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Organic light-emitting diodes (OLEDs) exhibiting thermally activated delayed fluorescence (TADF) demonstrate high quantum efficiencies. However, their drawbacks include a short device lifetime and low efficiencies in the high-luminance region. This study synthesizes a blue TADF emitter by modifying robust, stable 5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene (DOBNA). By introducing a benzonitrile group into DOBNA as an acceptor with extended π-conjugation and using a carbazole donor, a donor–acceptor–donor structure (DOB-1) is formed. To increase the lifetime and efficiency, carbazole derivative donors substituted with tert-butyl (DOB-2) or phenyl (DOB-3) are introduced at both the 3 and 6 positions to enhance the electron-donating characteristics, achieving a high photoluminescence quantum yield (PLQY), a superior horizontal transition dipole orientation (HTDO) ratio, and fast reverse intersystem crossing (RISC). As-synthesized DOB-2 and DOB-3 exhibit higher PLQYs (0.92 and 0.95) than DOB-1 (0.83), along with fast RISC (∼105 s−1) and better HTDO ratios (0.86 and 0.90) than DOB-1 (0.74). The TADF OLEDs employing DOB-2 and DOB-3 demonstrate 1.69 and 2.05 times higher external quantum efficiencies, respectively. Notably, the DOB-2 and DOB-3-based OLEDs exhibit operational lifetimes (LT50 at 2000 cd m−2) of 706 and 1377 h, which are 2.52 and 4.54 times longer than that of DOB-1 emitters. Our results will advance research on efficient, long-lifetime TADF materials for OLEDs. [ABSTRACT FROM AUTHOR]

Enhancing corporate accountability in areas such as environment, social, and governance (ESG) has solidified its role in the discussion on improving corporate resilience and growth. ESG management activities not only augment corporate sustainability and risk control but also influence the professional roles and personal lives of members through their perceived ESG. Historically, most ESG research has centered on the interrelation of corporate ESG endeavors and outcomes, while studies focusing on the influence of perceived ESG on members have been sparse. In this light, our investigation, rooted in the conservation of resources theory, aimed to delineate the mechanistic link between perceived ESG and members' psychological well-being. This study employed a stratified random sampling technique and collected data across three waves, each spaced four weeks apart. Our sample comprised 325 Korean employees working in administrative, technical, service, and sales roles. This study recruited 325 Korean employees across three time-lagged phases and found that ESG comprehension enhances job meaningfulness, subsequently amplifying psychological wellness. Intriguingly, as pay satisfaction escalates, the mediating role of job meaningfulness between perceived ESG and well-being intensifies. Our study underscores that for organizations to harness perceived ESG to boost psychological well-being via job meaningfulness, managing pay satisfaction is imperative. These findings highlight a crucial policy implication: policymakers must actively promote ESG awareness and incorporate it into employee compensation strategies. This integration is essential to cultivating a healthier, more engaged workforce and driving long-term organizational success. [ABSTRACT FROM AUTHOR]

Background: Subjective cognitive decline (SCD) refers to the self-reported persistent cognitive decline despite normal objective testing, increasing the risk of dementia compared to cognitively normal individuals. Objective: This study aims to investigate the attributes of SCD patients who demonstrated memory function improvement. Methods: In this prospective study of SCD, a total of 120 subjects were enrolled as part of a multicenter cohort study aimed at identifying predictors for the clinical progression to mild cognitive impairment or dementia (CoSCo study). All subjects underwent 18F-florbetaben PET and brain MRI scans at baseline and annual neuropsychological tests. At the 24-month follow-up, we classified SCD patients based on changes in memory function, the z-score of the Seoul verbal learning test delayed recall. Results: Of the 120 enrolled patients, 107 successfully completed the 24-month follow-up assessment. Among these, 80 patients (74.8%) with SCD exhibited memory function improvements. SCD patients with improved memory function had a lower prevalence of coronary artery disease at baseline and performed better in the trail-making test part B compared to those without improvement. Anatomical and biomarker analysis showed a lower frequency of amyloid PET positivity and larger volumes in the left and right superior parietal lobes in subjects with improved memory function. Conclusions: Our prospective study indicates that SCD patients experiencing memory improvement over a 24-month period had a lower amyloid burden, fewer cardiovascular risk factors, and superior executive cognitive function. Identifying these key factors associated with cognitive improvement may assist clinicians in predicting future memory function improvements in SCD patients. [ABSTRACT FROM AUTHOR]