• Journal of Conservation Science
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• v.25 no.1
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• pp.101-114
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• 2009

Potsherds and kilns of the AD 3th century excavated from Gundong and Majeon sites, Korea were studied to investigate the production techniques and provenance of potsherds and kilns on the pastes. For potsherds, kilns blocks and in-situ paleo-soils, provenance of raw materials were estimated through mineralogy and geochemistry, while production technique and thermal feature of kilns were investigated through observation of textures and compositions as well as firing experiment on paleo-soils. As a result of study, potsherds and kilns were found to have similar mineralogical compositions as the neighboring paleo-soils and to have same evolution path with that of geochemistry. The potsherds were divided into 3 groups according to firing temperature and production technique. Group 1 consists of reddish stamped pattern pottery with loose textures, which has many pores and contains many iron oxides. Its temper is less than about 0.5mm, and was probably fired between 700 to $800^{\circ}C$. Group 2 contains ash to grayish blue stamped pattern pottery, which has vitrified texture and few pores. Its temper is less than about 0.5mm, and was probably fired from 900 to $1,000^{\circ}C$. However, some potsherd belongs to the group 2 in terms of features for temper and pastes, but it was probably fired over $1,100^{\circ}C$. Group 3 contains reddish and grayish stamped pattern pottery. It has vitrified matrix, few pores and temper consists of polycrystalline quartz and feldspar over 2mm, and it was probably fired around $1,000^{\circ}C$. The kiln had experienced temperature from 600 to $700^{\circ}C$ on the wall, from 900 to $1,000^{\circ}C$ on the bottom, suggesting the function of high temperature firing.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.871-888
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• 1997

Background : It is now thought that the earliest manifestation of idiopathic pulmonary fibrosis is alveolitis, that is, an accumulation of inflammatory and immune effector cells within alveolar walls and spaces. Inflammatory cells including alveolar macrophages and resident normal pulmonary tissue cells participate through the release of many variable mediators such as inflammatory growth factors and cytokines, which contribute to tissue damage and finally cause chronic pulmonary inflammation and fibrosis. This study was performed to investigate the source and distribution pattern of transforming growth factor-${\beta}_1$(TGF-${\beta}_1$), platelet derived growth factor(PDGF), basic fibroblast growth factor(bFGF), interleukin 1(IL-1), interleukin 6(IL-6), tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and the role of these mediators on bleomycin(BLM)-induced pulmonary injury and fibrosis in rats. Method : Wistar rats were divided into three groups(control group, BLM treated group, BLM and vitamine E treated group). Animals were sacrificed periodically at 1, 2, 3, 4, 5, 7, 14, 21, 28 days after saline or BLM administration. The effects were compared to the results of bronchoalveolar lavage fluid analysis, light microscopic findings, immunohistochemical stains for six different mediators(TGF-${\beta}_1$, PDGF, bFGF, IL-1, IL-6 and TNF-$\alpha$) and mRNA in situ hybridization for TGF-${\beta}_1$. Results : IL-1 and IL-6 are maximally expressed at postbleomycin 1~7th day which are mainly produced by neutrophils and bronchiolar epithelium. It is thought that they induce recruitment of inflammatory cells at the injury site. The expression of IL-1 and IL-6 at the bronchiolar epithelium within 7th day is an indirect evidence of contribution of bronchiolar epithelial cells to promote and maintain the inflammatory and immune responses adjacent to the airways. TNF-$\alpha$ is mainly produced by neutrophils and bronchiolar epithelial cells during 1~5th day, alveolar macrophages during 7~28th day. At the earlier period, TNF-$\alpha$ causes recruitment of inflammatory cells at the injury site and later stimulates pulmonary fibrosis. The main secreting cells of TGF-${\beta}_1$ are alveolar macrophages and bronchiolar epithelium and the target is pulmonary fibroblasts and extracellular matrix. TGF-${\beta}_1$ and PDGF stimulate proliferation of pulmonary fibroblasts and TGF-${\beta}_1$ and bFGF incite the fibroblasts to produce extracellular matrix. The vitamine E and BLM treated group shows few positive cells(p<0.05). Conclusion : After endothelial and epithelial injury, the neutrophils and bronchiolar epithelium secrete IL-1, IL-6, TNF-$\alpha$ which induce infiltration of many neutrophils. It is thought that variable enzymes and $O_2$ radicals released by these neutrophils cause destruction of normal lung architecture and progression of pulmonary fibrosis. At the 7~28th day, TGF-${\beta}_1$, PDGF, bFGF, TNF-$\alpha$ secreted by alveolar macrophages sting pulmonary fibroblasts into proliferating with increased production of extracellular matrix and finally, they make progression of pulmonary fibrosis. TNF-$\alpha$ compares quite important with TGF-${\beta}_1$ to cause pulmonary fibrosis. Vitamine E seems to decrease the extent of BLM induced pulmonary fibrosis.

• Journal of the Korea Concrete Institute
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• v.21 no.3
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• pp.327-335
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• 2009

In the seismic region, non-ductile structures often form soft story and exhibit brittle collapse. However, structure demolition and new structure construction strategies have serious problems, as construction waste, environmental pollution and popular complain. And these methods can be uneconomical. Therefore, to satisfy seismic performance, so many seismic retrofit methods have been investigated. There are some retrofit methods as infill walls, steel brace, continuous walls, buttress, wing walls, jacketing of column or beam. Among them, the infilled frames exhibit complex behavior as follows: flexible frames experiment large deflection and rotations at the joints, and infilled shear walls fail mainly in shear at relatively small displacements. Therefore, the combined action of the composite system differs significantly from that of the frame or wall alone. Purpose of research is evaluation on the seismic performance of infill walls, and improvement concept of this paper is use of SHCCs (strain-hardening cementitious composites) to absorb damage energy effectively. The experimental investigation consisted of cyclic loading tests on 1/3-scale models of infill walls. The experimental results, as expected, show that the multiple crack pattern, strength, and energy dissipation capacity are superior for SHCC infill wall due to bridging of fibers and stress redistribution in cement matrix.

• Journal of Periodontal and Implant Science
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• v.30 no.3
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• pp.491-504
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• 2000

In clinical therapy, the current goal of dental implants is to enhance quantity and quality of osseointegration. Surface roughness and oxide structure are considered to influence the behavior of adherent cells. The purpose of this study is to evaluate the effect of different surface treatment on cellular response. The attachment and proliferation of osteoblast-like cell on sandblasted, sandblasted and etched, thermal oxidated surfaces have been compared. Sandblasting was done with $Al_2O_3$ particles(grain size of $50{\mu}m$), etching was processed with $NH_4OH$ : $H_2O_2$ : $H_2O(1:1:5)$ at $90^{\circ}C$ for 1 minute. Thermal oxidation was followed sandblasting and etching at $400^{\circ}C$, $600^{\circ}C$, $800^{\circ}C$ for 2 hours. Measurement of surface roughness after the different treatment did not show any differences of Ra value between terated surfaces. Cell attachment and proliferation were increased during experiment period, but no difference was observed. SEM evaluation revealed a similar pattern of osteoblast-like cells, well attached with dendritic extension and producing numerous matrix vesicles on cell surface. The results of this study showed that oxide layer alteration by thermal oxidation did not affect the attachment and proliferation of osteoblast-like cells. This suggests the possibility that the cellular responses are further influenced by surface roughness than titaniun oxide structure.

• Analytical Science and Technology
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• v.9 no.3
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• pp.270-278
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• 1996

Response mechanism for the chloride-selective membrane doped with 5, 10, 15, 20-tetraphenyl(porphyrinato)manganase(III) chloride(Mn(TPP)Cl) in PVC/DOS matrix is proposed by examining the visible spectra of the corresponding optode membrane. The visible spectra of Mn(TPP)Cl-doped membrane placed in aqueous solution show that the chloride ligand is easily replaced with water molecule. When other halogen ions, such as $F^-$, $Br^-$ and $I^-$, are added to the sample solution, they replace the water ligand, exhibiting distinctive change in the Soret band of Mn(TPP). On the other hand, bulky anions, such as SCN and salicylate, do not form a bond with the central metal. These results suggests that the potentiometric response of Mn(TPP)-based membrane results either from the ligand exchange (water with halides) at the central metal or from the counter ion exchange (chlorides with bulky lipophilic anions) around the positively charged porphyrin molecule in membrane phase. It was also noted that both hydration enthalpies of anions and their binding constants to Mn(TPP) play critical role in determining the potentiometric selectivity pattern of the membrane.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.5
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• pp.265-276
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• 2017

Heavy metals leaching from closed mines have been causing severe environmental problems in nearby soil ecosystems. Mine reclamation in Korea has been recently implemented based on the heavy metal immobilization (a.k.a., stabilization). Since the immobilization temporarily fixes the heavy metals to the soil matrix, the potential risk of heavy metal leaching still exists. Therefore the appropriate monitoring and the related policies are required to safeguard the soils, where all the cultivations occur. The current monitoring methods are based on either heavy metal concentration or simple toxicity test. Those methods, however, are fragmented and hence it is difficult to evaluate the site in an integrated manner. In this study, as the integrated approach, ecological functional state evaluation with a multivariate statistical tool was employed targeting physiochemical soil properties, heavy metal concentrations, microbial enzymatic activity, and arsenic respiratory reductase gene quantity. Total 60 soil samples obtained from three mines (Pungjeong, Jeomdong, Seosung) were analyzed. As a result, the stabilized layer soil and lower layer soil have shown the similar pattern in Pungjeong mine. In contrast, Jeomdong and Seosung mine have shown the similarity between the stabilized layer soil and the cover layer soil, indicating the possible contamination of the cover layer soil.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.4
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• pp.413-423
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• 2013

To elucidate the variation of species composition, biomass and length distribution of flatfishes by the period and region in the Uljin marine ranching area, bottom trawl survey was investigated at the six stations from Feb. 2008 to Dec. 2010. During the survey period, a total 4 families 17 species in the Pleuronectiformes, average 69,158 $ind./km^2$ and 5,625 $kg/km^2$ were identified, in 2008 appeared in 14 species, average 25,798 $ind./km^2$ and 2,333 $kg/km^2$ and in 2009 appeared in 13 species, average 102,360 $ind./km^2$ and 5,634 $kg/km^2$ and in 2010 appeared in 14 species, average 75,704 $ind./km^2$ and 8,632 $kg/km^2$. The individual dominant species, occupying over 10% of total individuals, was Pleuronectes herzensteini (20,811 ind., 30.0%), Hippoglossoides pinetorum (18,666 ind., 26.9%) and Glyptocephalus stelleri (13,499 ind., 19.4%) also the biomass dominant species, occuping over 10% of total biomass, was P. herzensteini (2,207 kg, 39.3%), Pleuronectes yokohamae (857 kg, 15.3%), H. pinetorum (761 kg, 13.5%), Kareius bicoloratus (677 kg, 12.1%). From the cluster and MDS analysis based on Bray-Curtis similarity matrix of fourth root transformed data of species number and individuals in the Uljin marine ranching area from Feb. 2008 to Dec. 2010 was divided into two different groups of the flatfishes community in 2008 and from Jan. to Apr. in 2009 and 2010 (Group A) and the pleuronectiform community in from May to Dec. in 2009 and 2010 (Group B). From the cluster and MDS analysis using the similarity of demersal organisms community among six stations, the Uljin marine ranching area was divided into two different groups of Group 1 (St. 1 and St. 3) and Group 2 (St. 2, St. 4, St. 5 and St. 6).

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.3
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• pp.307-326
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• 2004

Statement of problem. The long-term success of implants is the development of a stable direct connection between bone and implant surface, which must be structural and functional. To improve a direct implant fixation to the bone, various strategies have been developed focusing on the surface of materials. Among them, altering the surface properties can modify cellular responses such as cell adhesion, cell motility and bone deposition. Purpose. This study was to evaluate the cellular behaviors on the surface-modified titanium by morphological observation, cellular proliferation and differentiation. Material and methods. Specimens were divided into five groups, depending on their surface treatment: electropolishing(EP) anoclizing(AN), machining(MA), blasting with hydroxyapatite particle(RBM) and electrical discharge machining(EDM). Physicochemical properties and microstructures of the specimens were examined and the responses of osteoblast-like cells were investigated. The microtopography of specimens was observed by scanning electron microscopy(SEM). Surface roughness was measured by a three-dimensional roughness measuring system. The microstructure was analyzed by X-ray diffractometer(XRD) and scanning auger electron microscopy(AES). To evaluate cellular responses to modified titanium surfaces, osteoblasts isolated from neonatal rat were cultured. The cellular morphology and total protein amounts of osteoblast-like cell were taken as the marker for cellular proliferation, while the expression of alkaline phosphatase was used as the early differentiation marker for osteoblast. In addition, the type I collagen production was determined to be a reliable indicator of bone matrix synthesis. Results. 1. Each prepared specimen showed specific microtopography at SEM examination. The RBM group had a rough and irregular pattern with reticulated appearance. The EDM-treated surface had evident cracks and was heterogeneous consisting of broad sheet or plate with smooth edges and clusters of small grains, deep pores or craters. 2. Surface roughness values were, from the lowest to the highest, electropolished group, anodized group, machined group, RBM group and EDM group. 3. All groups showed amorphous structures. Especially anodized group was found to have increased surface oxide thickness and EDM group had titaniumcarbide(TiC) structure. 4. Cells on electropolished, anodized and machined surfaces developed flattened cell shape and cells on RBM appeared spherical and EDM showed both. After 14 days, the cells cultured from all groups were formed to be confluent and exhibited multilayer proliferation, often overlapped or stratified. 5. Total protein amounts were formed to be quite similar among all the group at 48 hours. At 14 days, the electropolished group and the anodized group induced more total protein amount than the RBM group(P<.05). 6. There was no significant difference among five groups for alkaline phosphatase(ALP) activity at 48 hours. The AN group showed significantly higher ALP activity than any other groups at 14 days(P<.05). 7. All the groups showed similar collagen synthesis except the EDM group. The amount of collagen on the electropolished and anodized surfaces were higher than that on the EDM surface(P<.05).

• Journal of the Microelectronics and Packaging Society
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• v.16 no.4
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• pp.29-32
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• 2009

Dense and periodic arrays of nano-sized holes were patterned in oxide thin film on GaAs substrate. To obtain the nano-size patterns, self-assembling diblock copolymer was used to produce thin film of uniformly distributed parallel cylinders of polymethylmethacrylate (PMMA) in polystyrene (PS) matrix. The PMMA cylinders were removed with UV expose and acetic acid rinse to produce PS nanotemplate. By reactive ion etching, pattern of the PS template was transferred to under laid silicon oxide layer. Transferred patterns were reached to the GaAs substrate by controlling the dry etching time. We confirmed the achievement of etching through the removing oxide layer and observation of GaAs substrate surface. Optimized etching time was 90 to 100 sec. Pore sizes of the nanopattern in the silicon oxide layer were 20~22 nm.

• Journal of the Korean earth science society
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• v.24 no.5
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• pp.477-490
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• 2003

Bottom sediments from Youngil Bay, East Coast of Korea, were analyzed for grain composition as well as elemental compositions and total organic carbon (TOC) content in order to investigate the spatial variability and content of metal elements. Grain size distribution of the sediments seems to be controlled by anticlockwise current pattern with bottom topography of the study area. Spatial variability of TOC and all elemental contents reflects those of grain size, but an exception was found in the harbor area (Old-Port): their contents are high in the central part of the bay with the muddy sediment and decrease toward the sand-dominated coastal zone. However, contents of Ca, Sr, K are high in the sand-dominated coastal zone and contents of some heavy metals (Cd, Cu, Zn) are high in the Old-Port area and the mouth of Hyeongsan River. The correlation matrix and R-mode factor analyses reveal that four important factors controlling the distribution of metals in the bay are sediment grain size (or quartz dilution effect), the formation of sulfide minerals associated with decomposition of organic matters under anoxic geochemical environment, calcium carbonate (mainly shell fragments) and coarse-grained feldspar mineral. According to the metal content of labile fraction an CER (concentration enrichment ratio) value, high accumulation of some heavy metals in the harbor area seems to result not formed by early diagenetic processes under anoxic environment.