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Manipulating liquids with tunable shape and optical functionalities in real time is important for electroactive flow devices and optoelectronic devices, but remains a great challenge. Here, we demonstrate electrotunable liquid sulfur microdroplets in an electrochemical cell. We observe electrowetting and merging of sulfur droplets under different potentiostatic conditions, and successfully control these processes via selective design of sulfiphilic/sulfiphobic substrates. Moreover, we employ the electrowetting phenomena to create a microlens based on the liquid sulfur microdroplets and tune its characteristics in real time through changing the shape of the liquid microdroplets in a fast, repeatable, and controlled manner. These studies demonstrate a powerful in situ optical battery platform for unraveling the complex reaction mechanism of sulfur chemistries and for exploring the rich material properties of the liquid sulfur, which shed light on the applications of liquid sulfur droplets in devices such as microlenses, and potentially other electrotunable and optoelectronic devices., Manipulating liquids with tunable shape and optical functionalities in real time remains a great challenge. Here, the authors demonstrate electrotunable liquid sulfur microdroplets in an electrochemical cell and tune its characteristics in a fast, repeatable, and controlled manner.

Cross-coupling reactions have developed into powerful approaches for carbon–carbon bond formation. In this work, a Ni-catalyzed migratory Suzuki–Miyaura cross-coupling featuring high benzylic or allylic selectivity has been developed. With this method, unactivated alkyl electrophiles and aryl or vinyl boronic acids can be efficiently transferred to diarylalkane or allylbenzene derivatives under mild conditions. Importantly, unactivated alkyl chlorides can also be successfully used as the coupling partners. To demonstrate the applicability of this method, we showcase that this strategy can serve as a platform for the synthesis of terminal, partially deuterium-labeled molecules from readily accessible starting materials. Experimental studies suggest that migratory cross-coupling products are generated from Ni(0/II) catalytic cycle. Theoretical calculations indicate that the chain-walking occurs at a neutral nickel complex rather than a cationic one. In addition, the original-site cross-coupling products can be obtained by alternating the ligand, wherein the formation of the products has been rationalized by a radical chain process., Migratory cross-coupling reactions are powerful tools to form bonds at predictable positions. Here the authors report a nickel-catalyzed migratory Suzuki–Miyaura cross-coupling of unactivated alkyl electrophiles with aryl and vinyl boron reagents and provide experimental and computational mechanistic evidence.

Accumulating mutations in the SARS-CoV-2 Spike (S) protein can increase the possibility of immune escape, challenging the present COVID-19 prophylaxis and clinical interventions. Here, 3 receptor binding domain (RBD) specific monoclonal antibodies (mAbs), 58G6, 510A5 and 13G9, with high neutralizing potency blocking authentic SARS-CoV-2 virus display remarkable efficacy against authentic B.1.351 virus. Surprisingly, structural analysis has revealed that 58G6 and 13G9 both recognize the steric region S470–495 on the RBD, overlapping the E484K mutation presented in B.1.351. Also, 58G6 directly binds to another region S450–458 in the RBD. Significantly, 58G6 and 510A5 both demonstrate prophylactic efficacy against authentic SARS-CoV-2 and B.1.351 viruses in the transgenic mice expressing human ACE2 (hACE2), protecting weight loss and reducing virus loads. Together, we have evidenced 2 potent neutralizing Abs with unique mechanism targeting authentic SARS-CoV-2 mutants, which can be promising candidates to fulfill the urgent needs for the prolonged COVID-19 pandemic., Neutralizing antibodies are currently one versatile strategy to treat SARS-CoV-2 infection. Here, Li et al. characterize three monoclonal antibodies neutralizing authentic virus infection in vitro and in vivo by targeting the receptor binding domain as evidenced by Cryo-EM.

Lithium intercalation of MoS

To increase the reliability and success rate of drug discovery, efforts have been made to increase the C(sp3) fraction and avoid flat molecules. sp3-Rich enantiopure amines are most frequently encountered as chiral auxiliaries, synthetic intermediates for pharmaceutical agents and bioactive natural products. Streamlined construction of chiral aliphatic amines has long been regarded as a paramount challenge. Mainstream approaches, including hydrogenation of enamines and imines, C–H amination, and alkylation of imines, were applied for the synthesis of chiral amines with circumscribed skeleton structures; typically, the chiral carbon centre was adjacent to an auxiliary aryl or ester group. Herein, we report a mild and general nickel-catalysed asymmetric reductive hydroalkylation to effectively convert enamides and enecarbamates into drug-like α-branched chiral amines and derivatives. This reaction involves the regio- and stereoselective hydrometallation of an enamide or enecarbamate to generate a catalytic amount of enantioenriched alkylnickel intermediate, followed by C–C bond formation via alkyl electrophiles., Enantiopure aliphatic amines are frequently encountered as chiral auxiliaries and synthetic intermediates for bioactive compounds. Here, the authors report a mild nickel-catalysed asymmetric reductive hydroalkylation to convert enamides and enecarbamates into α-branched chiral amines and derivatives.

Auger recombination is the main non-radiative decay pathway for multi-carrier states of colloidal quantum dots, which affects performance of most of their optical and optoelectronic applications. Outstanding single-exciton properties of CdSe/CdS core/shell quantum dots enable us to simultaneously study the two basic types of Auger recombination channels—negative trion and positive trion channels. Though Auger rates of positive trion are regarded to be much faster than that of negative trion for II-VI quantum dots in literature, our experiments find the two rates can be inverted for certain core/shell geometries. This is confirmed by theoretical calculations as a result of geometry-dependent dielectric screening. By varying the core/shell geometry, both types of Auger rates can be independently tuned for ~ 1 order of magnitude. Experimental and theoretical findings shed new light on designing quantum dots with necessary Auger recombination characteristics for high-power light-emitting-diodes, lasers, single-molecular tracking, super-resolution microscope, and advanced quantum light sources., Designing core/shell quantum dots with desired optoelectronic properties remains a challenge. Here, the authors investigate the negative and positive trions dynamics within a quantum dot, proposing an Auger engineering strategy based on geometry-dependent dielectrics for tuning optical properties.

Electric-field control of magnetism requires deterministic control of the magnetic order and understanding of the magnetoelectric coupling in multiferroics like BiFeO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Mitochondrial permeability transition pore (mPTP) is involved in cardiac dysfunction during chronic β-adrenergic receptor (β-AR) stimulation. The mechanism by which chronic β-AR stimulation leads to mPTP openings is elusive. Here, we show that chronic administration of isoproterenol (ISO) persistently increases the frequency of mPTP openings followed by mitochondrial damage and cardiac dysfunction. Mechanistically, this effect is mediated by phosphorylation of mitochondrial fission protein, dynamin-related protein 1 (Drp1), by Ca2+/calmodulin-dependent kinase II (CaMKII) at a serine 616 (S616) site. Mutating this phosphorylation site or inhibiting Drp1 activity blocks CaMKII- or ISO-induced mPTP opening and myocyte death in vitro and rescues heart hypertrophy in vivo. In human failing hearts, Drp1 phosphorylation at S616 is increased. These results uncover a pathway downstream of chronic β-AR stimulation that links CaMKII, Drp1 and mPTP to bridge cytosolic stress signal with mitochondrial dysfunction in the heart., β-adrenergic receptor signaling induces mitochondrial permeability transition pore (mPTP) opening. Here, Xu et al. show that this effect is mediated by phosphorylation of mitochondrial fission protein Drp1 by CamKII, which increases the frequency of transient mPTP opening.

Dysregulated inflammatory responses are known to impair wound healing in diabetes, but the underlying mechanisms are poorly understood. Here we show that the antimicrobial protein REG3A controls TLR3-mediated inflammation after skin injury. This control is mediated by REG3A-induced SHP-1 protein, and acts selectively on TLR3-activated JNK2. In diabetic mouse skin, hyperglycaemia inhibits the expression of IL-17-induced IL-33 via glucose glycation. The decrease in cutaneous IL-33 reduces REG3A expression in epidermal keratinocytes. The reduction in REG3A is associated with lower levels of SHP-1, which normally inhibits TLR3-induced JNK2 phosphorylation, thereby increasing inflammation in skin wounds. To our knowledge, these findings show for the first time that REG3A can modulate specific cutaneous inflammatory responses and that the decrease in cutaneous REG3A exacerbates inflammation in diabetic skin wounds., Patients with diabetes often have delayed wound healing, associated with excessive inflammation. Here the authors report that REG3A inhibits TLR3-driven inflammation in skin wounds, and show that REG3A is reduced in models of diabetes, which exacerbates inflammation in diabetic wounds.

Plasmon-generated hot carriers are used in photovoltaic or photochemical applications. However, the interplays between the plasmon and single-particle excitations in nanosystems have not been theoretically addressed using ab initio methods. Here we show such interplays in a Ag55 nanocluster using real-time time-dependent density functional theory simulations. We find that the disappearance of the zero-frequency peak in the Fourier transform of the band-to-band transition coefficient is a hallmark of the plasmon. We show the importance of the d-states for hot-carrier generations. If the single-particle d-to-s excitations are resonant to the plasmon frequency, the majority of the plasmon energy will be converted into hot carriers, and the overall hot-carrier generation is enhanced by the plasmon; if such resonance does not exist, we observe an intriguing Rabi oscillation between the plasmon and hot carriers. Phonons play a minor role in plasmonic dynamics in such small systems. This study provides guidance on improving plasmonic applications., Plasmons can enhance hot-carrier generation for efficient photochemical reactions, but the interplay between plasmons and single-particle excitations are difficult to capture in models. Here, the authors use real-time time-dependent density functional theory to study these interactions in silver nanocrystals.