Hydrogel modified porous matrix with the super-wetting surface (i.e., superhydrophilic/underwater super-oleophobic) is ideal for oil/water separation. However, the deterioration in mechanical strength and separation efficiency during the swelling process and complicated synthesis procedure limits its industrial application. In this study, a strategy of using ethanol to dynamically regulate the hydrogen bond crosslinking between polyvinyl alcohol (PVA) and tannic acid (TA) is proposed to prepare a "hydrogel paint", which can be simply applied on the porous substrate surface by different one-step operations (dipping, brushing, spraying, etc.) without additional cross-linking. The underline mechanism is attributed to the re-establishment of intermolecular hydrogen bond mediated cross-linking between PVA and TA during ethanol evaporation. Consequently, the resultant hydrogel coating exhibits ultra-high strength (>10 MPa), swelling volume stability, and excellent oil-water separation efficiency (>99%). This study will provide new insights into the scalable fabrication of hydrogel-coated porous materials for oil/water separation in industrial scenarios.

B cell response plays a critical role against SARS-CoV-2 infection. However, little is known about the diversity and frequency of the paired SARS-CoV-2 antigen-specific BCR repertoire after SARS-CoV-2 infection. Here, we performed single-cell RNA sequencing and VDJ sequencing using the memory and plasma B cells isolated from five convalescent COVID-19 patients, and analyzed the spectrum and transcriptional heterogeneity of antibody immune responses. Via linking BCR to antigen specificity through sequencing (LIBRA-seq), we identified a distinct activated memory B cell subgroup (CD11chighCD95high) had a higher proportion of SARS-CoV-2 antigen-labeled cells compared with memory B cells. Our results revealed the diversity of paired BCR repertoire and the non-stochastic pairing of SARS-CoV-2 antigen-specific immunoglobulin heavy and light chains after SARS-CoV-2 infection. The public antibody clonotypes were shared by distinct convalescent individuals. Moreover, several antibodies isolated by LIBRA-seq showed high binding affinity against SARS-CoV-2 receptor-binding domain (RBD) or nucleoprotein (NP) via ELISA assay. Two RBD-reactive antibodies C14646P3S and C2767P3S isolated by LIBRA-seq exhibited high neutralizing activities against both pseudotyped and authentic SARS-CoV-2 viruses in vitro. Our study provides fundamental insights into B cell response following SARS-CoV-2 infection at the single-cell level.

High-temperature-resistant dielectric films, the heart of energy storage components in film capacitors, are key elements to ensure that the capacitors operate properly in harsh environments. Herein, a kind of flexible thermal-resistant poly­(arylene ether nitrile) (TR-PEN) dielectric film with controllable high-temperature resistance is fabricated through post self-crosslinking of PEN at different temperatures for different times. The dielectric films can present extremely high thermal stability (T g > 370 °C), a long service life at 300 °C (4.5 × 104 min, 95 wt % of the residual weight), and a low temperature coefficient of dielectric constant from 50 to 300 °C (<5 × 10–4 °C–1). The retention of the energy density of TR-PEN350 at 300 °C is higher than 80% compared with that at room temperature. These results indicate that the TR-PEN films can be used over a long term as capacitor films at temperatures up to 300 °C. Besides, the simple and controllable fabrication technique for the TR-PEN can be easily industrialized.

The development of multifunctional separators can be an effective solution for solving the lithium dendrite and safety issues of lithium metal batteries (LMBs). This study reveals an interfacial reaction protocol to prepare a functional separator to regulate lithium-ion transport and enhance the safety of LMBs. Specifically, the well-organized anionphilic MOFs layers are in situ grafted on both sides of porous super-engineering polyarylene ether nitrile (PEN) membranes pre-modified with polydopamine (PDA), which leads to sandwiched MOF/PEN@PDA/MOF multifunctional separators. Electrochemical tests prove that the optimized separator acts as a "Li-ion guides" to balance the internal electric field and limit the free migration of anions, which extends the "Sand's time" of lithium dendrite nucleation and contributes a high Li + transfer number of 0.81. On account of the alleviated interface side reactions, the optimized battery exhibits a highly stable lithium plating-stripping cycle of over 500 h. Meanwhile, the functional separator shows better thermal stability than its conventional polypropylene counterpart. Thanks to these features, the assembled LFP/Li cells with optimized separator exhibit stable cycling performance and high coulombic efficiency of 98% even at 90 °C. The current study opens a new path to designing separators for solving the lithium dendrite and safety issues of LMBs.

Bacteria encode a variety of adaptations that enable them to survive during zinc starvation, a condition which is encountered both in natural environments and inside the human host. In Vibrio cholerae, the causative agent of the diarrheal disease cholera, we have identified a novel member of this zinc starvation response, a cell wall hydrolase that retains function and is conditionally essential for cell growth in low-zinc environments. Other Gram-negative bacteria contain homologs that appear to be under similar regulatory control. These findings are significant because they represent, to our knowledge, the first evidence that zinc homeostasis influences cell wall turnover. Anti-infective therapies commonly target the bacterial cell wall; therefore, an improved understanding of how the cell wall adapts to host-induced zinc starvation could lead to new antibiotic development. Such therapeutic interventions are required to combat the rising threat of drug-resistant infections.