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Simultaneously increasing the activity and stability of the single-atom active sites of M–N–C catalysts is critical but remains a great challenge. Here, we report an Fe–N–C catalyst with nitrogen-coordinated iron clusters and closely surrounding Fe–N 4 active sites for oxygen reduction reaction in acidic fuel cells. A strong electronic interaction is built between iron clusters and satellite Fe–N 4 due to unblocked electron transfer pathways and very short interacting distances. The iron clusters optimize the adsorption strength of oxygen reduction intermediates on Fe–N 4 and also shorten the bond amplitude of Fe–N 4 with incoherent vibrations. As a result, both the activity and stability of Fe–N 4 sites are increased by about 60% in terms of turnover frequency and demetalation resistance. This work shows the great potential of strong electronic interactions between multiphase metal species for improvements of single-atom catalysts. It is challenging to break the activity–stability trade-off in Fe–N–C fuel cell catalysts. Here, the authors show that interactions between iron atoms and clusters accelerate reaction kinetics and suppress demetalation to improve fuel cell stability.

Porcine epidemic diarrhea (PED), caused by the porcine epidemic diarrhea virus (PEDV), is an acute and highly contagious intestinal disease that inflicts substantial economic losses on the global swine industry. The nucleocapsid (N) protein of PEDV plays a critical role during viral infection and replication. In this study, the full-length N gene was cloned and expressed using the prokaryotic expression vector pET-32a (+). The purified recombinant N protein was used to immunize BALB/c mice. Subsequently, splenocytes from the immunized mice were fused with SP2/0 cells, and hybridoma cell lines secreting monoclonal antibodies (mAbs) against N protein were screened via indirect ELISA. The linear B-cell epitopes recognized by the mAbs were mapped using truncated N protein fragments. Results showed that three stable hybridoma cell lines (1A3, 1G1 and 1A10) secreting N protein-specific mAbs were obtained. Epitope mapping revealed that mAbs 1A3 and 1G1 recognized the epitope 71SNWHF75, whereas mAb 1A10 recognized 66RIEQP70. Bioinformatics analysis indicated that these epitopes are highly conserved among the analyzed PEDV strains and show no cross-reactivity with the N proteins of other coronaviruses. These findings could provide valuable experimental materials for further investigation of the N protein’s structure and function and support the development of diagnostic assays and subunit antigen vaccine for PEDV.

Avian infectious bronchitis is caused by the avian infectious bronchitis virus (IBV), which poses a significant threat to the poultry industry and public health. The S1 protein of IBV plays a crucial role in the process of the virus invading host cells. To investigate the significant antigenic targets within the S1 protein, in this study, the truncated S1 sequence of the IBV M41 strain was cloned with approximately 660 bp and expressed. After purification and renaturation, the recombinant S1 protein was immunized into BALB/c mice. Then, following fusion with lymphocytes and SP2/0 cells, the indirect ELISA and Western blotting techniques were employed to screen hybridoma cell lines secreting monoclonal antibodies (mAbs) targeting the S1 protein. Antigenic epitopes of the mAbs were identified using truncated S1 fragments and peptide scanning. The results indicated that three hybridoma cell lines stably secreting S1 protein-specific mAbs (2A10, 4E9, and 5E12) were screened. The heavy chains of the three mAbs were IgG1, and all three mAbs contained kappa light chains. The identified minimal B-cell epitopes were 132RVSAMK137 and 142FYNLTV147. Homology analysis showed these both epitopes were conserved across IBV subtypes and located on the S1 protein surface. The conserved β-sheet epitope 132RVSAMK137 and the surface-exposed, flexible loop epitope 142FYNLTV147 serve as ideal targets for broad-spectrum diagnostics and early infection detection, respectively. These epitopes provide unique structural advantages for antibody binding, enabling the design of multivalent epitope vaccines or the development of immunomodulatory drugs. They offer novel biomaterials and targets for antibody-based drug development and rapid detection methods for avian infectious bronchitis virus (IBV), holding significant potential for the prevention and control of IBV.

Non-precious-metal or metal-free catalysts with stability are desirable but challenging for proton exchange membrane fuel cells. Here we partially unzip a multiwall carbon nanotube to synthesize zigzag-edged graphene nanoribbons with a carbon nanotube backbone for electrocatalysis of oxygen reduction in proton exchange membrane fuel cells. Zigzag carbon exhibits a peak areal power density of 0.161 W cm −2 and a peak mass power density of 520 W g −1 , superior to most non-precious-metal electrocatalysts. Notably, the stability of zigzag carbon is improved in comparison with a representative iron-nitrogen-carbon catalyst in a fuel cell with hydrogen/oxygen gases at 0.5 V. Density functional theory calculation coupled with experimentation reveal that a zigzag carbon atom is the most active site for oxygen reduction among several types of carbon defects on graphene nanoribbons in acid electrolyte. This work demonstrates that zigzag carbon is a promising electrocatalyst for low-cost and durable proton exchange membrane fuel cells. Cost and stability of catalysts hinder widespread use of proton exchange membrane fuel cells. Here the authors synthesize zigzag-edged graphene nanoribbons for electrocatalysis of oxygen reduction. Employment of such a metal-free catalyst in a fuel cell yields remarkable power density and durability.

In the context of the growing emphasis on sustainable development and building safety performance, wooden architecture will attract increasing attention due to its low-carbon characteristics and excellent seismic resistance. In this study, the bibliometric software Citespace is used for data visualization analysis based on the literature related to Chinese wooden architecture in the China National Knowledge Infrastructure (CNKI) and the Web of Science (WOS) databases, aiming to construct an analytical framework that integrates quantitative visualization and qualitative thematic interpretation which could reveal the current status, hotspots, and frontier trends of research in this field. The results show the following: Research on Chinese wooden architecture has shown a steady growth trend, indicating that it has received attention from an increasing number of scholars. Researchers and institutions are mainly concentrated in higher learning and research institutions in economically developed regions. Research hotspots cover subjects such as seismic performance, mortise–tenon structures, imitation wood structures, Dong architecture, Liang Sicheng, and the Society for the Study of Chinese Architecture. The research process of Chinese wooden architecture can be divided into three stages: the macro stage, the specific deepening stage, and the inheritance application and interdisciplinary integration stage. In the future, the focus will be on interdisciplinary research on wooden architecture from ethnic minority cultures and traditional dwellings.

The Fe–N–C catalysts with atomic Fe1 active sites are the most active low-cost alternatives to Pt/C for the large-scale application of proton exchange membrane fuel cells (PEMFCs). However, the activity performance of Fe–N–C catalysts still lags behind that of Pt catalysts, especially in PEMFC devices. This review focuses on the three key factors affecting the activity of Fe–N–C catalysts and the advanced synthesis strategies for high-performance Fe–N–C. Based on the literature data, we have summarized the relationship between catalyst iron content and effective site concentration, pointed out the current difficulties encountered in catalyst design, and proposed several aspects that future research needs to focus on. We believe this review could guide the rational design of Fe–N–C type of single-atom catalysts and promote the development of low-cost PEMFCs.

Amino acids (AAs), serving as the primary monomer of peptides and proteins, are widely present in nature. Benefiting from their inherent advantages, such as chemical diversity, low cost, ease of modification, chirality, biosafety, and bio-absorbability, AAs have been extensively exploited to create self-assembled nanostructures and supramolecular soft materials. In this review article, we systematically describe the recent progress regarding amino acid-derived assembly and functional soft materials. A brief background and several classified assemblies of AAs and their derivatives (chemically modified AAs) are summarized. The key non-covalent interactions to drive the assembly of AAs are emphasized based on the reported systems of self-assembled and co-assembled AAs. We discuss the molecular design of AAs and the general rules behind the hierarchical nanostructures. The resulting soft materials with interesting properties and potential applications are demonstrated. The conclusion and remarks on AA-based supramolecular assemblies are also presented from the viewpoint of chemistry, materials, and bio-applications.

Lung cancer is the main cause of cancer-related deaths, and non-small cell lung cancer (NSCLC) is the most common type. Understanding the potential mechanisms, prognosis, and treatment aspects of NSCLC is essential. This study systematically analyzed the correlation between mitophagy and NSCLC. Six mitophagy-related feature genes ( SRC , UBB , PINK1 , FUNDC1 , MAP1LC3B , and CSNK2A1 ) were selected through machine learning and used to construct a diagnostic model for NSCLC. These feature genes are closely associated with the occurrence and development of NSCLC. Additionally, NSCLC was divided into two subtypes using unsupervised consensus clustering, and their differences in clinical characteristics, immune infiltration, and immunotherapy were systematically analyzed. Furthermore, the interaction between mitophagy-related genes (MRGs) and immune cells was analyzed using single-cell sequencing data. The findings of this study will contribute to the development of potential diagnostic biomarkers for NSCLC and the advancement of personalized treatment strategies.

Coronaviruses (CoVs) comprise a group of important human and animal pathogens. Despite extensive research in the past 3 years, the host innate immune defense mechanisms against CoVs remain incompletely understood, limiting the development of effective antivirals and non-antibody-based therapeutics. Here, we performed an integrated transcriptomic analysis of porcine jejunal epithelial cells infected with porcine epidemic diarrhea virus (PEDV) and identified cytidine/uridine monophosphate kinase 2 (CMPK2) as a potential host restriction factor. CMPK2 exhibited modest antiviral activity against PEDV infection in multiple cell types. CMPK2 transcription was regulated by interferon-dependent and interferon regulatory factor 1 (IRF1)-dependent pathways post-PEDV infection. We demonstrated that 3′-deoxy-3′,4′-didehydro-cytidine triphosphate (ddhCTP) catalysis by Viperin, another interferon-stimulated protein, was essential for CMPK2’s antiviral activity. Both the classical catalytic domain and the newly identified antiviral key domain of CMPK2 played crucial roles in this process. Together, CMPK2, viperin, and ddhCTP suppressed the replication of several other CoVs of different genera through inhibition of the RNA-dependent RNA polymerase activities. Our results revealed a previously unknown function of CMPK2 as a restriction factor for CoVs, implying that CMPK2 might be an alternative target of interfering with the viral polymerase activity.

Atomically dispersed transition metal‐Nx sites have emerged as a frontier for electrocatalysis because of the maximized atom utilization. However, there is still the problem that the reactant is difficult to reach active sites inside the catalytic layer in the practical proton exchange membrane fuel cell (PEMFC) testing, resulting in the ineffective utilization of the deeply hided active sites. In the device manner, the favorite structure of electrocatalysts for good mass transfer is vital for PEMFC. Herein, a facile one‐step approach to synthesize atomically dispersed Fe‐Nx species on hierarchically porous carbon nanostructures as a high‐efficient and stable atomically dispersed catalyst for oxygen reduction in acidic media is reported, which is achieved by a predesigned hierarchical covalent organic polymer (COP) with iron anchored. COP materials with well‐defined building blocks can stabilize the dopants and provide efficient mass transport. The appropriate hierarchical pore structure is proved to facilitate the mass transport of reactants to the active sites, ensuring the utilization of active sites in devices. Particularly, the structurally optimized HSAC/Fe‐3 displays a maximum power density of up to 824 mW cm−2, higher than other samples with fewer mesopores. Accordingly, this work will offer inspirations for designing efficient atomically dispersed electrocatalyst in PEMFC device. A facile one‐step approach to synthesize atomically dispersed Fe‐Nx species on hierarchically porous carbon nanostructures is reported, which facilitates the mass transport of reactants and electrolytes to the active sites, thus ensuring the efficient utilization of active sites in practical PEMFC devices.