• 한국식품영양학회지
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• 제20권4호
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• pp.440-449
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• 2007

The purpose of this study was to examine the effects of taurine supplementation on serum lipidperoxide(TBARS), a risk factor for cardiovascular disease. The subjects were 22 healthy middle-aged women(33 to 54 years). Serum lipids, thiobarbituric acid reactive substances(TBARS), and plasma taurine levels were measured before and after supplying 3 g of taurine per day for 4 weeks. Plasma taurine was analyzed by Dabsyl-Cl(4-dimethylamino azobenzen-4-sulfonyl-chloride) derivatization and reversed-phase HPLC. Serum TBARS was measured by the Yagi method. Daily dietary taurine intake was calculated by food frequency questionnaire method. The weight and height means of the 22 subjects were $57.9{\pm}5.2$ kg and $159.2{\pm}5.2$ cm, respectively. Their percent body fat and waist/hip ratio(WHR) were 26.8% and 0.84, respectively, which were slightly higher than the average for middle-aged Korean women. Serum TC, TG and LDL-C levels tended to decrease after taurine supplementation, but HDL-C was not changed. A positive correlation between plasma taurine and HDL-C was shown after taurine supplementation. The serum TBARS concentration was significantly decreased from $5.05{\pm}0.84nmol/d{\ell}$ to $4.17{\pm}0.64nmol/d{\ell}$ after taking taurine(p<0.01), and the plasma taurine concentration was significantly increased from $63.7{\pm}14.2{\mu}mol/{\ell}$ to $73.8{\pm}16.6{\mu}mol/{\ell}$ after taurine supplementation(p<0.05). The average dietary intake of taurine was $178.5{\pm}50.4$ mg/day, which is similar to the average daily taurine intake of Korean women. In conclusion, taurine is an effective nutrient that antagonizes TBARS levels. Therefore, this study suggests that a sufficient taurine intake may be an effective way to prevent cardiovascular disease such as atherosclerosis.

• 대한지역사회영양학회지
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• 제7권6호
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• pp.844-851
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• 2002

Smoking can increase oxidative stress and thereby change the antioxidant defense system in the body. To investigate the relationship between male adolescent smoking and antioxidant status, we surveyed the eating habits and dietary intake of 82 smokers and 44 nonsmokers recruited from a male technical high school. In addition, antioxidant enzyme activity and lipid peroxide values were determined in both the plasma and the erythrocytes. Although the frequency of food intake was not significantly different, most nutrient intake was unexpectedly higher in smokers than in nonsmokers. In comparison with the Korean RDA, especially the average intake of Ca, Fe and vitamin $B_2$ didn t reach 75% of the Korean RDA in either smokers or nonsmokers. An analysis of antioxidant enzyme activity showed that plasma catalase. superoxide dismutase (SOD), glutathione peroxidase (GSH-px), erythrocyte catalase and GSH-px activities showed no significant difference between smokers and nonsmokers. However, the erythrocyte SOD activity of smokers (1.57 unit/mgHb) was significantly lower than that of nonsmokers (2.00 unit/mg Hb). In addition, the plasma ceruloplasmin concentration of smokers (28.68 mg/$d\ell$) was significantly higher than that of nonsmokers (26.30 mg/$d\ell$), whereas the specific ceruloplasmin ferroxidase activity of smokers (0.31 unit/mg) was lower than that of nonsmokers (0.35 unit/mg). The plasma and erythrocyte thlobarbituric acid reactive substance (TBARS) of smokers (2.57 $\mu$mol/L, 0.32 $\mu$mol/gHb) were also significantly higher than those of nonsmokers (2.25 $\mu$mol/L, 0.27 $\mu$mol/gHb). The overall data indicate that adolescent smoking might decrease the antioxidant capacity of the body, in part, by lowering the erythrocyte SOD activity and the specific ceruloplasmin ferroxidase activity.

• Preventive Nutrition and Food Science
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• 제9권1호
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• pp.79-84
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• 2004

Zinc intake and status of South Koreans from rural, urban and metropolitan areas were investigated. The dietary habits of 760 healthy male and female adult subjects with a mean age of 54 were assessed using a food frequency questionnaire and were verified using 24 h dietary recall. Daily Zn intakes for men and women were 7.4$\pm$5.4 mg and 7.0$\pm$5.4 mg, respectively, which were 62% and 70% of the Korean RDA. The phytate : zinc and phytate ${\times}$ calcium : zinc molar ratios were 38 and 398, respectively. Both the low intake of zinc and the high extremely phytate and phytate ${\times}$ calcium ratios with Zinc suggest that South Koreans may be at risk of zinc deficiency. Plasma zinc (86$\pm$61 $\mu\textrm{g}$/dL), urinary zinc (33$\pm$27 $\mu\textrm{g}$/dL) and plasma alkaline phosphatase (102$\pm$52 mU/mL) levels within the normal range did not however suggest marked Zinc deficiency in these subjects. However, conventional zinc biomarkers aye known to be unreliable for assessment of marginal zinc deficiency. Based on zinc intake alone, it is likely that at least a proportion of these subjects were marginally zinc deficient and the wider consumption of zinc rich, phytate deficient foods, particularly in rural areas, would be beneficial.

• 동굴
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• 제76호
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• pp.37-42
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• 2006

The Dielectric Barrier Discharge (DBD) is a nonequilibrium gas discharge that is generated in the space between two electrodes, which are separated by an insulating dielectric layer. The dielectric layer can be put on either of the two electrodes or be inserted in the space between two electrodes. If an AC or pulse high voltage is applied to the electrodes that is operated at applied frequency from 50Hz to several MHz and applied voltages from a few to a few tens of kilovolts rms, the breakdown can occur in working gas, resulting in large numbers of micro-discharges across the gap, the gas discharge is the so called DBD. Compared with most other means for nonequilibrium discharges, the main advantage of the DBD is that active species for chemical reaction can be produced at low temperature and atmospheric pressure without the vacuum set up, it also presents many unique physical and chemical process including light, heat, sound and electricity. This has led to a number of important applications such as ozone synthesizing, UV lamp house, CO2 lasers, et al. In recent years, due to its potential applications in plasma chemistry, semiconductor etching, pollution control, nanometer material and large area flat plasma display panels, DBD has received intensive attention from many researchers and is becoming a hot topic in the field of non-thermal plasma.

• Elastomers and Composites
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• 제36권2호
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• pp.94-101
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• 2001

본 연구에서는 RF-plasma를 사용하여 카본블랙을 $N_2$ 분위기에서 표면처리 하였을 때 카본블랙의 표면 산도 및 염기도와 이온 흡착 특성, 그리고 표면 자유에너지를 통한 물리-화학적변화를 관찰하였다. 그 결과 카본블랙을 플라즈마 표면처리 하였을 경우 표면 자유에너지의 비극성 요소 (${\gamma}s^L$)가 크게 증가함을 고찰하였다. 또한 표면 산도 및 표면 염기도와 이온 교환특성, 제타 전위, 그리고 이온 이동도의 향상 등에 의한 표면 관능기의 발달로 표면처리 시간이 증가됨에 따라 극성요소 (${\gamma}s^{sp}$)인 전자 받게 (${\gamma}s^+$)와 전자 주게 (${\gamma}s^-$) 인자도 증가하는 것을 볼 수 있었다.

• Journal of Community Nutrition
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• 제2권2호
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• pp.119-128
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• 2000

Lifestyle and dietary behavior intervention as the primary prevention of lipid disorder seems safe and compatible with other treatments of cardiovascular diseases. Cross-sectional associations between lifestyle factors and dietary behavioral factors with plasma lipid and lipoprotein levels were analyzed in 189 middle-aged men in Suwon, Korea. Overnight fasting plasma levels of total cholesterol, high-density lipoprotein(HDL)-cholesterol, triacylglycerol and glucose were analyzed. Blood pressure and anthropometric data were also measured. Lifestyle factors such as smoking status, alcohol consumption and frequency of physical exercise were evaluated by a self-administered questionnaire. Questions regarding dietary behavior were also asked. The subjects were 43.8%${\pm}$7.9 years old, and 23.8%${\pm}$2.6kg/m$^2$. From stepwise regression analyses, significant correlates with total cholesterol level were body mass index(BMI), alcohol intake(negative), age and coffee drinking(model R$^2$=14.3%). BMI, breakfast-skipping, age, and sleeping hours were significant for triacylglycerol level(model R$^2$=15.8%). BMI, alcohol drinking(negative), age, and coffee drinking were significant for low-density lipoprotein(LDL)(model R$^2$=11.7%). Age(negative), BMI(negative), alcohol drinking, stress level(negative), physical exercise, and cigarette smoking(negative) were significant for high-density lipoprotein(HDL)(model R$^2$=12.1%). From stepwise regression analyses, excluding BMI and age as factors in the model, alcohol intake(negative) and coffee drinking were significantly correlated with total cholesterol level(model R$^2$=4.4%) : breakfast-skipping with triacylglycerol(model R$^2$=3.2%) : alcohol intake (negative) with LDL level(model R$^2$=3.4%) : alcohol intake, physical exercise and stress level(negative) with HDL level(model R$^2$=6.3%). The findings suggest that a healthy daily lifestyle and dietary behavior may have an anti-atherogenic effect by altering plasma lipid and lipoprotein levels in middle-aged Korean men. (J Community Nutrition 2(2) : 119∼128, 2000)

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권5호
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• pp.319-325
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• 1999

Direct current(d.c.)leakage current voltage characteristics of radio-frequencymagnetron sputtered BaTa\sub 2\O\sub 6\ film capacitors with aluminum(A1) top and indium tin oxide (ITO) bottom electrodes have been investigatedas a function of applied field and temperature. In order to study surfacetreatment effect on the electrical characteristics of as-deposited film weperformed exposure of oxygen plasma on $BaTa_2O_6$ surface. d. c.current-voltage (I-V), bipolar pulse charge-voltage (Q-V), d. c. current-time (I-t) andcapacitance-frequency (C-f) analysis were performed on films. All ofthe films exhibita low leakage current, a high breakdown field strength (3MV/cm-4.5MV/cm), and high dielectric constant (20-30). From the temperature dependence of leakage current,we can conclude that the dominant conduction mechanism is ascribed toSchottky emission at high electric field (>1MV/cm) and hopping conduction at lowelectric field (<1MV/cm). According to our results, the oxide plasma surfacetreatmenton as-deposited $BaTa_2O_6$ resulted in lowering interfacebarrier height and thus, leakage current when a negative voltage applied to the A1 electrode. This can be explained by reduction of surface contamination via etching surface and filling defects such as oxygen vacancies.

• Biomolecules & Therapeutics
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• 제10권4호
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• pp.274-280
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• 2002

The fluoroquinolones have been reported to cause, although at low frequency, severe phototoxicity which is due to singlet oxygen produced by ultraviolet-A (UVA; 320-400 nm) exposure. The objective of this study was to evaluate the phototoxicity based on plasma and tissue concentrations of commonly prescribed fluoroquinolones; lomefloxacin (LFLX), enoxacin (ENX), ofloxacin (OFLX), and ciprofloxacin (CPFX). The phototoxic potentials were investigated by measuring increments in ear thickness, 24 hrs after these fluoroquinolones were orally administered to Balb/c mice, which they were exposed to UVA 17.5 J/$\textrm{cm}^2$ for 2 hrs following drug administration. The fifty percent ear thickness increment-inducing doses ($ETID_{50}$), determined by single ascending dosing of each fluoroquinolone to mice, were calculated to be 50(LMFX), 250(ENX), 770(OFLX), 1100(CPFX) mg/kg. Post the administration of ETID$_{50}$, drug concentrations in plasma and ear tissue were measured at specified times and phototoxicities were quantified. Both peak plasma ($\mu\textrm{g}$/ml) and ear tissue ($\mu\textrm{g}$/g) concentrations were summarized as follows; 7.3/1.4 for LMFX, 15.0/1.6 for ENX, 90.1/18.4 for OFLX and 87.2/3.7 for CPFX. The degree of photo toxicity was more relevant to plasma concentrations than tissue concentrations. In order to assess the effect of irradiation time after drug administration on phototoxicity, the 2 hr UVA irradiation was given at 0, 1, 2, 3, and 5 hr after administering $ETID_{50}$, respectively and photo toxicities were evaluated. The shorter inteval between dosing and UVA exposure was, the higher risk of phototoxicity was produced.d.

• 대한금속재료학회지
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• 제47권1호
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• pp.44-49
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• 2009

본 연구에서는 2인치 ITO의 타깃으로 ITO박막을 성장시킨 후 RTA 처리로 인한 전기적, 광학적 특성의 변화를 조사하였으며, RTA 처리된 ITO 박막을 이용하여 플라즈마 응용 사인보드를 제작 및 구동하였다. RTA공정으로 열처리한 ITO는 투과도는 증가하며, 비저항은 감소함을 관찰하였으며, 투과도의 증가는 RTA로 인한 결정성의 증가로 인한 결과이고, 비저항의 감소는 결정성의 증가와 더불어 치환형 주석의 원자수가 증가하였다고 사료된다. ITO를 이용하여 사인보드 제작시 방전cell의 압력은 3-5 Torr가 적당함을 알 수 있었으며, 전극 간격을 조절하여 120 V 정도의 낮은 플라즈마 개시 전압을 갖는 플라즈마 응용 사인보드를 성공적으로 제작 할 수 있었다.

• 반도체디스플레이기술학회지
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• 제20권4호
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• pp.72-77
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• 2021

The radial distribution of etch rate was analyzed using the ion energy flux model in VHF-CCP. In order to exclude the effects of polymer passivation and F radical depletion on the etching. The experiment was performed in Ar/SF6 plasma with an SF6 molar ratio of 80% of operating pressure 10 and 20 mTorr. The radial distribution of Ar/SF6 plasma was diagnosed with RF compensated Langmuir Probe(cLP) and Retarding Field Energy Analyzer(RFEA). The radial distribution of ion energy flux was calculated with Bohm current times the sheath voltage which is determined by the potential difference between the plasma space potential (measured by cLP) and the surface floating potential (by RFEA). To analyze the etch rate uniformity, Si coupon samples were etched under the same condition. The ion energy flux and the etch rate show a close correlation of more than 0.94 of R² value. It means that the etch rate distribution is explained by the ion energy flux.