• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1029-1035
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• 2014

The protolytic dissociation process of hydrochloric acid (HCl) and hydrofluoric acid (HF) is studied using the B3LYP and MP2 methods with the 6-311+G(d,p) basis set in the gas phase and in aqueous solution. To study the phenomena in detail, discrete and discrete/continuum models were applied by placing water molecules in various positions around the acid. The dissociation process was studied using the thermodynamic cycle involving the structures optimized both in the gas phase and in aqueous solution and was analyzed with two key energy factors, relaxation free energy (${\Delta}G_{Rex(g)}$) and solvation free energy (${\Delta}G_s$). Based on the results, we could understand the dissociation mechanism and wish to propose the best way to study acid dissociation process using the CPCM methodology in aqueous solution.

• Journal of IKEEE
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• v.23 no.2
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• pp.557-570
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• 2019

In this study, a novel hierarchical approach is investigated to extract coronary vessel from X-ray angiogram. First, we propose to combine Decimation-free Directional Filter Bank (DDFB) and Homographic Filtering (HF) in order to enhance X-ray coronary angiographic image for segmentation purposes. Because the blood vessel ensures that blood flows in only one direction on vessel branch, the DDFB filter is suitable to be used to enhance the vessels at different orientations and radius. In the combination with HF filter, our method can simultaneously normalize the brightness across the image and increases contrast. Next, a coarse-to-fine strategy for iterative segmentation based on Otsu algorithm is applied to extract the main coronary vessels in different sizes. Furthermore, we also propose a new approach to segment very small vessels. Specifically, based on information of the main extracted vessels, we introduce a new method to extract junctions on the vascular tree and level of nodes on the tree. Then, the window based segmentation is applied to locate and extract the small vessels. Experimental results on our coronary X-ray angiography dataset demonstrate that the proposed approach can outperform standard method and attain the accuracy of 71.34%.

• Progress in Superconductivity and Cryogenics
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• v.8 no.4
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• pp.12-14
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• 2006

YBCO coated conductors have been fabricated by the reel-to-reel processing using TFA-MOD method. In this work, the fluorine-free Y & Cu precursor solution was synthesized to shorten the calcining time by reducing the evolution of HF gas, thus the meter-long YBCO precursor films can be made within few hours by the continuous slot-die coating & calcination step using the F-free Y & Cu precursor solution. The annealing step was followed to make the YBCO films by the reel-to-reel method with the vertical gas flow system onto the moving tape. To increase the growth rate of the YBCO films by enhancing the removal of HF gas, the low total pressure was adopted in the annealing processing. And the water partial pressure and the oxygen partial pressure were varied to optimize the growth conditions of the MOD-YBCO films on the buffered metal tape. FE-SEM and XRD were used to investigate the surface morphologies and the texture of the meter-long YBCO films. The end-to-end critical current $(I_c)$ of 63A/cm-width and the critical current density $(J_c)$of $0.9MA/cm^2$ with the thickness of $0.7{\mu}m$ were obtained in the 0.42m long coated conductor.

• Nutritional Sciences
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• v.8 no.3
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• pp.181-188
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• 2005

We investigated the effects of diet manipulation on pro- and macro-glycogen accumulation and mobilization during exercise in different kinds of muscle fiber and tissue. Thirty-two Sprague-Dawley rats were divided into groups representing one of two dietary conditions: high fat (HF, n=16) or standard chow (CHOW, n=16). Each dietary group was fm1her divided into control (REST, n=8) and exercise (EXE, n=8). After an eight-week dietary intervention period, the animals in EXE swam for 3 hours while the animals in REST remained at rest Skeletal muscle (soleus, red gastrocnemius and white gastrocnemius) and liver samples were then dissected out and used for analyses. 1here was no statistical difference in body weight between the animals in the HF and mow groups (p>.05). Three hours of exercise significantly increased plasma free fatty acid (FFA) concentration in the animals in the CHOW group but not in the animals in the HF group. Both citrate. synthase (CS) and $\beta$-hydroxyacyl dehydrogenase ($\beta$-HAD) activities in skeletal muscles were higher in the HF group than in the mow group. CS and $\beta$-HAD activities were also the highest in red gastrocnemius and the lowest in white gastrocnemius. At both time points (i.e., rest and immediately after exercise) intramuscular triglyceride (IMTG) and liver TG concentrations were significantly higher in the HF compared to the CHOW. IMTG and liver TG changed selectively in the CHOW. Except in white gastrocnemius muscle, there was no significant difference in total glycogen content between HF and mow at rest. Although exercise significantly lowered total glycogen content in all groups and tissues (p<.05), the degree of reduction was markedly greater in the mow than in the HF. Whereas changes in proglycogen concentration showed a trend similar to those of total glycogen, alterations in macroglycogen concentrations clearly differed from those of total glycogen. Specifically, the degree of reduction of macroglycogen following three hours of exercise was substantially greater in the CHOW than in the HF. These results suggest that metabolic alterations induced by a long-term high fat diet may be caused by macro-glycogen rather than pro-glycogen.

• Korean Journal of Plant Resources
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• v.27 no.6
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• pp.642-649
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• 2014

The antioxidant potentials of the methanol extract and its various fractions from Agrimonia pilosa Ledeb were measured as 1,1-diphenyl-2-picrylhydrazyl (DPPH), and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging abilities as well as the reducing power decreasing NO in vitro. The methanol extract of Agrimonia pilosa Ledeb showed significantly strong scavenging effects on free radicals of DPPH, ABTS, and NO. Hexane fraction (HF), ethyl acetate fraction (EF) and n-butyl alcohol fraction (BF) were prepared by solvent fractionation. By comparison of polyphenol contents among BF and HF, EF with high polyphenol contents showed the highest DPPH, ABTS, and NO scavenging effects with the value of 50.2%, 80.4%, and 65.7%, respectively, at the highest tested dose. HPLC analysis revealed the presence of various phenolic compounds in EF of Agrimonia pilosa Ledeb. These results suggest that EF could be considered as natural antioxidant sources and dietary nutritional supplements to prevent oxidation-related diseases.

• Journal of Nutrition and Health
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• v.38 no.10
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• pp.817-826
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• 2005

Recently it has been reported that vitamin A and retinol binding proteins (RBPs) in blood and urine were changed in the condition of diabetes mellitus or hyperlipidemia. Fruits and vegetables are recommended to consume for the people suffered from these chronic degenerative diseases. The main components of fruits and vegetables are dietary fibers, for example cellulose and pectin, of which function to affect the absorption and excretion of dietary fat and fat-soluble substances. This study was conducted to investigate the effect of dietary fibers on RBPs mRNA expression in liver, small intestine and serum of rat fed high fat diet during 4 weeks. Sprague-Dawley rats, weighing 121g on average, were divided into four groups; (Control; $17\%$ fat & cellulose supplement diet, HF0: $25\%$ fat & fiber free diet, B:.Uc: $25\%$ fat & cellulose supplement diet and HF0: $25\%$ fat & pectin supplement diet) . The rats fed high fat diet groups (HF0, HFC, HFP) tended to consume the food less than the control group, but FER of HF0 groups was significantly higher than the control (p < 0.05) . The weight of adrenal gland in high fat diet groups (HF0, HFC, HFP) was significantly less than the control. Total lipid in feces daily excreted and in liver did not show any significant differences among the groups. Total cholesterol in HFP group was significantly different from that of HFC group. Serum total cholesterol and triglyceride in other group tended to lower than other groups and HDL cholesterol higher. Consequently, AI (atherogenic index) was the lowest in HFP group. Vit A contents in feces daily excreted tended to lower in high fat diet groups (HF0, HFP) compared to the control group. That content in adrenal gland was the lowest in HF0 group, but not in liver. In HFP group were down-regulated cRBPI mRNA in liver and cRBPII mRNA in small intestine and up-regulated RBP and transthyretin expression in serum compared to the other groups. In conclusion, dietary fibers, especially pectin, in high fat diet might down-regulate the expression of CRBP I, CRBP II mRNA in liver and small intestine, but increase the secretion of RBP into serum and therefore inhance the bioavailability of Vit A through the body. (Korean J Nutrition 38(10): 817$\sim$826,2005)

• Journal of Food Hygiene and Safety
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• v.34 no.4
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• pp.388-395
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• 2019

The object of the present study was to examine the effect of selenium-treated Spinacia oleracea L. on antioxidative defense system and oxidative damage in rats fed high-fat and high-cholesterol diets. Experimental rats were divided into six groups which were composed of normal diet group (N), high-fat and high-cholesterol diet group (HF), high-fat and high-cholesterol diet with 5% or 10% non-treated spinach supplemented group (SPA or SPB) and high-fat and high-cholesterol diet with 5% or 10% selenium-treated spinach-supplemented group (SSA or SSB). In the antioxidant enzyme activities of hepatic glutathione peroxidase and superoxide dismutase, activities increased in supplementation of non-treated or selenium-treated spinach groups compared to HF group. However, there was no significant difference in the activity of hepatic catalase among all experimental groups. The microsomal superoxide radical content of the SSB group was significantly reduced compared to the HF group. The mitochondrial carbonyl values of the SSB group were significantly reduced compared to the HF group. Thiobarbituric acid reaction substance (TBARS) values in RBC and liver were also reduced in non-treated or selenium-treated spinach-supplemented groups compared to the HF group. The hepatic TBARS values of the supplementation of selenium-treated spinach groups significantly decreased compared to the supplementation of non-treated spinach groups. These results suggest that selenium-treated spinach may reduce oxidative damage by the activation of antioxidative defense system in rats fed high-fat and high-cholesterol diets.

• Journal of Life Science
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• v.31 no.5
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• pp.488-495
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• 2021

The aim of this study was to investigate the possible antioxidant effect of Spirodela polyrhiza (SP) on rats fed a high fat and high cholesterol diet supplemented with either 5% (SPA group) or 10% (SPB group) SP for 4 weeks. The hepatic SOD activity of the HF group significantly decreased compared to that of the N group, but that of the SPA and SPB groups significantly increased. The GPx activity of the SPA and SPB groups in the liver was significantly greater than that of the HF group, and the hepatic catalase activity of the SPA and SPB groups significantly increased compared to the HF group. The hepatic superoxide radical content of the mitochondria and microsomes of the HF group significantly increased compared to that of the N group, but the contents were reduced in the group that took SP powder. The hepatic hydrogen peroxide content in the cytosol and mitochondria of the SP powder group was lower than in the HF group. The carbonyl content in the mitochondria and microsomes of the SPA and SPB groups was significantly lower than in the HF group. The TBARS values in the liver significantly decreased in the SPA and SPB groups. Spirodela polyrhiza was thus effective in reducing oxidative stress by regulating the hepatic antioxidant enzymes and the free radicals in rats fed high fat and high cholesterol diets.

• Nutrition Research and Practice
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• v.10 no.5
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• pp.501-506
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• 2016

BACKGROUNG/OBJECTIVES: Corn silk (CS) extract contains large amounts of maysin, which is a major flavonoid in CS. However, studies regarding the effect of CS extract on cholesterol metabolism is limited. Therefore, the purpose of this study was to determine the effect of CS extract on cholesterol metabolism in C57BL/6J mouse fed high-fat diets. MATERIALS/METHODS: Normal-fat group fed 7% fat diet, high-fat (HF) group fed 25% fat diet, and high-fat with corn silk (HFCS) group were orally administered CS extract (100 mg/kg body weight) daily. Serum and hepatic levels of total lipids, triglycerides, and total cholesterol as well as serum free fatty acid, glucose, and insulin levels were determined. The mRNA expression levels of acyl-CoA: cholesterol acyltransferase (ACAT), cholesterol 7-alpha hydroxylase (CYP7A1), farnesoid X receptor (FXR), lecithin cholesterol acyltransferase (LCAT), low-density lipoprotein receptor, 3-hyroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), adiponectin, leptin, and tumor necrosis factor ${\alpha}$ were determined. RESULTS: Oral administration of CS extract with HF improved serum glucose and insulin levels as well as attenuated HF-induced fatty liver. CS extracts significantly elevated mRNA expression levels of adipocytokines and reduced mRNA expression levels of HMG-CoA reductase, ACAT, and FXR. The mRNA expression levels of CYP7A1 and LCAT between the HF group and HFCS group were not statistically different. CONCLUSIONS: CS extract supplementation with a high-fat diet improves levels of adipocytokine secretion and glucose homeostasis. CS extract is also effective in decreasing the regulatory pool of hepatic cholesterol, in line with decreased blood and hepatic levels of cholesterol though modulation of mRNA expression levels of HMG-CoA reductase, ACAT, and FXR.

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.499-505
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• 2021

In this study, HRV signals are analyzed to compare the autonomic nervous system activity of non-pregnant women and pregnant women. 99 disease-free pregnant women and 27 non-pregnant women from W Hospital participated in the study. The acquired HRV signals were used by the program to perform time domain analysis and frequency domain analysis. The measured values were statistically analyzed for differences between pregnancy periods through a one-way ANOVA. In the results, SDNN and RMSSD in time domain analysis had significantly higher results in early pregnancy and non-pregnant women compared to mid- and late pregnancy. In frequency domain analysis, LF and HF had significantly higher values for pregnancy and non-pregnancy compared to midand late-term, but there was no significant difference between VLF and LF/HF. his means that as pregnancy progresses, the ability to control autonomous nerves decreases in the middle and late stages of pregnancy and increases physical fatigue and mental fatigue. Therefore, the longer the pregnancy period, the more special care is needed to maintain mental and physical stability of pregnant women.