• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.228-242
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• 2016

This research was conducted for understanding the evergreen forest community structure of the Bijin Island. The island was worth of vegetational value because of the representative warm temperate species such as Castanopsis cuspidata was distribute there. According to the results of community classification by TWINSPAN and DCA, the Bijin Island evergreen forest were classified by 9 communities, such as C. cuspidata, C. cuspidata-Pinus thunbergii, Neolitsea sericea-Camellia japonica, Platycarya strobilacea, Quercus serrata-Decidus broad-leaved, Alnus firma, P. thunbergii. Due to the C. cuspidata, N. sericea, Ca. japonica etc. were still dominated at canopy and under-canopy layer, so the evergreen forest will be sustain current conditions for a while if there is no artificial disturbances that were caused by human. Pl. strobilacea community will be expected to replace N. sericea and also Q. serrata-Decidus broad-leaved community will be changing caused by mutual competition. Normally, in the way of the succession process of the warm temperate forest, P. thunbergii will be expect via deciduous broad-leaved to evergreen forest such as Machilus thunbergii, C. cuspidata var. sieboldii, and N. sericea. In case of species diversity index, P. thunbergii comm.(1.2739), Q. serrata-Decidus broad-leaved comm.(1.2325), Decidus broad-leaved comm.(1.1807), and A. firma comm.(1.0854) are relatively high, while C. cuspidata and N. sericea-Ca. japonica that was dominated by evergreen species at canopy layer and P. thunbergii that was damaged by fire are relatively low(0.7380~0.8416). Soil pH was 4.72~6.33, electric conductance was 0.035~0.128dS/m, and content of organic matter was 3.4~17.4%.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.619-633
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• 1996

This study was carried out from March 1995 to February 1996 to select suitable vegetation and measures for revegetation on the highway cut-slope in consideration of the surrounding environment in the middle region of Korea. The numbers of revegetation-measures type surveyed were eighteen measures as a whole in descending order of the Seed-spraying measures, Block-sod pitching measures, and Straw-mat mulching measures. The numbers of vegetation species by highway line were 243 in Chungbu, 223 in Jungang, 210 in Kyongbu 2, 199 in Kyongbu 1, 179 in Sohaean, 163 in Seoul circulation. 148 in Shingal-ansan, 141 in Second kyongin and 123 in Kyongin respectively. The highest index of species diversity(H') was in Kyongbu 1-line and the evenness(E') on upper site was greater than that of the lower site. The revegetation measures were selected in consideration of nature of soil, gradient, area and situation, and 83 species were selected as those for revegetation measures in highway cut-slope.

• Journal of Life Science
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• v.16 no.1
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• pp.30-36
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• 2006

Neutrophils are short-lived leukocytes that play a vital role in immune responses to bacteria, yeast, and fungi. This study was performed to investigate the effect of 4-O-methyl-ascochlorin (MAC), an anti-tumor, antibiotic, and anti-fungal prenyl-phenol compound on the spontaneous apoptosis of human neutrophils. MAC time- and dose-dependently accelerated the spontaneous apoptosis of human neutrophils. The effect of MAC on neutrophil apoptosis was blocked by pre-treatment of the neutrophils with specific inhibitors of pancaspase (zVAD-fmk), caspase-8 (zIETD-fmk), or caspase-3 (zDEVD-fmk). The cleavage of procaspase-8 and procaspase-3 was increased by MAC. Mitochondrial permeability, which was measured by the retention of $DiOC_6(3)$, was dose-de-pendently increased by MAC but the change of mitochondrial permeability was not blocked by pretreatment of neutrophils with zIETD-fmk. These results suggest that MAC induces neutrophil apoptosis by caspase-8-dependent but mitochondria-independent manner.

• Korean Journal of Materials Research
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• v.29 no.2
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• pp.92-96
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• 2019

Transition metal oxide is widely used as a water electrolysis catalyst to substitute for a noble metal catalyst such as $IrO_2$ and $RuO_2$. In this study, the sol-gel method is used to synthesize the $Cu_xCo_{3-x}O_4$ catalyst for the oxygen evolution reaction (OER),. The CuxCo3-xO4 is synthesized at various calcination temperatures from $250^{\circ}C$ to $400^{\circ}C$ for 4 h. The $Cu_xCo_{3-x}O_4$ synthesized at $300^{\circ}C$ has a perfect spinel structure without residues of the precursor and secondary phases, such as CuO. The particle size of $Cu_xCo_{3-x}O_4$ increases with an increase in calcination temperature. Amongst all the samples studied, $Cu_xCo_{3-x}O_4$, which is synthesized at 300?, has the highest activity for the OER. Its onset potential for the OER is 370 mV and the overpotential at $10mA/cm^2$ is 438 mV. The tafel slope of $Cu_xCo_{3-x}O_4$ synthesized at $300^{\circ}C$ has a low value of 58 mV/dec. These results are mainly explained by the increase in the available active surface area of the $Cu_xCo_{3-x}O_4$ catalyst.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.105-111
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• 2011

The purpose of this study was to find out the effect of a torrent control structure using customized tetrapods on the forest water quality conservation and management. The study was conducted in the Honggye valley located in Sanchung-gun, Gyungsangnam-do, and stream water quality was compared before and after construction of torrent control structure. After construction of the torrent control structure using customized tetrapods, pH of stream water didn't get out of the range of River water quality standard class I. After construction of the torrent control structure using customized tetrapods, Dissolved Oxygen concentration didn't change, and Electrical Conductivity measurements agreed well within the range of normal clean stream water quality. After construction of the torrent control structure using customized tetrapods, average of total amount of anion was 3.07/2.30~3.60 mg/L, being slightly greater than before construction. Stream water quality after construction of the torrent control structure was similar to before construction. Therefore, it was find out that the torrent control structure didn't affect stream water quality.

• Korean Journal of Metals and Materials
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• v.56 no.12
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• pp.885-892
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• 2018

Molybdenum disulfide ($MoS_2$) based electrocatalysts have been proposed as substitutes for platinum group metal (PGM) based electrocatalyst to hydrogen evolution reaction (HER) in water electrolysis. Here, we studied $MoS_2/CNFs$ hybrid catalyst prepared by electrospinning method with heat treatment for polymer electrolyte membrane(PEM) water electrolysis to improve the HER activity. The physicochemical and electrochemical properties such as average diameter, crystalline properties, electrocatalitic activity for HER of synthesized $MoS_2/CNFs$ were investigated by the Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy (TEM), Raman Spectroscopy (Raman) and Linear Sweep Voltammetry (LSV). The as spun ATTM/PVP nanofibers were prepared by sol-gel and electrospinning method. Subsequently, the $MoS_2/CNFs$ was dereived from reduction heat treatment of ATTM at the ATTM/PVP nanofibers and carbonization heat treatment. Synthesized $MoS_2/CNFs$ electrocatalyst had an average diameter of $179{\pm}30nm$. We confirmed that the $MoS_2$ layers in $MoS_2/CNF$ electrocatalyst consist of 3~4 layers from the Raman results. In addition, We confirmed that the $MoS_2$ layers in $MoS_2/CNF$ catalyst consist of 7.47% octahedral 1T phase $MoS_2$, 63.77% trigonal prismatic 2H phase $MoS_2$ with 28.75% $MoO_3$ through the XRD, Raman and XPS results. It was shown that $MoS_2/CNFs$ had the overpotential of 0.278 V at $10mA/cm^2$ and tafel slope of 74.8 mV/dec in 0.5 M sulfuric acid ($H_2SO_4$) electrolyte.

• Resources Recycling
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• v.31 no.1
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• pp.37-45
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• 2022

The development of the electrical, electronic, and telecommunication industries has increased the share of electricity in total energy consumption. With the enforcement of the Act on the Promotion of the Development, Use, and Diffusion of New and Renewable Energy in 2021, the mandatory supply ratio of new and renewable energy is expected to expand, and the amount of waste cables generated in the stage of replacing and discarding cables used in the industry is also expected to increase. The purpose of this study was to quantify the environmental burden of waste cable recycling through the life cycle assessment (LCA) method. The results showed that the higher the amount of glue contained in the waste cable, the greater was the amount of fine dust and greenhouse gases generated. In addition, by assigning weights to 10 environmental burden items, it was confirmed that the marine aquatic eco-toxicity potential (MAETP) and human toxicity potential (HTP) had the greatest environmental burden. The main causes were identified as heptane and ethanol, which were the glue contained in the waste cable and the cleaning solutions used to remove them. Therefore, it is necessary to refrain from using glue in the cable production process and reduce the environmental burden by reducing the use of waste cable cleaning solutions used in the recycling process or using alternative materials.

• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.318-326
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• 1990

This experiment was conducted to determine the economic housing density levels on caged laying hens The experiment was carried out with 600 ISA Babcock strain of white coder and 450 ISA Brown strain of brown color for production period(21－72 weeks) from May 11. 1987 to June 27. 1988. The levels of housing density was employed 5 or 6 by hen's color from 272 to 920$\textrm{cm}^2$/per hen. The results obtained were summarzed as follows ： 1. Although there were not statistically significant among the housing density levels, The body weight gain for pullet period(14－20 weeks) were in case of white pullet the lowest at the group of high crowding density (272$\textrm{cm}^2$/per pullet) and in case of Brown pullet was the lowest at the group of high crowding density(306$\textrm{cm}^2$/per pullet). 2. Viabillity of pullet from 14 to 20 weeks were more 97% and there urere not statistically significant among the housing density. 3. Viabillity of laying hens was increased as increasing housing density through the etire product period(21－72 weeks) but 453$\textrm{cm}^2$/per hen group(in case of brown hen) showed a significant difference (P＜.05). 4. Rate of egg production through the etire production period(21－72 weeks) were significantly increased by increasing housing density (P＜.05 or .01). 5. Average egg weight through the entire production period(21－72 weeks) was not significantly different among housing density levels at all laying kent 6. In case of white strain, egg mass per hen among treatment during the age of 63－72 weeks were decreased by increasing housing density, meanwhile, in case of brown strain were increased by decreasing housing density during the whole period and there were significant different among the all treatment 7. There were no significant different in feed intake among the all treatment through the entire production period(21－72 weeks) at the white strain laying hens but in case of brown strains, Feed intake were increased by increasing housing density and feeding spece/per hen, and there were significant different among the all treatment 8. Feed requirements per egg at white strain was the highest when the 272$\textrm{cm}^2$/per hen levels and at the brown strains was the highest when the 306$\textrm{cm}^2$/per hen levels, however, among the other treatment were no significant.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.5.2-5
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• 1982

With the improvement of living standard and socioenvironmental change, esophageal stricture due to acetic acid, Hcl, insecticides and lye has led to decrease remarkably. Esophageal stricture has decreased because of immediate treatment and adequate management. However there are still sporadic incidents of esophageal stricture due to inadequate treatment and uncooperation of patients. The authors recently have experienced seven severe cases of esophageal stricture. All six patients were treated with 18-51 French Sippy esophageal dilating bougie. One patient was transfered to thoracic surgery department due to complete esophageal obstruction. Case 1. A 23 year old housewife who ingested Hcl for suicide. After Witzel's operation, she visited to dilate esophageal first constriction stircture due to swallowing difficulty postoperation 2 months later. We were treated successfully. Case 2. A case of esophageal stricuture in the second and third physiologic constriction part. The patient was 51 years old man who ingested lye accidently, and was dilated by bougination. Case 3. The patient was 43 year-old man who ingested acetic acid as a mistake and was treated inadequately at hopsital. Inspite of treatment, esophageal stricture developed at the third physiologic part. We are trying to dilate the esophagues now. Case 4. The patient was 55 year-old woman who had ingested Hcl for the purpose of suicidal attempt. 2 months later gastroduodenal anastomoisis due to pyloric region stenosis, the first physiologic constriction stricture was dilated successfully. Case 5. The patient was 41 year-old woman who ingested Hcl for suicide 4 months ago. There was indwelled orogastric tube for 1 month but esophageal stricture developed at the first and 3rd constriction part. She was treated by using a bougination. Case 6. An athlete 21 year old man, ingested acetic acid 2 spoonful per 3 days by purpose in order to soften the bone for last 14 months. There was complete esophageal obsturction in esophagogram and transferred to the thoracic surgery department. Case 7. A 3 year-old girl was ingested lye at a accident. She had a bougination for 16 months under the general anesthesia for dilation due to whole irregular esophageal stricture. She developed lower esophageal perforation, but healed eventually.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.13.2-14
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• 1982

Otitis media with effusion, described first by Politzer (1867), is closely related with the function of auditory tube, but its etiology and pathogenesis are not clearly defined yet. There are many theories about its pathogenesis including hydrops ex vacuo theory which was most reliable nowadays. In this paper, using cats in experimental animals, hydrops ex vacuo theory was proved and cytological study of the effusion and light microscopic observation of the middle ear mucosa in otitis media with effusion were done. The results were as follows: 1) The effusion was found in all experimental groups after eighteen hours of the auditory tube obstruction. 2) In the cytological study of effusion by smear technic, Polymorpholeukocytes were dominant in earlier days but monoculear cells were soon increased and no eosinophils were found. 3) In the culture of the effusion, no bacteria was cultured. 4) By opeating microscope, hypertrophy of the middle ear mucosa observed especially in the fourteen days after auditory tube obstruction and effusion was most remarkable in the fourteen days, also. 5) By light microscopy, there were epithelial hyperplasia, proliferation of goblet cells, capillaries and infiltration of inflammatory cells which showed same distribution as smear technic.