Search Results (155)

Background/Objectives: Diet plays a critical role in the development of inflammatory bowel disease (IBD). Our previous work demonstrated that oats and oat bran alleviate dextran sulfate sodium (DSS)-induced colitis in mice by modulating the gut microbiota. Methods: To further explore the underlying mechanisms, this study combined metabolomic and transcriptomic analyses to systematically compare the effects of whole oats and oat bran interventions on chronic colitis. Results: Untargeted metabolomics analysis identified three key metabolites, ursodeoxycholic acid, 3-(3-hydroxyphenyl)propionic acid, and avenanthramide C. The interactions between these metabolites and core proteins of the IL-17 signaling pathway (IL-17A, TRAF6, and ACT1) were evaluated via molecular docking. Transcriptomic and RT-qPCR analyses revealed that both oats and oat bran interventions modulated the IL-17, PI3K-Akt, and TNF signaling pathways. These treatments significantly upregulated the expression of tight junction proteins (claudin-1, claudin-5, occludin) while reducing levels of inflammatory cytokines and chemokines. Molecular docking results demonstrated stable binding between the three metabolites and target proteins primarily through hydrogen bonding and electrostatic interactions, with ursodeoxycholic acid exhibiting the highest binding affinity. Conclusions: Collectively, these findings suggest that oats and oat bran may alleviate chronic colitis by modulating the IL-17 signaling pathway and enhancing intestinal barrier function. Full article

Aiming at the unclear mechanisms of fluid migration in nanopore-throat systems within tight oil reservoirs, this study focuses on the microscopic interactions at the oil–water interface in nanoconfined spaces. Based on molecular dynamics simulation, water-flooding models within nanopores of tight oil reservoirs under varying salinity conditions were constructed. The microscopic flow behaviors of oil and water in the pores were investigated, and the mechanism by which interfacial hydrogen bonding influences displacement efficiency under nanoconfinement was elucidated. The results demonstrate that due to the strong hydrogen bonding interactions between acetic acid and water, it is impossible to establish an effective displacement process or form stable displacement pathways within the pores. The extensive hydrogen-bonding network formed by acetic acid molecules at the oil–water interface severely restricts the transport capacity of water. Salinity exerts a nonlinear regulatory effect on hydrogen bonding. High-salinity (246.5 g/L) waterflooding shortens hydrogen bond lengths, enhances local bonding strength, and restricts the expansion of water channels; low-salinity (21.9 g/L) waterflooding mitigates ionic interference, resulting in the highest diffusion capacity of alkanes. The diffusion coefficient increases by 1.4 times compared to that under high-salinity conditions, leading to the highest degree of crude oil mobility. The research findings provide important guidance for enhanced oil recovery in tight oil reservoirs. Full article

Background/Objectives: Microtubule-targeting agents remain foundational components of anticancer chemotherapy, yet their clinical utility is constrained by resistance and toxicity. Methods: Here, we present a theoretical exploration of a plausible “dual” binding pocket that spans the α-tubulin pironetin site and the inter-subunit todalam site. Eight virtual chimeric ligands, each merging key pharmacophoric elements of pironetin and todalam, were constructed and covalently docked to Cys316 of α-tubulin. Results: Covalent docking followed by 200 ns all-atom molecular dynamics simulations revealed that two derivatives (compounds 4 and 8) stably occupy the merged cavity, simultaneously anchoring in the pironetin region via Michael addition and in the todalam region via π-stacking and hydrogen bonding. These hybrids preserved the critical hydrogen-bonding networks of both parent ligands and exhibited low ligand RMSD values (~1.5 Å) and compact radii of gyration throughout the simulations, indicating a tight, persistent binding. Estimated HYDE affinities of 1.5 µM for compound 4 and 17.6 µM for compound 8, calculated with SeeSAR, suggest that covalent engagement can compensate for moderate non-covalent binding scores. Conclusions: In summary, our results provide compelling grounds for developing a new class of α-tubulin inhibitors that engage the hybrid pocket, laying a foundation for the structure-guided synthesis of first-in-class dual-site compounds capable of overcoming resistance to conventional microtubule-targeting drugs. Full article

Conductive hydrogels show great promise for wearable sensors but suffer from low sensitivity in small strain ranges. In this study, we developed a micropatterned composite hydrogel sheet (thickness: 1.2 ± 0.1 mm) by constructing a continuous electronic conductive network of carbon nanotubes (CNTs) on a highly crosslinked micropatterned hydrogel sheet. The sheet was fabricated via a two-step synthesis of a polyvinyl alcohol/polyacrylic acid polymer network—crosslinked by Zr⁴⁺ in a glycerol-water system—using sandpaper as the template. The first step ensured tight conformity to the template, while the second step preserved the micropattern’s integrity and precision. The reverse sandpaper micropattern enables secure bonding of CNTs to the hydrogel and induces localized stress concentration during stretching. This triggers controllable cracking in the conductive network, allowing the sensor to maintain high sensitivity even in small strain ranges. Consequently, the sensor exhibits ultra-high sensitivity, with gauge factors of 76.1 (0–30% strain) and 203.5 (30–100% strain), alongside a comfortable user experience. It can detect diverse activities, from subtle physiological signals and joint bending to complex hand gestures and athletic postures. Additionally, the micropatterned composite hydrogel sheet also demonstrates self-healing ability, adhesiveness, and conformability, while performing effectively under extreme temperatures and sweaty conditions. This innovative structure and sensing mechanism—leveraging stress concentration and controlled crack formation—provides a strategy for designing wearable electronics with enhanced performance. Full article

This paper investigates and evaluates a compact, high-Q glass transformer with a 3D spiral structure that offers low loss and high area efficiency. Furthermore, we designed a CMOS power amplifier (PA) with an output-matching network implemented using an off-chip high-Q glass transformer to validate its operation. Two transformer types were developed: a five-port transformer with a center-tap and a four-port transformer without a center tap. The high-Q property of the transformer leads to low loss and tight coupling, as evidenced by an increase in maximum available gain (MAG). Compared with an integrated CMOS transformer, the high-Q transformer exhibits significantly lower loss while maintaining similar area and inductance, despite being an external component. A test PA comprising the CMOS PA and the off-chip transformer was evaluated with simulations and measurements, and it was also compared with a fully integrated PA at the simulation level to verify performance improvements. The proposed PA achieved a saturation power of 29.8 dBm, which was 1.7 dB higher than that of the fully integrated PA. The PAE also improved by 11 percentage points, from 32.1% to 43.1% in simulation. The results show substantial performance gains in simulation, while the total area increases only slightly. Measurements show the same trend as the simulations; with shorter bond-wire lengths, the measured results are expected to approach the simulated performance. These findings demonstrate the feasibility of an ultra-compact CMOS–off-chip hybrid PA that delivers high performance while maintaining a footprint comparable to that of a fully integrated PA, enabling applications in compact devices including mobile products. Full article

In this paper we present a detailed study of bonded knots and their related structures, integrating recent developments into a single framework. Bonded knots are classical knots endowed with embedded bonding arcs modeling physical or chemical bonds. We consider bonded knots in three categories (long, standard, and tight) according to the type of bonds, and in two categories, topological vertex and rigid vertex, according to the allowed isotopy moves, and we define invariants for each category. We then develop the theory of bonded braids, the algebraic counterpart of bonded knots. We define the bonded braid monoid, with its generators and relations, and formulate the analogues of the Alexander and Markov theorems for bonded braids in the form of L-equivalence for bonded braids. Next, we introduce enhanced bonded knots and braids, incorporating two types of bonds (attracting and repelling) corresponding to different interactions. We define the enhanced bonded braid group and show how the bonded braid monoid embeds into this group. These models capture the topology of chains with inter and intra-chain bonds and suggest new invariants for classifying biological macromolecules. Full article

Four different MIL-68(Al) catalysts were synthesized and characterized by XPS, SEM, TEM, XRD, DLS, Nitrogen adsorption removal, and other methods. An aluminum-based MOF (Metal Organic Framework) (MIL-68(Al))/graphite oxide (GO) composite with TiO₂ showed the largest BET specific area with best adsorption performance. Representation demonstrated that MIL-68(Al) and TiO₂ nanoparticles are uniformly dispersed on the surface of the GO lamellar, and a tight heterojunction structure is formed between them. The MIL-68(Al)/GO/TiO₂ exhibits good pore characteristics, structural morphology, and catalytic performance. Adsorption experiments of methyl orange can reach 99.7% with the effect of MIL-68(Al)/GO/TiO₂ in water for 20 min. Moreover, the pH range can be applied to 1–13 and a high concentration of 200 mg/L methyl orange solution also worked well. In addition, this kind of catalyst can also be used for rhodamine B, methylene blue, congo red, and tetracycline in 20 min with good adsorption. Meanwhile, simple filtration can quickly recover MIL-68(Al)/GO/TiO₂ and effectively reuse it. Free radical capture experiments showed a large number of •OH radicals during the adsorption of MO (Methyl Orange) solution by MIL-68(Al)/GO/TiO₂. Meanwhile, the electrostatic interaction, π-π packing and hydrogen bonding make MIL-68(Al)/GO/TiO₂ have a higher adsorption capacity for MO. Therefore, co-doping optimized the structure of MIL-68(Al), enhancing its stability in strong acids and bases while improving adsorption performance across a broader pH range than previously reported. This work addresses the instability of MIL-68(Al) under extreme conditions, demonstrating its significant potential for wastewater treatment applications. Full article

The study of the gas-phase behavior of proteins has recently gained momentum due to numerous prospective applications in, e.g., the construction of molecular sensors or nano-machines. The study of proteins outside their standard water environment, necessary to arrive at their successful applied use, is, however, limited by the loss of the structure and function of the macromolecules in the gas phase. We selected two enzymatic proteins with great potential for applied use, the digestive enzyme trypsin and the cytochrome sterol demethylase, for which to develop gas-phase structural models. The employed levels of theory were semiempirical, density functional tight binding, and polarizable force-field techniques. The convergence of the self-consistent field equations was very slow and in most cases led to oscillatory behavior, encouraging careful tuning of the convergence parameters. The structural optimization and molecular dynamics simulations indicated the parts of the proteins most prone to structural distortion under gas-phase conditions with unscreened electrostatics. This problem was more pronounced for cationic trypsin, for which the stability of the simulation was lower. The fate of the hydrogen bonding network of the catalytic triad in the gas phase was also investigated. Full article

Linear tight-binding models with long-range interactions and small-world geometry have a broad energy spectrum in the nearest neighbor coupling limit, while the spectrum becomes narrow in the fully connected limit due to the emergence of flat bands. A transition to a Wigner-like density of states appears at a low fraction of long-range bonds. Adding nonlinearity to the model introduces correlations among the stationary states, while multiple new states are generated as a result of the nonlinearity. In this work, we study the effect of band correlations on the local density of states for small-world networks as a function of the number of long-range bonds. We find that close to the nearest neighbor limit, the onset of correlations shifts the nonlinear density of states towards the band edge of the spectrum. Close to the opposite limit of the fully connected model, the band collapses in the band center, accompanied by a large increase in the new states induced by the nonlinearity. While in both limits the effect of correlations is to flatten the band, close to the mean field fully connected limit, the states are correlated and generally have distinct localized features. These effects may have implications for the dynamics of electrons in two-dimensional moiré structures and the onset of superconductivity in these systems. Full article

Annealing and rolling play critical roles in improving the mechanical properties of arc spraying coatings. In this work, we successfully fabricated copper–steel bimetallic sheets (CSBSs) using an arc spray-rolling short process and achieved excellent internal bonding of the copper coating and improved deep-drawing of the CSBSs via annealing and rolling synergistic treatment. The results indicate that the microstructure of the copper coating became dense, and the porosity effectively reduced after annealing–rolling–annealing (ARA) treatment. Tight bonding was also observed between the copper coating and steel substrate. The copper coating had a porosity of less than 0.2%, an average grain size of 3.8 μm, and a micro-hardness of 55 HV_0.05. After tensile testing, the As-sprayed coating generated brittle fractures and delamination. The A-R-A coating also displayed elongated dimples, with the majority oriented along the TD direction, and bonded well with the steel substrate. In addition, the As-sprayed coating fell off directly after deep drawing. In contrast, the A-R-A coating did not exhibit cracks and fall off. The fracture mechanism gradually changed from falling off and cracking, to toughness deformation due to the reduced porosity and tighter grain boundaries, and finally to cooperative deformation due to the metallurgical bonding of the sprayed particles and good interface bonding properties. These findings provide guidance and reference for the practical application of thermal spray additive manufacturing. Full article

To meet the growing demand for renewable energy, developing efficient and cost-effective photocatalytic materials is crucial. Specifically, designing photocatalysts with high charge separation efficiency and abundant hydrogen production active sites remains a key challenge for practical applications. In this study, a carbon nitride (g-C₃N₄)-based ternary photocatalyst has been constructed for enhanced photocatalytic H₂ production without the need for precious metal cocatalysts. CoO nanoparticles were loaded onto the surface of g-C₃N₄ via in situ thermal decomposition. Subsequently, a series of g-C₃N₄/CoO/CoP ternary composites were successfully prepared using a direct one-step phosphorization method. Under optimized conditions, the g-C₃N₄/CoO/CoP catalyst exhibits a hydrogen evolution activity of 1277.9 μmol·g⁻¹·h⁻¹, which is 4 times higher than that of g-C₃N₄/CoO (with g-C₃N₄ alone showing no hydrogen evolution activity). Its performance is comparable to that of the commonly used Pt cocatalyst. The performance improvement may be attributed to the tight bonding of N-P bonds, which effectively promotes the transport of photogenerated carriers, while the increased loading of CoP provides more active sites. The results offer a promising strategy for designing efficient and low-cost photocatalytic materials. Full article

Using chitosan and polyvinyl alcohol (PVA) as substrates, active packaging composite (VPC) films based on vanillin-crosslinked PVA/chitosan with different concentrations of added vanillin were prepared and characterized. The results show that the VPC films exhibited higher tightness and hydrophobicity, lower water content and water vapor permeability, as well as better UV resistance. The potential interactions between the film groups were analyzed by SEM, FTIR, and XRD, and the results showed that the formation of Schiff base and hydrogen bond interactions affected the properties of the films. The VPC films also showed excellent antioxidant activity. Therefore, vanillin-crosslinked PVA/chitosan active films have broader application prospects as packaging materials for food preservation. Full article

The main protease (M^pro or 3CL^pro or nsp5) of SARS-CoV-2 is crucial to the life cycle and pathogenesis of SARS-CoV-2, making it an attractive drug target to develop antivirals. This study employed the virtual screening of a few phytochemicals, and the resultant best compound, Scopoletin, was further investigated by a FRET-based enzymatic assay, revealing an experimental IC₅₀ of 15.75 µM. The impact of Scopoletin on M^pro was further investigated by biophysical and MD simulation studies. Fluorescence spectroscopy identified a strong binding constant of 3.17 × 10⁴ M⁻¹ for Scopoletin binding to M^pro, as demonstrated by its effective fluorescence quenching of M^pro. Additionally, CD spectroscopy showed a significant reduction in the helical content of M^pro upon interaction with Scopoletin. The findings of thermodynamic measurements using isothermal titration calorimetry (ITC) supported the spectroscopic data, indicating a tight binding of Scopoletin to M^pro with a K_A of 2.36 × 10³ M⁻¹. Similarly, interaction studies have also revealed that Scopoletin forms hydrogen bonds with the amino acids nearest to the active site, and this has been further supported by molecular dynamics simulation studies. These findings indicate that Scopoletin may be developed as a potential antiviral treatment for SARS-CoV-2 by targeting M^pro. Full article

A novel composite cementitious material was constructed by synergistically utilizing multiple industrial solid wastes, including electrolytic manganese residue (EMR), red mud (RM), and ground granulated blast furnace slag (GGBS), with calcium hydroxide [Ca(OH)₂] as an alkaline activator. In addition, the mechanical properties of the composite cementitious materials were systematically analyzed under different raw material ratios, alkali activator dosages, and water-binder ratios. To further investigate the hydration products and mechanisms of the composite cementitious material, characterization methods, for instance, XRD, FT-IR, SEM-EDS, and TG-DTG, were employed to characterize the materials. To ensure that the composite cementitious material does not cause additional environmental pressure, it was analyzed for toxic leaching. The relevant experimental results indicate that the optimal ratio of the EMR–RM–GGBS–Ca(OH)₂ components of the composite cementitious material is EMR content of 20%, RM content of 15%, GGBS content of 52%, calcium hydroxide as alkali activator content of 13%, and water-binder ratio of 0.5. Under the optimal ratio, the composite cementitious material at 28 days exhibited a compressive strength of 27.9 MPa, as well as a flexural strength of 7.5 MPa. The hydration products in the as-synthesized composite cementitious material system primarily encompassed ettringite (AFt) and hydrated calcium silicate (C-S-H), and their tight bonding in the middle and later curing stages was the main source of engineering mechanical strength. The heavy metal concentrations in the 28-day leaching solution of the EMR–RM–GGBS–Ca(OH)₂ composite cementitious material fall within the limits prescribed by the drinking water hygiene standard (GB5749-2022), indicating that this composite material exhibits satisfactory safety performance. To sum up, it is elucidated that the novel process involved in this research provide useful references for the pollution-free treatment and resource utilization of solid wastes such as red mud and electrolytic manganese residue in the future. Full article

The widespread implementation of new CAD/CAM materials has led to the necessity of establishing an adequate luting protocol. The aim of this study was to evaluate the microtensile bond strength (μTBS) and the film thickness of different luting methods on CAD/CAM resin blocks. Five Brilliant Crios CAD/CAM blocks (Coltene/Whaledent) were sequentially sectioned into two halves, air abraded with 50 µm aluminum oxide, and luted according to five different cementation protocols: Brilliant EverGlow (BEG), Brilliant EverGlow with ultrasound application (BEG-US), preheated Brilliant EverGlow (BEG-H), Brilliant EverGlow Flow (BEGF), and Duo Cem^® Trans (DC). Subsequently, the blocks were sectioned to obtain rods, which were then submitted to a microtensile bond strength test (n = 20). The surfaces were examined with optical microscopy to determine the failure mode and the bonding interface was assessed with scanning electron microscope (SEM) analysis. Bond strength values were analyzed using one-way ANOVA and Tukey’s post hoc tests (α = 0.05). The bond strength values varied with the different cementation protocols (p < 0.001): BEG (45.48 ± 18.14 MPa), BEG-US (42.15 ± 14.90 MPa), BEG-H (41.23 ± 15.15 MPa), BEGF (58.38 ± 15.65 MPa), and DC (81.07 ± 8.75 MPa). Regarding bond strength, DC presented significantly higher values than all other experimental groups (p < 0.050), whereas all luting methods using BEG presented similar values (p = 0.894). Adhesive failures were the predominant type. On SEM evaluation, all the luting materials presented a tight and homogeneous cement–block interface with variable film thicknesses. In conclusion, among the cementation protocols, the resin cement (DC) rendered the highest bond strength values. SEM analysis revealed that the lowest film thickness was associated with the flowable composite (BEGF). Full article