Depressive symptoms and neuroticism mediate the association between traumatic events and suicidality - A latent class mediation analysis of UK Biobank Database.

BACKGROUND: Mental disorders that follow traumatic experience may increase risk of suicidality, but a comprehensive approach to understand how these mental disorders mediate the association between psychological traumatic experience and suicidality should be elucidated. In this study, we attempted to provide comprehensive evidence on how depressive symptoms and neuroticism can mediate the association between psychological traumatic experiences and suicidal behaviours including suicidal ideation, suicidal planning, and suicide attempts. METHODS: We analyzed 111,931 participants from UK Biobank who had completed mental health web-based questionnaire from 2016 to 2017. "Self-harm and suicidal behaviour and ideation (SSBI) score" was calculated by the response from suicidal behaviours and self-harm questionnaires. Conducting multivariate linear regression, depressive symptoms, anxiety symptoms, and neuroticism were selected as potential mediators. We constructed a latent class mediation model estimated direct effect of psychological traumatic events on suicidality and indirect effect of psychological traumatic events mediated by depressive symptoms and neuroticism. RESULTS: Psychological traumatic events were positively associated with suicidal behaviours. Depressive symptoms and neuroticism significantly mediated the effect of psychological traumatic events on suicidality. Anxiety symptoms did not mediate the association between psychological traumatic events and suicidality. CONCLUSION: Psychological traumatic events, irrespective of life stage of occurrence, are associated with suicidality. The association between psychological traumatic events and suicidality can be partially explained by depressive symptoms and neuroticism of those who were exposed to psychological trauma.

Role of individual deprivation and community-level deprivation on suicidal behaviors: Insights from the UK Biobank study.

Introduction: This study aimed to investigate the impact of individual- and community-level deprivation on suicidal behaviors among community members. Methods: Data from 350,884 UK Biobank participants were employed to construct an individual deprivation index. Absolute poverty was defined as a pre-tax annual household income below £18,000. Predictors for absolute poverty incorporated variables such as sex, ethnicity, type of accommodation, tenure status, number of vehicles owned, educational qualifications, current employment status, and subjective health rating. The individual deprivation index was constructed using a logistic regression model to predict absolute poverty. Townsend Deprivation Index (TDI) was employed to represent community-level deprivation. The associations between the individual deprivation index, TDI, and suicidal behaviors were examined through multivariate linear regression. Interaction analyses were conducted to investigate effect modification. Results: The logistic regression model demonstrated high predictive accuracy for absolute poverty (area under the receiver operating curve = 0.840). The associations between individual deprivation index and suicidal behaviors were observed to be more substantial than those between TDI and suicidal behaviors. A positive interaction between the individual deprivation index and TDI was detected, indicating an amplifying effect of community-level deprivation on the impact of individual-level deprivation on suicidal behaviors. Conclusion: Our study successfully constructed a comprehensive individual deprivation index that could be applied widely to measure individual-level deprivation. Our findings revealed that individual-level deprivation and community-level deprivation have a synergistic effect on suicidal behaviors, underscoring the importance of multilevel interventions in suicide prevention.

A marginal structural model to estimate the effect of antidepressant medication treatment on major cardiovascular events among people with post-traumatic stress disorder.

BACKGROUND: Previous evidence on antidepressant medication and cardiovascular disease (CVD) among patients with posttraumatic stress disorder (PTSD) has been inconclusive. We estimated the association between antidepressant medication and CVD by applying a marginal structural model. METHODS: We analyzed medical utilization records of 27 170 people with PTSD without prior major cardiovascular events in the Korean National Health Insurance Database (NHID). PTSD and CVD were defined in accordance with the recorded ICD-10 diagnostic codes. We acquired information on antidepressant use from the NHID and categorized them by medication type. A composite major adverse cardiovascular events (MACE) outcome was defined as coronary artery disease with revascularization, ischaemic stroke, and/or haemorrhagic stroke. We used inverse probability of treatment weighting to estimate the parameters of a marginal structural discrete-time survival analysis regression model, comparing the resulting estimates to those derived from traditional time-fixed and time-varying Cox proportional hazards regression. We calculated cumulative daily defined doses to test for a dose-response relationship. RESULTS: People exposed to antidepressants showed a higher hazard of MACE [hazard ratio (HR) 1.34, 95% confidence interval (CI) 1.18-1.53]. The estimated effects were strongest for selective serotonin reuptake inhibitors (HR 1.24, 95% CI 1.08-1.44) and TCAs (HR 1.33, 95% CI 1.13-1.56). Exposure to serotonin-norepinephrine reuptake inhibitors did not appear to increase the risk of MACE. People exposed to higher doses of antidepressants showed higher risk of MACE. CONCLUSIONS: In a national cohort of people with PTSD, exposure to antidepressant medications increased the risk of MACE in a dose-response fashion.

A Study on the Relationship between Internet Overdependence and Anger Response among Young Adults during COVID-19 Pandemic: Moderating Effect on Negative Emotions.

The aim of this study is to examine how Internet dependence affects anger responses during the COVID-19 pandemic. Owing to social distancing policies, Internet dependence has intensified, and the prevalence of anger has significantly increased. To understand this phenomenon and draw some implications, the "frustration-aggression hypothesis" was utilized for the theoretical framework and anger response was categorized into functional and dysfunctional anger responses. An analysis shows that overdependence on the Internet has a positive effect on the dysfunctional anger response. At the same time, other negative emotions replace anger, reducing the possibility of a dysfunctional anger response. Accordingly, a need for a constant effort to understand the circumstances of the young generation living in the "new normal" is emphasized; moreover, this paper suggests some theoretical and practical implications.

Nonpharmaceutical interventions reduce the incidence and mortality of COVID-19: A study based on the survey from the International COVID-19 Research Network (ICRN).

The recently emerged novel coronavirus, "severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)," caused a highly contagious disease called coronavirus disease 2019 (COVID-19). It has severely damaged the world's most developed countries and has turned into a major threat for low- and middle-income countries. Since its emergence in late 2019, medical interventions have been substantial, and most countries relied on public health measures collectively known as nonpharmaceutical interventions (NPIs). We aimed to centralize the accumulative knowledge of NPIs against COVID-19 for each country under one worldwide consortium. International COVID-19 Research Network collaborators developed a cross-sectional online survey to assess the implications of NPIs and sanitary supply on the incidence and mortality of COVID-19. The survey was conducted between January 1 and February 1, 2021, and participants from 92 countries/territories completed it. The association between NPIs, sanitation supplies, and incidence and mortality were examined by multivariate regression, with the log-transformed value of population as an offset value. The majority of countries/territories applied several preventive strategies, including social distancing (100.0%), quarantine (100.0%), isolation (98.9%), and school closure (97.8%). Individual-level preventive measures such as personal hygiene (100.0%) and wearing facial masks (94.6% at hospitals; 93.5% at mass transportation; 91.3% in mass gathering facilities) were also frequently applied. Quarantine at a designated place was negatively associated with incidence and mortality compared to home quarantine. Isolation at a designated place was also associated with reduced mortality compared to home isolation. Recommendations to use sanitizer for personal hygiene reduced incidence compared to the recommendation to use soap. Deprivation of masks was associated with increased incidence. Higher incidence and mortality were found in countries/territories with higher economic levels. Mask deprivation was pervasive regardless of economic level. NPIs against COVID-19 such as using sanitizer, quarantine, and isolation can decrease the incidence and mortality of COVID-19.

Urbanicity, posttraumatic stress disorder, and effect modification by socioeconomic position: A nested case-control study of the Korean National Health Insurance Database.

BACKGROUND: We aimed to estimate the association between urbanicity and the onset of posttraumatic stress disorder (PTSD) and to investigate heterogeneity therein according to age and socioeconomic position (SEP). METHODS: We analyzed administrative data from the Korean National Health Insurance Database for patients with PTSD from 2004 to 2018 (N = 109,230) and for a 1:4 sample of age-, sex-, and enrollment year-matched controls. Information on eligibility, SEP (proxied by insurance premium), place of residence, diagnosis, and medical claims was obtained. Urbanicity of administrative districts was assessed using data from the Korean Statistical Information Service, 2005-2018. We estimated hazard ratios (HRs) from baseline and time-dependent models. Subgroup analyses and polynomial splines were used to investigate heterogeneity by age and SEP. RESULTS: Urbanicity was associated with an increased risk of PTSD (per 10%p increase, HR = 1.056, 95% CI 1.050-1.061). A positive association was estimated among patients aged 0-29 years (HR = 1.115, CI 1.106-1.124), while negative associations were estimated among patients aged 30-64 years (HR = 0.990, CI 0.987-0.994) and 65 years or older (HR = 0.992, CI 0.979-1.014). The estimated associations with urbanicity were more prominent at the extremes of SEP, but only among younger participants. CONCLUSION: Urban residence was associated with an increased risk of PTSD diagnosis. The estimated association was larger among younger individuals (but not among middle-aged and older individuals). Among younger individuals, the estimated association was larger at both extremes of SEP.

The Relationship Between Thiamine Intake and Long Sleep Duration: Results From the Korea National Health and Nutrition Examination Survey.

OBJECTIVES: Thiamine is thought to modify sleeping patterns, while alcohol use diminishes internal thiamine levels. We investigated the association between thiamine intake and sleep duration and explored possible heterogeneity in the effect according to alcohol use. METHODS: In total, 15 384 participants aged 19-64 were obtained from the Korea National Health and Nutrition Examination Survey 2012-2016. Nutrient intake, including thiamine, was measured using a food frequency questionnaire. Sleep duration was measured by a self-reported questionnaire. The highest thiamine intake quartile was set as the reference group. Participants were divided into 3 groups, with 7-8 hours of daily sleep as a reference group and those who slept more or less than that as "oversleeping" and "insufficient sleeping," respectively. Multivariate logistic regression was used, adjusting for socioeconomic, medical, and nutritional factors. Additionally, participants were stratified according to high-risk alcohol use defined by the World Health Organization standards on alcohol use. RESULTS: Low thiamine intake was associated with oversleeping (Q3: odds ratio [OR], 1.06; 95% confidence interval [CI], 0.86 to 1.32; Q2: OR, 1.24; 95% CI, 0.99 to 1.55; Q1: OR, 1.49; 95% CI, 1.16 to 1.91) and showed a significant trend for higher ORs at lower intake levels (p-trend<0.001). The effect was stronger in the high-risk alcohol use group (Q1: OR, 1.78; 95% CI, 1.28 to 2.49). CONCLUSIONS: Low thiamine intake was associated with oversleeping, and alcohol use intensified that association. These results were found in a context where overt clinical symptoms due to thiamine deficiency are considered rare. More awareness of the potential relationship of thiamine intake with oversleeping and its related risks should be considered.

Development and application of survey-based artificial intelligence for clinical decision support in managing infectious diseases: A pilot study on a hospital in central Vietnam.

Introduction: In this study, we developed a simplified artificial intelligence to support the clinical decision-making of medical personnel in a resource-limited setting. Methods: We selected seven infectious disease categories that impose a heavy disease burden in the central Vietnam region: mosquito-borne disease, acute gastroenteritis, respiratory tract infection, pulmonary tuberculosis, sepsis, primary nervous system infection, and viral hepatitis. We developed a set of questionnaires to collect information on the current symptoms and history of patients suspected to have infectious diseases. We used data collected from 1,129 patients to develop and test a diagnostic model. We used XGBoost, LightGBM, and CatBoost algorithms to create artificial intelligence for clinical decision support. We used a 4-fold cross-validation method to validate the artificial intelligence model. After 4-fold cross-validation, we tested artificial intelligence models on a separate test dataset and estimated diagnostic accuracy for each model. Results: We recruited 1,129 patients for final analyses. Artificial intelligence developed by the CatBoost algorithm showed the best performance, with 87.61% accuracy and an F1-score of 87.71. The F1-score of the CatBoost model by disease entity ranged from 0.80 to 0.97. Diagnostic accuracy was the lowest for sepsis and the highest for central nervous system infection. Conclusion: Simplified artificial intelligence could be helpful in clinical decision support in settings with limited resources.

The Impact of Social Supports on the Excessive Alcohol Use of the Middle-Aged Adults in South Korea: Do All Types of Social Supports Have Positive Effects on Excessive Alcohol Users?

The purpose of the study is to discuss the necessity of interventions on excessive alcohol use among middle-aged adult Koreans and attempt to investigate the effect of social supports including family support and friend support on excessive alcohol use. To achieve these goals, a self-administered online survey was conducted on middle-aged adult Koreans from 40 to 59 years old sampled through the convenience allocation extraction method, with responses of a total of 767 samples analyzed. The results from the analysis was that the support of the family reduced excessive alcohol use, whereas the support of friends provoked excessive alcohol use. Based on these results, the necessity of a distinction in the different types of social supports for interventions in excessive alcohol use was revealed. In addition, several practical and political implications for the alleviation of excessive alcohol use among middle-aged adults are recommended.

Posttraumatic stress disorder, cardiovascular disease outcomes and the modifying role of socioeconomic status.

INTRODUCTION: Substantial evidence indicates that post-traumatic stress disorder (PTSD) is associated with an increased incidence of cardiovascular disease (CVD), and differential PTSD-CVD association by socioeconomic status had been suggested. However, there are inadequate evidence on differential association. This study investigated sociodemographic heterogeneity in the association between PTSD and CVD. METHODS: A total of 53,749 patients diagnosed with PTSD in 2004-2018 were recruited from Korean National Health Insurance Database. Date of first diagnosis of PTSD was set as an index date. We recruited 3 controls per each patient, matched by age and sex (N = 161,247). Monthly insurance premiums were used as a surrogate variable for socioeconomic status. Cox proportional hazard model was used to estimate the hazard of incident coronary artery disease, incident stroke, and cardiovascular mortality. We stratified participants by age, sex, and insurance premium to test heterogeneities in the association. RESULTS: PTSD was associated with increased risk for coronary artery disease, hemorrhagic stroke, and cardiovascular mortality. Elevation in risk of cardiovascular disease was more prominent in younger individuals. PTSD increased the risk of coronary artery disease and ischemic stroke more in individuals with lower SES, especially in men. LIMITATIONS: Insurance premium might not fully represent socioeconomic status of individual. Misclassification or misdiagnosis of PTSD by might have introduced biases. CONCLUSIONS: PTSD was associated with increased incidence of CVD, particularly in male patients with low SES. For PTSD patients with lower SES, preventive measures against cardiovascular disease would be able to decrease the disease burden of cardiovascular comorbidity in PTSD.

Evaluation of radiation dose to organs of neonatal patients during portable X-ray examination in incubators: A Monte Carlo simulation study.

BACKGROUND: Infants admitted to neonate intensive care units (NICUs) are placed in incubators to maintain body temperature and condition, which undergo normal radiographs and are exposed to radiation. Furthermore, different incubator structures in different hospitals exhibit varying object to image receptor distance (OID), source to image receptor distance (SID), presence of canopy, which results in variations in X-ray radiation conditions and doses absorbed by the neonatal patients. OBJECTIVE: To measure organ dose exposed to neonatal patient in different incubator settings. METHODS: A portable X-ray was performed on a neonatal patient placed in an incubator to identify disease progress, the injection path of the drug, and various factors. To minimize direct contact between neonatal patients and image receptor, radiologic technologists place the image receptor on a tray underneath the incubator and place the portable X-ray tube on top of the acrylic canopy of the incubators. SID and OID settings and value of organ dose exposed to the patient varied based on the incubator structure, and the organ absorbed dose was determined using Monte Carlo N-Particle (MCNP) simulation, PC-based Monte Carlo program (PCXMC) 2.0 simulation, and neonate phantoms. RESULTS: Evaluations of organ dose of neonatal patients in three hospitals with different incubator settings reveal that the average organ dose differs by 36% depending on change in OID and SID settings and reduces by 10% with an acrylic canopy. Therefore, owing to the presence of an acrylic canopy on the top of the incubator and the longer SID with the corresponding shorter OID, a lower dose was absorbed by organs of neonatal patient. CONCLUSION: Our results provide proof that proper incubator standard decreases organ dose to neonatal patient during continuously diagnostic X-ray procedure.

Size Effect of a Piezoelectric Material as a Separator Coating Layer for Suppressing Dendritic Li Growth in Li Metal Batteries.

Li metal has been intensively investigated as a next-generation rechargeable battery anode. However, its practical application as the anode material is hindered by the deposition of dendritic Li. To suppress dendritic Li growth, introducing a modified separator is considered an effective strategy since it promotes a uniform Li ion flux and strengthens thermal and mechanical stability. Herein, we present a strategy for the surface modification of separator, which involves coating the separator with a piezoelectric material (PM). The PM-coated separator shows higher thermal resistance than the pristine separator, and its modified surface properties enable the homogeneous regulation of the Li-ion flux when the separator is punctured by Li dendrite. Furthermore, PM was synthesized in different solvents via solvothermal method to explore the size effect. This strategy would be helpful to overcome the intrinsic Li metal anode problems.

Plasma osteoprotegerin levels are associated with the presence and burden of cerebral small vessel disease in patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: Osteoprotegerin (OPG) is a component of the tumor necrosis factor receptor superfamily. Several studies have shown a relationship between OPG and cardiovascular diseases. We hypothesized that there is a relationship between plasma OPG levels and cerebral small vessel disease (SVD). METHODS: Patients diagnosed with their first cerebral ischemic infarction between April 2014 and March 2017 were enrolled. All the enrolled patients were evaluated through the hospital stroke protocol, including routine blood tests, brain imaging, and measuring the plasma OPG levels. The presence and burden of cerebral SVD [cerebral microbleeds (CMBs), asymptomatic lacunar infarction (ALI), high-grade perivascular space (HPVS), high-grade white matter hyperintensity (HWMH)], and total SVD score were assessed through brain magnetic resonance imaging. RESULTS: Of the 270 patients included in our study, 158 (58.5%) were men. The mean age of the patients was 63.8 ± 11.6 years. In multivariable analysis, plasma OPG levels were positively associated with the presence and burden of each cerebral SVD. The odds ratios (OR) of CMBs, ALI, HPVS, and HWMH for the association of OPG per standard deviation (SD) increase were 1.58 [95% confidence interval (CI), 1.09-2.27], 1.40 (95% CI, 1.04-1.88), 1.88 (95% CI, 1.27-2.78), and 1.47 (95% CI, 1.04-2.08), respectively. Plasma OPG levels were positively correlated with total SVD score (beta = 0.211, standard error = 0.061, p-value = 0.009, R2 = 0.275). CONCLUSIONS: Plasma OPG levels correlate with the presence and burden of cerebral SVD in patients with acute ischemic stroke.

Effect of chemotherapy and radiotherapy on cognitive impairment in colorectal cancer: evidence from Korean National Health Insurance Database Cohort.

OBJECTIVES: We investigated the risk of chemotherapy-related and radiotherapy-related cognitive impairment in colorectal cancer patients. METHODS: Medical use data of colorectal cancer patients were obtained from the Korean National Health Insurance Database from 2004 to 2018. We randomly selected 40% of all colorectal cancer patients (n=148,848). Cognitive impairment was defined as having 1 or more International Classification of Diseases, 10th revision diagnostic codes for dementia or mild cognitive impairment. Patients aged 18 years or younger, patients diagnosed with cognitive impairment before colorectal cancer diagnosis (n=8,225), and patients who did not receive primary resection (n=45,320) were excluded. The effects of individual chemotherapy regimens on cognitive impairment were estimated. We additionally estimated the effect of radiotherapy in rectal cancer patients. Time-dependent competing risk Cox regression was conducted to estimate the overall and age-specific hazard ratios (HR) separately for colon and rectal cancer. Landmark analyses with different lag times were conducted as sensitivity analyses. RESULTS: Chemotherapy did not increase the risk of cognitive impairment in colorectal cancer patients (colon cancer: HR, 0.92; 95% confidence interval [CI], 0.83 to 1.03; rectal cancer: HR, 0.88; 95% CI, 0.75 to 1.04), while radiotherapy was negatively associated with cognitive impairment in rectal cancer patients (HR, 0.01; 95% CI, 0.84 to 0.99). Varying directions of the associations between regimens and cognitive impairment were detected. The adverse effect of certain chemotherapy regimens on cognition was more prominent in older adults. CONCLUSIONS: Chemotherapy and radiotherapy did not increase the risk of cognitive impairment. Older patients with low cognitive reserve could be affected by the adverse cognitive effects of chemotherapy.

The effects of information-seeking behaviours on prevention behaviours during the COVID-19 pandemic: the mediating effects of anxiety and fear in Korea.

OBJECTIVES: Identifying determinants of prevention behaviours during the emergence of a new infectious disease is important. We investigated the associations between information-seeking and prevention behaviours during the coronavirus disease 2019 (COVID-19) pandemic and mediating effects of psychiatric factors. METHODS: In total, 1,970 participants from the Cardiovascular and Metabolic Etiology Research Center cohort participated in an online survey 55 days after the first COVID-19 case in Korea was diagnosed. Time spent seeking information related to COVID-19; information sources; psychiatric factors, including anxiety, depression, post-traumatic stress symptoms (PTSS), and the fear of COVID-19; and prevention behaviours were examined. The mediating effect of psychiatric factors was estimated using mediation analysis. RESULTS: Time spent seeking information and information sources affected several behavioural responses. In men, anxiety mediated associations between information-seeking and prevention behaviours, including purchasing sanitary supplies (effect size [ES], 0.038; 95% confidence interval [CI], 0.002 to 0.095) and hoarding (ES, 0.029; 95% CI, 0.002 to 0.068). The fear of COVID-19 also mediated associations between information-seeking and prevention behaviours including refraining from going out (men: ES, 0.034; 95% CI, 0.009 to 0.068; women: ES, 0.052; 95% CI, 0.030 to 0.080), wearing face masks (men: ES, 0.085; 95% CI, 0.031 to 0.184), avoiding public transportation (men: ES, 0.020; 95% CI, 0.000 to 0.044; women: ES, 0.031; 95% CI, 0.015 to 0.051), hoarding (women: ES, 0.051; 95% CI, 0.029 to 0.792), and trying alternative remedies (men: ES, 0.024; 95% CI, 0.004 to 0.053). Depressive symptoms and PTSS did not have any mediating effects. CONCLUSIONS: While the availability of information related to COVID-19 can help prevent infections, it can also promote anxiety and fear, leading to negative behaviours such as hoarding and trying unverified alternative treatments.

Impact of COVID-19 on mental health according to prior depression status: A mental health survey of community prospective cohort data.

OBJECTIVE: We aimed to investigate the mental health impact of COVID-19 on a demographically well-characterized population cohort by gender and previous depression status. METHODS: Among people who participated in a community cohort study between 2013 and 2018 with previous depression measurement, a total of 1928 people without quarantine experience (680 men and 1249 women) were included after responding to an online survey in March 2020. In the 2020 survey, people were queried about daily needs supply, social support, risk perception, change during the COVID-19 pandemic, as well as mental health indices measuring loneliness, anxiety symptoms, post-traumatic stress disorder (PTSD), and depression. Separate analyses by gender were conducted to assess the association between COVID-19-related experiences and each mental health index, using multivariable logistic regressions with additional adjustment and stratification with pre-existing depression status. RESULTS: We could not observe significant gender differences for depression, anxiety, PTSD, and loneliness at 55 days after the start of the COVID-19 outbreak. Most external support, including daily needs supply and social support, protected men and women from experiencing severe anxiety (for life supply, OR = 0.92 (95%CI 0.88-0.97) (men) and OR = 0.95 (95% CI 0.91-0.99) (women); for social support, OR = 0.92(both for men and women, p < 0.01)). The results were similar for depression and PTSD. External support showed a larger reduction in the likelihoods for anxiety and depression during the COVID-19 pandemic among people with pre-existing depression compared to previously healthy people, and it was more prominent in men. CONCLUSION: COVID-19 significantly affected the mental health of both men and women in the early period of the pandemic. Having enough supply of daily needs and social support seems important, especially for people with previous depression.

Voltage-Tunable Ultra-Steep Slope Atomic Switch with Selectivity over 1010.

Atomic switch-based selectors, which utilize the formation of conductive filaments by the migration of ions, are researched for cross-point array architecture due to their simple structure and high selectivity. However, the difficulty in controlling the formation of filaments causes uniformity and reliability issues. Here, a multilayer selector with Pt/Ag-doped ZnO/ZnO/Ag-doped ZnO/Pt structure by the sputtering process is presented. A multilayer structure enables control of the filament formation by preventing excessive influx of Ag ions. The multilayer selector device exhibits a high on-current density of 2 MA cm-2 , which can provide sufficient current for the operation with the memory device. Also, the device exhibits high selectivity of 1010 and a low off-current of 10-13 A. The threshold voltage of selector devices can be controlled by modulating the thickness of the ZnO layer. By connecting a multilayer selector device to a resistive switching memory, the leakage current of the memory device can be reduced. These results demonstrate that a multilayer structure can be used in a selector device to improve selectivity and reliability for use in high-density memory devices.

Associations Between General Perceptions of COVID-19 and Posttraumatic Stress Disorder in Korean Hospital Workers: Effect Modification by Previous Middle East Respiratory Syndrome Coronavirus Experience and Occupational Type.

OBJECTIVES: This study investigated associations between perceptions of coronavirus disease 2019 (COVID-19) and the prevalence of posttraumatic stress disorder (PTSD) in workers at hospitals designated to treat COVID-19, as well as the difference in the magnitude of these associations by occupational type and previous Middle East respiratory syndrome coronavirus (MERS-CoV) experience. METHODS: The participants were workers at hospitals designated to treat COVID-19 who completed a questionnaire about their perceptions related to COVID-19, work experience during the previous MERS-CoV outbreak, and symptoms of PTSD ascertained by the PTSD Checklist for the Diagnostic and Statistical Manual of Mental Disorders. Participants' characteristics were compared using the chi-square test. Multivariable logistic regression was performed to evaluate the associations between perceptions and the prevalence of PTSD, stratified by occupational type and previous MERS-CoV experience. RESULTS: Non-medical personnel showed stronger associations with PTSD than medical personnel according to general fear (odds ratio [OR], 6.67; 95% confidence interval [CI], 1.92 to 23.20), shortages of supplies (OR, 1.29; 95% CI, 1.07 to 1.56), and issue-specific fear (OR, 1.29; 95% CI, 1.05 to 1.59). Those with prior MERS-CoV quarantine experience were more prone to PTSD than those without such experience in terms of general fear (OR, 1.70; 95% CI, 1.22 to 2.37), shortages of supplies (OR, 1.24; 95% CI, 1.10 to 1.40), and issue-specific fear (OR, 1.21; 95% CI, 1.06 to 1.38). CONCLUSIONS: During the COVID-19 pandemic, non-medical personnel tended to have higher odds of being categorized as having PTSD. Workers with prior MERS-CoV experience were more susceptible than those without such experience. These findings suggest the need for timely interventions to manage human resources for a sustainable quarantine system.

Neurocognitive Effects of Chemotherapy for Colorectal Cancer: A Systematic Review and a Meta-Analysis of 11 Studies.

PURPOSE: Chemotherapy-related cognitive impairment (CRCI) is a controversial concept not much explored on colorectal cancer patients. MATERIALS AND METHODS: We identified 11 prospective studies: eight studies on 696 colorectal cancer patients who received chemotherapy and three studies on 346 rectal cancer patients who received neoadjuvant chemoradiotherapy. Standardized mean differences (SMDs) of neuropsychological test results and the cognitive quality-of-life scale were calculated using random effect models. A meta-regression was conducted to investigate the association between mean study population age and effect sizes. RESULTS: The association between chemotherapy and cognitive impairment was not clear in colorectal cancer patients (SMD, 0.003; 95% confidence interval, ‒0.080 to 0.086). However, a meta-regression showed that older patients are more vulnerable to CRCI than younger patients (ß=‒0.016, p < 0.001). CONCLUSION: Chemotherapy has an overall positive negligible effect size on the cognitive function of colorectal patients. Age is a significant moderator of CRCI.

Associations between social network properties and metabolic syndrome and the mediating effect of physical activity: findings from the Cardiovascular and Metabolic Diseases Etiology Research Center (CMERC) Cohort.

INTRODUCTION: Social isolation and loneliness are positively associated with metabolic syndrome. However, the mechanisms by which social isolation affects metabolic syndrome are not well understood. RESEARCH DESIGN AND METHODS: This study was designed as a cross-sectional study of baseline results from the Cardiovascular and Metabolic Diseases Etiology Research Center (CMERC) Cohort. We included 10 103 participants (8097 community-based low-risk participants, 2006 hospital-based high-risk participants) from the CMERC Cohort. Participants aged 65 years or older were excluded. Multiple imputation by chained equations was applied to impute missing variables. The quantitative properties of social networks were assessed by measuring the 'size of social networks'; qualitative properties were assessed by measuring the 'social network closeness'. Metabolic syndrome was defined based on the National Cholesterol Education Program Adult Treatment Panel III criteria. Multivariate logistic regression analyses were conducted to assess association between social network properties and metabolic syndrome. The mediating effects of physical inactiveness, alcohol consumption, cigarette smoking and depressive symptoms were estimated. Age-specific effect sizes were estimated for each subgroup. RESULTS: A smaller social network was positively associated with higher prevalences of metabolic syndrome in all subgroups, except the high-risk male subgroup. There was no clear association between social network closeness and metabolic syndrome. In community-based participants, an indirect effect through physical activity was detected in both sexes; however, in hospital-based participants, no indirect effects were detected. Cigarette smoking, alcohol consumption and depression did not mediate the association. Age-specific estimates showed that the indirect effect through physical activity had a greater impact in older participants. CONCLUSIONS: A smaller social network is positively associated with metabolic syndrome. This trend could be partially explained by physical inactivity, especially in older individuals.