• Nutritional Sciences
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• v.8 no.1
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• pp.10-15
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• 2005

An increase in serum cholesterol is directly associated with high incidences of cardiovascular diseases (CVD) and atherosclerosis. Serum lipid profiles are highly dependent on dietary fatty acids and age. The purpose of this study was to examine the age-related effects of polyunsaturated/saturated fatty acid ratios and antioxidant supplementation under the control of the dietary peroxidizability index (PI) value on serum lipid profiles in rats. While the PI level of dietary fatty acids was controlled at 81.22, the P/S ratios of fatty acids were 0.38 and 4.81 (LP and HP). The diets were supplemented with a vitamin E 1000 mg/kg diet and a selenium 2.5 mg/kg diet (LPS and HPS). Female Sprague-Dawley rats ages 3 weeks (young) and 16 weeks (adult) were fed four different experimental diets for 4 weeks. The serum triglyceride concentration of LPS was significantly higher in young rats than in adult rats. The total-cholesterol concentration of LP and HPS were higher in young rats than in adult rats. The high-density lipoprotein-cholesterol (HDL-C) concentration of LP, LPS and HP was higher in adult rats than in young rats. The low-density lipoprotein-cholesterol (LDL-C) concentration was higher in young rats than in adult rats. T-C/HDL-C and LDL-C/HDL-C ratios were much higher in young rats than in adult rats. In conclusion, P/S ratios and antioxidant supplementation did not affect T-C/HDL-C and LDL-C/HDL-C ratios as risk factors of CVD in adult rats when we controlled the PI value in the diet Probably, the invisible and confounding effects of dietary PI value implicate the beneficial roles of dietary P/S ratios and antioxidants in CVD. Accordingly, controlling the dietary PI value may be advantageous to lower the risk of CVD in adult rats.

• Journal of Mechanical Science and Technology
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• v.16 no.6
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• pp.861-869
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• 2002

Radiative transfer by nongray gas mixtures with nonuniform concentration and temperature profiles is studied by using the statistical narrow-band model and the ray-tracing method with the sufficiently accurate T$\_$60/ quadrature set. Transmittances through the nonhomogeneous gas mixtures are calculated by using the Curtis-Godson approximation. Three different cases with different temperature and concentration profiles are considered profiles are considered to obtain benchmark solutions for the radiative transfer by nongray gas mixtures. The solutions obtained from this study are verified and found to be very well matched with the previous solutions for uniform gas mixtures. The results presented in this paper can be used as benchmark solutions in developing various solution methods for radiative transfer by nongray gas mixtures.

• Analytical Science and Technology
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• v.8 no.4
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• pp.707-714
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• 1995

Two types of regularization method (singular system and HMP approaches) for generating depth-concentration profiles from angle-resolved XPS data were evaluated. Both approaches showed qualitatively similar results although they employed different numerical algorithms. The application of the regularization method to simulated data demonstrates its excellent utility for the complex depth profile system. It includes the stable restoration of the depth-concentration profiles from the data with considerable random error and the self choice of smoothing parameter that is imperative for the successful application of the regularization method. The self choice of smoothing parameter is based on generalized cross-validation method which lets the data themselves choose the optimal value of the parameter.

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.237-241
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• 1990

A detailed theoretical and experimental study of k-na exchange in soda lime silicate glasses by RTP is presented. Concentration profiles i.e. index profiles are given by complementary error function added Gaussian function. The estimated diffusion coefficient is 1.54${\mu}{\textrm}{m}$2/min.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.197-201
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• 1997

The momentum, heat and mass trasfer phenomena in the silicon melt of the Czochralki crystal growth system are calculated using a three dimensional numerical simulation thechnique. Even though axisymmetrical boundary conditions are imposed to all calculations in a 3cm diameter crucible, several types of non-axisymmetric profiles of velocities, temperature and oxygen concentration appeared in the melt. Because of the non-axisymmetric profiles of velocities, temperature and oxygen concentration appeared in the melt. Because of the non-axisymmetric profiles and rotations of fluid induced by the crucible rotation, temperatures and oxygen concentrations in the silicon melt fluctuate. The rotating velocity of the profile is calculated from the phase shift of the data of temperature or oxygen at two different points which have same radius from center but 90 degree angular difference. From this calculation, it is found that the rotating veolocity of the oxygen and temperature is different from the crucible rotation rates. Therefore the frequencies of the oscillating temperature and oxygen concentrations are not same to the frequencies of the crucible rotations. Futhermore, the components of the frequencies of the temperature and oxygen concentration at the same point are not same. The fluctuation behaviors of the temperature or oxygen themselves are also different when the points are different. The calculation show that the temperature and the oxygen concentration near the interface also fluctuate. The results suggest that the striation pattern found in the grown silicon single crystals may ben generated by the oxygen concentration and the temperature oscillations of the melt occurred near the interface.

• Biomaterials and Biomechanics in Bioengineering
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• v.1 no.1
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• pp.13-25
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• 2014

In the current study, a drug-eluting stent coated with biodegradable polymers and sirolimus was developed by using an ultrasonic nanocoater and characterized in aspects of surface smoothness and coating thickness. In addition, in vitro release profiles of sirolimus by changing top coating layer with different biodegradable polymers were investigated. Smooth surfaces with variable thickness could be fabricated by optimizing polymer concentration, flow rate, nozzle-tip distance, gas pressure, various solvents and ultrasonic power. Smooth surface could be generated by using volatile solvents (acetone, chloroform, and methylene chloride) or post-treating with solvent vapor. Coating thickness could be controlled by varying injection volume or polymer concentration, and higher concentration could reduce the coating time while obtaining the same thickness. The thickness measurement was the most effectively performed by a conventional cutting method among three different methods that were investigated in this study. Release profiles of sirolimus were effectively controlled by changing polymers for top layer. PLGA made the release rate 3 times faster than PDLLA and PLLA and all top layers prevented burst release at the initial phase of profiles. Our results will provide useful and informative knowledge for developing drug-eluting stents, especially coated with biodegradable polymers.

• Nutrition Research and Practice
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• v.1 no.4
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• pp.291-297
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• 2007

This study was conducted to investigate the effect of dietary soluble fiber administration and/or high fat diet on serum and brain neurohormonal profiles, adipose tissue mass and body weight gain in Sprague-Dawley rats. Four groups of rats were respectively fed 10% fat diet (C), 10% fat plus pectin diet (P), 20% fat diet (HFC) and 20% fat plus pectin diet (HFP) for 4 weeks. In HFP group, the food and energy intake, body weight gain, FER including fecal excretion were the smallest (p<0.05). Serum HDL-cholesterol, triglyceride and glucose level were also the lowest in HFP group (p<0.05). The weight of brain, epididymal fat pad and adrenal gland except liver didn't show any significant differences among groups. Interestingly serum norepinephrine concentration of HFP group tended to be higher, but dopamine concentration tended to be lower than those of HFC group. However serum catecholamine concentration didn't show any significant differences among all groups. Norepinephrine and epinephrine contents of right portion of midbrain of P and HFP groups were remarkably lower than those of the C group. These results suggested that soluble fiber pectin consumption might affect neurohormonal profiles in serum and brain according to dietary fat level.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2004.11a
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• pp.73-79
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• 2004

The large-scale preparation method for black soybean peptide (BSP; about 70% less than 10,000 Da; highly enriched with glutamic acid, aspartic acid, and arginine) was developed, and its effect on weight reduction and lipid profiles in rats was investigated. Sprague-Dawleymale rats were assigned to four dietary groups (high-fat diets containing 0, 2, 6, and 10% BSP) and fed four weeks to examine the effects of BSP. During the experiment, food intake was measured every two days and body weight was monitored two times a week. After the supplementation of BSP, liver and adipose tissues (epididymal, retroperitoneal and perirenal adipose tissue) in the rats were weighted and the lipid profiles in serum, liver, and feces were analyzed. At the results of body weight gain, liver and epididymal adipose tissue weight, BSP groups were more decreased than HF group (0% BSP), with greater decreases at higher BSP levels. The same patterns were shown in lipid profiles of serum, as BSP was increased, triglyceride and total cholesterol concentration decreased. The serum HDL-cholesterol level was increased with increasing at BSP levels. Total cholesterol concentration of liver and feces were decreased and increased, respectively, as BSP increased. The results confirm that BSP is involved in reducing the body weight and the improvement of lipid composition in serum and liver of rats and that BSP can be applied in weight reduction in the food products industry.

• Journal of Nutrition and Health
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• v.35 no.8
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• pp.854-862
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• 2002

In the present study, we investigated the effects of chronic green tea consumption on the serum lipid profiles of 92 subjects (mean age: 59.5 $\pm$ 8.9, men: 41, women:51) living in a green tea cultivation village. The anthropometric and biochemical blood indices were measured, and nutritional intakes were assessed using 24-h recall method. Also, we administered a questionnaire regarding green tea consumption. The subjects were divided into three groups based on the period of green tea consumption (0, < 10 year, and $\geq$ 10 year). There were no significant differences in age, anthropometric indices (Wt, Ht, BMI, Body fat, LBM), and nutritional intakes among the groups. Serum LDL-cholesterol concentration was significantly lower in the $\geq$ 10 year group compared with the other groups (p < 0.05). Also, the LDL/HDL-cholesterol ratio was significantly lower in the $\geq$ 10 year group compared with the other groups (p < 0.05). The frequency of subjects with a normal range of serum LDL-cholesterol concentration (< 200 mg/dl) was significantly higher in the $\geq$ 10 year group compared with the other groups (p < 0.05). These results imply positive effects of chronic green tea consumption on blood lipid profiles, which requires confirmation in further studies.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.3
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• pp.46-55
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• 1998

This stud demonstrates the profiles of heavy ions (As, Sb) in silicon by high energy (1~10 MeV) implantation. Implanted profiles were measured by SIMS (Cameca 4f) and compared with simulation results (TRIM) program and analytical description method using Pearson function). The experimental results have a little bit deviation with simulation data in the case of As high energy implatation. But in the case of Sb, the experimental results are in good agreement with TRIM data. SIMS profiles are perfectly fitted with a analytical description method only using one pearson function in Sb implantation. but in the case of As, fitted profilesshow with a little bit deviations by channeling effects of SIMS profiles. Thermal annealing for electrical activation of implanted ions was carried out by furnace annealing and RTA(Rapid Thermal Annealing). Concentration-depth profile after heat treatement were measured by SR(Spreading Resistance) method.