• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.180-186
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• 2013

The primary goal of attack on steganographic images, termed steganalysis, is to detect the presence of hidden data by finding statistical abnormality of a stego-media caused by data embedding. This paper proposes a novel steganographic scheme based on improving the (7, 4) Hamming code for digital images. The proposed scheme embeds a segment of six secret bits into a group of nine cover pixels at a time. The experimental results show that the proposed scheme achieves a 0.67bpp embedding payload and a slightly higher visual quality of stego images compared with the previous arts.

• Journal of Marine Bioscience and Biotechnology
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• v.5 no.4
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• pp.1-7
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• 2011

Bone health is maintained by balance between bone resorption and bone formation, and bone homeostasis requires balanced interactions between osteoblasts and osteoclasts. Most of drugs and functional foods for bone health have been developed as bone resorption inhibitors, which maintain bone mass by inhibiting the function of osteoclasts. The recent studies have shown beneficial effects of marine natural products on bone health. Therefore, this review is aimed to study effects of marine-derived natural substances on osteoarthritis inhibition via attenuation of MMPs and osteoblastic differentiation via activation of alkaline phosphatase (ALP), osteoclacin (OC), bone morphogenic protein-2 (BMP-2) as an important factor for bone formation, and mineralization. The present review can provide new insights in the osteoblastic differentiation of marine natural products and possibility for their application in bone health supplement.

• Molecules and Cells
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• v.37 no.4
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• pp.330-336
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• 2014

Thymosin beta4 (TB4) has multiple functions in cellular response in processes as diverse as embryonic organ development and the pathogeneses of disease, especially those associated with cardiac coronary vessels. However, the specific roles played by TB4 during heart valve development in vertebrates are largely unknown. Here, we identified a novel function of TB4 in endothelial-mesenchymal transformation (EMT) in cardiac valve endocardial cushions in zebrafish. The expressions of thymosin family members in developing zebrafish embryos were determined by whole mount in situ hybridization. Of the thymosin family members only zTB4 was expressed in the developing heart region. Cardiac valve development at 48 h post fertilization was defected in zebrafish TB4 (zTB4) morpholino-injected embryos (morphants). In zTB4 morphants, abnormal linear heart tube development was observed. The expressions of bone morphogenetic protein (BMP) 4, notch1b, and hyaluronic acid synthase (HAS) 2 genes were also markedly reduced in atrio-ventricular canal (AVC). Endocardial cells in the AVC region were stained with anti-Zn5 antibody reactive against Dm-grasp (an EMT marker) to observe EMT in developing cardiac valves in zTB4 morphants. EMT marker expression in valve endothelial cells was confirmed after transfection with TB4 siRNA in the presence of transforming growth factor ${\beta}$ ($TGF{\beta}$) by RT-PCR and immunofluorescent assay. Zn5-positive endocardial AVC cells were not observed in zTB4 morphants, and knockdown of TB4 suppressed TGF-${\beta}$-induced EMT in ovine valve endothelial cells. Taken together, our results demonstrate that TB4 plays a pivotal role in cardiac valve formation by increasing EMT.

• Journal of Korean Society of Disaster and Security
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• v.16 no.4
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• pp.45-59
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• 2023

The global focus on mitigating climate change has traditionally centered on carbon dioxide, but recent attention has shifted towards methane as a crucial factor in climate change adaptation. Natural settings, particularly aquatic environments such as wetlands, reservoirs, and lakes, play a significant role as sources of greenhouse gases. The accumulation of organic contaminants on the lake and reservoir beds can lead to the microbial decomposition of sedimentary material, generating greenhouse gases, notably methane, under anaerobic conditions. The escalation of methane emissions in freshwater is attributed to the growing impact of non-point sources, alterations in water bodies for diverse purposes, and the introduction of structures such as river crossings that disrupt natural flow patterns. Furthermore, the effects of climate change, including rising water temperatures and ensuing hydrological and water quality challenges, contribute to an acceleration in methane emissions into the atmosphere. Methane emissions occur through various pathways, with ebullition fluxes-where methane bubbles are formed and released from bed sediments-recognized as a major mechanism. This study employs Biochemical Methane Potential (BMP) tests to analyze and quantify the factors influencing methane gas emissions. Methane production rates are measured under diverse conditions, including temperature, substrate type (glucose), shear velocity, and sediment properties. Additionally, numerical simulations are conducted to analyze the relationship between fluid shear stress on the sand bed and methane ebullition rates. The findings reveal that biochemical factors significantly influence methane production, whereas shear velocity primarily affects methane ebullition. Sediment properties are identified as influential factors impacting both methane production and ebullition. Overall, this study establishes empirical relationships between bubble dynamics, the Weber number, and methane emissions, presenting a formula to estimate methane ebullition flux. Future research, incorporating specific conditions such as water depth, effective shear stress beneath the sediment's tensile strength, and organic matter, is expected to contribute to the development of biogeochemical and hydro-environmental impact assessment methods suitable for in-situ applications.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.4 s.117
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• pp.116-128
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• 2006

This study focuses on hydrological changes caused by developments in the 13th, 14th (Motjarigol) district in Eun Pyoung New Town, Seoul on the basis of the Land Use Planning of development plan. Through analyses from the hydrological experiments about rainfall outflow using universal equation and amounts of infiltration through soils, the changes in amounts of overflows were estimated and the results were discussed from a urban ecological point of view. As a result, it has been predicted that the amount of rainfall outflow at post-development was dramatically increased, compared to pre-development. Installing of Derbris Dams and infiltration facilities were suggested as alternative plan to meditigate these changes. If we apply these alternatives, the rainfall outflow would be reduced up to 30% compared to the development plan without BMPs (Best Management Practice). In conclusion, it is proposed that once the ecological principles were considered during development planning process, we can minimize the adverse effects of developments to our environments.

• Journal of Korean Society of Water and Wastewater
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• v.8 no.1
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• pp.27-33
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• 1994

With the rapid industrialization, an ever-increasing quantity and kind of new organic compounds pose environmental problems due to their toxicity and physiological effect. However, research on the biodegradation of these compounds under anaerobic condition is very limited inspite of its efficiency and economical advantage. In this research, the pH effect on the ring cleavage of phenol under anaerobic condition was investigated, and the theory of phase separation was applied to the degradation of phenol for investigating the role of acidogenic bacteria. Results, obtained from biochemical methane potential(BMP) assay for 15.5 days of incubation, showed that acidic condition was more desirable for phenol degradation than alkaline condition. By both unacclimated methanogenic granular sludge and two mixed cultures, phenol was completely removed within six weeks of incubation with a gas conversion rate of over 86% of theoretical one. However, phenol was not degraded by unacclimated acidogenic culture, and thus it is considered as a syntrophic substrate. In case of phase separated biochemical methane potential(PSBMP) assay, in which acidogenic and methanogenic culture were seeded separately and consecutively, those that had been subjected to normal acidogens for 3 to 4 weeks showed higher gas production than those seeded with sterile or frozen culture.

• Journal of Technologic Dentistry
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• v.36 no.3
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• pp.179-184
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• 2014

Purpose: This study was performed to investigate the release behavior of bioactive materials as a BMP-2 embedding on the porous titanium implant. Methods: Porous Ti implant samples were fabricated by sintering of spherical Ti powders in a high vacuum furnace. Specimens diameter and height were 4mm and 10mm. Embedding materials were used to stamp ink. Sectional images, porosity and release behavior of porous Ti implants were evaluated by scanning electron microscope(SEM), mercury porosimeter and UV-Vis-NIR spectrophotometer. Results: Internal pore structure was formed fully open pore. Average pore size and porosity were $8.993{\mu}m$ and 8.918%. Embedding materials were released continually and slowly. Conclusion: Porous Ti implant was fabricated successfully by sintering method. Particles are necking strongly each other and others portions were vacancy. Therefore bioactive materials will be able to embedding to porous Ti implants. If the development of the fusion implant of the bioactive material will be able to have the chance to several patients.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.23-31
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• 2009

To compare the effects of nanometer-sized silver ions and support materials (nano-silver coating material, NM-silver) and silver ions, we exposed zebrafish embryos to both types of nano-silver ions and compared the acute responses during embryogenesis. The amount of silver in the NM-silver (17.16%) was greater than that in the silver ion (4.56%). Both of these materials have different atomic compositions. The silver ion-exposed groups (10 and 20 ppt) showed lower survival rates than the NM-silver-exposed groups (10 and 20 ppt). NM-silver penetrated the skin and blood tube of zebrafish larvae as aggregated particles, whereas, silver ions penetrated the organelles, nucleus and yolk in a spread-out pattern. Micro-array analysis of RNA from zebrafish larvae (72 hours post-fertilization) that were treated with either NM-silver or silver ions, showed alteration in expression of the BMP, activin, TGF-$\beta$, and $GSK3{\beta}$ genes pathway. Additionally, $GSK3{\beta}$ gene pathway for apoptosis that was related with left-right asymmetry. Gene expression changes in the NM-silver or silver ions-treated zebrafish embryo led to phenotypic changes in the hatched larvae, reflecting increased apoptosis and incomplete formation of an axis.

• The Journal of the Korean dental association
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• v.54 no.4
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• pp.274-283
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• 2016

Bisphosphonates are widely used mainly for the treatment of osteoporosis and bone metastasis of malignancy. Since the first report of MRONJ, there have been many studies associated, however the pathogenesis of MRONJ is not yet clear. Medication-related osteonecrosis of the jaws (MRONJ) is a serious complication associated with long-term medication therapy. It is characterized by exposed necrotic bonein the jaw, which has persisted for more than 8weeks despite continuous treatment by dentist. The mechanism of development of MRONJ is still unclear and there is no definitive standard treatment for MRONJ. The purpose of this study is to investigate the jaw bone destruction mechanism of accumulated bisphosphonates, so that we can develop therapeutic method to repair the defect and stop the destruction process. The authors performed simultaneous application of PRF(Platelet rich fibrin) and BMP-2(Bone morphogenetic protein-2) to stimulate not only soft tissue healing but also osseous regeneration. Our case series demonstrate that simultaneous application of platelet rich fibrin and bone morphogenetic protein-2 can be a treatment of choice for MRONJ.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.514-517
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• 2009

Anaerobic biodegradability(AB), which can be determined with the ultimate methane yield by the decomposition of organic materials, is one of the important parameters for the design and the operation of anaerobic digestion plant. In this study, Biochemical Methane Potential(BMP) test has been carried out to evaluate the methane yield of agro-industrial biomasses such as cattle manure, Italian ryegrass(IRG), Oats, Rye and Barley as the forage crops, Rush, the sludges produced from milling and slaughterhouse wastewater treatment plant(SMWTP, SSWTP). In the condition of thermophilic anaerobic digestion, the ultimate methane yield and anaerobic biodegradability of forage crops ranged from 0.367 to $0.452LCH_4$/gVS of methane yield with AB having the range of about 77.0 to 87.3%. On the other hand, that of other substrate showed low figures compared with the forage crops because of low VS content and C/N ratio. Therefore, the forage crops could be used as a good substrate to produce much more the methane in anaerobic digestion.