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Hydroamination of alkenes, the addition of the N-H bond of an amine across an alkene, is a fundamental, yet challenging, organic transformation that creates an alkylamine from two abundant chemical feedstocks, alkenes and amines, with full atom economy1-3. The reaction is particularly important because amines, especially chiral amines, are prevalent substructures in a wide range of natural products and drugs. Although extensive efforts have been dedicated to developing catalysts for hydroamination, the vast majority of alkenes that undergo intermolecular hydroamination have been limited to conjugated, strained, or terminal alkenes2-4; only a few examples occur by the direct addition of the N-H bond of amines across unactivated internal alkenes5-7, including photocatalytic hydroamination8,9, and no asymmetric intermolecular additions to such alkenes are known. In fact, current examples of direct, enantioselective intermolecular hydroamination of any type of unactivated alkene lacking a directing group occur with only moderate enantioselectivity10-13. Here we report a cationic iridium system that catalyses intermolecular hydroamination of a range of unactivated, internal alkenes, including those in both acyclic and cyclic alkenes, to afford chiral amines with high enantioselectivity. The catalyst contains a phosphine ligand bearing trimethylsilyl-substituted aryl groups and a triflimide counteranion, and the reaction design includes 2-amino-6-methylpyridine as the amine to enhance the rates of multiple steps within the catalytic cycle while serving as an ammonia surrogate. These design principles point the way to the addition of N-H bonds of other reagents, as well as O-H and C-H bonds, across unactivated internal alkenes to streamline the synthesis of functional molecules from basic feedstocks.In late 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first detected in China and has since caused a pandemic of coronavirus disease 2019 (COVID-19). The first case of COVID-19 in New York City was officially confirmed on 1 March 2020 followed by a severe local epidemic1. Here, to understand seroprevalence dynamics, we conduct a retrospective, repeated cross-sectional analysis of anti-SARS-CoV-2 spike antibodies in weekly intervals from the beginning of February to July 2020 using more than 10,000 plasma samples from patients at Mount Sinai Hospital in New York City. We describe the dynamics of seroprevalence in an 'urgent care' group, which is enriched in cases of COVID-19 during the epidemic, and a 'routine care' group, which more closely represents the general population. Seroprevalence increased at different rates in both groups; seropositive samples were found as early as mid-February, and levelled out at slightly above 20% in both groups after the epidemic wave subsided by the end of May. From May to July, seroprevalence remained stable, suggesting lasting antibody levels in the population. Our data suggest that SARS-CoV-2 was introduced in New York City earlier than previously documented and describe the dynamics of seroconversion over the full course of the first wave of the pandemic in a major metropolitan area.

This study aimed to identify the relationship between workplace violence and turnover intention, and the mediation effect of resilience on the relationship in hospital nurses.

This was a cross-sectional study. A total of 237 registered nurses were recruited from three hospitals in South Korea from April to May 2019. Participants were invited to complete self-reported questionnaires that measure workplace violence, turnover intention, resilience, and demographic information. The data obtained were analyzed using multiple regression and a simple mediation model applying the PROCESS macro with 95% bias-corrected bootstrap confidence interval (5,000 bootstrap resampling).

After controlling demographic covariates, workplace violence significantly accounted for the variance of turnover intention. It was also demonstrated that resilience partially mediated the relationship between workplace violence and turnover intention in hospital nurses. Selleck Gefitinib A 73.8% of nurses had experienced workplace violence (such as attack on personality, attack on professional status, isolation from work, or direct attack).

Workplace violence directly influences turnover intention of nurses and indirectly influences it through resilience. Therefore, hospital administrators need to develop and provide a workplace violence preventive program and resilience enhancement program to decrease nurses' turnover intention, and leaving.

Workplace violence directly influences turnover intention of nurses and indirectly influences it through resilience. Therefore, hospital administrators need to develop and provide a workplace violence preventive program and resilience enhancement program to decrease nurses' turnover intention, and leaving.

The aim of this study was to develop a situation-specific theory to explain the disease management experience of patients with asthma.

Twenty participants with asthma were selected using the theoretical sampling method. The data were acquired through in-depth interviews conducted from June to October 2018 and analyzed using the grounded theory approach of Strauss and Corbin.

In total, 69 concepts, 30 subcategories, and 13 categories were generated to explain the disease management experience of patients with asthma. The core category of the disease management experience of patients with asthma was 'management of the disease to prevent aggravation of symptoms over the lifetime'. The disease management process of asthma patients included three steps the 'cognition phase', the 'adjustment phase', and the 'maintenance phase'. However, some patients remained in the 'stagnation phase' of disease management, which represents the result of the continual pursuit of risky health behavior. There were three types of disease management experiences among patients with asthma 'self-managing', 'partially self-managing', and 'avoidant'.

This study shows that patients with asthma must lead their disease management process to prevent exacerbation of their symptoms. It is imperative to develop nursing strategies and establish policies for effective disease management of patients with asthma based on their individual disease management processes and types.

This study shows that patients with asthma must lead their disease management process to prevent exacerbation of their symptoms. It is imperative to develop nursing strategies and establish policies for effective disease management of patients with asthma based on their individual disease management processes and types.

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