• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.107-112
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• 2018

The purpose of this study was to investigate the migration levels of lead (Pb), cadmium (Cd) and arsenic (As) from polycarbonate food contact materials into food simulant at different temperatures ($70^{\circ}C$ and $100^{\circ}C$). The method was validated by linearity of calibration curves, limit of detection (LOD), limit of quantification (LOQ), recovery, precision and uncertainty. All of 200 samples, including bottles, cups, containers, ladles, spoons and tongs were purchased from domestic markets and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Mean concentrations of positive samples were higher at $100^{\circ}C$ than $70^{\circ}C$ as showing a dependency of migration temperature. The migration concentrations ranged from not-detected (ND) to $4.67{\mu}g/L$, ND to $0.49{\mu}g/L$L and ND to $2.91{\mu}g/L$ for Pb, Cd and As, respectively, which were far below the migration limits of Korea standards and specifications for food utensils, containers and packages.

• Journal of the Korean Society of Groundwater Environment
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• v.3 no.2
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• pp.51-59
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• 1996

In case waste disposal site is to be constructed close to the underground facilities such as LPG storage cavern which is completely maintained by groundwater pressure, it is generally requested that the possibility on leachate contamination of cavern area be reviewed and the countermeasure, if it is estimated cavern area is severely affected by leachate, be taken into consideration. Prediction was performed and leachate control plan was made using by analytical and the numerical analysis on the leachate migration which is likely to happen at the area between the proposed waste disposal site and the underground LPG storage cavern located at the U petrochemical complex. Analytical solutions were obtained by the conservative mass advection-diffusion equation and the effect of advection and dispersion factor on the leachate migration was reviewed through peclet number calculation and the functional relationship between the factors and leachate transport velocity was established, which leads to enable us to predict the leachate transport velocity without difficulties when different parameters (factors) are used for analytical solution. Numerical solutions were obtained by FEM using AQUA2D which is for the simulation of groundwater flow and contaminant transport. 3-D discrete fracture models were simulated and fracture flow analysis was performed and feasibility study on the water-curtain system was conducted through the fracture connectivity analysis in rock mass. As results of those analyses, it was interpreted that the leachate would trespass on the LPG storage cavern area in 30 years from the proposed wate disposal site and the vertical water-curtain system was effective mathod for the prevention of leachate's migration further into the cavern area.

• Clinical and Experimental Pediatrics
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• v.48 no.6
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• pp.580-587
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• 2005

New evidence is emerging that airway smooth muscle(ASM) may act as an immunomodulatory cell by providing pro-inflammatory cytokines and chemokines, polypeptide growth factors, extracellular matrix proteins, cell adhesion receptors and co-stimulatory molecules. ASM can promote the formation of the interstitial extracellular matrix, and potentially contribute to the alterations within the extracellular matrix in asthma. In addition, extracellular matrix components can alter the proliferative, survival, and cytoskeletal synthetic function of ASM cells through integrin-directed signaling. Increased ASM mass is one of the most important features of the airway wall remodeling process in asthma. Three different mechanisms may contribute to the increased ASM mass : cell proliferation, increased migration and decreased rate of apoptosis. The major signaling pathways of cell proliferation activated by ASM mitogens are those dependent on extracellular signal-regulated kinase and phosphoinositide 3'-kinase. The key signaling mechanisms of cell migration have been identified as the p38 mitogen-activated protein kinase and the p21-activated kinase 1 pathways. ASM cells contain ${\beta}2$-adrenergic receptors and glucocorticoid receptors. They may represent a key target for ${\beta}2$-adrenergic receptor agonist/corticosteroid interactions which have antiproliferative activity against a broad spectrum of mitogens.

• Journal of the Korean housing association
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• v.18 no.4
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• pp.79-88
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• 2007

The purpose of the this study was to provide the basic information about the formation background of urban squatter and their housing state in Korea. This study was progressed on the basis of socio-historical point of view from after the Korean War to the present time. Therefore, this study considered the meaning of housing for urban squatter in the Korean housing history. For this study, the formation background of urban squatter was divided into five periods. The first one was the period of the policy on the mass migration (1955-1960) after the Korean War. The second period was the period of reproduction of deteriorated residential area (1960-1970) for the continuing mass migration policy. The third was the period of disbanding of deteriorated residential area (1970-1980) for redevelopment. The forth period was before the IMF (1980-1997) broke up the deteriorated residential area. The fifth period was after the IMF (1997-) produced the new poverty due to the unemployment and the business failure. Thus, such social change increased the number of urban squatter and created the new type urban poor.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.4
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• pp.465-479
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• 2023

To ensure the safety of disposal facilities for radioactive waste, it is essential to quantitatively evaluate the performance of the waste disposal facilities by using safety assessment models. This paper addresses the development of the safety assessment model for the underground silo of Wolseong Low-and Immediate-Level Waste (LILW) disposal facility in Korea. As the simulated result, the nuclides diffused from the waste were kept inside the silo without the leakage of those while the integrity of the concrete is maintained. After the degradation of concrete, radionuclides migrate in the same direction as the groundwater flow by mainly advection mechanism. The release of radionuclides has a positive linear relationship with a half-life in the range of medium half-life. Additionally, the solidified waste form delays and reduces the migration of radionuclides through the interaction between the nuclides and the solidified medium. Herein, the phenomenon of this delay was implemented with the mass transfer coefficient of the flux node at numerical modeling. The solidification effects, which are delaying and reducing the leakage of nuclides, were maintained the integrity of the nuclides. This effect was decreased by increasing the half-life and the mass transfer coefficient of radionuclides.

• Advances in nano research
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• v.6 no.3
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• pp.243-255
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• 2018

Polystyrene granules were combined with nanosilver to form a nanocomposite film. One-side migration was conducted to test into three food simulants (3% acetic acid, 10% ethanol and 95% ethanol) at $40^{\circ}C$ temperature on different period of time (2, 4, 6, 8 and 10 days). It was found that, among the simulants, the highest migration amount was obtained with 3% acetic acid, while the 95% ethanol revealed the least migration level. Diffusion coefficients of nanosilver particles into simulants were estimated by inverse simulation using experimental data of concentration variation in the simulants. The finite element method used to solve the mass transfer equation and the numerical results indicates the sameresponse with the experimental data. The numerical results confirmed that the highest diffusion coefficient for acetic acid 3% (1.82E-10 to $1.76E-9m^2\;s^{-1}$) and the lowest diffusion coefficient for ethanol 95% from 2 to 10 days were obtained, respectively. Also, results of diffusion coefficient - concentration relation showed, the diffusion coefficient had in direct correlation with time and concentration. The results indicated that, in the 3% acetic acid, due to the increasing of diffusion coefficient of silver nanoparticles, they are released faster and distributed uniformly.

• Journal of the Korean Geosynthetics Society
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• v.5 no.4
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• pp.49-58
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• 2006

Recently, geosynthetic clay liners (GCLs) have increasingly been used to replace compacted clay liners (CCLs) in composite liner systems. Since the introduction of GCLs to waste containment facilities, one of the major concerns about their use has been the hydraulic equivalency to CCLs as required by regulations. Laboratory test results and more recently field observations show that the thickness, or mass per unit area, of hydrated bentonite in a GCL can decrease under normal stress, especially around zones of stress concentration or nonuniform stresses, such as a rock or roughness in the subgrade, a leachate sump, or wrinkles in an overlying geomembrane. This paper presents field case histories that confirm the laboratory observations of bentonite migration and the effect of bentonite migration on hydraulic equivalency and contaminant transport through a GCL.

• Mass Spectrometry Letters
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• v.6 no.2
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• pp.31-37
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• 2015

Phosphorylation upon protein is well known to a key regulator that implicates in modulating many cellular processes like growth, migration, and differentiation. Up to date, grafting of multidimensional separation techniques onto advanced mass spectrometry (MS) has emerged as a promising tool for figuring out the biological functions of phosphorylation in a cell. However, advanced MS-based phosphoproteomics is still challenging, due to its intrinsic issues, i.e., low stoichiometry, less susceptibility in positive ion mode, and low abundance in biological sample. To overcome these bottlenecks, diverse techniques (e.g., SCX, HILIC, ERLIC, IMAC, TiO₂, etc.) are continuously developed for on-/off-line enrichment of phosphorylated protein (or peptide) from biological samples, thereby helping qualitative/quantitative determination of phosphorylated protein and its phosphorylated sites. In this review, we introduce to the overall views of enrichment tools that are universally used to selectively isolate targeted phosphorylated protein (or peptide) from ordinary ones before MS-based phospoproteomic analysis.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.183-191
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• 2008

To determine the age structure of a Hynobius leechii breeding population and analyze relationships between the order of entrance to breeding ponds and physical parameters and age, we studied a wild population of the species in the Research Forests of Kangwon National University in Chuncheon, Kangwon, South Korea from March 16 to April 13, 2005. The age of breeding males ranged one to nine years old and that of females ranged from three to nine years old. The asymptotic sizes of males and females were 6.36 and 6.51 cm, respectively, and the growth coefficients of males and females were 0.71 and 0.81, respectively. The snout-vent length (SVL), head length, and body mass of males were all positively correlated with their age, but female age did not show a significant relationship with any physical parameter. The tail depth, body mass, and condition factors (SVL/body mass $\times$ 100) of both males and females were negatively related with the order of entrance to the breeding pond. The head width and SVL of males were also negatively correlated with the order of entrance, but the SVL of females was positively related with the order of entrance. These results suggest that physical parameters are more important determinants of breeding migration patterns than age. We discuss which of two hypotheses, the mate opportunity hypothesis and the susceptibility hypothesis, is better able to explain the order of entrance to breeding ponds for male and female H. leechii.

• The Korean Journal of Malacology
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• v.32 no.4
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• pp.241-247
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• 2016

Macrophage Migration Inhibitory Factor (MIF) are well-defined role as unique cytokine and critical mediator in acute and chronic inflammatory diseases, autoimmune diseases. In this study, we isolated and characterized a full-length of MIF cDNA from the abalone (Haliotis discus hannai). The full-length cDNA of abMIF was of 1264 bp, consisting of a 5'-terminal UTR of 143 bp, an open reading frame of 360 bp and a 3-terminal UTR of 761 bp. The abalone MIF cDNA encodes a 119-amino acid polypeptide with a calculated molecular mass of 13.4 kDa and isoelectric point of 9.07. Multiple alignments and phylogenetic analysis with the deduced abalone MIF protein and showed strong homology with disk abalone (Haliotis discusdiscus). The deduced amino acid sequence of abMIF exhibited homology with other reported MIFs, such as 80%, with that of other disk abalone H. discus discus MIF gene. Quantitative real-time PCR (qRT-PCR) analysis indicated that abMIF was highly expression observed in hapatopacreas, intestine, foot, and gonad of normal conditioned abalone. Even though AbMIF mRNA level in hemocytes was low under the normal condition, it was sharply up-regulated and reached the maximum at 6 h post-infection with Vibrio parahaemolyticus, and then decreased at 24 h post-infection. This result indicates that abMIF plays an important role in responding in the innate immune system.