• Food Science and Preservation
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• v.17 no.3
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• pp.405-409
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• 2010

Surface cleaning is both essential and troublesome when a consumer seeks to eliminate soil attached to the surface of fresh ginseng because all ginseng purchased in the market is covered with soil, reflecting the post-harvest situation. To facilitate ginseng use at home, a fresh-cut type of ginseng is required. As a first step toward production of such ginseng, several washing and dipping treatments were investigated with respect to surface cleaning and reduction of microbial populations on fresh ginseng. In terms of microbial distribution on the surface of fresh ginseng, higher levels of viable bacteria (6.63 log CFU/each) and fungi (5.12 log CFU/each) were present on the rhizome head than on other regions of the root. Of the washing treatments tested, hand-brushing was effective for surface cleaning and to reduce microorganism levels on fresh ginseng, but use of a high-pressure water spray followed by hand-brushing was optimally effective. To further reduce the levelsof microorganisms on the surface of fresh ginseng after washing, additional dipping treatments in 70% (v/v) ethanol and electrolyzed acidic water (at pH 2.3) were somewhat effective but showed no significant differences compared with other dipping treatments tested, including a 3 ppm ozone solution, a 200 ppm sodium hypochlorite solution, or hot water at $50^{\circ}C$.

• Restorative Dentistry and Endodontics
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• v.27 no.4
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• pp.421-431
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• 2002

C-shaped canal configuration is very difficult to treat because that clues about preoperative canal anatomy cannot be ascertained from clinical crown morphology and limited information can be derived from radiographic examination. This study was done to get more informations about the root and canal configuration of C-shape root by 3-dimensionally reconstructing for the purpose of enhancing success rate of endodontic treatment. 30 mandibular molars with C-shaped root were selected. Six photo images from occlusal, apical, mesial, distal, buccal, lingual directions and radiographic view were taken as preoperative ones to compare them with 3-D image. After crown reduction to the level of 1-2mm over pulpal floor was performed, teeth were stored in 5.25% sodium hypochlorite solution for the removal of pulp tissue and debris. They were cleaned under running water, allowed to bench dry and embedded in a self-curing resin. This resin block was serially ground with a microtome (Accutom-50, Struers, Denmark) and the image of each level was recorded by digital camera (FinePix S1-pro, Fuji Co., Japan). The thickness of each section was 0.25mm. Photographs of serial sections through all root canal were digitized using Adobe Photoshop 5.0 and then minimum thickness of open and closed sites were measured (open site is the surface containing occluso-apical groove closed site is oppsite). After dizitization using 3-D Doctor (Able software Corp, USA). 3D reconstruction of the outer surface of tooth and the inner surface of pulp space was made. Canal classsification of C-shaped roots was performed from this 3-D reconstructed image. The results were as follows : 1. Most C-shape rooted teeth showed lingual groove (28/30). 2 According to Vertuccis' calssification, type I, II, III, IV, VII were observed. but also new canal types suck as 2-3-2, 1-2-3-2. 2-3-2-1, 2-3-2-3 were shown. 3 There was little difference in minimum thickness on coronal and apical portions, but open site were thinner than closed site on mid portion. Conclusively, 3D reconstruction method could make the exact configurations of C-shape root possible to be visualized and analyzed from multi-directions. Data from minimum thickness recommend cleaning and shaping be more carefully done on dangerous mid portion.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.281-286
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• 2010

The objective of this study was to analyze the microbial populations in the raw ingredients of kimchi and their changes during an automated commercial manufacturing process. High population numbers of total aerobic bacteria, lactic acid bacteria, Leuconostoc sp., and yeast were detected in garlic, ginger, red pepper powder and this result revealed that these ingredients were the major source of microbials in kimchi. Additionally, during the salting process of Chinese cabbage, rapid microbial growth was observed and the consecutive washing process was determined to be ineffective, lowering the microbial count by only one log reduction. Yeast was also detected in various ingredients. These results strongly suggest that, in order to lower the microbial population numbers in kimchi, the side-ingredients and salting process should be subjected to the appropriate sanitization or sterilization processes at the HACCP level. Beside, treatment of salted Chinese cabbage with sodium hypochlorite solutions after the salting step is recommended. To inhibit yeast growth, appropriate chemical treatment and approval of additive uses to control microbials should be considered. These experimental results and suggestions will be used to improve the kimchi manufacturing process in factories.

• Restorative Dentistry and Endodontics
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• v.21 no.1
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• pp.202-217
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• 1996

The purpose of this study was to compare the degree of microleakage of Glass-Ionomer root canal sealer possessed several enviable properties with that of the other sealers and to evaluate clinical performance. One hundred twenty single-rooted teeth were used in this experiment. The teeth were cleaned mechanically and immersed for 24 hours in 5.25% sodium hypochlorite and clinical crowns then were removed. After the root canals were instrumented using a step-back technique. one hundred twenty single-rooted teeth were divided into five groups of 24 in each. Group 1 : Tubli-Seal(Kerr Co., MI, U.S.A/ZOE-based), lateral condensation Group 2 : Sealapex(Kerr/Sybron, Romulus, MI/ $Ca(OH)_2$-based), lateral condensation Group 3 : AH 26(De Trey Co., Zurich Switzerland/Resin-based), lateral condensation Group 4 : Ketac-Endo(ESPE GMBH & CO. KG Seefeld:oberbay. Germany/ Glass Ionomer Cement-based), lateral condensation Control group : no sealer. lateral condensation And then. the root canals were obturated by lateral condensation technique with gutta-percha and experimental sealers. The control group were obturated without sealer. The teeth were placed in a vacuum chamber for 15 minutes and immersed 2% methylene blue under vacuum for 15 minutes. The teeth were passively stained for 1 week and 2 weeks and were cleared and evaluated for linear dye leakage using Tool maker's microscope(${\times}200$). The results were as follows: 1. There were statistically significant differences in the degree of dye penetration between the control group and experimental groups(p<0.05). 2. In the experimental groups, Sealapex($1.2871{\pm}0.9180mm$) exhibited the lowest mean value of dye penetration, followed by Ketac-Endo($1.4432{\pm}0.8082mm$), AH 26($1.5030{\pm}0.7752mm$) and Tubli-Seal($1.6458{\pm}1.0292mm$)(p>0.05). 3. There were statistically significant differences in the variation of microleakage between 1 week and 2weeks in Tubli-Seal and Seal apex groups (p<0.05). 4. The degree of dye penetration of all groups were increased as the time elapsed and AH 26 showed the lowest variation(+0.11) and Tubli-Seal(+ 1.03) showed the highest variation (p<0.001).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5644-5651
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• 2014

Propolis is an extremely safe natural antimicrobial substance that has been reported to have powerful antibacterial efficacy. The aim of this study was to evaluate the inhibitory effects of propolis against Candida albicans (C. albicans). Propolis was collected from the honey bee Apis mellifera. The strain of C. albicans was cultivated overnight in liquid media incubated at $37^{\circ}C$. The antimicrobial activity was investigated using phosphate buffered saline (PBS), 3% sodium hypochlorite (NaOCl), 0.1% chorhexidine (CHX), and propolis extracts ($5{\mu}l/ml$, $10{\mu}l/ml$). C. albicans were sensitive to 3% NaOCl, 0.1% CHX, and propolis ($5{\mu}l/ml$, $10{\mu}l/ml$) with zones of inhibition of 15, 14.5, 16, and 17 mm, respectively. The CFU of PBS, 3% NaOCl, 0.1% CHX, $5{\mu}l/ml$ and $10{\mu}l/ml$ of propolis led a 1, 7, 7, 5 and 7-log reduction. Among the groups tested, C. albicans was most sensitive to $10{\mu}l/ml$ of propolis, which showed the largest inhibition zones. Therefore, propolis can be a new antimicrobial therapy for oral mucosa disease in traditional medicine.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.729-734
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• 2008

The higher valence state of iron i.e., Fe(VI) was employed for the treatment of Cu(II)-EDTA in the aqueous/waste waters. The ferrate(VI) was prepared through wet oxidation of Fe(III) by sodium hypochlorite. The purity of prepared Fe(VI) was above 93%. The stability of Fe(VI) solution decreased as solution pH decreased through self decomposition. The reduction of Fe(VI) was obtained by using the UV-Visible measurements. The dissociation of Cu(II)-EDTA complex through oxidation of EDTA using Fe(VI) and subsequent treatment of organic matter and metal ions by Fe(III) reduced from Fe(VI) in bench-scale of continuous flow reactor were studied. The removal efficiencies of copper were 69% and 79% in pH control basin and reactor, respectively, at 120 minutes as retention time. In addition, Cu(II)-EDTA in the reactor was decomplexated more than 80% after 120 minutes as retention time. From this work, a continuous treatment process for the wastewater containing metal and EDTA by employing Fe(VI) as muluti-functional agent was developed.

• Journal of the Korean Chemical Society
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• v.39 no.5
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• pp.364-370
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• 1995

The catalytic oxidations of several olefins in $CH_2Cl_2$ have been investigated using non-redox metalloporphyrin (M=Ga(III), In(III), Tl(III)) complexes as catalyst and sodium hypochlorite as terminal oxidant. Porphyrins were $(p-CH_3O)TPP,\;(p-CH_3)TPP,\;TPP,\;(p-F)TPP,\;(p-Cl)TPP\;and\;(F_20)TPP$ (TPP=tetraphenylporphyrin), and olefins were $(p-CH_3O)-,\;(p-CH_3)-,\;(p-H)-,\;(p-F)-,\;(p-Cl)-\;and\;(p-Br)styrene$styrene and cyclopentene and cyclohexene. The substrate conversion yield was discussed according to the substituent effects of metalloporphyrin and substrate, and the radius effect of non-redox metal ion. The conversion yield of substrate by changing the substituent of TPP increased in the order of $p-CH_3O$ < $p-CH_3$ < H < p-F < p-Cl, which was consistent with the sequence of $4{\sigma}$ values of TPP. But the substituent effect of substrate on the conversion yield decreased with increasing the ${\sigma}^+$ values on substrates in the order of p-CH3O > p-CH3 > H > p-Cl > p-Br. For the oxidation of several olefins, the complexes of In(III)- and Tl(III)-porphyrins turned out to be more active catalysts than Ga(III)-porphyrin.

• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.80-86
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• 1978

This study was carried out in order to know the effect of T. T. C. reaction on antibiotics, cleanser, disinfectants, pH, acidity and station of culture a bacterial Streptococcus thermophilus was used to 2.3.5-triphenyl tetrazolium chloride reduction test for the detection of residual antibiotics in milk were tested. The results obtained were summarized as follows. 1. The T. T. C. reaction was most sensitive in the group of penicillin as 0.02~0.05 IU and also it was less sensitive in Streptomycin and various broad antibiotics except Vibramycin, Synthomycin and Teramycin but it was least sensitive in Streptomycin group. 2. For ther T. T. C. reaction test on cleanser, the positive reaction was appeared above 0.7% of Hi-Ti and 0.1% of NaOH solution respectively. 3. For the T. T. C. test reaction on disinfectants, the positive reaction was occured on 200~500 ppm solution of sodium-hypochlorite and chloride-lime, 0.15~0.35% solution of phenol, cresol and Iode-K. 4. The optimum temperature was $35{\sim}37^{\circ}C$ and proper culturing time was 12 to 18 hours for propagation culturing. 5. The suspect positive reaction was tested above pH 5.0 and the positive reaction was appeared above 0.21% of acidity.

• Ecology and Resilient Infrastructure
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• v.5 no.3
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• pp.111-117
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• 2018

Disinfection of ballast water using chlorine dioxide was investigated under various initial microorganism contents, dose concentrations and pH values. Kinetics of microorganism inactivation and byproduct generation of chlorine dioxide treatment were compared with the chlorine treatment. Results of treatments with chlorine dioxide concentrations of 0 to $10mg\;Cl_2/L$ showed that The optimum concentration of chlorine dioxide required for disinfection of ballast water was 1 mg/L. The difference among the second order reaction constants for bacterial disinfection at pH 7.2 to 9.2 for chlorine dioxide was less than 5% for both bacteria. This result implied that the bactericidal effects of chlorine dioxide was independent of the pH in the examined range. On the other hand, the inactivation kinetics of chlorine for E. coli and Enterococcus decreased by 17% and 25%, respectively, when pH increased from 7.2 to 9.2. The bactericidal power of chlorine dioxide was superior to sodium hypochlorite above pH 8.2, the average pH value of sea water. Furthermore, treatments of chlorine dioxide generated less harmful byproducts than chlorine and had a long-term disinfection effect on bacteria and phytoplankton from the results of experiment for 30 days. Chlorine dioxide would be a promising alternative disinfectant for ballast water.

• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.535-542
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• 2002

The purpose of this study was to evaluate the effect of EDTA irrigant according to application time and temperature. 31 human mature extracted teeth with a single canal were sectioned with microtome in 3mm thickness and gained 62 samples of root canals. They were distributed randomly into 6 groups of 10 specimens each and control group of 2 specimens. Each specimen was prepared with GT rotary file (Dentsply, Maillefer Co., Swiss) and irrigated with 3 ml sodium hypochlorite every minute. Then smear layer was removed with EDTA solution (PULPDENT$^{\circledR}$, PULPDENT Co., USA.) except two control specimens. Specimens of each group were irrigated with 17% EDTA. The time and temperature of application were as follows : (Table omitted) All specimens were split longitudinally and prepared for examination by scanning electron microscopy. A set of reference micrographs was used to award a debris score as follows: 0 = no smear layer, all tubules clean and open; 1 = no superficial smear layer, tubule openings visible, but some contain debris plug or soft tissue remnants: 2 = moderate smear layer, some tubules open and others closed; 3 = heavy smear layer, most/all tubule openings obscured. Results were evaluated with Kruskal-Wallis test to determine whether there was statistically significant difference among six groups. Pairs of groups were analyzed using the Student-Newman-Keuls Method and Mann-Whitney test. The results were as follows : 1. Control specimens showed heavy smear layer at the canal walls 2. Among the groups applied with EDTA for 2 minutes, group 1 showed the heaviest smear layer, and there was statistically significant difference between group 1 and the other groups(p<0.05). 3. Among the groups applied with EDTA for 5 minutes, group 4 and group 6 showed smear layer but there was no significant difference between them. 4. Among the groups applied with EDTA for the same temperature, group 1 showed heavier smear layer than group 4, and there was statistically significant difference(p<0.05). 5. Among the groups applied with EDTA for the same temperature, group 2 showed heavier smear layer than group 5 and group 3 showed heavier smear layer than group 6. But there was no statistically significant difference among them. From the results above, it could be concluded, EDTA solution is effective in removing of smear layer when it is applied for 5 minutes. If EDTA is applied for 2 minutes, it should be applied above room temperature.