• Clinical and Experimental Pediatrics
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• v.46 no.3
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• pp.259-264
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• 2003

Purpose : We have performed an analysis on patients who received Rastelli operation in our institute and reviewed their progress postoperatively. Various factors with suspected relationship to the outcome have been considered to help in future treatment and follow-up. Methods : We analyzed retrospectively 43 patients who either received Rastelli operation in Yonsei University Cardiovascular Center from March 1995 to April 1997 or who received post-procedural cardiac catheterization and follow-up echocardiography in the out-patient department after the procedure. Results : No statistically valid relationships were found between the age of the patient, their body weight, preoperative pulmonary arterial index and pressure, presence of pulmonary branchial stenosis and postoperative results. Cases with atrioventricular concordance showed lower age and body weight, and discordant cases exhibited lower ejection fraction 3 days postoperatively. Upon follow up, lower NYHA score was seen in patients with severe residual stenosis. In the group that received cardiac catheterization after the procedure, residual stenosis and right ventricular pressure measurement in echocardiography showed good correlation with the catheterization data. Conclusion : In cases where conduit insertions of the right ventricular outflow tract are required to achieve total correction in complex cardiac deformity, early operation does not seem to provide a clear risk to the patient. In patients with atrioventricular discordance, careful postoperative observation of the ventricular function seems to be needed. Also, echocardiography appears to be a sound method in follow-up of patients after the correctional procedure.

• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.241-254
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• 2011

Financial time-series forecasting is one of the most important issues because it is essential for the risk management of financial institutions. Therefore, researchers have tried to forecast financial time-series using various data mining techniques such as regression, artificial neural networks, decision trees, k-nearest neighbor etc. Recently, support vector machines (SVMs) are popularly applied to this research area because they have advantages that they don't require huge training data and have low possibility of overfitting. However, a user must determine several design factors by heuristics in order to use SVM. For example, the selection of appropriate kernel function and its parameters and proper feature subset selection are major design factors of SVM. Other than these factors, the proper selection of instance subset may also improve the forecasting performance of SVM by eliminating irrelevant and distorting training instances. Nonetheless, there have been few studies that have applied instance selection to SVM, especially in the domain of stock market prediction. Instance selection tries to choose proper instance subsets from original training data. It may be considered as a method of knowledge refinement and it maintains the instance-base. This study proposes the novel instance selection algorithm for SVMs. The proposed technique in this study uses genetic algorithm (GA) to optimize instance selection process with parameter optimization simultaneously. We call the model as ISVM (SVM with Instance selection) in this study. Experiments on stock market data are implemented using ISVM. In this study, the GA searches for optimal or near-optimal values of kernel parameters and relevant instances for SVMs. This study needs two sets of parameters in chromosomes in GA setting : The codes for kernel parameters and for instance selection. For the controlling parameters of the GA search, the population size is set at 50 organisms and the value of the crossover rate is set at 0.7 while the mutation rate is 0.1. As the stopping condition, 50 generations are permitted. The application data used in this study consists of technical indicators and the direction of change in the daily Korea stock price index (KOSPI). The total number of samples is 2218 trading days. We separate the whole data into three subsets as training, test, hold-out data set. The number of data in each subset is 1056, 581, 581 respectively. This study compares ISVM to several comparative models including logistic regression (logit), backpropagation neural networks (ANN), nearest neighbor (1-NN), conventional SVM (SVM) and SVM with the optimized parameters (PSVM). In especial, PSVM uses optimized kernel parameters by the genetic algorithm. The experimental results show that ISVM outperforms 1-NN by 15.32%, ANN by 6.89%, Logit and SVM by 5.34%, and PSVM by 4.82% for the holdout data. For ISVM, only 556 data from 1056 original training data are used to produce the result. In addition, the two-sample test for proportions is used to examine whether ISVM significantly outperforms other comparative models. The results indicate that ISVM outperforms ANN and 1-NN at the 1% statistical significance level. In addition, ISVM performs better than Logit, SVM and PSVM at the 5% statistical significance level.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.647-656
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• 2017

Purpose: This study investigated the relationship between vitamin D level and dyslipidemia in Korean adults aged 19 years and older. The data for analysis were obtained from the sixth Korea National Health Nutrition Examination Survey 2013 and 2014. Result: This study showed that 74.4% of the specified adult population had vitamin D deficiency. Moreover, the prevalence of dyslipidemia was found to be 39.6% in the same population. Dyslipidemia differed significantly according to gender (p<0.001), age (p<0.001), smoking status (p<0.001), subjective health status (p<0.001), BMI (p<0.001), blood pressure (p<0.001), FBS (p<0.001), physical activity (p<0.001), and vitamin D level (p<0.001). When vitamin D deficiency was less than 20.0 ng/mL, there was a significant risk of dyslipidemia with an odds ratio of 1.29 (95% Cl, 1.11-1.51). The relationship between vitamin D level and a diagnosis index of dyslipidemia with controlled status of physical activity was statistically significant; in Korean adults, the odds ratio for total cholesterol was 1.41 (95% CI, 1.04-1.81) and for triglyceride was 1.36 (95% CI, 1.11-1.66). Conclusion: Our results showed the relationship between vitamin D level and dyslipidemia was significant in Korean adults, and total cholesterol and triglycerides, which are indicators of dyslipidemia, was significant. Future studies, such as a more systematic cohort study investigating the relationship between vitamin D level and dyslipidemia may be helpful in confirming the causal relationship between vitamin D and dyslipidemia.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.1
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• pp.37-45
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• 2010

The effects of an Acanthopanacis cortex water extract on lipid levels, lipid peroxide, total antioxidant status and antioxidant enzyme activities were evaluated in rats fed one of the following diets for six weeks: normal diet and deionized water (ND), normal diet and Acanthopanacis cortex water extract (NDC), high fat diet and deionized water (HFD), high fat diet and Acanthopanacis cortex water extract (HFDC). The food intakes were significantly lower, but the food efficiency ratios were significantly higher in the high fat diet groups. The level of HDL-cholesterol in the plasma was significantly increased and the levels of LDL-cholesterol and triglyceride in the plasma were significantly decreased by the Acanthopanacis cortex water extract in the high fat diet groups. As a a result, the AI (atherogenic index) and CRF (cardiac risk factor) were significantly lower in the high fat diet groups that were treated with Acanthopanacis cortex water extract. The triglyceride and the total cholesterol of the liver were also significantly upregulated in the high fat diet groups, while the total cholesterol of the liver decreased in response to treatment with Acanthopanacis cortex water extract (HFDC). The plasma and liver concentrations of thiobarbituric acid reactive substances (TBARS) were significantly reduced by the addition of Acanthopanacis cortex water extract to the normal diet groups. The total antioxidant status (TAS) in the plasma was significantly upregulated by adding Acanthopanacis cortex water extract to the high fat diet groups. The activities of SOD, catalase and GST were also significantly higher in the Acanthopanacis cortex water extract groups when compared to the ionized water groups. The activity of GSH-Px and the concentration of GSH in the liver were significantly higher following the addition of Acanthopanacis cortex water extract to the high fat diet groups. Taken together, these results suggest that a supplementation of the diet of rats fed a high fat diet with Acanthopanacis cortex water extract improves lipid metabolism, reduces lipid peroxide and improves the activities of antioxidant enzymes, which may have favorable effects on antioxidant systems by improving the total antioxidant status (TAS).

• Korean journal of communication and information
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• v.43
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• pp.173-208
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• 2008

This study analyses the business performance according to the business diversification of Korean mass media enterprises from year 2003 to 2006. The conclusions drawn which could be divided into five main parts are the followings: First, newspaper companies pursue unrelated diversification in various industrial areas, in order to gain maximum profit while broadcasting companies exert themselves to provide better service by diversifying the major contents. Second, overall the interviewed companies display a constant decline in profit gained from their major business area thus establishing strategies to broaden their focus on diversification of any sort. Third, the researcher completed group analysis in regard of diversification measure resulting in division of three groups. The group which had the most immense diversification range gained the highest ROE, the lowest ROE volatility, and lesser probability of risk taking. The analysis adresses the companies broadening their business areas by researching and focusing on diversification are relatively stable in terms of the profit they gain. Fourth, the middle level group in terms of sales scale, debts, enterprise history, major share rate and high ROE group carry out diversification progressively. The sales scale affects positively to diversification, while the major share rate affects negatively to diversification. Fifth, in accordance to the research, diversification overall contributes to obtainance of successful outcome. Since there was not an immense amount of studies to be referred in the media area, the researcher interviewed and did panel discussion with numerous strategists and managers who are in charge of diversification of media companies. However, collection of only 4 years of data limits the research to be considered to be a generalized study, and does not reflect time gap between business diversification and business performance. Development is required in future studies to be established regarding the media companies' specificity different to other industries, classified the media companies into media types, and consider the time gap in the diversification activities and business performance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.1
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• pp.49-56
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• 2012

This study examined the effects of baked garlic powder on the lipid metabolism in rats fed a high-fat/highcholesterol diet for 4 weeks to induce hyperlipidemia. Male Sprague-Dawley rats were assigned to four groups according to the dietary fat, cholesterol and baked garlic powder levels. The experimental groups were normal diet group (N), a high-fat/high-cholesterol diet group (C), a high-fat/high-cholesterol diet with 1.5% baked garlic powder group (GPL) and a high-fat/high-cholesterol diet with 3% baked garlic powder group (GPH). The body weight gain, food intake and food efficiency ratio were similar in the experimental groups. The epididymal adipose tissues weight of the C group was higher than that of the N group, whereas those of the groups fed baked garlic powder were decreased gradually. The ALT and ALP activities were similar in the C groups, but the serum AST and LDH activities elevated by a high-fat/high-cholesterol diet were decreased significantly by feeding a 3% baked garlic powder diet. The serum triglyceride, total cholesterol and LDL-cholesterol levels as well as the atherogenic index and cardiac risk factor tended to decrease in the groups fed baked garlic powder than the C group, whereas the serum HDL-cholesterol level was lower in the C group and remarkably in groups fed baked garlic powder than the control group. The total cholesterol level in the liver and mesenteric adipose tissue and the triglyceride level in epididymal tissue were lower in the groups fed baked garlic powder than the C group. These results suggest that baked garlic powder reduces the serum lipid components and improves the lipid metabolism in hyperlipidemic rats induced with a high-fat/high-cholesterol diet.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1484-1490
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• 2014

In the present study, we examined the effects of a mixture of three strains, Lactobacillus plantarum CECT 7527, 7528, and 7529 (L. plantarum mixture), on body weight and lipid metabolism in Sprague-Dawley rats fed a high-fat diet. Rats were fed a high-fat diet and subjected to oral gavage with vehicle or the L. plantarum mixture ($0.6{\times}10^9$, $1.2{\times}10^9$, $2.4{\times}10^9$ colony-forming units (CFU)/day/rat, respectively) for 8 weeks. In rats fed a high-fat diet, oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture significantly reduced body weight gain as well as weights of liver and epididymal fat. Leptin levels in sera were significantly reduced by oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture. The L. plantarum mixture ($1.2{\times}10^9$ or $2.4{\times}10^9CFU/day$) also reduced the concentrations of total cholesterol and LDL-cholesterol in sera when it administered orally. Further, the L. plantarum mixture significantly reduced the atherogenic index and cardiac risk factor. In addition, oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture markedly reduced levels of total lipids, triglycerides, and total cholesterol in the liver. The results of this study indicate that the L. plantarum mixture may exhibit anti-obesity and cholesterol-lowering effects, which suggest that the L. plantarum mixture has the potential to be a probiotic in the management of obesity and hypercholesterolemia.

• Tuberculosis and Respiratory Diseases
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• v.59 no.3
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• pp.298-305
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• 2005

Background : Obstructive sleep apnea syndrome (OSAS) is believed to have multifactorial causes. The major risk factors for OSAS are obesity, narrowed upper airways, and abnormal cranial-facial structures. A genetic basis for OSAS has been also suggested by reports of families with many members affected. This study analyzed the HLA typing in patients with OSAS to determine the possible role of genetics in OSAS. Methods : Twenty-five Korean patients with OSAS (1 woman and 24 men; age range 30-66 years) were enrolled in this study. A diagnosis of OSAS was made using full-night polysomnography. The control group consisted of 200 healthy Korean people. Serologic typing of the HLA-A and B alleles was performed in all patients using a standard lymphocyte microcytotoxicity test. Analysis of the polymorphic second exons of the HLA-DRB1 gene was performed using a polymerase chain reaction-sequence specific oligonucleotide probe. Results : The allele frequency of HLA-A11 was significantly lower in patients with OSAS compared with the controls (p<0.05). The HLA-B allele frequencies in the patients and controls had a similar distribution. Analysis of the HLADRB1 gene polymorphisms showed an increased frequency of DRB1*09 in the OSA patients compared with the controls (p<0.05). When the analysis was performed after dividing the OSAS patients according to the severity of apnea, the allele frequency of HLA-DRB1*08 was significantly higher in the severe OSA patients (apnea index >45) than in the controls (p<0.05). Conclusion : This study revealed an association between OSAS and the HLA-A11 and DRB1*09 alleles as well as association between the disease severity and the HLA-DRB1*08 allele in Korean patients. These results suggest that genetics plays an important role in both the development and the disease severity of OSAS.

• Clinical and Experimental Pediatrics
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• v.51 no.5
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• pp.474-480
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• 2008

Purpose : Stress hyperglycemia is common in critically ill adult patients. It is known as a predictor of increased mortality, and intensive insulin therapy has been shown to improve the prognosis in such patients. We have investigated the relationship between early stress hyperglycemia and clinical outcomes in preterm infants. Methods : In this study, 141 preterm infants with a gestational age of less than 30 weeks were enrolled. The hyperglycemic group was defined as that having maximum glucose of more than 150 mg/dL (n=61) during the first 48 h of life, and the non-hyperglycemic group was defined as that having maximum glucose of less than 150 mg/dL (n=80). Perinatal history, severity of illness using the Clinical Risk Index for Babies (CRIB) score, clinical outcomes, and mortality of the two groups were compared. Results : There was no significant difference in the gestational age between the two groups, but the birth weight (P<0.001) was significantly lower, and the CRIB score (P<0.001) was significantly higher in the hyperglycemic group. Disseminated intravascular coagulation (P<0.001) and clinically suspected sepsis (P=0.046) were more common in the hyperglycemic group. Mortality was markedly higher in the hyperglycemic group (11.3% vs. 41.0%, P<0.001). On performing a stepwise multiple logistic regression analysis, hyperglycemia (OR 3.787; 95% CI 1.324 to 10.829), the CRIB score (OR 1.252; 95% CI 1.047 to 1.496) and birth weight (OR 0.997; 95% CI 0.994 to 1.000) was independently associated with higher mortality. Conclusion : Stress hyperglycemia within the first 48 h of life is independently related to increased morbidity and mortality in preterm infants.

• The Korean Journal of Food And Nutrition
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• v.29 no.6
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• pp.998-1007
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• 2016

The objective of this study was to investigate the effects of a lettuce (Lactuca sativa L.) extract on the inflammation of human umbilical vein endothelial cell (HUVEC) and blood lipid improvement in hypercholesterolemic mice fed a high cholesterol diet. The lettuce extract (100% ethanol extract) inhibited the expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in HUVEC treated with tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$). The lettuce extract suppressed the adhesion of THP-1 to TNF-${\alpha}$-treated HUVEC. The lettuce extract decreased the TNF-${\alpha}$-stimulated production of proinflammatory cytokine interleukin-6, interleukin-8 and chemokine monocyte chemotactic protein 1. In hypercholesterolemic mice, the lettuce extract reduced serum total cholesterol, triglyceride, and low-density lipoprotein-cholesterol level, while the lettuce extract elevated high-density lipoprotein-cholesterol level, resulting in the decrease of atherogenic index and cardiac risk factor level. These results suggested that lettuce extract can be an useful resource to show an anti-inflammatory effect and improve lipid metabolism.