• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.5
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• pp.217-224
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• 2008

A stoichiometric mixture of evaporating materials for $ZnIn_2Se_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $ZnIn_2Se_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $400^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $ZnIn_2Se_4$ single crystal thin films measured from Hall effect by van der Pauw method are $9.41\times10^{16}cm^{-3}$ and $292cm^2/v{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $ZnIn_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=1.8622eV-(5.23\times10^{-4}eV/K)T^2/(T+775.5K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $ZnIn_2Se_4$ have been estimated to be 182.7 meV and 42.6 meV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $ZnIn_2Se_4/GaAs$ epilayer. The three photo current peaks observed at 10 K are ascribed to the $A_{1}-$, $B_{1}-exciton$ for n = 1 and $C_{27}-exciton$ peaks for n = 27.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.76-83
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• 1999

Studies were conducted during 2 months from May of 1997 to evaluate the effects of pig manure compost(PMC) on soil microbial flora. To do so, a field experiment of Chinese cabbage(Brassica campestris L.) was conducted in a randomized block design on a sandy loam soil and microbial floral characteristics in soils were analyzed. Treatments to control included the application of PMC at (A) $8Mg\;ha^{-1}$CM-8), (B) $29Mg\;ha^{-1}$(CM-2,9), and (C) $57Mg\;ha^{-1}$(CM-57), and of chemical fertilizer(D) at $320N-80P_2O_5-200K_2O\;kg\;ha^{-1}$(NPK). In each treatment, the rhizosphere and non-rhizosphere soils were tested for the analysis of microbial populations. The populations of bacteria, actinomycetes, and fungi increased in soils with the applications of PMC and chemical fertilizer, but that of Bacillus sp. decreased. However, the population of fluorescent Pseudomonas sp. was reduced in NPK plots only. With increasing application rates of PMC, the number of colony forming units(cfu) of bacteria (Pseudomonas sp. and actinomycetes) and fungi increased. in all PMC-treated plots, the population density peaked at early growth stage for bacteria(including Bacillus sp.), at late growth for fluorscent Pseudomonas sp., and at harvest for fungi and actinomycetes. The rhizosphere effect was greatest for fluorscent Pseudomonas sp. As the application rates of PMC increased, Total N, organic matter, available phosphate, and exchangeable -K, -Ca, and -Mg increased compared to control, but soil pH was lowered. In NPK plots, EC was 3.4-fold and exchangeable K was 5-fold higher than control.

• Journal of Bio-Environment Control
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• v.27 no.2
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• pp.125-131
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• 2018

The effect of 1-methylcyclopropene (1-MCP) in the storability of kimchi cabbage at cold storage condition was investigated. Kimchi cabbage (Brassica campestris L. cv Ryouckgwang) was divided four groups, forced air cooling (FAC), FAC + 0.03 mm linear low density polyethylene liner (Liner), $FAC+2{\mu}L{\cdot}L^{-1}$ 1-MCP (1-MCP), and FAC + 1-MCP + Liner. After each treatment kimchi cabbage was stored at $2^{\circ}C$, 95% RH. Quality parameters were weight loss, soluble solids content (SSC), firmness, and color ($CIE\;L^*$, $a^*$, $b^*$, chroma, hue angle). Weight loss during storage was showed significant difference by Liner treatment. In particular FAC + 1-MCP + Liner treatment showed 12.5% reduction after 6 weeks of storage period and minimized the weight loss rate compared to other treatments. SSC of kimchi cabbage was $2.5^{\circ}Brix$ at harvest and FAC + 1-MCP + Liner treatment maintained the SSC until 3 weeks, while in other treatments gradually were increased. The firmness of kimchi cabbage was 24.0 N immediately after harvest and the firmness at harvest time tended to be maintained at 22.6 N after 6 weeks of storage in FAC + 1-MCP + Liner treatment. During the storage period, the color change of the kimchi cabbage leaf can be confirmed by $CIE\;a^*$ and hue angle value. 1-MCP treatment alone did not affect the color change, however 1-MCP + Liner treatment was able to maintain the chromaticity at harvest time while minimizing the change of $CIE\;a^*$ and hue angle. These results suggest that 1-MCP treatment is not effective for the storage of kimchi cabbage but can be maintained for up to 6 weeks when treated with Liner.

• Food Science and Preservation
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• v.21 no.6
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• pp.815-823
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• 2014

This study was carried out to investigate the quality characteristics of muffins with added Pholiota adiposa powder. Muffins were prepared with different amounts of Pholiota adiposa powder (in 0, 2.5, 5, 10, and 15% ratios to the flour quantity). For analyzing the quality characteristics during the manufacturing of muffins, the pH, moisture content, dough density, height, specific volume, baking loss, texture, color, antioxidant activity, total polyphenol content, and sensory test results were determined. As the Pholiota adiposa powder content increased, the moisture content of the muffins decreased from 26.72 to 22.56%. The hardness of the muffins was increased with increasing Pholiota adiposa powder content, with the muffins with 15% Pholiota adiposa powder the hardest among all the samples. The inner color of the muffins, particularly the L and b values, decreased with increasing powder content compared to those of the control, but the a value increased. As the Pholiota adiposa powder content increased, the antioxidant activity and total polyphenol content of the muffins also increased. In the sensory evaluation, the muffins with 5% Pholiota adiposa powder showed higher values than the control and the other samples in all aspects, showing that 5% Pholiota adiposa powder could be incorporated into muffins to meet the taste and functional needs of the consumers.

• Tuberculosis and Respiratory Diseases
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• v.61 no.3
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• pp.256-264
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• 2006

Background: An acute lung injury(ALI) is characterized by the recruitment, activation, and apoptosis of inflammatory cells, numerous products released by inflammatory cells such as reactive oxygen species, inflammatory mediators, and a variety of proteolytic enzymes. It was reported that bacterial infections in diabetics showed impaired PMN functions such as reduced PMN respiratory burst and decreased microbicidal activity in inflamed tissue. However, the effect of the proteinase - inhibitor (MMP-9 vs TIMP-1) in ALI in diabetics is unclear. This study evaluated the differences in the expression of MMP-9 and TIMP-1 after the stimulation of endotoxin in a rat model. Methods: Six-week-old male Sprague-Dawley rats were classified into normal, DM, LPS and DM+LPS groups. The peripheral blood, BAL fluids, and lung tissues were obtained from individual rats. The MMP-9 activity was measured by gelatin zymography and the TIMP-1 level was measured by Western blotting. Results: The total BAL cells of the DM-LPS groups were significantly lower than the LPS groups (p < 0.01). The MMP-9 activities in the serum were higher in the DM+LPS groups than in the other groups. The MMP-9 activities in the BAL fluids were significantly higher in the DM+LPS group than in the normal and diabetic rats (p < 0.05). TIMP-1 expressions in the BAL fluids were significantly lower in the DM+LPS group than other groups (p < 0.05). The ratio between MMP-9 and TIMP-1 in the BAL fluids was significantly higher in the DM+LPS groups (p < 0.05). Conclusion: In ALI in diabetics the higher MMP-9 activity and lower TIMP-1 level are believed to prolonged and intensify the course of inflammation.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.332-340
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• 2009

In this study, the thermal insulation effectiveness of the greenhouse insulators by the installation methods was investigated to find the right installation way of the insulation materials. Physical properties of the insulators such as thickness, air transmissivity, apparent density, ultraviolet rays cutoff ratio, reflectance, thermal conductivity, moisture absorptivity were evaluated and the insulation ability of the insulators were measured by the module experiments. For the same insulator, the insulation ability of the case with the outward direction of the black colored face, i.e., with the inward direction of the white colored face, was better than that of vice versa. The case of the black colored both surfaces was better than the case of the white colored both surfaces. For aluminium reflection material, the case with the outward direction of the lustre face, i.e., with the inward direction of the non-lustre face, was better than that of vice versa. For the same material with the inner thin polyethylene foam (or polyester) and the chemical wool, the case with the outward direction of the inner thin polyethylene foam (or polyester), i.e., with the inward chemical wool, was better than that of vice versa. Addition of the inner thin polyethylene foam increased the insulation effect very much.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.101-108
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• 2005

Because the stone cultural properties located outdoors, they have been altered and deteriorated in external appearance due to environmental factors such as acid rain, extreme change in temperature, and salts. Damage to stone cultural properties is accelerated particularly due to recent industrial development and environmental pollution. An experimental study was conducted to evaluate the effect of environmental contaminants on the weathering of granite. And as part of the developing of conservation method, $TiO_2$ catalyst was prepared and tested. When fresh granite was dipped into the salt and acid solutions, dissolution rate of eight minerals (Si, Mg, Ca, Na, K, Fe, Mn, Al) are abruptly increased at initial stage of reaction and then increased steadily until 100 cycles. After salt and acid solution experiments, the mineral compositions of the granite surface were lower then that of the fresh granite and density of the weathered granite was steadily decreased from $2.60\;g/cm^3$ to $2.56\;g/cm^3$, but Poissions ratio and absorption ratio were slightly increased. It was expected at stone cultural assets could be weathered by salts and acid rain. In the case of $TiO_2$ was coated to the granite, the dissolution rate of minerals and absorption ratio of $TiO_2$ coated granite were decreased. Therefore, the $TiO_2$ coating method tested in this study considered to be a viable method to assist in the conservation of stone cultural properties from environmental contaminants.

• Radiation Oncology Journal
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• v.9 no.1
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• pp.47-52
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• 1991

From April,1983 through April,1989, we have treated histologically proven 21 patients with oligodendroglioma using 6 MV linear accelerator at the Division of Radiation Therapy, Kangnam 51. Mary's Hospital Catholic University Medical College. These are 8% of the irradiated 246 primary brain tumors during the same period. To investigate influencing factors on the survival of irradiated U patients with oligodendroglioma, we analyzed the cerebral location of the involvements, initial symptoms, CT findings and survival rates, retrospectively. One case was lost to follow up and excluded from survival data. Of the 28 patients, thirteen were male and 8 female. Ages ranged from 5 to 68 years with a median age of 38 years. Radiation doses varied from 3900 cGy to 0480 cGy and were given for 5 to 8 weeks. All but one were supratentorial. The involvement of the frontal and parietal lobes were 10 (48%) patients in each and temporal lobe in 8 (38.1%). Histological diagnosis was made by stereotactic biopsy in 3 and postoperatively in 18. The type of surgery was divided into partial, subtotal and total resection in 7,9 and 2 cases respectively. In 6 cases, chemotherapy was also tried during or after radiation therapy. Major presenting symptoms were headache, cerebral motor, nausea & vomiting and epilepsy in 18,12, 7 and 5 respectively in decreasing order. In CT analysis, low density (02%), cystic mass (33%), calcifiestion (66%) and positive contrast enhancement (42.8%) were observed as the highest frequency. Mean survival duration after radiation therapy was 38 months (K-M methods). We could not achieve statistically significant factors influencing on the survival rate after radiation therapy for oligodendrogliomas by one or two tail test.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.15-23
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• 2000

Streptococcus salivarius is a normal inhabitant in the human oral cavity. Streptococcus salivarius 119 in this study was isolated from the oral cavity of child and identified, and its action mechanism on the formation of denal plaque by Streptococcus matans was studied. 1. The optical density of absorbance at 550 nm was 0.327 in the culture of Streptococcus mutans in disposable cuvette, whereas being 0.119 in the combined culture of Streptococcus mutans and Streptococcus salivarius 119. 2. The mean weight of produced artificial plaque on the wires in the beaker was 84.7mg in culture of Streptococcus mutans only, whereas being reduced to 12.3mg in the combined culture of Streptococcus mutans and Streptococcus salivarius 119. 3. When Streptococcus mutans was cultured in the media containing culture supernatant of Streptococcus salivarius 119 in BHI broth, the mean weight of produced artificial plaque was 100.5mg on the wires, whereas being reduced to 20.4mg in the media containing culture supernatant of Streptococcus salivarius 119 in BHIS broth. 4. The viable cells of Streptococcus oralis and Streptococcus salivarius 119 were $4.8\times10^7\;and\;7.5\times10^8$ per ml respectively after each culture, wheras being $4.2\times10^7\;and\;5.8\times10^7$ per ml in the combined culture of Streptococcus oralis and Streptococcus salivarius 119. 5. The polymer produced by Streptococcus salivarius 119 was glucan on the thin layer chromatography. 6. The glucan produced by Streptococcus salivarius 119 was water-soluble glucan containing $1\rightarrow6$ linkages as the main linkage on the thin layer chromatography. These results suggested that isolated Streptococcus salivarius 119 inhibited the formation of artificial plaque by the production of water-soluble glucan.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.213-217
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• 2007

LPS induces the synthesis of several inflammatory cytokine, chemokine, NO and inflammation in the liver of rats. The purpose of this study was to investigate the preventive effects of Rubus coreanum Miquel (RCM) In lipid metabolism. RCM of 100 mg/kg concentration was intraperitoneally administered into rats at dose of 1.5ml/kg for 20 days. On the day 21, 1.5ml/kg of LPS was injected 4 hours before anesthetization. We examined the lipid-related functions by measuring the levels of triglyceride (TG), total cholesterol (TC), total lipid (TL), high-density lipoprotein cholesterol (HDL-C) in serum and malondialdehyde(MDA) in liver tissue. The results showed that LPS treatment increased the values of TG, TC, TL and MDA, decreasing that of HDL-C. But RCM pretreatment decreased the high values of TG, TC, TL and MDA to the low values and increased the low value of HDL-C to the high value. These results suggested that RCM could be used as the potential candidate for the lipid metabolism natural supplement.