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The main protease (M pro ) is a pivotal target in the life cycle of feline coronavirus (FCoV), which causes a high mortality feline disease, feline infectious peritonitis (FIP). Virtual screening was performed against the feline coronavirus M pro to find active compounds with low toxicity from a library of natural products. Eighty-six compounds were selected by using the rank of docking score and binding pose analysis. In the enzyme-based assay, 12 compounds showed a more than 40% inhibitory effect on M pro at a concentration of 200 μmol/L. The IC 50 values of theaflavin 3,3'-digallate (25.0 μmol/L), sennoside C (25.2 μmol/L), pinocembrin-galloyl-HHDP-G (33.3 μmol/L), and thonningianin A (50.6 μmol/L) were determined. In addition, curcuminoids (51.7-64.3% under 200 μmol/L) and flavonoids (41.3-60.3% under 200 μmol/L) also exhibited certain inhibitory effects on M pro . Molecular dynamics simulations and binding free energy calculations were employed to reveal the atomic details of the binding of these compounds with M pro . The results showed that most of the compounds formed significant interactions with key residues on the catalytic site, such as His-41, Cys-144, and Glu-165. These compounds could serve as a starting point to develop FCoV M pro inhibitors with high potency., Competing Interests: The authors declare no competing financial interest., (© 2025 The Authors. Published by American Chemical Society.)

Solar energy is an ideal clean and inexhaustible energy source. Solar-driven formic acid (FA) dehydrogenation is one of the promising strategies to address safety and cost issues related to the storage, transport, and distribution of hydrogen energy. For FA dehydrogenation, the O-H and C-H cleavages are the key steps, and developing a photocatalyst with the ability to break these two bonds is critical. In this work, both density functional theory (DFT) calculation and experimental results confirmed the positive synergistic effect between brookite and rutile TiO 2 for O-H and C-H cleavage in HCOOH. Further, brookite TiO 2 is beneficial to the generation of the • OH radical and significantly promotes C-H cleavage in formate. Under optimized conditions, the H 2 production efficiency of FA dehydrogenation can reach up to 30.4 μmol·mg -1 ·h -1 , which is the highest value compared with similar reported TiO 2 -based systems and over 1.7 times the reported highest value of Au 0.75 Pd 0.25 /TiO 2 photocatalysts. More importantly, after more than 42 days (>500 h) of irradiation, the system still demonstrated high H 2 production activity, indicating the potential for practical application. This work provides a valuable strategy to improve both the efficiency and stability of photocatalytic FA dehydrogenation under mild conditions.

Wearable pressure sensors with ultrahigh sensitivity and flexibility have garnered tremendous attention because of their abilities to mimic the human somatosensory system and perceive surrounding pressure distribution. Herein, an ultrasensitive pressure sensor was fabricated with surface-patterned nanofibrous membranes (SPNMs) via a facile replica method from available plain-weaved nylon textiles. The SPNMs were composed of internal three-dimensional interpenetrating polyolefin elastomer nanofibers and silver nanowires (Ag NWs). The effects of the geometry of surface patterns and the density of the Ag NW network on the sensing performance of the assembled pressure sensor were systematically investigated. The results indicated that clavate groove-shaped surface patterns improved the sensitivity and a larger groove spacing contributed to higher sensitivities, whereas denser Ag NWs would reduce the sensing performance. The optimal pressure sensor assembled with SPNMs-45 and a Ag NW fraction of 3.8% showed high sensitivity (19.4 kPa -1 ) below the pressure of 2.76 kPa, a low detection limit (<1.6 Pa), fast response (30 and 42 ms), as well as excellent durability. These outstanding performances demonstrated its promising potential for wearable electronic applications, like detecting the spatial pressure distribution and monitoring human muscle motions.

Highly stretchable and conductive fibers have attracted great interest as a fundamental building block for the next generation of textile-based electronics. Because of its high conductivity and high aspect ratio, the Ag nanowire (AgNW) has been considered one of the most promising conducting materials for the percolation network-based conductive films and composites. However, the poor dispersibility of AgNWs in hydrophobic polymers has hindered their application to stretchable conductive composite fibers. In this paper, we present a highly stretchable and conductive composite fiber from the co-spinning of surface-modified AgNWs and thermoplastic polyurethane (PU). The surface modification of AgNWs with a polyethylene glycol derivative improved the compatibility of PU and AgNWs, which allowed the NWs to disperse homogeneously in the elastomeric matrix, forming effective percolation networks and causing the composite fiber to show enhanced electrical and mechanical performance. The maximum AgNW mass fraction in the composite fiber was 75.9 wt %, and its initial electrical conductivity was as high as 14 205 S/cm. The composite fibers also exhibited superior stretchability: the maximum rupture strain of the composite fiber with 14.6 wt % AgNW was 786%, and the composite fiber was also conductive even when it was stretched up to 200%. In addition, 2-dimensional (2-D) Ag nanoplates were added to the AgNW/PU composite fibers to increase the stability of the conductive network under repeated stretching and releasing. The Ag nanoplates acted as a bridge to effectively prevent the AgNWs from slippage and greatly improved the stability of the conductive network.

We theoretically investigate the collapse (i.e., wetting) transition of the air-water interface on fully submerged superhydrophobic surfaces with micro-sized grooves under the fluctuating water pressure and the diffusion of the trapped air pockets. For the analysis, a nonlinear oscillator equation to describe the dynamics of the two-dimensional air-water interface on a single groove is derived, which is solved for a range of parameters of groove geometry and harmonically fluctuating water pressure. The results show that the pressure fluctuation across the interface encourages the early collapse of a plastron before reaching the critical hydrostatic pressure (i.e., maximum immersion depth) predetermined by the geometry. The dependence of plastron longevity on the surface geometry is found such that the plastron on a narrow groove (≤∼5 μm) (collapses mostly due to gas diffusion) lasts days while the ones on wider grooves (>∼35-45 μm, for example), more susceptible to the oscillating pressure, last a much shorter duration. The interplay between the air compression due to water impalement and the change of the volume of impaled water due to gas diffusion determines the response of plastron to fluctuating water pressure, which is analyzed in detail through the introduction of nondimensional parameters, and the critical groove width (most vulnerable to the external perturbations) is explained further. Finally, as a countermeasure to the fluctuating water pressure, it is suggested that the enhanced advancing contact angle of the groove sidewall (e.g., hierarchical structure) mitigates the negative effects.

Synthesis of silver nanoplates was studied in the modified polyol method, where the nucleation and seed stage occurred in a poly(ethylene glycol) (PEG)-water mixture solution, and the growth stage happened in the PEG environment. The morphological evolution of nanoplates was characterized using UV, SEM, and TEM. Interestingly, plane nanostructures with unusual jagged edges were finally formed in our modified polyol method. Using TEM, we observed the medium state of fusion between two nanoplates, resulting in generating unusual jagged edges. Therefore, a novel two-dimensional oriented attachment occurred in our modified polyol method, which involves smaller nanoplates as the building blocks. Further control experiments showed that the presence of water could break this kinetic preferred reactivity, leading to the formation of nanoparticles.

Folate receptor-alpha (FR) is a promising cellular marker for tumor-specific drug delivery. Conjugation of folic acid to therapeutic and imaging agents has been shown to enhance their delivery to FR (+) cancer cells in vitro and in tumor-bearing mice via an FR-mediated cellular uptake mechanism. In this study, immunoglobulin G (IgG) was conjugated to folate and evaluated as a therapeutic antibody against folate receptor (FR)-positive tumors. Murine IgG (mIgG) was conjugated to folate via an amide bond to yield folate-conjugated mIgG (f-mIgG) that contained an average of approximately 2.6 folates per molecule. Selective uptake of f-IgG by FR (+) tumor cells was determined by fluorescence microscopy and by flow cytometry. Lysis of L1210JF cells by NK cells from murine donors was increased 1.4-9.0-fold at the effector:target (E:T) ratio of 25:1, relative to control mIgG. In mice bearing L1210JF tumors, f-mIgG was found to significantly inhibit tumor growth and to have prolonged the median survival time (MeST). Significantly, the antitumor efficacy of f-mIgG was greatly increased when combined with liposomal G3139, an 18-mer phosphorothioate oligonucleotide. In fact, the combination resulted in a 100% cure rate among the tumor-bearing mice. Injection of f-mIgG significantly increased serum INF-gamma and IL-6 level in mice compared with mIgG and dramatically increased serum INF-gamma and IL-6 level when combined with liposomal G3139. These results suggested that f-IgG, a novel immunotherapy agent, has potent activity as a therapeutic antibody to the FR-positive cancer, and the therapeutic activity is enhanced by immunomodulatory agents.

We finely tuned the Au shell on a polystyrene microsphere of 2 microm in diameter to achieve a strong surface enhanced raman scattering (SERS)-active platform so that the molecules on a single microspherical shell surface produce their own fingerprint SERS spectra. The proposed microshells can be easily and individually manipulated under a conventional optical microscope using a micropipet and act as a sensitive probe to obtain the SERS spectra of the monolayer of molecules on Pt as well as Au surfaces without any requirement of special surface morphology or modification for inducing SERS activity. Well-defined SERS spectra can be obtained at a very short acquisition time of milliseconds, suggesting useful applications of the present system based on the decoding of the SERS-active barcodes on individually functionalized microshells.

Mixtures of Ag(hexanoate) and Ag(palmitate) give thermoreversible gels at very low concentration in toluene. The framework of the gel is composed of the branched nanosized fibers, contrary to the microsized wire precipitates of silver(I) carboxylates. The randomness of mixed-ligand silver(I) carboxylate polymeric chains hinders the crystallization process, resulting in very thin fibrils. This may be a new approach to design and control the properties of materials, which do not have properties involving gels or nanostructures in a conventional process.

A biodegradable two block copolymer, poly(epsilon-caprolactone)-b- poly(gamma-benzyl-L-glutamic acid) (PCL-PBLG) was synthesized successfully by ring-opening polymerization of N-carboxyanhydride of gamma-benzyl-L-glutamate (BLG-NCA) with aminophenyl-terminated PCL as a macroinitiator. The aminophenethoxyl-terminated PCL was prepared via hydrogenation of a 4-nitrophenethoxyl-terminated PCL, which was novelly obtained from the polymerization of epsilon-caprolactone (CL) initiated by amino calcium 4-nitrobenzoxide. The structures of the block copolymer and its precursors from the initial step of PCL were confirmed and investigated by 1H NMR, FT-IR, GPC, and FT-ICRMS analyses and DSC measurements.