• Korean Journal of Poultry Science
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• v.19 no.1
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• pp.35-45
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• 1992

This study was carried out to investigate the effect of different dose of 312nm UV irradiation on ash and phosphorus contents in metatarsus of broiler chicks, whose dorsal skins were exposed to the UV light. Day old Hubbard line broiler chicks were fed with vitamin D deficient diet for 3 weeks and the defeathered dorsal skins were exposed to different dise (0.32, 0.65, or 0.98 J/$\textrm{cm}^2$) of 312nm UV light. The metatarsus bones were collected on 0, 1, 2, 3, 4 or 5 days after irradiation and defatted, dried, ashed and dissolved in 6N-HCI. The P concentrations were determined by spectrophotometry. When the 0.32 J/$\textrm{cm}^2$ dose was applied, the ash contents in metatarsus bones o( chicks were 42, 46 and 40% on 0, 1 and 3 days after irradiation, respectively. The maximum level, 46% was appeared at 2 days after exposure as 0.65 J/$\textrm{cm}^2$ was treated. When 0.98 J/$\textrm{cm}^2$ irradiation was applied, the high concentrations, 47 and 47% were shown on 1 and 2 days after irradiation, respectively. The 0.98 J/$\textrm{cm}^2$ among three levels of dose increased the most amount of ash in metatarsus bone. In respect to the P content in the chick bone the increased level, 19.4% was shown on 3 days after UV treatment with 0.32 J/$\textrm{cm}^2$. The maximum levels, 18.1 and 20.0% were present on 3 and 2 days after exposure to the 0.65 and 0.98 J/$\textrm{cm}^2$ of UV dose, respectively. It was shown that the higher dose of UV irradiation increased the more P concentration in matatarsus of chicks and the production rate was faster than those from 0.32 and 0.65 J/$\textrm{cm}^2$ treatments.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.2
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• pp.109-124
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• 2014

In order to understand the carbon cycle in the Amundsen Sea of the Southern Ocean, the export fluxes of particulate organic carbon from the euphotic zone to deep water estimated using ${\psi}$/${\psi}$ disequilibrium method. Seawaters in 14 water columns were collected during February and March 2012, and analyzed for total and dissolved ${\psi}$, and particulate organic carbon. Total ${\psi}$ activities in the water column showed deficiency and excess relative to those of ${\psi}$ depending on the water depth. Deficiency of total ${\psi}$ in the euphotic zone showed mirror images both with chlorophyll-a and fluorescence, and was consistent with the loss of nitrate, which indicated the effect of biological activity. In addition, deficiency of total ${\psi}$ from deep water was associated with the increase of total dissolvable Fe/Mn concentration. Excess total ${\psi}$ activity presented below the euphotic zone might be related to particulate ${\psi}$ concentrated in this water depth. Mean export flux of ${\psi}$ estimated using the steady state model was $867{\pm}246dpmm^{-2}day^{-1}$. Mean export flux of particulate organic carbon, which were estimated by the product of total ${\psi}$ flux and ratio of POC/${\psi}$ ($7.08{\pm}4.27{\mu}molCdpm^{-1}$) in the sinking particles, was $5.9{\pm}3.9mmolCm^{-2}day^{-1}$. These fluxes were similar levels to those in the Weddell Sea during February and March 2008. Export ratios (ThE) relative to the primary production in the euphotic zone were in the range of 3-54% (av. 28%).

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.105-110
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• 1984

Seven seed samples of corn obtained from Kangweon Provincial Office of Rural Development, Kerea were tested for seed-borne fungi, and found that all the samples tested were infected with Fusarium moniliforme to an extent of $6.0{\sim}79.5%$. Severely infected seed samples showed poor germination on blotter. Seed component plating showed that the fungus present not only in tip caps, pericarps and endosperms, but also in embryos. Heavy infection of the fungus caused severe seed rot and seedling blight in soil, but the damage was not severe and many plants grew without any symptoms when the seeds with light infection were sown in soil. However the fungus was frequently detected from inside of the stems of healthy looking seedlings. The results indicate that the fungus transmit from seed to plant systemically. In inoculation experiments, the fungus produced stem rots on corn plants of 110 days old. The cultivar of Hwangok 3 was revealed more susceptible to the fungus than that of Suweon 19.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.634-640
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• 2007

Our previous study suggested that n-3 fatty acid deficiency was associated with significantly reduced spatial learning as assessed by Morris water maze test. Here we investigated an effect of n-3 fatty acid deficiency on rat brain, retina and serum fatty acyl compositions at 15 wks age using a first generational artificial rearing technique. Newborn Rat pups were separated on day 2 and assigned to two artificial rearing groups or a dam-reared control group. Pups were hand fed artificial milk via custom-designed nursing bottles containing either 0.02%(n-3 Deficient) or 3.1% (n-3 Adequate) of total fatty acids as a-linolenic acid(LNA). At day 21, rats were weaned to either n-3 deficient or n-3 adequate pelleted diets and fatty acid compositions of brain, retina and liver were analyzed at 15 wks age. Brain docosahexaenoic acid(DHA) was lower(58% and 61%, P<0.05) in n-3 deficient in comparison to n-3 adequate and dam-reared groups, receptively, while brain docosapentaenoic acid(DPAn-6) was increased in the n-3 deficient group. In retina and serum fatty acid compositions, the decreased precentage of DHA and increased precentage of DPAn-6 were observed. These results suggested that artificial rearing method can be used to produce n-3 fatty acid deficiency in the first generation and that adequate brain DHA levels are required for optimal brain function.