• Journal of the Korean Electrochemical Society
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• v.22 no.2
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• pp.53-59
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• 2019

To examine the solution structure of electrolytes, it is very important to understand ion-ion and ion-solvent interactions. In this review, we introduce the basic principle of dielectric relaxation spectroscopy (DRS) and studies of electrolyte structure. DRS is a type of impedance method, which measures the dielectric properties of electrolytes over a high frequency domain at levels of tens of GHz. Therefore, DRS provides information on the different polar chemical species present in the electrolyte, including the type and concentration of free solvents and ion pairs with dipole moments. The information of DRS is complementary to the information of conventional analytical techniques (Infrared/Raman spectroscopy, nuclear magnetic resonance (NMR), etc.) and thus enables a broad understanding of electrolyte structure.

• Journal of the Korean Chemical Society
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• v.52 no.4
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• pp.350-355
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• 2008

• Journal of the Korean Chemical Society
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• v.45 no.3
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• pp.201-207
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• 2001

The dielectric relaxation study for aniline-dimethylsulphoxide (DMSO) and aniline-dim.ethylformamide(DMF) has been carried out using the Time domain reflectometry (TDR) technique, at different temperature and concentrations, in the frequency range of 10 MHz to 10 GHz. The dielectric parameters viz. static permittivity, relaxation time, the Kirkwood correlation factor, excess permittivity, excess inverse relaxation time and thermodynamic parameters have been obtained. The calibration method based on least squares fit method has been used. The dielectric parameters show systematic change with temperature and concentrations.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.1
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• pp.45-52
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• 2020

Hypertension often leads to cardiovascular disease and kidney disease, and hypertention is an important worldwide problem. Body mass index (BMI) has an important role for raising blood pressure. Further, hypertension can be affected by both environmental factors and genetic factors. Many single nucleotide polymorphisms have been associated with hypertension. Genome wide association study (GWAS) is a method of confirming a new locus of increasing the risk of disease, and GWAS has confirmed several single nucleotide polymorphisms (SNPs) that are associated with high blood pressure. This study analyzed the relationship between systolic blood pressure, diastolic blood pressure and SNP of the ATP2B1 gene in 994 Koreans. SNPs that showed the highest statistical significance with systolic and diastolic blood pressures were selected on the multiple linear regression analysis. One-way analysis of variance for systolic and diastolic blood pressures was performed, and multiple logistic regression analysis was performed on the risk of hypertension. The P values were two-tailed, and P<0.05 was considered significant. Four SNPs were associated with systolic blood pressure and six SNPs were associated with diastolic blood pressure. In addition, a genotype-based analysis showed significant odds ratios for the risk of hypertension in older men (adjusted OR, 5.743; 95% CI, 1.173~28.121; P=0.031). This study suggests that the ATP2B1 variants affect both the systolic and diastolic blood pressure.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.3
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• pp.97-105
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• 1999

본 논문에서는 기존의 깊이 복원 방법을 개선하기 위해서 유전 알고리즘을 이용한 새로운 스테레오 정합법을 제시하였고 다양한 영상에 적용하기 위해 영상의 영역 정보를 고려하였다. 유전 알고리즘은 자연선택과 개체군 유전학에 기반한 효율적인 탐색 기법인데, 이들의 염색체 교차와 돌연변이 같은 연산자를 정합 환경에 적합하도록 변형시켰다. 영상신호를 쉽게 다루기 위해서 2차원 염색체 구조를 사용하였으며, 스테레오 정합에 많이 사용되는 유사성과 연속성 제약 조건에 기반하여 적자를 선택하는 적응 함수를 정의하였다. 그리고 기존 유전 알고리즘의 수렴속도를 개선하기 위해서 무작위로 변이를 발생시키지 않고 휘도차를 이용하여 변이를 발생시키는 정보기반 변이 발생을 사용하였다. 실험을 통하여 본 방법은 이완처리를 포함한 정합법보다 계산 부하를 줄일 수 있었고 비교적 안정된 결과를 얻을 수 있었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1371-1377
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• 2006

Gene polymorphisms that are associated with sodium homeostasis in the body, such as $\alpha-adducin$ (ADDI, Gly460Trp), angiotensinogen (AGT, Met235Thr), and angiotensin converting enzyme (ACE, Ins/Del) may increase the risk for the development of hypertension. The purpose of this study was to elucidate the relationship between the singular and combined effects of ADD1, AGT, ACE genotypes, and blood pressure in elderly population. Moreover, we examined the interaction of sodium intake and polymorphisms of aforementioned genes and their effects on blood pressure. Among one hundred and nine female subjects, aged 60 and over (mean 75.9 yr), the major alleles for ADD1, AGT, and ACE polymorphisms in the studied population were Gly (66.1%), Thr (64.2%), Ins (83.5%), respectively. Analysis on the combined effects of genetic variation showed that subjects who were both ADD1 Trp/Trp and ACE Del/Del homozygotes had significantly higher systolic blood pressure (p=0.01). Similarly, ACE Del/Del homozygotes who had AGT Met allele had significantly higher diastolic blood pressure (p<0.001). However, in single-gene analyses, no association was found between any specific genotype and blood pressure. In subjects with low sodium intake, ADD1 Trp/Trp homozygotes had significantly higher systolic blood pressure than subjects who had ADD1 Gly allele (138 mmHg vs. 127 mmHg, p=0.03). There was no difference in blood pressure between ADD1 Trp/Trp and ADD1 Gly/Gly or Gly/Trp, in subjects with high sodium intake. In summary, this study shows that interactions between the ADD1, AGT and ACE genes influence systolic and diastolic blood pressure in elderly subjects, and dietary sodium intake can modulate the effects of ADD1 Gly460Trp polymorphisms on systolic blood pres sure.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.1
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• pp.57-63
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• 2019

Hypertension is caused by a combination of genetic and environmental factors. In advanced countries, more than 30% of adults have hypertension. Among the genetic factors affecting hypertension, there are reports from European cohort studies that variants of the MACROD2 gene are correlated with blood pressure and the hypertension status. In this study, genetic polymorphisms of the MACROD2 gene region were selected and extracted based on Korean Genome and Epidemiology data, and logistic regression analysis was then performed for the hypertensive state. Linear regression analysis was also performed for the systolic and diastolic blood pressure. As a result, 16 SNPs showed a statistically significant association with a hypertensive state, and 2 SNPs (rs16996211, rs6034240) showed statistical significance, even in blood pressure. The most significant rs16996211 had a relative risk of hypertension of 0.85 (CI: 0.76~0.95, $P=3.1{\times}10^{-3}$), as well as an association with the systolic blood pressure (beta=-0.75, P=0.024) and diastolic blood pressure (beta=-0.59, P=0.01). These results suggest that polymorphisms of the MACROD2 gene are associated with hypertension in both Caucasians and Koreans, and highlight the potential genetic correlations with the pathogenesis of hypertension.

• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.395-401
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• 2008

Genetic diversity and differentiation within or among nine populations of introduced fish, largemouth bass Micropterus salmoides were assessed by AFLP. The AFLP analysis using three primer combinations generated 299.2. AFLP bands and percentage of polymorphic bands were similar in those nine populations, ranging 14.1 to 21%. Heterozygosity and genetic diversity within or among populations were quite low for all of these populations with average values ranging from 0.054 to 0.067 and from 0.069 to 0.085, respectively. Analyses of pairwise distance and genetic similarity among nine populations of Micropterus salmoides also revealed the similar results with low genetic differentiation one another. Although pairwise Fst values were low, they were indicated a clear distinct genetic differentiation among the nine populations. These results indicate that very small population of the largemouth bass was first introduced to Paldang reservoir and they are widely spread at most of aquatic habitats in Korea.

• Advances in pediatric surgery
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• v.8 no.1
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• pp.41-47
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• 2002

Abnormal distribution of the enteric nerves such as adrenergic, cholinergic and peptidergic nerves may cause the functional obstruction in Hirschsprung's disease (HD). Although the sustained contraction of the aganglionic segment is the main pathophysiology of HD, the etiology and pathogenesis is not thoroughly understood, With the recent progress of molecular biology and genetics,a more detailed approach to the pathogenesis of the HD can be undertaken. In this review, the roles of the nitric oxide, nitric oxide synthase and interstitial cells of Cajal on smooth muscle relaxation, the effects of extracellular matrix, cell adhesion molecules, neurotrophic factors on the migration and maturation of the neural crest cells are described. In the section of genetic factors, familial occurrences, association of chromosomal abnormalities, RET gene, glial cell line-derived neurotrophic factor gene, endothelin-3 gene and endothelin-B receptor gene and their r elationships to HD is briefly reviewed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.1
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• pp.8-13
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• 1990

The microscopic relaxation parameters for the single crystal were measured by using thermally stimulated depolarization (TSD). Initial rise method, various heating rate method and total glow peak method were used for the determination of the activation energy and Debye relaxation time from TSD glow curves. Activation energy, pre-exponential factor and relaxation time for impurity-vacancy dipole reorientation were 0.55eV, 1.97$\times$10 super(-12) sec and 12.19sec in average, respectively. Dielectric dissipation factor for the crystal was calculated from the measured TSD glow curve, its value being about 3$\times$10 super(-2).