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1.
Am J Med Sci ; 365(2): 169-175, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36167155

RESUMEN

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.


Asunto(s)
Neutrófilos , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Progresión de la Enfermedad , Readmisión del Paciente , Estudios Retrospectivos , Linfocitos
2.
Angew Chem Int Ed Engl ; 61(42): e202210613, 2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36064999

RESUMEN

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 1200 h under operation or thermal aging at 85 °C.

3.
Chem Sci ; 13(13): 3625-3651, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35432901

RESUMEN

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.

4.
Bull Cancer ; 109(6): 642-647, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34657726

RESUMEN

AIM: To investigate the therapeutic effect of Elemene combined with Nedaplatin (ECN) on malignant pleural effusion (MPE) and its adverse reactions. METHOD: A retrospective study was conducted, three hundred and fifty-two patients with MPE were divided into two groups according to different treatment methods. One hundred and eighty-nine patients were given intrathoracic injection of ECN and classified in ECN group; one hundred and sixty-three cases in the Nedaplatin group were given intrathoracic injection of nedaplatin. Routine treatments were used to prevent adverse reactions. RESULT: The effective rate of the ECN group was 57.05%, and that of the Nedaplatin group was 23.08%. The comparison results of adverse reactions between the two groups showed that there was no significant difference in leukopenia, thrombopenia, anemia, vomitting and diarrhea, fever, hepatic damage and renal damage. The level of thoracalgia in the ECN group was higher than that in the Nedaplatin group. There was no significant change in the number of CD8+ T cells between the two groups after treatment. The number of CD4+T cells in the ECN group increased after treatment was higher than the Nedaplatin group after treatment. CONCLUSION: ECN treatment can improve clinical control of MPE with no serious adverse reaction, can effectively reduce the immunosuppressive effect of nedaplatin and enhance the immune function of MPE patients which is worthy of clinical application.


Asunto(s)
Derrame Pleural Maligno , Humanos , Compuestos Organoplatinos/efectos adversos , Derrame Pleural Maligno/tratamiento farmacológico , Estudios Retrospectivos , Sesquiterpenos
5.
Angew Chem Int Ed Engl ; 60(49): 25878-25883, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34585471

RESUMEN

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.

6.
Chem Sci ; 12(4): 1495-1502, 2020 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34163913

RESUMEN

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.

7.
Int J Chron Obstruct Pulmon Dis ; 14: 2725-2731, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31819404

RESUMEN

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.


Asunto(s)
Broncodilatadores/administración & dosificación , Budesonida/administración & dosificación , Glucocorticoides/administración & dosificación , Pulmón/efectos de los fármacos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Administración por Inhalación , Anciano , Anciano de 80 o más Años , Broncodilatadores/efectos adversos , Budesonida/efectos adversos , China , Progresión de la Enfermedad , Femenino , Volumen Espiratorio Forzado , Glucocorticoides/efectos adversos , Humanos , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Nebulizadores y Vaporizadores , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Recuperación de la Función , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
8.
ACS Appl Mater Interfaces ; 11(14): 13472-13480, 2019 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-30892014

RESUMEN

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.

9.
Adv Sci (Weinh) ; 5(9): 1800436, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30250791

RESUMEN

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.

10.
ACS Appl Mater Interfaces ; 10(37): 31515-31525, 2018 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-30132326

RESUMEN

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.

11.
Angew Chem Int Ed Engl ; 57(30): 9480-9484, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-29863299

RESUMEN

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.

12.
Adv Mater ; 29(47)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29116652

RESUMEN

The recent introduction of thermally activated delayed fluorescence (TADF) emitters is regarded as an important breakthrough for the development of high efficiency organic light-emitting devices (OLEDs). The planar D and A groups are generally used to construct TADF emitters for their rigid structure and large steric hindrance. In this work, it is shown that many frequently used nonaromatic (noncontinuous conjugation or without satisfying Hückel's rule) planar segments, such as 9,9-dimethyl-9,10-dihydroacridine, are actually pseudoplanar segments and have two possible conformations-a planar form and a crooked form. Molecules constructed from pseudoplanar segments can thus have two corresponding conformations. Their existence can have significant impact on the performance of many TADF emitters. Two design strategies are presented for addressing the problem by either (1) increasing the rigidity of these groups to suppress its crooked form or (2) increasing the steric hindrance of the linked group to minimize energy of the emitters with the highly twisted form. Following these strategies, two new emitters are synthesized accordingly and successfully applied in OLEDs demonstrating high external quantum efficiencies (20.2% and 18.3%).

13.
ACS Appl Mater Interfaces ; 9(10): 8848-8854, 2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-28218516

RESUMEN

Thermally activated delayed fluorescence (TADF) emitters have attracted much interest for their great applications in organic light-emitting diodes (OLEDs), but the TADF OLEDs are limited by large efficiency roll-offs. In this study, we report two coumarin-based TADF emitters, 3-methyl-6-(10H-phenoxazin-10-yl)-1H-isochromen-1-one (PHzMCO) and 9-(10H-phenoxazin-10-yl)-6H-benzo[c]chromen-6-one (PHzBCO), with relatively high photoluminescence quantum yields (PLQYs) and extremely small singlet-triplet splittings. OLEDs using these two TADF compounds as the emitters respectively demonstrate high external quantum efficiencies of 17.8% for PHzMCO and 19.6% for PHzBCO, which are the highest among the reported coumarin-derivative-based OLEDs. More importantly, these devices based on PHzMCO and PHzBCO remained 10.3% and 12.9% at 10000 cd m-2, respectively, showing relatively low efficiency roll-offs at high brightness. These results reveal that the TADF emitters with high PLQYs can effectively reduce the efficiency roll-off in the devices.

14.
ACS Appl Mater Interfaces ; 8(48): 32984-32991, 2016 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-27934186

RESUMEN

Thermally activated delayed fluorescence (TADF) emitters of different colors commonly need different hosts, which cause the complexed device structure and low efficiency of all fluorescence white organic light-emitting devices (F-WOLEDs). To solve this, novel concept of employing TADF exciplex as universal host of TADF emitters with different colors was proposed. All blue, green, and orange devices based on the TADF exciplex host show much lower turn-on voltages, and comparable and even higher efficiencies than corresponding devices based on conventional hosts. The two color F-WOLED with extremely simplified device structure was finally fabricated, achieving a white emission with the maximum current efficiency (CE), power efficiency (PE), and external quantum efficiency (EQE) respectively of 50.1 cd A-1, 63.0 lm W-1, and 19.0% in the forward-viewing direction without any light out-coupling technology, which is the best performance among reported F-WOLEDs, demonstrating the superiority of the novel concept.

15.
ACS Appl Mater Interfaces ; 8(26): 16791-8, 2016 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-27296853

RESUMEN

To improve the color purity of thermally activated delayed fluorescence (TADF) emitters, two isomeric compounds, oPTC (5'-(phenoxazin-10-yl)-[1,1':3',1″-terphenyl]-2'-carbonitrile) and mPTC (2'-(phenoxazin-10-yl)-[1,1':3',1″-terphenyl]-5'-carbonitrile), were designed and synthesized with same skeleton but different molecular restrictions. Both compounds exhibit similar highest occupied molecular orbital and lowest unoccupied molecular orbital distributions and energy levels, photophysical properties in nonpolar cyclohexane solution, and high external quantum efficiencies (19.9% for oPTC and 17.4% for mPTC) in the devices. With the increased molecular space restriction induced by the additional phenyl substitutions at meta-position of the cyano group from mPTC to oPTC, much weaker positive solvatochromic effect is observed for mPTC. And the color purity of emission from mPTC (full width at half-maximum (fwhm) of 86 nm) is also improved contrasted with that of oPTC (fwhm of 97 nm) in the devices. These results prove that increased restriction of the molecular structure is a simple and effective method to improve the color purity of the TADF emitters.

16.
Nanoscale ; 8(4): 2123-8, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26725832

RESUMEN

Silicon is the dominant semiconductor in modern society, but the rigid nature of most Si structures hinders its applications in flexible electronics. In this work, Si-based flexible strain sensors are fabricated with Si fabric consisting of long Si nanowires. The as-obtained sensors demonstrate a large strain range of 50% and a gauge factor of up to 350, which are sufficient to detect human motions with superior performance over traditional sensors. The results reveal that the assembling strategy may potentially be applied to large-scale fabrication of highly sensitive, flexible strain sensors for emerging applications such as healthcare and sports monitoring. Moreover, the Si fabric would also enable broad applications of Si materials in other flexible and wearable devices such as flexible optoelectronics and displays.


Asunto(s)
Locomoción , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Nanocables , Silicio , Humanos
17.
Chem Commun (Camb) ; 52(7): 1369-72, 2016 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-26616404

RESUMEN

We demonstrate the first systematic study of the diameter-dependent photoelectrochemical performance of single silicon nanowires within a broad size range from 200 to 2000 nm. SiNWs with a diameter of 1415 nm exhibit the highest solar energy conversion efficiency, which can be mainly traced to their diameter-dependent light absorption properties.


Asunto(s)
Técnicas Electroquímicas/métodos , Nanocables , Procesos Fotoquímicos , Silicio/química
19.
ACS Appl Mater Interfaces ; 7(34): 18930-6, 2015 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-26289611

RESUMEN

A novel blue thermally activated delayed fluorescence (TADF) emitter, CPC (2,6-di(9H-carbazol-9-yl)-4-phenylpyridine-3,5-dicarbonitrile), was designed and synthesized. By directly linking carbazole (to serve as electron-donor) and pyridine-3,5-dicarbonitrile (to serve as electron-acceptor), and distributing cyanogroups and carbazole groups at the para-position of pyridine core, CPC successfully achieves an extremely small singlet-triplet splitting and fairish photoluminescence quantum yield, thus can act as the highly efficient blue TADF emitter. The optimized organic light-emitting diode (OLED) based on 13 wt % CPC doped in mCP (1,3-bis(9H-carbazol-9-yl)benzene) host exhibits maximum current efficiency, power efficiency, and external quantum efficiency of 47.7 cd A(-1), 42.8 lm W(-1), and 21.2%, respectively, which are the best results in reported blue TADF-based devices up to date and even comparable with the best reported blue phosphorescent OLEDs.

20.
Adv Mater ; 27(14): 2378-83, 2015 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-25712786

RESUMEN

High-efficiency, thermally activated delayed-fluorescence organic light-emitting diodes based on exciplex emitters are demonstrated. The best device, based on a TAPC:DPTPCz emitter, shows a high external quantum efficiency of 15.4%. Strategies for predicting and designing efficient exciplex emitters are also provided. This approach allow prediction and design of efficient exciplex emitters for achieving high-efficiency organic light-emitting diodes, for future use in displays and lighting applications.

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