• Korean Journal of Radiology
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• v.22 no.4
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• pp.624-633
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• 2021

Objective: To evaluate the reliability of CT measurements of muscle quantity and quality using variable CT parameters. Materials and Methods: A phantom, simulating the L2-4 vertebral levels, was used for this study. CT images were repeatedly acquired with modulation of tube voltage, tube current, slice thickness, and the image reconstruction algorithm. Reference standard muscle compartments were obtained from the reference maps of the phantom. Cross-sectional area based on the Hounsfield unit (HU) thresholds of muscle and its components, and the mean density of the reference standard muscle compartment, were used to measure the muscle quantity and quality using different CT protocols. Signal-to-noise ratios (SNRs) were calculated in the images acquired with different settings. Results: The skeletal muscle area (threshold, -29 to 150 HU) was constant, regardless of the protocol, occupying at least 91.7% of the reference standard muscle compartment. Conversely, normal attenuation muscle area (30-150 HU) was not constant in the different protocols, varying between 59.7% and 81.7% of the reference standard muscle compartment. The mean density was lower than the target density stated by the manufacturer (45 HU) in all cases (range, 39.0-44.9 HU). The SNR decreased with low tube voltage, low tube current, and in sections with thin slices, whereas it increased when the iterative reconstruction algorithm was used. Conclusion: Measurement of muscle quantity using HU threshold was reliable, regardless of the CT protocol used. Conversely, the measurement of muscle quality using the mean density and narrow HU thresholds were inconsistent and inaccurate across different CT protocols. Therefore, further studies are warranted in future to determine the optimal CT protocols for reliable measurements of muscle quality.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.27 no.3
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• pp.158-167
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• 2024

Purpose: To evaluate the prevalence of vertebral fracture (VF) in children with chronic liver disease (CLD) with and without liver transplantation (LT) and to determine the associated factors. Methods: A cross-sectional study was conducted. Patients aged 3-21 years with CLD both before and after LT were enrolled in the study. Lateral thoracolumbar spine radiographs were obtained and assessed for VF using Mäkitie's method. Clinical and biochemical data were collected. Results: We enrolled 147 patients (80 females; median age 8.8 years [interquartile range 6.0-11.8]; 110 [74.8%] in the LT group and 37 [25.2%] in the non-LT group). VF was identified in 21 patients (14.3%): 17/110 (15.5%) in the LT group and 4/37 (10.8%) in the non-LT group (p=0.54). Back pain was noted in only three patients with VF. In the univariate analysis, a height z-score below -2.0 (p=0.010), pre-LT hepatopulmonary syndrome (p=0.014), elevated serum direct and total bilirubin levels (p=0.037 and p=0.049, respectively), and vitamin D deficiency at 1-year post-LT (p=0.048) were associated with VF in the LT group. In multivariate analysis, height z-score below -2.0 was the only significant associated factor (odds ratio, 5.94; 95% confidence interval, 1.49-23.76; p=0.012) for VF. All VFs in the non-LT group were reported in males. Conclusion: In children with CLD, VF is common before and after LT. Most patients with VF are asymptomatic. Screening for VF should be considered in patients with a height z-score below -2.0 after LT.

• 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 Hepato-Biliary-Pancreatic Surgery
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• v.27 no.4
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• pp.380-387
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• 2023

Backgrounds/Aims: In 2019, the grading and staging system for neuroendocrine neoplasms (NENs) was significantly changed. In this study, we report the clinicopathological characteristics and surgical outcomes of patients with extrahepatic biliary NENs who underwent curative resection with or without adjuvant treatment. Methods: We retrospectively reviewed a database of 16 patients who developed NENs, neuroendocrine carcinoma (NEC), and mixed endocrine non-endocrine neoplasms (MiNENs) after curative resection. Among them, eight patients had ampulla of Vater (AoV) tumors, and eight patients had non-AoV tumors. Results: G1 and G2 were more frequently observed in the AoV group than in the non-AoV group (12.5% and 62.5%, respectively). In contrast, NEC and MiNEN were more common in the non-AoV group (50.0%). High Ki-67 index (> 20%) and perineural invasion (PNI) were more frequently observed in the non-AoV group. Advanced age (> 65 years), mitotic count > 20 per 2 mm², and Ki-67 index > 20% were strongly correlated with patient survival (p = 0.018, 0.009, and 0.044, respectively). Advanced age (> 65 years) and mitotic count > 20 per 2 mm² were significantly correlated with disease recurrence (p = 0.033 and 0.010, respectively). Conclusions: AoV and non-AoV tumors had significant differences in the histologic grade, Ki67, and PNI. Patients with non-AoV tumors had an increased risk for survival and recurrence than those in the AoV group. For extrahepatic biliary NENs, early detection of tumors, adequate surgery, and aggressive adjuvant treatment for high-risk patients are important to achieve long-term survival and prevent disease recurrence.

• Journal of Preventive Medicine and Public Health
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• v.57 no.1
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• pp.37-46
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• 2024

Objectives: The objective of this study was to characterize mental health issues among Vietnamese healthcare workers (HCWs) and to identify related factors. Methods: A cross-sectional study was conducted with 990 HCWs in 2021. Their mental health status was measured using the Depression, Anxiety, and Stress Scale. Results: In total, 49.9%, 52.3%, and 29.8% of respondents were found to have depression, anxiety, and stress, respectively. The multivariable linear regression model revealed that factors associated with increased anxiety scores included depression scores (β, 0.45; 95% confidence interval [CI], 0.39 to 0.51) and stress scores (β, 0.46; 95% CI, 0.41 to 0.52). Factors associated with increased depression scores included being frontline HCWs (β, 0.57; 95% CI, 0.10 to 1.10), stress scores (β, 0.50; 95% CI, 0.45 to 0.56), and anxiety scores (β, 0.41; 95% CI, 0.36 to 0.47), while working experience was associated with reduced depression scores (β, -0.08; 95% CI, -0.16 to -0.01). Factors associated with increased stress scores included working experience (β, 0.08; 95% CI, 0.00 to 0.16), personal protective equipment interference with daily activities (β, 0.55; 95% CI, 0.07 to 1.00), depression scores (β, 0.54; 95% CI, 0.48 to 0.59), and anxiety scores (β, 0.45; 95% CI, 0.39 to 0.50), while age was associated with reduced stress scores (β, -0.12; 95% CI, -0.20 to -0.05). Conclusions: Specific interventions are necessary to enhance and promote the mental health of HCWs so they can successfully cope with the circumstances of the pandemic.

• Journal of Korean Physical Therapy Science
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• v.31 no.1
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• pp.16-32
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• 2024

Background: Exercise equipments and assistive devices for the disabled are being developed, but improvements for usability are still needed. The purpose of this study was to improve and utilize the developed exercise equipment and assistance devices by conducting usability test for people with spinal cord injury. Design: Cross-sectional Study. Methods: Scenarios and usability indicators were derived by conducting a preliminary usability test, 5 non-disabled men and women aged 19 or older. In the scenario, a total of 9 tasks were sequentially performed, including 2 tasks of entry and exit, 5 tasks of assistance devices and weight stack adjustment, and 2 tasks of pre exercise and exercise. The usability indicators were task success (success or fail), execution time (sec), safety, and convenience. For safety, 7 questions (Likert scale, 1~5 point) related to safety, stability and hazard were derived, and for convenience, the system usability scale (SUS score) was used (range: 0~100, 50 percentile rank is 68 point). Results: As a result of the usability test of people with spinal cord injury, there was a large variation among subjects in the task of adjusting the position of the pulley and support in the execution time (11.64~25.44 seconds), and one person failed to adjust the pulley. The safety level showed a lower score (score = 3 points) than other items in the item of entrapment or skin pressure, and in the case of SUS, the average score was 64.5 points, which was close to the acceptable level. Conclusion: Through the usability test, it was confirmed that exercise equipment for the disabled needs improvement in operability, pinching, and pressure, and that it is necessary to develop an assistive device that provides unrestrained posture information (biofeedback) to maintain correct posture during exercise.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4357-4366
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• 2023

MARS-KS, a domestic regulatory confirmatory code of Republic of Korea, had been developed by integrating RELAP5/MOD2 and COBRA-TF. The integration of COBRA-TF allowed to extend the capability of MARS-KS, limited to one-dimensional analysis, to multi-dimensional analysis. The use of COBRA-TF was mainly focused on subchannel analyses for simulating multi-dimensional behavior within the reactor core. However, this feature has been remained as a legacy without ongoing maintenance. Meanwhile, MARS-KS also includes its own multidimensional component, namely MULTID, which is also feasible to simulate three-dimensional convection and diffusion. The MULTID is capable of modeling the turbulent diffusion using simple mixing length model. The implementation of the turbulent mixing is of importance for analyzing the reactor core where a disturbing cross-sectional structure of rod bundle makes the flow perturbation and corresponding mixing stronger. In addition, the presence of this turbulent behavior allows the secondary transports with net mass exchange between subchannels. However, a series of assessments performed in previous studies revealed that the turbulence model of the MULTID could not simulate the aforementioned effective mixing occurred in the subchannel-scale problems. This is obvious consequence since the physical models of the MULTID neglect the effect of mass transport and thereby, it cannot model the void drift effect and resulting phasic distribution within a bundle. Thus, in this study, the turbulence mixing model of the MULTID has been improved by means of the inter-channel mixing model, widely utilized in subchannel analysis, in order to extend the application of the MULTID to small-scale problems. A series of assessments has been performed against rod bundle experiments, namely GE 3X3 and PSBT, to evaluate the performance of the introduced mixing model. The assessment results revealed that the application of the inter-channel mixing model allowed to enhance the prediction of the MULTID in subchannel scale problems. In addition, it was indicated that the code could not predict appropriate phasic distribution in the rod bundle without the model. Considering that the proper prediction of the phasic distribution is important when considering pin-based and/or assembly-based expressions of the reactor core, the results of this study clearly indicate that the inter-channel mixing model is required for analyzing the rod bundle, appropriately.

• Journal of the Korean Society of Radiology
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• v.84 no.3
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• pp.606-614
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• 2023

Purpose This study aimed to evaluate the efficacy and safety of transcatheter arterial embolization (TAE) for bleeding due to uterine body cancer. Materials and Methods In this retrospective study, six patients with varying types of uterine body cancer who underwent TAE for bleeding control were investigated. Angiographic findings, cross-sectional images, TAE details, and clinical outcomes were studied. Technical and clinical success rates were calculated. Results The identified patients had endometrioid adenocarcinoma, sarcoma, and gestational trophoblastic neoplasia, and most were patients with advanced-stage cancer. In four patients, tumor bleeding presented as vaginal bleeding. Technical success was achieved in all seven TAE procedures in six patients. Two patients with recurrent masses who had undergone hysterectomy presented with hematochezia, and TAE was able to provide technical success in these patients as well. The clinical success rate was 50%, indicating bleeding control for > 1 week. Rebleeding was directly associated with death in one patient. On the following day, mild fever was observed in one patient. Conclusion TAE can be considered an effective and safe method of bleeding control for uterine body cancer, especially during critical periods throughout the disease course of patients with inoperable, advanced-stage cancer.

• Korean Journal of Community Nutrition
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• v.29 no.3
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• pp.234-252
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• 2024

Objectives: This study examined the intake of energy and macronutrients among elementary, middle, and high school students according to household income before the COVID-19 pandemic (2016-2019), during the social distancing period (2020-2021), and after the social distancing measures were lifted (2022). Methods: We included 5,217 students aged 5-18 from the Korea National Health and Nutrition Examination Survey (KNHANES) conducted between 2016 and 2022. Dietary intake was assessed using one-day 24-hour dietary recalls. We estimated the least squares means (LS-means) of intake according to household income for each period using a weighted linear regression model, adjusted for age and sex. Differences in LS-means between the periods were analyzed using the t-test. Results: During the social distancing period, the LS-means of energy intake among students decreased significantly by 143.2 kcal/day compared to pre-pandemic levels (P < 0.001). Students from low-income households experienced a more pronounced decrease in energy intake (-379.1 kcal/day, P < 0.001) and macronutrient intake compared to those from other income groups. Energy intake at school significantly declined for all income groups during the social distancing period compared to before the pandemic. No significant changes in home energy intake were observed among low-income students, whereas there was an increase for students from higher-income groups. Before the pandemic, 8.5% of students from low-income households reported insufficient food due to economic difficulties; this figure rose to 21.3% during the pandemic. Conclusions: During the pandemic, students from low-income families experienced significantly lower intake of energy and macronutrients compared to pre-pandemic levels. The most substantial reductions were noted among low-income students, largely due to the lack of compensation for decreased school-based intake with increased intake at home.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.27 no.4
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• pp.258-265
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• 2024

Purpose: To date, there is no region-specific guideline for pediatric endoscopy training. This study aimed to illustrate the current status of pediatric endoscopy training in Asia-Pacific region and identify opportunities for improvement. Methods: A cross-sectional survey, using a standardized electronic questionnaire, was conducted among medical schools in the Asia-Pacific region in January 2024. Results: A total of 57 medical centers in 12 countries offering formal Pediatric Gastroenterology training programs participated in this regional survey. More than 75% of the centers had an average case load of <10 cases per week for both diagnostic and therapeutic endoscopies. Only 36% of the study programs employed competency-based outcomes for program development, whereas nearly half (48%) used volume-based curricula. Foreign body retrieval, polypectomy, percutaneous endoscopic gastrostomy, and esophageal variceal hemostasis, that is, sclerotherapy or band ligation (endoscopic variceal sclerotherapy and endoscopic variceal ligation), comprised the top four priorities that the trainees should acquire in the autonomous stage (unconscious) of competence. Regarding the learning environment, only 31.5% provided formal hands-on workshops/simulation training. The direct observation of procedural skills was the most commonly used assessment method. The application of a quality assurance (QA) system in both educational and patient care (Pediatric Endoscopy Quality Improvement Network) aspects was present in only 28% and 17% of the centers, respectively. Conclusion: Compared with Western academic societies, the limited availability of cases remains a major concern. To close this gap, simulation and adult endoscopy training are essential. The implementation of reliable and valid assessment tools and QA systems can lead to significant development in future programs.