• Restorative Dentistry and Endodontics
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• v.27 no.4
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• pp.403-410
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• 2002

Several ways of curing are being tried to improve material's properties and reduce marginal gap. However, all are considering about the pattern of light intensity. It was noted from the preliminary study the change of light wavelength from filter changing may give an impact on material's property and microleakage. The object of this study was to verify the effect of filters with various wavelength width on the microhardness and microleakage of composite resin ; hybrid type of DenFil and submicron hybrid type of Esthet X. Composite resins were cured using 3 kinds of filter; narrow-banded(465-475 nm), mid-banded(430-470 nm), wide-banded(400-500 nm). After the estimation of microhardness. degree of dye penetration and the maximum gap from SEM evaluation were done between 4 groups that showed no difference in microhardness value of the lower surface . The results were as follows : 1 Adequate microhardness could not be gained with a narrow-banded filter irrespective of curing time. At the upper surface, DenFil should be polymerized with middle or wide-banded filter for 20 seconds at least, while Esthet X be col$.$ed with middle or wide-banded filter for 30 seconds at least to get simitar hardness value to control group. 2. There was little dye penetration in enamel margin, but all dentin margins skewed much more dye penetration irrespective of curing conditions. Although there was no statistical difference, groups cured with mid-banded filter for 40 seconds and with wide-width filter for 20 seconds showed relatively less dye penetration. 3. It was revealed from the SEM examination that group cured with wide-banded filter had the smallest gap without statistical significance. Spearman's rho test showed that the correlation between the results of dye penetration and SEM examination was very low. From these results, it could be concluded that curing with wide-width filter would be better than the other techniques, even though the curing technique using mid-width filter seems to have its own unique advantage.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.334-342
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• 1989

The Bacillus stearothermophilus cdd gene encoding cytidine deaminase (cytidine/2'-deoxycytidine aminohydrolase; EC 3.5.4.5) was isolated through shot gun cloning by oomplementation of an E. coli cdd mutation. Primarily 3.0 kbp of the exogenote was cloned into the Pstl site of pBR322 (pJSC101). By subsequent deletion and subcloning from the insert of pJSC101 with cdd$^+$ and tetracycline resistancy, about 1.35 kbp of the EcoRI$_1$/PstI$_2$ fragment containing the cdd gene was isolated as pJSC201. The minicell experiment revealed a molecular mass of 33,000 dalton for polypeptide from the cloned DNA fragment complementing the cdd gene. From the lacZ fusion of 550 bp fragment of the EcoRI$_1$/AuaI as a putative promoter region, the transcription direction of the cdd gene on pJSC201 is from EcoRI towards the PstI sites, When the cdd gene was expressed in B. subtilis ED4O (cdd$^-$, pyr$^-$) by transformation with the E. coli-B. subtilis shuttle vector, the gene expression occured more efficiently than in E. coli and the gene appears to be stably maintained in B. subtitis as well as in E. coli.

• Journal of The Korean Association of Information Education
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• v.17 no.2
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• pp.101-113
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• 2013

The rapid spread of smart devices initiated by the launch of iPhone and the development of state-of-the-art communication technology have opened up a new chapter for today's age, accelerating a paradigm shift. It is defined as 'the smart era' that is characterized by a DNA of mobile. The meaning of the term 'smart' depends on in which field it is used and who uses it, but the term is basically based on 'human being,' namely people. Accordingly, people should take the initiative in this smart era, and what only people can do will become more important for that reason. In addition, there will be a drastic progress in today's technology, which is expected to make human life more convenient and to even make it possible to read human sentiment and emotion. Such social changes have affected education as well, and the education sector is making preparations for the introduction of 'smart education,' as there is a consensus that an absolutely new paradigm shift is mandatory. Smart education is not merely to introduce smart devices, ICT technology and SNS in education. New competent people are required in globalization age, and smart education is to attempt a new education to nurture new competent people. In this study, 4C (that were creativity, collaboration, contents and curation) were suggested as the key factors of smart education, and in which direction smart education should be led in our country was discussed.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.425-431
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• 1996

Human neutrophil elastases (HNElastase, EC 3.4.21.37), a causative factor of inflammatory diseases, are regulated by plasma proteinase inhibitors, alpha-proteinase inhibitor and ${\alpha}_2-macroglobulin$. Under certain pathological conditions, however, released enzymes or abnormal function of inhibitors may cause various inflammatory disease. NSAIDs have been clinically applied for treatment of inflammatory diseases. Inhibition of cyclooxygenase is a known mechanism of action of NSAIDs in the treatment of inflammatory disease. In in vitro experiments, HNElastase was inhibited by naproxen, phenylbutazone, and oxyphenbutazone, but ibuprofen, ketoprofen, aspirin, salicylic acid, and tolmetin did not inhibit elastase. HNElastase was also inhibited by chelating agents, EDTA & EGTA, and tetracyclines. Removal of divalent metal ions by EDTA caused inhibition of elastase, and reconstitution of the metal ions recovered the enzyme activity to a certain level. Frequencies and contours in the Raman spectra of various conditions of human neutrophil elastase undergo drastic changes upon partial removal and/or reconstitution of calcium and zinc ions. The metal ion content dependent activities and change of the contour of the Raman spectrogram suggest us that the mechanism of action of a chelator or chelator-like agents on neutrophil elastase may be related to the conformational change at/or near the active site, especially -C=O radical or -COOH radical.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.343-352
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• 2018

This study was conducted to identify the factors influencing patient safety behavior and performance of infection control in nursing students. This study was a descriptive survey based on data collected from August 28, 2017, to September 22, 2017 from 174 third and fourth year nursing students at E university located in S city of Gyeonggi. The collected data were analyzed using the PASW 23.0 program to conduct an independent t-test, one-way ANOVA, post-hoc Scheffe's test, Pearson's correlation, and multiple regression. The average scores of patient safety behavior and performance of infection control were $4.00{\pm}0.55$ and $4.31{\pm}0.50$, respectively. Patient safety behavior and performance of infection control showed a strong positive correlation. Patient safety behavior was positively influenced by confidence levels of patient safety and awareness of the infection control, and the explanatory power of the model (R2)[ED highlight - should this be R2? If so, change throughout the paper.] was 55.1%. Predictors of the performance of infection control were patient safety knowledge, confidence levels regarding patient safety, and awareness of infection control, and the R2 was 68.1%. Common factors influencing patient safety behavior and infection control performance were patient safety confidence and development of effective clinical practicum education programs to increase confidence in patient safety and infection control.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.48-57
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• 2020

This study examined the influence of the quality of work life on the organizational effectiveness and customer orientation in 119 paramedics. This study also offers basic data for improving the quality of emergency medical services in the future. A survey was conducted from February 3. 2019 through May 7, 2019, on 308 male and female fire officers in Daegu, North Gyeongsang Province. The collected data was analyzed using SPSS 20.0 version, and frequency analysis, correlation analysis and multiple regression analysis were carried out. First, there was a positive correlation among the QWL of the 119 paramedics, their OE and CO. Second, the QWL (personal, management dimension) of the 119 paramedic's was a factor that affected OE and job satisfaction. Third, the QWL (personal, management dimension) of the 119 paramedics had an impact on the CO. (ED note: please check all this and it was not clear. It may be correct now.)Forth, the impact of the OE of the 119 paramedics on the CO exerted a significant influence on the OE and job satisfaction. Given the findings of the study, the QWL of 119 paramedics should be improved to heighten paramedics' welfare to promote the quality of emergency medical services.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2786-2793
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• 2009

Recently, the development and spread of the new recyclable energy becomes urgent because of the depletion of fossil fuel and strengthening the environmental regulation. To recovery from the waste out of the many new recyclable energies has been proved as the most favorable when the potential value of energy source is compared. The RDF from the waste has been approved as the most economical method out of the other methods. However, the toxic gases (HCl, Dioxin etc) and heavy metals generated during the burning of the industrial wastes have been pointed out as problems. The PVC, alkali metal chloride, and alkaline earth metal chloride are major materials for emitting the chlorine and chlorine compounds have the problem such as the erosion on the heat collection device. This research has analyzed the heavy metal components containing in the industrial waste, and the concentration of Cl and S in the industrial waste generated in B industrial complex are slightly high than that of the A industrial complex. The results can be used to discuss the origin of inorganic components in industrial waste and utilized as a base data to improve the performance of the RDF as fuel.

• YAKHAK HOEJI
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• v.40 no.6
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• pp.727-733
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• 1996

2-(Allylthio)pyrazine is effective in selectively suppressing constitutive and inducible expression of cytochrome P450 2E1. The effect of 2-(allylthio)pyrazine against potentiat ed chemical injury was studied in rats. Vitamin-A pretreatment of rats substantially increased carbon tetrachloride hepatotoxicity, as supported by an ~4-fold increase in serum alanine aminotransferase (ALT) activity. Concomitant pretreatment of rats with 2-(allylthio)pyrazine at the daily dose of 200mg/kg resulted in a 76% decrease in vitamin-A-potentiated hepatotoxicity, which supported the possibility that 2-(allylthio)pyrazine protects the liver against chemical-induced hepatic injury by the mechanism associated with Kupffer cell inactivation. Pyridine pretreatment caused substantial enhancement in carbon tetrachloride hepatotoxicity. 2-(Allylthio)pyrazine treatment of rats reduced the pyridine-potentiated toxicity in a dose-dependent manner. Animals treated with both pyridine and 2-(allylthio)pyrazine prior to intoxicating dose of CCl$_4$ resulted in 85% and 47% decreases in pyridine-increased triglycerides and cholesterol levels in the liver. The protective effect of 2-(allylthio)pyrazine on the DNA strand breakage induced by benzenetriol was assessed by measuring the conversion of supercoiled ${\Phi}x$-174 DNA to the open relaxed form. 2-(Allylthio)pyrazine blocked the benzenetriol-induced conversion of supercoiled DNA to open circular form in a dose-dependent manner. The presence of 2-(allylthio)pyrazine at the doses from I to 10mM in the incubation mixture containing 5 ${\mu}$M benzenetriol completely protected benzenetriol-induced DNA strand breakage with the EC50 for the 2-(allylthio)pyrazine blocking being noted as ~220 ${\mu}$M, whereas allyl disulfide exerted protecting effect at relatively high concentrations (i.e. ~850 ${\mu}$M), suggesting that 2-(allylthio)pyrazine effectively scavenges the reactive oxygen species. These results provide evidence that 2-(allylthio)pyrazine blocks vitamin A- or pyridine-potentiated CCl$_4$ hepatotoxicity and that the agent is active in protecting DNA by scavenging the reactive oxygen species.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.103-111
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• 2020

This study investigated how the awareness about marriage, the value of children, and the motivation for childrearing influences childbirth will in nursing students. The data was collected from May 1 to May 30, 2019, and 248 data samples were finally used for analysis. The collected data was analyzed using the SPSS /WIN 22.0 program. Descriptive statistics, Pearson's correlation coefficients, t-tests, ANOVA, Scheffe's test and multiple regression analysis were all calculated. The average of awareness about marriage was 3.39±.38, the average of the value of children was 2.72±0.39, the average motivation of childrearing was 2.73±0.78 and the average of childbirth will was 3.12±0.48. The childbirth will according to the general characteristics, was significantly different according to age (F=6.002, p=.003). Among the awareness about marriage, conservative view on marriage(r=.207, p=.001), active view on marriage(r=.226, p<.001), instrumental view on marriage(r=.181, p=.004), and motivation of childrearing(r=.283, p<.001) showed positive correlation ed with childbirth will. Childbirth will was negatively correlated with passive view on marriage (r=-.292, p<.001), and the value of children (r=-.226, p<.001). The factors affecting childbirth will of the study subjects were age(β=.155, p=.007), passive view on marriage(β=-.383, p<.001), motivation of childrearing (β=.315, p<.001), and the explanatory power was 23.6%. According to this study, it is necessary to confirm the effects of developing an intervention program and applying this program to improve the decisions of nursing students concerning marriage and having children.

• Journal of fish pathology
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• v.21 no.1
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• pp.45-56
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• 2008

This study was conducted to find out biological responses of bivalves exposed to organotin compound.The results of the study confirmed that tribultyltin chloride (TBTCl) induce reduction of survival rate andburrowing activity, and histopathological feature in the foot structure of the equilateral venus, Gomphinaveneriformis. The experimental period was 36 weeks. The experimental groups consisted of a control and 3TBTCl exposure groups (0.4, 0.6, 0.8 ym TBTCl L'). The survival rate and burrowing activity were record-ed daily. For histological analysis, foot tissues were fixed in Bouin' s fluid and then stained H-E stain, AB-PAS (PH 2.5) reaction and Masson's trichrome stain after having serially sectioned the tissue by paraffinmethod at thickness of 4-6 ym. The survival rate was not significantly different between the control andexposure groups for 20 weeks, but in 0.8 Um TBTCl L', it was on the decreased ever since the exposure. Theburrowing activity was not significantly different in the exposure group compared to the control up to 12weeks, but in 0.6 and 0.8 ym TBTCl L', it measured the lowest level after 20 weeks. The foot is composedof the epidermal layer, connective tissue, and muscular layer. The epidermal layer is composed of simplecolumnar, cuboidal epithelia and mucous cells. The cilia were well developed on the apical surface ofepithelium, Circular, longitudinal and transverse muscle bundle were well developed in the muscular layer.The majority mucous cells showed blue color (542c) when it subjected to AB-PAS (PH 2.5) reaction. Nohistopathological alterations in the foot were observed up to 12 weeks. After 20 weeks of exposure to 0.8 (anTBTCl L'', the foot samples of exposed G. veneriformis showed disappearance of cilia and striated borderpartially and extension of hemolymph sinus. The mucous cell increased in the marginal of foot. At 28-weekof exposure to 0.4 ym TBTCl L', it observed weekly acid (564c), neutral (264c) and mixed mucous cell. At36-week of exposure to 0.6 ym TBTCl L', it showed fragmentation of the muscle and collagen fiber bundle,and also diappearance of cilia on epithelia and edema of epithelium in 0.8 ym TBTCl L''.