• Journal of Korean Society for Atmospheric Environment
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• v.2 no.3
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• pp.57-63
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• 1986

Atmospheric particulate matter (A.P.M.) was collected on quartz fiber filters from March 1985 to May 1986 according to particle size using Andersen high-volume air sampler, and 6 heavy metals (Fe, Mn, Cu, Ni, Zn, Pb) in these particulates were analyzed by atomic absorption spectrophotometry. The arithmetic mean concentration of A.P.M. was 195.57$\mug/m^3$. The arithmetic mean concentrations of 6 metals (Fe, Mn, Cu, Ni, Zn and Pb) were 3385.04, 1451.67, 897.94, 159.68, 127.14 and 59.49 $ng/m^3$ respectively. The order of heavy metals contributing to A.P.M. was as follows: Fe > Zn > Pb > Cu > Mn > Ni. These heavy metals were devided into 3 groups according to their particle size distribution. The contents of heavy metals belonging to the 1st group (Fe, Mn) were increased with the particle size. On the contrary, the content of Pb belonging to the 2nd group (Pb) was increased with the decrease in the particle size. The heavy metal contents in the 3rd group (Ni, Cu, Zn) were lowest in the particle size range of 2.0-3.3 $\mum$ compared with particles larger or smaller tha this range. The seasonal variation of heavy metal concentration were as follows: Fe and Mn contents were highest in spring, but Ni and Pb contents were highest in winter. Statistical analysis showed that there was a significant correlation between A.P.M. and Fe in coarse particles, meanwhile between A.P.M. and Pb in the case of fine particles.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.45-50
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• 2003

This study was conducted to understand the role of oxidative enzyme cytochrome $P_{450}$ in the bioactivation of benfuracarb and to know metabolites of benfuracarb by cytochrome $P_{450}$. The bimolecular imhibition rate constant $(k_i)$ of benfuracarb on acetylcholinesterase (AChE) was as low as $1.1{\times}10^3\;M^{-1}\;min^{-1}$, suggesting that benfuracarb should be activated for its toxic action. The potency of benfuracarb on AChE in the oxidase system (cytochrome $P_{450}$ + NADPH) in vitro was 10-fold higher than that of control (cytochrome $P_{450}$). Such a similar result was also found in the oxidase + PBO system. In vivo the $I_{50}$ of benfuracarb was 22.7mg $kg^{-1}$, but pie-treatment of piperonyl butoxide (PBO) reduced the $I_{50}$ by >100mg $kg^{-1}$. This result suggests that cytochrome $P_{450}$ was involved in the activation of benfuracarb. Using microsomal oxidase system, metabolites of benfuracarb were elucidated. Fifty-eight percent of benfuracarb was converted to carbofuran, a major toxic metabolite, in the oxidase system, while only less than two percent of benfuracarb was converted to carbofuran in the oxidase + PBO system. These results also suggest that cytochrome $P_{450}$ was involved in the activation of benfuracarb. Overall results indicate that cytochrome $P_{450}$ could be involved in the bioactivation of benfuracarb to carbofuran.

• Korean Journal of Veterinary Service
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• v.29 no.1
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• pp.9-18
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• 2006

The ELISA titers to avian pneumovirus (APV) and avian reovirus (ARV) were surveyed to sera of 38 breeder farms (78 blocks, 1,560 hens) in Jeonbuk province during February to October, 2005. In APV, the positive ELISA were detected 36 (94.7%) breeders, 71 (91.0%) blocks, 1,057 (67.8%) hens, and their S/P ratio was 1.940. Regionally, the positivity of 24 breeders farms in the Jeonju, Jeongeup, Namwon, and Jangsu were noted as 100%, whereas 85.7% in Iksan. The positivity to species such as Cobb (20), Ross (13) and Hanhyup-3 (5), all of the breeding farms were detected as positive, 40 (86.9%), 17 (94.4%) and 14 (100.0%) in blocks, 553 (60.1%), 285 (79.2%) and 219 (78.2%) in hens, and their mean S/P ratio were 1.677, 1.769 and 2.254, respectively. The positivity of the breeders vaccinated with ARV, all of the 9 breeder farms (38 blocks) were noted as 100%, but 627 (82.5%) in hens, and its mean S/P ratio was 1.273. Whereas nonvaccinated with ARV were 28 (96.5%) in breeders farms, 38 (95.0%) in blocks, 660 (82.5%) in hens, and the mean S/P ratio was 1.612. In species which were vaccinated with ARV, 11 breeder farms (38 blocks) were noted as 100%, but 82.5% in hens, and their mean S/P ratio were 1.315. Whereas in nonvaccinated with ARV, 25 (92.6%) in farms, 38 (95.0%) in blocks and 660 (82.5%) in hens were positive, and their mean S/P ratio was 1.532.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.12-17
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• 2003

Potato blackleg disease caused by Erwinia carotovora subsp. atroseptica (Eca) has been a serious problem in Korea. Bactericidal activities of twelve bactericides including antibiotics, copper compounds and oxolinic acid were examined in vitro. Streptomycin, streptomycin sulfate, and oxolinic acid effectively controlled the pathogen at 0.02 mM. However, the pathogen developed resistance to the applied bactericides after 72 hours of incubation. Activity of copper compounds such as copper hydroxide, copper oxide and copper sulfate was lower than that of antibiotics. However, the pathogen did not develop resistant to them. Combinations of streptomycin (0.016 mM, 9.3 ppm) + copper oxide (1.2 mM, 171.6 ppm)/copper hydroxide (1.5 mM, 146.3 ppm); streptomycin sulfate (0.005 mM, 7.0 ppm) + copper oxide (1.2 mM, 171.6ppm)/copper hydroxide (1.5 mM, 146.3 ppm) were found to be effective for the control of E. carotovora subsp. atroseptica.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.1
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• pp.1-6
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• 1974

Meretrix lusoria is one of the most favorite edible bivalves inhabiting wide inter-tidal flats along the western coast of Korea. Over the period of July to September 1973, some specimens from a tidal flat near AnMyun Island were submerged in sea water with various concentrations of ammo-mum hydroxide added and careful observations were made on their fertilization, early development, and metamorphosis of the larvae. The highest rate of fertilization was demonstrated by individuals treated with 1/1000 normal solution of ammonium hydroxide, and their fertilized eggs followed normal development, i. e., two cell stage in 1.2 hours after fertilization, gastrula stage after 4.7 hours, and trochophore stage after 5.6 hours. Within 24 hours after fertilization M. lusoria larvae have acquired the form of early straight-hinge veliger with the mean prodissoconch I length of $112\mu$. It takes seven days to get the umbo stage with the mean shell length of $172\mu$ and twenty days to get the metamorphosing stage with the mean shell length of $232\mu$. The larvae were cultured to the metamorphosing stage with the shell length of $272\mu$ in the laboratory condition. The relationship between the shell length (L) and the shell height (H) in veliger stage is shown as H=1.02325L-24.46425 with a significant difference.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.370-375
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• 2015

This experiment compared the regeneration conditions of the radiation mutant spray chrysanthemum 'purple ND'. The four different flower blooming stages (S1: 10% opened flower, S2: 30% opened flower, S3: 50% opened flower, and S4: 70% opened flower) and different petal parts (TBOP: the basal of petal and TEOP: the end of petal) were used to compare regeneration conditions between plants grown in MS medium supplemented with IAA and BAP. The highest adventitious shooting rate was identified in plants grown on the IAA $1.0mg{\cdot}L^{-1}$ and BAP $2.0mg{\cdot}L^{-1}$ when using the end of petal at the S2 stage. It displayed 79.2% regeneration and produced 33.4 shoots. Rooted plantlets were successfully established in the greenhouse, showing the same morphological characteristics of vegetative and reproductive organs with those of the mother plant. Flow cytometry analysis revealed no ploidy variation between the regenerated plants and the mother plant grown under greenhouse conditions.

• Parasites, Hosts and Diseases
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• v.36 no.3
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• pp.171-182
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• 1998

A total of nine Korean native kids and two Corriedale lambs, 1-20 days old, were each inoculated per os with a single dose of 2 × 107 oocysts of Cwptospori,mum muris (strain MCR) originated from mice to elucidate the kinetics and developmental stages of the coccidium in small ruminants. Irrespective of host's age, the prepatent period for both animals ranged from 19 to 35 days (28.1 days, on the average) and the patent period 16-85 days (47.8 days), and the total oocyst outputs showed enormous differences. Infection with greater numbers of oocyst outputs was not ordinarily established by transmission experiments. Oocysts discharged from the kids retained their infectivity by the mouse titration method. The immunogenicity of the coccidium and oocyst reproduction were proven by challenge infection and administration of prednisolone acetate. respectively. All the developmental stages of the coccidium in parasitophorous vacuoles were found by transmission electron microscopy in the pits of the gastric glands of a kid inoculated with oocysts and then necropsied on day 44 postinoculation. It indicated the full course of the host-parasite relationship in kids and lambs as well as mice.

• KSBB Journal
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• v.14 no.1
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• pp.82-90
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• 1999

In order to eventually fabricate an analytical system for infectious microorganisms, we synthesized major immunochemical components, utilized them for the construction of model system, and investigated an assay concept for bacterial whole cells. For the preparation of system components, a polyclonal antibody, against Salmonella thompson as model analyte, purified by immuno-affinity chromatography was used to chemically link to streptavidin or an enzyme, horseradish peroxidase(HRP). The antibody and streptavidin was modified with sulfosuccinimidyl 4-[N-maleimidomethyl]cyclohexane-1-carboxylate and N-succinimidyl-3-[2-pyridyldithio]propionate(subsequently activated by dithiotheritol), respectively. The modified components were reacted to synthesize antibody-streptavidin conjugates which were then purified on a two-layer chromatography column of diaminobiotin gel and Sephadex G-100. For antibody-HRP conjugates, HRP molecules were activated by $NalO_4$ oxidation and then coupled to immunoglobulin. After stabilizing with ($NaCNBH_3$, the conjugates were purified by size exclusion chromatography on Biogel A5M column. To devise a model system, such produced components were combined with a dot-blotter in which a nitrocellulose membrane($12{\mu}m$ pre size) with immobilized biotin was already located. The analyte (S. thompson cells) was reacted with the both antibody conjugates in a liquid phase, and the complexes formed were captured on the membrane surfaces by applying vacuum in the bottom compartment of the blotter to invoke biotin-streptavidin reaction. Under optimal conditions, the system enabled to identify the analytical concept for bacterial whole cells, and the lower limit of detection was approximately $1{\mu}g/m{\ell}$($10^5-10^6$ cells/m$m{\ell}$). The controlling factors were the concentrations of each antibody conjugate that caused agglutination in the presence of analyte as they increased.

• Food Science and Preservation
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• v.13 no.2
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• pp.180-185
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• 2006

Prunus mume has been used as a Korean medicine. It is effective in treating diarrhea and an abdominal pain. This experiment was carried out to optimize extraction conditions of prunus mume flower tea and to analyze volatile compounds. Three kinds of samples treated with fresh, freeze dry, and shade dry, were used, and prunus mum flower tea was manufactured by the mixed ratio of green tea and prunus mume flower. The result was valued by the Hunter's value, flavor and taste. The optimum conditions of extraction time and temperature were 3 min and $80^{\circ}C$ respectively. Sensory evaluation shows that optimum ratio was adaptive 90% green tea with 10% prunus mume flower. The major volatile compound in prunus mume flower was benzaldehyde.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.167-174
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• 1995

This experiment was carried out to investigate the major characters affecting the popping volume of popcorn. Tuygimok 1 (Kp1 ${\times}$ Kp2) and 8 popcorn hybrids' agronomic characters were tested to evaluate a certain extent how much they affect on the popping volume. Moisture con-tent was considered as the most important factor, but failed to evaluate the optimum moisture con-tent level in this experiment moisture range (12.2-14.4%) because popping volume increased as moisture content of kernels increased. The maximum popping volume was obtained at 55-60kg of kernel hardness, 80-90,um of pericarp thickness and 45-50% of S/H (Soft/Hard starch). But the Em/En(Embryo/Endosperm) ratio was negatively associated with the popping volume. Therefore the minimum popping volume was observed at the 10-11 % of Em/En ratio. Moisture content, hardness, pericarp thickness, Em/En and S/H ratio were selected as the appropriate variables for the maxi-mum popping volume using the stepwise forward regression method and the expecting popping volume was estimated by the multiple linear regression formular. The mean popping volume of ninepopcorn hybrids was about 29.2cm3/g.