• Polymer(Korea)
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• v.37 no.1
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• pp.61-65
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• 2013

In this work, the anodic oxidation of carbon fibers was carried out to enhance the mechanical interfacial properties of carbon fibers-reinforced epoxy matrix composites. The surface characteristics of the carbon fibers were studied by FTIR, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Also, the mechanical interfacial properties of the composites were studied with interlaminar shear strength (ILSS), critical stress intensity factor ($K_{IC}$), and critical strain energy release rate ($G_{IC}$). The anodic oxidation led to a significant change in the surface characteristics of the carbon fibers. The anodic oxidation of carbon fiber improved the mechanical interfacial properties, such as ILSS, $K_{IC}$, and $G_{IC}$ of the composites. The mechanical interfacial properties of the composites anodized at 20% sulfuric/nitric (3/1) were the highest values among the anodized carbon fibers. These results were attributed to the increase of the degree of adhesion at interfaces between the carbon fibers and the matrix resins in the composite systems.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1503-1510
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• 1999

This study was performed to investigate the physicochemical properties of Korean Citrus sudachi fruit which were harvested at different harvesting time(every 20 days from Sep. 3 to Nov. 8) and region(Seogwipo and Cheju city area). The average weight of Citrus sudachi fruit harvested from Seogwipo area was as twice as that of Cheju area at the same period. The moisture content in fruit peel increased by ripening of fruit, but that of fruit juice showed no difference. The content of reducing sugar in fruit peel and fruit juice increased 2 times from Sep. 3 to Nov. 8. The content of crude fiber decreased both in fruit peel and fruit juice as progression of ripening. Crude protein and ash contents decreased in fruit peel but revealed no differences in the fruit juice during the same period. pH decreased in fruit peel and juice with its ripening. The content of vitamin C decreased by ripening of fruit. The transmittance which is important quality factor in fruit juice increased from Sep. 20 to Oct. 13. The content of free sugar increased about 2 times in fruit peel from Sep. 3 to Nov. 8 and showed 4 times increase in fruit juice at the same period. In the composition ratio of mineral, Ca and K were abundant in the fruit peel, but only K was the most abundant mineral in fruit juice than any others.

• Korean Journal of Acupuncture
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• v.24 no.3
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• pp.179-204
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• 2007

Objectives & Methods : The purpose of this study is to observe the effects of Angelicae Radix Pharmacopuncture(AR-P) at Joksamni(ST36) on collagen II induced arthritis in DBA/1J mice. The authors evaluated arthritis index, arthritis incidence and joint edema, and measured body weight, spleen size and stenosis rate, serum cytokine level, serum antibody level, immune cell populations In spleen, lymph node, and knee joint, and performed histological analysis of CIA mouse joint. Results : In the AR-P group, arthritis index, arthritis incidence and joint edema were decreased, and the enlargement, malformation and stenosis of spleen and the malformation of joint appeared milder than the control group. In AR-P group, the levels of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, $IFN-{\gamma}$ in serum were significantly decreased. And the level of anti-collagen II in serum was maintained lower in AR-P group than in the control group. In AR-P group, the level of $IFN-{\gamma}$ and IL-10, and $IFN-{\gamma}/IL-4$ ratio were significantly decreased, and the ratios of $CD3e^+$ cells to $CD45^+$ cells, $CD4^+$ cells to $CD8^+$ cells in spleen were similarly maintained as those of the normal group. In the AR-P group, the populations of $CD4^+/CD25^+$ cells in spleen and lymph nodes, $CD45R^+/CD69^+$ cells in lymph nodes, $CD3^+/CD69^+$ cells and $CD11b^+/Gr-1^+$ cells in knee joint were decreased. In the histological analysis, the cartilage destruction, synovial cell proliferation and the collagen fiber destruction were decreased in the AR-P group Conclusions : The results suggest that AR-P at right ST36 has a therapeutic effect on collagen-induced arthritis in mice.

• Korean Journal of Community Nutrition
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• v.13 no.4
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• pp.476-488
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• 2008

This study investigates the relationship of smoking on daily intake of nutrients and snacks in the Chungnam and Daejeon high school students. Up to date scientific nutrition education and counseling programs in the regular school system is needed for a professional nutrition education teacher. The primary objective of this study was to provide useful information to nutrition education teachers. A survey was conducted with 400 high school students in the Chungnam and Daejeon areas. 381 out of 400 questionnaires were analyzed with SPSS 12.0K. The subjects were composed of 49.8% male, 50.1% female and 40.9% regular high school students, 59.1% business high school students and smokers 43.1%, non-smokers 56.9%. 43.4% of smokers had been smoking since middle school. On analysis of daily nutrient intakes, 16 out of 19 nutrients except animal calcium, Vitamin A and Vitamin C were much more consumed by the smoking group than the non-smoking group non-significantly. Especially vegetable fat and Vitamin E were higher in the smoking group than the non-smoking group (p<0.05). The intake ratio of carbohydrates: protein: fat was similar in the two groups (smoking group 55:15:29, nonsmoking group 56:15:28). Intakes of Vitamin B1 and potassium in comparison with the Korean dietary reference intakes(KDRI) were under 50% in both groups. However, sodium was taken over 200% compared to KDRI in both groups. Intakes of Vitamin C in the smoking group were as low as 76.5% in comparison to KDRI. Smokers need to increase the intakes of Vitamin C considering that smokers need to intake Vitamin C two times than non-smokers. Nutrient intakes from snacks in the smoking group were higher than the non-smoking group. Nutrients that originated from snacks which took over 20% among daily nutrient intakes were 12 nutrients(energy, fat, carbohydrate, calcium, P, Fe, K, Vitamin $B_1$, Vitamin $B_2$, Vitamin C, Vitamin E, dietary fiber) in the smoking group compared to 7 nutrients(energy, vegetable protein, fat, carbohydrate, calcium, Vitamin $B_2$, Vitamin C) in the non-smoking group. The smoking group was significantly paying more money for snacks each month than the non-smoking group was(p<0.01). Periods of consumption were irregular in the smoking group(p<0.05) and the smoking group was used to taking snacks in the morning compared to the non-smoking group. The smoking group preferred sweets and high calorie food over other snacks in comparison of the non-smoking group. The nonsmoking group had better eating habits than the smoking group.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4245-4252
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• 2015

In this study, an experiment which utilized glass fiber reinforced polymer(GFRP) plank as the permanent formwork of cast-in-place high strength concrete structures was performed. The GFRP plank currently being produced has smooth surface so that it causes problems in behavior with concrete. Therefore, this research analyzed the flexure/shear failure behavior of composite beams, which used GFRP plank as its permanent formwork and has short shear span ratio, by setting the sand coated at GFRP bottom surface, the perforation and interval of the GFRP plank web, and the width of the top flange as the experimental variables. As a result of the experiments for effectiveness of sand attachment in case of not perforated web, approximately 47% higher ultimate load value was obtained when the sand was coated than not coated case and bending/shear failure mode was observed. For effectiveness of perforation and interval of gap, approximately 24% higher maximum load value was seen when interval of the perforation gap was short and the fine aggregate was not coated, and approximately 25% lower value was observed when the perforation gap was not dense on the coated specimen. For effectiveness of top flange breadth, the ultimate load value was approximately 17% higher in case of 40mm than 20mm width.

• Journal of Nutrition and Health
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• v.32 no.5
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• pp.540-551
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• 1999

This study was performed to investigate the effects of dried leaf powders and ethanol extracts of Perilla frutescens(perilla leaf), Artemisia princeps var. orientalis(mugwort) and Aster scaber(chamchui) on lipid metabolism and antioxidative capacity in rats. Forty-nine male Sprague-Dawley rats weighing 105.9$\pm$1.7g were blocked into seven groups according to body weigth and raised for four weeks with diets containing 5% dried powders of perilla leaf, mugwort and chamchui, or ethanol extracts from the same amount of each dried leaf powder. Food intake was higher in the control and chamchui powder groups than the other remaining groups. Weight gain was not significantly different among all experimental groups. Food efficiency ratio was highest in the perilla leaf powder group. Plasma total lipid and cholesterol, liver total lipid and triglyceride levels were highest in the perilla leaf powder group. In contrast, dried powders of mugwort and chamchui showed hypolipidemic effects in plasma and liver. Plasma and liver TBARS levels in both dried powder and ethanol extract groups of the three plants were lower than control. There was also no significant difference between corresponding dried powder and ethanol extract groups. Catalas and GSH-Px activities in erythrocyte and liver were not different among all the experimental groups. However, SOD activities were significantly different among the esperimental groups. In erythrocyte. SOD activiteis of all dried powder and ethanol extract groups except the perilla leaf powder group were higher than control, and the chamchui power group showed the highest activity among them. In liver, all the plant groups showed higher SOD activities than control. There was no significant difference between corresponding dried powder and ethanol extract groups. In conclusion, the dried chamchui powder and liver. All the dried plant powder and ethanol extract were effective in decreasing the TBARS levels of liver and particularly plasma. Among the antiocidative enzymes, SOD activity was most responsive to the experimental diets. All the plant groups showed increases in liver SOD activities and there were more increments in dried powder groups. Since the effects of dried powder groups on lipid metabolism were better than those of extract groups, it is plausible that the high dietary fiber level in dried powders was effective. Antioxidative effects were not significantly different between corresponding dried power and extract groups, and it was thought that ethanol extracts from three plants also had similar antioxidative effects as dried powderers.

• Journal of Nutrition and Health
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• v.50 no.3
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• pp.257-269
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• 2017

Purpose: This study was conducted to evaluate the risk of metabolic factors in adults consuming 3-in-1 coffee from the 2012~2015 Korea National Health and Nutrition Examination Survey (KNHANES). Methods: A total of 5,872 subjects (male = 2,253, female = 3,619) aged 19~64 yrs were presented with food frequency questionnaires, and they were classified according to coffee consumption level and types of coffee consumed (black coffee, ${\leq}1$ time/day of 3-in-1 coffee, > 1 and ${\leq}2$ times/day of 3-in-1 coffee, > 2 times/day of 3-in-1 coffee). Analysis was conducted by gender for age-stratified groups: 19~39 (male = 968 and female = 1,285) and 40~64 (male = 1,468, female = 2,151) yrs old. Results: Black coffee consumption was associated with a significantly higher education level and household income compared to 3-in-1 coffee consumption in both males and females. The > 2 times/day group had significantly more smokers compared to other patterns of coffee consumption in both males and females. In the 40~64 yrs age group, males and females in the > 2 times/day group had significantly lower density of micronutrients such as fiber, niacin, vitamin C, calcium, phosphorus, and potassium compared with black coffee consumption. In the 40~64 yrs age group, males (OR: 2.03, 95% CI: 1.13~3.64) in the > 2 times/day group were at a higher risk of metabolic syndrome compared with black coffee consumption after multivariable adjustment. Conclusion: We found that frequency of 3-in-1 coffee consumption may be associated with prevalence of metabolic syndrome in males aged 40~64 yrs.

• Journal of Sericultural and Entomological Science
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• v.55 no.2
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• pp.33-39
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• 2019

Freeze-dried silkworm powder has been approved as a functional ingredients for blood glucose control since 2009. Proximate and nutrient compositions of silkworm powder was summerized as bellow. Silkworm powder contained 4.7% moisture, 57.7% crude protein, 9.5% crude fat, 5.4% crude fiber, and 9.3% ash. The larval protein contained 18 known amino acid including glutamic acid and aspartic acid. Fat is composed of 3:7 ratio of saturated fatty acid to unsaturated fatty acid including various essential fatty acids. It contained 34.7 linolenic acid, 24.4% oleic acid, 20.2% palmitic acid, 9.2% stearic acid, and 7.7% linoleic acid. Five minerals, K, P, Ca, Mg, S were abundant in the silkworm powder with other minerals such as Cu, Mn, Fe, and Zn.

• Journal of Nutrition and Health
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• v.54 no.3
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• pp.247-261
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• 2021

Purpose: This study was conducted to identify the association between insulin resistance and the major dietary patterns of Korean adults. Methods: This study used data from the 2015 Korea National Health and Nutrition Examination Survey. The subjects were 2,276 adults aged 19 to 64 years old. Based on the food frequency questionnaire data, 112 food items were reclassified into 30 food groups. The principal component analysis method was applied to identify major dietary patterns. We used homeostatic model assessment of insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI) value as indicators of insulin resistance. The association between major dietary patterns and insulin resistance was investigated using logistic regression analysis. Results: Three major dietary patterns were identified and assigned descriptive names based on the food items with high loadings: 'healthy Korean meal pattern', 'western meal pattern', and 'white rice, alcohol, meat pattern'. As the 'white rice, alcohol, meat pattern' score increased, significant increasing trends for fasting glucose concentration and HOMA-IR and a significant decreasing trend for QUICKI were observed after adjusting for age and sex. The odds ratio of insulin resistance according to the 'healthy Korean meal pattern' and the 'western meal pattern' were not statistically significant. the 'white rice, alcohol, meat pattern' showed a significant positive association with the risk of insulin resistance after adjusting for covariates. Conclusion: These results suggest that the 'white rice, alcohol, meat pattern' is positively associated with the risk of insulin resistance. The white rice, alcohol, meat pattern was related to the high consumption of alcohol together with rice or meat. This pattern was also associated with the high intake of sodium and low intakes of vitamin C, calcium, potassium, and dietary fiber. To confirm the association, further longitudinal studies are required.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.665-675
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• 2018

A total of 80 pigs [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] with an average body weight of $72.9{\pm}2.6kg$ were used in the present study to investigate the effects of fermented whole crop wheat and barley with or without supplementing inoculums throughout the restricted feeding in finishing pigs. There were 4 replicate pens per treatment. Pigs were fed ad libitum throughout the experiment as the control (CON), and the other four groups were restricted to 10% in the CON diet and fed ad libitum fermented whole crop cereals: fermented whole crop barley with inoculums; fermented whole crop barley without inoculums; fermented whole crop wheat with inoculums; and fermented whole crop wheat without inoculums. During the entire experiment, the average daily feed intake (ADFI) decreased in the fermented barley and fermented wheat groups compared to the CON, while no difference was observed in the average daily gain (ADG), feed efficiency (gain : feed ratio, G : F) between the control and fermented whole crop barley, wheat diet group. Dry matter and nitrogen digestibility did not show a significant difference among the treatments. In the blood constituents, concentrations of blood urea nitrogen were significantly lower in pigs fed fermented whole crop barley without inoculum diets compared with the other treatments. In conclusion, restricted feeding with fermented whole crop barley and wheat regardless of the supplementing inoculums showed no significant difference in growth performance compared to the CON. This suggests that there is a possibility that fermented whole crop barley and wheat could replace part of the conventional diets.