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Perovskite solar cells (pero-SCs) are highly unstable even under trace water. Although the blanket encapsulation (BE) strategy applied in the industry can effectively block moisture invasion, the commercial UV-curable adhesives (UVCAs) for BE still trigger power conversion efficiency deterioration, and the degradation mechanism remains unknown. For the first time, the functions of commercial UVCAs are revealed in BE-processed pero-SCs, where the small-sized monomer easily permeates to the perovskite surface, forming an insulating barrier to block charge extraction, while the high-polarity moiety can destroy perovskite lattice. To solve these problems, a macromer, named PIBA is carefully designed, by grafting two acrylate terminal groups on the highly gastight polyisobutylene and realizes an increased molecular diameter as well as avoided high-polarity groups. The PIBA macromer can stabilize on pero-SCs and then sufficiently crosslink, forming a compact and stable network under UV light without sacrificing device performance during the BE process. The resultant BE devices show negligible efficiency loss after storage at 85% relative humidity for 2000 h. More importantly, these devices can even reach ISO 20653:2013 Degrees of protection IPX7 standard when immersed in one-meter-deep water. This BE strategy shows good universality in enhancing the moisture stability of pero-SCs, irrespective of the perovskite composition or device structure.
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Objective: This study aimed to evaluate the predictive value of neutrophil to lymphocyte ratio (NLR) for poor outcomes within 90-day in hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods: A retrospective study including 503 AECOPD patients was performed, and the subjects' clinical characteristics were collected. Binary logistic regression analysis was used to identify risk factors for 90-day poor outcomes in patients with AECOPD. Receiver-operating characteristic curves (ROC) and areas under the curves (AUC) were used to assess the ability of different biomarkers to predict the risk of 90-day mortality, readmission and re-exacerbation in patients with AECOPD. Results: During the follow-up, 188 patients (38.4%) redeveloped exacerbations, 112 patients (22.9%) were readmitted, and 20 patients (4.1%) died directly resulted from COPD or COPD-related causes. Multivariate analysis demonstrated that age>72 years (OR: 14.817, 95% CI: 1.561-140.647), NLR>14.17 (OR: 9.611, 95% CI: 2.303-40.113), EOS<0.15% (OR: 8.621, 95% CI: 3.465-34.913) and BNP>2840ng/L (OR: 5.291, 95% CI: 1.367-20.474) at discharge were independent risk factors for 90-day mortality in AECOPD patients. NLR was the optimal biomarker for predicting 90-day mortality with an AUC of 0.802 (95% CI: 0.631-0.973). Using 14.17 as the critical value of NLR, the sensitivity was 76.7%, and the specificity was 88.9%. Compared with mortality, NLR had no significant advantage in predicting risk of short-term re-exacerbation (AUC=0.580, 95% CI:0.529-0.632, p=0.001) and readmission (AUC=0.555, 95% CI:0.497-0.614, p=0.045), with AUCs less than 0.6. In contrast, the predictive value of EOS (AUC=0.561, 95% CI:0.502-0.621, p=0.038) was slightly better than NLR in terms of readmission within 90 days. CRP did not serve as a well predictive biomarker for the risk of readmission and re-deterioration (p>0.05). Conclusion: NLR is of great value in predicting the risk of poor outcomes, especially COPD associated mortality, in hospitalized patients with AECOPD within 90 days after discharge.
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Neutrófilos , Doença Pulmonar Obstrutiva Crônica , Humanos , Idoso , Prognóstico , Estudos Retrospectivos , Progressão da Doença , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia , Linfócitos , BiomarcadoresRESUMO
Given the high risk of lung cancer (LC) in patients with combined pulmonary fibrosis and emphysema (CPFE), and the difficulty of early diagnosis, it is important to understand the impact of LC in these patients. The effect of LC on the development of acute exacerbation (AE) as a natural course of CPFE is still unknown. We retrospectively reviewed medical records of patients at the West China Hospital and enrolled 59 patients with CPFE combined with LC and 68 CPFE patients without LC for initial diagnosis matched in the same period. We compared the clinical characteristics and imaging features of CPFE patients with LC and without LC, and analyzed the associated factors for the prevalence of LC using binary logistic regression. Cox proportional hazards regression analysis was performed to explore risk factors of AE as a natural course of CPFE. Patients with CPFE combined with LC were more common among elderly male smokers. The most common pathological type of tumor was adenocarcinoma (24/59, 40.7%) and squamous cell carcinoma (18/59, 30.5%). Compared with those in the without LC group, the proportions of men, and ex- or current smokers, and the levels of smoking pack-years, serum CRP, IL-6, fibrinogen, complement C3 and C4 in patients with LC were significantly higher (p < 0.05). There was no significant difference in the proportion of natural-course-related AE (10.2% vs. 16.2%, p > 0.05) between the two groups. Logistic regression analysis demonstrated that pack-years ≥ 20 (OR: 3.672, 95% CI: 1.165-11.579), family history of cancer (OR: 8.353, 95% CI: 2.368-10.417), the level of fibrinogen > 4.81 g/L (OR: 3.628, 95% CI: 1.403-9.385) and serum C3 > 1.00 g/L (OR: 5.299, 95% CI: 1.727-16.263) were independently associated with LC in patients with CPFE. Compared to those without AE, CPFE patients with AE had significantly higher levels of PLR and serum CRP, with obviously lower DLCO and VC. The obviously increased PLR (HR: 3.731, 95% CI: 1.288-10.813), and decreased DLCO%pred (HR: 0.919, 95% CI: 0.863-0.979) and VC%pred (HR: 0.577, 95% CI: 0.137-0.918) rather than the presence of LC independently contributed to the development of natural-course-related AE in patients with CPFE. Pack-years, family history of cancer, the levels of fibrinogen and serum C3 were independently associated with LC in patients with CPFE. The presence of LC did not significantly increase the risk of AE as a natural course of CPFE. Clinicians should give high priority to CPFE patients, especially those with more severe fibrosis and systemic inflammation, in order to be alert for the occurrence of AE.
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BACKGROUND: Th aim of this study was to analyze acute exacerbation of chronic obstructive pulmonary disease (AECOPD) readmission events and to determine whether neutrophil-to-lymphocyte ratio (NLR) and bilirubin levels were associated with readmission after discharge due to AECOPD. METHODS: A total of 170 patients with AECOPD were included. Patients were stratified into the readmission group if patients had two or more readmissions within 2 years of the previous discharge, and the non-readmission group with one readmission or none within 2 years of the last discharge. Data were collected and compared between groups. The patients were separated by the cutoffs of NLR and bilirubin level. The number of all-cause readmissions within 2 years, time to first COPD-related readmission, 1-year/2-year COPD-related readmission, 1-year/2-year all-cause mortality were compared between groups, respectively. RESULTS: Compared with the readmission group, patients of the non-readmission group had a shorter length of hospital stay, more systemic corticosteroid use, higher NLR, higher bilirubin levels, and lower eosinophils counts (p < 0.05). NLR and bilirubin levels on admission had significant association with the number of all-cause readmissions (p < 0.05). Lower bilirubin was associated with an increased risk of 1-year COPD-related readmission (OR 5.063) and 2-year COPD-related readmission (OR 4.699). CONCLUSIONS: For patients with AECOPD, longer hospital stay, and less use of systemic corticosteroids may be associated with a higher risk of readmission. NLR and bilirubin levels on admission may be related to the number of all-cause readmissions. Bilirubin can be regarded as a biomarker to predict readmission rates within 2 years after discharged throughout the course of the disease.
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Neutrófilos , Doença Pulmonar Obstrutiva Crônica , Humanos , Progressão da Doença , Readmissão do Paciente , Estudos Retrospectivos , LinfócitosRESUMO
Aim: This study aims to clarify the risk factors for falls to prevent severe consequences in older adults. Methods: We searched the PubMed, Web of Science, Embase, and Google Scholar databases using the terms "risk factors" OR "predicting factors" OR "predictor" AND "fall" OR "drop" to identify all relevant studies and compare their results. The study participants were divided into two groups, the "fall group" and the "control group", and differences in demographic characteristics, lifestyles, and comorbidities were compared. Results: We included 34 articles in the analysis and analyzed 22 factors. Older age, lower education level, polypharmacy, malnutrition, living alone, living in an urban area, smoking, and alcohol consumption increased the risk of falls in the aging population. Additionally, comorbidities such as cardiac disease, hypertension, diabetes, stroke, frailty, previous history of falls, depression, Parkinson's disease, and pain increased the risk of falls. Conclusion: Demographic characteristics, comorbidities, and lifestyle factors can influence the risk of falls and should be taken into consideration.
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Acidentes por Quedas , Fragilidade , Hipertensão , Idoso , Humanos , Acidentes por Quedas/prevenção & controle , Envelhecimento , Fragilidade/epidemiologia , Fatores de RiscoRESUMO
Dopant-free organic hole transport materials (HTMs) remain highly desirable for stable and efficient n-i-p perovskite solar cells (pero-SCs) but rarely succeed. Here, we propose a molecular assembly strategy to overcome the limited optoelectronic properties of organic HTMs by precisely designing a linear organic small molecule BDT-DPA-F from the atomic to the molecular levels. BDT-DPA-F can assemble into a fibril network, showing an obviously improved hole mobility and decreased energy disorder. The resultant pero-SCs showed a promising efficiency of 23.12 % (certified 22.48 %), which is the highest certified value of pero-SCs with dopant-free HTMs, to date. These devices also showed a weak-dependence of efficiency on size, enabling a state-of-the-art efficiency of 22.50 % for 1-cm2 device and 20.17 % for 15.64-cm2 module. For the first time, the pero-SCs based on dopant-free HTMs realized ultralong stabilities with T80 lifetimes over 1200â h under operation or thermal aging at 85 °C.
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Nondoped organic light-emitting diodes (OLEDs) have drawn immense attention due to their merits of process simplicity, reduced fabrication cost, etc. To realize high-performance nondoped OLEDs, all electrogenerated excitons should be fully utilized. The thermally activated delayed fluorescence (TADF) mechanism can theoretically realize 100% internal quantum efficiency (IQE) through an effective upconversion process from nonradiative triplet excitons to radiative singlet ones. Nevertheless, exciton quenching, especially related to triplet excitons, is generally very serious in TADF-based nondoped OLEDs, significantly hindering the pace of development. Enormous efforts have been devoted to alleviating the annoying exciton quenching process, and a number of TADF materials for highly efficient nondoped devices have been reported. In this review, we mainly discuss the mechanism, exciton leaking channels, and reported molecular design strategies of TADF emitters for nondoped devices. We further classify their molecular structures depending on the functional A groups and offer an outlook on their future prospects. It is anticipated that this review can entice researchers to recognize the importance of TADF-based nondoped OLEDs and provide a possible guide for their future development.
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The built-in electric field (BEF) intensity of silicon heterojunction solar cells can be easily enhanced by selective doping to obtain high power conversion efficiencies (PCEs), while it is challenging for perovskite solar cells (pero-SCs) because of the difficulty in doping perovskites in a controllable way. Herein, an effective method is reported to enhance the BEF of FA0.92 MA0.08 PbI3 perovskite by doping an organic ferroelectric material, poly(vinylidene fluoride):dabcoHReO4 (PVDF:DH) with high polarizability, that can be driven even by the BEF of the device itself. The polarization of PVDF:DH produces an additional electric field, which is maintained permanently, in a direction consistent with that of the BEF of the pero-SC. The BEF superposition can more sufficiently drive the charge-carrier transport and extraction, thus suppressing the nonradiative recombination occurring in the pero-SCs. Moreover, the PVDF:DH dopant benefits the formation of a mesoporous PbI2 film, via a typical two-step processing method, thereby promoting perovskite growth with high crystallinity and a few defects. The resulting pero-SC shows a promising PCE of 24.23% for a 0.062 cm2 device (certified PCE of 23.45%), and a remarkable PCE of 22.69% for a 1 cm2 device, along with significantly improved moisture resistances and operational stabilities.
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The conformational distribution and mutual interconversion of thermally activated delayed fluorescence (TADF) emitters significantly affect the exciton utilization. However, their influence on the photophysics in amorphous film states is still not known due to the lack of a suitable quantitative analysis method. Herein, we used temperature-dependent time-resolved photoluminescence spectroscopy to quantitatively measure the relative populations of the conformations of a TADF emitter for the first time. We further propose a new concept of "self-doping" for realizing high-efficiency nondoped OLEDs. Interestingly, this "compositionally" pure film actually behaves as a film with a dopant (quasi-equatorial form) in a matrix (quasi-axial form). The concentration-induced quenching that may occur at high concentrations is thus expected to be effectively relieved. The "self-doping" OLED prepared with the newly developed TADF emitter TP2P-PXZ as a neat emitting layer realizes a high maximum external quantum efficiency of 25.4 % and neglectable efficiency roll-off.
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Thermally activated delayed fluorescence (TADF) emitters have aroused considerable attention, particularly for their great potential in organic light-emitting diodes (OLEDs). In typical TADF molecules, intramolecular charge transfer (CT) between electron-donor (D) and electron-acceptor (A) moieties is the dominant transition. Actually, CT transitions can possibly occur between different molecules as well. Herein, we used a nonconjugated triptycene (TPE) moiety to space D and A moieties and developed two novel emitters tBuDMAC-TPE-TRZ and tBuDMAC-TPE-TTR to explore the roles of intra- and intermolecular CT transitions. Along with weak intramolecular CT transitions, intermolecular CT transitions are dominant for tBuDMAC-TPE-TRZ and tBuDMAC-TPE-TTR neat films. Particularly, tBuDMAC-TPE-TRZ showed a high maximum external quantum efficiency of 10.0% in a nondoped solution-processed OLED, which was evidently higher than that of a corresponding 10 wt % tBuDMAC-TPE-TRZ-doped OLED with 4,4',4â³-tris(carbazol-9-yl)triphenylamine (TCTA) as the host matrix. The results prove that intermolecular CT transitions indeed participate in the CT transition process in these systems and they are helpful to enhance the electroluminescence performance of emitting systems with weak intramolecular CT transitions.
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Background: Influenza was an independent risk factor for invasive pulmonary aspergillosis (IPA). In light of increasing incidence and mortality of influenza associated aspergillosis, our study summarized risk factors, clinical characteristics, and prognostic factors of developing aspergillosis in immunocompetent hosts with influenza to further screen high-risk population and improve outcome. Methods: We reviewed the patient characteristics, laboratory examinations, radiological imaging, and microbiology data of 72 influenza patients with IPA and 84 influenza patients without IPA admitted to West China Hospital. Result: Our study shown that aspergillosis co-infection increased overall mortality of severe influenza from 22.6 to 52.8%, along with higher white blood count (WBC) (10.9 ± 5.0 vs. 8.4 ± 3.3, P = 0.016), Neutrophiles (9.5 ± 5.0 vs. 7.0 ± 3.8, P = 0.023), procalcitonin (PCT) (8.6 ± 15.9 vs. 1.2 ± 2.1, P = 0.009), and a lower CD4+ T cell count (189.2 ± 135.3 vs. 367.1 ± 280.0, P = 0.022) in death group. No impact of age, gender, underlying diseases, immunosuppressive agents and steroids use, CD4+ T cell count on incidence of influenza associated aspergillosis was observed. But influenza associated aspergillosis cases mostly accompanied with more H1N1 subtype (91.7 vs. 79.8%, P = 0.037) and higher level of C-reactive protein (CRP) (117.6 ± 88.1 vs. 78.5 ± 75.2, P = 0.017) and interleukin 6 (IL-6) (133.5 ± 149.2 vs. 69.9 ± 100.0, P = 0.021) than those without aspergillosis. Conclusion: Aspergillosis co-infection in severe influenza patients can lead to a significant increased mortality, which was associated with severe respiratory failure due to mixed infection and immunosuppression. Pulmonary excessive inflammatory response was related with IPA co-infection.
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Thermally activated delayed fluorescence (TADF) emitters with aggregation-induced emission (AIE) features are hot candidates for non-doped organic light-emitting diodes (OLEDs), as they are highly emissive in solid states upon photoexcitation. Nevertheless, not every AIE-TADF emitter in the past had guaranteed decent efficiencies in non-doped devices, indicating that the AIE character alone does not necessarily afford ideal non-doped TADF emitters. As intermolecular electron-exchange interaction that involves long-lived triplet excitons plays a dominant role in the whole quenching process of TADF, we anticipate that it is the main reason for the different electroluminescence performances of AIE-TADF emitters. Therefore, in this work, we designed two TADF emitters SPBP-DPAC and SPBP-SPAC by modifying a reported less successful emitter BP-DPAC with extra fluorenes to increase intermolecular distances and attenuate this electron-exchange interaction. With the fluorene lock as steric hindrance, SPBP-DPAC and SPBP-SPAC exhibit significantly higher exciton utilization in non-doped films due to the suppressed concentration quenching. The non-doped OLEDs based on SPBP-DPAC and SPBP-SPAC show an excellent maximum external quantum efficiency (EQE) of 22.8% and 21.3% respectively, and what's even more promising is that ignorable roll-offs at practical brightness (e.g., 1000 and 5000 cd m-2) were realized. These results reveal that locking the phenyl rings as steric hindrance can not only enhance the molecular rigidity, but also cause immediate relief of concentration quenching, and result in significant performance improvement under non-doped conditions. Our approach proposes a feasible molecular modification strategy for AIE-TADF emitters, potentially increasing their applicability in OLEDs.
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Purpose: The current guidelines recommend the use of systemic corticosteroids (SCS) as the optimal treatment for acute exacerbations of chronic obstructive pulmonary disease (AECOPD). The aim of this real-world study was to evaluate whether nebulized budesonide (NBS) could also be used as an initial treatment for AECOPD. Patients and methods: AECOPD patients initially treated with NBS or SCS (oral/intravenous) were enrolled. A large-scale, long-term multicenter cohort study of AECOPD patients was performed to analyze outcomes for each treatment (NCT02051166). Results: Initial NBS and SCS treatment resulted in similar outcomes in terms of improvements in FEV1, PaO2, SaO2, and PaCO2. Disease severity affected outcome similarly in both groups. When the groups were stratified according to whether the initial treatment was subsequently intensified or reduced, more intubation was seen in the groups in which initial treatment was intensified. NBS escalation and SCS reduction groups spent more days in the hospital. The NBS escalation group was associated with the highest medical expenditure and a relatively higher rate of new-onset pneumonia. The NBS maintenance/reduction group showed the lowest mortality rate between groups. Stratification according to initial PaCO2 level showed more intubation in the groups with high initial PaCO2 concentrations. Conclusion: These results indicate that NBS may be used as an initial treatment in certain AECOPD patients, and further studies are needed to better define those most likely to benefit.
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Broncodilatadores/administração & dosagem , Budesonida/administração & dosagem , Glucocorticoides/administração & dosagem , Pulmão/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Idoso , Idoso de 80 Anos ou mais , Broncodilatadores/efeitos adversos , Budesonida/efeitos adversos , China , Progressão da Doença , Feminino , Volume Expiratório Forçado , Glucocorticoides/efeitos adversos , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
Alkaloids are widely present in food and medicine. However, many alkaloids have poisoning effect. Thus, a sensitive and rapid method for determination of alkaloids is highly desired. In this study, a convenient, reliable and accurate method is developed for the simultaneous determination of 16 poisonous alkaloids in human blood by ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) coupled with supported liquid extraction (SLE). The 16 alkaloids include colchicine, anisodamine, scopolamine, atropine, sinomenine, dicaine, thebaine, papaverine, strychnine, brucine, aconitine, hypaconitine, yunaconitine, deoxyaconitine, bullatine A and bullatine B. Low limits of detection (LODs) were obtained ranging in 0.002-0.03⯵gâ¯L-1. The linear ranges are 0.005-200⯵gâ¯L-1 for colchicine, papaverine, brucine, aconitine, hypaconitine, yunaconitine and deoxyaconitine, 0.01-200⯵gâ¯L-1 for anisodamine and scopolamine, 0.05-200⯵gâ¯L-1 for atropine, strychnine, bullatine A and bullatine B, 0. 1-200⯵gâ¯L-1 for other target analytes, all with correlation coefficients (R2) higher than 0.995. The recoveries range from 79.2% to 95.8%. The relative standard deviation (RSD) values are lower than 15% and the values of matrix effect (ME) range in 86.3%-118.2%. This method of UPLC-MS/MS coupled with SLE has high potential for analyzing multiple alkaloids in blood samples.
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Alcaloides/sangue , Cromatografia Líquida de Alta Pressão/métodos , Extração Líquido-Líquido/métodos , Espectrometria de Massas em Tandem/métodos , Alcaloides/química , Alcaloides/isolamento & purificação , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Reprodutibilidade dos TestesRESUMO
Two novel thermally activated delayed fluorescence (TADF) emitters, 3-phenylquinolino[3,2,1- de]acridine-5,9-dione (3-PhQAD) and 7-phenylquinolino[3,2,1- de]acridine-5,9-dione (7-PhQAD), were designed and synthesized based on a rigid quinolino[3,2,1- de]acridine-5,9-dione (QAD) framework. With the effective superimposed resonance effect from electron-deficient carbonyls and electron-rich nitrogen atom, both emitters realize significant TADF characteristics with small Δ ESTs of 0.18 and 0.19 eV, respectively. And, molecular relaxations were dramatically suppressed for both emitters because of their conjugated structure. In the devices, 3-PhQAD realizes superior performance with a maximum external quantum efficiency (EQE) of 19.1% and a narrow full width at half-maximum (FWHM) of 44 nm, whereas a maximum EQE of 18.7% and an extremely narrow FWHM of 34 nm are realized for 7-PhQAD. These superior results reveal that apart from nitrogen and boron-aromatic systems, QAD framework can also act as a TADF matrix with effective resonance effect, and QAD derivatives are ideal candidates to develop TADF emitters with narrow FWHMs for practical applications.
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A novel thermally activated delayed fluorescence (TADF) emitter 12,15-di(10H-phenoxazin-10-yl)dibenzo[a,c]dipyrido[3,2-h:2',3'-j]phenazine (DPXZ-BPPZ) is developed for a highly efficient red organic light-emitting diode (OLED). With rigid and planar constituent groups and evident steric hindrance between electron-donor (D) and electron-acceptor (A) segments, DPXZ-BPPZ realizes extremely high rigidity to suppress the internal conversion process. Meanwhile, the highly twisted structure between D and A segments will also lead to an extremely small singlet-triplet energy split to DPXZ-BPPZ. Therefore, DPXZ-BPPZ successfully realizes an efficient fluorescent radiation transition and reverse intersystem crossing process, and possesses an extremely high photoluminescence quantum efficiency of 97.1 ± 1.1% under oxygen-free conditions. The OLED based on DPXZ-BPPZ shows red emission with a peak at 612 nm and a Commission Internationale de L'Eclairage (CIE) coordinate of (0.60, 0.40), and it achieves high maximum forward-viewing efficiencies of 20.1 ± 0.2% (external quantum efficiency), 30.2 ± 0.6 cd A-1 (current efficiency), and 30.9 ± 1.3 lm W-1 (power efficiency). The prepared OLED has the best performance among the reported red TADF OLEDs. These results prove that DPXZ-BPPZ is an ideal candidate for red TADF emitters, and the designing approach is valuable for highly efficient red TADF emitters.
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A charge-transfer model considering the mixed conductivities of proton, oxygen ion, and free electron in interface-modified La2Ce2O7 (LCO) electrolyte is designed to analyze the characteristics of proton ceramics fuel cell in the field of the open-circuit voltage, internal short-circuit current, proton-transfer number, discharging curves, oxygen/hydrogen partial pressure, and cell efficiencies. The properties of anode-supported single cells with the modified anode-electrolyte interface containing an in situ formed doped BaCeO3 reaction layer are compared to those of unmodified cells at various temperatures T and H2O partial pressures. Besides, the electrochemical impedance spectroscopies of both cells were investigated by the relaxation time distribution to distinguish different polarization processes. The results indicated that the reaction interface layer can effectively reduce the internal short-circuit current density and increase the proton-transfer number of electrolytes. Importantly, the NiO-BaZr0.1Ce0.7Y0.2O3-δ anode can also make more protons transfer from anode to cathode and participate in the cathodic reaction for LCO-based proton ceramics fuel cell. The polarization of the cell decreases with the increase of water partial pressure, which leads to the increase of open-circuit voltage and cell efficiency.
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In this work, we propose a novel concept to develop two fluorophores 2-(10 H-phenothiazin-10-yl)thianthrene 5,5,10,10-tetraoxide (PTZ-TTR) and 2-(4-(10 H-phenothiazin-10-yl)phenyl)thianthrene 5,5,10,10-tetraoxide (PTZ-Ph-TTR) showing dual conformations for highly efficient single-emitter white organic light-emitting diodes (WOLEDs). Both molecules exist in two stable conformations. Their nearly orthogonal forms own lower energy levels and show thermally activated delayed fluorescence (TADF) characteristics, whereas their nearly planar conformers possess higher energy levels and show only prompt fluorescence. These dual conformers were exploited for fabricating WOLEDs with complementary emission colors contributed by the two conformations. Moreover, the originally wasted triplet energy on the nearly planar conformation can be transferred to the nearly orthogonal one and then harvested via the TADF channel, realizing full exciton utilization. A PTZ-TTR-based single-emitter device exhibits standard white emission with a CIE coordinate of (0.33, 0.33) and a high color rendering index value of 92. On the other hand, the PTZ-Ph-TTR-based single-emitter device realizes an emission approaching warm white light and a high maximum external quantum efficiency of 16.34%. These results demonstrate an alternative approach for designing high-performance WOLEDs based on single TADF emitters.
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A novel molecular model of connecting electron-donating (D) and electron-withdrawing (A) moieties via a space-enough and conjugation-forbidden linkage (D-Spacer-A) is proposed to develop efficient non-doped thermally activated delayed fluorescence (TADF) emitters. 10-(4-(4-(4,6-diphenyl-1,3,5-triazin-2-yl) phenoxy) phenyl)-9,9-dimethyl-9,10-dihydroacridine (DMAC-o-TRZ) was designed and synthesized accordingly. As expected, it exhibits local excited properties in single-molecule state as D-Spacer-A molecular backbone strongly suppress the intramolecular charge-transfer (CT) transition. And intermolecular CT transition acted as the vital radiation channel for neat DMAC-o-TRZ film. As in return, the non-doped device exhibits a remarkable maximum external quantum efficiency (EQE) of 14.7 %. These results prove the feasibility of D-Spacer-A molecules to develop intermolecular CT transition TADF emitters for efficient non-doped OLEDs.
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OBJECTIVES: Due to their increased energy expenditure, chronic obstructive pulmonary disease (COPD) patients with respiratory failure are susceptible to malnutrition. This study aimed to compare the predictive values of the following three widely used nutritional assessment methods for the clinical prognosis of COPD patients with respiratory failure: body mass index (BMI), Nutritional Risk Screening 2002 (NRS 2002), and serum albumin (ALB) level. METHODS: COPD patients with respiratory failure treated in our center from June 2013 to June 2016 were retrospectively included. Patient BMI, NRS 2002 and ALB values were measured to assess their nutritional status. A multivariable analysis was conducted, and receiver operating characteristic (ROC) curves were generated to explore the predictive factors for clinical prognoses. RESULTS: A total of 438 qualified patients were enrolled in our study. Multivariable analysis revealed that the BMI and ALB values independently predicted in-hospital mortality, the BMI and NRS 2002 predicted 1-year mortality, and all three methods (BMI, NRS 2002, and ALB) predicted 30-day readmission after discharge (Pâ¯<â¯0.05). Regarding the results of the AUROC analysis, the optimal cutoff values that maximized the ability to predict the prognosis were an ALB level of 30.5â¯g/L for in-hospital mortality, an NRS 2002 score of 3 points for 1-year mortality, and an ALB level of 30.1â¯g/L for readmission within 30â¯days following discharge. CONCLUSIONS: For COPD patients with respiratory failure, ALB level was superior for predicting in-hospital mortality and 30-day readmission after discharge, and NRS 2002 was superior for long-term prognosis of 1-year mortality.