• 호남수학학술지
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• 제29권3호
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• pp.327-339
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• 2007

Approximate fibrations form a useful class of maps. By definition fibrators provide instant detection of maps in this class, and PL fibrators do the same in the PL category. We show that every closed s-hopfian t-aspherical manifold N with some algebraic conditions and X(N) $\neq$ 0 is a codimension-(2t + 2) PL fibrator.

• 제품안전
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• 2호통권146호
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• pp.49-49
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• 2006

지난 1월중 이루어진 PL상담건수는 모두 28건이었으며, PL상담록과 제품별 회의내용 중에서 특히 중요하다고 여겨지는 사안을 발췌하여 여기에 게재하오니 전기용품제조업체 및 수입업체는 물론 소비자 여러분의 많은 참고가 있기를 기대합니다.

• 한국식품영양과학회지
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• 제37권2호
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• pp.154-161
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• 2008

상황버섯의 지방소화효소 억제와 항산화 활성을 구명하기 위해 상황버섯 메탄올 추출물의 췌장 lipase 억제 활성과 항산화 활성을 in vitro에서 측정하고, 흰쥐에 고지방식이와 함께 상황버섯 분말을 투여하여 지방소화효소 활성 저해를 통한 지방 흡수 억제와 항산화 효과를 in vivo에서 관찰하였다. 메탄올 추출물의 췌장 지방소화효소 활성 저해능과 DPPH 라디칼 소거능을 측정한 결과, $IC_{50}$가 각각 $36.3\;{\mu}g/mL$와 $20.1\;{\mu}g/mL$로 나타났으며, DPPH 소거능은 비타민 C의 $IC_{50}$인 $18.3\;{\mu}g/mL$와 비슷하였다. 상황버섯 분말을 고지방식이에 각각 2%와 5% 첨가한 식이를 공급하고 8주간 사육한 결과, 상황버섯 첨가로 인해 식이섭취량은 증가하였으나 체중과 체지방량에는 차이가 없었으며 따라서 식이효율은 낮았지만 유의적이지는 않았다. 그러나 상황버섯 섭취로 인해 지질의 흡수가 감소되어 분변으로의 지질 배설량이 증가한 것으로 조사되었다. 혈장 지질의 경우, 상황버섯 첨가군에서 혈장 총 콜레스테롤과 LDL 콜레스테롤, 간의 총 지질과 총 콜레스테롤 함량이 대조군에 비해 낮아진 것으로 조사되었다. 혈장 GPT 활성은 상황버섯 2%와 5% 첨가군에서 각각 대조군에 비해 43%와 45% 감소하였다. 혈장, 적혈구 및 간의 항산화 효소 활성을 측정한 결과, 상황버섯의 첨가로 T-SOD 활성은 영향을 받지 않았으나, GSH-Px는 간과 혈장에서 활성이 증가하였다. 실험식이를 공급하고 2주, 4주 및 8주에 림프구를 분리하여 DNA 손상 정도를 측정한 결과, 상황버섯을 2주간 섭취한 후의 림프구 DNA 손상이 대조군에 비해 큰 것으로 조사되었으나, 4주간 섭취한 군에서는 차이가 없었고, 8주에서는 DNA 손상이 억제되었으며 2% 첨가군에서 DNA 손상 억제 정도가 가장 크게 나타났다. 림프구에 $H_2O_2$로 산화스트레스를 가하고 DNA 손상 정도를 측정한 결과, 상황버섯 첨가군의 DNA 손상이 대조군에 비해 식이섭취기간에 비례해서 낮아졌고, 5% 첨가보다는 2% 첨가군에서 억제 효과가 더 높은 것으로 조사되었다. 이상의 결과들로부터, 상황버섯은 생체 내 항산화 효소계의 활성유도와 산화스트레스로 인해 생성된 라디칼의 활발한 소거를 통해 세포의 산화적 손상을 억제하는 효과가 있는 것으로 생각된다.

• 대한본초학회지
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• 제27권6호
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• pp.7-13
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• 2012

Objectives : Reactive oxygen species (ROS) have been associated with pathogenic processes including carcinogenesis through direct effect on DNA directly and by acting as a tumor promoter. Therefore, it has been regarded that ROS may be a major target for cancer prevention. The root of Paeonia lactiflora pall (PL), a traditional Chinese herb, has been a component of effective prescriptions for treatment of liver disease. Also, there are some reports about the antioxidant activities of the extracts from PL. However, little has been known about the effects of PL against oxidative damage. This work aimed to elucidate the anti-oxidant effects of Paeonia lactiflora pall (PL) in the non-cellular system and cellular system. Methods : Antioxidant activities of PL were evaluated by hydroxyl radical scavenging assay and $Fe^{2+}$ chelating assay. Anti-oxidative effect of PL was evaluated by ${\varphi}X$-174 RF I plasmid DNA cleavage assay in non-cellular system. In addition, DNA migration assay, expression level of phospho-H2AX, MTT assay and lipid peroxidation assay were performed for evaluate the anti-oxidative effect of PL in cellular system. Results : PL had a dose-dependent hydroxyl radical scavenging and $Fe^{2+}$ chelating capacity. In addition, PL inhibited oxidative DNA and cell damage induced by hydroxyl radical in non-cellular system and cellular system. Conclusion : Taken together, P. lactiflora pall may be possible for the application to a potential drug for treating the oxidative diseases such as cancer.

• 한국안전학회지
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• 제20권2호
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• pp.140-145
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• 2005

The PL(Product Liability) Law has been going into effect in Korea since July 2002. Accordingly, a company's responsibility for customers who are damaged by the defect in the product safety has been gradually strict and imposed burden on management. Not only general consumers but also labors who work with machine in the field of production are included in the concept of victim of the PL Law. That is to say, when a worker is damaged by the defect of machine he can institute a PL lawsuit more aggressively, not just get the industrial accident compensation as usual, only if not his own fault but the defect of machine used in the course of production can be demonstrated. This paper intends to present suggestions to PL prevention of manufacturing companies of industrial machine through the case research of PL accidents in the area of industrial safety.

• 설비공학논문집
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• 제14권2호
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• pp.91-97
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• 2002

The present study concerns an experiment on the supply-air control in variable air volume (VAV) system with a Pl control logic. A thermal chamber with a Pl control logic is constructed to verify the previously suggested multi-zone model. The stratified thermal model is adopted in the control logic for a thermal chamber cooling test. The effects of taler- mal parameters and control parameters such as supply air temperature and Pl control factor are investigated by implementing the thermal chamber cooling test. The experimental results obtained show that the transient behavior of the air-conditioned space temperature are in good agreement with the simulation results of the stratified thermal model.

• 한국항공우주학회지
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• 제36권1호
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• pp.39-47
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• 2008

GPS에 의사위성(PL: Pseudolite)을 추가하여 고도 정확도를 향상시키면 무인 항공기의 착륙 성능이 향상된다. 그러나 GPS 위성이 계속 움직이고, 매번 착륙 위치가 바뀌는 환경에서 원하는 정확도를 얻을 수 있도록 의사위성을 설치하고 운영하는 것은 매우 어려운 일이다. GPS와 의사위성으로 얻을 수 있는 서비스의 범위와 측위 정확도는 시뮬레이터로 예측 가능하고 정확하게 예측된 정보는 무인항공기의 운영을 위하여 매우 중요하다. 본 논문에서는 효과적인 의사위성의 활용을 위하여 GPS/PL 시뮬레이터를 개발하고 그 성능을 평가하였다. 시뮬레이터의 서비스 범위 예측은 의사위성의 설치 위치 및 개수, 송신 전력과 무인 항공기의 고도를 고려하여 GIS 데이터와 광선 방출 기법을 이용하여 계산하였다. 측위 정확도는 GPS와 의사위성을 동시에 사용하여 구한 DOP와 NSP를 이용하여 분석하였다. 실제 수신기의 출력과 비교하여 구현된 시뮬레이터를 검증하였으며, 시뮬레이션 결과 2개 이상의 의사위성의 추가로 무인항공기의 자동 착륙에서 요구되는 정확도를 만족시킬 수 있음을 확인하였다.

• Applied Science and Convergence Technology
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• 제24권3호
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• pp.67-71
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• 2015

InP/InGaP quantum structures (QSs) were grown on GaAs (001) substrates by a migration-enhanced molecular beam epitaxy method. Temperature-dependent photoluminescence (PL) and emission wavelength-dependent time-resolved PL (TRPL) were performed to investigate the optical properties of InP/InGaP QSs as a function of migration enhanced epitaxy (MEE) growth cycles from 2 to 8. One cycle for the growth of InP QS consists of 2-s In and 2-s P supply with an interruption time of 10 s after each source supply. As the MEE growth cycle increases from 2 to 8, the PL peak is redshifted and exhibited different (larger, comparable, or smaller) bandgap shrinkages with increasing temperature compared to that of bulk InP. The PL decay becomes faster with increasing MEE cycles while the PL decay time increases with increasing emission wavelength. These PL and TRPL results are attributed to the different QS density and size/shape caused by the MEE repetition cycles. Therefore, the size and density of InP QSs can be controlled by changing the MEE growth cycles.

• 한국식품영양과학회지
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• 제20권5호
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• pp.473-478
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• 1991

After the glycolipid(GL) and phospolipid (PL) of flint corn during a growth process were fractionated by silicic acid column chromatography (SACC), the GL and PL of polar lipids were separated by thin layer chromatography (TLC)and quantitative by TLC scanner and the fatty acid composition in polar lipids were determined by gas chromatography (GC). Of the GL in polar lipids were separated by TLC, monoglycosyl diacylglycerol (8.3~29.2%) was the major component, and monoglycosyl ceramide, monoglycosyl sterol were also found as minor components. Of the PL, phosphatidyl choline (27.2~29.5%) and phosphatidyl inositol (42.9~79.1%) were the major components, and phosphatidyl ethanolamine and cardiolipin were also persont in the PL. The major fatty acids in the GL were oleic(27.1~37.1%), linoleic (13.2~35.7%) and palmitic (22.5~25.6%) acids. The major fatty acids in the PL were palmitic (46.5~52.3%), heptadecanoic (23.0~25.1%) and oleic(7.2~14.6%) and GL contained a higher percentage of unsa-turated fatty acids, but PL presented that of the saturated fatty acids.

• 동의생리병리학회지
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• 제25권5호
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• pp.843-848
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• 2011

In Korea, China, and Japan, Paeonia lactiflora Pall (PL) has been used in the treatment of rheumatoid arthritis, hepatitis, and fever for more than 1200 years. It has been reported that PL has protective effects against $H_2O_2$-induced oxidative stress and LPS-induced liver inflammation. However cellular and molecular mechanism of PL protection against oxidative stress has not fully been elucidated. Here, we describe that the water-soluble extract of PL decreased $H_2O_2$-induced hepatotoxicity. This hepatoprotective effect of PL is reason to decrease the level of intracellular reactive oxygen species (ROS) and increase expression of heme oxygenase 1 (HO-1) and heat shock protein 72 (HSP72) which proteins are involved in protecting the cells from stress like as oxidative stress. We also elucidated that hepatoprotective effect of PL was abolished by knock down of HO-1 and HSP72 by siRNA. These results suggest that the increasing of HO-1 and HSP72 protein by PL treatment might be participated in hepatoprotective effect against oxidative stress such as $H_2O_2$.