• Fire Science and Engineering
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• v.25 no.6
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• pp.83-88
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• 2011

This study presented the structure and characteristics of vinyl cords used for wiring electric equipment and appliances and analyzed the photographs of damaged flat-type vinyl cords (VFF, $1.25mm^2$) and the metallic cross-sectional structure of melted conductors. Normal VFFs were made by twisting several strands together and the surface of the conductor was red brown. In addition, from the analysis of the metallic structure of the conductor, it was found that its grains had been elongated. The surface of a VFF damaged by normal flame showed no sheen with carbonized insulation material fused on the conductor surface. In addition, from the analysis of the cross-sectional structure of the melted area, it was found that voids of a certain shape were formed on it but that the cord's own elongation structure could not be checked. The cross-sectional analysis of the melted conductor damaged by the external flame applied to a VFF to which electric current was being applied showed no elongation structure for each cord, and revealed that irregular voids and a columnar structure had grown. The surface of the VFF damaged by overcurrent was uniformly carbonized and the cross-sectional structure analysis of the melted conductor revealed that the dendritic structure had grown. The analysis of the characteristics of the VFF melted by short-circuit showed that even though some part of the surface was contaminated, it showed little sheen and that the area rebounded by melting was round in shape. In addition, the cross-sectional structure analysis using a metallurgical microscope showed the boundary surface and columnar structure and revealed an amorphous structure like normal copper at areas other than the melted conductor.

• Journal of Conservation Science
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• v.32 no.4
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• pp.549-560
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• 2016

The purpose of this study is to identify the material characteristics of blackwares excavated from the Bonggok kiln site in Jinan-gun, Jeollabuk-do Province, South Korea, by scientific analyses and a reproduction experiment. Scientific analyses were conducted to determine the physical properties, chemical composition and for microscopic observation of blackwares. A reproduction experiment was also conducted by producing ceramic samples with black glaze, red ocher and limestone, and then cross sections of the samples were observed. The analysis results showed that all the excavated blackwares have similar properties such as chromaticity, specific gravity, absorption factor and porosity, but there is a difference depending on the crystallization of the ceramics. Thermal analysis showed that the exothermic peak was observed at about $1200^{\circ}C$, and crystal structure analysis indicated the presence of mullite. Hence, it can be concluded that the firing temperature of the excavated blackwares was around $1100-1200^{\circ}C$. Moreover, the glaze present on these blackwares has about 22% higher $Fe_2O_3$ content than those excavated from other places; however, the former has lower CaO content. For the reproduction experiment, samples were made using limestone as a flux and red ocher as a glaze. The results show that the cross section of the glaze layer of the reproduced sample have iron crystals with dendritic structures, similar to those present in the excavated black-wares. It is assumed that such iron crystals were formed during the process of melting and solidification of the iron oxide present in the blackwares.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.86-92
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• 2006

Background: Germanium compounds are increased to use in nutrient foods and medicines in terms of antibiotics to microbes, anticancer, modulation of immune system and neutralizing heavy metal toxins. Geranti Bio-Ge Yeast, containing stable organic germanium and bound to the yeast protein was developed by Geranti Pharm. LTD. and the modulation effect in the immune system was examined in vivo and in vitro. Methods: The compound, Geranti Bio-Ge Yeast, was fed to female Balb/c mice (each group has 10 mice) for 4 weeks and the yeast powder and steamed red ginseng powder were used as control during the same feeding time points. During 4 weeks there was no symptom to be considered, and after 4 weeks feeding all mice were sacrificed to check the changes of related immune cells and subsidiary responses (i.e. cell counting, FACS, MTT, LDH, PFC assay). Results: In pre-post comparison, B cell population was increased in the group of Geranti Bio-Ge Yeast in a dose dependent manner (100 to 800 mg/kg). However, the population of T cell, dendritic cell and macrophage was not comparably changed in all doses. The ability of cytokine production and proliferation was almost same level as shown in control group. In contrast, PFC assay informed that the compound increase the antibody production ability when fed over 200 mg/kg implying that the increase of PFC number might be due to the increase of B cells. Conclusion: Over the entire study, we concluded that the compound, Geranti Bio-Ge Yeast has better potential in immune response in terms of B cell proliferation than that of positive control, red ginseng, and the compound can be one of the future candidates for a new supplementary source improving immune system activity.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.607-612
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• 2005

Heat shock protein 70 (HSP70) is a multigene family composed of constitutively expressed members(Hsc70) and stress-inducible members (Hsp70). In the mammalian nervous system, a considerable amount of HSPs is also synthesized under normal conditions suggesting that they play an important role in the metabolism of unstressed cells. In this study we examined the expression of Hsp70 in the synapses of rat cerebellar neurons. Immunohistochemistry using specific antibodies revealed that both Hsp70 and Hsc70 are expressed in the cerebellar tissue, with strongest expression in Purkinje cells followed by granule cells. Neurons in deep cerebellar nuclei were also intensely stained by Hsp70 antibody. Immunocytochemical stainings of cultured cerebellar cells showed that Hsp70 is expressed in both Purkinje and granule cells. The expression was punctate in the soma and along dendritic trees, and the punctae were colocalized with those of PSD95, a postsynaptic marker. Immunoblotting also indicates that Hsp70 is associated with the postsynaptic density fraction. Taken together, our results indicate that the Hsp70 is expressed in cerebellar neurons in normal conditions, and that some are localized in the synapses.

• Korean Journal of Materials Research
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• v.11 no.6
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• pp.502-507
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• 2001

The effect of solidification rate on the microstructure of directionally solidified IN792+ Hf superalloy has been studied. Solidification sequence and precipitation behavior of the alloy have been analysed by microstructural observation. The script carbide transformed to faceted carbide with decreasing solidification rates. The incorporation of ${\gamma}$ phase into the faceted carbide was due to dendritic growth of carbides. Some elongated carbide bars formed along the grain boundaries at a solidification rate of 0.5$\mu\textrm{m}$/s. Two zones, ${\gamma}$' forming elements enriched zone and depleted zone, were found in the residual liquid area. Eutectic ${\gamma}$/${\gamma}$' nucleated in the f forming elements enriched zone. Formation of eutectic ${\gamma}$/${\gamma}$' increased the ratio of (Ti+Hf+Ta+W)/Al and induced η phase precipitation. The ratio of (Ti+Hf+Ta+W)/Al decreased at lower solidification rates due to sufficient back diffusion in the residual liquid area. Hence, the Precipitation of the η Phase efficiently suppressed at the lower solidification rate.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.2
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• pp.125-131
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• 2009

An electrolytic system (zinc anode-gallium cathode) was setup to evaluate the performance of several stirrers prepared for this study, where stirrers have been used to prevent uranium from forming dendrite on the cathode in pyrochemical process. In the case of no-stirring condition, zinc dendrites began to grow on the gallium surface in 1 hour and some dendrite grew out of the cathode crucible around 6 hours. When a rectangular stirrer or a tilt stirrer was rotated, at 40${\sim}$150 rpm, to mix the liquid gallium cathode, dendritic growth of zinc metal was prevented irrespective of revolution speed, but some of the deposits overflowed out of the cathode crucible owing to the large centrifugal forces at 150 rpm. The harrow stirrer did not nearly retard the dendrite growth at 40 rpm, but the dendrite growth was retarded at higher than 100 rpm and the zinc deposits also did not overflow at 150 rpm. Pounder could also prevent the dendrite growth to some extent but it had some difficulties in operation compared with other types of stirrers.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.3
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• pp.199-206
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• 2013

Electrowinning process in pyroprocessing recovers U (uranium) and TRU (Trans Uranium) elements simultaneously from spent fuels using a liquid cadmium cathode (LCC). When the solubility limit of U deposits over 2.35wt% in Cd, U dendrites were formed on the LCC surface during the electrodeposition at $500^{\circ}C$. Due to the high surface area of dendritic U, the deposits were not submerged into the liquid cadmium pool but grow out of the LCC crucible. Since the U dendrites act as a solid cathode, it prevents the co-deposition of U and TRUs. In this study, the electrodeposition of U onto a LCC was carried out at 440 and $500^{\circ}C$ to compare the morphology and component of U deposits. The U deposits at $440^{\circ}C$ have a specific shape and were stacked regularly at the center of the LCC pool, while the U dendrites (i.e., ${\alpha}$-phase) at $500^{\circ}C$ were grow out of the LCC crucible. Through the microscopic observation and XRD analysis, the electrodeposits at $440^{\circ}C$, which have a round shape, were identified as an intermetallic compound such as $UCd_{11}$. It can be concluded that the LCC electrowinning operation at $440^{\circ}C$ achieves the co-recovery of U and TRU without the formation of U dendrites.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.305-311
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• 2007

Glucocorticoids (GCs) alter metabolism, synaptogenesis, apoptosis, neurogenesis, and dendritic morphology in the hippocampus. To better understand how glucocorticoids regulate these aspects of hippocampal biology, we studied gene expression patterns in the CA3 (Hippocampal pyramidal cell field CA3) and dentate gyrus (DG). Litter-matched Lewis inbred rats treated for 20 days with either 9.5 mg per day sustained-release corticosterone or placebo pellets were compared with high-density oligonucleotide microarray analysis (Rat Neurobiology U34 Arrays, Affymetrix). In placebo-treated rats, 32 genes were expressed at greater levels in CA3 than DG, whereas 3 genes were expressed at great levels in DC than CA3. Regional differences were also apparent in corticosterone-induced changes in the hippocampal transcriptome. Six genes in CA3 and 41 genes in DC were differentially regulated by corticosterone. As per the glucocorticoid effects on gene transcription in the brain, forty three of these genes were upregulated, and 4 genes were downregulated. Genes differentially expressed in hippocampus included those for 13 neurotransmitter proteins, 5 ion channel related proteins, 4 transcription factors, 3 neurotrophic factors, 1 cytokine, 1 apoptosis related protein, and 5 genes involved in synaptogenesis. Interestingly, GCs can have suppressive effects on brain BDNF mRNA transcription, one of the neurotrophic factors. These results indicate the diversity of targets affected by chronic exposure to corticosterone and highlight important regional differences in hippocampal neurobiology.

• Journal of Life Science
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• v.17 no.12
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• pp.1627-1633
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• 2007

c-Jun N-terminal kinase (JNK)-interacting protein 1 (JIP1), also known as Islet-brain 1 (IB1), is a scaffold protein that is highly expressed in neurons and pancreatic ${\beta}-cells$. In this study subcellular localization of JIP was investigated in cultured rat hippocampal neurons using an antibody that recognize all variants of JIP1, JIP-2 and JIP-3. The overall expression profile of JIP is punctate throughout soma and dendrites. Statistic analysis showed that $54.8{\pm}4.0%\;and\;94.1{\pm}4.5%$ of total JIP immunopuncta overlapped with those of excitatory postsynaptic markers SD-95 and ${\alpha}Camik$, respectively. In contrast, only $8.6{\pm}0.5%\;and\;7.3{\pm}0.5%$ of JIP clusters overlapped with those of inhibitory postsynaptic markers glycine receptor (GlyR) and gephyrin, respectively. JIP clusters overlapped or juxtaposed with SV2 but not GAD, markers for general and inhibitory nerve terminals, respectively. A substantial fraction $(29.3{\pm}1.0%)$ of flotillin immunopuncta, a marker for lipid rafts, clusters overlapped with those of JIP. In addition, JIP was highly expressed in some select ends of dendrites but minimal in axons. These data suggest important roles of JIP in excitatory postsynaptic sites, lipid rafts and dendritic ends.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.851-856
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• 2005

Although valuable microbes have been isolated from the soil for the various productions of useful components, the microbes which can be cultivated in the laboratory are only $0.1-1\%$ of all microbes. To solve this problem, the study has recently been tried for making the valuable components from the environment by directly separating unculturable micrbial DNA in the soil. But it is known that humic acid originated from the soil interrupts various restriction enzymes and molecular biological process. Thus, in order to prevent these problems, this study modified the method separated soil DNA with phenol, CTAB and PEG. In order to compare the degree of purity for each DNA and the molecular biological application process, $A_{260}/A_{280}$ ratio, restriction enzymes, and PCR were performed. In case of DNA by the modified method, total yield of DNA was lower but $A_{260}/A_{280}$ ratio was higher than the previously reported methods. It was confirmed that the degree of purity is improved by the modified method. But it was not cut off by all kinds of tested restriction enzymes because of the operation of a very small amount of interrupting substances. When PCR was operated with each diluted DNA in different concentrations and GAPDH primer, the DNA by the modified method could be processed for PCR in the concentration of 100 times higher than by the previously reported separation method. Therefore, this experiment can find out the possibility of utilization for the unknown substances by effectively removing the harmful materials including humic acid and help establishing metagenomic DNA library from the soil DNA having the high degree of purity.