Objective: The coronavirus disease-2019 (COVID-19) pandemic has significantly altered daily life, potentially impacting children’s digital media usage. This study investigates changes in smart device usage among children in South Korea, considering the pandemic’s effects. Methods: A longitudinal analysis was conducted on a cohort of 313 children aged 8–11 years from 2018 to 2021. The study measured weekly usage of personal computers (PCs), tablet PCs, and smartphones, comparing pre-pandemic (up to 2020) and post-pandemic periods. Partial correlation analysis was employed to assess the impact of COVID-19, controlling for covariates such as age, household income, and parental education. Results: The analysis revealed a significant increase in smart device usage time following the onset of the pandemic. This increase remained statistically significant even after accounting for covariates. Notably, both age and maternal education level were significant factors influencing device usage. Conclusion This study demonstrates a significant shift in the digital behavior of children aged 8–11 in the context of the COVID-19 pandemic. The increase in smart device usage underscores the pandemic’s far-reaching impact on children’s daily routines and suggests a need for further research into its long-term effects. The findings highlight the importance of considering external societal changes when analyzing trends in digital media usage among children.

Objective: The coronavirus disease-2019 (COVID-19) pandemic has significantly altered daily life, potentially impacting children’s digital media usage. This study investigates changes in smart device usage among children in South Korea, considering the pandemic’s effects. Methods: A longitudinal analysis was conducted on a cohort of 313 children aged 8–11 years from 2018 to 2021. The study measured weekly usage of personal computers (PCs), tablet PCs, and smartphones, comparing pre-pandemic (up to 2020) and post-pandemic periods. Partial correlation analysis was employed to assess the impact of COVID-19, controlling for covariates such as age, household income, and parental education. Results: The analysis revealed a significant increase in smart device usage time following the onset of the pandemic. This increase remained statistically significant even after accounting for covariates. Notably, both age and maternal education level were significant factors influencing device usage. Conclusion This study demonstrates a significant shift in the digital behavior of children aged 8–11 in the context of the COVID-19 pandemic. The increase in smart device usage underscores the pandemic’s far-reaching impact on children’s daily routines and suggests a need for further research into its long-term effects. The findings highlight the importance of considering external societal changes when analyzing trends in digital media usage among children.

Objective: The coronavirus disease-2019 (COVID-19) pandemic has significantly altered daily life, potentially impacting children’s digital media usage. This study investigates changes in smart device usage among children in South Korea, considering the pandemic’s effects. Methods: A longitudinal analysis was conducted on a cohort of 313 children aged 8–11 years from 2018 to 2021. The study measured weekly usage of personal computers (PCs), tablet PCs, and smartphones, comparing pre-pandemic (up to 2020) and post-pandemic periods. Partial correlation analysis was employed to assess the impact of COVID-19, controlling for covariates such as age, household income, and parental education. Results: The analysis revealed a significant increase in smart device usage time following the onset of the pandemic. This increase remained statistically significant even after accounting for covariates. Notably, both age and maternal education level were significant factors influencing device usage. Conclusion This study demonstrates a significant shift in the digital behavior of children aged 8–11 in the context of the COVID-19 pandemic. The increase in smart device usage underscores the pandemic’s far-reaching impact on children’s daily routines and suggests a need for further research into its long-term effects. The findings highlight the importance of considering external societal changes when analyzing trends in digital media usage among children.

Objective: The coronavirus disease-2019 (COVID-19) pandemic has significantly altered daily life, potentially impacting children’s digital media usage. This study investigates changes in smart device usage among children in South Korea, considering the pandemic’s effects. Methods: A longitudinal analysis was conducted on a cohort of 313 children aged 8–11 years from 2018 to 2021. The study measured weekly usage of personal computers (PCs), tablet PCs, and smartphones, comparing pre-pandemic (up to 2020) and post-pandemic periods. Partial correlation analysis was employed to assess the impact of COVID-19, controlling for covariates such as age, household income, and parental education. Results: The analysis revealed a significant increase in smart device usage time following the onset of the pandemic. This increase remained statistically significant even after accounting for covariates. Notably, both age and maternal education level were significant factors influencing device usage. Conclusion This study demonstrates a significant shift in the digital behavior of children aged 8–11 in the context of the COVID-19 pandemic. The increase in smart device usage underscores the pandemic’s far-reaching impact on children’s daily routines and suggests a need for further research into its long-term effects. The findings highlight the importance of considering external societal changes when analyzing trends in digital media usage among children.

Objective: The coronavirus disease-2019 (COVID-19) pandemic has significantly altered daily life, potentially impacting children’s digital media usage. This study investigates changes in smart device usage among children in South Korea, considering the pandemic’s effects. Methods: A longitudinal analysis was conducted on a cohort of 313 children aged 8–11 years from 2018 to 2021. The study measured weekly usage of personal computers (PCs), tablet PCs, and smartphones, comparing pre-pandemic (up to 2020) and post-pandemic periods. Partial correlation analysis was employed to assess the impact of COVID-19, controlling for covariates such as age, household income, and parental education. Results: The analysis revealed a significant increase in smart device usage time following the onset of the pandemic. This increase remained statistically significant even after accounting for covariates. Notably, both age and maternal education level were significant factors influencing device usage. Conclusion This study demonstrates a significant shift in the digital behavior of children aged 8–11 in the context of the COVID-19 pandemic. The increase in smart device usage underscores the pandemic’s far-reaching impact on children’s daily routines and suggests a need for further research into its long-term effects. The findings highlight the importance of considering external societal changes when analyzing trends in digital media usage among children.

Human pluripotent stem cells (hPSCs) can be used to investigate hematopoietic development and have the potential to advance cell-based therapies and to facilitate developmental biology studies. However, efficient ex vivo differentiation into hematopoietic lineages, including red blood cells (RBCs) of the erythroid lineage and immune cells such as macrophages of the myeloid lineage, is hampered by the need for precise temporal regulation of cytokines and growth factors.In this study, we developed an optimized protocol for hematopoietic lineage specification from hPSCs by fine-tuning the temporal dynamics of cytokine and growth factor applications. Prolonged mesodermal specification in the absence of hemogenic cytokines significantly enhanced the generation of hematopoietic progenitors (CD34＋ CD45＋ ) with robust functional potential. Early administration of interleukin (IL)-3 during hematopoietic specification promoted progenitor expansion and maturation. Supplementation of bone morphogenetic protein 4 at the hematopoietic maturation stage enhanced the differentiation efficiency and preferentially drove myeloid lineage commitment toward macrophages at the expense of erythroid differentiation. The timing of erythropoietin administration was important in erythroid lineage commitment, and delayed treatment (day 10) enhanced erythroblast expansion and RBC production. By contrast, the timing of IL-6, GM-CSF, and M-CSF exposure did not significantly affect macrophage differentiation efficiency, suggesting that myeloid lineage specification follows a default pathway under optimized differentiation conditions. These findings suggest a refined, time-controlled strategy for directing hematopoietic differentiation from hPSCs, and provide insight into therapeutic blood cell production, regenerative medicine, and ex vivo modeling of hematopoietic disorders.

Purpose: We investigated the effects of cold water immersion (CWI) treatment during half-time break on performance related physiological indices during second half soccer match. Methods: Twenty-two collegiate soccer players participated in the study. Subjects undertook 3 minutes head out seated with whole body immersion at 19 o C to 21 o C. Total four venous blood samples were collected and analyzed for markers of ionic regulations and inflammatory (interleukin [IL]-1b, IL-6, IL-8, IL-10, tumor necrosis factor-α , and vascular endothelial growth factor) and immune functions (immunoglobulin [Ig] G, IgG2, IgG2, IgG3, IgG4, IgA, and IgM). Results: Partial oxygen concentration and %SO 2 level was lowered in CWI. Hemoglobin and hematocrit values were not significantly different between experimental groups. While there was no notable effect was shown in Na ＋ and Ca 2＋ , K ＋ concentration was higher in CWI during second half match. There were no effects in any of inflammatory and/or anti-inflammatory cytokines and Ig. Conclusion These results suggest that CWI during half time break exert positively affects in buffering capacity and promote oxygen delivery to the actively recruited skeletal muscle, possibly results in improve soccer performance during second half match.

PURPOSE: The aim of this study was to investigate the changes of contraction patterns and the differences of activities in trunk muscles during dynamic balance (multidirectional tilting exercise). METHODS: Eight physically active male subjects participated in the study. Tilting exercises were included by four directions (i.e., forward, backward, left, and right side), and were undertaken at three different tilting degrees (i.e., 10°, 20°, and 30°). They performed two occasions of tilting exercise, separated by 6-week time interval. Surface electromyography system was used for record of any signals produced by muscles which normalized as percentage of maximum voluntary isometric contraction. RESULTS: There were no statistically significant different interactive effects in any of muscles between two factors (time vs. degree). However, we identified significant main effects of degrees (among 10°, 20°, and 30°) in muscle activations during maintaining with forward tilting (left and right longissimus, multifidus), backward tilting (left and right rectus abdominis, external oblique), left side tilting (right rectus abdominis, external oblique, longissimus, multifidus), right side tilting (left rectus abdominis, external oblique, longissimus, multifidus). CONCLUSION: Findings from this study allow the multidirectional tilting exercise to be considered as suitable for ameliorate muscle balance by inducing co-contraction in trunk muscles.
Electromyography ; Exercise ; Humans ; Isometric Contraction ; Male ; Muscles ; Rectus Abdominis