• Journal of the Korean Society for Precision Engineering
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• v.9 no.2
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• pp.29-35
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• 1992

The distribution of magnetic flux density of electro-magnetic chucks may clarify the clamping characteristics which are strongly related to the machining efficiency and machining accuracy in a surface grinder. Therefore the distribution of the normal and the tangential components of magnetic flux density has been analyzed theoretically. It appears that the normal and the tangential components of magnetic flux density increase as the ratio of the separator width to the pitch e/p decreases. The results seem to increase the uniformity and stability of normal component of magnetic flux density for the decreased e/p.

• Journal of the Korean Mathematical Society
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• v.44 no.6
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• pp.1291-1312
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• 2007

We study some extremal problems on the Cartan-Hartogs domains. Through computing the minimal circumscribed Hermitian ellipsoid of the Cartan-Hartogs domains, we get the $Carath\acute{e}odory$ extremal mappings between the Cartan-Hartogs domains and the unit hyperball, and the explicit formulas for computing the $Carath\acute{e}odory$ extremal value.

• Journal of Nutrition and Health
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• v.36 no.7
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• pp.691-698
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• 2003

The purpose of this study was to investigate the effect of vitamin E on the cadmium accumulation in body, cadmium excretion and detoxification functions in chronic cadmium poisoned rats. Sprague-Dawley male rats weighing 100$\pm$10 g were randomly assigned to one normal group and three cadmium poisoned groups. Cadmium poisoned groups were classified to vitamin E free diet (Cd-0E group), vitamin E 40 mg/kg diet (Cd-400E group) and 400 mg/kg diet (Cd-400E group) according to the levels of vitamin E supplement. Animals were maintained on 0, 40 mg and 400 mg vitamin E/kg diets for 20 weeks and simultaneously administered 50 ppm Cd$^{2+}$ dissolved in the drinking water. Body weight, food intakes and food efficiency ratio were significantly decreased in all cadmium groups, compared with those of normal group. The accumulation of cadmium in rat liver, kidney and blood was reduced by sufficient vitamin E supplementation. The metallothionein (MT) content in liver and kidney were increased in all cadmium groups compared with that of normal group. The ratio of cadmium absorption and retention were significantly decreased in vitamin E supplementation groups. Accordingly, vitamin E supplementation resulted in an excretion of cadmium in urine and feces and a lowered accumulation of cadmium in liver and kidney. It can be suggested that increased MT synthesis lead to the significant decrease in cadmium absorption and retention ratios.s.

• Honam Mathematical Journal
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• v.46 no.4
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• pp.617-628
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• 2024

In this paper, first we generalize the notion of polygroups and weak polygroups by the notion of E-polygroups and weak E-polygroups. Then, we study the isomorphism theorems on E-polygroups and weak E-polygroups. Finally, the fundamental relations on weak E-polygroups are investigated.

• Journal of Nutrition and Health
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• v.41 no.5
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• pp.402-413
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• 2008

This study was performed to investigate Apolipoprotein E phenotypes and the relationship among lipid levels, nutrient intakes, lifestyles and risk factors between subjects with and without hyperlipidemic risk. The data were collected from 675 industrial male workers who had completed annual medical examination. Compared to the normal group, the hyperlipidemic risk group in Apo E3 and E4 had significantly higher BMI (p < 0.05) and showed significantly higher body fat (%), waist circumference and WHR in all types of Apo E (p < 0.05). In addition, the hyperlipidemic risk group had significantly higher total cholesterol, LDL-cholesterol, triglyceride and AI than the normal group in all types of Apo E (p < 0.05). Intakes of protein, calcium, phosphorus, iron, vitamin A, vitamin B1, vitamin B2, vitamin C and niacin in Apo E3 were significantly lower in the hyperlipidemic risk group than in the normal group (p < 0.05). In the logistic regression analysis, after adjustment for other factors, Apo E2 + E4, waist and WHR were the significant risk factors associated with hyperlipidemia, but protein intakes were associated with significantly lower risks of hyperlipidemia (p < 0.05). In conclusion, genetic factor (Apo E2 or Apo E4), anthropometric index and nutrient intake seem to influence hyperlidemic risk. Further studies and efforts will be needed to evaluate the independent relationships among hyperlipidemic risk factors.

• Nutritional Sciences
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• v.8 no.2
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• pp.133-139
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• 2005

Objective: The purpose of this study was to determine serum antioxidant nutrients and the relationship between serum antioxidants and risks of chronic diseases in obese Korean children Methods: Normal weight Korean school children (0=170), mean age of 11.5$\pm$1.5, and obese (body fat mass > $28\%$) children (0=176), mean age of 11.0$\pm$1.8, were recruited Fat mass ($\%$) was determnined by Bioelectrical Impedance (BEI), and body mass index (BMI) was calculated Fasting blood was collected to measure serum antioxidant nutrients, vitamin A, vitamin E and zinc. Serum lipid profiles including total cholesterol (TC), high density cholesterol (HDL) and triglyceride (TG), and blood glucose, glutamic oxaloacetic transaminase (GOT), and glutamic pyruvic transaminase (GPI) were also determined. Differences in serum blood measurements between obese and normal children were assessed by independent t test. Pearson's correlation analysis was used to determine the relationship between variables. Results: Blood glucose, GPT, total cholesterol, and triglycerides concentrations were significantly higher among obese boys, compared to normal boys (p<005). Significantly lower concentrations of serum vitamin E, after adjustment for TG and TC, was shown in obese boys (0.26 mg/mg) and obese girls (0.31 mg/mg), compared to normal boys (0.36 mg/mg) and girls (0.38 mg/mg) (p<0.05). Fat mass ($\%$) was negatively con-elated with serum vitamin A and vitamin E. Conclusion: Obese Korean children showed insufficient serum vitamin E concentration and increased risk for diabetes, atherosclerosis, and liver disease. Since lower vitamin E concentration was negatively con-elated with atherogenic index, improved vitamin E status in children may decrease the risk of atherosclerosis later in life.

• The Korean Journal of Applied Statistics
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• v.29 no.3
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• pp.513-523
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• 2016

Fitting a mixture of multivariate skew normal distribution (MSNMix) with multiple skewness parameter vectors via EM algorithm often requires a highly expensive computational cost to calculate the moments and probabilities of multivariate truncated normal distribution in E-step. Subsequently, it is common to fit an asymmetric data set with MSNMix with a simple skewness parameter vector since it allows us to compute them in E-step in an univariate manner that guarantees a cheap computational cost. However, the adaptation of a simple skewness parameter is unrealistic in many situations. This paper proposes an approximate estimation for the MSNMix with multiple skewness parameter vectors that also allows us to treat them in an univariate manner. We additionally provide some experiments to show its effectiveness.

• Restorative Dentistry and Endodontics
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• v.49 no.2
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• pp.19.1-19.3
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• 2024

• Journal of Preventive Medicine and Public Health
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• v.45 no.4
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• pp.251-258
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• 2012

Objectives: The purpose of this paper was to elucidate the potential methylation levels of adjacent normal and cancer tissues by comparing them with normal colorectal tissues, and to describe the correlations between the methylation and clinical parameters in Korean colorectal cancer (CRC) patients. Methods: Hypermethylation profiles of nine genes (RASSF1, APC, $p16^{INK4a}$, Twist1, E-cadherin, TIMP3, Smad4, COX2, and ABCB1) were examined with 100 sets of cancer tissues and 14 normal colorectal tissues. We determined the hypermethylation at a given level by a percent of methylation ratio value of 10 using quantitative methylation real-time polymerase chain reaction. Results: Nine genes' hypermethylation levels in Korean CRC patient tissues were increased more higher than normal colorectal tissues. However, the amounts of $p16^{INK4a}$ and E-cadherin gene hypermethylation in normal and CRC tissues were not significantly different nor did TIMP3 gene hypermethylation in adjacent normal and cancer tissues differ significantly. The hypermethylation of TIMP3, Ecadherin, ABCB1, and COX2 genes among other genes were abundantly found in normal colorectal tissues. The hypermethylation of nine genes' methylation in cancer tissues was not significantly associated with any clinical parameters. In Cohen's kappa test, it was moderately observed that RASSF1 was related with E-cadherin, and Smad4 with ABCB1 and COX2. Conclusions: This study provides evidence for different hypermethylation patterns of cancer-associated genes in normal and CRC tissues, which may serve as useful information on CRC cancer progression.

• Journal of Life Science
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• v.14 no.5
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• pp.732-740
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• 2004

MCM proteins are essential for eukaryotic DNA replication, playing roles in the initiation and elongation of DNA replication. MCM proteins expression is much higher in malignant tissues than normal tissues. Several reports have indicated the usefulness of MCM proteins as markers of cancer cells in histopathological diagnosis. However, the cause of enhanced expression of MCM proteins in cancer cells remain to be clarified. The purpose of this study is to examine the relative transcriptional activities of human mcm gene promoters in cancer and normal cells. The minimal promoter region required for transcription of a luciferase reporter gene was contained an E-box and one E2F site. In addition, luciferase activities from mcm7 and mcm2 promoter/luciferase gene reporter constructs were significantly increased in cancer cells at 8 times compared with normal cells. E-box and E2F binding site in the promoter of mcm genes are responsible for different mechanism of transcription regulation on the cellular environment.