• Journal of Microbiology and Biotechnology
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• v.33 no.11
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• pp.1506-1512
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• 2023

Quantitative analysis of adenosine triphosphate (ATP) has been widely used as a diagnostic tool in the food and medical industries. Particularly, the pathogenesis of a few diseases including inflammatory bowel disease (IBD) is closely related to high ATP concentrations. A bioluminescent D-luciferin/luciferase system, which includes a luciferase (FLuc) from the firefly Photinus pyralis as a key component, is the most commonly used method for the detection and quantification of ATP. Here, instead of isolating FLuc produced in recombinant Escherichia coli, we aimed to develop a whole-cell biocatalyst system that does not require extraction and purification of FLuc. To this end, the gene coding for FLuc was introduced into the genome of probiotic Saccharomyces boulardii using the CRISPR/Cas9-based genome editing system. The linear relationship (r² = 0.9561) between ATP levels and bioluminescence generated from the engineered S. boulardii expressing FLuc was observed in vitro. To explore the feasibility of using the engineered S. boulardii expressing FLuc as a whole-cell biosensor to detect inflammation biomarker (i.e., ATP) in the gut, a colitis mouse model was established using dextran sodium sulfate as a colitogenic compound. Our findings demonstrated that the whole-cell biosensor can detect elevated ATP levels during gut inflammation in mice. Therefore, the simple and powerful method developed herein could be applied for non-invasive IBD diagnosis.

• Tunnel and Underground Space
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• v.13 no.5
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• pp.331-343
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• 2003

Though the Grouting has been in use for a long time, it is still regarded as an technique rather than engineering. The study of ground improvement by grouting is rare especially in jointed rock mass. In this study, biaxial compression tests were performed in the jointed rock mass models with .ough surfBce joints assembled with blocks before and after grouting. The load-deformation curves of the jointed rock masses showed a non-linear relationship before grouting but showed a relatively linear deformaion behavior after grouting. Improvement ratio (deformation modulus after grouting/deformation modulus before grouting) decreased with increasing joint spacing and lateral stress. Improvement ratio decreased exponentially with increasing deformation modulus of the rock mass model before grouting. Three-dimensional FDM analysis was performed to a highway tunnel case using experimental data of grouted rock. The convergence of the tunnel predicted after grouting by the numerical modelling coincided with those attained from the field measurement.

• Journal of the Korean GEO-environmental Society
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• v.11 no.1
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• pp.19-26
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• 2010

The batch experiments and response surface methodology (RSM) have been applied to the investigation of the cadmium (Cd) adsorption by coal fly ash (CFA). CFA having maximum Cd removal mass of 8.51 mg/g were calculated from Langmuir model. Cd removal reaction with different initial pH ranged from 4 to 9. When the initial pH was higher, Cd was removed more by adsorption and precipitation. These results suggest that the lower pH cause an increase of $H^+$ ion concentration which competed with Cd ions for exchange sites in CFA. Also, The Cd adsorption was mathematically described as a function of parameters initial Cd concentration ($X_1$), initial pH ($X_2$), and initial CFA mass ($X_3$) being modeled by use of the Box-Behnken methods. Empirical models were developed to describe relationship between the experimental variables and response. Statistical analysis indicates that tree factors ($X_1$, $X_2$, and $X_3$) on the linear term (main effects), and tree factors ($X_1X_2$, $X_1X_3$, and $X_2X_3$) on the non-linear term (Interaction effect; cross-product) had significant effects, respectively. In this case, the value of the adjusted determination coefficient (adjusted $R^2=0.9280$) was closed to 1, showing a high significance of the model. Statistical results showed the order of Cd removal at experimental factors to be initial initial pH > initial Cd concentration > initial CFA mass.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.182-189
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• 2021

A study was conducted to identify the general characteristics of some dental hygiene students and to identify the factors affecting the achievement goal orientation and academic achievement according to the teaching method selection for increase the academic achievement of the subject in the special education environment caused by the COVID-19. In the second semester of 2020, a survey was conducted on 122 students of G University's dental hygiene department located in Gwangju, and the general characteristics and achievement goal orientation were surveyed. Academic achievement has used the midterm and final exam scores and the collected data were analyzed using Kruskal-Wallis test, Mann-Whitney U test, Pearson's correlation test, Multiple Linear Regrission. According to the general characteristics, there was a significant difference in subject understanding, subject interest, and subject satisfaction, and learning satisfaction showed a strong correlation with the completion goal tendency. There was a significant difference in academic achievement according to the class choice, and the factor that influenced the academic achievement was the case that the teaching method was chosen face-to-face. Therefore, in order to improve learners' academic achievement, it is necessary to increase the proportion of face-to-face classes and to establish an effective lesson plan that can increase the degree of subject understanding, subject interest, and subject satisfaction.

• Tuberculosis and Respiratory Diseases
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• v.72 no.2
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• pp.163-168
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• 2012

Background: Cigarette smoke induced release of iron could alter iron metabolism in the lungs of chronic smokers and contribute to the increase in the total oxidative burden on the lungs of smokers. In previous studies, ferritin levels of bronchoalveolar lavage fluid in smokers were elevated. The aim of the present study was to investigate the relationship between serum ferritin concentration, smoking and lung function in Korean people. Methods: This study was based on the data acquired in the second year (2008) of the Forth National Health and Nutrition Examination Survey that was conducted from 2007 to 2009. The analysis included 2,244 subjects who were older than 20 years and had complete data from both lung function test and serum ferritin concentration. Among participants, 1,076 were male and 1,168 were female. Results: Mean serum ferritin concentrations in males were $120.3{\pm}80.1{\mu}g/L$ and $47.9{\pm}39.8{\mu}g/L$ in females. There were no differences in serum ferritin concentrations between non-smokers and smokers after adjusting for age, body mass index, and amounts of alcohol. Serum ferritin concentrations were associated with smoking amounts by simple linear regression but not associated with smoking amounts after adjustment with age, body mass index, and amounts of alcohol in both males and females. Lung function was not associated with serum ferritin concentrations. Conclusion: Our data suggested that serum ferritin concentrations are not related with smoking and lung function.

• The Journal of Internal Korean Medicine
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• v.28 no.4
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• pp.830-837
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• 2007

Background and purpose : Stroke is one of the most deadly diseases and a leading cause of disability. Lipids confer an increased risk for cardiovascular morbidity and mortality. In spite of many studies on the relationship between stroke and lipids, their relationship is not clear. This study was undertaken to determine whether lipids were associated with stroke. Method : We compared the components of blood lipids between stroke patients group (n=217,Cases), non-stroke control group (n=160, Controls) and healthy control group without hypertension, diabetes mellitus, ischemic heart disease, or hyperlipidemia (n=140, Normals). These data were statically analyzed by general linear models and binary logistic regression analysis to get each adjusted odds ratio. Result : The results were as follows. The blood levels of total cholesterol (T-Chol), triglyceride (TG) and low density lipoprotein cholesterol (LDL-Chol) were significantly higher in patients of ischemic stroke, while the blood levels of T-Chol and LDL-Chol were significantly lower, and the blood levels of TG significantly higher in patients of hemorrhagic stroke. The blood level of high density lipoprotein cholesterol (HDL-Chol) was significantly lower in all cases. Conclusion : These results suggest that high TG and low HDL-Chol may be risk factors of hemorrhagic stroke and ischemic stroke, high T-Chol and LDL-Chol may be risk factors of ischemic stroke, and low T-Chol and LDL-Chol may be risk factors of hemorrhagic stroke in Koreans.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.2
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• pp.207-217
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• 2016

Permeability can not be expressed as a function of porosity alone, it depends on the porosity, pore size and distribution, and tortuosity of pore channels in concrete. There has been considerable interest in the relationship between microstructure and transport in cementitious materials, however, it is very rare to deal with the theoretical study on gas permeability coefficient in connection with carbonation of concrete and the effect of volumetric fraction of cement paste or aggregate on the permeability coefficient. The majority of these researches have not dealt with this issue combined with carbonation of concrete, although carbonation can significantly impact on the permeability coefficient of concrete. In this study, fundamental approach to compute gas permeability of (non)carbonated concrete is suggested. For several compositions of cement pastes, the gas permeability coefficient was calculated with the analytical formulation, followed by a microstructure-based model. For carbonated concrete, reduced porosity was calculated and this was used for calculating the gas permeability coefficeint. As the result of calculation of gas permeability for carbonated concrete, carbonation leaded to the significant reduction of gas permeability coefficient and this was obvious for concrete with high w/c ratio. Meanwhile, the relationship between gas permeability and water permeability has a linear function for cement paste based on Klinkenberg effect, however, which is not effective for concrete. For the evidence of the modeling, YOON's test was accomplished and these results were compared to each other.

• Journal of dental hygiene science
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• v.14 no.3
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• pp.371-378
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• 2014

This study aims to evaluate the influence of vitamin and mineral supplement intake, and degree of calcium and phosphorus intake on occurrence of dental caries in primary teeth. Research data was derived from the Fourth Korean National Health and Nutrition Examination Survey (KNHANES) and 1,139 Korean children of 3 to 6 years were selected as subject for this study. The dft index, nutrition factor including vitamin or mineral supplement intake and degree of intake for calcium (Ca) and phosphorus (P) were identified. Chi-square test was performed to assess the difference in socioeconomic status, oral health behavior and nutrition factor, including vitamin or mineral supplement intake and degree of intake for Ca and P. Linear regression analysis was performed to identify the relationship between the dft index and the related variables. As a result, the dft index was increased with the age. Significant differences in Ca intake was examined according to the sex, and P intake was different according to the sex in 3-year-old group. Among the 4-year-old children, the vitamin and mineral supplement takers had 1.206 less dft index than the non-takers. In conclusion, intake of Ca, P and vitamin/mineral supplement was not a pivotal factor to influence the incidence of primary teeth caries. However, significantly low dft index was observed from 4-year-old group who intake vitamin or mineral.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.267-271
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• 1991

The chemical and organoleptic properties of dongchimi studied for their changes during fermentation at $4{\sim}35^{\circ}C$ in 7% NaCl solution with seasonings. It was found that pH decrease showed three variation points in its slope at about pH 5.2, 4.7 and 4.1 during fermentation. A negative linear relationship between total acidity and logarithmic value of pH was obtained. The slope of the relationship curve was increased as the fermentation temperature increased. The reducing sugar was increased until pH reached$4.0{\sim}4.2$ followed by a small decrease and its amount was lowered as the temperature increased from $4\;to\;25^{\circ}C$ The major nonvolatile organic acids were lactic and citric acids. The increase in lactic acid were more marked at $25^{\circ}C$ than at $4^{\circ}C$. As fermentation proceeded the fresh radish odor significantly decreased while sourness and yeast-moldy odor increased. The crispness of the radish decreased slightly during fermentation.

• Korean Journal of Legislative Studies
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• v.24 no.1
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• pp.203-239
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• 2018

Responsible government can be achieved when social cleavages are institutionalized via political competition and social interests are represented by responsible parties. This paper aims to investigate the factors that determine welfare expenditures in Korean local governments by analyzing partisanship and political competition factors simultaneously in the same model. This paper also argues that the relationship between the political factors and welfare expenditures in local governments is not linearly increasing as the previous studies claim. This paper examines the welfare expenditures in Korean municipality-level local governments in 2007, 2011, and 2015. The primary findings are: 1) the partisanship of the head of local government and the party distribution of local assembly members have meaningful effect on the welfare expenditures and the divided governments do not show significantly different effect on welfare expenditures from unified governments, which is contrary to the extant studies, 2) the partisan effects of the head and the local assembly vary according to the levels of municipalities (Gu, Gun, and city), mainly due to the difference in types of revenues and expenditures and 3) the relationship between seats shares of progressive parties in local assembly and the welfare expenditure is not linearly increasing one. The effect of seats shares of progressive parties dramatically begins to increase when the seats shares are in 40%-60%. With these findings, this paper highlights the conservative nature of head of local governments with Hannara party (or Saenuri Party), the conservative leaning of independent candidates, and the conservative orientation of local assemblies in the regions dominated by Democratic Party (and its equivalents).