An outbreak of coronavirus disease 2019 (COVID-19) 1-3 , caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 4 , has spread globally. Countermeasures are needed to treat and prevent further dissemination of the virus. Here we report the isolation of two specific human monoclonal antibodies (termed CA1 and CB6) from a patient convalescing from COVID-19. CA1 and CB6 demonstrated potent SARS-CoV-2-specific neutralization activity in vitro. In addition, CB6 inhibited infection with SARS-CoV-2 in rhesus monkeys in both prophylactic and treatment settings. We also performed structural studies, which revealed that CB6 recognizes an epitope that overlaps with angiotensin-converting enzyme 2 (ACE2)-binding sites in the SARS-CoV-2 receptor-binding domain, and thereby interferes with virus-receptor interactions by both steric hindrance and direct competition for interface residues. Our results suggest that CB6 deserves further study as a candidate for translation to the clinic.

High-performance thin-film electrochemical energy storage devices from metal oxide-based nanostructure arrays will be presented, which include flexible/solid-state supercapacitors and Li ion batteries as well as supercapacitor-battery hybrid systems. As typical electrochemical energy storage devices, supercapacitors and lithium ion batteries have potential applications in a wide range of fields such as microelectronic devices, portable electronics, and large-scale electric vehicles, etc. In this talk, I will mainly discuss the electrochemical energy storage application of one kind of emerging electrode architecture, that is, metal oxide-based nanostructure arrays grown directly on current collector substrates [1]. The direct growth of nanostructures on current collector represents a popular way to fabricate thin-film electrodes, which not only ensures good charge transport, but also provides sufficient structural interspaces for buffering volume expansion of the electrode materials. When combined with using flexible current collector, such thin-film electrode also has greater durability to shape deformation, giving better mechanical flexibility. By pairing appropriate electrode materials, ordered core-shell and hierarchical hybrid nanostructures can be rationally designed, which leads to synergistic improvement in terms of electrical/ionic conductivity, electrochemical stability and structural integration [2]. Hybrid electrode materials with high capacitance/capacity, long cycle life and exceptional rate capability can thus be obtained; the related performance enhancement mechanism will also be discussed in detail. In the end, I will further show that these binder-free nanoarray electrodes have enabled high-performance thin-film/flexible/solid-state supercapacitors and Li ion batteries as well as supercapacitor-battery hybrid systems [3-5].

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Bisphenols (BPs), which have more than ten kinds of structural analogues, are emerging as the most important endocrine disrupting chemicals that adversely affect human health and aquatic life. A tyrosinase nanosensor based on metal-organic frameworks (MOFs) and chitosan was developed to investigate the electrochemical response characteristics and mechanisms of nine kinds of BPs for the first time. The developed tyrosinase nanosensor showed a sensitive response to bisphenol A, bisphenol F, bisphenol E, bisphenol B, and bisphenol Z, and the responsive sensitivities were highly dependent on their respective log Kow values. However, the nanosensor showed no response to bisphenol S (BPS), bisphenol AP (BPAP), bisphenol AF (BPAF), or tetrabromobisphenol A, although BPS, BPAP, and BPAF have structures similar to those of the responsive BPs. The obtained results reveal that the electrochemical response of different BPs is affected not only by the molecular structure, especially the available ortho positions of phenolic hydroxyl groups, but also by the substituent group properties (electron acceptor or electron donor) on the bisphenol framework. The electronic cloud distribution of the phenolic hydroxyl groups, which is affected by the substituent group, determines whether the available ortho positions of phenolic hydroxyl groups can be oxidized by the tyrosinase biosensor. These response mechanisms are very significant as they can be used for predicting the response characteristics of many BPs and their various derivatives and metabolites on biosensors. The unexpected anti-interference ability of the biosensor to nine heavy metal ions was also discovered and discussed. The MOF-chitosan nanocomposite proves to be a promising sensing platform for the construction of diverse biosensors for selective detection of targets even in the presence of a high concentration of heavy metal ions.

Wire‐shaped asymmetric pseudocapacitors with both pseudocapacitive cathode and anode are promising in facilitating device assembly and provide highly efficient power sources for wearable electronics. However, it is a great challenge to simultaneously obtain high energy and power as well as ultralong cycling life for practical demands of such devices. Herein, a device design with new cathode/anode coupling is proposed to achieve excellent comprehensive performance in a wire‐type quasi‐solid‐state asymmetric pseudocapacitor (WQAP). The hierarchical α‐MnO 2 nanorod@δ‐MnO 2 nanosheet array cathode and MoO 2 @C nanofilm anode are directly grown on flexible tiny Ti wires by well‐established hydrothermal and electrodeposition techniques, which ensures rapid charge/mass transport kinetics and the sufficient utilization of pseudocapacitance. The nanoarray/film electrode also facilitates integration with gel electrolyte of polyvinyl alcohol–LiCl, guaranteeing the durability. The resulting WQAP with 2.0 V voltage delivers high volumetric energy and power densities (9.53 mWh cm −3 and 22720 mW cm −3 , respectively) as well as outstanding cycling stability over 100 000 times, surpassing all the previously reported WQAPs. In addition, the device can be facilely connected in parallel or in series with minimal internal resistance, and be fabricated at the 1 m scale with excellent flexibility. This work opens the way to develop high‐performance integrated wire supercapacitors.

Prokaryotes possess CRISPR-Cas systems to exclude parasitic predators, such as phages and mobile genetic elements (MGEs). These predators, in turn, encode anti-CRISPR (Acr) proteins to evade the CRISPR-Cas immunity. Recently, AcrVA4, an Acr protein inhibiting the CRISPR-Cas12a system, was shown to diminish Lachnospiraceae bacterium Cas12a (LbCas12a)-mediated genome editing in human cells, but the underlying mechanisms remain elusive. Here we report the cryo-EM structures of AcrVA4 bound to CRISPR RNA (crRNA)-loaded LbCas12a and found AcrVA4 could inhibit LbCas12a at several stages of the CRISPR-Cas working pathway, different from other characterized type I/II Acr inhibitors which target only 1 stage. First, it locks the conformation of the LbCas12a-crRNA complex to prevent target DNA-crRNA hybridization. Second, it interacts with the LbCas12a-crRNA-dsDNA complex to release the bound DNA before cleavage. Third, AcrVA4 binds the postcleavage LbCas12a complex to possibly block enzyme recycling. These findings highlight the multifunctionality of AcrVA4 and provide clues for developing regulatory genome-editing tools.