• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.468-475
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• 2015

Nonylphenol is one of endocrine disruptors, as structurally stable, hydrophobic compounds exhibit high condensability and long-lasting in the natural environment. The purpose of this study was to determine the toxic effects of nonylphenol on Daphnia magna. In acute toxicity test, D. magna was exposed for 48 h at concentrations of 0, 10, 18, 32, 56 and $100{\mu}g\;L^{-1}$ nonylphenol. In chronic toxicity test, D. magna were exposed through water for 21 days at concentrations of 0, 1.0, 1.8, 3.2, 5.6 and $10{\mu}g\;L^{-1}$ nonylphenol. Acute toxicity was assessed on the basis of immobility, while chronic toxicity was assessed on the basis of fecundity. The acute toxicity test on nonylphenol was showed that the values of 24 h and 48 h $EC_{50}$ were $25.0{\mu}g\;L^{-1}$ and $13.7{\mu}g\;L^{-1}$, respectively. In chronic test, fecundity was reduced significantly at $5.6{\mu}g\;L^{-1}$ of nonylphenol. These results indicated that nonylphenol have some hazard for acute or chronic toxicity to freshwater invertebrate organism.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.90-90
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• 2003

체세포 핵이식에 의한 복제기술은 매우 낮은 성공률 나타내고 있어 실용화에 지장을 초래하고 있다. 이것은 후생적인 유전현상인 reprogramming이 불완전하게 이루어지기 때문인 것으로 추측되어지고 있다(Reik et al., Theriogenology 2003, 59: 21-32; Han et al, Theriogenology 2003, 59: 33-44). 체세포 핵이식 후에 태아사망의 원인이 태반의 비정상적인 기능과 관계가 있는 것으로 추정되는데 복제시 태아사망의 원인을 찾기 위해 본 연구를 시행하였다. 한우에서 체세포 복제 후 임신 말기에 태아가 사망한 태반조직 3개와 IVF 수정란 이식 후 동일한 시기에 제왕절개술을 실시한 태반조직 2개를 실험에 이용하였다. 태반 protein을 Two-Dimensional electrophoresis와 Mass spectrometer를 이용하여 분석 비교하였다. IPG-system을 이용하여 pH 4~7, pH 6~9에서 1차 전기영동을 한 후, 8~l6%의 SDS-PAGE gel에 2차 전기영동을 실시하였고 G-250 Coomassie로 염색하였다. gel 이미지는 Malanie III program을 이용하여 분석하였다. 전체 gel에서 약 1800개의 구분 가능한 protein spot이 나타났다. pH 4~7 범위에서 양적으로 차이나는 것 15개 중 복제한우 태반에서 증가되는 protein spot 5개와 감소하는 protein spot 10개를 골라 protein identification을 실시하였다. MALDI-TOF-MS를 이용하여 동정한 결과 phosphatidylinositol transfer protein-$\alpha$와 interleukin-18 등의 protein이 복제태반에서 발현이 증가되었고, 복제한우에서 발현이 감소되는 것으로는 vimentin, Rho-GDI-$\beta$, TRAST $\beta$-chain, ovarian sterol carrier protein 2, triosephosphate isomerase, tropemyosin beta chain, Aldose reductase 등으로 나타났다. 이러한 protein들은 inositol 지질 신호전달과 면역시스템, 세포분열, 산소 운반, steroidogenic 세포에서의 콜레스테롤 이동, 촉매 작용, 대사 작용 등에 중요한 역할을 하는 것으로 알려져 체세포 복제에 의한 태아사망 원인은 태반에서 이러한 protein들의 비정상적인 발현에 기인된 것으로 추정된다.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.573-582
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• 2003

According to the survey map, the altitudes of up and down the Ansungchon were 242m and 49m accordingly. The width of the river was 4m at upperstream and became wider, lam at midstream and 114m at downstream. Water pH of the Ansungchon was measured variously in the range of 6.0-7.9 according to the surveyed times and areas. The water pH measured during June through August decreased continually and suddenly increased at the end of October. Phragmites iaponica, a major species of the fresh water emergent anchored hydrophytes, was surveyed mostly in the area of upperstream, Phragmites communis, Miscanthus sacchariflorus and Typha orientalis were surveyed in the areas of midstream and downstream, and Zizania latifolia was found in all areas of the river. The total of 101 taxa dividing into 32 families, 71 genera, 88 species, and 13 varieties have been inhabited in these areas. Among the inhabited plants, Poaceae was 21.8%, which appeared in the highest percent. Compositae was 20.8%, and Polygonaceae was 11.9%. In the surveyed areas, herbaceous plants were 95.1% and mostly occupied, and woody plants were 4.9％. Among the herbaceous plants, perennial plants were 52.5%, and annual and biannual plants were 28.7% and 13.9% accordingly. Naturalized plants dividing into 8 families and 18 genera have been found in the surveyed areas. The number of the naturalized plants increased from upperstream to downstream as the environmental disruption became worse. Only 2.5% of the total naturalized plants were appeared in up, 17.7% in midstream, and 28.6% in downstream. Shannon-Weiner's index for the degree of diversity was 2.898-3.666 in the area of upperstream, but 3.708-4.135 in downstream, which was little higher.

• Journal of Sericultural and Entomological Science
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• v.32 no.2
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• pp.118-120
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• 1990

A mulberry field and 3 graftage nurseries in Puyo were flooded for 2 to 5 days in 1987 to investigate flood damage. The effect of fertilization upon fall yield in previously flood fields was also studied. The results were : 1. Graftage which received 2 days of flood were alive with decaying leaves submerged under water. Graftages submerged completely for 5 days died, whereas those whose top appeared above the water lived. Graftages which were knocked down by water and scratched by sand, following washing by a fire engine, died. 2. Mulberry trees flooded for 5 days were alive when tops were above the water. 3. Mud soil carried by the flood and deposited on the mulberry had a pH of 6.43, organic matter 2.4%, and available phosphorus of 124ppm. The original sandy soil of the mulberry field had a pH of 5.52, organic matter 0.3%, and available phosphorus of 467ppm. Mud, as a clayey soil with higth fertility, may play a role in soil building. 4. Mulberry from the flooded field showed 3.4% higher yield with additional fertilization than no fertilization. This suggests nitrogen a mobile element, was lost in the flood.

• The Korean Journal of Pain
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• v.21 no.1
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• pp.38-43
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• 2008

Background: Spinal stenosis and herniated intervertebral discs are the principal causes of lumbosacral radiculopathy. This study was conducted to compare the therapeutic value and duration of pain relief of fluoroscopic guided transforaminal epidural steroid injections (TFESIs) in patients with refractory radicular leg pain. Methods: Between August 2006 and March 2007, 87 patients (H group: patients with herniated intervertebral disc, S group: patients with spinal stenosis) who met the inclusion criteria were treated with fluoroscopic guided TFESIs. Prior to treatment, the VAS and ODI scores were determine to evaluate the degree of pain and level of disability. The degree of pain relief was then assessed 1 month after treatment with the TFESIs and graded as excellent (no residual pain), good (improvement of pain symptoms by more than 50%), fair (improvement of pain symptoms by less than 50%) and Poor (no improvement of pain). In addition, the duration of pain relief was evaluated by regular outpatient visits for 6 months, and by telephone interviews after 6 months. Results: The H and S group both had excellet results at 1 month after treatment with TFESIs showing improvements of 44.1% and 20.8% respectively. However this difference was not significant between groups. In addition, a duration of pain relief greater than 6 months was achieved in 32.4% of the patients in the H group and 37.7% of those in the S group. Conclusions: TFESIs had a similar degree of therapeutic effectiveness and duration of pain relief in patients with spinal stenosis and herniated intervertebral discs.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.5
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• pp.572-579
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• 2006

Accurate heat release analysis based on the cylinder pressure trace is important for evaluating combustion process of diesel engines. However, traditional single-zone heat release models (SZM) have significant limitations due mainly to their simplified assumptions of uniform charge and homogeneity while neglecting local temperature distribution inside cylinder during combustion process. In this study, a heat release analysis based on single-zone model has been evaluated by comparison with computational simulation result using Fire-code, which is based on multidimensional model (MDM). The limitations of the single-zone assumption have been estimated, To overcome these limitations, an improved model that includes the effects of spatial non-uniformity has been applied. From this improved single-zone heat release model (Improved-SZM), two effective values of specific heat ratios, denoted by ${\gamma}_V$ and ${\gamma}_H$ in this study, have been introduced. These values are formulated as the function of charge temperature changing rate and overall equivalence ratio. Also, it is applied that each equation of ${\gamma}_V$ and ${\gamma}_H$ has respectively different slopes according to several meaningful periods during combustion progress. The heat release analysis results based on improved single-zone model gives a good agreement with FIRE-code results over the whole range of operating conditions of target engine, Hyundai HiMSEN H21/32.

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.709-717
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• 2002

Hypoxemia is known to induce various physiological changes which can result in alteration in drug pharmacokinetics. To examine the effect of acute moderate hypoxemia on metoclopramide (MCP) pharmacokinetics, a continuous 14-hour infusion of MCP during a normoxemic, hypoxemic and subsequent normoxemic period was conducted in eight adult sheep. Arterial blood and urine samples were collected to examine the effects on the pharmacokinetics of MCP and its deethylated metabolites. MCP and its mono- and di-deethylated metabolites were quantitated using a GC/MS method. Steady-state concentrations of MCP were achieved in each of the three periods. During hypoxemia, MCP plasma steady-state concentration increased significantly from 50.72$\pm$1.06 to 63.62$\pm$1.79 ng/mL, and later decreased to 55.83$\pm$1.15 ng/mL during the post-hypoxemic recovery period. Total body clearance ($CL_{TB}$) of MCP was significantly decreased from 274.2$\pm$48.0 L/h to 205.40$\pm$28.2 L/h during hypoxemia, and later restored to 245.8$\pm$44.2 L/h during the post-hypoxemic period. Plasma mono-deethylated MCP concentration (32.78$\pm$1.73 ng/mL) also increased, compared to the control group (21.20$\\pm$1.39 ng/mL), during hypoxemia and subsequent normoxemic period. Renal excretion of MCP and its metabolites was also decreased during hypoxemia, while urine flow was increased with a concomitant decrease in urine osmolality. Thus, the results indicate that acute moderate hypoxemia affects MCP pharmacokinetics.

• Journal of Microbiology and Biotechnology
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• v.24 no.7
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• pp.959-968
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• 2014

The changes in the ${\beta}$-glucosidase activity, total phenolic contents, isoflavone contents, and antioxidant activities during the fermentation of cheonggukjang by Bacillus amyloliquefaciens MJ1-4 with and without garlic were investigated. The levels of total phenolic and isoflavone-malonylglycoside, -acetylglycoside, and -aglycone contents increased, whereas the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and ferric reducing/antioxidant power (FRAP) assay results increased, but isoflavone-glycoside levels decreased during cheonggukjang fermentation. The levels of total phenolic and total isoflavone contents and the antioxidant activities were higher in cheonggukjang fermented without garlic (CFWOG) than in cheonggukjang fermented with garlic (CFWG) after 24 h of fermentation, but they were lower in CFWOG than in CFWG after 72 h of fermentation. In particular, the highest levels of total phenolic, daidzein, glycitein, and genistein were present at concentrations of 15.18 mg/g, $264.4{\mu}g/g$, $16.4{\mu}g/g$, and $31.1{\mu}g/g$ after 72 h of fermentation in CFWG, showing 82.89% in DPPH radical scavenging activity, 106.32% in ABTS radical scavenging activity, and 1.47 ($OD_{593nm}$) in FRAP assay, respectively. From these results, we suggest that the high antioxidant activity of CFWG might be related to the markedly higher levels of total phenolic contents, isoflavone-malonylglycosides, -acetylglycosides, and -aglycones achieved during fermentation.

• The Korean Journal of Ecology
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• v.21 no.5_1
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• pp.465-473
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• 1998

This study was carried out to investigate the developmental process of plant community during the secondary succession and changes of soil properties in the burned areas lapsed 28 years after the forest fire in Mt.Palgong. The forest fire occurred on March, 1969 and the red pine (pinus densiflora) forest and its floor vegetation were burned down. The results are summarized as follows: the floristic composition of burned and unburned areas were composed of 49 and 48 species of vascular plants, respectively. The dominant species based on SDR4 of the burned sites were Lespedeza maximowicxii(87.75), Carex humilis (62.94), Rhododendron schippenbachii(55.78) and Miscanthus sinensis var.purpurascens (51.94). In contrast, Pinus densiflora (81.17), Quercus serrata (53.58)m Carex humilis (53.11) and Miscanthus sinenis var. purpuracens (52.42) were dominant in the unburned area. The biological spectra showed the $H-D_1-R_5-e$ type in both areas. The indices of similarity (CCs) between the two areas were 0.80. Degree of succession (DS) was 734 in the burned area and 809 in the unburned area. The species diversity (H) and evenness indices (e) in the burned and unburned areas were 2.05, 2.13 and 0.53, 0.55, respectively. Dominance index (C) in the burned and unburned areas were 0.30 and 0.32, respectively. Soil properties such as soil pH, content of organic matter, total nitrogen, total carbon, exchangeable potassium, sodium, calcium, and magnesium in burned area were comparatively higher than those of unburned area. Monthly changes of soil properties were of little significance except for some cases. These results suggest that there was relationship between trend of vegetation recovery and the changes of soil properties after the forest fire. Mixed forestation of fire-resistant species and nitrogen fixation species will be effective for reforestation after the forest fire.

• Journal of Korean Society of Forest Science
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• v.71 no.1
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• pp.74-81
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• 1985

Dimension analysis was used to estimate biomass and net primary production(NPP) in a 36-year-old Japanese red pine (Pines densiflora S. et Z.) natural forest in Kangwondo. Best estimation was made by the equation model of $Wt=aD^bH^c$ where Wt is weight in kg, D is DBH in cm, and H is total tree height in m. Total aboveground biomass was estimated at 198.82 t/ha. Organic matter was distributed in the Japanese red pine stand as follows ; bolewood 68.8%, live branches 16.5%, bolebark 5.4%, foliage 4.6%, dead branches 3.7%, and cones 0.6%. Net primary production was estimated at 15.87 t/㏊/yr and was distributed: bolewood 44.5%, live branches 30.9%, foliage 14.1%, current twig 7.1%, and bolebark 3.3%. Leaf efficiency was estimated at 1.876. The power equation for biomass and IVPP yielded similar results as the results for Pines densiflora in Japan.