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Fast spin-flipping is the key to exploit the triplet excitons in thermally activated delayed fluorescence based organic light-emitting diodes toward high efficiency, low efficiency roll-off and long operating lifetime. In common donor-acceptor type thermally activated delayed fluorescence molecules, the distribution of dihedral angles in the film state would have significant influence on the photo-physical properties, which are usually neglected by researches. Herein, we find that the excited state lifetimes of thermally activated delayed fluorescence emitters are subjected to conformation distributions in the host-guest system. Acridine-type flexible donors have a broad conformation distribution or bimodal distribution, in which some conformers feature large singlet-triplet energy gap, leading to long excited state lifetime. Utilization of rigid donors with steric hindrance can restrict the conformation distributions in the film to achieve degenerate singlet and triplet states, which is beneficial to efficient reverse intersystem crossing. Based on this principle, three prototype thermally activated delayed fluorescence emitters with confined conformation distributions are developed, achieving high reverse intersystem crossing rate constants greater than 106 s−1, which enable highly efficient solution-processed organic light-emitting diodes with suppressed efficiency roll-off.

Biomacromolecules such as enzymes and proteins with bactericidal activity are promising for antibacterial applications in a mild, biocompatible, and environmentally friendly manner. However, low bactericidal efficiency has hindered its applications. Nanobiohybrids, constructed from biomacromolecules and functional nanomaterials, could enhance the function of biomacromolecules. However, the incompatibility between biological components and nanomaterials is still the major challenge of designing nanobiohybrids. Here, we rationally design lysozyme-Ag-polymer nanocomposites, which display high stability and antibacterial activity in a cooperative manner. The sufficient presence of Ag-N coordination between Ag and the polymer/protein contributed to the high stability of the nanocomposites. Compared with lysozyme and commercial silver nanoparticles (AgNPs) alone, the enzyme-Ag-polymer nanocomposites showed dramatically enhanced antibacterial activity. We propose a tightly encapsulated invasion (TEI) mechanism for a greatly improved antibacterial activity. The bacteria closely interacted with nanocomposites, and cell walls were hydrolyzed by lysozyme especially, facilitating the penetration of silver into the bacteria, and then reactive oxygen species (ROS) generated by silver to kill bacteria. In addition, the specific TEI mechanism resulted in high biocompatibility toward mammalian cells.

The majority of the literature has focused on the impact of diversification on bank performance, while the research on the impact of diversification on bank costs is inadequate. Therefore, in this paper we empirically analyzed the impact of diversification on operating costs through a panel regression model, collecting the data of 47 Chinese commercial banks from 2005 to 2015. The empirical results showed that an increase in the non-interest income ratio significantly promoted a decrease in the cost–income ratio, and the robustness tests of different time intervals and different types of banks were consistent. This suggests that diversification effectively reduced the operating costs of banks by means of the sharing of information and equipment, the reduction of asset specificity, and the improvement of operation management synergy. This also indicates that excessive competition costs and the agency costs of diversification were lower. Further analysis showed that the diversification of national banks compared with local banks was more significant in reducing operating costs, and, for the national banks, the effects of economies of scope and scale were stronger. Diversified management strategies for local banks should be carefully promoted through the construction of strategic alliances, mergers and acquisitions, etc.

Highly efficient organic thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP) emitters for organic light-emitting diodes (OLEDs) generally consist of a twisted donor-acceptor skeleton with aromatic amine donors. Herein, through introducing sulfur atoms into isomeric pentaphene and pentacene frameworks, we demonstrate a set of polycyclic luminophores exhibiting efficient TADF and RTP characters. The incorporation of sulfur atoms confirms a folded molecular plane, while intensifies singlet-triplet spin-orbit coupling. Further, the isomeric effect has a significant effect on the electronic structure of excited state, giving rise to the investigated compounds tunable luminescence mechanisms of TADF and RTP. With efficient triplet harvesting ability, maximum external quantum efficiencies up to 25.1 % and 8.7 % are achieved for the corresponding TADF and RTP OLEDs, verifying the great potential of sulfur-bridged frameworks for highly efficient devices.

Purely organic materials usually exhibit weak spin-orbital coupling (SOC) effect because of the lack of noble heavy metals, and the generation and direct emission from the triplet state is spin-forbidden. This would lead to slow intersystem crossing, long triplet lifetime, and low phosphorescence quantum yield. Herein, strong spin-orbital coupling between singlet and triplet was observed in a "flexible" and twist thianthrene-pyrimidine-based purely organic compound in an amorphous film state, which shows a fast intersystem crossing process and a high phosphorescence rate of 1.1 × 10

Magnetic skyrmions, as spintronic information carriers, are promising for next-generation spin logic and memory devices. For such skyrmion-based devices, effective control of skyrmion nucleation and controllable motion in the nanotrack are of great importance. The ion irradiation process can modify magnetic properties, such as perpendicular magnetic anisotropy (PMA) and Dzyaloshinskii–Moriya interaction (DMI), at the nanoscale, which can be used to reduce the design complexity of devices. In this study, a nanoregion without PMA in the nanotrack is adopted as a skyrmion nucleation seed and a current-driven highly efficient, in-line, and on-demand skyrmion nucleation schematic is presented. A key factor for realizing this concept is that the disappearance of PMA and the existence of DMI induce magnetization tilts and create a chiral perpendicular stripe domain within the nucleation region. This stripe domain allows the effective control of the spin transfer torque, and it is ejected from the PMA-modified region and propelled into the nanotrack, forming a stable skyrmion. Our proposed device allows the controlled nucleation and propagation of a series of skyrmions, which allows binary information to be written in a controlled manner, consequently, yielding simple devices with two terminals. This study provides an efficient route for designing tunable skyrmionics-mechanic memory devices.

There exist communication barriers between the deaf people and the listeners. Sign language translation is a reasonable and effective way to break these barriers. Recognition of sign language symbols is an essential part of sign language translation. Sign language digits of (0–9) and alphabetic letters of (A–Z) are elementary but important symbols of sign languages of different countries or regions. Capsule networks (CapsNet) are promising alternative to convolutional neural networks (CNN), which take into account of the spatial relationships and orientations of the features of an entity. For sign language digits and alphabets recognition tasks, the proposed SLR-CapsNet architecture achieves a start-of-the-art test accuracy of 99.52% with 100*100 RGB input size and 99.94% with 32*32 RGB input size on Sign Language Digits Dataset and 99.60% with 28*28 Gray-scale input on Sign Language MNIST Dataset. The experimental results also prove that CapsNet has higher generalization and expressiveness capacity on unseen data than CNN dose. Another important finding in our work is that SLR-CapsNet is robust to routing iterations, i.e., its performance will not be affected by various routing iterations.

Luminescence behaviors in organic emitters are influenced greatly by the molecular conformation. However, the current research on room-temperature phosphorescence (RTP) mainly focuses on fixed molecular conformation, such as that in single crystals and rigid hosts. Herein, by linking the phenothiazine moiety with nitrogen heterocycles, we constructed four phenothiazine derivates having planar structure in the ground state. In the excited state, a large conformation relaxation occurs to give a dynamically tunable fluorescence and phosphorescence by the extent of the intramolecular charge transfer (ICT). In systems with a reduced ICT character, multiple emissions consisting of fluorescence and phosphorescence were observed and a white light emission was obtained in the amorphous film state. When increasing the ICT, strong spin mixing between the singlet and triplet occurs in the twisted intramolecular charge transfer (TICT) state, which is favorable for a short triplet lifetime. The emission of the thermally activated delayed fluorescence (TADF) or short RTP depends on the allowance or forbidden of fluorescence in the twisted excited state conformation. This work demonstrates the adjustment of the singlet and triplet emission behaviors through controlling the extent of TICT and provides an insight into the relationship between the molecular conformation and triplet exciton dynamics for future applications.

Long noncoding RNAs (lncRNAs) regulate cancer progression and drug resistance. However, the role of lncRNA FGD5-AS1 in regulating colon cancer (CC) progression is still largely unknown. Hence, this study investigated the role of lncRNA FGD5-AS1 in regulating colon cancer (CC) progression and found that lncRNA FGD5-AS1 regulated miR-497-5p/PD-L1 axis to promote cancer progression in CC cells in vitro and in vivo. Specifically, we found that lncRNA FGD5-AS1 and PD-L1 tended to be high-expressed, while miR-497-5p was low-expressed in CC tissues and cell lines compared to the normal adjacent tissues and cells. Next, we found that lncRNA FGD5-AS1 positively regulated PD-L1 in CC cells by sponging miR-497-5p. Finally, our gain- and loss-of-function experiments evidenced that the lncRNA FGD5-AS1/miR-497-5p/PD-L1 axis regulates CC progression. Functionally, the data suggested that lncRNA FGD5-AS1 positively regulated while miR-497-5p negatively modulated malignant phenotypes, including cell proliferation, viability, invasion, migration, epithelial-mesenchymal transition (EMT), and tumorigenesis in CC cells. Interestingly, the inhibiting effects of lncRNA FGD5-AS1 ablation on CC development were abrogated by both silencing miR-497-5p and upregulating PD-L1. This study found that lncRNA FGD5-AS1 sponged miR-497-5p to upregulate PD-L1, resulting in CC progression, and provided novel agents for CC diagnosis and prognosis.

Versatile host materials with good chemical stability and carrier-transporting ability are quite responsible for achieving stable solution-processed thermally activated delayed fluorescence (TADF) organic light-emitting diodes (OLEDs). Herein, we reported three bipolar dendritic hosts with or without the electron-withdrawing pyridine moiety via 6-site-linkages, namely, 3,3'-bis(3,3″,6,6″-tetra-tert-butyl-9'H-[9,3':6',9″-tercarbazol]-9'-yl)-1,1'-biphenyl (mCDtCBP), 3,3″,6,6″-tetra-tert-butyl-9'-(6-(3-(3,3″,6,6″-tetra-tert-butyl-9'H-[9,3':6',9″-tercarbazol]-9'-yl)phenyl)pyridine-2-yl)-9'H-9,3':6',9″-tercarbazole (mCDtCBPy), and 6,6'-bis(3,3″,6,6″-tetra-tert-butyl-9'H-[9,3':6',9″-tercarbazol]-9'-yl)-2,2'-bipyridine (mCDtCBDPy), exhibiting outstanding solubility, thermal stability as well as electrochemical stability. According to the calculation of bond dissociation energy (BDE), photodegradation results, and carrier dynamics evaluation, a significant relationship between device stability and the pyridine-based dendritic hosts was uncovered. Using mCDtCDPy with the highest electron mobility as the host, the solution-processed bluish-green TADF-OLED showed the shortest operational lifetime due to the unbalanced charge fluxes despite its highest anionic BDE for good chemical stability. However, the device based on mCDtCBPy exhibited twice longer lifetime than that based on mCDtCBP in spite of their similar balanced charge transportation, highlighting the importance of higher anionic BDE of the C-N bond in the device degradation process. Our findings unveiled a potential approach to achieve a subtle regulation of chemical stability and carrier transportation for realizing stable solution-processed TADF-OLEDs.

SUMMARYNeurodegenerative diseases are characterized by neuronal death and regenerative failure. However, gene regulatory programs governing how initial neuronal injuries lead to neuronal death remain poorly understood. In adult mice, optic nerve crush (ONC) injury, which severs all axons of retinal ganglion cells (RGCs), results in massive death of axotomized RGCs and regenerative failure of survivors. We performed an in vivo CRISPR/Cas9-based genome-wide screen of 1893 transcription factors (TFs) to seek repressors of RGC survival and axon regeneration following ONC. In parallel, we profiled the epigenetic and transcriptional landscapes of injured RGCs by ATAC-seq and RNA-seq to identify critical injury responsive TFs and their targets. Remarkably, these independent analyses converged on a set of four ATF/CEBP transcription factors – ATF3, ATF4, C/EBPγ and CHOP (Ddit3) – as critical regulators of survival. Further studies indicate that these TFs contribute to two pro-death transcriptional programs: ATF3/CHOP preferentially regulate pathways activated by cytokines and innate immunity, whereas ATF4/C/EBPγ regulate pathways engaged by intrinsic neuronal stressors. Manipulation of these TFs also protects RGCs in an experimental model of glaucoma, a prevalent disease in which RGCs die. Together, our results reveal core transcription programs that transform an initial axonal insult into a degenerative result and suggest novel strategies for treating neurodegenerative diseases.

Incorporating chiral organic compounds into metal halide frames is a common and useful method to introduce chirality in metal halide composites. The structures of resulting racemic and chiral composites are usually considered to be nearly identical owing to similar chemical bonding. In this work, by incorporating chiral MBABr (bromide methylbenzylamine) into an inorganic frame, a significant crystallization difference between the resulting racemic and chiral metal halide composites is observed, as confirmed by both structural and spectroscopic measurements. In addition, the structural transformation in the chiral composites can also be induced by moisture, ascribed to the asymmetric hydrogen bonding in chiral materials. These results provide new insights for the future synthesis of chiral materials and open up new possibilities to advance the materials functionalities. Funding Agencies|Knut and Alice Wallenberg Foundation [KAW 2019.0082]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]; China Scholarship Council (CSC)

Despite the increasing prevalence of obesity, the current medications, which act indirectly on the central nervous system to suppress appetite or on the gastrointestinal tract to inhibit fat absorption, suffer from poor effectiveness and side effects. Here, we developed a transdermal mild photothermal therapy directly acting on the root of evil (subcutaneous white adipose depot) to induce its ameliorating remodeling (browning, lipolysis, and apoptosis), based on the injectable thermoresponsive hydrogel encapsulated with copper sulfide nanodots. Further, combining pharmaceutical therapy with codelivery of mirabegron leads to a strong therapeutic synergy. This method not only ensures high effectiveness and low side effects due to localized and targeted application but also remotely creates significant improvements in systemic metabolism. Specifically, as compared to the untreated group, it totally inhibits obesity development in high-fat-diet fed mice (15% less in body weight) with decreased masses of both subcutaneous (40%) and visceral fats (54%), reduced serum levels of cholesterol (54%)/triglyceride (18%)/insulin (74%)/glucose (45%), and improved insulin sensitivity (65% less in insulin resistance index). This self-administrable method is amenable for long-term home-based treatment. Finally, multiple interconnected signaling pathways are revealed, providing mechanistic insights to develop effective strategies to combat obesity and associated metabolic disorders. Accepted version

Human telomeres are protected by shelterin proteins, but how telomeres maintain a dynamic structure remains elusive. Here, we report an unexpected activity of POT1 in imparting conformational dynamics of the telomere overhang, even at a monomer level. Strikingly, such POT1-induced overhang dynamics is greatly enhanced when TRF2 engages with the telomere duplex. Interestingly, TRF2, but not TRF2ΔB, recruits POT1-bound overhangs to the telomere ds/ss junction and induces a discrete stepwise movement up and down the axis of telomere duplex. The same steps are observed regardless of the length of the POT1-bound overhang, suggesting a tightly regulated conformational dynamic coordinated by TRF2 and POT1. TPP1 and TIN2 which physically connect POT1 and TRF2 act to generate a smooth movement along the axis of the telomere duplex. Our results suggest a plausible mechanism wherein telomeres maintain a dynamic structure orchestrated by shelterin.

Patients with locally advanced colorectal cancer (LACRC) have a high risk of recurrence and metastasis, although neoadjuvant therapy may provide some benefit. However, patients with high microsatellite instability/deficient mismatch repair (MSI-H/dMMR) LACRC receive little benefit from neoadjuvant chemoradiotherapy (nCRT) or neoadjuvant chemotherapy (nCT). The 2015 KEYNOTE-016 trial identified MSI-H/dMMR as a biomarker indicative of immunotherapy efficacy, and pointed to the potential use of immune checkpoint inhibitors (ICIs). In 2017, the FDA approved two ICIs (pembrolizumab and nivolumab) for treatment of MSI-H/dMMR metastatic CRC (mCRC). In 2018, the CheckMate-142 trial demonstrated successful treatment of mCRC based on “double immunity” provided by nivolumab with ipilimumab, a regimen that may become a standard first-line treatment for MSI-H mCRC. In 2018, the FDA approved nivolumab alone or with ipilimumab for patients who progressed to MSI-H/dMMR mCRC after standard chemotherapy. The FDA then approved pembrolizumab alone as a first-line treatment for patients with MSI-H/dMMR CRC that was unresectable or metastatic. There is now interest in using these drugs in neoadjuvant immunotherapy (nIT) for patients with MSI-H/dMMR non-mCRC. In 2020, the NICHE trial marked the start of using nIT for CRC. This novel treatment of MSI-H/dMMR LACRC may change the approaches used for neoadjuvant therapy of other cancers. Our review of immunotherapy for CRC covers diagnosis and treatment, clinical prognostic characteristics, the mechanism of nIT, analysis of completed prospective and retrospective studies, and ongoing clinical trials, and the clinical practice of using nIT for MSI-H/dMMR LACRC. Our team also proposes a new organ-preservation strategy for patients with MSI-H/dMMR low LARC.

The host–guest doping system has aroused great attention due to its promising advantage in stimulating bright and persistent room-temperature phosphorescence (RTP). Currently, exploration of the explicit structure–property relationship of bicomponent systems has encountered obstacles. In this work, two sets of heterocyclic isomers showing promising RTP emissions in the solid state were designed and synthesized. By encapsulating these phosphors into a robust phosphorus-containing host, several host–guest cocrystalline systems were further developed, achieving highly efficient RTP performance with a phosphorescence quantum efficiency (ϕP) of ∼26% and lifetime (τP) of ∼32 ms. Detailed photophysical characterization and molecular dynamics (MD) simulation were conducted to reveal the structure–property relationships in such bicomponent systems. It was verified that other than restricting the molecular configuration, the host matrix could also dilute the guest to avoid concentration quenching and provide an external heavy atom effect for the population of triplet excitons, thus boosting the RTP performance of the guest., Several host–guest cocrystal systems with bright and persistent room-temperature phosphorescence were developed by utilizing a phosphorus-containing material as a robust host and newly developed isomeric organic phosphors as guests.

A fast radiative rate, highly suppressed nonradiation, and a short exciton lifetime are key elements for achieving efficient thermally activated delayed fluorescence (TADF) organic light-emitting diodes (OLEDs) with reduced efficiency roll-off at a high current density. Herein, four representative TADF emitters are designed and synthesized based on the combination of benzophenone (BP) or 3-benzoylpyridine (BPy3) acceptors, with dendritic 3,3″,6,6″-tetra

Blue thermally activated delayed fluorescence (TADF) emitters that can simultaneously achieve high efficiency in doped and nondoped organic light-emitting diodes (OLEDs) are rarely reported. Reported here is a strategy using a tri-spiral donor for such versatile blue TADF emitters. Impressively, by simply extending the nonconjugated fragment and molecular length, aggregation-caused emission quenching (ACQ) can be greatly alleviated to achieve as high as a 90 % horizontal orientation dipole ratio and external quantum efficiencies (EQEs) of up to 33.3 % in doped and 20.0 % in nondoped sky-blue TADF-OLEDs. More fascinatingly, a high-efficiency purely organic white OLED with an outstanding EQE of up to 22.8 % was also achieved by employing TspiroS-TRZ as a blue emitter and an assistant host. This compound is the first blue TADF emitter that can simultaneously achieve high electroluminescence (EL) efficiency in doped, nondoped sky-blue, and white TADF-OLEDs.

Hypercrosslinked polymers (HCPs) are a class of promising materials for heterogeneous catalysis in recent years due to their superior physicochemical properties. Herein, a phosphorus-rich network polymer was synthesized by anhydrous FeCl3 promoted Friedel-Crafts alkylation tris(2-thienyl)phosphine and thiophene. Ruthenium (Ru) nanoparticles supported on this polymer was prepared by in-situ reduction method, which exhibits high catalytic activity for catalytic reduction of nitroarenes at room temperature using NaBH4 as reductant. The catalyst can be readily recovered and reused without obvious loss of catalytic activity.

Four novel spiro[fluorene-9,9‘-thioxanthene] core based wide-energy-gap compounds Cz-S, 2Cz-S, Cz-SO2, and 2Cz-SO2 were developed as host materials for a general thermally activated delayed fluorescence (TADF) emitter (4s, 6s)-2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN). The excited states of the sulfane-containing Cz-S and 2Cz-S are in local emission (LE) states while those of the sulfonyl-containing Cz-SO2 and 2Cz-SO2 are in charge transfer (CT) states. The device based on 2Cz-S exhibits the highest efficiency among them with a maximal current efficiency (CE) of 52.1 cd/A and a maximal external quantum efficiency (EQE) of 16.5% due to the largest radiative triplet exciton utilization capacity through intersystem crossing from T1 to S1. In addition, the devices based on Cz-SO2 and 2Cz-SO2 exhibit obviously reduced efficiency roll-off due to their improved carrier balance in a wide current density range, and their J0 (the current density at the half maximum of the EQE) values reach as high as 93 and 115 mA/cm2. It is also of interest their EL spectra are independent on the host dipole moment due to the spiro-conformation that may reduce the interaction between host and dopant.

Ten thiophene derivatives monomers were designed based on thiophene-linker-thiophene platform and were subjected to C Br/C H bulk polycondensation. All of them were converted to corresponding polythiophene derivatives smoothly, indicating that up to three-building-blocks of thiophene monomers can be successfully constructed. Detailed characterizations of the obtained polymers were carried out by regular measurements, including Cyclic Voltammetry (CV), Infrared spectrum (IR), UV–Vis absorbance spectroscopy, TGA and so on. In addition, the obtained poly{phenyl-bis-(4-thiophen-2-yl-phenyl)-amine} was employed as acid sensor and the results showed that HNO3 acid could be recognized and distinguished successfully. Furthermore, a prototype monomer crystal of 2-bromo-3-(9,9-dimethyl-9H-fluoren-2-yl)-thiophene is obtained and its effective reaction points distance (4.197 A) is longer (37.6%) than the van der Waals radius (rw) of reaction points (sum of rw of bromine and hydrogen atoms 3.05 A).

The effect of boronic ester substitution on the room-temperature phosphorescence properties of phenoxathiine-based derivatives was thoroughly investigated. A significantly improved phosphorescence quantum efficiency of up to 20% in the crystalline state was achieved by delicate molecular manipulation for both enhanced spin-orbital coupling and compact intermolecular packing.

Solution-processed lead halide perovskite quantum dots (QDs) are emerging as one of the most promising candidates for emissive display application. Although perovskite QDs with a full spectrum of visible light emissions have been realized for years, realizing the efficient electroluminescence of blue perovskites at room temperature still faces severe challenges. Herein, we demonstrate both the efficient photoluminescence and electroluminescence of the blue perovskite QDs via a simple FABr-modified multi-cation hot-injection (FMMHI) method. The FMMHI method is unique in both the addition of FABr into the PbBr2 precursor solution and the incorporation of small rubidium (Rb+) into the blue perovskite QDs light-emitting diodes (QLEDs). The addition of FABr into the precursor solution can realize strong quantum confinement effect, large exciton binding energy and high-quality perovskite QD films. Besides, the bandgap can be enlarged by the Rb+-induced perovskite octahedral distortion and strong quantum confinement effect. Excellent PLQYs of 64.5% and 49.8% were achieved for the developed greenish-blue QDs (Rb0.33Cs0.67)0.42FA0.58PbBr3 and deep-blue QDs (Rb0.33Cs0.67)0.42FA0.58PbCl1.25Br1.75 in solid film state. Moreover, maximum external quantum efficiencies (EQEs) of 3.6% and 0.61% were also achieved with an electroluminescence peak wavelength at 502 and 466 nm, respectively, indicating that the perovskite QDs incorporated with Rb+ possess great potential for the development of high-performance blue perovskite electroluminescence diodes.

A severe efficiency roll-off at high luminance in organic light-emitting diodes (OLEDs) generally results from a long exciton lifetime or an inappropriate device structure. The design strategy of the device plays a central role in realizing the inherent maximum potential of a specific emitter with an intrinsic photoluminescence quantum yield (PLQY) in an OLED via facilitating carrier injection, transport, and exciton confinement for efficient light emission. In this work, a yellow thermally activated delayed fluorescence (TADF) emitter, tri-PXZ-TRZ with a high PLQY and a short exciton lifetime is systematically investigated for its utilization in OLEDs. Judicious selection of suitable materials with higher energy offsets for the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and triplet excitons as well as balanced carrier injection led to the realization of highly efficient OLEDs. The maximum external quantum efficiency (EQE) of the fabricated OLEDs with tri-PXZ-TRZ as the emitter is improved from 13.3% to 21.0% via rational device engineering. Upon achieving an effective balance between the efficiency and the corresponding roll-off, the EQE was found to be retained at >10% even at a super high luminance of 60 000 cd m−2. Our results demonstrate that TADF emitter based OLEDs with well-designed device configurations could be promising for future low-cost and large-scale applications at high luminance.

Many companies have applied virtual reality (VR), a new and popular technology, to their corporate social responsibility (CSR) activities. This study examines how 360-degree VR-powered videos might further enhance consumers’ engagement in CSR activities and facilitate business outcomes during a crisis setting. The researchers conducted an online survey study, during the coronavirus (COVID-19) pandemic, with 1422 representative U.S. residents and applied the structural equation modeling for data analysis. Results indicated that the four categories of gratifications-sought (i.e., being there, enhancement, interaction, and fun) on 360-degree VR-powered videos could all positively influence CSR engagement; in contrast, CSR skepticism would reduce such engagement online. Corporate social responsibility engagement further improved the organization-public relationships (OPRs) and ultimately influenced consumers’ word-of-mouth toward the company. Theoretical and practical implications of these findings were discussed.

Strategies for developing purely organic materials exhibiting both high efficiency and persistent room-temperature phosphorescence (RTP) have remained ambiguous and challenging. Herein, we propose that introducing an intermediate charge transfer (CT) state into the donor-acceptor binary molecular system holds promise for accomplishing this goal. Guest materials showing gradient ionization potentials were selected to fine-tune the intermolecularly formed CT state when doped into the same host material with a large electron affiliation potential. Such a CT intermediate state accelerates the population of the triplet exciton to benefit phosphorescent emission and decreases the phosphorescence lifetime via quenching the long-lived triplet excitons. As a result, a "trade-off" between a long phosphorescence lifetime (595 ms) and a high phosphorescent quantum yield (27.5%) can be obtained by tuning the host-guest energy gap offset. This finding highlights the key role of CT in RTP emission and provides new guidance for developing novel RTP systems.

Manganese-based Metal-organic Frameworks (Mn-MOFs) represents a unique sub-class of MOFs with low toxicity, oxidative ability, and biocompatibility, which plays vital role in the application of this class of MOFs in medical field. Mn-MOFs show great potential in biomedical applications, and has been extensively studied as compared to other MOFs in transition metal series. They are important in medical applications because Mn(II) possess large electron spin number and longer electron relaxation time. They display fast water exchange rate and could be employed as a potential MRI contrast agent because of their strong targeting ability. Manganese complexes with different ligands also display prospective applications in area such as carrier for drug targeting in anti-tumor and antimicrobial therapy. In the review presented herewith, the application of Mn-based complexes and Mn-MOFs have been emphasized in the area such as imaging viz. MRI, multimodal imaging, antitumor activities such as chemodynamic therapy, photodynamic therapy, sonodynamic therapy and antimicrobial applications. Also, how rational designing and syntheses of targeted Mn-based complexes and Mn-MOFs can engender desired applications.

Echinochloa crus-galli L., a notorious weed in rice paddy fields, is usually kept under control by mefenacet application at the pre-emergence or early post-emergence stage. Due to continuous and repeated usage, E. crus-galli is developing resistance to mefenacet in China. Two putative resistant and one susceptible E. crus-galli populations were collected from paddy fields in Jiangsu Province to characterize their herbicide resistance. Compared with the susceptible population, the two mefenacet-resistant populations had 2.8- and 4.1-times greater pre-emergence resistance, and 10- and 6.8-times greater early post-emergence resistance to mefenacet. These mefenacet-resistant E. crus-galli populations also exhibited cross- or multiple-resistance to acetochlor, pyraclonil, imazamox, and quinclorac. However, when the glutathione S-transferase (GST) inhibitor 4-chloro-7-nitrobenzoxadiazole (NBD-Cl) was applied prior to post-emergence treatment, mefenacet resistance levels were reduced in both populations. Additionally, GST activity in vivo in one resistant population was much higher than the susceptible population after mefenacet application. The very long chain fatty acid elongases (VLCFAEs) from both mefenacet-resistant populations required much higher mefenacet concentration to inhibit their activity. The reduced sensitivity of VLCFAEs to mefenacet indicates the presence of a target-site resistance mechanism and induction of high GST activity may provide additional contribution to E. crus-galli mefenacet resistance through a non-target-site mechanism.

The fact about the blackjack is that the dealer gains advantages all the time in the normal casino since the rules can be changed by the casino. The way they change rules affects the probabilities of winning for both players and dealers. Therefore, it is important for the players to learn how could the house edge occur and the strategy to maximize their advantages individually. The theoretical analysis and simulations of the experiment by computer programs, for the sake of data, are the tools for solving the problems mentioned in this paper. The house edge is resulted by difference of the bet and the probability of winning the game, and the basic strategy created slightly advantages for the players in the case that house edge always exists.

Enhancing the rate of reverse intersystem crossing (krisc) and the rate of radiative transition (kr) has been regarded as the key to improve molecular design strategy in the field of thermally activated delayed fluorescence (TADF) materials. Herein, two sky-blue donor–acceptor (D–A)-type TADF materials, namely, CzDCNPy and tBuCzDCNPy, were designed following a strategy of controlling the energy difference among the charge-transfer singlet state (1CT), local exciton triplet state (3LE), and charge-transfer triplet state (3CT). Significantly different from most previously reported TADF materials, large values of kr and krisc and a nearly 100% exciton utilization efficiency were simultaneously achieved despite nonobvious delayed fluorescence and a large value of the singlet–triplet energy difference (ΔEST) being observed. This work presents a view that photoinduced delayed fluorescence and a small ΔEST are sufficient but not necessary for TADF materials. It also provides a reference that the high-energy 3LE ...

An organic compound exhibiting simultaneously reversible switch between its emission colors and luminescence mechanisms, possessing high contrast from deep blue normal fluorescence (NF) to yellow thermally activated delayed fluorescence (TADF), is reported. Based on these two complementary colors, white-light emission combining NF and TADF from a single compound can be achieved in various states. Experimental results and density functional theory calculations indicate that the controllable conformational distribution under thermal and mechanical activation is the mechanism responsible for the reversible switching behavior.

The design of orange-light emitting, thermally activated, delayed fluorescence (TADF) materials is necessary and important for the development and application of organic light-emitting diodes (OLEDs). Herein, two donor–acceptor–donor (D–A–D)-type orange TADF materials based on fluorenone and acridine, namely 2,7-bis(9,9-dimethylacridin-10(9H)-yl)-9H-fluoren-9-one (27DACRFT, 1) and 3,6-bis(9,9-dimethylacridin-10(9H)-yl)-9H-fluoren-9-one (36DACRFT, 2), were successfully synthetized and characterized. The studies on their structure–property relationship show that the different configurations have a serious effect on the photoluminescence and electroluminescence performance according to the change in singlet–triplet splitting energy (ΔEST) and excited state geometry. This indicates that a better configuration design can reduce internal conversion and improve triplet exciton utilization of TADF materials. Importantly, OLEDs based on 2 exhibited a maximum external quantum efficiency of 8.9%, which is higher than the theoretical efficiency of the OLEDs based on conventional fluorescent materials.

With the advantages of facile one-pot synthesis and THF-irrigating purification, we first developed novel cyclic compounds with deep blue thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP) dual emission even in the as-spun films. Careful crystal analysis, combined with theoretical calculations, reveal that abundant inter- and intra-molecular interactions, whatsoever the molecular packing, are obligated to unique RTP properties. These results open up a new study of compounds with multiple acceptors and donors, and represent an important step in the further development of deep blue TADF and easy RTP emission.