• Journal of Korea Foundry Society
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• v.41 no.6
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• pp.516-520
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• 2021

During sand casting, the binders produces gases in cores because high temperature molten metals dissolve the binders into gases and causes gas defects in the casting products. In the present study, quantitative analysis of inorganic binder gas generation was performed using Thermo Gravimetry (TG) and Mass Spectrometer (MS) analyses. The specimen was prepared using organic binders in liquid and solid state, and a mixture of sand and binders. Moisture loss by catalysts was calculated by TG results from liquid and solid binder specimens; it was found that components of gases were different. Quantitative analysis was discussed for generated gases with individual gas component results obtained using TG and MS. It is expected that gas generation can be predicted in the casting simulation using the technique proposed in the present study.

• Environmental Engineering Research
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• v.25 no.4
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• pp.522-528
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• 2020

To achieve the clean and efficient utilization of low-rank coal, the combustion and pollutant emission characteristics of chars from low-temperature and fast pyrolysis in a horizontal tube furnace were investigated in a TG-MS analyzer. According to the results, the combustion characteristic of chars was poorer than its parent coals. The temperature range of gaseous product release had a good agreement with that of TGA weight loss. Gaseous products of samples with high content of volatile were released earlier. The NO and NO₂ emissions of chars were lower than their parent coals. Coals of high rank (anthracite and sub-bituminous) released more NO and NO₂ than low rank coals of lignite, so were chars from coals of different ranks. SO₂ emissions of char samples were lower than parent coals and did not show obvious relationship with coal ranks.

• Applied Chemistry for Engineering
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• v.30 no.6
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• pp.707-711
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• 2019

The feasibility of waste concrete as a catalyst for the effective pyrolysis of polyethylene terephthalate (PET) was examined using thermogravimetric (TG) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) analyses. TG analysis results indicated that the maximum decomposition temperature of PET is not altered by the use of waste concrete, showing similar values (407 ℃ and 408 ℃ at 5 ℃/min). Meanwhile, the volatile product distribution data obtained from the Py-GC/MS analysis revealed that the use of waste concrete promoted the deoxygenation reaction via converting the oxygen containing products such as benzoic acids, benzoates, and terephthalates to valuable deoxygenated aromatic hydrocarbons including benzene, toluene, ethylbenzene, and styrene. This suggests that the waste concrete can be used as a potential catalyst for the production of valuable aromatic hydrocarbons from PET pyrolysis.

• Korean Journal of Community Nutrition
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• v.17 no.5
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• pp.530-542
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• 2012

The purposes of this study were to investigate blood profiles and nutrient intakes of groups that are different in obese levels, and to find the credible predictor of insulin resistance. The subjects were classified as normal weight (%IBW${\leq}$ 110), obese without MS and obese with MS according to IDF definition of the risk group in metabolic syndrome (MS). Subjects of this study were included 137 (59 boys, 78 girls) free living children and adolescents (mean age $12.6{\pm}3.4$ years) in Gangneung area, South Korea. %IBW of normal weight (94.9%), obese without MS (123.8%) and obese with MS (131.5%) were significantly different among groups. HOMA-IR had positive correlations with TG (r = 0.634), waist circumference (r = 0.553), atherogenic index (r = 0.513), %IBW (r = 0.453) and ALT (r = 0.360), but showed negative correlations with HDL cholesterol (r = -0.417, p < 0.001). HOMA-IR showed positive correlation with polyunsaturated fatty acid intake (p < 0.05). The energy intake of obese with MS was 1762 kcal/day which was not significantly different from those of normal weight and obese without MS. Total fatty acid intakes of two obese groups were significantly higher than that of normal weight. The results of this study suggest that waist circumference and ALT as well as TG, atherogenic index and weight can be credible indices to predict the insulin resistance in children and in adolescents. In addition, nutrition education and adequate diet should be provided to prevent MS in children and in adolescents.

• Korean Journal of Community Nutrition
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• v.13 no.1
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• pp.91-99
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• 2008

The present study was conducted to examine metabolic risk factors and total antioxidant capacity (TAC) of Korean females living in Seoul and to investigate the relationship between the metabolic risk factors and serum TAC. A total of 353 females aged between 20 and 64 participated in the study. Obesity indicators, blood pressure, serum lipid profile and fasting blood glucose were measured as metabolic risk factors. Ferric reducing antioxidant power (FRAP) assay was employed to determine serum TAC of subjects. Obesity indicators such as body mass index, waist circumference and waist-hip ratio were significantly higher in the participants aged $\geq$ 50 y (older group) than in the participants aged 20-49 y (younger group) (p < 0.001). Blood pressure, serum total cholesterol (TC), triglyceride (TG) and fasting blood glucose were also significantly higher in the older group than in the younger group (p < 0.001), demonstrating significant positive correlations between age and MS risk factors. The association between FRAP and MS risk factors were also investigated. FRAP values showed significant positive correlations with age (p = 0.001), serum TG (p = 0.002) and TC (p = 0.03). A tendency of positive association between FRAP and waist circumference was observed without any significant difference (p = 0.06). Increased serum FRAP with central obesity and serum lipids may be interpreted as results of activation of antioxidant defense system against oxidative stress induced by metabolic syndrome (MS) constituent factors. However, to verify the function of FRAP as a potential biomarker of susceptibility to MS various contributors to the plasma antioxidant capacity and their biological relevance related to MS should be elucidated further.

• Journal of Community Nutrition
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• v.6 no.3
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• pp.141-145
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• 2004

The purpose of this study was to explore the relationship between life style and metabolic syndrome. The cross-sectional survey was conducted in Pingliang community in Shanghai in Jan 2003. The data was collected by questionnaire, and the results were analyzed by SPSS. It was found that the prevalence of Metabolic Syndrome (MS) was $13.4\%$ in the community, and the body mass index (BMI), waist-to-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), serum triglyceride (TG), total cholesterol(TC), low density lipoprotein-cholesterol (LDL-C), and fast plasma glucose (FPG) in MS group were higher than that in non-MS group. Logistic regression analysis indicated that BMI and WHR were positively correlated to the prevalence of MS, and physical activity was negatively correlated to the prevalence of MS. People with higher education levels (${\geq}10y$) had lower BMI, SBP, DBP, LDL-C and FPG. The prevalence of MS in the higher education level group was significantly lower than that of the lower education level group. These results suggested that BMI, WHR and physical activity were important factors of MS, and education background played an important role in the occurrence of MS. Therefore, it is very important to build a healthy life style for preventing and controlling the incidence and developing of MS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.389-394
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• 2000

CLA의 glycerol 유도체를 화학적으로 합성하였다. CLA-Cl(1.79 mmole), glycerol(0.6 mmole)과 pyridine (1.3mL)를 25C에서 8시간 반응시켰다. 이 반응물을 SGCC와 TLC를 이용하여 CLA의 glycerol 유도체를 분리하고 1H-NMR, 13C-NMR, IR, MS를 이용하여 분리된 유도체를 동정하였다. 이 실험조건하에서 사용된 CLA의 59.4%가 CLA의 glycerol 유도체(CLA-TG, CLA-DG, CLA-MG)로 전환되었다. CLA의 glycerol 유도체 중 CLA-TG는 52.1%, CLA-DG는 17.0%, CLA-MG는 30.9%였다.

• Journal of Community Nutrition
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• v.6 no.3
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• pp.131-136
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• 2004

The purpose of this study is to compare the relative risk of metabolic syndrome (MS) in middle aged adults with different body weights. 155 subjects living in urban Beijing were recruited from 24 neighborhood committees of urban Beijing. They were divided into normal weight, overweight and obese groups according to their BMIs. The general information of the subjects was collected using an interview-administered questionnaire. Standard procedure was followed to measure subject's weight, height and waist. Biochemical parameters (total cholesterol (TC), low- and high­density lipoprotein cholesterol (LDL-C ; HDL-C), triglyceride (TG), and fasting glucose) and blood pressure were also determined. The results indicated that the systolic and diastolic blood pressure, HDL-C of obese group was lower than that of the normal weight group. Fasting glucose of obese males was significantly higher than that of normal weight males. No significant difference of fasting glucose was found among female groups. No significant difference of TG was found among male groups, while TG of overweight and obese females was both significantly higher than normal weight females. There was no significant difference of TC and LDL-C among normal weight, overweight and obese groups in both males and females. The MS rate of obese males was significantly higher than the normal weight and overweight males, as was the female. The relative risk of MS in obese group was about 11 times higher (OR=11.249, $95\%CI$ = 3.812 - 33.191) than the normal weight group after adjusting for age, gender, smoking, drinking, family economic level and education status. It is concluded that obesity contributed to lower HDL-C, hypertriglyceride, hypertension and MS after controlling the effects of age, gender, socioeconomic status, alcohol drinking and smoking. Obese individuals have a higher risk of having MS than their normal weight counterparts.

• Biomedical Science Letters
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• v.19 no.1
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• pp.9-16
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• 2013

Elevated blood triglyceride (TG) levels correlate with development of atherosclerosis suggesting that TG may promote the development of this disease. During atherosclerosis, TG is taken up by tissue macrophages which result in dramatic changes in various secreted factors. One such factor is the family of matrix metalloproteases (MMP) which are involved in tissue remodeling during both physiological and pathological processes. In this study, we examined the MMP expression profile in PMA-differentiated THP-1 macrophages treated with TG. We found that TG-treated THP-1 macrophages showed decreased expression of MMP-3, MMP-7, MMP-8 and MMP-9 in a time- and dose-dependent manner. In contrast, expression of MMP-1, MMP-2, and MMP-10 remained relatively unchanged after TG treatment. In addition, we found that expression of select MMPs was affected by various inhibitors of signaling pathways. In particular, expression of MMP-3 was slightly recovered by cRAF and PLC signaling pathway inhibitors. These data suggests a possible role of MMPs in macrophages during TG-induced atherosclerosis.

• Korean Journal of Community Nutrition
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• v.15 no.6
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• pp.783-795
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• 2010

This study was intended to investigate the risk of metabolic syndrome (MS) in healthy 92 male smokers (mean age: $44.4\;{\pm}\;7.8\;yrs$). We investigated the anthropometric assessment and dietary intake survey for 2 days by 24-recall method, also blood pressure and serum lipids were measured. The average numbers of cigarettes smoking a day were 21.3/d, smoking duration were 21.5 years. The proportion of fat energy was 24.9% and intakes of vitamin B2, folate, calcium, potassum and fiber were lower than KDRI. The body mass index (BMI) and body fat % were 24.8, 23.9% respectively. The systolic ($134.1\;{\pm}\;1.4\;mmHg$) and the diastolic blood ($87.9\;{\pm}\;1.1\;mmHg$) pressure were in borderline hypertension. Among biochemical parameters, TG ($173.6\;{\pm}\;9.4\;mg/dL$) and fasting blood glucose ($109.0\;{\pm}\;2.4\;mg/dL$) levels were out of normal values. The most occurred problem among the risk factors related to MS was the borderline hypertension (63%) in subjects. Regarding the correlations of anthropometric data with biochemical factors, TG was significantly correlated with the BMI, body fat % and waist circumference. Smoking years showed positive correlation with AI. These results suggest that the smoking habit has significant relations with the risk factors of MS. Therefore, quitting is necessary to prevent MS, and nutrition education and dietary management program are required to prevent the degenerative disease.