• 대한화장품학회지
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• 제34권1호
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• pp.1-8
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• 2008

피부장벽을 포함한 표피층은 인체의 조직 가운데에서도 가장 역동적인 기관이다. 다시 말해서 끊임없이 새로운 표피세포의 형성, 분화 및 탈각과정이 반복되면서 표피항상성(epidermal homeostasis)을 유지한다. 표피항상성은 피부기능 가운데 가장 주요한 기능인 permeability barrier homeostasis의 확립으로 연결된다. Permeability barrier homeostasis는 각질층에서 이루어지며 이를 형성하고 유지하기 위해 매우 정교하게 조절되어야 한다. 표피항상성을 조절하는 핵심 조절인자로서 nuclear hormone receptor(NHR)가 중심에 있음이 최근 다양한 연구를 통해 입증되었다. 이들은 각질세포 특이적인 단백질, 즉, involucrin, loricrin 및 trans-glutaminase 1(TG 1) 등의 발현을 유전자 수준에서 조절할 뿐 아니라 표피 지질성분의 생합성을 증가시키는 등 피부장벽을 구성하는 brick 및 mortar의 생성과 유지에 핵심적 역할을 하는 것으로 알려졌다. NHR 가운데 peroxisome proliferator activator receptor(PPAR)와 liver X receptor(LXR)의 activator/ligands가 리놀레인산 등 지방산, leukotriene, prostanoid 및 oxygenated sterol 등이 지질대사과정에서 형성된 지질 종류인 까닭에 liposensor로도 알려지고 있다. 따라서 liposensor들을 비롯한 PPAR과 LXR activator/ligands들은 피부장벽기능이 저해된 아토피성 피부를 포함하여 건조피부를 관리하는 epidermotherapy의 수단으로서 잠재적 가능성이 있다고 생각된다.

• Nuclear Engineering and Technology
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• 제43권6호
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• pp.557-566
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• 2011

A cold spray coating (CSC) of copper was studied for its application to a high-level radioactive waste (HLW) disposal canister. Several copper coatings of 10 mm thick were fabricated using two kinds of copper powders with different oxygen contents, and SS 304 and nodular cast iron were used as their base metal substrates. The fabricated CSC coppers showed a high tensile strength but were brittle in comparison with conventional non-coating copper, hereinafter defined to as "commercial copper". The corrosion behavior of CSC coppers was evaluated by comparison with commercial coppers, such as extruded and forged coppers. The polarization test results showed that the corrosion potential of the CSC coppers was closely related to its purity; low-purity (i.e., high oxygen content) copper exhibited a lower corrosion potential, and high-purity copper exhibited a relatively high corrosion potential. The corrosion rate converted from the measured corrosion current was not, however, dependent on its purity: CSC copper showed a little higher rate than that of commercial copper. Immersion tests in aqueous HCl solution showed that CSC coppers were more susceptible to corrosion, i.e., they had a higher corrosion rate. However, the difference was not significant between commercial copper and high-purity CSC copper. The decrease of corrosion was observed in a humid air test presumably due to the formation of a protective passive film. In conclusion, the results of this study indicate that CSC application of copper could be a useful option for fabricating a copper HLW disposal canister.

• 대한본초학회지
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• 제29권2호
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• pp.61-67
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• 2014

Objectives : Aconiti Lateralis Preparata Radix (Aconitum Carmichaeli, AC) and Cinnamomi Cortex (Cinnamomi Cortex, CC) have been treated to elderly for kidney yang enhancement in Korean traditional medicine. In this study, the effects of water extract of AC and CC on RANKL (Receptor Activator for Nuclear Factor ${\kappa}B$ Ligand)-induced osteoclast differentiation were evaluated in culture system. Methods : MTT assay was used to evaluate the potential cytotoxicity of AC and CC extracts in bone macrophage marrows (BMMs) stimulated with M-CSF. TRAP (tartrate-resistant acid phosphatase) staining and TRAP activity were performed to know the inhibitory effect on osteoclast differentiation. The protein expression levels of nuclear factors such as activated T cell(NFAT)c1, c-Fos, MAPKs and ${\beta}$-actin in cell lysates treated with AC and CC extracts were analysed by western blotting. Results : AC, CC extracts and their co-administration inhibited significantly RANKL-induced osteoclast differentiation in BMMs in a dose dependent manner without toxicity. Each AC and CC extracts inhibited the phosphorylation of p38. Also, AC and CC extracts, respectively, inhibited the protein expression of c-Fos and NFATc1 more than Co-administration of AC and CC even if all treatments did. It was observed that RANKL-induced degradation of I-${\kappa}B$ is significantly suppressed by all treatments. Conclusions : Taken together, It was concluded that AC and CC have beneficial effect on osteoporosis by inhibition of osteoclast differentiation. Thus, Atractylodis AC and CC could be a treatment option for osteoporosis.

• Nuclear Engineering and Technology
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• 제56권7호
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• pp.2842-2849
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• 2024

The amorphous glasses containing PbO, ZnO, MgO, and B₂O₃ have been fabricated using the melt quenching technique. The structural properties have been analysed using the Fourier-transform infrared (FTIR) and Raman spectroscopy. Derivative of Absorption Spectra Fitting (DASF) method have been used to estimate the band gap energy from the UV-Vis absorption data which decreases from 3.02 eV to 2.66 eV with increasing the concentration of the PbO.The four glass samples 0.284 and 0.826 MeV showed unique variations in terms of gamma attenuation ability. LZMB4 glass sample proved to be the mist effective in terms of shielding of gamma radiation as it requires little distance compared to LZMB3, LZMB2 and LZMB1 to attenuate. RPE revealed a raise with increase in the thickness of the material and reduces as the energy raises. TF is superior in LZMB1 compared to LZMB2, LZMB3 and LZMB4, confirming that, LZMB4 will attenuate better. The Z_Eff of the materials was seen falling as the energy increases, confirming that the linear attenuation coefficient of the glass materials decreases when the energy is increased. The results confirmed that, glass material LZMB4 is the best option especially for gamma radiation shielding applications compared to LZMB3, followed by LZMB2, then LZMB1.

• 한국대기환경학회지
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• 제28권5호
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• pp.556-570
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• 2012

The Low Carbon Path Calculator is an excel-based model to project greenhouse gas emissions from 2009 to 2050, which is based on the 2050 Pathways Calculator developed by the UK Department of Energy and Climate Change (DECC). Scenarios are developed to reduce GHG emissions in Korea at 50% based on 2005 levels by 2050 using a Low Carbon Path Calculator. They were classified in four different cases, which are high renewable, high nuclear, high CCS and mixed option scenarios. The objectives of this study are to compare scenarios in terms of GHG emissions, final energy, primary energy and electricity generation and examine the usefulness of that model in terms of identifying pathways towards a low carbon emission society. This model will enhance the understanding of the pathways toward a low carbon society and the level of the climate change policy for policy makers, stakeholders, and the public. This study can be considered as a reference for developing strategies in reducing GHG emissions in the long term.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2002년도 춘계 학술발표회 논문집
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• pp.135-141
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• 2002

PWR에의 토륨 핵연료 운용방안의 하나로 제안되었던 KTF 설계안을 바탕으로, APR-1400 노심에 맞게 설계변수에 빠른 최적화를 수행하였다. 최적화 방향은 핵확산 저항성 증대와 경제성 제고를 목표로 하였으며 최적화의 설계 기준은 핵확산 저항성의 경우 SNS, TG, BCM, Toxicity를 기준으로 하고 경제성은 FEI라는 새로운 지수를 사용하여 두 가지 모두 최대가 되는 방향으로 최적화하였다. 최적 설계안을 이용하여 APR-1400의 노심을 설계하는 과정을 여러 측면에서 검토하였으며, 비균질 노심에 토륨핵연료집합체를 사용한 설계안이 안전성 및 경제적 타당성을 갖음을 확인하였다.

• 전기학회논문지
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• 제67권2호
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• pp.173-178
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• 2018

This study organizes scenarios on the power supply and demand plans considering the uncertainties and the portion of distributed energy resources. In analysing the scenarios, it estimates total electricity supply cost in the social aspect, natural gas demand and air pollutants emission including carbon dioxide. Also the analysis is performed to estimate the marginal cost of carbon dioxide reduction for the fuel switching from coal to liquified natural gas. In result, the social cost could be decreased by replacing some portion of renewable energy by LNG-based combined heat and power and delaying the construction of large base-load generators such as coal and nuclear plants. The marginal carbon dioxide reduction cost by fuel switching is in plausible range for fuel switching to be an option for carbon dioxide emission reduction when the social cost is considered.

• 한국자기공명학회논문지
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• 제10권1호
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• pp.74-88
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• 2006

Since the first commercial NMR spectrometer came out in 1953 from Varian, much of the hardware development has been improved and matured through commercial equipments. Many of magnetic resonance laboratories however still build and use home-built spectrometers, which are satisfactory even with the consideration of educational purpose only. The home-built NMR spectrometer could be further advantageous and could be often an only option for investigating new ideas with demanding experimental conditions or new hardware support. A solid state NMR spectrometer was designed with extra interest in stochastic experiment and built for an 8.93 T superconducting magnet from Oxford instrument. Super-heterodyned system was implemented for the transmitter and receiver parts. Intermediate frequency (IF) for the heterodyne system was chosen to 70 MHz for the first and the second channels, with additional 120 MHz for the third channel for maximum NMR frequency capability. We will show overall schematics, and discuss the designs with detailed diagrams, then demonstrate the applicability of home-built spectrometer with stochastic-excitation in solid state NMR and in applications to quadrupolar nuclear Spins.

• 생약학회지
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• 제46권4호
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• pp.295-302
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• 2015

Cynanchi wilfordii Radix roots have been utilized as traditional medicine for variety of diseases including diabetes mellitus, aging progression and scavenging free radicals, enhancing immunity, reducing high serum cholesterol, and anti-tumor activity. However, the mechanisms underlying this effect remain poorly understood. The principal objective of this study was to determine the effect of cynandione A on osteoclast cells. Thus, we was isolated cynandione A from Cynanchi wilfordii Radix roots and evaluated the effect of cynandione A on receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL)-induced osteoclast differentiation. We found that cynandione A significantly inhibited osteoclast differentiation stimulated-RANKL in RAW 264.7 cells. Cynandione A conspicuously inhibited the mRNA and protein expression of matrix metallopeptidase 9 (MMP-9), tartrate-resistant acid phosphatase (TRAP) in cynandione A treated with RANKL. Taken together, our results demonstrated that Cynanchi Wilfordii Radix may be useful treatment option of bone-related disease such as osteoporosis leads to fracture of bone and rheumatoid arthritis.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제20권4호
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• pp.259-262
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• 2017

Mitochondria play essential role in eukaryotic cells including in the oxidative phosphorylation and generation of adenosine triphosphate via the electron-transport chain. Therefore, defects in mitochondrial DNA (mtDNA) can result in mitochondrial dysfunction which leads to various mitochondrial disorders that may present with various neurologic and non-neurologic manifestations. Mutations in the nuclear gene polymerase gamma (POLG) are associated with mtDNA depletions, and Alpers-Huttenlocher syndrome is one of the most severe manifestations of POLG mutation characterized by the clinical triad of intractable seizures, psychomotor regression, and liver failure. The hepatic manifestation usually occurs late in the disease's course, but in some references, hepatitis was reportedly the first manifestation. Liver transplantation was considered contraindicated in Alpers-Huttenlocher syndrome due to its poor prognosis. We acknowledged a patient with the first manifestation of the disease being hepatic failure who eventually underwent liver transplantation, and whose neurological outcome improved after cocktail therapy.