• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.173.2-173
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• 2000

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6341-6345
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• 2013

To clarify the role of stem cells in hepatocarcinogenesis, glypican-3 (GPC-3) and E-cadherin expression was investigated in embryonic cell lineages. Mouse embryonic stem cells (ESCs), hepatic progenitor cells (HPCs) and hepatocyte like cells (HCs), representing 0, 22 and 40 days of differentiation, respectively, were treated in vitro with diethylnitrosamine (DEN) at four doses (0, 1, 5 and 15 mM; G1, G2, G3 and G4, respectively) for 24 h and GPC-3 and E-cadherin expression was examined by relative quantitative real-time PCR and immunocytochemistry. GPC-3 mRNA expression was significantly different for G4 at day 0 (p<0.001) and for G4 at day 22 (p<0.01) compared with the control (G1). E-cadherin mRNA expression was significantly different for G3 and G4 at day 0 (p<0.05 and p<0.001, respectively), for G2 and G4 (p<0.05 and p<0.001, respectively) at day 22 and for G2 and G4 (p<0.01 and p<0.001, respectively) at day 40 compared with G1. Immunofluorescence staining for GPC-3 showed a membranous and/or granular expression in cytoplasm of ESCs and HPCs and granular and/or diffuse expression in cytoplasm of HCs, which were also stained by E-cadherin. DEN treatment increased GPC-3 expression in ESCs, HPCs and HCs, with increase of E-cadherin expression. Taken together, the expression of GPC-3 was altered by DEN treatment. However, its expression pattern was different at the stage of embryo stem cells and its derived hepatic lineage cells. This suggests that GPC-3 expression may be modulated in the progeny of stem cells during their differentiation toward hepatocytes, associated with E-cadherin expression.

• Polymer(Korea)
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• v.25 no.2
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• pp.279-292
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• 2001

Two kinds of (hydroxypropyl)cellulose(HPCs) with different molar substitution (MS) and three types of derivatives based on the HPCs: (acetoxypropyl)celluloses, (ethoxypropyl)celluloses, and (cyanoethoxyprofyl)celluloses were synthesized, and their thermal and mesomorphic properties were investigated. All samples, which exhibit cholesteric reflection colours at room temperature, formed right-handed helicoidal structures whose optical pitches (λ$_{ms}$ ) increase with temperature. However, the isotropization ($T_{i}$) and glass temperatures, the magnitude of λ$_{m}$ of the mesophase at the same temperature, and the temperature dependence of λ$_{m}$ of the investigated derivatives highly depended on MS and the length and structure of the side chain introduced in HPC. The results were discussed in terms of the difference in the polarity and flexibility of the substituents and the distance between the main chains. For all derivatives, Am values approached infinity at temperatures above the $T_{i}$, of the mesophase, and no reversal in the sense of the pitch with temperature was detected.

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.173.1-173
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• 2000

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.95-102
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• 2006

To evaluate bacteriological water quality of groundwater in Yeungnam Province, samples were taken from 123 locations during summer and 117 locations during winter. The medians of heterotrophic plate counts.(HPCs) were 30 CFU/mL for the summer samples and 40 CFU/ml for the winter, and more than 25% showed HPCs higher than 100 CFU/ml. Coliform bacteria were detected from 46% of the summer samples and 30% of the winter. In these coliform-positive samples, the medians of coliform counts were 20 CFU/ml for the summer samples and 4 CFU/ml for the winter. Genera such as Citrobacter, Enterobacter, Escherichia, Klebsielia, Pantoea, Rahnellia, and Serratia were identified from the coliform isolates; among them, 48% were members of the genus Enterobacter. While E. cloacae, E. amnigenus, and K. pneumoniae were the most frequently isolated species, E. coli was isolated only from 1 location. The coliform counts were positively correlated with the HPCs, which also positively correlated with water temperature. The results of present study provide further insight on the extent of groundwater contamination with coliform bacteria.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1114-1119
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• 2004

The biofilms on pipe walls in water distribution systems are of interest since they can lead to chlorine demand, coliform growth, pipe corrosion, and water taste and odor problems. As such, the study described in this paper is part of an AWWARF and Tampa Bay Water tailored collaboration project to determine the effect of blending different source waters on the water quality in various distribution systems. The project was based on 18 independent pilot distribution systems (PDS), each being fed by a different water blend (7 finished waters blended in different proportions). The source waters compared were groundwater, surface water, and brackish water, which were treated in a variety of pilot distribution systems, including reverse osmosis (RO) (desalination), both membrane and chemical softening, and ozonation-biological activated carbon (BAC), resulting in a total of 7 different finished waters. The observations from this study consistently demonstrated that unlined ductile iron was more heavily colonized by a biomass than galvanized steel, lined ductile iron, and PVC (in that order) and that the fixed biomass accumulation was more influenced by the nature of the supporting material than by the water quality (including the secondary residual levels). However, although the bulk liquid water cultivable bacterial counts (i.e. heterotrophic plate counts or HPCs) did not increase with a greater biofilm accumulation, the results also suggested that high HPCs corresponded to a low disinfectant residual more than a high biofilm inventory. Furthermore, temperature was found to affect the biofilms, plus the AOC was important when the residual was between 0.6 and 2.0 mg $Cl_2/l$. An additional aspect of the current study was that the potential of the exoproteolytic activity (PEPA) technique was used along with a traditional so-called destructive technique in which the biofilm was scrapped off the coupon surface, resuspended, and cultivated on an R2A agar. Both techniques indicated similar trends and relative comparisons among the PDSs, yet the culturable biofilm values for the traditional method were several orders of magnitude lower than the PEPA values.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.42-52
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• 2002

Two full-scale distribution systems, one treating water by ozonation and another treating water by nanofiltration in parallel with lime softening, were monitored for bacterial growth. Both systems kept disinfectant residuals surf as chlorine and chloramine in their respective distribution systems. Bacterial growth was assessed by heterotrophic plate counts (HPC) on R2A agar. In the distribution systems fed by ozonated water, HPCs were correlated ($R^2$= 0.97) using an exponential model with the assimilable organic carbon (AOC) at each sampling site. Also, it was observed that ozonation caused a significant increase in the AOC concentration of the distribution system (over 100％ increase) as well as a significant increase in the bacterial counts of the distribution system (average increase over 100％). The HPCs from the distribution systems fed by nanofiltration in parallel with lime-softening water also displayed an exponential correlation ($R^2$ = 0.75) with an exponential model based on AOC. No significant correlation was found between bacteria growth on R2A agar and BDOC concentrations. Therefore, in agreement with previous work, bacterial growth in the distribution systems was found to correlate with AOC concentrations.

• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.412-416
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• 2012

Porous SiC ceramics were prepared by using recycled SiC sludge, which is an industrial waste generated from solar cell industry. Polycarbosilane derivatives, such as polycarbosilane (PCS), polyphenylcarbosilane (PPCS) and hydridopolycarbosilane (HPCS) were used as binding agents for the fabrication of porous SiC ceramics at $1800^{\circ}C$ under Ar atmosphere. The effects of the various binding agents having different C/Si ratios were discussed on the sintering and porosity of the SiC ceramics. The prepared porous SiC ceramics were characterized by X-ray Diffraction (XRD) and Field-Emission Scanning Electron Microscope (FE-SEM). Thermal conductivity and porosity of SiC ceramics were measured at room temperature, and they were 56.7W/mK and 29.8%, respectively.

• Journal of Digital Contents Society
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• v.14 no.4
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• pp.529-536
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• 2013

Lack of proper amount of sun lights and wind strength which are major factors of solar power and wind power system may cause poor electric power generation and decrease the lifetime of batteries that are major energy saving units. Because the PCS, which is essential in solar and wind power system, for small power generation system has been rarely developed an efficient and stable PCS for small power generation system is highly required. In this paper, we design a new constant current/constant voltage type hybrid PCS by which stand alone/grid connected operation with commercial power system is available and implement the designed PCS as a protype for performance verification.

• Computers and Concrete
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• v.2 no.3
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• pp.189-202
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• 2005

This paper presents an analysis of some experimental results concerning micro-structural tests, permeability measurements and strain-stress tests of four types of High-Performance Concrete, exposed to elevated temperatures (up to $700^{\circ}C$). These experimental results, obtained within the "HITECO" research programme are discussed and interpreted in the context of a recently developed mathematical model of hygro-thermal behaviour and degradation of concrete at high temperature, which is briefly presented in the Part 2 paper (Gawin, et al. 2005). Correlations between concrete permeability and porosity micro-structure, as well as between damage and cracks' volume, are found. An approximate decomposition of the thermally induced material damage into two parts, a chemical one related to cement dehydration process, and a thermal one due to micro-cracks' development caused by thermal strains at micro- and meso-scale, is performed. Constitutive relationships describing influence of temperature and material damage upon its intrinsic permeability at high temperature for 4 types of HPC are deduced. In the Part II of this paper (Gawin, et al. 2005) effect of two different damage-permeability coupling formulations on the results of computer simulations concerning hygro-thermo-mechanical performance of concrete wall during standard fire, is numerically analysed.