• Journal of The Korean Association For Science Education
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• v.26 no.6
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• pp.753-764
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• 2006

The concept of blood circulation is so complex, dynamic and abstract that students have difficulty in understanding it and students' preconceptions hardly change into scientific concepts even after the lessons. The purpose of this study is to examine middle school, high school, and undergraduate students' understanding of blood circulation and to find the reason why the lack of deep understanding is displayed in students' explanations for the blood circulation. The study consists of three parts. First, the test was designed to investigate students' ideas for blood circulation as components of the structure, the function, the behavior and the mechanism. Second, the test was applied to 7th, 10th and 13th graders to investigate the students' understanding of blood circulation and categorize the types of students' blood circulation model according to their academic level. Finally, the concepts the students had little understanding of were analyzed to decide which ontological category they fell into and further to inquire the characteristics of each concept. The results showed that many students comprehend the structure and the function of blood circulation components well, and there was no significant difference in students' understanding according to the academic level. In contrast, understanding the behavior and the mechanism of circulatory components has remarkably improved in high school students and undergraduates majoring in science and engineering. Also, students' blood circulation models were classified into seven different types. High school students and undergraduates majoring in science and engineering demonstrated a significantly higher percentage on the type of double-loop-branch compared to other academic levels. In addition, it was found that the lack of deep understanding was caused by students' misconceiving the 'equilibrium' category as 'event' category.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.219-224
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• 2007

Two monitoring buoys equipped with ADCP were deployed at the deepest positions along the trough of the central Gwangyang Bay in spring 2006 in order to study the circulation in the bay. Northward velocity is commonly dominant at both stations located in the eastern part of the channel, which supports the cyclonic circulation accompanied by the southward flow in the western part. The southern station has a distinct two-layer structure with current reversal at 14 m depth and increasing northward velocity in the lower layer to 36 m depth close to the bottom. At the northern station the northward flow becomes accelerated due to the decrease in the cross-sectional area and this northward current is dominant even in the upper layer. In the modal structure from the EOF analysis, the first mode has 74% of total variance at the northern station whereas it is 67% but the baroclinic portion increases at the southern station. The typical northward velocity is about 10 cm/s which is associated with the cyclonic circulation. Subtidal variability due to the local wind effect is negligible, but the nonlocal response associated with offshore Ekman flux by the zonal wind is found during strong wind events.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.809-815
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• 2023

This study was conducted to find out the correlation between meat quality and muscle fat ratio in pork part meat (pork belly and shoulder butt) using CT (computed tomography) imaging technique. After 24 hours from slaughter, pork loin and belly were individually prepared from the left semiconductors of 26 pigs for CT measurement. The image obtained from CT scans was checked through the picture archiving and communications system (PACS). The volume of muscle and fat in the pork belly and shoulder butt of cross-sectional images taken by CT was estimated using Vitrea workstation version 7. This assemblage was further processed through Vitrea post-processing software to automatically calculate the volumes (Fig. 1). The volumes were measured in milliliters (mL). In addition to volume calculation, a three-dimensional reconstruction of the organ under consideration was generated. Pearson's correlation coefficient was analyzed to evaluate the relationship by region (pork belly, pork shoulder butt), and statistical processing was performed using GraphPad Prism 8. The muscle-fat ratios of pork belly taken by CT was 1 : 0.86, while that of pork shoulder butt was 1 : 0.37. As a result of CT analysis of the correlation coefficient between pork belly and shoulder butt compared to the muscle-fat ratio, the correlation coefficient was 0.5679 (R² = 0.3295, p < 0.01). CT imaging provided very good estimates of muscle contents in cuts and in the whole carcass.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.50.1-50.11
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• 2023

Background: The rise in telecommuting or non-face-to-face work owing to the coronavirus disease 2019 pandemic has fueled conversations regarding the "right to disconnect." Although evidence suggests that receiving work-related communications through telecommunication devices outside of work hours may lead to various symptoms and illnesses, limited research has been undertaken on these symptoms. This study therefore aims to investigate the correlation between receiving work communications through telecommunication devices after work hours and the occurrence of work-related headaches and eyestrain in full-time, non-shift white-collar workers. Methods: This study used data from the 6th Korean Working Conditions Survey. The frequency of using telecommunication devices for work purposes outside of working hours was divided into five categories: "Every day," "Several times a week," "Several times a month," "Rarely," and "Never." Work-related headaches and eyestrain were categorized based on a "yes" or "no" response to the survey questions. Descriptive statistics, χ² tests, and multiple logistic regression analyses were performed using SPSS 27.0. Results: After adjusting for sex, age, income level, education, occupation, workplace size, work hours, and sleep disorders, the odds ratio (OR) of work-related headaches and eyestrain based on frequency of telecommunication device usage were as follows: "rarely" (OR: 1.292; 95% confidence interval [CI]: 1.111-1.503), "several times a month" (OR: 1.551; 95% CI: 1.249-1.926), "several times a week" (OR: 1.474; 95% CI: 1.217-1.784), and "every day" (OR: 1.548; 95% CI: 1.321-1.813). Conclusions: Employees who use telecommunication devices for work after regular hours are more susceptible to experiencing work-related headaches and eyestrain compared to those who do not. However, there is a dearth of research examining the physical and mental health impacts of using telecommunication devices for after-hours work. Furthermore, the existing preventative measures in Korea are insufficient. Consequently, it is imperative to develop effective measures and conduct additional research to address this issue.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.4.1-4.11
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• 2023

Background: Shift work has been shown to increase the risk of cardiovascular disease (CVD) based on several evidences. The classic risk factors of CVD include age, hypertension, smoking, obesity and diabetes. Recently, the serum homocysteine level has been reported to be a valuable indicator of CVD risk. This study aimed to determine the variation in serum homocysteine level as a cardiovascular risk indicator among female workers according to shift work. Methods: The data of regular health examination of workers at an electronic manufacturing services company in Yeongnam region, South Korea in 2019 were examined in this study. The investigation was based on a cross-sectional study conducted on 697 female workers (199 day workers and 498 shift workers). The sociodemographic and biochemical characteristics were compared between day workers and shift workers. Through a logistic regression analysis, the odds ratio (OR) of the increased serum homocysteine level in relation to shift work was determined. Results: Compared to female day workers, female shift workers showed significantly higher level of serum homocysteine (8.85 ± 2.16 vs. 9.42 ± 2.04 μmol/mL; p = 0.001). The OR of day workers against shift workers was 1.81 (95% confidence interval [CI]: 1.25-2.63). With the adjustment of variables that may influence the level of serum homocysteine, the adjusted OR was 1.68 (95% CI: 1.09-2.60). Conclusions: The serum homocysteine level was significantly higher in shift workers than in day workers. It is thus likely to be a useful predictor of CVD in shift workers.

• Clinical Nutrition Research
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• v.12 no.4
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• pp.283-292
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• 2023

The aim of this study was to investigate whether dairy intake was associated with the severity of coronavirus disease 2019 (COVID-19) disease and the probability of hospitalization of patients. This cross-sectional study was conducted on 141 patients with COVID-19 with an average age of 46.23 ± 15.88 years. The number of men (52.5%) participating in this study was higher than that of women. The association between dairy intake and COVID-19 was evaluated by multivariable logistic regression analysis. The risk of hospitalization in the highest tertile of dairy intake was 31% lower than in the lowest tertile (odds ratio [OR], 0.69; 95% confidence interval [CI], 0.37-1.25, p trend = 0.023). Higher milk and yogurt intake was associated with a reduced risk of hospitalization due to COVID-19. Patients in the third tertiles were about 65% (p for trend = 0.014) and 12% (p for trend = 0.050) less likely to be hospitalized than those in the first tertile, respectively. Dairy consumption, especially low-fat ones, was associated with a lower risk of hospitalization due to COVID-19 and lower severity of COVID-19.

• The Journal of Korean Society for School & Community Health Education
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• v.25 no.2
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• pp.71-81
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• 2024

Purpose: This study aims to identify research trends in papers related to the elderly and the disabled published in the journal of Korean society for school & community health education from 2000 to 2023 and seek the direction of the academic development of this journal in the future. Method: A total of 26 articles related to the elderly and the disabled, who are vulnerable groups, were analyzed by year by analyzing the specific subjects, research themes, research design, data collection methods, and keywords of papers published from 2000 to 2023. Results: Looking at the research subjects, studies on the elderly (18 studies) accounted for a larger proportion than studies on the disabled (8 studies). Research themes in the field of healthy living practices for the elderly (44.4%) and research in the field of mental health management (37.5%) for the disabled accounted for a high proportion. The design of research were mostly quantitative and cross-sectional studies. Data collection is mostly based on secondary data. In studies targeting the elderly, keywords appeared in the following order: 'Health' and 'Elderly'. And research targeting the disabled appeared in the following order: 'Disabilities', 'Health', and 'COVID-19'. Additionally, research on the elderly and the disabled has recently shown an increasing trend. Conclusion: Research on the elderly and the disabled has been conducted in line with the purpose of the Korean society for school & community health education, However, In terms of quantitative expansion and qualitative research, research themes, research designs, and data collection methods must be diversified. Methods, public perception. Additionally, research on vulnerable groups that fit the public health promotion and health education paradigm is needed.

• Nutrition Research and Practice
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• v.18 no.4
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• pp.511-522
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• 2024

BACKGROUND/OBJECTIVES: The study examined the association between homocysteine and diabetes mellitus in patients with H-type hypertension and assessed the possible effect modifiers. SUBJECTS/METHODS: This cross-sectional study included 1,255 eligible participants in the 'H-type Hypertension Management and Stroke Prevention Strategic International Science and Technology Innovation Cooperation Project' among rural Chinese people with H-type hypertension. A multivariate logistic regression model was used to evaluate the relationship between homocysteine and diabetes mellitus. RESULTS: The mean level of total homocysteine (tHcy) in the diabetes mellitus population was 19.37 μmol/L, which was significantly higher than the non-diabetic patients (18.18 μmol/L). When tHcy was analyzed as a continuous variable, the odds ratio (OR) of diabetes was 1.17 (95% confidence interval [CI], 1.01-1.35; per interquartile range). When tHcy was stratified according to the quintile, the ORs for diabetes were 2.86 (95% CI, 1.22-6.69) in the highest quintile (tHcy ≥ 20.60 μmol/L) compared to the reference group (tHcy < 12.04 μmol/L). When tHcy was grouped by 15 μmol/L and 20 μmol/L, patients with tHcy ≥ 20 μmol/L had a significantly (P = 0.037) higher risk of diabetes (OR, 2.03; 95% CI, 1.04-3.96) than in those with tHcy < 15 μmol/L. Subgroup analysis showed that the tHcy-diabetes association was unaffected by other variables. CONCLUSION: In this study of rural Chinese people with H-type hypertension, the tHcy levels showed a positive association with diabetes mellitus. This independent association is unaffected by other potential risk factors.

• Journal of the Korea Institute of Building Construction
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• v.24 no.4
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• pp.447-458
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• 2024

This study investigates the effectiveness of Building Information Modeling(BIM) software, specifically SketchUp and Revit, in reducing errors during quantity take-off(QTO) for complex building elements. While 3D modeling offers advantages, existing software may not fully account for manufacturing discrepancies, such as variations in concrete cover thickness and reinforcing bar radius. To address this limitation, this research proposes a BIM-based QTO method for high-insulation wall panels with intricate details. The method utilizes a BIM family library, focusing on key parameters like concrete cover thickness and inner radius of shear reinforcement. A case study compared the cross-sectional details of a wall panel modeled in Revit with the actual manufactured specimen. The analysis revealed a 12% reduction in modeled concrete cover thickness and a 1.27 times larger modeled inner radius of the shear bar compared to the real-world values. The proposed method incorporates these manufacturing variations into the Revit model of the high-insulation wall panel. Software like Navisworks facilitates the identification and correction of any material interferences arising from these adjustments. Furthermore, the method employs a unit wall concept(1m²) to account for the volume of various materials, including insulation and splice sleeves at joints. This allows for the identification of a similar existing family within the BIM library(e.g., "Double RC wall with embedded insulation") that reflects the actual material quantities used in the wall panel. By incorporating these manufacturing-induced variations, the proposed method offers a more accurate QTO process for complex high-insulation wall panels. The "Double RC wall with embedded insulation" family within the Revit program serves as a valuable tool for material quantity estimation in such scenarios.

• Therapeutic Science for Rehabilitation
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• v.13 no.3
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• pp.69-83
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• 2024

Objective : This study investigated the prevalence of dysphagia in older adults in Gangwon Special Self-Governing Province and its impact on Quality of Life (QoL) and educational needs. Methods : A cross-sectional survey was conducted from August 1 to 15, 2023, with 207 cognitively normal older adults from three senior welfare centers. Data included general characteristics, Korean-version of the Eating Assessment Tool (K-EAT-10), Swallowing-QoL, and educational needs related to swallowing disorders. Dysphagia was defined by a K-EAT-10 score of 3 or higher. Participants were divided into normal and risk groups for analysis using chi-square and Independent t-test. Results : The prevalence of dysphagia risk (K-EAT-10 score of 3 or higher) was 41.5% (86 individuals). Among the 92 individuals reporting dysphagia symptoms, 64 (69.6%) were at risk. QoL was significantly lower in the risk group, especially among those living alone or with denture discomfort. The most preferred educational need was training in eating solid foods (Mean = 4.27), with higher needs in the dysphagia risk group. Conclusion : This study underscores the prevalence of dysphagia, its impact on QoL, and the need for educational programs. Emphasizing prevention, public awareness, and early detection, along with the role of dysphagia rehabilitation experts and community collaboration, is essential for supporting healthy aging.