• The Journal of Korean Academy of Prosthodontics
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• v.56 no.2
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• pp.114-119
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• 2018

Purpose: Patients who treated implant immediate loading within a week after implant placement at Wonkwang University Dental Hospital Implant Center were evaluated marginal bone resorption. These retrospective analyses are intended to reinforce the clinical evidence for the implant immediate loading. Materials and methods: Medical history and radiographic data were investigated, which were the patients' who treated implant immediate loading and restoration with provisional prostheses between January 2005 and June 2016, at Wonkwang University Dental Hospital Implant Center. Total number of implants was 70, marginal bone resorption was measured according to implant length, diameter and connection type. To measure marginal bone resorption, periapical radiographs were taken when the implants were placed and after 6 month. Statistical analysis was done in Mann-whitney U test and Kruskal-wallis test with SPSS 22.0 software (P<.05). Results: Mean marginal bone resorption around immediately loaded implants according to implant connection type was shown $1.24{\pm}0.72mm$ in internal hexagon connection type and $1.73{\pm}1.27mm$ in external hexagon connection type. There was no statically significant difference in marginal bone resorption with implant length and diameter. Conclusion: Implants with immediated loading in internal hexagon connection type showed less marginal bone resorption significantly than in external hexagon connection type.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.449-455
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• 2012

Greenhouse and laboratory experiments were conducted to determine the effects of shade treatment and substrate components on plant growth and physiological activity of Taraxacum officinale. Substrates combined with coco peat and perlite (ratio 70 : 30 and 50 : 50, v/v) showed higher growth and yield than their single substrates (p<0.05). Shade treatment also significantly reduced plant height, root length, root diameter, leaf area, chlorophyll content, and fresh weight (p<0.05), compared to no shade. Contents of total phenolics [mg chlorogenic acid equivalents (CAE) $kg^{-1}$ DW] and total flavonoids [mg naringin equivalents $kg^{-1}$ DW] showed higher amounts in shoot parts than root parts of T. officinale, with shade than no shade. The antioxidant potential of the methanol extracts from the plants dose-dependently increased. DPPH (1,1-diphenyl-2-picryl hydrazyl radical) free radical scavenging activity was higher in leaf parts than in root parts of the plants, and no shade than with shade.

• Microbiology and Biotechnology Letters
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• v.28 no.2
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• pp.111-116
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• 2000

Cultural conditions for the production of water-soluble pigment from mycelial culture of Cordyceps scarabaeicola KEFC-C252 and antimutagenic activity of the pigment were investigated. To obtain the maximum productivity of the pigment from mycelial culture of C. scarabaeicola KEFC-C252, the optimized medium was made with 1.5% sucrose, 2.5% yeast extract and initial pH 5.5. C. scarabaeicola KEFC-C252 was cultivated to reach the maximum concentration of the pigment at $26^{\circ}C$ for 108 hrs. C. scarabaeicola KEFC-C252 produced about 1.2 g/liter pigment under the optimized condition. The pigment was isolated from the culture filtrate by ethylacetate extraction, acidic precipitation and crystallization. The isolated pigment was scarlet hexagonal column crystal, and the color of the pigment was changed according to pH of the solution. The pigment showed violet in the alkaline water but showed red color in the acidic water. The pigment showed inhibitory activity against mutagenic activity induced by 4-nitroquinoline N-oxide. Furthermore, the pigment showed inhibitory activity against spontaneous mutation on Salmonella typhimurium TA98 and TAlOO.

• Microbiology and Biotechnology Letters
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• v.28 no.3
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• pp.152-155
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• 2000

Cultural Conditions for the Improvement in Gibberellic Acid Productivity by a Mutant of Gibberellafujikuroi ATCC 12616-Gibberella fujikuroi G-36 . Dh, Young-Jun. Department of Food and Biotechnolog}'r Dongshm Umversity, Naju 520-714, Korea - A mutant Gibberella jujih/roi G- 36 was selected by metagenesis of G/bberella fitjikuroi ATCC 12616 with mutagens such as N-methy1-N'~nitro~N"nitrosoguanidine and hydroxylamine for improving productivity of gibberellic acid. The mutant strain produced gibberellic acid (70 mg/l) more than that of wilde type. A fermentation medium containing glucose, $NH_4N0_3$, $MgS0_4$, $KH_2P0_4$ and trace elements was deve]oped for the maximal production of a gibberellic acid by the mutanL The Guctuating cultural temperature that was vaded from 300e to 20DC resulted in higher GA yield than that of fixed cu1tura] temperature at $28^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.27 no.1
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• pp.31-37
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• 1983

The consumption of atmospheric carbon monoxide by soil was measured under laboratory conditions in different types of soils. Laboratory experiments were performed with humus containing high proportion of organic matter, roadside soils, and humus and roadside soils previously exposed to high concentration of CO by reusing in the experiment. CO concentrations in the 18.2 l-reaction vessel were varied from 2,000 ppm to 24,000ppm to estimate the effectiveness of CO consumption at high level of CO. The uptake of CO by soil was measured by gas chromatography using a TCD detector. The control experiments conducted along with the soil experiments evidently indicated that the potting soil is responsible for CO consumption. Humus showed much higher CO uptake rates compared with the soil taken from roadside. The humus reused in the experiment showed somewhat higher rates(15%) of uptake than the fresh one. The soil's ability to remove CO from the test atmosphere reached a maximum near the CO concentration of 13,000 ppm in the range of $9,000~24,000ppm$. The addition of streptomycin did not influence the removal capacity of soil significantly, whereas 10% saline solution remarkably prevented CO uptake of the humus sample.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.9
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• pp.937-944
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• 2012

The thermodynamic characteristics of a trilateral cycle with water as a working fluid have been theoretically investigated for an electric generation system to recover the waste heat of the exhaust gas from a diesel engine used for the propulsion of a large ship. As a result, when a heat source was given, the efficiencies of energy and exergy were maximized by the specific conditions of the pressure and mass flow rate for the working fluid at the turbine(expander) inlet. In this case, as the condensation temperature increased, the volume expansion ratio of the turbine could be reduced properly; however, the exergy loss of the heat source and exergy destruction of the condenser increased. Therefore, in order to recover the waste exergy from the topping cycle, the combined cycle with a bottoming cycle such as an organic Rankine cycle, which is utilized at relatively low temperatures, was found to be useful.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.501-505
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• 1991

To evaluate the suitability of solid-culm crops for silage, culm characteristics and the variation of solidness in several solid-culm and hollow-culm cultivars of wheat and triticale were examined both in the field and greenhouse. The degree of culm solidness and the voiume of air space in each internodes were measured at heading. The solidness of solid-culm were increased by the development of pith connected with vascular bundles. There was a variation in solidness among the crops tested. The degree of solidness in hollow -culm crops was 14.6% and 15.0% for 'Wonkwang' wheat and 'Shinkihomil' triticale, whereas in solid-culm crops the degree was 77.0-100% for durum wheats, 61. 0-95.8% for bread wheats and 18,7-57,0% for triticales. For 'Golden ball' which had the most solid culms among durum wheats tested higher solidness was observed in the greenhouse than the field, in the high internodes than low ones and in tiller culms than main stems. The solid-culm crops had a smaller air volume in internodes (1.01-2.30ml) than did 'Shinkihomil' (4.85ml) and this characteristics was considered to be advantageous for air removal and lactic fermentation at ensilaging.

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.224-230
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• 1989

For the production of catechol from benzene, bacteria capable of assimilating benzene as a sole carbon and energy source were isolated from soils. Among them, newly isolated strain, KY-114 hay-ing the best ability of producing catechol from benzene was selected and a mutant Pseudomonas sp. HW-103 was developed from Pseudomonas sp. KY-114 by using mutagenesis induced by N-methyl - N'- nitro - N -nitrobo guanidine. The catechol reduction from benzone by Pseudomonas sp. HW-103 was investigated under various conditions. The highest catechol concentration (0.61 g/$\ell$) was obtained in the growth medium (pH 6.5) containing 1% sodium citrate, 0.75% (NH$_4$)$_2$SO$_4$, 0.15% benzene and other minerals at 3$0^{\circ}C$ after incubating of 15hrs. In the catechol production through the reaction with resting rolls, 2.5 g/1 of catechol was produced from 4 g/$\ell$ of benzene after incubation of 10 hrs under the optium conditions, which correponds to 45% of theoretical catechol yield.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.166-185
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• 1983

Aspergillus niger IFO 8541 (NRRL 3112) was investigated through a series of UV rays and N-Methyl-N'-Nitro-N-Nitrosoguanidine (NTG) treatments to induce mutants that produce highly active raw starch saccharifying enzyme, and two mutants with strong enzymatic productivity were obtained. The mutants obtained were investigated for their fungal characters, condition of enzyme production, and other activities. Furthermore, the raw starch saccharifying enzyme was purified and the characteristics of purified enzyme were studied. The results obtained were summarized as follows; 1. The color of conidial head of UV-46 mutant obtained from UV rays treatment was changed to tan type and the gelatinated starch saccharifying enzyme productivity and the raw starch saccharifying enzyme productivity increased up to twice and 1.8 times compared to the productivities of original Aspergillus niger IFO 8541 cultured on the wheat bran, respectively. 2. The conidial head color of NG-41 mutant obtained from NTG treatment became lighter than that of parent strain. The gelatinated starch saccharifying enzyme productivity and raw starch saccharifying enzyme productivity increased about 1.8 times, and twice over the Aspergillus niger IFO 8541 parent strain cultured on wheat bran, respectively. The productivity of ${\alpha}$-amylase increased about 3 times more than the parent strain. 3. Two peaks of glucoanlylase and a peak of ${\alpha}$-amylase were obtained when enzyme solution of mutants and parent strain were passed through DEAE-Sephadex A-50 column chromatography. Glucoamylase I showed only gelatinated starch saccharifying enzyme activity. However, glucoamylase II (raw starch saccharifying enzyme) showed both raw starch saccharifying enzyme activity and gelatinated starch saccharifying enzyme activity. 4. Mutant, UV-46 was strengthened in glucoamylase II productivity and mutant NG-41 was strengthened in ${\alpha}$-amylase productivity. 5. Glucoamylase II of mutants and parent strain were appeared to have the same enzymatic properties. 6. Glucoamylase II of mutants and parent strain were recognized as simple enzyme through electrophoresis. 7. The glucoamylase II crystallized showed rhombic board type. 8. The molecular weight, isoelectric point, optimum pH, and optimum temperature of the glucoamylase II crystallized were estimated as 76,000, 3.4, 3.5 and $60^{\circ}C$, respectively.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.4
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• pp.1-9
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• 2009

This paper investigates inelastic lateral-torsional buckling of stepped beams subjected to uniformly distributed load and end moments. A three-dimensional finite-element program ABAQUS (2007) and a regression program MINITAB(2006) were used to analytically develop new design equation for singly and doubly stepped beams with simple boundary condition. The flanges of the smaller cross-section in the stepped beams were fixed at 30.48 by 2.54 cm, whereas the width and thickness of the flanges of the larger cross-section varied. The web thickness and height of the beams were kept at 1.65 cm and 88.9 cm, respectively. The ratios of the flange thickness, flange width, and stepped length of beam are considered with analytical parameters. Two groups of 27 cases and 36 cases, respectively, were analyzed for doubly and singly stepped beams in the inelastic buckling range. The combined effects of residual stresses and geometrical imperfection on inelastic lateral-torsional buckling of beams are considered. The distributions of residual stress of the cross-section is same as shown in Pi and Trahair (1995) and the initial geometric imperfection of the beam is set by central displacement equal to 0.1% of the unbraced length of beam. The comparisons between results from proposed equations and the results from finite element analyses were presented in this paper. The maximum differences of two results are of 13% for the doubly stepped beam and 10% for the singly stepped beam. The proposed equations definitely improve current design methods for the inelastic lateral-torsional buckling problem and increase efficiency in building and bridge design.