• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.378-384
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• 2012

In aquatic invertebrates, particularly marine gastropods, organotin compounds induce irreversible sexual abnormality in females, which is termed imposex, at very low concentrations. Organotin compounds are agonists for nuclear receptors such as RXRs and $PPAR{\gamma}$. However, the imposex phenomenon has not been reported to act as an antagonist on estrogen receptors in other species, including vertebrates and invertebrates. In order to gain insights into the antagonistic activity of organotin compounds on estrogen receptors (ERs), we examined the inhibitive effect of these compounds on estradiol-dependent ${\beta}$-galactosidase activity using the yeast two-hybrid detection system consisting of a combination of the human estrogen receptor ($hER{\beta}$) ligand-binding domain and the co-activator steroid receptor co-activator-1 (SRC1). Tributyltin-hydroxide (TBT-OH) and triphenyltin-chlorine (TPT-Cl) exhibited an inhibitive effect on $E_2$-dependent transcriptional activity, similar to antagonistic chemicals such as 4-hydroxytamoxifen (OHT) or ICI 182,780, at a very low concentration of $10^{-14}$ M TBT or $10^{-10}$ M TPT, respectively. The yeast growth and transcriptional activity with transcriptional factor GAL4 did not exhibit any effect at the tested concentration of TBT or TPT. Moreover, the yeast two-hybrid system using the interaction between p53 and the T antigen of SV40 large did not describe any effect at the tested concentration of OHT or ICI 182,780. However, the interaction between p53 and T antigen was inhibited at a TBT or TPT concentration of $10^{-9}$ M, respectively. These results indicate that TBT and TPT act as inhibitors of ER-dependent reporter gene transcriptional activation and of the interaction between $hER{\beta}$ LBD and the co-activator SRC1 in the yeast two-hybrid system. Consequently, our data could partly explain the occurrence of organotin compound-induced imposex on the endocrine system of mammals, including humans.

• Molecules and Cells
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• v.40 no.3
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• pp.202-210
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• 2017

The nonstructural protein 5A (NS5A) encoded by the human hepatitis C virus (HCV) RNA genome is a multifunctional phosphoprotein. To analyse the influence of NS5A on apoptosis, we established an Hep-NS5A cell line (HepG2 cells that stably express NS5A) and induced apoptosis using tumour necrosis factor $(TNF)-{\alpha}$. We utilised the MTT assay to detect cell viability, real-time quantitative polymerase chain reaction and Western blot to analyse gene and protein expression, and a luciferase reporter gene experiment to investigate the targeted regulatory relationship. Chromatin immunoprecipitation was used to identify the combination of $NF-{\kappa}B$ and miR-503. We found that overexpression of NS5A inhibited $TNF-{\alpha}$-induced hepatocellular apoptosis via regulating miR-503 expression. The cell viability of the $TNF-{\alpha}$ induced Hep-mock cells was significantly less than the viability of the $TNF-{\alpha}$ induced Hep-NS5A cells, which demonstrates that NS5A inhibited $TNF-{\alpha}$-induced HepG2 cell apoptosis. Under $TNF-{\alpha}$ treatment, miR-503 expression was decreased and cell viability and B-cell lymphoma 2 (bcl-2) expression were increased in the Hep-NS5A cells. Moreover, the luciferase reporter gene experiment verified that bcl-2 was a direct target of miR-503, NS5A inhibited $TNF{\alpha}$-induced $NF-{\kappa}B$ activation and $NF-{\kappa}B$ regulated miR-503 transcription by combining with the miR-503 promoter. After the Hep-NS5A cells were transfected with miR-503 mimics, the data indicated that the mimics could reverse $TNF-{\alpha}$-induced cell apoptosis and blc-2 expression. Collectively, our findings suggest a possible molecular mechanism that may contribute to HCV treatment in which NS5A inhibits $NF-{\kappa}B$ activation to decrease miR-503 expression and increase bcl-2 expression, which leads to a decrease in hepatocellular apoptosis.

• Journal of Korean Home Economics Education Association
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• v.32 no.1
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• pp.127-143
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• 2020

The purpose of this study is to develop the clothing safety teaching/learning plan in Home Economics based on the health belief model and to examine the effects of the course using the developed teaching/learning plan on the health belief. Based on ADDIE model, 6 clothing safety teaching/learning plans were developed by applying the health belief model. They consisted of three learning factors of 'harmful substances that can be exposed during the production, wear, wash, and storage of clothes and textile products', 'environment friendly fibers' and 'natural detergents'. Then they were implemented on 7 classes in middle school located in Gyeonggi-do Province from August 20 to September 7 in 2018. The health beliefs data collected before and after the course were analyzed with paired t-test with SPSS/win. As a result, the perceived threat(combination of perceived severity and perceived susceptibility), the perceived benefit, and the self-efficacy were significantly improved. And the perceived barrier was significantly reduced. In conclusion, the home economics clothing safety education course using the health belief model was meaningful as the safety education to enable middle school students to practice safe clothing life from harmful substances. The results of this study are expected to be helpful for activating safety education in home economics.

• Journal for History of Mathematics
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• v.18 no.4
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• pp.85-100
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• 2005

In recent papers (Pak et al., Pak and Kim), it was suggested to positively use the history of mathematics for the education of mathematics and discussed the determining problem of the order of instruction in mathematics. There are three kinds of order of instruction - historical order, theoretical organization, lecturing organization. Lecturing organization order is a combination of historical order and theoretical organization order. It basically depends on his or her own value of education of each teacher. The present paper considers a concrete problem determining the order of instruction for the concept of angle. Since the concept of angle is defined in relation to figures, we have to solve the determining problem of the order of instruction for the concept of figure. In order to do this, we first investigate a historical order of the concept of figure by reviewing it in the history of mathematics. And then we introduce a theoretical organization order of the concept of figure. From these basic data we establish a lecturing organization order of the concept of figure from the viewpoint of problem-solving. According to this order we finally develop the concept of angle and a related global property which leads to the so-called Gauss-Bonnet theorem.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.183-194
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• 2021

In this study, the conversion factor for 2020 is estimated based on an outpatient and inpatient conversion factor separation model developed from SGR and AR by using actual medical expense data. In addition, a policy plan is proposed to calculate the values of single and multiple conversion factors for each type of medical expense, and to effectively use the conversion factor separation model as one of the means to establish a medical delivery system. The major results are as follows. First, at r=0.1, the rate of adjustment in the hospital single conversion index in 2020 was 2.0%, and the outpatient and hospitalization conversion rates for hospitals were 2.2% and 2.3%, respectively. In addition, a combination of outpatient and inpatient conversion factors can be used for the adjustment. Second, as a measure to establish a medical delivery system, instead of adjusting the addition rate, a method of interlocking the addition rate and the conversion factor is proposed. Third, it is necessary to develop a model that enables target management of volumes, in addition to the outpatient conversion factor, the inpatient conversion factor, and the adjustment coefficient.

• Journal of Wetlands Research
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• v.21 no.1
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• pp.84-94
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• 2019

The Seocheon and Yubu Island mudflats in Geum Estuary are important stopover sites for migratory birds as energy supplementation area in the East Asia-Australasian Flyway. Benthic invertebrates in the tidal flats are important food resources for the migratory birds. In other words, benthic invertebrates in the tidal flats play an important ecological role in energy flow. This study was conducted to investigate the relationship between benthic invertebrate assemblages and environmental factors in Seocheon and Yubudo tidal flats in the Geum Estuary. As a result of the benthic invertebrate assemblage during the fall migration season, the total species number was 147, density and biomass were $1,772{\pm}1,342individuals/m^2$ and $445.1{\pm}807.6g/m^2$, respectively. Based on the appearance species and the density data, the result of analysis of mutual similarity among sampling sites was divided into two groups. Group A was the Macrophthalmus-Heteromastus community and Group B was the Spio-Urothoe-Mandibulophoxus community. Group B showed higher mean species number, density and biomass than Group A. The BIO-ENV analysis showed that the benthic invertebrate assemblages were most affected by the combination of sand content % and sediment sorting (${\rho}=0.500$). The variables of significant relationship with species number and biomass were sediment sorting (p=0.015) and the pore water DO(Dissolved Oxygen, p=0.003) in sediment, respectively.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.3
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• pp.537-542
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• 2022

There is a limit to the current indoor air quality (IAQ) monitoring method using fixed sensors and devices. A mobile robot for IAQ monitoring was developed by mounting IAQ monitoring sensors on a small multi-legged robot to minimize vibration and protect the sensors from vibration while robot moves. The developed mobile robot used a simple gait mechanism to enable the robot to move forward, backward, and turns only with the combination of forward and reverse rotation of the two DC motors. Due to the simple gait mechanism, not only IAQ data measurements but also gait motion control were processed using a single Arduino board. Because the mobile robot has small number of electronic components and low power consumption, a relatively low-capacity battery was mounted on the robot to reduce the weight of the battery. The weight of mobile robot is 1.4kg including links, various IAQ sensors, motors, and battery. The gait and turning speed of the mobile robot was measured at 3.75 cm/sec and 14.13 rad/sec. The maximum height where the robot leg could reach was 33 mm, but the mobile robot was able to overcome the bumps up to 24 mm.

• Journal of The Korean Association of Information Education
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• v.26 no.4
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• pp.229-238
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• 2022

At the time of discussing the 2022 revised curriculum, the demand for normalization of information education is increasing. This study was conducted on the case of the information curriculum for the upper elementary grades responding to such needs. For 14 6th grade students of Elementary School B in K Metropolitan City, 4 core areas of the information curriculum, including computing system, data, algorithm & programming, and digital culture, were covered through classes. Cooperative classes were conducted between students by using the cloud-based application according to the class. In addition, it was intended to supplement the curriculum by suggesting ideas for artificial intelligence education area, and to improve the density of research with additional investigation on foreign information education cases. However, the need for independent organization of the information curriculum was strongly confirmed in that the current curriculum for information classes lacked sufficient school hours and had to be operated in combination with other subjects in the form of a project for this case study. It is hoped that this study will serve as a small foundation for the establishment of the information curriculum for the upper elementary grades in the future.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.3
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• pp.9-14
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• 2024

Hue, value, and chroma are the fundamental colour components used in colour property research to identify colour in the digital media environment. In the Munsell colour system, which is based on the characteristics of visual perception, the basic properties are classified into hue, value, and chroma. The methods for recording these three properties can be divided into the colour appearance system and the colour mixing system: in the former, they are documented based on a colour chart that focuses on visual perception, and in the latter, accurate numerical records are kept without concern for discolouration. Colour terminology is crucial for conveying and expressing colours, and colours can be classified and defined according to the combination of hue, value, and chroma. With the development of various media, it has become possible to represent a range of colours previously unachievable, necessitating basic research into the characteristics of colour perception by further subdividing digital-oriented colour studies. In this study, we conducted psychophysical experiments to identify and analyse the categories of value and chroma needed to recognise each colour among the ten representative colours of the Munsell colour system, based on visual perception on a display. This study analyses the results of these experiments, defines their significance as foundational research data on colour perception characteristics, and suggests directions for future research.

• Tuberculosis and Respiratory Diseases
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• v.71 no.6
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• pp.400-407
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• 2011

Background: There were a few studies which were conducted to know about the behavior of the chronic obstructive pulmonary diseases (COPD) patients. The aims of this study was to explore the behaviour of COPD patients, such as awareness and impact of disease, the pathway of visiting doctors, and the treatment pattern and preference. Methods: A face-to-face interview of 300 subjects with COPD was conducted. Results: The most concerned symptom which made the respondents to visit the hospital was 'breathlessness' (78%). Only 58% of them knew the exact diagnosis. Seventy-three percent of them visited the hospital 'once a month' or 'once every 2 month'. They have made 12.8 prescheduled visits to the hospital in the past 1 year. Unscheduled visits and hospital stay figured to two in the past year. Only 11% of respondents felt they were currently in good health. 'Severe' and 'very severe' COPD patients perceived their health to be in a worse condition than 'mild' and 'moderate' COPD patients. When conditions worsened, 42% of patients were hospitalized. The most common prescription treatment was a fixed combination of inhaled corticosteroids and long-acting ${\beta}2$ agonists (48%), followed by a long acting anticholinergics (38%). Conclusion: Over forty percent of the patients didn't know exactly about their condition. Most of them had a negative attitude toward their current health status. Doctors need to know more about COPD patients in terms of their attitude toward the disease, impact of the disease, interaction with healthcare professionals and treatment related problems.