• Korean Chemical Engineering Research
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• v.51 no.1
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• pp.121-126
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• 2013

The objective of this research is to predict the TG curve of blends of bituminous coal and sub-bituminous coal during devolatilization. TSL (Thermal Shock Large) TGA was used for Experiments, and Coats-redfern method was used for reaction order calculation. Based on reaction order, sum method was verified to be suitable for a single coal, then, prediction and comparison of TG curve of coal blends was conducted using both of WSM (Weight Sum Method) and MWSM (Modified Weight Sum Method), where the latter was developed in this research. The presented experiment results and WSM & MWSM were showed to be reasonable using linear least square method. MWSM performed more accurately than WSM for the case that TG curve had different slopes and the case that sharp weight loss happened due to release of volatile matter. The results showed that it's possible to predict the thermal behavior of coal blends during devolatilization based on the thermal behavior of single coals.

• The Journal of Natural Sciences
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• v.4
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• pp.85-93
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• 1991

In solid reaction of the eqimolecular mixture of $BaCO_3$ and $TiO_2$, $CO_2$ generates by the following reaction ; $BaCO_3 + TiO_2\longrightarrow$ $BaTiO_3 + CO_2$ The solid reaction is studied as the kinetics of decomposition reaction with DTA-TG. The results are as follows. 1. $BaCO_3$ with is coexisted with $TiO_2$ decompose at lower temperature than pure $BaCO_3$. The reason is decreasing free eneragy of products. 2. Carter's equation is more important than Jander's equation in solid reaction of $BaCO_3$ decomposi-tion. The activation energy obtained by Carte r's equation is 42.8 Kcal/mol.

• Journal of Ginseng Research
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• v.37 no.1
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• pp.100-107
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• 2013

This study examined the effect of fermented ginseng (FG) on memory impairment and ${\beta}$-amyloid ($A{\beta}$) reduction in models of Alzheimer's disease (AD) in vitro and in vivo. FG extract was prepared by steaming and fermenting ginseng. In vitro assessment measured soluble $A{\beta}42$ levels in HeLa cells, which stably express the Swedish mutant form of amyloid precursor protein. After 8 h incubation with the FG extract, the level of soluble $A{\beta}42$ was reduced. For behavioral assessments, the passive avoidance test was used for the scopolamine-injected ICR mouse model, and the Morris water maze was used for a transgenic (TG) mouse model, which exhibits impaired memory function and increased $A{\beta}42$ level in the brain. FG extract was treated for 2 wk or 4 mo on ICR and TG mice, respectively. FG extract treatment resulted in a significant recovery of memory function in both animal models. Brain soluble $A{\beta}42$ levels measured from the cerebral cortex of TG mice were significantly reduced by the FG extract treatment. These findings suggest that FG extract can protect the brain from increased levels of $A{\beta}42$ protein, which results in enhanced behavioral memory function, thus, suggesting that FG extract may be an effective preventive or treatment for AD.

• Biomolecules & Therapeutics
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• v.21 no.4
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• pp.264-269
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• 2013

Silymarin has been introduced fairly recently as a hepatoprotective agent. But its mechanisms of action still have not been well established. The aim of this study was to make alcoholic fatty liver model of rats in a short time and investigate silymarin's protective effects and possible mechanisms on alcoholic fatty liver for rats. The model of rat's alcoholic fatty liver was induced by intragastric infusion of ethanol and high-fat diet for six weeks. Histopathological changes were assessed by hematoxylin and eosin staining (HE). The activities of alanine transarninase (ALT) and aspartate aminotransferase (AST), the levels of total bilirubin (TBIL), total cholesterol (TC) and triglyceride (TG) in serum were detected with routine laboratory methods using an autoanalyzer. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) and the level of malondialdehyde (MDA) in liver homogenates were measured by spectrophotometry. The TG content in liver tissue was determined by spectrophotometry. The expression of nuclear factor-${\kappa}B$ (NF-${\kappa}B$), intercellular adhesion molecule-1 (ICAM-1) and interleukin-6 (IL-6) in the liver were analyzed by immunohistochemistry. Silymarin effectively protected liver from alcohol-induced injury as evidenced by improving histological damage situation, reducing ALT and AST activities and TBIL level in serum, increasing SOD and GPx activities and decreasing MDA content in liver homogenates and reducing TG content in liver tissue. Additionally, silymarin markedly downregulated the expression of NF-${\kappa}B$ p65, ICAM-1 and IL-6 in liver tissue. In conclusion, Silymarin could protect against the liver injury caused by ethanol administration. The effect may be related to alleviating lipid peroxidation and inhibiting the expression of NF-${\kappa}B$.

• KSBB Journal
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• v.15 no.3
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• pp.226-231
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• 2000

Antibacterial activities of edible plant extracts were investigated to develop natural antimicrobial agents protecting horticultural products from spoiling-microorganisms during their storage. Crude extracts of Artemisa capillaris Allium tuberosum Ailanthus altissima Zanthoxylum pieperitum Pinus densiflora Morus alba lxeris dentata and Allium sativum showed remarkable antibacterial activities against Escherichia coli K 12 and Bacillus subtilis KCTC 1028 After solvent extraction of the crude extracts with n-hexane ethyl acetate chloroform and water in sequence each fractions was re-examined for the antbacterial activities. As results the ethyl acetate fractions of A. capillaris Aaltissima, P. densiflora and I. dentata and all fractions of Z. piperitum and A. sativium showed relatively strong antibacterial activities against E. coli and B. subtilis and the ethyl acetate fraction of A. altissima was the strongest(6mm and 7mm respectively) against two strawberry-spoiling bacteria isolated and identified at our laboratory as Staphylococcus sp. TG-101 and Staphylococcus sp. TG-102.

• Journal of the Korean Ceramic Society
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• v.30 no.4
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• pp.289-298
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• 1993

Properties in terms of the variation of the glass compositions, which were density (p), molar volume(Vm), atom/ion packing density (Dp), refractive index (nD), transformation temperature (Tg), dilatometric softening point (Td), thermal expansion coefficient (α), Young's modulus (E), and knoop hardness (KHN) were investigated in CaO-SiO2 glasses and CaO-P2O5-SiO2 glasses containing less than 10mole% of P2O5. Those properties were measured by density measurement kit, Abbe refractometer, dilatometer, ultrasonic pulse echo equipment, and micro hardness tester. When CaO content was increased in CaO-SiO2 glasses, p, Dp, nD, Tg, Td, α, E and KHN were increased, while Vm was decreased. When P2O5 was added to the CaO-SiO2 glasses with constant CaO/SiO2 ratio as 1.07, p, Dp, nD, Tg, Td, α, E and KHN were decreased, while Vm was increased. When the amount of P2O5 in glasses was kept constant, the changes of the properties with variation of CaO content in the CaO-P2O5-SiO2 glasses were very similar to those of CaO-SiO2 glasses. These phenomena could be explained by the structural role of P2O5 in the CaO-P2O5-SiO2 glasses, which was polymerization of siicate structures and resulted in [PO4] monomer structure in glasses. Due to this structural characteristics, the bond strength and packing density were changed with compositions. Proportional relationships between 1) np and Dp, 2) Tg, Td, α and CaO content, 3) E and Vm-1, and 4) KHN and P2O5 content were evaluated in this investigation.

• Journal of Nutrition and Health
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• v.26 no.1
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• pp.56-66
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• 1993

Interactive effects among eating behavior, obesity and serum lipid levels were studied in 117, 4~12 year old children residing suburban Seoul. Fasting blood samples are obtained and analyzed for serum triglycerides (TG), total cholesterol(TC), high density lipoprotein-cholesterol(HDL-C) and hematochrit. Obesity was determined by weight for length index(WLI)and the information on eating behavior including food habits and dietary intakes was obtained by questionaire using food record method for 2-consecutive days. Over 40% of children was classified overweight or obese by WIL and children's physical parameters were closely related to those of parents implying genetic influence on obesity. Although it did not reach the statistical significance, there was a tendency of higher TG, TC and low density lipoprotein-cholesterol(LDL-C)levels among girls compared to boys. Blood lipid levels of obese children were similar to those of other groups except TG, which was significantly higher(p<0.05) in obese group. Nutrient intakes seemed adequate in all subjects except iron, calcium and total calorie which were lower than RDAs. Lacking significant relationship between individual nutrient intake and obesity, there was significant correlation between food intake and blood lipid level especially in 10-12 year old group. Vegetable intake was negatively related to TG, LPH(LDL-C/HDL-C) and atherogenic index(AI), and positively to HDL-C. Skipping breakfast and frequent eating out appeared to cause imbalances in nutrient intake. These findings clearly revealed the influence of eating behavior on childhood obesity along with blood lipid profile. To ensure the proper growth and health of these children, devising method and developing media for nutrition education suited to our society should be accomplished first. With well-planned nutrition surveys and thorough intention, childhool obesity could be prevented from progress into adulthood obesity.

• Journal of Nutrition and Health
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• v.39 no.8
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• pp.773-785
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• 2006

Vitamin E in the body system plays an important role in preventing chronic diseases by decreasing the oxidative stress by free-radicals. However, there are not enough researches on analyzing the primary factors affecting vitamin E levels in the blood in Korean adults. Therefore, the purpose of this research was to examine blood tocopherol levels and the primary factors affecting the status. A complete lifestyle survey was performed on 314 Korean adult men and surveyed their smoking, drinking and exercising habits. The average plasma level of ${\alpha}-\;and\;{\gamma}-tocopherol$ showed similar mutual relations with plasma total cholesterol (TC), triglyceride (TG), or low density lipoprotein cholesterol (LDL-C) levels (p<0.001). Plasma ${\alpha}-tocopherol$ level of the subjects did not show any difference as smoking, drinking and exercising habits changed. However, ${\gamma}-tocopherol$ per TG showed much lower figure in smokers than non smokers (p < 0.05). Amongst diet factors, plasma ${\alpha}-tocopherol$ level showed negative correlations with Vitamin E intake, while ${\gamma}-tocopherol$ level showed positive correlations with Vitamin E intake. Erythrocyte superoxide dismutase (SOD) activity and plasma tocopherol showed negative correlations, and catalase activity and plasma ${\alpha}-tocopherol$ showed positive correlationship. The level of cell DNA damage of Iymphocyte and plasma ${\alpha}-\;or\;{\gamma}-tocopherol$ showed negative correlations. As a result of this research, the factors that affect Korean adult men's plasma ${\alpha}-tocopherol$ level are plasma TG, LDL-C and cell DNA damage in Iymphocyte, while the factors that affect ${\gamma}-tocopherol$ level are plasma TG, LDL-C and vitamin E intake based on multiple regression analysis. These findings implies that the level of different types of tocopherol depends on slightly different factors. A further research is needed on the factors involved in the differentiation of the types of tocopherol.

• Journal of Adhesion and Interface
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• v.20 no.4
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• pp.135-139
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• 2019

In this work, flame retardant acrylic emulsion pressure sensitive adhesives were newly polymerized combining phosphorous flame retardant monomer and acrylic monomer like butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, acrylic acid, and 2-hydroxyethyl methacrylate. The process of polymerization showed 100% of conversion at solid content of 65%, and viscosity of acrylic emulsion was increased up to 5500 cps when phosphorous flame retardant monomer was added into acrylic emulsion. The structure of flame retardant acrylic emulsion was identified using FT-IR and thermal properties like glass transition temperature (Tg) were checked by differential scanning calorimeter (DSC). Acrylic emulsion without phosphorous flame retardant monomer had Tg of -44.1℃ and peel strength of 2,100gf/inch, however, flame retardant acrylic emulsion showed maximum Tg (-31.4℃) and peel strength of 200gf/inch when 15 part of phosphorous flame retardant monomer was added. Flammability test was also conducted to confirm the application of flame retardant acrylic emulsion as the flame retardant addtive.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.62-66
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• 2013

Purpose: I-131 is a radioisotope widely used for thyroid gland treatments. The physical half life is 8.01 and characterized by emitting beta and gamma rays which is used in clinical practice for the purpose of acquiring treatment and images. In order to reduce the recurrence rate after surgery in high-risk thyroid cancer patients, the remaining thyroid tissue is either removed or the I-131 is used for treatment during relapse. In cases of using a high dosage of radioactive iodine requiring hospitalization, the patient is administered dosage in the hospital isolation ward over a certain period of time preventing I-131 exposure to others. By checking the radiation amount emitted from patients before discharge, the patients are discharged after checking whether they meet the legal standards (50 uSv/h). After patients are discharged from the hospital, the contamination level is checked in many parts of the ward before the next patients are hospitalized and when necessary, decontamination operations are performed. It is expected that there is exposure to radiation when measuring the ward contamination level and dose check emitted from patients at the time of discharge whereby the radiation exposure by health workers that come from the patients in this process is the main factor. This study analyzed the correlation between discharge dose of patients and ward contamination level through a variety of factors such as renal functions, gender, age, dosage, etc.). Materials and Method: The study was conducted on 151 patients who received high-dosage radioactive iodine treatment at Soon Chun Hyang University Hospital during the period between 8/1/2011~5/31/2012 (Male: Female: 31:120, $47.5{\pm}11.9$, average dosage of $138{\pm}22.4$ mCi). As various factors expected to influence the patient discharge dose & ward contamination such as the beds, floors, bathroom floors, and washbasins, the patient renal function (GFR), age, gender, dosage, and the correlation between the expected Tg & Tg-Tb expected to reflect the remaining tissue in patients were analyzed. Results: In terms of the discharge dose and GFR, a low correlation was shown in the patient discharge dose as the GFR was higher (p < 0.0001). When comparing the group with a dosage of over 150mCi and the group with a lower dosage, the lower dosage group showed a significantly lower discharge dose ($24{\pm}10.4uSv/h$ vs $28.7{\pm}11.8uSv/h$, p<0.05). Age, gender, Tg, Tg-Tb did not show a significant relationship with discharge dose (p> 0.05). The contamination level in each spot of the treatment ward showed no significant relationship with GFR, Tg, Tg-Tb, age, gender, and dosage (p>0.05 ). Conclusion: This study says that discharge of the dose in the patient's body is low in GFR higher and Dosage 150mCi under lower. There was no case of contamination of the treatment ward, depending on the dose and renal association. This suggests that patients' lifestyles or be affected by a variety of other factors.