• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.458-468
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• 2019

This research attempted to estimate monthly sales of food and beverage at the passenger terminal of Incheon int'l airport from June of 2015 to December 2020. This paper used ARIMA-Intervention model which can estimate the change of the sales amount suggesting the predicted monthly food and beverage sales revenue. The intervention variable was travel-ban policy against south Korea from P.R. China since July 2016 to December 2017 due to THAAD in south Korea. According to ARIMA, it was found normal predicted sales amount showed the slow growth increase rate until 2020 due to the effect of intervened variable. However, the monthly food sales in July and August 2019 was 20.3 and 21.2 billion KRW respectively. Each amount would increase even more in 2020 and the amount would increase to 21.4 and 22.1 billion KRW. The sales amount in 2019 would be 7.7 and 8.1 billion KRW and climb up 7.9 and 8.2 billion KRW in 2020. It was expected LCC passengers tend to spend more money for F&B at airport due to no meal or drink service of LCC or the paid-in meal and beverage service of LCC. The growth of sales of food and beverate will be accompanied with the growth of LCC according to estimated data.

• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.596-606
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• 2019

N-acyl-homoserine lactone quorum sensing (AHL-QS) has been shown to regulate many physiological behaviors in Serratia marcescens MG1. In the current study, the effects of AHL-QS on the biosynthesis of acid and neutral products by S. marcescens MG1 and its isogenic ${\Delta}swrI$ with or without supplementing exogenous N-hexanoyl-L-homoserine lactone ($C_6-HSL$) were systematically investigated. The results showed that swrI disruption resulted in rapid pH drops from 7.0 to 4.8, which could be restored to wild type by supplementing $C_6-HSL$. Furthermore, fermentation product analysis indicated that ${\Delta}swrI$ could lead to obvious accumulation for acidogenesis products such as lactic acid and succinic acid, especially excess acetic acid (2.27 g/l) produced at the early stage of fermentation, whereas solventogenesis products by ${\Delta}swrI$ appeared to noticeably decrease by an approximate 30% for acetoin during 32-48 h and by an approximate 20% for 2,3-butanediol during 24-40 h, when compared to those by wild type. Interestingly, the excess acetic acid produced could be removed in an AHL-QS-independent manner. Subsequently, quantitative real-time PCR was used to determine the mRNA expression levels of genes responsible for acidogenesis and solventogenesis and showed consistent results with those of product synthesis. Finally, by close examination of promoter regions of the analyzed genes, four putative luxI box-like motifs were found upstream of genes encoding acetyl-CoA synthase, lactate dehydrogenase, ${\alpha}$-acetolactate decarboxylase, and Lys-like regulator. The information from this study provides a novel insight into the roles played by AHL-QS in switching from acidogenesis to solventogenesis in S. marcescens MG1.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.1
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• pp.64-81
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• 2019

The purpose of this study is to analyze elementary science gifted students' characteristics of the thinking in the problem solving process through a MEA(Model Eliciting Activity)activity. The subjects of this study are 40 elementary science gifted students who passed the first screen for the admission to the science gifted education institute in P university in 2018. The MEA activity was 'Coffee cup challenge', which is to find the best way to place cup side and bottom to save paper in a given material. Three drawings from each student and explanations of each drawing through out the design process were collected as the main data source. The data were analyzed by statistically (correlation coefficient) and qualitatively to find the relationship between; 1) the intuitive thinking and visual representation and 2) analytical thinking ability and communication skills that reflect MEA activities. In conclusion, first, intuitive thinking plays an important role in the ability of visual representation through pictures and the whole problem solving process. Second, the analytical thinking and elaboration process which are reflected through reflection on the arrangement of the drawings have a great influence on the communication skills. Therefore, this study investigated that MEA activities are useful activities to stimulate both intuitive and analytical thinking in elementary science gifted students, and to develop communication ability, by organizing their own ideas and providing learning opportunities for various solutions.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.125-134
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• 2019

The purpose of this study is to explore the direction of decision support for senior citizens living alone by identifying the level of self-determination and desire for decision support. The survey was conducted on 300 elderly people living alone in five districts of Seoul. The analysis results are as follows: First, it has been shown that elderly living alone have thought that it is most important to reflect their decisions when deciding where to live. Second, respondents highly recognized that the need for support decision making as the age group grew. Third, it was found that the factors affecting the perception of the need to support decision-making by senior citizens living alone were age, trust in family and recognition of importance in decision-making. The study suggested the need for a specific, institutionalized system to support decision making for elderly living alone.

• Journal of Environmental Health Sciences
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• v.45 no.1
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• pp.30-41
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• 2019

Objectives: The effects of particulate matter and ozone on health are being reported in a number of studies. These effects are likely to be stronger on the elderly population, but studies in this regard are scarce. The purpose of this study was to examine the effects of particulate matter ${\leq}2.5{\mu}m$ and ozone on the acute health status of the elderly population. Methods: In order to analyze the health status of the elderly population, the NHIS-Senior Cohort data was used. In this study of people 60 years or older in Seoul, the number of outpatient visits and ER visits between 2002 and 2013 were calculated. Each disorder and the lag effect were analyzed separately. Particulate matter and ozone were analyzed using both the single exposure model and the adjusted multi-exposure model. Results: In the single exposure analysis with PM2.5 as the exposure variable, with each increase of $10{\mu}g/m^3$, the number of outpatient visits increased by 1.0081 times, vascular disease 1.0065 times, chronic pulmonary disease 1.0086 times, and diabetes 1.0055 times. In the multi-exposure model adjusting for ozone, the number of outpatient visits increased by 1.0066 times. There was a one-day lag effect and 1.0066 times increase between PM2.5 and ER visits in the multi-exposure model and 1.0057 times when adjusted for ozone (p value <0.10). There was a one-day lag effect in all multi-exposure models with ozone as the main variable, and when the particulate matter was adjusted, there was a one-day delay and 1.0143 times increase in ER visits. Conclusions: In our study, an increase in the number of outpatient and ER visits in the elderly population in accordance with the increase in PM2.5 and ozone was found. The association found in our study could also produce a socioeconomic burden. Future studies need to be performed in regards to younger populations and other air pollutants.

• Journal of the Korea Convergence Society
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• v.12 no.4
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• pp.77-86
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• 2021

This study explored the role of perceived stress in Korean high school students' suicidal thought. In so doing, we also investigated the mediating role of high school students' internet use time and amount of drinking alcohol. For this, 2019 Korean adolescent health behavior survey was used. Complex design multivariage logistic regression analysis revealed that high school students' perceived stresss(OR:5.607, 95%CI:5.077-6.191) and amount of drinking(ranging from OR:1.412, 95%CI:1.159-1.720 to OR:2.325, 95%CI:1.928-2.803) played a significant role in their suicidal thoughts. Internet use time and amount of alcohol consumed were found to play a mediating role. Implications of the results are discussed. Therefore, since internet use mediated suicidal thinking among adolescents, it is necessary to develop a intervention program or message for them.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.359-369
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• 2021

This study aims to investigate pre-service primary English teachers' perceptions of multicultural education. For this study, the researchers surveyed 63 pre-service teachers at a national university of education using an online survey. A quantitative method is used in order to collect and analyze data. The results revealed the following: First, pre-service primary English teachers stand at a considerably high level in their overall understanding of elementary students and clearly recognize the necessity of multicultural education in school. Second, concerning the difference that the personal variables of gender, grade, and major make in the subjects' perception of English education based on multicultural education, grade showed no statistically significant difference, but gender and major are responsible for a slight difference. Third, an analysis was made of the correlation between the subjects having or not having received multicultural education and the personal variables of gender, grade, and major, yielding the following results: Gaining or not gaining multicultural education does not correlate with gender, but does significantly with grade and major.

• Biomedical Science Letters
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• v.26 no.4
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• pp.344-350
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• 2020

Asthma is a chronic disease and occurs in airway in the lung. The cause of the disease has not been identified, it is assumed that both genetic and environmental risk factors play an important role in the development of asthma. Interleukin (IL)-12 is a cytokine regulating T-cell and NK cell. In this study, we analyzed the genetic polymorphisms of IL-12 receptor genes (IL-12Rβ1 and IL-12Rβ2) in asthma patients and normal individuals in a Korean population. We analyzed single nucleotide polymorphisms (SNPs) in IL-12Rβ1 and IL-12Rβ2 using the genotype data of 193 asthma cases and 3,228 healthy controls from the Korea Association REsource for their correlation with asthma case. IL-12Rβ1 and IL-12Rβ2 genes showed statistically significant polymorphism association with asthma case. As a results, 16 SNPs from IL-12Rβ1 and IL-12Rβ2 genes showed statistically significant association with asthma. Among them, rs375947 SNP in IL-12Rβ1 showed the greatest statistical correlation with asthma (P-value = 0.028, Odds Ratio = 1.27, 95% Confidence Interval = 1.03~1.57). The groups with minor allele of IL-12Rβ1 and IL-12Rβ2 showed increased risk of asthma. The genotype-based mRNA expression analysis showed that the group of minor allele of IL-12Rβ1 showed decreased mRNA expression. Decreased IL-12Rβ1 expression causes decreased IL-12 signaling, and this affects developing asthma. In conclusion, the SNPs in IL-12Rβ1 and IL-12Rβ2 may contribute to development of asthma in a Korean population.

• Journal of Korean Academy of Oral Health
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• v.41 no.4
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• pp.290-295
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• 2017

Objectives: Dental plaque emits red fluorescence under a visible blue light near the ultra-violet end of the light spectrum. The fluorescence characteristics of each microorganism have been reported in several studies. The aim of this study was to evaluate changes in red fluorescence of oral microorganisms that is affected by blood in the culture media. Methods: The gram-positive Actinomyces naeslundii (AN, KCTC 5525) and Lactobacillus casei (LC, KCTC 3109) and gram negative Prevotella intermedia (PI, KCTC 3692) that are known to emit red fluorescence were used in this study. Each bacterium was activated in broth and cultivated in different agar media at $37^{\circ}C$ for 7 days. Tryptic soy agar with hemin and vitamin $K_3$ (TSA), TSA with sheep blood (TSAB), basal medium mucin (BMM) medium, and BMM with sheep blood (BMMB) were used in this study. Fluorescence due to bacterial growth was observed under 405-nm wavelength blue light using the quantitative light-induced fluorescence-digital (QLF-D) device. The red, green, and blue fluorescence values of colonies were obtained using image-analysis software and the red to green ratio (R/G value) and red to total RGB ratio (R/RGB value) were calculated for quantitative comparison. Results: The QLF-D images of the AN, LC, and PI colonies showed red fluorescence in all media, but the fluorescence of all bacteria was reduced in TSA and BMM media, compared with in TSAB and BMMB media. Both the R/G and the R/RGB values of all bacteria were significantly reduced in growth media without blood (P<0.001). Conclusions: Based on this in vitro study, it can be concluded that red fluorescence of oral bacteria can be affected by growth components, especially blood. Blood-containing medium could be a significant factor influencing red fluorescence of oral bacteria. It can be further hypothesized that bleeding in the oral cavity can increase the red fluorescence of dental plaque.

• The Korea Journal of Herbology
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• v.32 no.5
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• pp.47-55
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• 2017

Objectives : Obesity is caused by the excess accumulation of fat in the body due to energy imbalance, and it causes various diseases. The aim of this study was to investigate an anti-obesity efficacy and an antioxidant activity of water from herbal mixture extract (SM17). Methods : The antioxidant activities were evaluated through radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals. To evaluated anti-obesity effect of SM17, we used a high fat diet fed mouse model. The SM17 (150 mg/kg body weight/day, p.o.) was treated every day for 6 weeks to C57BL/6 mice. Body weight and food intake were measured every day. The changes of reactive oxygen species (ROS), alanine aminotransferanse (ALT), aspartate aminotransferase (AST), triglycerids (TG) and total cholesterol (TC) in serum were analyzed after experiment. Also, expression of lipid metabolism related proteins were investigated by western blot analysis. Results : It was effective in antioxidant measurements, SM17 administration inhibited the biomarkers of lipid metaboism in serum and tissues. The administration of SM17 showed a significant reduction of body and tissue weight. Morever, it decreased ROS, ALT, AST, TG and TC in serum, compared with those of the obese mice. Adipogenesis-related protein expressions increased in obese mice compared to normal mice. However, SM17 group exhibited the down-expression of these proteins. Conclusion : A SM17 aqueous extract has a great effect on the stimulation (AMPK) activation, and may have a benefit to reduce a fatty acid metabolism through inhibition of lipid accumulation.