The methyltransferase like 3 （METTL3）-containing methyltransferase complex catalyzes the N6-methyladenosine （m6A） formation, a novel epitranscriptomic marker; however, the nature of this complex ...remains largely unknown. Here we report two new components of the human m6A methyltransferase complex, Wilms＇ tumor 1-associating protein （WTAP） and methyltransferase like 14 （METTL14）. WTAP interacts with METTL3 and METTL14, and is required for their localization into nuclear speckles enriched with pre-mRNA processing factors and for catalytic ac- tivity of the m6A methyltransferase in vivo. The majority of RNAs bound by WTAP and METTL3 in vivo represent mRNAs containing the consensus m6A motif. In the absence of WTAP, the RNA-binding capability of METTL3 is strongly reduced, suggesting that WTAP may function to regulate recruitment of the m6A methyltransferase complex to mRNA targets. Furthermore, transcriptomic analyses in combination with photoactivatable-ribonucleoside-en- hanced crosslinking and immunoprecipitation （PAR-CLIP） illustrate that WTAP and METTL3 regulate expression and alternative splicing of genes involved in transcription and RNA processing. Morpholino-mediated knockdown targeting WTAP and/or METTL3 in zebrafish embryos caused tissue differentiation defects and increased apoptosis. These findings provide strong evidence that WTAP may function as a regulatory subunit in the m6A methyltransferase complex and play a critical role in epitranscriptomic regulation of RNA metabolism.
Developing red thermally activated delayed fluorescence (TADF) emitters for high‐performance OLEDs is still facing great challenge. Herein, three red TADF emitters, pDBBPZ‐DPXZ, pDTBPZ‐DPXZ, and ...oDTBPZ‐DPXZ, are designed and synthesized with same donor–acceptor (D‐A) backbone with different peripheral groups attaching on the A moieties. Their lowest triplet states change from locally excited to charge transfer character leading to significantly enhance reverse intersystem crossing process. In particular, oDTBPZ‐DPXZ exhibits efficient TADF feature and exciton utilization. It not only achieves an external quantum efficiency (EQE) of 20.1 % in red vacuum‐processed OLED, but also realize a high EQE of 18.5 % in a solution‐processed OLED, which is among the best results in solution‐processed red TADF OLEDs. This work provides an effective strategy for designing red TADF molecules by managing energy level alignments to facilitate the up‐conversion process and thus enhance exciton harvesting.
By introducing phenyl or o‐tolyl groups into different positions of the same acceptor backbone, the lowest triplet energy levels of red thermally activated delayed fluorescence emitters can be tuned from locally excited triplet (3LEA) to charge transfer triplet (3CT) states, resulting in enhancement of the rates of reverse intersystem crossing (RISC), and boosting efficiencies in both vacuum‐ and solution‐processed OLEDs.
In the presence of Pd(PPh3)4 (2.5 mol%), PPh3 (10 mol%) and pyridine (2.0 equiv.), the formal 5+3 cycloaddition of vinylethylene carbonates with isatin‐based α‐(trifluoromethyl)imines proceeded ...readily, and delivered trans‐configured novelmedium‐heterocycle‐fused spirooxindoles in 75–97% chemical yields with excellent diastereoselectivities. The relative stereochemical configuration of the title products was identified by X‐ray diffraction analysis.
Multiple resonance (MR) type thermally activated delayed fluorescence (TADF) material is currently a research hotspot in organic light‐emitting diodes (OLEDs) due to their high color purity and high ...exciton utilization. However, there are only a handful of MR‐TADF emitters with emissions beyond the blue‐to‐green region. The very limited emission colors for MR‐TADF emitters are mainly caused by the fact that so far molecular modifications of MR‐TADF do not offer much change in the emission colors. Here, we report a new approach to modifying a prototypical MR core of DABNA by fusing carbazoles to the MR framework. The carbazole‐fused molecule (TCZ‐F‐DABNA) basically maintains the MR‐dominated features of DABNA while red‐shifting the emission. Its OLED achieves an external quantum efficiency of 39.2 % with a peak at 588 nm, which is a record‐high efficiency for OLEDs with peaks beyond 560 nm. This work provides a new approach for significantly tunning emission colors of MR‐TADF emitters.
A new approach is reported by fusing carbazoles to a MR framework DABNA to significantly redshift emission while maintaining the MR‐dominated features. The carbazole‐fused molecule TCZ‐F‐DABNA can deliver a high PLQY of 99 %. Its OLEDs reached a record‐high EQE of 39.2 %.
Xiyanping (XYP) is a Chinese herbal medicine used in the clinic to treat respiratory infection and pneumonia. Recent evidence identified XYP as a potential inhibitor of severe acute respiratory ...syndrome coronavirus 2, implying XYP as a possible treatment for the coronavirus disease 2019 (COVID‐19). Here, we conducted a prospective, multicenter, open‐label and randomized controlled trial to evaluate the safety and effectiveness of XYP injection in patients with mild to moderate COVID‐19. We consecutively recruited 130 COVID‐19 patients with mild to moderate symptoms from five study sites, and randomized them in 1:1 ratio to receive XYP injection in combination with standard therapy or receive standard supportive therapy alone. We found that XYP injection significantly reduced the time to cough relief, fever resolution and virus clearance. Less patients receiving XYP injection experienced disease progression to the severe stage during the treatment process. No severe adverse events were reported during the study. Taken together, XYP injection is safe and effective in improving the recovery of patients with mild to moderate COVID‐19. However, further studies are warranted to evaluate the efficacy of XYP in an expanded cohort comprising COVID‐19 patients at different disease stages.
Bridging the theory of affective labor and reproductive labor, this paper proposes “affective reproduction” as a critical framework to analyze the unpaid work of volunteer content moderation. ...Findings from this study problematize the one-sided focus on streamers in the extant literature on platform labor vis-à-vis live-streaming. It contends that fan moderators help streamers reproduce the live-streaming atmosphere as friendly, pleasant, and relevant, facilitating Internet celebrities’ money-making. This study contributes to studies of digital labor in two ways: 1) it expands the labor and work perspective to the study of content moderation and discloses the indirect value-generating nature of this work; 2) the designation of moderator in Chinese live-streaming platforms reveals a new form of work organization that exploits digital intimacy, transforming platform users into non-professional, secondary cultural workers. The proposed framework is applicable to various forms of participatory media, in which users are encouraged to manage and regulate their peers.
In the presence of PhCO2H (20 mol%), the formal 3+2 cycloaddition between in situ formed 1,4‐benzodiazepin‐2‐one‐based azomethine ylides and azodicarboxylic acid derivatives proceeded readily, thus ...leading to the formation of trans‐configured spiro‐1,4‐benzodiazepin‐2‐ones in up to 98% chemical yield with >20:1 dr. The relative configuration of the title compounds was unambiguously determined by means of X‐ray single crystal structure analysis. The reaction mechanism was hypothesized to account for the diastereoselective formation of the isolated spiro‐1,4‐benzodiazepin‐2‐ones.
We reported the selective electrochemical reduction of oxygen (O2) to hydroxyl radicals (.OH) via 3‐electron pathway with FeCo alloy encapsulated by carbon aerogel (FeCoC). The graphite shell with ...exposed ‐COOH is conducive to the 2‐electron reduction pathway for H2O2 generation stepped by 1‐electron reduction towards to .OH. The electrocatalytic activity can be regulated by tuning the local electronic environment of carbon shell with the electrons coming from the inner FeCo alloy. The new strategy of .OH generation from electrocatalytic reduction O2 overcomes the rate‐limiting step over electron transfer initiated by reduction‐/oxidation‐state cycle in Fenton process. Fast and complete removal of ciprofloxacin was achieved within 5 min in this proposed system, the apparent rate constant (kobs) was up to 1.44±0.04 min−1, which is comparable with the state‐of‐the‐art advanced oxidation processes. The degradation rate almost remains the same after 50 successive runs, suggesting the satisfactory stability for practical applications.
Hydroxyl radicals are efficiently and continuously generated from selective electrochemical O2 reduction via 3‐electron pathway with FeCoC electrode, overcoming the rate‐limiting step of electron transfer initiated by reduction‐/oxidation‐state cycle. Fast and complete removal of organics with the apparent rate constant of 1.44±0.04 min−1 represents high potential for practical water purification.
While monochrome organic light‐emitting diodes (OLEDs) based on thermally activated delayed fluorescence (TADF) emitters have achieved over 30% external quantum efficiencies (EQEs), all‐TADF white ...OLEDs (WOLEDs) are still lagging behind. Herein, a simple system based on two color‐complementary TADF emitters is exploited to realize high‐performance WOLEDs. By doping a high‐performance orange–red TADF fluorophor (BPPZ‐DPXZ) into a blue TADF host (DBFCz‐Trz), energy transfer, and triplet‐to‐singlet conversion in the host‐dopant system can be optimized to simultaneously achieve full exciton utilization and color balance. With this design, all‐TADF single‐emitting‐layer WOLEDs with a maximum EQE up to 32.8% are demonstrated. This high efficiency surpasses EQEs of reported WOLEDs based on both TADF as well as phosphorescence. It is expected that this finding can provide new insight for designing highly efficient all‐TADF WOLEDs.
All thermally activated delayed fluorescence (TADF) single‐emitting‐layer white organic light‐emitting diodes are developed by using a high‐efficiency orange–red TADF fluorophor doped in a blue TADF fluorophor. Singlet and triplet excitons in the devices can be well shared and captured in two emitters, resulting in state‐of‐the‐art performances with maximum external quantum efficiencies of over 30%.
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![Formal [5+3] Cycloaddition ...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1615-4150/small "Formal [5+3] Cycloaddition of Vinylethylene Carbonates with Isatin‐Based α‐(Trifluoromethyl)imines for Diastereoselective Synthesis of Medium‐Heterocycle‐Fused Spirooxindoles")
