Benzoxaboroles are effective against bacterial, fungal and protozoan pathogens. We report potent activity of the benzoxaborole AN3661 against Plasmodium falciparum laboratory-adapted strains (mean IC50 32 nM), Ugandan field isolates (mean ex vivo IC50 64 nM), and murine P. berghei and P. falciparum infections (day 4 ED90 0.34 and 0.57 mg kg−1, respectively). Multiple P. falciparum lines selected in vitro for resistance to AN3661 harboured point mutations in pfcpsf3, which encodes a homologue of mammalian cleavage and polyadenylation specificity factor subunit 3 (CPSF-73 or CPSF3). CRISPR-Cas9-mediated introduction of pfcpsf3 mutations into parental lines recapitulated AN3661 resistance. PfCPSF3 homology models placed these mutations in the active site, where AN3661 is predicted to bind. Transcripts for three trophozoite-expressed genes were lost in AN3661-treated trophozoites, which was not observed in parasites selected or engineered for AN3661 resistance. Our results identify the pre-mRNA processing factor PfCPSF3 as a promising antimalarial drug target.

Quantum-dot light-emitting diodes (QLEDs) may combine superior properties of colloidal quantum dots (QDs) and advantages of solution-based fabrication techniques to realize high-performance, large-area, and low-cost electroluminescence devices. In the state-of-the-art red QLED, an ultrathin insulating layer inserted between the QD layer and the oxide electron-transporting layer (ETL) is crucial for both optimizing charge balance and preserving the QDs' emissive properties. However, this key insulating layer demands very accurate and precise control over thicknesses at sub-10 nm level, causing substantial difficulties for industrial production. Here, it is reported that interfacial exciton quenching and charge balance can be independently controlled and optimized, leading to devices with efficiency and lifetime comparable to those of state-of-the-art devices. Suppressing exciton quenching at the ETL-QD interface, which is identified as being obligatory for high-performance devices, is achieved by adopting Zn Mg O nanocrystals, instead of ZnO nanocrystals, as ETLs. Optimizing charge balance is readily addressed by other device engineering approaches, such as controlling the oxide ETL/cathode interface and adjusting the thickness of the oxide ETL. These findings are extended to fabrication of high-efficiency green QLEDs without ultrathin insulating layers. The work may rationalize the design and fabrication of high-performance QLEDs without ultrathin insulating layers, representing a step forward to large-scale production and commercialization.

a b s t r a c tWe have used boron-based molecules to create novel, competitive, reversible inhibitors of phosphodiesterase 4 (PDE4). The co-crystal structure reveals a binding configuration which is unique compared to classical catechol PDE4 inhibitors, with boron binding to the activated water in the bimetal center. These phenoxybenzoxaboroles can be optimized to generate submicromolar potency enzyme inhibitors, which inhibit TNF-a, IL-2, IFN-c, IL-5 and IL-10 activities in vitro and show safety and efficacy for topical treatment of human psoriasis. They provide a valuable new route for creating novel potent anti-PDE4 inhibitors.

Poor solubility often leads to low drug efficacy. Encapsulation of water‐insoluble drugs in polymeric nanoparticles offers a solution. However, low drug loading remains a critical challenge. Now, a simple and robust sequential nanoprecipitation technology is used to produce stable drug‐core polymer‐shell nanoparticles with high drug loading (up to 58.5 %) from a wide range of polymers and drugs. This technology is based on tuning the precipitation time of drugs and polymers using a solvent system comprising multiple organic solvents, which allows the formation of drug nanoparticles first followed by immediate precipitation of one or two polymers. This technology offers a new strategy to manufacture polymeric nanoparticles with high drug loading having good long‐term stability and programmed release and opens a unique opportunity for drug delivery applications.

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Inorganic−organic hybrid perovskites have drawn considerable attention in photovoltaics and light-emitting diodes (LEDs) due to their exceptional optoelectronic properties. Perovskite multiple quantum wells (MQWs), which employ large organic ammonium cations to form layered structures, have been developed for high-efficiency perovksite LEDs (PeLEDs). However, little is known about the impacts of large organic ammonium cations on the properties of MQW films. In this work, we report MQW perovskites of phenylbutylammonium-cesium lead iodides, which exhibit a photoluminescence peak at 664 nm with a quantum efficiency of 58%. These perovskite MQW films enable red LEDs with high external quantum efficiencies (EQEs) of up to 13.3%. Furthermore, we deposit MQW perovskites of butylammonium-cesium lead iodides. The comparisons of the two perovskite MQW films demonstrate that the choices of large organic ammonium cations significantly influence the properties of the perovskite MQW films, that is, distributions of the quantum-well thicknesses, energy transfer processes, and recombination channels of the emissive centers. Our study shall shed light on the rational design of highperformance perovskite MQW films toward their potential application as red light sources.

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Most of the biomedical materials printed using 3D bioprinting are static and are unable to alter/transform with dynamic changes in the internal environment of the body. The emergence of four-dimensional (4D) printing addresses this problem. By preprogramming dynamic polymer materials and their nanocomposites, 4D printing is able to produce the desired shapes or transform functions under specific conditions or stimuli to better adapt to the surrounding environment. In this review, the current and potential applications of 4D-printed materials are introduced in different aspects of the biomedical field, e.g., tissue engineering, drug delivery, and sensors. In addition, the existing limitations and possible solutions are discussed. Finally, the current limitations of 4D-printed materials along with their future perspective are presented to provide a basis for future research.