$ in water distributed in aqueous phase 7 days after treatment, amount of imidacloprid was 1.6538 mg/kg at day 0 and 0.8785 mg/kg 1 day after treatment, not being detected after 15 days, indicating rapid degradation of imidacloprid in water-paddy soil system by sunlight. The direct degradation of imidacloprid to imidacloprid urea would be a major photodegradation pathway in water and water-paddy soil systems.

• Korean Journal of Microbiology
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• v.23 no.2
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• pp.129-137
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• 1985

The RK-temperate phage which infected with Bacillus cereus was isolated and the characters were investigated. The induction of RK-temperate phage from host bacterium attained by ultraviolet light irradiation (15W, 30cm, 30-120sec) and mitomycin C treatment (0.2-2 ug/ml). The host range of RK-temperate phage was not revealed with lysogenic and related strains of B. cereus. But B. cereus(PS) 352 which obtained by N-nitrosoguanidine treatment (1,000{$\mu}g/ml)$ to phage infected with host bacteria was sensitive bacteria of RK-temperate phage. RK-temperate phage was stabilized at the condition of nutrient broth (pH 7-8), Tris-buffer (pH 7-8) and ammonium buffer (pH 8-9) and Sorensen's phosphate buffer (pH 6-7), but unstabilized at other salt solutions and pH range. Also, thermostability was to $45^{\circ}C$ but unstabilized at above $50^{\circ}C$. At RK-temperate phage, the measurment values of head, neck, mid tail and end tail were 59nm, $9{\times}16nm,\;10{\times}189nm,\;and\;10{\times}14nm$ respectively. The morphology of head was regular polyhedron, and the end tail was coneate form. On the one hand, the number of capsid protein layer of tail were consist of 4, 35, and 1 at neck, mid tail, and end tail, respectively. RK-temperate phage was identified with DNA phage and G+C contents were 38.63. The latent time of RK-temperate phage was 30 minutes and the burst size was 70-80. And the host bacteria was lysed in case of multi-infection, above moi 1.

• Korean Journal of Microbiology
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• v.16 no.2
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• pp.79-89
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• 1978

The RK-temperate phage which infected with Bacillus cereus was isolated and the characters were investigated. The induction of RK-temperate phage from host bacterium attained by ultraviolet light irradiation (15W, 30cm, 30-120sec) and mitomycin C treatment (0.2-2 ug/ml). The host range of RK-temperate phage was not revealed with lysogenic and related strains of B. cereus. But B. cereus(PS) 352 which obtained by N-nitrosoguanidine treatment(1,000.$\mu$g/ml) to phage infected with host bacteria was sensitive bacteria of RK-temperate phage. RK-temperate phage was stabilized at the condition of nutrient broth (pH 7-8), Tris-buffer (pH 7-8) and ammonium buffer (pH 8-9) and Sorensen's phosphate buffer (pH 6-7), but unstabilized at other salt solutions and pH range. Also, thermostability was to 45.deg.C but unstabilized at above 50.deg.C. At RK-temperate phage, the measurment values of head, neck, mid tail and end tail were 59nm, 9*16nm, 10*189nm, and 10*14nm respectively. The morphology of head was regular polyhedron, and the end tail was coneate form. On the one hand, the number of capsid protein layer of tail were consist of 4, 35, and 1 at neck, mid tail, and end tail, respectively. RK-temperate phage was identified with DNA phage and G+C contents were 38.63. The latent time of RK-temperate phage was 30 minutes and the burst size was 70-80. And the host bacteria was lysed in case of multi-infection, above moi 1.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.10
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• pp.1333-1339
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• 2010

The present study was conducted to determine plasma acetate, glucose and protein metabolism using dilution of isotopes [[1-$^{13}C$]Na acetate, [U-$^{13}C$]glucose and [1-$^{13}C$]leucine (Leu)] in sheep fed rice straw (Oriza japonica L.). Four sheep were assigned to either rice straw (RS-diet) or mixed hay (MH-diet) with a crossover design. Nitrogen (N) intake and N digestibility were lower (p = 0.002 and p = 0.02, respectively) for RS-diet than MH-diet, but N retention did not differ (p>0.10) between the diets. Concentrations of rumen acetate tended to be lower (p = 0.07), and propionate was higher (p = 0.02) for RS-diet than MH-diet. Concentrations of plasma lactate, non-esterified fatty acids, Leu and ${\alpha}$-ketoisocaproic acid did not differ (p>0.10) between the diets, but plasma glucose and urea concentrations were lower (p = 0.01 and p = 0.003, respectively) for RS-diet than MH-diet. Turnover rate of plasma acetate did not differ (p = 0.39) between the diets, and plasma glucose and Leu turnover rates were numerically lower (p = 0.15 and p = 0.14, respectively) for RS-diet than MH-diet. Whole body protein synthesis and degradation did not differ (p>0.10) between the diets. Thus it can be concluded that the intermediary metabolism of acetate, glucose and protein on rice straw is comparable to mixed hay in sheep.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.645-650
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• 2005

To reduce ammonia-like odor in chondroitin sulfate, longnose skate (Rasa rhina) cartilage was processed by washing, autoclaving, and alkali pretreatments. Content of total volatile basic nitrogen (TVB-N), index of ammonia-like odor, of raw skate cartilage without pretreatment was 254 mg/100 g, whereas those of skate cartilage pretreated with washing and autoclaving increased to 630 and 636 mg/100 g, respectively. TVB-N of skate cartilage pretreated with sodium hydroxide sharply decreased to 15 mg/l00 g at optimal condition of 0.12 M and 3.6 volume of NaOH, as determined by surface response methodology of central composite design for optimization. Alkali pretreatment resulted in 97.6% deodorizing. Washing and autoclaving pretreatments had almost no effect on the yield of chondroitin sulfate (approximately 30%), whereas decreased to 16.0% after alkali pretreatment, showing chondroitin sulfate of skate cartilage as chondroitin sulfate C.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.3
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• pp.291-300
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• 1999

In order to investigate the oceanic condition of fishing ground in the southwestern coastal sea of Korea, the oceanographic observation were carried out by the trainingship of Yosu university on May, August and November in 1998. Main features in the observation are as follows; 1) the ranges of temperature, salinity, density and chlorophyll-a were from $14.5^{\circ}C\;to\;18.0^{\circ}C,\; from\;33.5\textperthousand\;to\;34.5\textperthousand$from 24.0 to 25.5 and from $1.0\mu$g/l in spring (May) from $15.0^{\circ}C\;to\;27.5^{\circ}C,\;from\;0.0\textperthousand\;35.0\textperthousand$9.0 to 26.0 and from 0.5$\mu\textrm{g}$/l to 4.0$\mu\textrm{g}$/l in summer(August), and from $ to 21.0^{\circ}\;31.0\textperthousand$, from 22.0 and from $4.0\mug/l\;to\;20.0\mug/l$ in autumn(November), respectively, 2) the temperature in the coastal region was higher than that in the open ocean while salinity, density and chlorophyll-a were lower, and the convection was identified between the surface and the bottom during in spring and autumn, 3) the chlorophyll-a in the this region was varied in each season, being highly distributed offshore Yosu Bay, 4) on evidence of sea water intrusion toward Kumun island was observed.

• Molecules and Cells
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• v.20 no.2
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• pp.210-218
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• 2005

The rice genome contains at least 28 EXPA (${\alpha}$-expansin) genes. We have obtained near full-length cDNAs from the previously uncharacterized genes. Analysis of these newly identified clones together with the 12 identified earlier showed that the EXPA genes contain up to two introns and encode proteins of 240 to 291 amino acid residues. The EXPA proteins contain three conserved motifs: eight cysteine residues at the N-terminus, four tryptophan residues at the C-terminus, and a histidine-phenylalanine-aspartate motif in the central region. EXPA proteins could be divided into six groups based on their sequence similarity. Most were strongly induced in two-day-old seedlings and in the roots of one-week-old plants. However, only 14 genes were expressed in the aboveground organs, and their patterns were quite diverse. Transcript levels of EXPA7, 14, 15, 18, 21, and 29 were greater in stems, while EXPA2, 4, 5, 6, and 16 were highly expressed in both stem and sheath but not in leaf blade. EXPA1 is leaf blade-preferential, and EXP9 is leaf sheath-preferential. Most of the root-expressed genes were more strongly expressed in the dividing zone. However, the Group 2 EXPA genes were also strongly expressed in both mature and dividing zones, while EXPA9 was preferentially expressed in the elongation zone. Fourteen EXPA genes were expressed in developing panicles, with some being expressed during most developmental stages, others only as the panicles matured. These diverse expression patterns of EXPA genes suggest that in general they have distinct roles in plant growth and development.

• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.4
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• pp.293-299
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• 2004

An active RC 2nd order Butterworth filter suitable for a baseband channel-selection filter of a direct conversion receiver is presented. The linearity of the 2nd order Butterworth filter is analyzed. In order to improve the linearity of the filter, the operational amplifiers should have a high linear gain and low 3rd harmonic, and the filter should be designed to have large feedback factor. This second order Butterworth filter achieves-14dBV in-channel (400kHz, 500kHz) IIP3, +29dBV out-channel (10MHz, 20.2MHz) IIP3 and 15.6 $nV/\sqrt{Hz}$ input-referred noise and dissipates 10.8mW from a 2.7-V supply. The analysis and experimental results are in good agreement

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.347-355
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• 1986

The Sonakdong river is very important water source not only for agricultural water of Kimhae field but also for fishery water. Recently the middle and lower areas of the river have the tendency to be heavily contaminated by domestic sewage and agricultural chemicals. Fifty six water samples were collected from 8 stations from July to December in 1985 for the experiment (Fig. 1). To evaluate the water quality, pH, water temperature, electrical conductivity, chloride ion, nutrients ($NO^{-}_{2}-N,\;NO^{-}_{3}-N,\;NH^{+}_{4}-N,\;PO^{3-}_{4}-P,\;SiO_2-Si$), total coliform, fecal coliform, and fecal streptococcus were determined. Range and mean value of the samples were as follows; pH $6.3{\sim}9.4$, 7.91; water temperature $6.1{\sim}34.8^{\circ}C,\;23.88^{\circ}C$; electrical conductivity (from St. A to G) $1.575{\times}10^2{\sim}30.50{\times}10^2{\mu}{\mho}/cm,\;6.57{\times}10^2{\mu}{\mho}/cm$; chloride ion $23.5{\sim}14,300mg/l$, 770.0mg/l; nitrite-nitrogen $0.007{\sim}0.110mg/l$, 0.053mg/l; nitrate-nitrogen $0.001{\sim}1.638mg/l$, 0.649 mg/l; ammonia-nitrogen $0.017{\sim}4.200mg/l$, 0.497mg/l; phosphate-phoshorus $0.011{\sim}0.281mg/l$, 0.086mg/l; and silicate-silicious $2.4{\sim}6.5mg/l$, 4.43mg/l. Electrical conductivity and chloride ion of the station F(Chomanpo) were $2.676{\times}10^2{\mu}{\Omega}cm$ and 123.99mg/l which were lower than those of others. Among the analyzed nutrients, silicate-silicious concentration was the highest through all the samples. The bacterial density of the samples ranged $36{\sim}110,000/100ml$ for total coliform, $15{\sim}46,000/100ml$ for fecal coliform and $3.6{\sim}15,000/100ml$ for fecal streptococcus. The range and the mean of the TC/FC ratio were $3.0{\sim}9.6$, 5.51 and those of the FC/FS ratio were $1.1{\sim}9.2$, 6.19, respectively. On the other hand, fecal coliform was not detected in about $78\%$ of the water samples examined. Composition of coliform was $52\%$ Escherichia coli group, $3\%$ Citrobacter freundii group, $13\%$ Enterobacter aerogenes group and $31\%$ others.