• Corrosion Science and Technology
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• 제6권3호
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• pp.128-132
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• 2007

For a quantitative inspection on the performance of weathering steel bridges, we have investigated the relationship between the corrosion rate and the composition of the rust layers formed on weathering steel bridges located in various environments in Japan and applied a protective ability index (PAI) to the bridges. The corrosion rates were clearly classified by the PAI, ${\alpha}/{\gamma}*$ and sub index of $({\beta}+s)/{\gamma}*$, where $\alpha$, \gamma*, $\beta$ and s are the mass ratio of crystalline $\alpha-FeOOH$, the total of $\gamma$-FeOOH+ $\beta$-FeOOH + the spinel-type iron oxide (mainly $Fe_3O_4$), $\beta-FeOOH$ and spinel-type iron oxide, analyzed by powder X-ray diffraction, respectively. In the case of ${\alpha}/{\gamma}$*>1, the rust layer works protective enough to reduce the corrosion rate less than 0.01 mm/y. The sub index $({\beta}+s)/{\gamma}*$<0.5 or >0.5 classifies the corrosion rate of the non-protective rust layers, therefore the former state of the rust layer terms inactive and the latter terms active. The quantitative inspection of a weathering steel bridge requires a performance-inspection (PI) and periodical deteriorationinspections (DI). The PI can be completed by checking of the PAI, ${\alpha}/{\gamma}*$. The DI on the weathering steel bridges where deicing salt is sprinkled can be performed by checking the PAI, $({\beta}+s)/{\gamma}*$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.366-368
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• 2003

In this paper, a parametric evaluation method of protection ability is proposed. The adequacy of every parameter is evaluated for the setting rules. Then the results are combined to give protection level of a whole protective system. The setting rules are categorized into three groups for hierarchical calculation. The proposed scheme is applied to a location problem of a new protective device to show its effectiveness.

• Journal of Korean Vacuum Science & Technology
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• 제6권2호
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• pp.105-107
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• 2002

a-C:H films were coated on windows of mobile telephone by RF plasma chemical vapor deposition equipment made in our company. Thickness of the coatings is about 0.7 micrometers and they have high hardness, low friction coefficient, good adhesion, high optical transparency and chemical inertness. Knoop hardness of the diamond-like carbon films on glass substrate is 2328 kg/mm$^2$. The adherence between films and substrate is good and shows to be 69 N by scratching test. The optical performance is improved obviously owing to coat the film on it. The index of the coated windows is 2.5, transmission of visible light is larger than 90%, and transmission of ultraviolet light decreases by 30% and the ultraviolet light can be obstructed obviously. The coated glass also has self-clean effect and decontamination ability. The films have hydrophobic character and the soakage angle of water drop is larger than 90 degrees. The windows have fog-proof ability owing to eliminate the capillary phenomena in the inner surface. The physics and chemical properties of the coated windows are steady. Study indicates that the performance of a-C:H coated mobile phone windows are improved notably on wear-resistance, corrosion-proof and optical properties and it is excellent mobile windows protective coatings.

• 대한한의학회지
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• 제25권1호
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• pp.117-128
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• 2004

Objectives : This research was performed to investigate effect of Samul-tang-gamibang against focal cerebral ischemic damage after middle cerebral artery occlusion(MCAO). Methods : This research was used rats which were against focal cerebral ischemic damage by MCAO. It was used Zea Longa's theory and Belayev's methods to give rise to focal cerebral ischemic damage by MCAO. After 7days later, we drew out the brain and then had frozen and dyeing it and we had taken a picture to measure of the damaged area in each brain section. We determined the Neurological Index and tested the Foot-fault test and Roatated test to appraise the fall of motion ability result from cerebral ischemic damage. Results : The results of the experiment are as follows. 1. Samul-tang-gamibang reduced infarct size of sample group compared to control group at 7 day after MCAO. 2. Samul-tang-gamibang reduced infarct volume of sample group compared to control group at 7 day after MCAO. 3. Samul-tang-gamibang reduced foot-fault index of sample group compared to control group at 5,7 day after MCAO. Conclusions : Samul-tang-gamibang has protective effects against ischemic brain damage and had significant reduced infarct size and infarct volume of Rt-MCAO.

• 한국식품영양학회지
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• 제21권2호
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• pp.121-126
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• 2008

In a previous study, a mulberry fruit extract(MFE) supplement exhibited anti-inflammatory activity and improved serum lipid profiles in arthritic rats. The objective of this study was to determine whether dietary MFE could ameliorate inflammatory parameters and serum lipid levels in humans. Twenty-six middle-aged subjects(mean body mass index=27 $kg/m^2$) consumed MFE(100 $m{\ell}/day)$ after lunch for 4 wks. Anthropometric measurements, serum oxidative stress markers and serum lipid profile analyses were performed at baseline and then at 4 wk following the study. There were no significant differences in anthropometric measurements, including BMI, WHR, and body fat composition. After the 4 wk-intervention, serum levels of C-reactive protein(CRP), ferric-reducing ability of plasma(FRAP), serum triglyceride(TG) and LDL-cholesterol had significantly decreased(p<0.05), whereas serum levels of HDL-cholesterol significantly(p<0.05) increased. These findings suggest the consumption of mulberry extract may be protective against inflammation and the atherosclerotic state in elderly obese men at high risk for cardiovascular disease(CVD).

• 한국식품영양과학회지
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• 제42권11호
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• pp.1744-1752
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• 2013

본 연구에서 적색의 색소 성분을 함유한 오디 및 자초 추출물의 피부 광노화 보호효과를 조사하였다. 오디 추출물의 총 안토시아닌 함량을 분석한 결과 4.92 mg/g이었고 HPLC 분석을 통한 자초 추출물의 shikonin 함량은 9.58 mg/g으로 나타났다. 오디 및 자초추출물의 전자공여능은 각각 84.32%와 57.46%로 분석되어 오디가 우수하였으며, superoxide radical 소거능은 오디 추출물이 76.34%로 자초추출물 61.55%보다 항산화 활성이 높았다. 오디 및 자초추출물의 ORAC 값은 각각 $545.37{\mu}moles$ TE/g과 $427.18{\mu}moles$ TE/g으로 분석되어 오디 추출물의 항산화 활성이 높음을 알 수 있었다. HS68 세포에서의 UVB 조사군과 비교 시 MMP-1 생산 억제율은 오디 및 자초 추출물 $200{\mu}g/mL$ 첨가 시 각각 68.6%, 32.7%로 분석되었다. 무모쥐를 이용한 UVB 광노화 피부 동물 모델에서 오디 및 자초 추출물의 피부조직의 변화를 조사한 결과, 시료 처리군이 무처리군에 비해 홍반, 주름 두께 및 깊이, 표피 비후, 콜라겐 각질층, 표피층이 감소되었으며 수분함량은 증가하였다. 총 주름 깊이의 경우, 오디 추출물 7% 처리군과 자초 추출물 5% 처리군에서 대조군과 비교 시 30% 가량 억제되어 in vitro에서 뿐만 아니라 in vivo에서도 오디 및 자초 추출물이 UVB에 의한 피부 광노화 보호효과가 있음을 확인하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제5권4호
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• pp.333-342
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• 2001

Adriamycin is a commonly used chemotherapeutic agent for cancer, including acute leukemia, lymphoma, and a number of solid human tumors. However, recent studies have recognized severe cardiotoxicity after an acute dose, which are likely the result of generation of free radicals and lipid peroxidation. Therefore, the clinical uses of adriamycin have been limited. Melatonin, the pineal gland hormone known for its ability to modulate circardian rhythm, has recently been studied in its several functions, including cancer growth inhibition, stimulating the immune system, and acting as an antioxidant and radical scavenging effects. In the present study, we evaluated the effect of melatonin administration on adriamycin-induced cardiotoxicity in rat. Heart slices were prepared using a Stadie-Riggs microtome for the measurement of malondialdehyde (MDA) content used as an index of lipid peroxidation and lactate dehydrogenase (LDH) release as an indicator of lethal cell injury. Serious adriamycin-induced lethality was observed in rat by a single intraperitoneal injection in a dose-dependent manner. A single injection of adriamycin (25 mg/kg, i.p.) induced a lethality rate of 86%, with melatonin (10 mg/kg s.c. for 6 days) treatment reducing the adriamycin-induced lethality rate to 20%. The severe body weight loss caused by adriamycin was also significantly attenuated by melatonin treatment. Treatment of melatonin marked reduced adriamycin-induced the levels of MDA formation and LDH release. A cell damage indicated by the loss of myofibrils, swelling of the mitochondria as well as cytoplasmic vacuolization was seen in adriamycin-treated group. Melatonin attenuated the adriamycin-induced structural alterations. These data provide evidence that melatonin prevents adriamycin-induced cardiotoxicity and might serve as a combination with adriamycin to limit free radical-mediated cardiotoxicity.

• Asian-Australasian Journal of Animal Sciences
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• 제31권9호
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• pp.1420-1430
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• 2018

Objective: Epigallocatechin-3-gallate (EGCG) is a major ingredient of catechin polyphenols and is considered one of the most promising bioactive compounds in green tea because of its strong antioxidant properties. However, the protective role of EGCG in bovine oocyte in vitro maturation (IVM) has not been investigated. Therefore, we aimed to study the effects of EGCG on IVM of bovine oocytes. Methods: Bovine oocytes were treated with different concentrations of EGCG (0, 25, 50, 100, and $200{\mu}M$), and the nuclear and cytoplasmic maturation, cumulus cell expansion, intracellular reactive oxygen species (ROS) levels, total antioxidant capacity, the early apoptosis and the developmental competence of in vitro fertilized embryos were measured. The mRNA abundances of antioxidant genes (nuclear factor erythriod-2 related factor 2 [NRF2], superoxide dismutase 1 [SOD1], catalase [CAT], and glutathione peroxidase 4 [GPX4]) in matured bovine oocytes were also quantified. Results: Nuclear maturation which is characterized by first polar body extrusion, and cytoplasmic maturation characterized by peripheral and cortical distribution of cortical granules and homogeneous mitochondrial distribution were significantly improved in the $50{\mu}M$ EGCG-treated group compared with the control group. Adding $50{\mu}M$ EGCG to the maturation medium significantly increased the cumulus cell expansion index and upregulated the mRNA levels of cumulus cell expansion-related genes (hyaluronan synthase 2, tumor necrosis factor alpha induced protein 6, pentraxin 3, and prostaglandin 2). Both the intracellular ROS level and the early apoptotic rate of matured oocytes were significantly decreased in the $50{\mu}M$ EGCG group, and the total antioxidant ability was markedly enhanced. Additionally, both the cleavage and blastocyst rates were significantly higher in the $50{\mu}M$ EGCG-treated oocytes after in vitro fertilization than in the control oocytes. The mRNA abundance of NRF2, SOD1, CAT, and GPX4 were significantly increased in the $50{\mu}M$ EGCG-treated oocytes. Conclusion: In conclusion, $50{\mu}M$ EGCG can improve the bovine oocyte maturation, and the protective role of EGCG may be correlated with its antioxidative property.