Although electrochemical water splitting is an effective and green approach to produce oxygen and hydrogen, the realization of efficient bifunctional catalysts that are stable in variable ...electrolytes is still a significant challenge. Herein, we report a three-dimensional hierarchical assembly structure composed of an ultrathin Ru shell and a Ru-Ni alloy core as a catalyst functioning under universal pH conditions. Compared with the typical Ir/C-Pt/C system, superior catalytic performances and excellent durability of the overall water splitting under universal pH have been demonstrated. The introduction of Ni downshifts the d-band center of the Ru-Ni electrocatalysts, modulating the surface electronic environment. Density functional theory results reveal that the mutually restrictive d-band interaction lowers the binding of (Ru, Ni) and (H, O) for easier O-O and H-H formation. The structure-induced eg-dz2 misalignment leads to minimization of surface Coulomb repulsion to achieve a barrier-free water-splitting process.
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•A facile method for the synthesis of 3D hierarchical assembly Ru-Ni NA catalyst•Superior catalytic reactivity and stability of water splitting in universal pH•The introduction of Ni can modify the d-band and surface electronic environment•Minimization of the surface Coulomb repulsion leads to barrier-free catalysis process
Catalysis; Energy Materials; Materials Science
Two-dimensional (2D) materials such as graphene, transition metal dichalcogenides (TMDs), and their heterojunctions are prospective materials for future electronics, optoelectronics, and quantum ...technologies. Assembling different 2D layers offers unique ways to control optical, electrical, thermal, magnetic, and topological phenomena. Controlled fabrications of electronic grade 2D heterojunctions are of paramount importance. Here, we enlist novel and scalable strategies to fabricate 2D vertical and lateral heterojunctions, consisting of semiconductors, metals, and/or semimetals. Critical issues that need to be addressed are the device-to-device variations, reliability, stability, and performances of 2D heterostructures in electronic and optoelectronic applications. Also, stacking order-dependent formation of moiré excitons in 2D heterostructures are emerging with exotic physics and new opportunities. Furthermore, the realization of 2D heterojunction-based novel devices, including excitonic and valleytronic transistors, demands more extensive research efforts for real-world applications. We also outline emergent phenomena in 2D heterojunctions central to nanoelectronics, optoelectronics, spintronics, and energy applications.
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Ultrafast fiber lasers have gained rapid advances in last decades for their intrinsic merits such as potential of all-fiber format, excellent beam quality, superior power scalability, and high ...single-pass gain, which opened widespread applications in high-field science, laser machining, precision metrology, optical communication, microscopy and spectroscopy, and modern ophthalmology, to name a few. Performance of an ultrafast fiber laser is well defined by the laser parameters including repetition rate, spectral bandwidth, pulse duration, pulse energy, wavelength tuning range, and average power. During past years, these parameters have been pushed to an unprecedented level. In this paper, we review these enabling technologies and explicitly show that the nonlinear interaction between ultrafast pulses and optical fibers plays the essential role. As a result of rapid development in both active and passive fibers, the toolbox of ultrafast fiber lasers will continue to expand and provide solutions to scientific and industrial problems.
Laser; Nonlinear Optics; Fiber Optics
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapidly rampaged worldwide, causing a pandemic of coronavirus disease (COVID -19), but the biology of SARS-CoV-2 remains under ...investigation. We demonstrate that both SARS-CoV-2 spike protein and human coronavirus 229E (hCoV-229E) or its purified S protein, one of the main viruses responsible for the common cold, induce the transient opening of Pannexin-1 (Panx-1) channels in human lung epithelial cells. However, the Panx-1 channel opening induced by SARS-CoV-2 is greater and more prolonged than hCoV-229E/S protein, resulting in an enhanced ATP, PGE2, and IL-1β release. Analysis of lung lavages and tissues indicate that Panx-1 mRNA expression is associated with increased ATP, PGE2, and IL-1β levels. Panx-1 channel opening induced by SARS-CoV-2 spike protein is angiotensin-converting enzyme 2 (ACE-2), endocytosis, and furin dependent. Overall, we demonstrated that Panx-1 channel is a critical contributor to SARS-CoV-2 infection and should be considered as an alternative therapy.
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•Pannexin-1 (Panx-1) is a critical player in COVID-19 lung pathogenesis•SARS-CoV-2 Panx-1 channel opening is ACE-2/furin/endocytosis dependent•SARS-CoV-2-associated Panx-1 channel opening induces inflammation•Blocking Panx-1 channels reduces viral replication and inflammation
Cell biology; Molecular physiology; Virology
Recent studies have revealed the unique virological characteristics of Omicron, particularly those of its spike protein, such as less cleavage efficacy in cells, reduced ACE2 binding affinity, and ...poor fusogenicity. However, it remains unclear which mutation(s) determine these three virological characteristics of Omicron spike. Here, we show that these characteristics of the Omicron spike protein are determined by its receptor-binding domain. Of interest, molecular phylogenetic analysis revealed that acquisition of the spike S375F mutation was closely associated with the explosive spread of Omicron in the human population. We further elucidated that the F375 residue forms an interprotomer pi-pi interaction with the H505 residue of another protomer in the spike trimer, conferring the attenuated cleavage efficiency and fusogenicity of Omicron spike. Our data shed light on the evolutionary events underlying the emergence of Omicron at the molecular level.
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•Omicron spike receptor-binding domain determines virological characteristics•Spike S375F mutation results in the poor spike cleavage and fusogenicity in Omicron•Acquisition of the spike S375F mutation triggered the explosive spread of Omicron•F375-H505-mediated π-π interaction in the spike determines the phenotype of Omicron
Molecular biology; Virology
Inflammatory response heterogeneity has impeded high-resolution dissection of diverse immune cell populations during activation. We characterize mouse cutaneous immune cells by single-cell RNA ...sequencing, after inducing inflammation using imiquimod and oxazolone dermatitis models. We identify 13 CD45+ subpopulations, which broadly represent most functionally characterized immune cell types. Oxazolone pervasively upregulates Jak2/Stat3 expression across T cells and antigen-presenting cells (APCs). Oxazolone also induces Il4/Il13 expression in newly infiltrating basophils, and Il4ra and Ccl24, most prominently in APCs. In contrast, imiquimod broadly upregulates Il17/Il22 and Ccl4/Ccl5. A comparative analysis of single-cell inflammatory transcriptional responses reveals that APC response to oxazolone is tightly restricted by cell identity, whereas imiquimod enforces shared programs on multiple APC populations in parallel. These global molecular patterns not only contrast immune responses on a systems level but also suggest that the mechanisms of new sources of inflammation can eventually be deduced by comparison to known signatures.
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•Oxazolone pervasively upregulates Jak2/Stat3 expression across T cells and APCs•Il4/Il13 induction in skin by oxazolone is dominated by infiltrating basophils•Imiquimod broadly increases Il17/Il22 and Ccl4/Ccl5, extending to non-T cells•Oxazolone induces more highly compartmentalized immune cell responses than imiquimod
Immunology; Systems Biology
Asperuloside (ASP) is an iridoid glycoside that is extracted from Eucommia leaves. Eucommia is used in traditional Chinese medicine and has a long history of benefits on health and longevity. Here, ...we investigated the impact of ASP on obesity-related metabolic disorders and show that ASP reduces body weight gain, glucose intolerance, and insulin resistance effectively in mice fed with a high-fat diet (HFD). Intestinal dysbiosis is closely linked with metabolic disorders. Our data indicate that ASP achieves these benefits on metabolic homeostasis by reversing HFD-induced gut dysbiosis and by changing gut-derived secondary metabolites and metabolic signaling. Our results indicate that ASP may be used to regulate gut microbiota for the treatment of obesity and type 2 diabetes.
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•Asperuloside (ASP) treatment improved obesity-related metabolic dysfunction in miceASP administration changed intestinal metabolite via modulation of gut microbiotaASP administration increased Parabacteroides and Akkermansia in intestineGut microbiota-derived metabolite improves adipose tissue and intestinal dysfunction
Human Metabolism; Microbiome
Meiotic prophase I is a prolonged G2 phase that ensures the completion of numerous meiosis-specific chromosome events. During meiotic prophase I, homologous chromosomes undergo synapsis to facilitate ...meiotic recombination yielding crossovers. It remains largely elusive how homolog synapsis is temporally maintained and destabilized during meiotic prophase I. Here we show that FBXO47 is the stabilizer of the synaptonemal complex during male meiotic prophase I. Disruption of FBXO47 shows severe impact on homologous chromosome synapsis, meiotic recombination, and XY body formation, leading to male infertility. Notably, in the absence of FBXO47, although once homologous chromosomes are synapsed, the synaptonemal complex is precociously disassembled before progressing beyond pachytene. Remarkably, Fbxo47 KO spermatocytes remain in an earlier stage of meiotic prophase I and lack crossovers, despite apparently exhibiting diplotene-like chromosome morphology. We propose that FBXO47 plays a crucial role in preventing the synaptonemal complex from premature disassembly during cell cycle progression of meiotic prophase I.
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•FBXO47 is a stabilizer of the synaptonemal complex during male meiotic prophase•FBXO47 KO shows precocious disassembly of the synaptonemal complex•FBXO47 may function independently of SCF E3 ligase to maintain homolog synapsis
Biological sciences; Molecular biology; Cell biology
Adhesion G-protein-coupled receptors (aGPCRs) play critical roles in diverse cellular processes in neurobiology, development, immunity, and numerous diseases. The lack of molecular understanding of ...their activation mechanisms, especially with regard to the transmembrane domains, hampers further studies to facilitate aGPCR-targeted drug development. Latrophilin-1/ADGRL1 is a model aGPCR that regulates synapse formation and embryogenesis, and its mutations are associated with cancer and attention-deficit/hyperactivity disorder. Here, we established functional assays to monitor latrophilin-1 function and showed the activation of latrophilin-1 by its endogenous agonist peptide. Via a comprehensive mutagenesis screen, we identified transmembrane domain residues essential for latrophilin-1 basal activity and for agonist peptide response. Strikingly, a cancer-associated mutation exhibited increased basal activity and failed to rescue the embryonic developmental phenotype in transgenic worms. These results provide a mechanistic foundation for future aGPCR-targeted drug design.
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•Latrophilin-1/3 decreases cAMP levels and increases SRE levels in mammalian cells•Mutagenesis of the TM region reveals residues key for adhesion GPCR signaling•A cancer-associated mutation exhibits increased basal activity•The same cancer mutation abolishes latrophilin function in C. elegans development
Molecular Biology; Membrane Architecture; Protein Structure Aspects
The universal importance of epigenetic regulation has become explicit over the last decade. There is now a detailed understanding of the molecular signatures and chromatin-modifying enzymes ...determining epigenetic regulation. For example, the trimethylation of lysine 27 at histone H3 by Polycomb complexes is a hallmark of silenced gene expression conserved across animal and plant kingdoms. The repressive activity of Polycomb complexes is balanced by the histone demethylase activity of Jumonji C-domain proteins. There has been a lot of research on Polycomb functions and H3K27 methylation; however, until recently, little was known about the role of histone H3K27 demethylases. Here, we review the role of Jumonji C-domain proteins from the plant development perspective. We will recall the history of histone lysine demethylation and explore the recent advances on the H3K27 demethylases in plant biology. Conserved and novel genomic functions of these epigenetic regulators will be discussed.
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•Jumonji C-domain proteins demethylate the repressive epigenetic mark H3K27me3•Plant H3K27me3 demethylases include ELF6, REF6, JMJ13, JMJ30, and JMJ32•Plant H3K27me3 demethylases regulate a wide range of developmental processes
Biological Sciences; Plant Biology; Plant Development
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