A record-high EQE of 7.65%@3300 cd m-2 achieved in non-doped near-ultraviolet OLEDs based on novel D'-D-A type bipolar fluorophores upon molecular configuration engineering.

Developing a high-performance near-ultraviolet (NUV) material and its simple non-doped device with a small efficiency roll-off and good color purity is a promising but challenging task. Here, we proposed a novel donor'-donor-acceptor (D'-D-A) type molecular strategy to largely solve the intrinsic contradictions among wide-bandgap NUV emission, fluorescence efficiency, carrier injection and transport. An efficient NUV fluorophore, 3,6-mPPICNC3, exhibiting a hybridized local and charge-transfer state, is achieved through precise molecular configuration engineering, realizing similar hole and electron mobilities at both low and high electric fields. Moreover, the planarized intramolecular charge transfer excited state and steric hindrance effect endow 3,6-mPPICNC3 with a considerable luminous efficiency and good color purity in the aggregation state. Consequently, the non-doped device emitting stable NUV light with Commission Internationale de l'Eclairage (CIE) coordinates of (0.160, 0.032) and a narrow full width at half maximum of 44 nm exhibits a state-of-the-art external quantum efficiency (EQE) of 7.67% and negligible efficiency roll-off over a luminance range from 0 to 3300 cd m-2. This is a record-high efficiency among all the reported non-doped NUV devices. Amazingly, an EQE of 7.85% and CIE coordinates of (0.161, 0.025) are achieved in the doped device. This demonstrates that the D'-D-A-type molecular structure has great potential for developing high-performance organic light-emitting materials and their optoelectronic applications.

Combined effects of climate and land-use changes on the alpha and beta functional diversities of terrestrial mammals in China.

Climate and land-use changes are predicted to impact biodiversity, threatening ecosystem services and functions. However, their combined effects on the functional diversity of mammals at the regional scale remain unclear, especially at the beta level. Here, we use projected climate and land-use changes in China to investigate their potential effects on the alpha and beta functional diversities of terrestrial mammals under low- and high-emission scenarios. In the current projection, we showed strong positive spatial correlations between functional richness and species richness. Functional evenness (FEve), functional specialization (FSpe), and functional originality (FOri) decreased with species richness, and functional divergence (FDiv) increased first and then plateaued. Functional beta diversity was dominated by its nestedness component, in contrast to the taxonomic facet. Potential changes in species richness are more strongly influenced by land-use change under the low-emission scenario, while under the high-emission scenario, they are more strongly influenced by climate change. Changes in functional richness (FRic) were inconsistent with those in species richness, with a magnitude of decreases greater than predicted from species richness. Moreover, mammal assemblages showed potential functional differentiation (FD) across the country, and the trends exceeded those towards taxonomic differentiation (TD). Our findings help us understand the processes underlying biodiversity responses to global changes on multiple facets and provide new insight for conservation plans.

Licocoumarone induces BxPC-3 pancreatic adenocarcinoma cell death by inhibiting DYRK1A.

Protein kinases play an indispensable role in signaling pathways that regulate tumor cell functions, which represent potent therapeutic targets in cancers. Dual-specificity tyrosine phosphorylation regulated kinase 1A (DYRK1A) as a serine/threonine kinase has recently been reported to be upregulated in pancreatic ductal adenocarcinoma (PDAC) and show protumorigenic effect. By activity-guided phytochemical investigation of the extracts from Glycyrrhiza uralensis Fisch, we expect to find the effective constituents that can suppress pancreatic cancer cell proliferation and/or induce cells apoptotic by inhibiting DYRK1A. Eight isopentenyl-substituted compounds (1-8), including four coumarins (1-4), one benzofuran (5), and three flavonoids (6-8), were isolated and identified from G. uralensis Fisch. Among them, licocoumarone (LC, 5) showed effective inhibitory activity against DYRK1A with an IC50 value of 12.56 µM. Molecular docking analysis suggested that LC completely occupied the whole pocket of DYRK1A and formed obvious hydrophobic interactions and hydrogen bonds with DYRK1A residues. Further in vitro validation, including Microscale Thermophoresis (MST) and drug affinity responsive target stability (DARTS) techniques, demonstrated the specific combining capacity of LC to DYRK1A. Meanwhile, LC induced significant cytotoxicity against DYRK1A-overexpressing BxPC-3 cells with an IC50 value of 50.77 µM. Mechanism studies revealed that LC reduced c-MET protein level by inhibiting DYRK1A. These findings provide preliminary evidences that LC as a natural DYRK1A inhibitor suppresses human pancreatic adenocarcinoma BxPC-3 cell proliferation and induces cell apoptotic, which might present new options and possibilities for targeted therapies in pancreatic cancer therapy.