• Journal of the Korea Concrete Institute
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• v.23 no.3
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• pp.265-272
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• 2011

Even though concrete is the most important material for building structures, its intrinsic gray color degrades urban esthetics. In order to improve this problem, coloring methods of mixing pigment in concrete batch and painting the surface of concrete surface have been tried. However, applications of the coloring methods in construction field are difficult due to high cost and low durability. Recently, acid stain agent is emerging as a new coloring method for concrete. It is able to apply a remarkably thin colored layer on a concrete surface from chemical reaction between acid and alkaline solutions. This study has examined the changes and variations of the surface layer of mortar specimen from chemical reaction of acid stained agents. The colors were changed into natural irregular stains according to aging. After the staining, no shape change was found from visible inspections. Microstructure of the colored surface applied with acid stained agent was much rougher than that of original mortar. When the colored layer was compared to original surface, crystals of hydrate such as $Ca(OH)_2$ and C-S-H gel were observed. Surface hardness was same or slightly higher in the colored layer. The value of pH was reduced by approximately 10%, weight contents of elements such as Ca, Si, and Al were low. In the chemical composition of the colored layer, the non-cement based elements of Mn, Cr, and Cu increased. Also, Fe and alkali elements of K and Na increased.

• Korean Journal of Veterinary Research
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• v.32 no.2
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• pp.217-225
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• 1992

Five puppies, 14 days old in the same litter showed acute symptoms such as painful crying, anorexia, abdominal pain and depression with fatal terminations. Necropsy of a puppy revealed hemorrhagic and necrotic foci in the lungs and kidney. The histological lesions were characterized with fibro-necrotizing foci in the lungs, nonsuppurative encephalitis and intranuclear inclusions of liver cells. A cytopathogenic agent was isolated from the thoracic fluid of a dead puppy by cell culture with primary dog kidney cells. The puppies inoculated with the field isolate showed the same clinical signs and lesions as those of the spontaneous cases. Viral particles were observed in suspension of the isolated agent by electron microscopy. The primary dog kidney cells infected with the field isolate showed fluorescent foci against anti-CHV monoclonal antibody after FA stain. On these findings of the disease it was diagnosed as CHV infection. The report signifies the first description of an epizootic of CHV infection in Korea.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.3
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• pp.381-392
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• 2020

The necessity and the importance of the remanufacturing are increasing day by day along with environmental problems. Many studies are being conducted on remanufacturing, but the research for cleaning is much lacking. This study aims to evaluate the effective cleaning method for remanufacturing of start motors, one of the automobile parts. The cleaning process consists of oil stain removal, drying and rust removal processes. In this study, the two processes were conducted except for the drying process which has little influence on cleaning. The methodology for cleaning agent selection, degreasing and rust removal process was presented. For each methodology, five analysis factors were calculated by two-way comparison according to the process, and the values were evaluated quantitatively by substituting them into the evaluation table. In the selection of cleaning agent, neutral system, ultrasonic cleaning in degreasing, and grinding in rust removal were selected as the best cleaning methods.

• Journal of Periodontal and Implant Science
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• v.24 no.2
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• pp.433-440
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• 1994

The purpose of this investigation was to study the efficacy and safety of 6% hydrogen peroxide gel as a daily home tooth bleaching gel. The subjects consisted of 20 male dental students representing a variety of acquired stain and each subject participated for a 4-week period. Tooth color analysis(Shade determination), sulcus bleeding index, probing depth and probing attachment level were done and recorded at baseline and at the end of each week of study. The results indicated that home bleaching gel containing 6% hydrogen peroxide was effective and caused no gingival inflammation. Sulcus bleeding index, probing depth and probing attachment level showed no change. In conclusion, 6% hydrogen peroxide gel is an effective and safe agent for daily home tooth bleaching.

• Applied Biological Chemistry
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• v.48 no.3
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• pp.296-300
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• 2005

Among the root colonizing and plant growth promoting bacteria isolated from the bacterial wilt suppressive soil, five strains were detected to produce siderophores by CAS agar assay. The most effective isolate, TS3-7 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 80% reduction of bacterial wilt disease compared with the control. Significant disease suppression by TS3-7 strain was related to the production of siderophore. Besides iron competition, induction of resistance of the host plant with siderophore was suggested to be another mode of action that suppress bacterial wilt, based on the lack of direct antibiosis against pathogen in vitro. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, TS3-7 stain was identified as Pseudomonas sp. TS3-7.

• Journal of Veterinary Clinics
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• v.15 no.1
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• pp.171-173
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• 1998

A case of peritonitis caused by Actinomycotic spp is reported in a 12-year-old male Siberian tiger. Grossly, the mesentery was markedly thickened and contained numerous 1 to 3 mm diameter, white to yellowish foci. Fibrous adhesion showing tumorous thickening was also noted between the mesentery and abdominal organs. Histologicallyi the thickened mesentery and masses consisted of necrotic center with bacterial colonies surrounded by eosinophilic club (Splendore-hoeppli), neutrophils, macrophages, a few Iymphocytes and fibrosis. The bacterial colonies stained positvely with Gram's stain but were negative on acid-fast and periodic acid-Schifr method. Howeverr since the bacterial culture was not availablei the definitive causative agent was not able to specified.

• Korean Journal of Bronchoesophagology
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• v.5 no.2
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• pp.164-173
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• 1999

Background : cis-Diamminedichloroplatinum(Ⅱ)(cis-platin) has been exhibited similar to bifunctional alkylating agents in the cell and known as an effective anticancer drug. Although this agent is very beneficial to the cancer patients, it may also damage to the normal cell. Many side effects were developed. Objectives : This experiments was undertaken to pursue the effect of cis-Platin on the mucous variation of the trachea. Materials and Methods : The male of Sprague-Dawley strain were used as and experimental animals. The experimental animals were killed at 1, 3 days and 1, 2 and 3 weeks after the third injection of cis-Platin was administered 1.5mg/kg to intraperitoneal injection at once a week for three weeks. The trachea was fixed to neutral formaline and stained with alcian blue(pH 1.0)-PAS, alcian blue(pH 2.5)-PAS double stains and these preparation observed with light microscope. Results : 1. In the trachea stained with alcian blue(pH 2.5)-PAS double stain, the epithelial cells were constricted in the 1 week, In the 1st day, 3rd day and 1st week, acidic mucopolysaccharide was increased but in the 2nd week, neutral mucopolysaccharide was increase. 2. In the trachea stained with alcian blue(pH 1.0)-PAS double stain, the 1st and 3rd day exhibited sulfa mucopolysaccharide with moderately or weakly positive reaction. In the 1st week the sulfa mucopolysaccharide with strongly positive reaction was increased. In the 2nd and 3rd week, the sulfa mucopolysaccharide with weakly positive and non-sulfa or neutral mucopolsaccharide with negative reaction were modified. Conclusion : It is consequently suggested that cis-Platin induces reversible toxic damage to tracheal cells including goblet cell.

• Korean Journal of Pharmacognosy
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• v.5 no.3
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• pp.147-154
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• 1974

Some crude drugs in ancient literatures have been used as traditional therapeutic agent of leucorrhea mainly caused by Trichomonas vaginalis and Candida albicans. Sixty six kinds of crude drugs in ancient literatures and ten constituents were selected as sample drugs. Trichomycin standard was tested to compare with the above drugs. To determine the anti-fungal effect of these drugs on Candida albicans Yu 1200, a test organism, screening test was conducted. Antifungal activities of crude drug water extracts were observed by means of two test methods : firstly through the agar slant method and secondly the counting chamber method which was used for acknowledged drug agents upon the result of the agar slant method. And in order to improve the fungicidal effect, the organisms were stained with 0.02% methylene blue solution. The results of the above test indicated that Fritillariae Rhizoma has antifungal action in the concentration of 310mcg/ml, Coptidis Rhizoma in 620mcg/ml, Meliae Cortex, Scutellariae Radix both in 5,000mcg/ml. Baicalin, catechol among the pure isolated constituents inhibited in the range of 50mcg/ml. This score was based on 50% inhibition in comparison with amounts of control organisms. Rhei Rhizoma, Mori Radicis Cortex, Linderae Radix, and Amomi globosi Fructus showed the antifungal effect moderately in 5,000mcg/ml, and baicalein and pectolinarin in 50mcg/ml in the limit of between 35% and 50% antifungal activity. Staining with 0.02% methylene blue showed that any of the crude drug extracts was unable to stain the cells, but trichomycin in 0.86unit/ml able to stain 12% of the cells. This result means that crude drugs probably do not have fungicidal but fungistatic action.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.401-420
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• 2001

A novel glucanhydrolase from a mutant of Lipomyces starkeyi(KSM 22)has been shown effective in hydrolysis of mutan, reduction of mutan formation by Streptococcus mutans and removal pre-formed sucrose-dependent adherent microbial film and Lipomyces starkeyi KSM 22 dextranase has been strongly bound to hydroxyapatitie. These in vitro properties of Lipomyces starkeyi KSM 22 dextranase are desirable for its application as a dental plaque control agent. This study was performed to determine oral hygiene benefits and safety of dextranase(Lipomyces starkeyi KSM 22 dextranase)-containing mouthwash in human experimental gingivitis. This 3-week clinical trial was placebo-controlled double-blind design evaluating 1U/ml dextranase mouthwash and 0.12% chlorhexidine mouthwash. A total 39 systemically healthy subjects, who had moderate levels of plaque and gingivitis were included. At baseline, 1, 2 and 3 weeks, subjects were scored for plaque(Silness and $L{\ddot{o}e$ plaque index and plaque severity index), gingivitis($L{\ddot{o}e$ and Silness gingival index), and at baseline and 3 weeks of experiment, subjects were scored for plaque(Turesky-Quingley-Hein's plaque index and plaque severity index), tooth stain(Area and severity index system by Lang et al). Additionally, oral mucosal examinations were performed and subjects questioned for adverse symptoms. Two weeks after pre-experiment examinations and a professional prophylaxis, the subjects provided with allocated mousewash and instructed to use 20-ml volumes for 30s twice dailywithout toothbrushing. All the groups showed significant increase in plaque accumulation since 1 week of experiment. During 3 weeks' period, the dextranase group showed the least increase in plaque accumulation of Silness and $L{\ddot{o}e$ plaque index, compared to the chlorhexidine and placebo groups, but chlorhexidine group showed the least increase inplaque accumulation of Turesky-Quingley-Hein's plaque index. As for gingival inflammation, all the groups showed significant increase during 3 weeks of experiment. The dextranase group also showed the least increase in gingival index score, compared to the chlorhexidine as well as the placebo groups. Whereas the tooth stain was increased significantly in the chlorhexidine group, compared to the baseline score and the placebo group since 3 weeks of mouthrinsing. It was significantly increased after 3 weeks in the dextranase group, still less severe than the chlorhexidine group. As for the oral side effect, the dextranase group showed less tongue accumulation, bad taste, compared to the chlorhexidine group. From these results, mouthrinsing with Lipomyces starkeyi KSM 22 dextranase was comparable to 0.12% chlorhexidine mouthwashin inhibition of plaque accumulation and gingival inflammation and local side effects were if anything less frequent and less intense than chlorhexidine, in human experimental gingivitis. All data had provided positive evidence for Lipomyces starkeyi KSM 22 dextranase as an antiplaque agent and suggested that further development of dextranase formulations for plaque control are warranted.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.371-388
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• 2001

A novel glucanhydrolase(DXAMase) from a mutant of Lipomyces starkeyi(KSM 22) has been shown effective in hydrolysis of mutan, reduction of mutan formation by Streptococcus mutans and removal pre-formed sucrose-dependentadherent microbial film and DXAMase has been strongly bound to hydroxyapatitie. These in vitro properties of Lipomyces starkeyi DXAMase are desirable for its application as a dental plaque control agent. This study was performed to determine the adjunctive oral hygiene benefits and safety of dextranase(Lipomyces starkeyi KSM 22 DXAMase)-containing mouthwash when used alongside normal tooth-brushing. This 6-month clinical trial was placebo-controlled double-blind design evaluating 1U/ml dextranase mouthwash and 0.12% chlorhexidine mouthwash. A total 39 systemically healthy subjects, who had moderate levels of plaque and gingivitis were included. At baseline, 1, 3 and 6 months, subjects were scored for plaque accumulation(Turesky modification of Quingley-Hein's plaque index), gingivitis status($L\ddot{o}e$ and Silness gingival index), and tooth stain(Area and severity index system by Lang et al). Additionally, oral mucosal examinations were performed and subjects questioned for adverse symptoms. Two weeks after pre-experiment examinations and a professional prophylaxis, the subjects provided with allocated mousewash and instructed to use 20-ml volumes for 30s twice daily after toothbrushing. All the groups showed significant increase in plaque accumulation since 1 month of experiment. During 6 months' period, the Dextranase mouthwash group showed the least increase in plaque accumulation, compared to the Chlorhexidine mouthwash and placebo groups. As for gingival inflammation, all the groups showed significant increase during 6 months of experiment. The Experimental group(Dextranase mouthwash) also showed the least increase in gingival index score, compared to the Positive control(Chlorhexidine mouthwash)as well as the Negative control(placebo)groups. Whereas the tooth stain was increased significantly in the Positive control group, compared to the baseline score and the Negative controlgroup since 3 months of mouthrinsing. It was significantly increased after 6 months in the Experimental group, still less severe than the Positive control group. As for the oral side effect, the Experimental group showed less tongue accumulation, bad taste, compared to the Positive control group. From these results, mouthrinsing with Lipomyces starkeyi KSM 22 dextranase provided adjunctive benefits to toothbrushing, comparable to 0.12% chlorhexidine mouthwash in inhibition of plaque accumulation and gingival inflammation and local side effects were if anything less frequent and less intense than chlorhexidine, with long-term use of the mouthwash. All data had provided positive evidence for Lipomyces starkeyi KSM 22 dextranase as an antiplaque agent and suggested that further development of dextranase formulations for plaque control are warranted.