• Applied Biological Chemistry
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• v.47 no.3
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• pp.344-350
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• 2004

This study was conducted to develop and assess the applicability of mixed-bed ion exchange resin capsules for water quality monitoring in small agricultural watershed. Recoveries of resin capsules for inorganic N and P ranged from 96 to 102%. The net activation energies and pseudo-thermodynamic parameters, such as ${\Delta}G^{o\ddag},\;{\Delta}H^{o\ddag},\;and\;{\Delta}S^{o\ddag}$ for ion adsorption by resin capsules, exhibited relatively low values, indicating the process might be governed by chemical reactions such as diffusion. However, those values increased with temperature coinciding with the theory. The reaction reached pseudo-equilibrium within 24 hours for $NH_4-N\;and\;NO_3-N$, and only 8 hours for $PO_4-P$, respectively. The selectivity of resin capsules were in the order of $NO_3\;^-\;>\;NH_4\;^+\;>\;PO_4\;^{3-}$, coinciding with that of encapsulated Amberlite IRN-150 resin. At the initial state of equilibrium, the resin adsorption quantity was linearly proportional to the mass of ions in the streams, but the rate of movement leveled off, following Langmuir-type sorption isotherm. The overall results demonstrated that the resin capsule system was suitable for water quality monitoring in small agricultural watershed, judging from the reaction mechanism(s) of the resin capsule and the significance of model in field calibration.

• Tuberculosis and Respiratory Diseases
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• v.54 no.5
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• pp.485-494
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• 2003

Background : Most previous studies regarding the role of GSTMl and GSTT1 on lung cancer risk have been focused mainly on male smokers. However, epidemiological characteristics, histologic types and risk factors are different in female and male lung cancers, we investigated the association between these genotypes and lung cancer risk in males and females separately. Materials and Methods : The study population consisted of 253 lung cancer (153 males and 100 females) and 243 controls (140 males and 103 females). GSTM1 and GSTT1 genotypes were determined by a multiplex PCR. Results : In the male population, neither GSTM1 nor GSTT1 null genotype showed significant difference between cases and controls. In the female population, the frequencies of GSTM1 null genotype showed no significant difference between cases and controls. However, the frequencies of GSTT1 null genotype was significantly higher in cases (70.3%) than controls (55.3%, odds ratio (OR)=2.18; 95% confidence interval (CI=l.21-3.93). When the female population was stratified by age and smoking status, the ORs for GSTT1 null genotype were significantly higher in subgroups of ${\leq}60$ years (OR=4.82; 95% CI=l.61-14.4) and never-smokers (OR=4.29; 95% CI=1.94-9.48) but not in subgroups of >60 years or smokers. When stratifying the female never-smokers by age, the ORs for GSTT1 null genotype were significantly higher in both age groups of ${\leq}60$ years (OR=7.64; 95% CI=2.00-29.2) and >60 years (OR=2.89; 95% CI=1.05-7.94). Conclusion : We found that GSTT1 null genotype was associated with an increased risk of lung cancer in Korean female never-smokers. This result suggests that GSTT1 null genotype could be used as a biomarker for genetic susceptibility to lung cancer in Korean female never-smokers.

• (The)Study of the Eastern Classic
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• no.71
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• pp.99-128
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• 2018

Zhōuyì周易 is intended to explain the affairs of human beings by observing the images and works of all things in the universe, abstracting them into the $b{\bar{a}}gu{\grave{a}}$八卦, calculating the process and inducing the outcome by the method of stalk divination, in which this paper finds the origin of natural scientific thought of Zhōuyì. The way of Zhōuyì's thought on the natural science is distinguished from that of the Western's. In the West, people dismantled the objects into the parts until they reached the atom and analyzed them by the principle of causality to draw an axiomatic truth. In the meantime Zhōuyì observed and studied the dynamic functions and changes of all things for the convergence of the whole. While the way of Zhōuyì's thinking could have not contributed to the development of modern scientific development, that of the West overwhelmed Asian development passing through the period of enlightenment during 16-17 century. This paper tries to articulate the points where Zhōuyì can share its theory with the contemporary science by finding the traces of scientific thoughts in Zhōuyì. It encounters its ground from the methodology of natural science and scientific statements proposed by Zhōuyì. The essential concepts of Zhōuyì are induced from all things in nature. This can be considered as the idea of '法自然'(emulating the patterns and examples from nature). Also they observed the images and changes seen by the habits of animals, plants and human beings to sense and perceive their laws. These are regarded as the methodology of natural science in Zhōuyì. As a book of divination, the way of stalk divination is designed to calculate the future by using the system of 'numbers'. 'tàijí太極', ' yīnyáng陰陽', 'four symbols四象', '$b{\bar{a}}gu{\grave{a}}$八卦' and 'wǔxíng五行' are the essential concepts of Zhōuyì to represents the dynamic phenomena and changes of the natural order. Among them '$b{\bar{a}}gu{\grave{a}}$八卦' is a presentment to explain the structure of the world not by the individual analysis of things but by the unification of the whole through the contradictions and interchanges among them to reach the new orders. As of now, the studies of Zhōuyì in Korea have focused on the traditional perspectives, such as political and ethical philosophy. Some of recent studies, having interpreted Zhōuyì with scientific inclination have generated controversy 'Can Zhōuyì be a science?', for which scholars have hard time to reach the agreement. This paper tries to find the headwaters of the contemporary natural science by elaborating the methodology of natural science stated in Zhōuyì.