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• Four TADF materials with carbazole donor, and benzonitrile-substituted pyrimidine or triazine as acceptor core were developed. • OLEDs with m-CzPym, p-CzPym, m-CzTrz, and p-CzTrz as host and 4CzIPN were fabricated. • An impressive external quantum efficiency of 31.5% and a superior power efficiency of 116.5 lm W−1 were achieved. • Impressive efficiency roll-off performance (approximately 90% of EQE max at 5000 cd m−2). Four bipolar molecules, namely m-CzPym , p-CzPym , m-CzTrz , and p-CzTrz , with carbazole (Cz) donor and a benzonitrile-substituted pyrimidine (Pym) or triazine (Trz) acceptor core were synthesized and characterized. The electron deficiency of heteroaryl cores together with the substitution pattern of benzonitrile were employed to tune the energy levels as well as the thermally activated delayed fluorescence (TADF) characteristics. The four molecules exhibited TADF behavior with inferior photoluminescent quantum yields (PLQYs) that limit their applications as emitters. These bipolar molecules were employed as TADF host materials for the benchmark TADF emitter 4CzIPN to achieve high-performing green TADF organic light-emitting diodes (OLEDs). Among the molecules, m-CzPym -hosted TADF-OLEDs achieved a maximum external quantum efficiency (EQE max) of 31.5%, maximum power efficiency (PE max) of 95.6 lm/W, and maximum current efficiency (CE max) of 100.2 cd/A. Notably, p-CzPym -hosted TADF-OLEDs also achieved a PE max of 116.5 lm/W, turn-on voltage of 2.5 V, and impressive low efficiency roll-off performance (>89% of EQE max at 5000 cd/m2), representing one of the highest efficiencies ever reported in 4CzIPN-doped devices. The high device efficiency can be ascribed to the balanced ambipolar carrier-transporting character of the host materials and high PLQY as well as the outstanding light outcoupling efficiency of the emitting layer. [ABSTRACT FROM AUTHOR]

Background: The Internet is an increasingly important source of health information for the general population. Both preventive health behavior and Internet use are known to be different between men and women. However, few studies have compared predictors of Internet use for health information between the sexes.Objectives: To investigate the prevalence and predictors of Internet use for health information among male and female adult Internet users using data from a population-based survey in Taiwan.Methods: Respondents between the ages of 20-65 years were identified from the dataset of the 2009 Taiwan National Health Interview Survey. The outcome variable of the study, the utilization of the Internet for health information, was ascertained by asking whether the respondent had ever used the Internet to search for health information or obtain health services. Univariate and multivariate logistic regression analyses were conducted separately for men and women to evaluate factors associated with the use of Internet for health information.Results: Of the 2741 adults aged 20-65 years who had ever used the Internet, 1766 (64.4%) of them had used it for health information or services. Multivariate logistic regression analyses showed that a higher educational level (adjusted odds ratio [AOR]=3.60, P<0.001), living alone (AOR=1.77, P=0.019), had exercised in the past two weeks (AOR=2.41, P<0.001), residing in city or urban district (AOR=1.28, P=0.049), with a perceived health status of extremely good, very good, or good (AOR=1.34, P=0.022), and had used Western medicine services in the past month (AOR=1.51, P=0.005) were significantly associated with health information use in male Internet users. On the other hand, age between 20-44.9 years (AOR=1.87, P<0.001), a higher educational level (AOR=3.57, P<0.001), being married (AOR=1.68, P=0.001), had exercised in the past two weeks (AOR=1.56, P<0.001), and had a mean monthly personal income of NT$ 20,000 and above were significant factors in female Internet users.Conclusions: This secondary data analysis of a representative sample of Taiwan population revealed that a similar but not identical set of independent factors was associated with the use of Internet for health information between male and female Internet users. [ABSTRACT FROM AUTHOR]