A barely reached balance between weak intramolecular‐charge‐transfer (ICT) and small singlet–triplet splitting energy (ΔEST) for reverse intersystem crossing from non‐emissive triplet state to ...radiative singlet state impedes the realization of deep‐blue thermally activated delayed fluorescence (TADF) materials. By discarding the twisted‐ICT framework for a flattened molecular backbone and introducing a strong acceptor possessing n–π* transition character, hypsochromic color, a large radiative rate (kF), and small ΔEST are achieved simultaneously. Six molecules with a 9,9‐dimethyl‐10‐phenyl‐9,10‐dihydroacridine (i‐DMAc) donor are synthesized and investigated. Coinciding with time‐dependent density functional theory, the reduced dihedral angles between donor (D) and acceptor (A) weaken ICT from dispersed charge density and enable a large kF from increased frontier molecular orbitals overlap. Despite the separated highest occupied (HOMO) and lowest unoccupied molecular orbital (LUMO) population, the intercalation of phenyl bridges between D–A increases kF but significantly lowers the local triplet excited state, indicating small HOMO and LUMO overlap is not a sufficient, but necessary condition for reduced ΔEST. Integrating short conjugation length and carbonyl or triazine acceptors into the complanation molecules, deep‐blue TADF organic light‐emitting diodes demonstrate maximum external quantum efficiencies of 11.5% and 10.9% with Commission Internationale de l'Eclairage coordinates of (0.16, 0.09) and (0.15, 0.11), respectively, which is quite close to the stringent National Television System Committee blue standard.
Integrating a strong electron‐withdrawing acceptor moiety with short conjugation length and n–π* character into a planar molecular backbone is promising for meeting high radiative rate, weak intramolecular charge‐transfer state, and small singlet–triplet splitting energy simultaneously. Employing such a strategy, deep‐blue organic light emitting diode with external quantum efficiency of 11.5% and Commission Internationale de l'Eclairage coordinates of (0.16, 0.09) is achieved.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Luminescent materials with thermally activated delayed fluorescence (TADF) can harvest singlet and triplet excitons to afford high electroluminescence (EL) efficiencies for organic light‐emitting ...diodes (OLEDs). However, TADF emitters generally have to be dispersed into host matrices to suppress emission quenching and/or exciton annihilation, and most doped OLEDs of TADF emitters encounter a thorny problem of swift efficiency roll‐off as luminance increases. To address this issue, in this study, a new tailor‐made luminogen (dibenzothiophene‐benzoyl‐9,9‐dimethyl‐9,10‐dihydroacridine, DBT‐BZ‐DMAC) with an unsymmetrical structure is synthesized and investigated by crystallography, theoretical calculation, spectroscopies, etc. It shows aggregation‐induced emission, prominent TADF, and interesting mechanoluminescence property. Doped OLEDs of DBT‐BZ‐DMAC show high peak current and external quantum efficiencies of up to 51.7 cd A−1 and 17.9%, respectively, but the efficiency roll‐off is large at high luminance. High‐performance nondoped OLED is also achieved with neat film of DBT‐BZ‐DMAC, providing excellent maxima EL efficiencies of 43.3 cd A−1 and 14.2%, negligible current efficiency roll‐off of 0.46%, and external quantum efficiency roll‐off approaching null from peak values to those at 1000 cd m−2. To the best of the authors' knowledge, this is one of the most efficient nondoped TADF OLEDs with small efficiency roll‐off reported so far.
A highly efficient nondoped organic light‐emitting diode affording excellent maxima electroluminescence efficiencies of 43.3 cd A−1 and 14.2%, negligible current efficiency roll‐off of 0.46%, and external quantum efficiency roll‐off approaching null from peak values to those at 1000 cd m−2, is attained based on a robust luminogen featuring aggregation‐induced emission and thermally activated delayed fluorescence.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Recently, a new route to achieve 100% internal quantum efficiency white organic light‐emitting diodes (WOLEDs) is proposed by utilizing noble‐metal‐free thermally activated delayed fluorescence ...(TADF) emitters due to the radiative contributions of triplet excitons by effective reverse intersystem crossing. However, a systematic understanding of their reliability and internal degradation mechanisms is still deficient. Here, it demonstrates high performance and operational stable purely organic fluorescent WOLEDs consisting of a TADF assistant host via a strategic exciton management by multi‐interlayers. By introducing such interlayers, carrier recombination zone could be controlled to suppress the generally unavoidable quenching of long‐range triplet excitons, successfully achieving remarkable external quantum efficiency of 15.1%, maximum power efficiency of 48.9 lm W−1, and extended LT50 lifetime (time to 50% of initial luminance of 1000 cd m−2) exceeding 2000 h. To this knowledge, this is the first pioneering work for realizing high efficiency, low efficiency roll‐off, and operational stable WOLEDs based on a TADF assistant host. The current findings also indicate that broadening the carrier recombination region in both interlayers and yellow emitting layer as well as restraining exciplex quenching at carrier blocking interface make significant roles on reduced efficiency roll‐off and enhanced operational lifetime.
A feasible concept of exciton‐adjustable interlayers Bepp2:mCBP/Bepp2 is proposed to realize application prospect of high efficiency, low efficiency roll‐off, and long lifetime pure organic white organic light‐emitting diodes by using a thermally activated delayed fluorescence assistant host.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Resting-state fMRI (RS-fMRI) has been drawing more and more attention in recent years. However, a publicly available, systematically integrated and easy-to-use tool for RS-fMRI data processing is ...still lacking. We developed a toolkit for the analysis of RS-fMRI data, namely the RESting-state fMRI data analysis Toolkit (REST). REST was developed in MATLAB with graphical user interface (GUI). After data preprocessing with SPM or AFNI, a few analytic methods can be performed in REST, including functional connectivity analysis based on linear correlation, regional homogeneity, amplitude of low frequency fluctuation (ALFF), and fractional ALFF. A few additional functions were implemented in REST, including a DICOM sorter, linear trend removal, bandpass filtering, time course extraction, regression of covariates, image calculator, statistical analysis, and slice viewer (for result visualization, multiple comparison correction, etc.). REST is an open-source package and is freely available at http://www.restfmri.net.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Two thioxanthone‐derived isomeric series of thermally activated delayed fluorescence (TADF) emitters 1,6‐2TPA‐TX/3,6‐2TPA‐TX and 1,6‐2TPA‐TXO/3,6‐2TPA‐TXO are developed for organic light‐emitting ...diodes (OLEDs). Blue emission devices based on symmetrical 3,6‐2TPA‐TX with common vertical transition route realize an extremely high external quantum efficiency (EQE) of 23.7%, and an ever highest EQE of 24.3% is achieved for yellow emission devices based on 3,6‐2TPA‐TXO by solely changing the sulfur atom valence state of the thioxanthone core. In contrast, their corresponding asymmetric isomers are affected by intramolecular energy transfer and more severely by a nonradiative deactivation pathway, to give much low EQE values (<5%). By utilizing 3,6‐2TPA‐TX as a blue emitter and 3,6‐2TPA‐TXO as a yellow emitter, an ever highest EQE of 20.4% is achieved for all‐fluorescence white OLEDs.
Two thioxanthone‐derived isomeric series of thermally activated delayed fluorescence emitters with the same electron acceptor and electron donor but different donor combining strategy are developed. Highly efficient sky‐blue, yellow, and white organic light‐emitting diodes are achieved by 3,6‐2TPA‐TX and 3,6‐2TPA‐TXO with symmetrical configuration and common vertical transition route.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
We investigated serum soluble CD163 (sCD163) levels for use in the diagnosis, severity assessment, and prognosis of sepsis in the critical ill patients and compared sCD163 with other ...infection-related variables.
During july 2010 and April 2011, serum was obtained from 102 sepsis patients (days 1, 3, 5, 7, and 10 after admission to an ICU) and 30 systemic inflammatory response syndrome (SIRS) patients with no sepsis diagnosed. Serum levels of sCD163, procalcitonon (PCT), and C reactive protein (CRP) were determined respectively. Sequential organ failure assessment (SOFA) scores for sepsis patients were also recorded. Then evaluated their roles in sepsis.
The sCD163 levels were 0.88(0.78-1.00) ug/mL for SIRS patients, 1.50(0.92-2.00) ug/mL for moderate sepsis patients, and 2.95(2.18-5.57) ug/mL for severe sepsis patients on day 1. The areas under the ROC curves for sCD163, CRP, and PCT for the diagnosis of sepsis were, respectively, 0.856(95%CI: 0.791-0.921), 0.696(95%CI: 0.595-0.797), and 0.629(95%CI: 0.495-0.763), At the recommended cut-off 1.49 ug/mL for sCD163, the sensitivity is 74.0% with 93.3% specificity. Based on 28-day survivals, sCD163 levels in the surviving group stay constant, while they tended to gradually increase in the non-surviving group.The area under the ROC curve for sCD163 for sepsis prognosis was 0.706(95%CI 0.558-0.804). Levels of sCD163 with cut-off point >2.84 ug/mL have sensitivity of 55.8.0%, specificity 80.4%. Common risk factors for death and sCD163 were included in multivariate logistic regression analysis; the odds ratios (OR) for sCD163 and SOFA scores for sepsis prognosis were 1.173 and 1.396, respectively (P<0.05). Spearman rank correlation analysis showed that sCD163 was weakly, but positively correlated with CRP, PCT, and SOFA scores (0.2< r <0.4, P<0.0001), but not with leukocyte counts (r <0.2, P = 0.450).
Serum sCD163 is superior to PCT and CRP for the diagnosis of sepsis and differentiate the severity of sepsis. sCD163 levels were more sensitive for dynamic evaluations of sepsis prognosis. Serum sCD163 and SOFA scores are prognostic factors for sepsis.
www.chictr.orgChiCTR-ONC-10000812.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Two novel naphtho1,2‐dimidazole derivatives are developed as deep‐blue, light‐emitting materials for organic light‐emitting diodes (OLEDs). The 1H‐naphtho1,2‐dimidazole based compounds exhibit a ...significantly superior performance than the 3H‐naphtho1,2‐dimidazole analogues in the single‐layer devices. This is because they have a much higher capacity for direct electron‐injection from the cathode compared to their isomeric counterparts resulting in a ground‐breaking EQE (external quantum efficiency) of 4.37% and a low turn‐on voltage of 2.7 V, and this is hitherto the best performance for a non‐doped single‐layer fluorescent OLED. Multi‐layer devices consisting of both hole‐ and electron‐transporting layers, result in identically excellent performances with EQE values of 4.12–6.08% and deep‐blue light emission (Commission Internationale de l'Eclairage (CIE) y values of 0.077–0.115) is obtained for both isomers due to the improved carrier injection and confinement within the emissive layer. In addition, they showed a significantly better blue‐color purity than analogous molecules based on benzimidazole or phenanthro9,10‐dimidazole segments.
Novel naphtho1,2‐dimidazole derivatives are developed as light‐emitting materials for OLEDs. 1H‐naphtho1,2‐dimidazole based compounds exhibit a significantly superior performance than their isomeric counterparts in the single‐layer devices owing to the much higher electron injection ability directly from the cathode. However, in the multi‐layer devices, uniformly high efficiencies are obtained with a desirable bluecolor that is more pure than that of their benzimidazole and phenanthro9,10‐dimidazole analogues.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A chromaticity‐adjustable yellow thermally activated delayed fluorescence (TADF) material, PXZDSO2 as a triplet harvester provides a rational device concept, giving two‐color and three‐color pure ...organic white organic light‐emitting diodes (WOLEDs) with unprecedented color‐rendering index of 95 and external quantum efficiency of 19.2%.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Aggregation-induced emission (AIE) materials have excellent solid-state emission by suppressing concentration quenching and exciton annihilation, while thermally activated delayed fluorescence (TADF) ...materials are able to fully utilize electrogenerated singlet and triplet excitons. The collaboration of AIE and TADF should be a rational strategy to design novel robust luminescent materials. Herein, two new materials with both prominent AIE and TADF properties are developed based on a central benzoyl acceptor core and different donor units. Their crystal and electronic structures, thermal stabilities, photophysical properties, and energy levels are investigated systematically. The doped organic light-emitting diodes (OLEDs) based on them show green lights and perform outstandingly, providing excellent electroluminescence (EL) efficiencies of up to 19.2%, 60.6 cd A–1, and 59.2 lm W–1. Their nondoped OLEDs are turned on at very low turn-on voltages (2.7 V) and afford yellow lights and high EL efficiencies of 9.7%, 26.5 cd A–1, and 29.1 lm W–1, with low efficiency roll-off. These results actually demonstrate the feasibility to explore new efficient emitters by the marriage of AIE and TADF.
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IJS, KILJ, NUK, PNG, UL, UM
This meta‐analysis was performed to determine the accuracy of procalcitonin (PCT) in predicting mortality in pneumonia patients with different pathogenic features and disease severities. A systematic ...search of English‐language articles was performed using PubMed, Embase, Web of Knowledge and the Cochrane Library to identify studies. The diagnostic value of PCT in predicting prognosis was determined using a bivariate meta‐analysis model. The Q‐test and I2 index were used to test heterogeneity. A total of 21 studies comprising 6007 patients were included. An elevated PCT level was a risk factor for death from community‐acquired pneumonia (CAP) (risk ratio (RR) 4.38, 95% confidence interval (CI) 2.98–6.43), particularly in patients with a low CURB‐65 score. The commonly used cut‐off, 0.5 ng/mL, had low sensitivity (SEN) and was not able to identify patients at high risk of dying. Furthermore, the PCT assay with functional SEN <0.1 ng/mL was necessary to predict mortality in CAP in the clinic. For critically ill patients, an elevated PCT level was associated with an increased risk of mortality (RR 4.18, 95% CI: 3.19–5.48). The prognostic performance was nearly equal between patients with ventilator‐associated pneumonia (VAP) and patients with CAP.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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