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The facile reconfiguration of phases plays a pivotal role in enhancing the electrocatalytic production of H2 through heterostructure formation. While chemical methods have been explored extensively for this purpose, plasma-based techniques offer a promising avenue for achieving heterostructured nano-frameworks. However, the conventional plasma approach introduces complexities, leading to a multi-step fabrication process and challenges in precisely controlling partial surface structure modulation due to the intricate interaction environment. In our pursuit of heterostructures with optimized oxygen evolution reaction (OER) behavior, we have designed a facile auxiliary insulator-confined plasma system to directly attain a Ni3N–NiO heterostructure (hNiNO). By meticulously controlling the surface heating process during plasma processing, such approach allows for the streamlined fabrication of hNiNO nano-frameworks. The resulting nano-framework exhibits outstanding catalytic performance, as evidenced by its overpotential of 320 mV at a current density of 10 mA·cm−2, in an alkaline environment. This stands in stark contrast to the performance of NiO-covered Ni3N fabricated using the conventional plasma method (sNiNO). Operando plasma diagnostics, coupled with numerical simulations, further substantiates the influence of surface heating due to auxiliary insulator confinement of the substrate on typical plasma parameters and the formation of the Ni3N–NiO nanostructure, highlighting the pivotal role of controlled surface temperature in creating a high-performance heterostructured electrocatalyst. [ABSTRACT FROM AUTHOR]

Amyloid fibrillation is associated with a great variety of human diseases, such as Alzheimer's and Huntington's diseases. A fluorescence assay for amyloid fibrillation detection and inhibitor screening was developed based on the fact that the fluorescence emission of gold nanoclusters (Au NCs) is largely enhanced upon adding amyloids, such as lysozyme amyloid fibers. A good linear relationship exists between the enhanced fluorescence intensity of Au NCs and lysozyme fiber within the concentration range of 0–0.05 mg mL−1. This ultra-sensitive method can detect the protein fiber earlier than thioflavin T (THT), allowing more time for disease treatment. Furthermore, Au NCs have many advantages over the classical probe (i.e., THT), such as large Stokes shifts and low toxicity. We selected ascorbic acid as a representative inhibitor and used this method to screen inhibitors. If inhibitors are added when incubating lysozyme, the lysozyme fibrosis process will be crimped, decreasing the amount of lysozyme fibers. [ABSTRACT FROM AUTHOR]

Background: Human norovirus (HuNoV) is the leading cause of acute nonbacterial gastroenteritis globally, and its infection is usually self-limited, so most people become past Norovirus (NoV)-infected individuals. It is known that some antibody responses may play a critical role in preventing viral infection and alleviating disease; however, the characteristics and functions of particular antibody responses in persons with previous infections are not fully understood. Capsid proteins, including VP1 and VP2, are crucial antigenic components of NoV and may regulate antibody immune responses, while epitope-specific antibody responses to capsid proteins have not been comprehensively characterized. Methods: We prepared purified VP1 and VP2 proteins by ion exchange chromatography and measured serum antigen-specific IgG levels in 398 individuals by ELISA. Overlapping 18-mer peptides covering the full length of VP1 and VP2 were synthesized, and then we identified linear antigenic epitopes from 20 subjects with strong IgG positivity. Subsequently, specific antibody responses to these epitopes were validated in 185 past infected individuals, and the conservation of epitopes was analyzed. Finally, we obtained epitope-specific antiserum by immunizing mice and expressed virus-like particles (VLPs) in an insect expression system for a blockade antibody assay to evaluate the receptor-blocking ability of epitope-specific antibodies. Results: The IgG responses of VP1 were significantly stronger than those of VP2, both of which had high positive rates of over 80%. The overall positive rate of VP1-IgG and/or VP2-IgG was approximately 94%, which may be past NoV-infected individuals. Four linear antigenic B-cell epitopes of capsid proteins were identified, namely, VP1199–216, VP1469–492, VP297–120, and VP2241–264, all of which were conserved. The IgG response rates of the above epitopes in past NoV-infected individuals were 38.92%, 22.16%, 8.11% and 28.11%, respectively. In addition, VP1199–216- and VP1469–492-specific antibodies can partially block the binding of VLPs to the receptor histo-blood group antigen (HBGA). Conclusion: This is the first study to describe specific antibody responses of VP2 and to identify its B-cell epitopes. Our findings offer data for a more thorough understanding of norovirus capsid protein-specific IgG responses and could provide useful information for designing and developing vaccines. [ABSTRACT FROM AUTHOR]

In order to solve the problem of poor rheological properties of solid‐free drilling fluids in salt‐bearing formations and prevent drilling accidents such as lost circulation, formation collapse, and wellbore instability, it is crucial to develop a new type of viscosifier. In this study, a salt‐responsive Gemini viscoelastic surfactant (NT‐1) was synthesized by using erucamide as a hydrophobic chain and introducing a benzene ring and a carboxyl group into the linker. In addition, it is used as a viscosifier for solid‐free drilling fluids. The structure of the surfactant was characterized by 1H nuclear magnetic resonance (NMR), 13C NMR, Fourier transform infrared spectroscopy, and electrospray ionization tandem mass spectrometry (ESI‐MS), and its physicochemical properties were determined by surface tensiometer, thermogravimetric‐differential scanning calorimetry, dynamic lighting scattering and rheometer. Its performance in solid‐free drilling fluids was evaluated according to the American Petroleum Institute (API) standard. The results show that the surfactant has a low critical micelle concentration (31.74 μmol/L), excellent thermal stability and water solubility. In particular, NT‐1 can self‐assemble into worm‐like micelles under the action of salt, and the spatial network structure formed by the interweaving of these micelles can endow the drilling fluid with good rheology and viscoelasticity. NT‐1 is compatible with conventional drilling fluid polymer additives, which can effectively improve solid‐free drilling fluids' rheological properties and fluid loss properties in salt layers. The temperature resistance in drilling fluid systems can reach 120°C. This work verifies the feasibility of using viscoelastic surfactants as viscosifiers in solid‐free drilling fluids and provides new ideas for developing salt‐responsive smart drilling fluids. [ABSTRACT FROM AUTHOR]