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In this study, the WRF-Chem v4.4 model was utilized to evaluate three bottom-up emission inventories (EDGAR-HTAP v2, v3, and KORUS v5) using surface and aircraft data in East Asia during the Korea-United States Air Quality (KORUS-AQ) campaign period in 2016. All emission inventories were found to reproduce the diurnal variations of O3 and NO2 as compared to the surface monitor data. However, the spatial distributions of the daily maximum 8-hour average (MDA8) O3 in the model do not completely align with the observations. The model MDA8 O3 had a negative (positive) bias north (south) of 30°N over China. All simulations underestimated the observed CO by 50-60% over China and South Korea. In the Seoul Metropolitan Area (SMA), EDGAR-HTAP v2, v3, and KORUS v5 simulated the vertical shapes and diurnal patterns of O3 and other precursors effectively, but the model underestimated the observed O3, CO and HCHO concentrations. Notably, the model aromatic VOCs were significantly underestimated with the three bottom-up emission inventories, although the KORUS v5 shows improvements. The model isoprene estimations had a positive bias relative to the observations, suggesting that the Model of Emissions of Gases and Aerosols from Nature (MEGAN) version 2.04 overestimated isoprene emissions. Additional model simulations were conducted by doubling CO and VOC emissions over China and South Korea to investigate the causes of the model O3 biases and the effects of the long-range transport on the O3 over South Korea. The doubled CO and VOC emission simulations improved the model O3 simulations for the local emission dominant case, but led to the model O3 overestimations for the transport dominant case, which emphasizes the need for accurate representations of the local VOC emissions over South Korea. [ABSTRACT FROM AUTHOR]

Background: Coronavirus disease 2019 (COVID-19) can cause various extrapulmonary sequelae, including diabetes. However, it is unclear whether these effects persist 30 days after diagnosis. Hence, we investigated the incidence of newly diagnosed type 2 diabetes mellitus (T2DM) in the post-acute phase of COVID-19. Methods: This cohort study used data from the Health Insurance Review and Assessment Service, a representative national healthcare database in Korea. We established a cohort of 348,180 individuals diagnosed with COVID-19 without a history of diabetes between January 2020 and September 2021. The control group consisted of sex- and age-matched individuals with neither a history of diabetes nor COVID-19. We assessed the hazard ratios (HR) of newly diagnosed T2DM patients with COVID-19 compared to controls, adjusted for age, sex, and the presence of hypertension and dyslipidemia. Results: In the post-acute phase, patients with COVID-19 had an increased risk of newly diagnosed T2DM compared to those without COVID-19 (adjusted HR, 1.30; 95% confidence interval [CI], 1.27 to 1.33). The adjusted HRs of non-hospitalized, hospitalized, and intensive care unit-admitted patients were 1.14 (95% CI, 1.08 to 1.19), 1.34 (95% CI, 1.30 to 1.38), and 1.78 (95% CI, 1.59 to 1.99), respectively. The risk of T2DM in patients who were not administered glucocorticoids also increased (adjusted HR, 1.29; 95% CI, 1.25 to 1.32). Conclusion: COVID-19 may increase the risk of developing T2DM beyond the acute period. The higher the severity of COVID-19 in the acute phase, the higher the risk of newly diagnosed T2DM. Therefore, T2DM should be included as a component of managing long-term COVID-19. [ABSTRACT FROM AUTHOR]

Background and Objectives: Diet and smartphone use are daily routines that can affect adolescents' mental health. This study investigated whether the frequency of the consumption of certain foods is associated with the duration of smartphone use and problems caused by smartphone overuse in adolescents.Methods and Study Design: Food consumption and smartphone use were investigated in 62,276 Korean adolescents aged 12-18 years by using a nationwide self-report survey. Food intake was assessed on a seven-point scale ("never" to "1, 2, and 3 or more times per day") for nine items: fruits, vegetables, milk, soda, energy drinks, sweetened beverages, fast food, instant noodles, and snacks. The durations of smartphone use and problematic use were determined using self-report items.Results: Most respondents (66.5%) used smartphones over 2 hours per day. Higher consumption levels of fruits (F=151.8; p<0.001), vegetables (F=119.9; p<0.001), and milk (F=33.0; p<0.001) were associated with significantly lower smartphone usage, whereas higher consumption levels of soda (F=292.5; p<0.001), energy drinks (F=24.0; p<0.001), sweetened beverages (F=224.8; p<0.001), fast food (F=192.1; p<0.001), instant noodles (F=196.2; p<0.001), and snacks (F=131.6; p<0.001) were positively associated with higher smartphone usage.Conclusions: Our findings provide useful clinical information regarding the association between dietary habits and smartphone use in adolescents. Future studies should investigate underlying mechanisms and examine the efficacy of dietary interventions for adolescents with excessive smartphone use. [ABSTRACT FROM AUTHOR]

Background: This phase 3 study evaluated the efficacy and safety of 6-month treatment with romosozumab in Korean postmenopausal women with osteoporosis. Methods: Sixty-seven postmenopausal women with osteoporosis (bone mineral density [BMD] T-scores =-2.5 at the lumbar spine, total hip, or femoral neck) were randomized (1:1) to receive monthly subcutaneous injections of romosozumab (210 mg; n=34) or placebo (n=33) for 6 months. Results: At month 6, the difference in the least square (LS) mean percent change from baseline in lumbar spine BMD (primary efficacy endpoint) between the romosozumab (9.5%) and placebo (-0.1%) groups was significant (9.6%; 95% confidence interval, 7.6 to 11.5; P<0.001). The difference in the LS mean percent change from baseline was also significant for total hip and femoral neck BMD (secondary efficacy endpoints). After treatment with romosozumab, the percent change from baseline in procollagen type 1 Nterminal propeptide transiently increased at months 1 and 3, while that in C-terminal telopeptide of type 1 collagen showed a sustained decrease. No events of cancer, hypocalcemia, injection site reaction, positively adjudicated atypical femoral fracture or osteonecrosis of the jaw, or positively adjudicated serious cardiovascular adverse events were observed. At month 9, 17.6% and 2.9% of patients in the romosozumab group developed binding and neutralizing antibodies, respectively. Conclusion: Treatment with romosozumab for 6 months was well tolerated and significantly increased lumbar spine, total hip, and femoral neck BMD compared with placebo in Korean postmenopausal women with osteoporosis (ClinicalTrials.gov identifier NCT02791516). [ABSTRACT FROM AUTHOR]

Objectives: As a protective measure to slow down the transmission of coronavirus disease 2019 in Korea, social distancing was implemented from February 29th, 2020. This study aimed to evaluate the prevalence of domestic incidents and intentional injury during March 2020 when social distancing was in effect. Methods: There were 12,638 patients who visited the Level 1 trauma center of Chungnam province with injuries from domestic incidents, familial discord, and intentional injury. The prevalence of injuries during March 2020 was compared with the average of the previous 5 years, and the average for every March between 2015 and 2019. Results: The prevalence of domestic incidents in March 2020 was significantly higher than the 5-year average, and the average for every March from 2015 to 2019 (p < 0.001). Familial discord (p = 0.002) and intentional injury (p = 0.031) were more frequently observed in March 2020. Adolescents showed a markedly higher level of intentional injury in March 2020 than in both the 5-year average (p = 0.031), and average for every March over the previous 5 years (p = 0.037). Conclusion: The prevalence of domestic incidents and intentional injury were significantly higher during the period of social distancing in Korea. There is a need for social consensus, better policies, and psychological support services, especially if faced with a second or third wave of coronavirus disease. [ABSTRACT FROM AUTHOR]

Background: The prevalence of metabolic syndrome is increasing in Korea, particularly among young adults. This trend will increase the incidence of cardiovascular and metabolic diseases in the future. Therefore, it is imperative to detect and prevent metabolic abnormalities early in life. Here, we established a hospital-based biobank cohort to identify the most prevalent dysmetabolic phenotype. The aim of this report was to inform other researchers of our protocol and to share our data for future collaboration. Methods: The baseline examination comprised health-related questionnaires, anthropometric and handgrip strength measurements, bioelectrical impedance analysis of body composition, and nutritional assessment. Relevant biochemical parameters were measured, and oral glucose tolerance tests were performed. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria with Asian waist circumference criteria. Results: From a total of about 3,000 employees aged 20 to 59 years working at Seoul National University Bundang Hospital, 1,017 were enrolled from 2015 to 2016. The mean age was 34.5±8.4 years for men (n=311, 30.6%) and 30.9±8.5 years for women (n=706, 69.4%). The overall prevalence of metabolic syndrome was 7.6% (17.7% in men and 3.1% in women). Among the five components of metabolic syndrome, high blood pressure was the most prevalent in both men (51.4%) and women (13.8%). Conclusion: Although further follow-up data are needed, we expect that more adverse cardiovascular events may occur in men than in women. This hospital-based cohort will serve as the foundation for a comprehensive evaluation of metabolic syndrome and future cardiometabolic disease risk in middle-aged Koreans. [ABSTRACT FROM AUTHOR]

Background: Thyrotoxicosis is a common disease resulting from an excess of thyroid hormones, which affects many organ systems. The clinical symptoms and signs are relatively nonspecific and can vary depending on age, sex, comorbidities, and the duration and cause of the disease. Several symptom rating scales have been developed in an attempt to assess these symptoms objectively and have been applied to diagnosis or to evaluation of the response to treatment. The aim of this study was to assess the reliability and validity of the Korean version of the hyperthyroidism symptom scale (K-HSS). Methods: Twenty-eight thyrotoxic patients and 10 healthy subjects completed the K-HSS at baseline and after follow-up at Seoul National University Bundang Hospital. The correlation between K-HSS scores and thyroid function was analyzed. K-HSS scores were compared between baseline and follow-up in patient and control groups. Cronbach's a coefficient was calculated to demonstrate the internal consistency of K-HSS. Results: The mean age of the participants was 34.7±9.8 years and 13 (34.2%) were men. K-HSS scores demonstrated a significant positive correlation with serum free thyroxine concentration and decreased significantly with improved thyroid function. K-HSS scores were highest in subclinically thyrotoxic subjects, lower in patients who were euthyroid after treatment, and lowest in the control group at follow-up, but these differences were not significant. Cronbach's a coefficient for the K-HSS was 0.86. Conclusion: The K-HSS is a reliable and valid instrument for evaluating symptoms of thyrotoxicosis in Korean patients. [ABSTRACT FROM AUTHOR]