• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.190-198
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• 2021

Human Aichivirus (Aichivirus A; AiV-A) is a positive-sense single-strand RNA non-enveloped virus that has been detected worldwide in various water environments including sewage, river, surface, and ground over the past decade. To develop a method with excellent sensitivity and specificity for AiV-A diagnosis from water environments such as groundwater, a combination capable of reverse transcription (RT)-nested polymerase chain reaction (PCR) was developed based on existing reported and newly designed primers. A selective method was applied to evaluate domestic drinking groundwater samples. Thus, a procedure was devised to select and subsequently identify RT-nested PCR primer sets that can successfully detect and identify AiV-A from groundwater samples. The findings will contribute to developing a better monitoring system to detect AiV-A contamination in water environments such as groundwater.

• Korean Journal of Veterinary Service
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• v.23 no.4
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• pp.341-348
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• 2000

Nowadays we continue to face challenges to the safety of our foods. It seems clear that contaminated meats provide the major route of listeria monocytogenes transmission from the environment to humans. L monocytogenes is the most important species associated with disease in humans among the listeria sp. The current incidence of symptomatic listeriosis caused by L monocytogenes is uncertain. Although the number of reports in the literature on listeriosis are increasing, it is likely that they are actually unrecognized or underreported because of a lack of awareness on the part of some laboratory workers who fail to isolate or identify these organisms. To get the information of sanitary development, we survey various meats (beef, pork, etc) in Kyongbuk area. Samples were collected from local meat shop at Kyongbuk area. Total sixty six case were isolated and identified from one hundreds and seven samples. L innocua was the most abundant in listeria sp. Among U isolates, the number of isolated L innocua was 43 (65.2%). The numbers of isolated L murrayi, L welshimeri, L monocytogenes and L seeligeri were 12(18.2%), 7(10.6%), 3(4.5%) and 1(1.5%), respectively, but L grayi, L iuanouii were not Isolated.

• Journal of Agricultural Extension & Community Development
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• v.6 no.1
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• pp.15-24
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• 1999

There have always been dilemmas between development and environmental conservation throughout the world. Gradually environmental contamination threatens sustainable development and conservation. we try to study on the sustainable development with environmental conservation. One of the instruments to get this goal is Environmental Impact Statement. Environmental Impact Statement has now become a standard tool of decision making in Environmentally Sound and Sustainable Development. The objectives of this study is to explore and suggest some suggestions for improvements of EIA. 1. Identify all criteria and standards that apply to physical and social environmental components and dynamics. 2. Giving attention to the purpose of the criterion and standard, with respect to resource use and quality. 3. Demonstrate the relevance legal, technical, and scientific authority by early planning through construction, operation and maintenance phases. 4. Implement rationales and protocols for the documentation of standard analytical methods, location of sampling points and statistical analysis of data. 5. Establish precise protocols by predictions of environmental impact relevant for established criteria and standards. Reviewing these protocols with relevant legal authorities prior to their implementation is important.

• Journal of Environmental Science International
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• v.17 no.1
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• pp.119-128
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• 2008

Laboratory analytical results of 22 sets of hydrophobic adsorbent coils containing surface soil-vapor and two soil samples collected by conventional intrusive method from each boring location at two active dry cleaning facilities in the State of Illinois, U.S.A, were presented to evaluate the performance of soil-vapor survey. The most critical factor to determine the effectiveness of soil-vapor survey is the distance from the soil-vapor sampling device to the actual contamination, which is a function of soil porosity, permeability, primary lithology, and other geological and hydrogeological site-specific parameters. Also this factor can be affected by the history of contaminant-generating operations. The laboratory analytical results in this study showed longer dry cleaning operation history (i.e., 50 years) and presence of fine sand at the beneath Site B allow the contaminants to migrate farther and deeper over a fixed time compared to Site A(i.e., 35 years and silty clay) so that the soil-vapor survey is not likely the most effective environmental site investigation method alone for Site B. However, for Site A, the soil-vapor survey successfully screened the site to identify the location reporting the highest soil concentration of chlorinated solvents.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.78.1-78.1
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• 2013

The hierarchical model of galaxy formation predicts that galaxy halos contain merger relics in the form of long stellar stream. Thus, tidal substructure of stars around globular clusters, such as tidal tails, could be an essential evidence of the merging scenario in the formation of the Galaxy. From April 2010 to December 2012, we obtained $45^{\prime}{\times}45^{\prime}$ wide-field JHKs near-infrared photometric imaging data for about 20 globular clusters in the Milky Way, and examined the stellar density distribution around globular clusters. Here, we introduce the preliminary results of stellar spatial distributions and radial surface density profiles of four globular clusters. In order to minimize the field star contamination and identify the cluster's member candidates stars, we used a statistical filtering algorithm and gave weights on the CMDs of globular clusters. In two-dimensional stellar density maps, we could found tidal stripping structures for some globular clusters. The orientation of tidal substructure seems to associate with the effects of dynamical interactions with the Galaxy and cluster's orbit. Indeed, the radial surface density profile accurately describes this stripping structures as a break in the slope of profile. The observational results could give us further observational evidence of merging scenario of the formation of the Galaxy.

• Korean Journal of Plant Tissue Culture
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• v.21 no.4
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• pp.221-225
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• 1994

This experiment was conducted to identify the optimal in vitro propagation condition of Cnidii rhizoma (Cnidium officinale Makino). It was effective to reduce contamination and improve regeneration of shoot when shoot tips taken in July were cultured in 1/2 strength Murashige and Skoog medium supplemented with 500 mg/L carbenicillin disodium 1.0 mg/L BA and 1.0mg/L $GA_3$followed by surface sterilization of explant source in solution of 1% sodium hypochlorite for 20 minutes. When shoot tips were 쳐cultured in 1/2 strength MS medium with 0.5 mg/L BA and 60 g/L sucrose, shoot elogation and subsequent multiplication of the formed shoot were favorable than in other media. Regenerants were well rooted in 1/2 strength MS medium containing 3.0 mg/L NAA.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.757-762
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• 2010

Cronobacter is a major foodborne pathogen in powdered infant formula and can lead to serious developmental after-effect and death to infants. The contamination of Cronobacter may be a high risk for the powdered foods. To isolate and identify Cronobacter from the powdered foods such as powdered infant formula and Saengsik in Korea, a conventional culture method, rapid identification system, PCR, and 16S rDNA sequencing were performed. As the results of isolation, seven Cronobacter spp. were isolated from seven out of 102 powdered infant formulas and 41 Cronobacter were isolated from 41 out of 86 Saengsiks. Forty-eight Cronobacter isolates were identified to be C. sakazakii and C. dublenisis by 16S rDNA sequence analysis. Most of the isolates were C. sakazakii and 13% of the isolates were C. dublinesis. One fourth of the C. sakazakii isolates showed different biochemical characteristics of negative nitrate reduction and nonmotility activities compared with the other strains reported previously.

• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.616-624
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• 2015

Flashover of power transmission line insulators due to contamination is a major threat to the reliable operation of power system. This paper deals with the analysis of leakage current characteristics of polymeric insulator using S-Transform technique in order to develop a better diagnostic tool to identify the surface condition of outdoor polymeric insulators. In this work, experiments were carried out on 11 kV silicone rubber insulator under AC voltage at different pollution levels. Moving average technique was adopted to find the trend followed by LC peak at different relative humidity conditions. S-Transform was used to find the relationship between energy and frequency content of the leakage current signal with respect to increase in pollution level over a period of time. From the S-Transform time-frequency contour analysis, point of transition to severe arcing due to increase in pollution and its thershold limit were evaluated. Reported results show that the surface condition of insulators could be easily identified from the S-Transform time-frequency analysis of leakage current signals.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.10
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• pp.1125-1131
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• 2009

O-rings are commonly used in machines as a seal. Due to prolonged use the surface of an O-ring can degrade which can lead to leakage as well as contamination. Damage of O-rings used in vacuum applications such as sputter is caused by various mechanisms. Particles detached from the O-ring may cause significant problems on the performance of the system in the vacuum chamber. Therefore, understanding the tribological behavior of O-rings is important to tackle the damage caused by repeated contact. In this work, FKM rubber was used for friction and wear tests conducted to investigate the tribological behavior of O-rings. A reciprocating type of a tribo-tester was used for the tests. The friction coefficient between the steel ball and the FKM specimen was quite high. Also, in order to identify the wear behavior, the surface of the FKM specimen was characterized using both optical and scanning electron microscopes. Evidence of wear due to adhesion and extrusion could be found. The results of this work will aid in improving the durability of O-rings.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1590-1595
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• 2009

Alternative methods for controlling bacterial endospore contamination are desired in a range of industries and applications. Attention has recently turned to natural products, such as essential oils, which have sporicidal activity. In this study, a selection of essential oils was investigated to identify those with activity against Bacillus subtilis spores. Spores were exposed to 13 essential oils, and surviving spores were enumerated. Cardamom, tea tree, and juniper leaf oils were the most effective, reducing the number of viable spores by 3 logs at concentrations above 1%. Sporicidal activity was enhanced at high temperatures ($60^{\circ}C$) or longer exposure times (up to 1 week). Gas chromatography-mass spectrometry analysis identified the components of the active essential oils. However, none of the major oil components exhibited equivalent activity to the whole oils. The fact that oil components, either alone or in combination, did not show the same level of sporicidal activity as the complete oils suggested that minor components may be involved, or that these act synergistically with major components. Scanning electron microscopy was used to examine spores after exposure to essential oils and suggested that leakage of spore contents was the likely mode of sporicidal action. Our data have shown that essential oils exert sporicidal activity and may be useful in applications where bacterial spore reduction is desired.