To develop high‐performance thermally activated delayed fluorescence (TADF) exciplex emitters, a novel strategy of introducing a single‐molecule TADF emitter as one of the constituting materials has ...been presented. Such a new type of exciplex TADF emitter will have two reverse intersystem crossing (RISC) routes on both the pristine TADF molecules and the exciplex emitters, benefiting the utilization of triplet excitons. Based on a newly designed and synthesized single‐molecule TADF emitter MAC, a highly efficient exciplex emitter MAC:PO‐T2T has been obtained. The device based on MAC:PO‐T2T with a weight ratio of 7:3 exhibits a low turn‐on voltage of 2.4 V, high maximum efficiency of 52.1 cd A−1 (current efficiency), 45.5 lm W−1 (power efficiency), and 17.8% (external quantum efficiency, EQE), as well as a high EQE of 12.3% at a luminance of 1000 cd m−2. The device shows the best performance among reported organic light‐emitting devices based on exciplex emitters. Such high‐efficiency and low‐efficiency roll‐off should be ascribed to the additional reverse intersystem crossing process on the MAC molecules, showing the advantages of the strategy described in this study.
A new type of high‐performance exciplex thermally activated delayed fluorescence TADF emitter is demonstrated by introducing single‐molecule TADF emitter as one of the constituting materials. The OLED based on the novel emitter shows a low turn‐on voltage of 2.4 V and a maximum external quantum efficiency of 17.8% with mild efficiency roll‐off, which offers a new strategy for designing efficient exciplex emitters.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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.
The mechanism, exciton leaking channels, and reported molecular design strategies of TADF emitters for high-performance nondoped OLEDs are summarized. Their molecular structures depending on the functional A groups are further classified.
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IJS, KILJ, NUK, UL, UM, UPUK
The pesticide and veterinary drug residues brought by large-scale agricultural production have become one of the issues in the fields of food safety and environmental ecological security. It is ...necessary to develop the rapid, sensitive, qualitative and quantitative methodology for the detection of pesticide and veterinary drug residues. As one of the achievements of nanoscience, quantum dots (QDs) have been widely used in the detection of pesticide and veterinary drug residues. In these methodology studies, the used QD-signal styles include fluorescence, chemiluminescence, electrochemical luminescence, photoelectrochemistry, etc. QDs can also be assembled into sensors with different materials, such as QD-enzyme, QD-antibody, QD-aptamer, and QD-molecularly imprinted polymer sensors, etc. Plenty of study achievements in the field of detection of pesticide and veterinary drug residues have been obtained from the different combinations among these signals and sensors. They are summarized in this paper to provide a reference for the QD application in the detection of pesticide and veterinary drug residues.
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IJS, KILJ, NUK, PNG, UL, UM, UPUK
Ubiquitous contamination of microplastics and arsenic in soil ecosystems can induce many health issues to nontarget soil organisms, and will also cause many potential threats to the gut bacterial ...communities of soil fauna. However, the changes in the gut bacterial communities of soil fauna after exposure to both microplastics and arsenic remain unknown. In this study, the toxicity and effects on the gut microbiota of earthworm Metaphire californica caused by the combined exposure of microplastics and arsenic were examined by using arsenic species analysis and high throughput sequencing of gut microbiota. Results showed that total arsenic and arsenic species in the earthworm gut and body tissues after exposure to combination of microplastics with arsenate (As(V)) were significantly different from that treated with As(V) alone. Microplastics lessened the accumulation of total arsenic and the transformation rate of As(V) to arsenite (As(III)). Microplastics alleviated the effect of arsenic on the gut microbiota possibly via adsorbing/binding As(V) and lowering arsenic bioavailability, thus prevented the reduction of As(V) and accumulation of total arsenic in the gut which resulted in a lower toxicity on the earthworm. The study broadens our understanding of the ecotoxicity of microplastics with other pollutants on the soil animals and on their gut microbiota.
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•Arsenic exposure prominently altered the gut bacterial communities of earthworm.•Microplastics reduced arsenic accumulation in the earthworm gut and body tissues by inhibiting As(V) reduction.•Microplastics alleviated the effect of arsenic on the gut microbiota.
Exposure to microplastics lowers arsenic accumulation in the gut and body tissues of earthworm, and alters gut bacterial communities of Metaphire californica.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A novel thermally activated delayed fluorescence (TADF) emitter 12,15‐di(10H‐phenoxazin‐10‐yl)dibenzoa,cdipyrido3,2‐h:2′,3′‐jphenazine (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.
A thermally activated delayed fluorescence emitter with rigid and planar constituent segments and highly twisted electron‐donor–electron‐acceptor framework for highly efficient red organic light‐emitting diode is developed. It results in an efficient fluorescent radiation transition and reverse intersystem crossing process simultaneously. The device based on this emitter exhibits red emission as well as a high maximum forward‐viewing external quantum efficiency of 20.1 ± 0.2%.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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.
Until now, the influence of the conformational distribution on the photophysics and device performance of thermally activated delayed fluorescence (TADF) emitters has not been clear. Herein, conformational populations in disordered solid states are quantitatively measured for the first time. A high‐performance “self‐doping” OLED with a maximum external quantum efficiency of 25.4 % is achieved.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The enzymatic activities of Furin, Transmembrane serine proteinase 2 (TMPRSS2), Cathepsin L (CTSL), and Angiotensin‐converting enzyme 2 (ACE2) receptor binding are necessary for the entry of ...coronaviruses into host cells. Precise inhibition of these key proteases in ACE2+ lung cells during a viral infection cycle shall prevent viral Spike (S) protein activation and its fusion with a host cell membrane, consequently averting virus entry to the cells. In this study, dual‐drug‐combined (TMPRSS2 inhibitor Camostat and CTSL inhibitor E‐64d) nanocarriers (NCs) are constructed conjugated with an anti‐human ACE2 (hACE2) antibody and employ Red Blood Cell (RBC)‐hitchhiking, termed “Nanoengineered RBCs,” for targeting lung cells. The significant therapeutic efficacy of the dual‐drug‐loaded nanoengineered RBCs in pseudovirus‐infected K18‐hACE2 transgenic mice is reported. Notably, the modular nanoengineered RBCs (anti‐receptor antibody+NCs+RBCs) precisely target key proteases of host cells in the lungs to block the entry of Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), regardless of virus variations. These findings are anticipated to benefit the development of a series of novel and safe host‐cell‐protecting antiviral therapies.
Dual‐drug‐combined (Camostat and E‐64d) nanocarriers (NCs) are constructed, conjugated with an anti‐hACE2 antibody and employed RBC‐hitchhiking, termed “Nanoengineered RBCs”, for effectively blocking SARS‐CoV‐2 cell entry in the lungs, regardless of virus variations. The nano‐micro system is modular (anti‐receptor antibody + drug‐loaded NCs + RBCs), and the findings will benefit the development of a series of novel and safe host‐cell‐protecting antiviral therapies.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background
Assessing hepatic functional reserve before hepatectomy is beneficial to reduce the incidence of posthepatectomy liver failure (PHLF). This study aimed to compare the ability of the ...Child‐Pugh score, model for end‐stage liver disease (MELD) score, and retention test at 15 minutes (indocyanine green ICG‐R15) to assess hepatic functional reserve.
Methods
A total of 185 patients with hepatocellular carcinoma (HCC) undergoing hepatectomy were enrolled in this study. The ability of Child‐Pugh score, MELD score, and ICG‐R15 predicting severe PHLF were compared.
Results
A total of 23 patients (12.4%) developed severe PHLF. Multivariate analyses identified that platelet count, ICG‐R15, clinically significant portal hypertension, and major resection were independent factors for predicting severe PHLF. The area under the receiver operating characteristic curve of ICG‐R15 for predicting severe PHLF was higher than that of both Child‐Pugh score and MELD score. With an optimal cutoff value of 7.1%, the sensitivity and specificity of ICG‐R15 for predicting severe PHLF were 52.2% and 89.5%, respectively. Both the incidence of severe PHLF and mortality in patients with ICG‐R15 >7.1% were significantly higher than the figures for patients with ICG‐R15 ≤7.1%.
Conclusion
ICG‐R15 is more accurate than the Child‐Pugh score and MELD score in predicting hepatic functional reserve before hepatectomy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
With the increased incidence of wine fraud, a fast and reliable method for wine certification has become a necessary prerequisite for the vigorous development of the global wine industry. In this ...study, a classification strategy based on three-dimensional fluorescence spectroscopy combined with chemometrics was proposed for oak-barrel and stainless steel tanks with oak chips aged wines. Principal component analysis (PCA), partial least squares analysis (PLS-DA), and Fisher discriminant analysis (FDA) were used to distinguish and evaluate the data matrix of the three-dimensional fluorescence spectra of wines. The results showed that FDA was superior to PCA and PLS-DA in classifying oak-barrel and stainless steel tanks with oak chips aged wines. As a general conclusion, three-dimensional fluorescence spectroscopy can provide valuable fingerprint information for the identification of oak-barrel and stainless steel tanks with oak chips aged wines, while the study will provide some theoretical references and standards for the quality control and quality assessment of oak-barrel aged wines.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Hepatocellular carcinoma (HCC) is one of the deadliest cancers. Multiple long non‐coding RNAs (lncRNAs) are recently identified as crucial oncogenic factors or tumour suppressors. In this study, we ...explored the effects of LINC00174 on the progression of HCC. Expression levels of LINC00174 and microRNA‐320 (miR‐320) in HCC tissue samples were measured using quantitative real‐time polymerase chain reaction (qRT‐PCR). The association between pathological indices and LINC00174 was also analysed. Human HCC cell lines Hep3B and Huh7 were used as cell models. CCK‐8 and bromodeoxyuridine (BrdU) assays were used to assess the effect of LINC00174 on HCC cell line proliferation. Flow cytometry was used to study the effect of LINC00174 on HCC apoptosis. Transwell assay was conducted to detect the effect of LINC00174 on migration and invasion. Furthermore, luciferase reporter assay and RNA immunoprecipitation (RIP) assay were used to confirm the binding relationship between miR‐320 and LINC00174. Additionally, western blot was used to detect the regulatory function of LINC00174 on oncogene S100 calcium binding protein A10 (S100A10). We demonstrated that LINC00174 expression in HCC clinical samples was significantly increased and this was correlated with higher T stage. Its overexpression remarkably accelerated proliferation and metastasis of HCC cells while reduced apoptosis. Accordingly, knockdown of it suppressed the malignant phenotypes of HCC cells. Overexpression of LINC00174 significantly reduced the expression of miR‐320 by sponging it, in turn enhanced the expression of S100A10. In conclusion, LINC00174 is a sponge of tumour suppressor miR‐320, enhances the expression of S100A10 indirectly and functions as an oncogenic lncRNA in HCC.
Significance of the study
LINC00174 is a novel lncRNA, whose function is rarely investigated. It is reported that it is oncogenic in colorectal cancer, while its role in HCC remains unclear. Herein, we report that LINC00174 is significantly up‐regulated in HCC tissues and promotes the malignant phenotypes. We demonstrate that LINC00174 functions as a sponge for miR‐320, increases the expression level of oncogene S100A10 in HCC. This study helps clarify the mechanism of HCC tumorigenesis and progression, and uncover the role of LINC00174 in human disease.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK