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Metal‐free, visible‐light‐induced site‐selective heteroarylation of remote C(sp3)−H bonds has been accomplished through the design of N‐alkoxyheteroarenium salts serving as both alkoxy radical precursors and heteroaryl sources. The transient alkoxy radical can be generated by the single‐electron reduction of an N‐alkoxypyridinium substrate by a photoexcited quinolinone catalyst. Subsequent radical translocation of the alkoxy radical forms a nucleophilic alkyl radical intermediate, which undergoes addition to the substrate to achieve remote C(sp3)−H heteroarylation. This cascade strategy provides a powerful platform for remote C(sp3)−H heteroarylation in a controllable and selective manner and is well suited for late‐stage functionalization of complex bioactive molecules. [ABSTRACT FROM AUTHOR]

Intact cognitive control is critical for goal‐directed behavior and is widely studied using the error‐related negativity (ERN). A common assumption in such studies is that ERNs recorded during different experimental paradigms reflect the same construct or functionally equivalent processes and that ERN is functionally distinct from other error‐monitoring event‐related brain potentials (ERPs; error positivity [Pe]), other neurophysiological indices of cognitive control (N2), and even other theoretically unrelated indices (visual N1). The present registered report represents a replication‐plus‐extension study of the psychometric validity of cognitive control ERPs and evaluated the convergent and divergent validity of ERN, Pe, N2, and visual N1 recorded during flanker, Stroop, and Go/no‐go tasks. Data from 182 participants were collected from two study sites, and ERP psychometric reliability and validity were evaluated. Findings supported replication of convergent and divergent validity of ERN, Pe, and ΔPe (error minus correct)—these ERPs correlated more with themselves across tasks than with other ERPs measured during the same task. Convergent validity of ΔERN across tasks was not replicated, despite high internal consistency. ERN strongly correlated with N2 at levels similar or higher than those in support of convergent validity for other ERPs, and the present study failed to provide evidence of divergent validity for ERN and Pe from N2 or N1. ERN and ΔERN were unrelated to internalizing or externalizing symptoms. Findings underscore the importance of considering the psychometric validity of ERPs, as it provides a foundation for interpreting and comparing ERPs across tasks and studies. [ABSTRACT FROM AUTHOR]

Background: Evidence suggests that low individual vitamin D levels enhance adverse effects associated with air pollution on mental health conditions. The aim of this study was to identify associations between ambient air pollution exposure, mental health, and serum vitamin D status in the general population of South Korea.Methods: We included national representative data for 29,373 adults in the final analysis. We measured serum 25-hydroxyvitamin D concentrations to assess vitamin D status for each participant. We assessed mental health factors (i.e., perceived stress, depressive symptoms, and suicidal ideation), and analyzed associations between these factors and individuals' annual average exposures to air pollutants, including particulate matter with an aerodynamic diameter ≤ 10 μm (PM10), nitrogen dioxide (NO2), sulfur dioxide, and carbon monoxide (CO).Results: Using an adjusted model, we found PM10 affected mental health outcomes, such as perceived stress (odds ratio [OR] = 1.04; 95 % confidence interval [CI] = 1.00-1.09), depression symptoms (OR = 1.12; 95 % CI = 1.06-1.18), and suicidal ideation (OR = 1.11; 95 % CI = 1.05-1.17). Effects of the pollutants NO2 and CO were significant only in the group with perceived stress and depressive symptoms. PM10 and NO2 exposures were significantly associated with increased odds of adverse mental health in participants with vitamin D deficiency.Limitations: Since the cross-sectional design of KNHANES data, it is not possible to evaluate the causal relationship between air pollution exposure, vitamin D status and mental health.Conclusions: This study results suggest that associations between ambient air pollution and mental health outcomes were stronger in participants with vitamin D deficiency. [ABSTRACT FROM AUTHOR]

Background: Although a growing body of evidence suggests air pollution is associated with low serum vitamin D status, few studies have reported whether obesity status affects this relationship. The aim of this study was to identify associations between ambient air pollution exposure, obesity, and serum vitamin D status in the general population of South Korea.Methods: This study was conducted in a cross-sectional design. A total of 30,242 Korean adults from a nationwide general population survey were included for our final analysis. Air pollutants included particulate matter with an aerodynamic diameter ≤ 10 μm (PM10), nitrogen dioxide (NO2), and carbon monoxide (CO). We measured serum 25-hydroxyvitamin D concentration to assess vitamin D status for each participant. Multiple linear and logistic regression analyses were performed to identify associations between ambient air pollution and vitamin D status in each subgroup according to body mass index level.Results: The annual average concentrations of PM10, NO2, and CO were significantly associated with a lower serum vitamin D concentration and higher risk of vitamin D deficiency. The results show a significant association between serum vitamin D status and PM10 exposure in obese subgroup. Based on the gender, females with obesity showed more strong association (negative) between different air pollutants and low serum vitamin D concentration and a higher risk of vitamin D deficiency. However, this pattern was not observed in men.Conclusions: This study provides the first evidence that women with obesity may be more vulnerable to vitamin D deficiency in the context of persistent exposure to air pollution. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to identify the best-fitting model in predicting the health gap of multimorbid status based on the health gap of uniconditional status.Methods: This study analyzed data of adults aged 50 years or older derived from the cross-sectional, nationally representative 6th Korean National Health and Nutrition Examination Survey (KNHANES). We translated the EQ-5D utility score assessed from the KNHANES using the Korean EQ-5D-3L into the health gap by subtracting the EQ-5D utility score from one. The predicted health gap of multimorbid status was calculated based on the health gap of uniconditional status using the additive, multiplicative, and maximum limit models. We assessed the performance of the multimorbidity adjustment models based on the root mean square error and mean absolute error. We also examined the impact of multimorbidity adjustment on the estimated disease burden in the best-fitting model.Results: Of the three approaches, the multiplicative adjustment model had the smallest root mean square error between the predicted and observed health gap of multimorbid status. The total number of prevalence-based years lived with the disability after adjusting for multimorbid status using the multiplicative model decreased compared to that without adjustment for multimorbid status.Conclusion: Using the appropriate methodology to adjust for multimorbidity in estimations of population health is becoming more important as the prevalence of multimorbidity increases, particularly in older populations. Further empirical research is required to develop additional general adjustment approaches that consider the independent co-occurrence of multiple diseases, and to understand how multimorbidity influences health gap. [ABSTRACT FROM AUTHOR]

Exposure to perfluoroalkyl substances (PFAS) may increase the risk of liver disease by disrupting cholesterol and lipid synthesis/metabolism, leading to higher liver-enzyme concentrations. However, most studies assessing association between PFAS and liver enzymes focused on individual PFAS. Moreover, PFAS concentrations differ based on sex and obesity status, and it remains unclear whether these factors affect associations with liver function. Therefore, we examined the association between exposure to both individual and combined PFAS and liver-function biomarkers and assessed sex and obesity as effect modifiers in Korean adults. We measured serum concentrations of the five most abundant PFAS (PFOA, PFOS, PFHxS, PFDA, PFNA) and three liver enzymes (alanine transaminase [ALT], aspartate aminotransferase [AST], γ-glutamyl transferase [GGT]) in 1404 adults from the Korean National Environmental Health Survey Cycle 3, 2015–2017. We used linear regression to evaluate associations between individual PFAS and liver-function biomarkers, assessing sex and obesity as possible effect modifiers, and performed Bayesian kernel machine regression and quantile g-computation to evaluate the overall effect of PFAS mixture on biomarkers of liver function. Among 1404 Korean adults, all five PFAS were detected. Geometric mean concentration was highest for PFOS (16.11 μg/L), followed by PFOA (5.83 μg/L), PFHxS (2.21 μg/L), PFNA (2.03 μg/L), and PFDA (1.06 μg/L). In multivariable linear regression, all PFAS were positively associated with ALT, AST, and GGT; 2-fold increase in each PFAS was associated with 3.4–8.6% higher ALT, 2.4–4.6% higher AST, and 4.6–11.1% higher GGT (all p < 0.05). Positive associations for PFOA, PFDA, and PFNA with AST were stronger in men, and positive associations for PFOS with ALT and GGT were stronger in women. Compared to obese participants, nonobese participants had higher average percent changes in each enzyme, particularly GGT, when individual PFAS concentration doubled. Additionally, increased exposure to PFAS mixtures was associated with higher ALT, AST, and GGT. In quantile g-computations, simultaneous quartile increase in all PFAS was significantly associated with 6.9% (95%CI: 3.7, 10.2) higher ALT, 4.5% (95%CI: 2.4, 6.6) higher AST, and 8.3% (95%CI: 3.7, 13.1) higher GGT levels, on average. Exposure to individual and combined PFAS is associated with higher liver enzymes in Korean adults, providing additional evidence for the association between PFAS exposure and risk of liver disease. [Display omitted] • Serum concentrations of PFAS were detected in Korean adults. • Higher serum PFOA, PFOS, PFHxS, PFDA, and PFNA concentrations were related to higher serum concentrations of liver enzymes. • Some differences in these associations were observed dependent on sex and obesity. • Overall effect of combined PFAS exposure was positively associated with liver enzyme levels (ALT, AST, and GGT). [ABSTRACT FROM AUTHOR]

Performance monitoring has been widely studied during different forced-choice response tasks. Participants typically show longer response times (RTs) and increased accuracy following errors, but there are inconsistencies regarding the connection between error-related event-related brain potentials (ERPs) and behavior, such as RT and accuracy. The specific task in any given study could contribute to these inconsistencies, as different tasks may require distinct cognitive processes that impact ERP-behavior relationships. The present study sought to determine whether task moderates ERP-behavior relationships and whether these relationships are robustly observed when tasks and stimuli are treated as random effects. ERPs and behavioral indices (RTs and accuracy) recorded during flanker, Stroop, and Go/Nogo tasks from 180 people demonstrated a task-specific effect on ERP-behavior relationships, such that larger previous-trial error-related negativity (ERN) predicted longer RTs and greater likelihood of a correct response on subsequent trials during flanker and Stroop tasks but not during Go/Nogo task. Additionally, larger previous-trial error positivity (Pe) predicted faster RTs and smaller variances of RTs on subsequent trials for Stroop and Go/Nogo tasks but not for flanker task. When tasks and stimuli were treated as random effects, ERP-behavior relationships were not observed. These findings support the need to consider the task used for recording performance monitoring measures when interpreting results across studies., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: The turnover of new and mid-career nurses has been increasing, leading to challenges in recruiting and retaining nursing staff., Objectives: Securing and retaining mid-career nurses is crucial for ensuring high-quality care. However, little is known about mid-career nurses' experiences regarding turnover. This study aimed to understand the experiences of mid-career nurses and identify strategies to enable mid-career nurses to maintain long-term employment in health services., Design: Colaizzi's phenomenological methodology was adopted to illuminate the subjective meaning derived from the work-related challenges of mid-career nurses, leading to turnover. Focus group interviews were conducted to delve into the work challenges faced by mid-career nurses., Method: The participants were 23 mid-career nurses working in one tertiary hospital and six secondary hospitals across three Korean cities, recruited using purposive and snowball sampling. The inclusion criteria entailed a minimum of three years of nursing experience and current employment within a designated department or clinical area within the hospital environment, commonly known as a nursing unit. Such units encompassed a range of clinical settings, including medical-surgical units, intensive care units, and emergency rooms. The interview data were transcribed verbatim, and significant statements were extracted from abstract sentences to derive themes through an analytical process., Results: Analysis of the work experiences of 23 mid-career nurses in medical institutions yielded 15 themes and 4 theme clusters derived from 353 meaningful statements. These theme collections were identified as 'Difficulties endured as a mid-career nurse', 'Meaningless and regrettable new graduate nurses' education', 'An inexpressibly poor work environment', and 'Systems and policies needed to remain in the hospital'., Conclusions: Difficulties faced by mid-career nurses including the establishment of an education and career development system, provisions for guaranteed leave, a diverse and flexible work system, opportunities for effective communication, and engagement with the opinions of mid-career nurses should promptly be addressed.

Background: This study aimed to investigate the trends of aggressive care at the end-of-life (EoL) for patients with advanced cancer in Korea and to identify factors affecting such care analyzing nationwide data between 2012 to 2018., Methods: This was a population-based, retrospective nationwide study. We used administrative data from the National Health Insurance Service and the Korea Central Cancer Registry to analyze 125,350 patients aged 20 years and above who died within one year of a stage IV cancer diagnosis between 2012 and 2018., Results: The overall aggressiveness of EoL care decreased between 2012 and 2018. In patients' last month of life, chemotherapy use (37.1% to 32.3%; p < 0.05), cardiopulmonary resuscitation (13.2% to 10.4%; p < 0.05), and intensive care unit admission (15.2% to 11.1%; p < 0.05) decreased during the study period, although no significant trend was noted in the number of emergency room visits. A steep increase was seen in inpatient hospice use in the last month of life (8.6% to 26.6%; p < 0.05), while downward trends were observed for hospice admission within three days prior to death (13.9% to 11%; p < 0.05). Patients were more likely to receive aggressive EoL care if they were younger, women, had treatment in tertiary hospitals, or had hematologic malignancies. In the subgroup analysis, the overall trend of aggressive EoL care decreased for all five major cancer types., Conclusion: The aggressiveness of EoL care in stage IV cancer patients showed an overall decrease during 2012-2018 in Korea., (© 2024. The Author(s).)

Endocrine-disrupting chemicals (EDCs) may play a role in non-alcoholic fatty liver disease (NAFLD); however, studies on the combined effects of EDC mixtures on NAFLD development are limited. Here, we explored the association between exposure to EDC mixtures and NAFLD and investigated the potential mediating role of metabolic syndrome (MetS). We included participants from the Korean National Environmental Health Survey Cycle 4 (2018-2020) and quantified the urinary concentrations of various EDCs-eight phthalate metabolites, three phenols, one antibacterial compound, four parabens, four polycyclic aromatic hydrocarbons, and one pyrethroid pesticide metabolite-as well as serum concentrations of five perfluorinated compounds (PFCs). NAFLD was defined as a hepatic steatosis index (HSI) ≥36 or a fatty liver index (FLI) ≥60. Weighted quantile sum (WQS) regression was employed to evaluate the associations between EDC mixtures and the risk of MetS or NAFLD. Causal mediation analysis was conducted to explore the potential mediating effect of MetS on the association between mixtures of EDCs and NAFLD risk. All estimates were adjusted for age, sex, educational level, physical activity, smoking status, involuntary smoking, and drinking habits. A total of 2942 adults were included in the analysis. Moderate-to-high positive correlations were identified between phthalate metabolites and PFCs. Higher WQS scores were associated with an elevated risk of MetS and NAFLD. The sex-stratified WQS regression model showed that the interactions between the WQS index and sex were significant for MetS and NAFLD. According to the causal mediation analysis, both the direct and indirect effects of EDC mixtures on NAFLD, with MetS as a mediator, were significant in females. Collectively, these findings highlight the need for interventions that could address both EDC mixture exposure and metabolic status to effectively reduce the risks associated with NAFLD and its related complications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Herein, we describe the synthesis of substituted oxepane derivatives through the skeletal remodeling of 4-hydroxy-2-cyclobutenones, which are readily prepared from commercially available dialkyl squarates upon their reaction with acrylonitrile. Mechanistically, a Rh(I)-catalyzed C-C bond formation and cleavage cascade is proposed. Specifically, a fused [3.2.0] bicycle is proposed to form from dialkyl squarate-derived cyclobutenols via an unusual Rh(I)-catalyzed intermolecular oxa-Michael addition of a tertiary alcohol with acrylonitrile, followed by an intramolecular conjugate addition/migratory insertion. Subsequent C(sp 3 )-C(sp 3 ) bond cleavage through a Rh-catalyzed β-carbon elimination is then theorized to furnish the oxepane scaffold. Computational studies support the formation of an intermediate [3.2.0] bicycle but also point to an alternative pathway for the formation of the oxepane products involving a Rh(III) intermediate. Additional studies have shown the overall process to be stereoretentive. The functional groups that are introduced in this process can be leveraged to form fused or bridged ring systems.

Chiral aziridines are important structural motifs found in natural products and various target molecules. They serve as versatile building blocks for the synthesis of chiral amines. While advances in catalyst design have enabled robust methods for enantioselective aziridination of activated olefins, simple and abundant alkyl-substituted olefins pose a significant challenge. In this work, we introduce a novel approach utilizing a planar chiral rhodium indenyl catalyst to facilitate the enantioselective aziridination of unactivated alkenes. This transformation exhibits a remarkable degree of functional group tolerance and displays excellent chemoselectivity favoring unactivated alkenes over their activated counterparts, delivering a wide range of enantioenriched high-value chiral aziridines. Computational studies unveil a stepwise aziridination mechanism in which alkene migratory insertion plays a central role. This process results in the formation of a strained four-membered metallacycle and serves as both the enantio- and rate-determining steps in the overall reaction.

Background: Various life course factors can affect susceptibility to diseases during adolescence and adulthood, and those relationships are complex. However, few studies have assessed the potential mediating factors. Therefore, we assessed the mediating effects of factors related to growth and inflammation between perinatal factors and metabolic syndrome risk during adolescence., Methods: The study was conducted on adolescents who participated in the follow-up in the Ewha Birth and Growth Cohort. We considered the ponderal index (PI) as a perinatal factor and the continuous metabolic syndrome score (cMetS) as the outcome and confirmed the mediating effects of body mass index (BMI) trajectory pattern in childhood and inflammation levels by using the PROCESS macro for SAS., Results: Although the direct effect of BMI trajectory on the relationship between PI and cMetS was not significant (0.545), the indirect effect was significant (1.044). In addition, the indirect effect was statistically significant in the pathways mediating the BMI trajectory pattern and inflammation (β = 1.456)., Conclusions: The direct and indirect effects on the relationship between PI and cMetS suggest that childhood factors related to growth may be involved in disease susceptibility. Therefore, appropriate interventions for the management of obesity during the growth phase are necessary., Impact: Unlike other existing studies, this study assessed multiple mediating effects by considering the BMI trajectory pattern and inflammatory indexes as mediating factors between the ponderal index and the continuous metabolic syndrome score during adolescence. We found significant indirect effects of the BMI trajectory between PI and cMetS, and also significant indirect effects in the pathways mediating the BMI trajectory and hs-CRP. The significant indirect mediating effects support that childhood factors related to growth may be involved in disease susceptibility., (© 2023. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)

Described herein are studies toward the core modification of cyclic aliphatic amines using either a riboflavin/photo-irradiation approach or Cu(I) and Ag(I) to mediate the process. Structural remodeling of cyclic amines is explored through oxidative C-N and C-C bond cleavage using peroxydisulfate (persulfate) as an oxidant. Ring-opening reactions to access linear aldehydes or carboxylic acids with flavin-derived photocatalysis or Cu salts, respectively, are demonstrated. A complementary ring-opening process mediated by Ag(I) facilitates decarboxylative Csp 3 -Csp 2 coupling in Minisci-type reactions through a key alkyl radical intermediate. Heterocycle interconversion is demonstrated through the transformation of N-acyl cyclic amines to oxazines using Cu(II) oxidation of the alkyl radical. These transformations are investigated by computation to inform the proposed mechanistic pathways. Computational studies indicate that persulfate mediates oxidation of cyclic amines with concomitant reduction of riboflavin. Persulfate is subsequently reduced by formal hydride transfer from the reduced riboflavin catalyst. Oxidation of the cyclic aliphatic amines with a Cu(I) salt is proposed to be initiated by homolysis of the peroxy bond of persulfate followed by α-HAT from the cyclic amine and radical recombination to form an α-sulfate adduct, which is hydrolyzed to the hemiaminal. Investigation of the pathway to form oxazines indicates a kinetic preference for cyclization over more typical elimination pathways to form olefins through Cu(II) oxidation of alkyl radicals.

Background: Phthalate exposure is ubiquitous due to the widespread use of plastic products in daily life, and affects several health outcomes, including metabolic diseases. In this study, we evaluated the effects of phthalate exposure in childhood on liver function in adolescence.  METHODS: Among 164 Ewha Birth and Growth Cohort Study participants followed up during two exposure periods (when the children were aged 3-5 and 7-9 years), 126 were followed up at age 10-15 years. To investigate the relationship between phthalate exposure during the two periods and liver enzyme levels (ALT, AST, γ-GTP) in adolescence, differences between groups and the dose-response relationship were analyzed. In addition, we investigated differences in liver enzymes between groups based on the combined exposure levels (high or low) during the two periods. The interaction effect between phthalates and BMI on liver enzyme levels was evaluated, stratified by sex.  RESULTS: In the 3-5 year-old exposure period, ALT levels tended to increase as MECPP levels increased, while γ-GTP levels tended to increase as MiBP, MnBP, and ∑DBP levels increased. In addition, the group exposed to consistently high levels of phthalates at both time points had higher liver enzyme levels compared to the group that had lower exposure. In particular, the interaction effect between some phthalate metabolites and BMI in 3-5 year olds affected AST and γ-GTP levels in adolescence only in girls., Conclusions: Exposure to phthalates in daily life during childhood affects liver enzyme levels in adolescence. Elevated liver enzyme levels are associated with the development of metabolic syndrome, implying that attention should be paid to phthalate exposure during childhood., (© 2023. The Author(s).)

Objectives: The aim of this study was to evaluate the subjective level of health-related quality of life of Korean healthcare workers using various quality-of-life instruments., Methods: This study included 992 participants, who were doctors and nurses. A survey was conducted between November 28 and December 4, 2019. Data from 954 participants divided into 3 groups (physicians, residents, and nurses) were analyzed. Four measurement tools (29 questions) were used in the survey to evaluate subjective health status and well-being., Results: In the Mayo Well-being Index, burnout during work (88.5%) and emotional difficulties caused by work (84.0%) were frequently cited by the respondents. Regarding questions on burnout and emotional difficulties, residents and nurses had the highest scores (91.0 and 89.6%, respectively). Emotional problems, such as anxiety, depression, and irritability, accounted for a high percentage (73.1%) of the total, while 82.2% of respondents reported that their work schedules interfered with their leisure and family time. There was no significant difference among the groups in subjective health status. However, 10.1% of the residents experienced very low quality of life, which was a higher proportion than that of physicians (2.7%) and nurses (5.2%)., Conclusions: The level of well-being that Korean medical workers experienced in relation to work was lower than the results of the United States healthcare workers surveyed using the same tool. This study was unique in that it conducted a subjective quality-of-life survey on Korean healthcare workers.

The National Hospice and Palliative Care (NHPC) registry is a nationwide database in Korea that systematically collects information on terminally ill cancer patients receiving inpatient hospice care. From 2018 to 2020, a total of 47,911 patients were enrolled in the NHPC registry from hospitals providing inpatient hospice care. The NHPC database mainly contains the socio-demographic and clinical information of the registered patients. Among these patients, approximately 75% were 60 years or older, and the ratio of males to females was 1:1.41. Lung, liver, colorectal, pancreatic, and gastric cancer made up nearly 90% of the cancer sites among the registered patients. Upon their initial admission to the hospice ward, around 80% of the patients were aware of their terminal illness. About half of the patients had mild pain at the time of the initial admission to the hospice ward, and the duration of hospice care was 14 days (interquartile range, 6-30) in 2019 and 2020. The NHPC registry aims to provide national statistics on inpatient hospice care to assist health policy-making.

Reported here are substrate-dictated rearrangements of chrysanthenol derivatives prepared from verbenone to access complex bicyclic frameworks. These rearrangements set the stage for a 10-step formal synthesis of the natural product xishacorene B. Key steps include an anionic allenol oxy-Cope rearrangement and a Suárez directed C-H functionalization. The success of this work was guided by extensive computational calculations which provided invaluable insight into the reactivity of the chrysanthenol-derived systems, especially in the key oxy-Cope rearrangement.

Methods that functionalize the periphery of azacylic scaffolds have garnered increasing interest in recent years. Herein, we investigate the selectivity of a solid-state Norrish-Yang cyclization (NYC) and subsequent C-C cleavage/cross-coupling reaction of a strained cyclopropane-fused azacyclic system. Surprisingly, the NYC primarily furnished a single lactam constitutional and diastereo-isomer. The regioselectivity of the C-C cleavage of the α-hydroxy-β-lactam moiety could be varied by altering the ligand set used in the coupling chemistry. Experimental and computational observations are discussed.

Purpose: This study aimed to explore turnover rates for Korean acute care hospital nurses and identify factors influencing their turnover., Methods: The study was retrospective in nature. Nurse cohort data were obtained from hospital status data from Korea's Health Insurance Review Assessment Service. The observation period was from January 1, 2012 to December 31, 2016, and data for 96,158 nurses were analyzed. Independent variables included nurses' age and sex and hospital setting, type, ownership, and nurse staffing level. Kaplan-Meier analysis was performed to estimate survival curves, and factors influencing turnover were analyzed using Cox's proportional hazard regression., Results: The cumulative turnover probability for all nurses was .17, .29, .38, .45, and .50 for the first, second, third, fourth, and fifth years, respectively. The results showed that the longer the career duration, the lower the turnover rates. According to the factors influencing nurse turnover, both nurses' (i.e., sex and career duration) and hospitals' (i.e., hospital setting, type, ownership, and nurse staffing level) characteristics were statistically significant., Conclusion: It should be noted that the turnover rate of nurses with less than three year of career duration and of those with less than one year has been shown to be quite high. Therefore, target populations for acute care hospital nurse turnover should be expanded from new graduate nurses to experienced nurses with less than 3 years of career. Further studies are required to examine the causes of high turnover rates in hospitals that are small and/or have low nurse staffing levels., Competing Interests: Conflicts of interest The authors have declared that no competing interests exist., (Copyright © 2020. Published by Elsevier B.V.)

Herein we report the synthesis of substituted indolizidines and related N-fused bicycles from simple saturated cyclic amines through sequential C-H and C-C bond functionalizations. Inspired by the Norrish-Yang Type II reaction, C-H functionalization of azacycles is achieved by forming α-hydroxy-β-lactams from precursor α-ketoamide derivatives under mild, visible light conditions. Selective cleavage of the distal C(sp 2 )-C(sp 3 ) bond in α-hydroxy-β-lactams using a Rh-complex leads to α-acyl intermediates which undergo sequential Rh-catalyzed decarbonylation, 1,4-addition to an electrophile, and aldol cyclization, to afford N-fused bicycles including indolizidines. Computational studies provide mechanistic insight into the observed positional selectivity of C-C cleavage, which depends strongly on the groups bound to Rh trans to the phosphine ligand.

Metal-free, visible-light-induced site-selective heteroarylation of remote C(sp 3 )-H bonds has been accomplished through the design of N-alkoxyheteroarenium salts serving as both alkoxy radical precursors and heteroaryl sources. The transient alkoxy radical can be generated by the single-electron reduction of an N-alkoxypyridinium substrate by a photoexcited quinolinone catalyst. Subsequent radical translocation of the alkoxy radical forms a nucleophilic alkyl radical intermediate, which undergoes addition to the substrate to achieve remote C(sp 3 )-H heteroarylation. This cascade strategy provides a powerful platform for remote C(sp 3 )-H heteroarylation in a controllable and selective manner and is well suited for late-stage functionalization of complex bioactive molecules., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Recent studies suggest that uric acid plays a causal role in the development of hypertension in relation to birth weight. The aim of the study was to elucidate the effect of prenatal and/or postnatal growth status on serum uric acid levels in children at 3 years of age., Methods: A total of 178 children from the birth cohort at Ewha Womans University Hospital were followed. Anthropometric characteristics, blood pressure, and serum uric acid were measured at 3 years of age., Results: The level of serum uric acid was significantly higher in hypertensive children (3.8 mg/dl) than in nonhypertensive children (3.4 mg/dl). Preterm birth and lower placental weight were the preterm factors significantly associated with increased serum uric acid in early childhood. In addition, current weight, body mass index, and change-in-weight s.d. score from birth to current were also associated with serum uric acid level. Both the first- and fourth-quartile groups for weight and weight gain presented higher levels of serum uric acid. We found that the highest uric acid level belonged to the group of preterm or low birth weight (LBW) and higher change in weight s.d. score. Children who were born at full term or with a normal birth weight and lower change in weight s.d. score had the lowest serum uric acid levels., Conclusion: Preterm birth and a subsequent high rate of postnatal weight gain are risk factors for increased serum uric acid levels in early childhood.