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Protective Effects of Gamipalmi-hwan on Elastase-induced Apoptosis of A549 Cells (가미팔미환(加味八味丸)의 elastase 유도성 A549 세포사멸에 대한 보호효과)

  • Oh, Ji-Seok;Park, Yang-Chun
    • The Journal of Korean Medicine
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    • v.31 no.2
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    • pp.137-148
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    • 2010
  • Objective: This study aimed to evaluate the protective effects of Gamipalmi-hwan (GPH) on elastase-induced lung cell injury. Materials and Methods: As an in vitro model of emphysema, the current study was performed to investigate potential activity of GPH in regulating injury responses of A549 human type II cell line mediated by elastase treatment. Results: GPH treatment increased the number of A549 cells which was reduced by elastase digestion. Elastin protein level, which was reduced by elastase treatment, was increased by GPH treatment. Labeling intensity with caspase 3 protein in elastase-treated cells was reduced by GPH treatment. Both Erk1/2 and Cdc2 protein levels, which were decreased by elastase treatment, were increased to a level similar to that of the normal cells. mRNA levels encoding IL-$1{\beta}$ and TNF-$\alpha$ were increased by elastase and then down-regulated by GPH. Conclusion: The present data suggest that A549 cells are subjected to inflammatory damage by elastase and can be recovered by GPH treatment. Further studies examining the protective activity of GPH in elastase-treated lung tissue would be useful for therapeutic strategies of emphysema treatment.

A Study on the Combustion Characteristics of Biomass using Cone- calorimeter (I) : the Case of Maple Leaves, Gingko Leaves, Bush, Pine Needles (콘 칼로리미터를 이용한 바이오매스의 연소특성에 관한 연구(I) - 단풍잎, 은행잎, 덤불, 솔잎에 대해서 -)

  • Park, Byung-Hyun;Park, Duck-Shin;Cho, Young-Min;Park, Eun-Young;Lee, Cheul-Kyu
    • Journal of Korean Society for Atmospheric Environment
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    • v.21 no.4
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    • pp.459-469
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    • 2005
  • In recent years, concerns have been growing globally regarding greenhouse gases. Open burning of biomass causes emission of a number of greenhouse and other gases and substances. This paper studied an analysis on the characteristics of four types of biomass using duel type cone calorimeter. Cone calorimeter is widely used for assessing combustibility of materials in Europe. As a result, we evaluated several characteristics of biomass, such as heat released rate, smoke production rate, CO, $CO_2$ production and mass loss rate, and so on. $CO_2$ is currently responsible for over $60\%$ of the enhanced greenhouse effect, and may be the most important contributor to future. $CO_2$ production for biomass in the range of $1.74\~1.99kg/kg$ is similar to previous research conducted by Bhattacharya et al. (2002a).

Technology Trends and Prospects of Silicon Solar Cells (실리콘 태양전지의 기술현황 및 전망)

  • Park, Cheolmin;Cho, Jaehyun;Lee, Youngseok;Park, Jinjoo;Ju, Minkyu;Lee, Youn-Jung;Yi, Junsin
    • Current Photovoltaic Research
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    • v.1 no.1
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    • pp.11-16
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    • 2013
  • The current solar cell industry is experiencing a temporary plateau due to a sluggish economy and oversupply. It is expected that the solar industry can see similar growth to that of the recent past by overcoming the current situation, as there is growing demand globally for solar energy. The current situation led to restructuring of the world's solar industry, and domestic firms will need to have competitiveness through strategic approaches and proprietary technology to survive in the global solar market. Crystalline and amorphous silicon based solar cells have led the solar industry and occupied half or more of the market thus far. They will do so in the future PV market as well by playing a pivotal role in the solar industry. In this paper, the current status and prospects of silicon based solar cells, from materials to comprehensive and high efficiency technology that can emerge in the future, are discussed.

A study of Sedimentation Processes of Saemangeum Reclamation( I ) - A study of Sedimentation Processes before Saemangeum Reclamation - (새만금간척 퇴적과정에 관한 연구( I ) -새만금간척 시행 전을 중심으로-)

  • Shin, Moon-Seup
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.44 no.4
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    • pp.62-74
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    • 2002
  • The purpose of this study is to find the variation of sedimentation patterns before Saemangeum reclamation. Residual flow before Saemangeum reclamation was calculated diagnostically from the observed water temperature and salinity data in May 1992 by the Marine Development Institute of Kunsan National University and wind data which were obtained from spring 1969 through winter 1977 by the Gunsan Meteorological Observatory. Three dimensional movements of injected particles due to currents, turbulence and sinking velocity are tracked by the Euler-Lagrange method. Calculated sedimentation patterns of riverine materials are highly similar to the observed ones. When suspended sediments with the size of soil grain of 60 ${\mu}m$ are injected from the Mangyeong River, their dispersion range of sediment is about 25km for 24 hours after the injection, while about 35km for 72 hours after the injection. When suspended sediments with the size of soil grain of 200 ${\mu}m$ are injected, their dispersion range of sediment is about 18km for 24 hours after the injection, while about 21km for 72 hours after the injection.

Growth Response to a GH-Autotransgenesis in Common Carp Cyprinus carpio

  • Noh, Choong-Hwan;Kim, Dong-Soo
    • Fisheries and Aquatic Sciences
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    • v.15 no.1
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    • pp.37-41
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    • 2012
  • Autotransgenic manipulation with a growth hormone (GH)-construct is a potential approach to improving the growth rates of farmed fish. Here, we present the generation of GH-autotransgenic common carp Cyprinus carpio carrying a transgene comprised of the carp homologous GH gene and a ${\beta}$-actin regulator. Autotransgenic carp showed similar viability to their non-transgenic siblings. Early growth characteristics of founder autotransgenic carp up to 50 days postfertilization were highly variable among individuals; i.e., some fish exhibited significant growth depression, while others showed dramatic acceleration of growth, achieving greater than sixfold increases in body weight relative to their non-transgenic counterparts. Stimulated growth performance became more notable with age and many transgenic individuals of the largest class reached 5 kg within 8 or 9 months, which is at least 10 times heavier than the average body weight of communally grown non-transgenics. Four of six founder transgenic males were successful in passing the transgene to their $F_1$ offspring with frequencies ranging from 19 to 36%. Growth stimulations were also persistent in all $F_1$ progeny groups examined.

Enamel matrix derivative for replanted teeth in animal models: a systematic review and meta-analysis

  • Kim, Sahng G.;Ryu, Steven I.
    • Restorative Dentistry and Endodontics
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    • v.38 no.4
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    • pp.194-203
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    • 2013
  • Objectives: To investigate the effect of enamel matrix derivative (EMD) on periodontal healing of replanted teeth in animal models. Materials and Methods: The authors searched MEDLINE, PubMed, EMBASE, Cochrane Library, Web of Knowledge and Scopus for articles published up to Oct 2012. Animal studies in which EMD was applied in transplanted or replanted teeth with adequate controls and histological data were considered. Normal periodontal healing or root resorption determined by histology after EMD was applied in replanted teeth with adequate controls was used as outcome measures. The following search strategy was used: ('Emdogain' OR 'enamel matrix proteins' OR 'enamel matrix derivative') AND ('avulsion' OR 'transplantion' OR 'autotransplantation' OR 'replantation'). Results: Six animal studies were included in the final review. There was great heterogeneity in study design among included studies. Two studies with similar study designs were identified and analyzed by a meta-analysis. The pooled estimates showed a significantly higher normal healing and surface resorption and significantly less inflammatory and replacement resorption in EMD-treated groups compared with non-EMD-treated groups. Conclusions: With the limitations of this systematic review, the use of EMD led to greater normal periodontal healing and surface root resorption and less inflammatory and replacement root resorption in the presence of periodontal ligaments. However, no definite conclusion could be drawn with regard to the effect of EMD on periodontal healing and root resorption when no periodontal ligaments exist.

Deposition of Super Hydrophobic a-C:F Films by Dielectric Barrier Discharge at Atmospheric Pressure

  • Kim, Duk-Jae;Kim, Yoon-Kee;Han, Jeon-Geon
    • Journal of Surface Science and Engineering
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    • v.44 no.2
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    • pp.50-54
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    • 2011
  • Hydrophobic a-C:F film was coated on polycarbonate film with $CF_4$, $C_2F_6$ and HFC ($C_2F_4H_2$) gas in helium discharge generated by 5~100 kHz AC power supply at atmospheric pressure and room temperature. The highest water contact angle of the a-C:F film formed with $He/C_2F_6$ mixed gas is $155^{\circ}$. X-ray photoelectron spectrum showed that there was 40% of C-$CF_3$ bond at the surface of the super hydrophobic film. The contact angle and deposition rate were decreased with increasing substrate temperature. The contact angle was generally increased with the surface roughness of the film. The contact angle was high when the surface microstructure of the film was fine and sharp at the similar roughness and chemical composition of the surface.

Model development to design modified atmosphere packaging of Mandarin oranges

  • Kim, Jong-Kyoung;Lee, Sang-Duk;Ha, Young-Sun;Lee, Jun-Ho
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.10a
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    • pp.192.1-192
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    • 2003
  • The aim of this study was to develop a model that could be used in the design of modified atmosphere packaging (MAP) for Mandarin oranges. Respiratory data at 5, 10, 20$^{\circ}C$ for mandarin oranges were gathered and altered for create useful respiration model. The maximum rate of oxygen uptake increased with increasing temperature. The packaging materials were conventional low density polyethylene and polypropylene with anti-fog, and anti-fungi treatments, and thickness was 30 $\mu\textrm{m}$ and 50 $\mu\textrm{m}$. Permeability tests were performed to find their oxygen, carbon dioxide, water vapor transmission rate as increases in temperature. Test results were then converted to logarithm format for MAP modeling. Optimum gas composition in the package system for fruits were set according to literature and upper or lower limits of oxygen and dioxide established. To predict gas composition at certain storage time, weight of fruits, film thickness, film type, and other variables, respiration rate was studied at various storage conditions. The validity of the model was tested experimentally by observing actual atmospheric changes inside packages. It is concluded that the strategy developed is of use in designing dynamic gas exchange MAP systems, and also has potential uses in similar agricultural products.

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Tensile Behaviour of Foamed Metal Matrix Composite Using Stochastic FE Model (통계적 유한요소모델을 이용한 발포된 금속기지 복합재료의 인장특성)

  • 전성식
    • Composites Research
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    • v.17 no.2
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    • pp.34-39
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    • 2004
  • In this paper, a modified and representative unit cell model was employed to study the tensile behaviour of closed-cell metallic foams with varying spatial density distribution as well as material imperfections. The density variation was assumed to follow a statistical probability distribution of the Gaussian type. A multiple cell finite element model, utilising the modified unit cell, was developed. The model exhibits deformation patterns similar to those observed in tensile testing. The nominal stress-strain curve obtained from quasistatic tensile of the foam was compared with experimental findings and was found to be in good agreement in the scheme of maximum strength only if the appropriate density distribution and volume fraction of internal imperfections are taken into account. Moreover, maximum tensile strength of the aluminium foam was found to be more sensitive to the volume fraction of imperfection than standard deviation of the density.

Chaff Echo Detecting and Removing Method using Naive Bayesian Network (나이브 베이지안 네트워크를 이용한 채프에코 탐지 및 제거 방법)

  • Lee, Hansoo;Yu, Jungwon;Park, Jichul;Kim, Sungshin
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.10
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    • pp.901-906
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    • 2013
  • Chaff is a kind of matter spreading atmosphere with the purpose of preventing aircraft from detecting by radar. The chaff is commonly composed of small aluminum pieces, metallized glass fiber, or other lightweight strips which consists of reflecting materials. The chaff usually appears on the radar images as narrow bands shape of highly reflective echoes. And the chaff echo has similar characteristics to precipitation echo, and it interrupts weather forecasting process and makes forecasting accuracy low. In this paper, the chaff echo recognizing and removing method is suggested using Bayesian network. After converting coordinates from spherical to Cartesian in UF (Universal Format) radar data file, the characteristics of echoes are extracted by spatial and temporal clustering. And using the data, as a result of spatial and temporal clustering, a classification process for analyzing is performed. Finally, the inference system using Bayesian network is applied. As a result of experiments with actual radar data in real chaff echo appearing case, it is confirmed that Bayesian network can distinguish between chaff echo and non-chaff echo.