• Title/Summary/Keyword: GCF

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Matrix metalloproteinase-8 and substance P levels in root canal exudates of nonvital teeth (근관 삼출액에서의 기질금속단백분해효소-8과 substance P의 수준에 관한 연구)

  • Shin, Su-Jung;Lee, Woo-Cheol;Lee, Jae-Il;Baek, Seung-Ho;Kum, Kee-Yeon;Shon, Won-Jun;Bae, Kwang-Shik
    • Restorative Dentistry and Endodontics
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    • v.36 no.3
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    • pp.196-202
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    • 2011
  • Objectives: The aim of this study was to investigate levels of matrix metalloproteinase-8 (MMP-8) and substance P (SP) in root canal exudates during root canal treatment (RCT) of nonvital, painful teeth. Materials and Methods: Patients scheduled for nonsurgical RCT were prospectively selected; the study was performed after obtaining informed consent from the patients and was approved by the Institutional Review Board for Clinical Research of Gangnam Severance Hospital, Yonsei University (3-2008-0118). Canal exudates samples were collected using sterilized paper points from teeth scheduled for RCT across three different time periods. MMP-8 and SP levels were measured using enzyme-linked immunosorbent assay (ELISA). Data were analyzed using a mixed model analysis and the Pearson correlation analysis (p < 0.05). Results: MMP-8 and SP levels in GCF were decreased during RCT (p < 0.0001), and they showed a weak positive correlation to each other (p < 0.05). Patients' subjective pain levels and the response from percussion test were significantly related to SP level. Conclusions: This study demonstrated that periradicular inflammation endodontic origin can elevate SP and MMP-8 levels in root canal exudates. Interestingly, SP level of canal exudates showed a possibility of being used as an indicator of pain due to periapical pathosis.

Artificial Sea Ice Increasing to Mitigate Global Warming (지구 온난화 경감을 위한 인공해빙증가)

  • Byun, Hi-Ryong;Park, Chang-Kyun
    • Journal of the Korean earth science society
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    • v.36 no.6
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    • pp.501-511
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    • 2015
  • This study suggests a method of alleviating global warming by the increase of the Earth surface albedo through Artificial Sea ice Increasing (ASI) over the Available Freezing Areas (AFA). The method is developed based on the fact that the large sea surface area in or near the Arctic and the Antarctic has no ice even though both water and air temperatures are below zero and the artificial sea ice generation is thus available. The mean energy of $0.85Wm^{-2}$, which was suspected of adding to the earth by the global warming effect was calculated to offset at once when the sea ice area about $4.09{\times}10^6km^2$ was additionally increased. In addition, three techniques for producing ice plates on the sea surface (using ships, installation apparatus, and floating matter such as Green Cell Foam) for ASI were proposed. According to the result of simple analysis using the energy balance model, when ASI was maximally operated only for 3 months (September, October, and November) over AFA, it is expected that the annual mean temperature of earth surface would be decreased about $0.11^{\circ}C$ in the following year. On the other hand, in case of generating the artificial sea ice in all four seasons, a risk of triggering snowball earth was detected.

Determination of Amitrole in Water Samples by Evaporation and GC/MS (증발법과 GC/MS를 이용한 수질 시료 중의 Amitrole의 분석법 연구)

  • Yoon, So Hee;Hong, Ji Eun;Pyo, Hee Soo;Park, Song Ja
    • Analytical Science and Technology
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    • v.16 no.6
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    • pp.483-487
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    • 2003
  • Amitrole is well-known as a non-selective herbicide and it is able to cause contamination of driking water as well as pollution of ground water and surface water. However, it is difficult to extract from water because it has a high solubility for water whereas a low solubility for general organic solvents. This method is described for the determination of amitrole in water samples by GC/MS. After evaporation of 10 mL water sample by a vacuum evaporator, amitrole was derivatized with isobutyl chloroformate (iso-BCF) on room temperature for 15~20 min. As a result, the sensitivity for GCfMS was improved as N-isobutoxycarbonyl amitrole derivative was formed. The linearity of the calibration curve showed good as 0.997. The recoveries were obtained more than 94.9% and relative standard deviations were less than 2.8% at $1.0{\mu}g/L$, $10.0{\mu}g/L$ and $100.0{\mu}g/L$. The limit of detection showed $0.1{\mu}g/L$ with a signal-to-noise ratio (S/N) of 3.

Evaluating MRV Potentials based on Satellite Image in UN-REDD Opportunity Cost Estimation: A Case Study for Mt. Geum-gang of North Korea (UN-REDD 기회비용 산정에서 위성영상 기반의 MRV 여건평가: 금강산을 사례로)

  • Joo, Seung-Min;Um, Jung-Sup
    • Spatial Information Research
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    • v.22 no.3
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    • pp.47-58
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    • 2014
  • The credible measurement, reporting and verification (MRV) is among the most critical elements in UN-REDD (United Nations programme on Reducing Emissions from Deforestation and forest Degradation in Developing Countries). This study is intended to explore MRV potential in terms of UN-REDD opportunity cost estimation using satellite image for Mt. Geum-gang of North Korea. A visual interpretation were conducted to evaluate MRV conditions by sub-dividing or decomposing the images with different pixel size into a three types of hierarchical tree structure that helps dealing with spatial variability within each subarea. The permanent record of standard satellite remote sensing system demonstrated its capability of presenting area-wide visual evidences of MRV conditions in Mt. Geum-gang (such as the identification of forested area, degradation trends for forest space, three types of hierarchical land-cover and land use tree structure, carbon density in the landscape). Satellite data could be accepted as legally binding proof when it comes to REDD opportunity cost estimation since several cases exist where remote sensing has been used as legal evidence in ICJ (International Court of Justice) and UN resolution. It doesn't seem very difficult to comply with MRV requirements for UN-REDD opportunity cost calculation due to the probative value of satellite data. It is anticipated that this research output could be used as a valuable reference for Korea-based enterprises exploring REDD project sites and the carbon traders to ensure MRV potentials using satellite image in UN-REDD Opportunity Cost estimation.

The Rapid Detection of Pathogens in Organically Grown Vegetables Using PCR-DGGE (PCR-DGGE를 이용한 유기농 채소의 유해 미생물 신속 검지)

  • Kwon, Oh Yeoun;Son, Seok Min
    • Food Engineering Progress
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    • v.15 no.4
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    • pp.370-375
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    • 2011
  • In this study the polymerase chain reaction (PCR) combined with denaturing gradient gel electrophoresis (DGGE) was evaluated as a method permitting the rapid detection of pathogens in fresh originally grown vegetables. A universal primer (341GCf/534r) was selected for its ability to amplify the V3 region of 16S-rRNA genes in their target pathogens (Salmonella typhimurium, Pseudomonas fluorescens, Bacillus cereus, Listeria monoytogenes, Staphyloocus aureus, E. coli). The 194 bp fragments in PCR were successfully duplicated as expected. The amplified fragments of the same size from six different pathogens also showed good separation upon DGGE. The detection limit of PCR-DGGE for six pathogens in fresh-cut lettuces were over $10^{5}$ CFU/g when sampled by stomaching. However, when the sampling method was changed from stomaching to shaking, the detection limit of six pathogens in organic vegetables was shown to increase by over $10^{1}$ CFU/g, but only those of B. cereus were over $10^{3}$ CFU/g. Therefore, PCR-DGGE was shown to be a reliable method for the detection of pathogens in fresh-cut vegetables.