Search Results (261)

Chronic wounds are complex environments marked by persistent inflammation, oxidative stress, hypoxia, and conditions that favor antimicrobial resistance (AMR). Conventional antibiotics often fail due to bacterial persistence and the physicochemical barriers of the wound milieu. Biofilm-associated extracellular polymeric substances (EPS), efflux pump activity, quorum sensing (QS), and horizontal gene transfer (HGT) collectively drive antimicrobial tolerance and resistance dissemination, turning chronic wounds into reservoirs of multidrug-resistant pathogens. Consequently, emerging wound therapies demand multifunctional strategies that modulate the wound microenvironment while interfering with resistance-associated phenotypes. Hydrogel–metal–organic framework (MOF) composites have been explored as multifunctional interfaces that combine extracellular matrix-mimetic properties, tunable porosity, stimuli-responsiveness, and controlled therapeutic delivery with the bioactive functions of MOFs. Depending on their composition and architecture, these systems may exert antimicrobial and antibiofilm effects through ionic, electrostatic, osmotic, catalytic, and oxidative mechanisms, while also influencing ROS levels, inflammation, angiogenesis, and local drug transport. However, antimicrobial activity alone does not equate to resistance modulation. Evidence for direct effects on efflux systems, resistance phenotypes, or HGT remains inconsistent across reported platforms. This review critically examines representative hydrogel–MOF systems for chronic wound applications, comparing their composition, physicochemical properties, biological functions, proposed resistance-related mechanisms, advantages, limitations, and current level of evidence. We emphasize distinguishing experimentally demonstrated resistance-modulating effects from mechanistically proposed functions, and identifying design trade-offs and evidence gaps that must be addressed to develop wound interfaces capable of both supporting tissue regeneration and improving infection control. Full article

To address the challenge that microelectromechanical system (MEMS) gyroscope electrostatic force-modulated closed-loop self-excited driving circuits experience significant dynamic variations in capacitive load and driving demand under different operating conditions, such as start-up, steady-state resonance maintenance, and environmental perturbations, making it difficult to simultaneously achieve strong driving capability, stable oscillation, and low power consumption, this paper proposes a high-energy-efficiency adaptive output operational amplifier architecture. Based on a dynamic load-sensing mechanism, the design introduces a three-threshold decision scheme combining a high threshold, a low threshold, and a mid-supply reference voltage. By coordinating a continuous-time voltage detection circuit with a bidirectional shift register, the proposed approach enables accurate identification of the output state and the load level. A time-division-multiplexed two-stage control strategy is adopted to rapidly compensate for the drive capability under abrupt load changes, while proactively disabling redundant output units under steady-state conditions, thereby achieving power delivery on demand. The output stage employs a Class-AB push–pull structure integrating an improved low-leakage single-pole double-throw (SPDT) switch, which hard shuts off the power transistors in the non-operating state to effectively eliminate the subthreshold leakage current. Circuit simulations in a 0.18 μm CMOS process demonstrate that the proposed operational amplifier can adaptively regulate its output current in real time according to variations in the gyroscope driving demand, ensuring sufficient an electrostatic driving force and oscillation stability during transient conditions while significantly reducing static power consumption during the resonance steady state. The proposed design provides an effective solution for high-performance and high-energy-efficiency interface circuit design in MEMS gyroscope electrostatic force-modulated closed-loop self-excited driving systems. Full article

Epidermal growth factor receptor (EGFR) mutations drive hepatocellular carcinoma (HCC) progression, and the T790M gatekeeper substitution is the predominant mechanism of acquired resistance to EGFR-targeted therapies. Herein, we present multiscale quantum-classical in silico predictions of Phyllanthus niruri phytochemicals as non-covalent EGFR T790M binders, employing molecular docking, 100 ns molecular dynamics, MM-PBSA/MM-GBSA, per-residue decomposition, PCA/LDA, DFT at B3LYP-D3(BJ)/def2-TZVP, and comparative wild-type EGFR simulations. Five phytochemicals exhibited computationally predicted binding affinities against EGFR T790M exceeding the non-covalent binding component of osimertinib (−25.74 kcal/mol): corilagin (−53.71 ± 5.05 kcal/mol), eriodictyol-7-rhamnopyranoside (−44.35 ± 4.51 kcal/mol), isoquercetin (−44.23 ± 2.92 kcal/mol), rutin (−42.15 ± 4.50 kcal/mol), and kaempferol-4-rhamnoside (−41.68 ± 3.69 kcal/mol). Wild-type EGFR simulations (PDB 1M17) yielded a selectivity index (IS) of 2.76 for corilagin (ΔΔG_bind = +34.22 kcal/mol), indicating T790M-preferential binding. Osimertinib reproduced its clinically established T790M selectivity under identical conditions (IS = 1.43; ΔΔG_bind = +7.74 kcal/mol), providing internal methodological validation. DFT at B3LYP-D3(BJ)/def2-TZVP established the quantum-mechanical basis for corilagin’s electrostatic affinity: its molecular electrostatic potential (MEP) surface minimum (V_s,min = −46.92 kcal/mol) directly predicts the largest MM-PBSA electrostatic term (ΔE_ele = −52.48 kcal/mol), establishing quantum-classical coherence. Supervised PCA/LDA of 7416 MM-PBSA trajectory frames identified solvation energy (ΔG_SOLV) as the primary pharmacological class discriminant, with the first discriminant function (LD1) capturing 93.1% of inter-class binding variance. Collectively, corilagin (hydrolyzable tannin), eriodictyol-7-rhamnopyranoside (flavonoid glycoside), and phyltetralin (lignan) constitute diverse computational leads from P. niruri warranting experimental validation as T790M-directed agents in HCC. Full article

Electrohydrodynamic (EHD) actuators offer a promising approach for active particulate matter (PM) control in heavy-duty and marine exhaust systems. However, continuous DC corona discharge often leads to excessive energy consumption and is susceptible to aerodynamic re-entrainment in high-velocity flows. This study introduces an idealized transient advection mechanism combining a macroscopic corrugated duct geometry with high-frequency pulsed EHD actuation. A fully coupled, time-dependent multiphysics model—integrating RANS turbulent flow, Poisson-Nernst-Planck space charge transport, and Lagrangian discrete particle tracing—was developed to analyze the physical kinetics of 0.2 µm soot particles. The results demonstrate that the corrugation troughs act as effective aerodynamic dead zones with partial electrostatic shielding, creating aerodynamic and electrostatic dead zones. During active microsecond voltage pulses (25 kV peak), intense Coulombic forces rapidly overcome turbulent drag, driving kinetic injection of particles into the corrugation troughs. During the resting phase, particles remain securely trapped by aerodynamic shielding, significantly mitigating the risk of aerodynamic re-entrainment under the simulated conditions. A comprehensive parametric analysis revealed that an optimized 500 Hz pulse with a 5% duty cycle maintains a robust 82.7% trapping efficiency. Compared to standard continuous DC precipitators, this pulsed actuation strategy requires an idealized active corona power of 15.3 mW. This study provides fundamental physical insights into transient EHD flows and establishes optimized design criteria for fundamental EHD transport models. Full article

Colloidal crystals permeated by mobile ions exhibit a coupling between electrostatic and elastic degrees of freedom that renormalizes the effective screening length and induces wave-vector-dependent elastic softening. Building on our recently proposed continuum model, we perform a rigorous Gaussian fluctuation analysis to elucidate the stability limits of the homogeneous phase. By integrating out the electrostatic fluctuations, we derive the effective elastic modulus $\Gamma \left(q\right)$ as a function of wave vector q. We show that the modulus in the long-wavelength limit ($q\to 0$) remains identically equal to a bare modulus protected by perfect ionic screening. In contrast, the modulus in the short-wavelength limit ($q\to \infty$) softens as the electrostatic-elastic coupling strength $\xi$ increases, vanishing at a critical value $\xi =1$. For $\xi >1$, the fluctuation spectrum exhibits a negative eigenvalue for all wave vectors q larger than a critical (effective screening) wave vector $q_c$, signaling an ultraviolet instability of the uniform phase. In a real colloidal crystal, this divergence is regulated by the discrete lattice cutoff $q_{\max }\sim \pi /a$, confining the physical instability to a finite band $q_c<q<q_{\max }$. The macroscopic limit $q\to 0$ remains unconditionally stable for all $\xi$. The transition at $\xi =1$ thus marks the onset of short-wavelength mechanical failure, while macroscopic elastic stiffness remains intact. Our analysis clarifies the proper physical interpretation of the minimal coupling model and provides a consistent picture of how non-DLVO interactions can drive local structural collapse in charged colloidal crystals. Full article

Finding cost-effective and eco-friendly ways to remove toxic heavy metals from wastewater remains a critical challenge for industrial sustainability. This study presents a comparative performance matrix of coal fly ash (CFA) and bone charcoal (BC) for the high-capacity remediation of Cd(II) and Pb(II) ions. This work establishes a direct cross-matrix comparison between a heterogeneous aluminosilicate phase (CFA) and a uniform calcium-phosphate structure (BC) under identical systemic boundaries. SEM/EDS, FT-IR, and complementary TG/DTG/DTA screenings confirmed that distinct material-specific functional frameworks drive a predominantly physical mechanism governed by electrostatic and van der Waals interactions. Equilibrium data fitted the non-linear Langmuir model well (R² > 0.99 at 20 °C). BC proved to be significantly more effective, achieving maximum sorption capacities (q_max of 397.55 mg/g for Pb(II) and 325.09 mg/g for Cd(II), outperforming CFA (118.22 and 105.59 mg/g, respectively). Sorption capacities decreased with temperature up to 80 °C, confirming the exothermic nature of the process, which was further substantiated by negative enthalpy values (∆H⁰ = −7.27 to −14.19 kJ/mol). Thermodynamic parameters indicated a spontaneous process (∆G⁰ < 0, −9.55 to −19.33 kJ/mol) with positive entropy changes (∆S⁰ = 5.82 to 39.09 J/(mol·K)). Adsorption kinetics followed the pseudo-second-order model, with intraparticle diffusion acting as a key rate-limiting step. Regardless of the adsorbent, Pb(II) ions were immobilized faster and more efficiently than Cd(II) due to a smaller hydration radius. In conclusion, both industrial by-products represent promising, sustainable options for heavy metal wastewater treatment, with BC demonstrating superior performance. Full article

To enhance quantitativeness and interpretability in identifying the mechanisms of complex oil–mineral–surfactant systems, this paper introduces an algorithmic molecular simulation analysis approach, transforming molecular dynamics trajectory data into comparable multidimensional molecular descriptors. Specifically, based on parameters such as radial distribution functions, mean square displacement, interface concentration distribution, adsorption energy attenuation, hydrogen bond statistics, and electrostatic interactions, an algorithm analysis framework was constructed covering “trajectory data acquisition—feature descriptor extraction—interface behavior recognition—separation mechanism classification.” This framework can identify differentiated regulatory patterns of different surfactants on SARA (saturates, aromatics, resins, asphaltenes) component migration, adsorption, and desorption behavior from a large amount of dynamic simulation data, thereby improving the structural expression and mechanism discrimination capabilities of molecular simulation results. In order to clarify the component-selective microscopic mechanisms of surfactants in the separation of heavy oil from oil sands, this work employs molecular dynamics simulations to study the interactions of the non-ionic surfactant TX-100 and the biosurfactants sophorolipid and rhamnolipid with the SARA fractions of heavy oil, both in the absence and presence of calcite mineral surfaces. The results show that all three surfactants act mainly through weak long-range interactions, but with distinct mechanisms: TX-100 preferentially screens small-molecule saturates through long-chain steric hindrance and hinders the diffusion of asphaltenes; sophorolipid promotes the preferential desorption of resins via hydrogen bonding; and rhamnolipid drives the desorption of aromatics at later stages through hydrophobic–electrostatic synergy. The C001 crystal surface exhibits the strongest adsorption affinity across all systems; the mineral surface overall prolongs the diffusion equilibrium time and amplifies the above kinetic differences. This study establishes three molecular-scale mechanisms—steric hindrance sieving, hydrogen-bond-promoted desorption, and electrostatically driven desorption—and reveals the universal adsorption platform effect of the C001 crystal surface, providing a theoretical basis for the molecular design of surfactants aimed at the selective separation of heavy oil components. Full article

Traditional macroscopic interfacial theory cannot fully explain the anomalous stability of nanobubbles, which limits their use in micro/nano interfacial engineering. In this study, molecular dynamics simulations were used to systematically investigate the evolution of oxygen nanobubbles with diameters of 3, 5, and 8 nm in water. The results show a clear size effect in bubble structural evolution: the 3 nm bubble had the largest motion radius, about 3.5 nm, which was 40% and 133% larger than those of the 5 and 8 nm bubbles, respectively. At the nanoscale, surface tension still provides a basic constraint, but its value is lower than the classical theoretical prediction, with a deviation of 35.7% for the 3 nm bubble, indicating that it is not the sole dominant stabilizing force. Water molecules at the gas–liquid interface experienced a net force of 371.92–421.56 pN, with 60–65% directed toward the bubble interior, forming an asymmetric force field that cooperates with surface tension to maintain bubble stability. This force field further drives directional polarization of water molecules and induces a dense hydrogen-bond network: stronger charge parameters correspond to denser hydrogen bonding, with the peak net charge of Charge4 being 37.5 times that of Charge1 and the hydrogen-bond number being 11.6 times that of Charge2. The dense hydrogen-bond network is quantitatively associated with restricted interfacial water mobility. The interfacial potential energy decreases, with an 8 nm bubble showing a reduction of 0.31 kcal/mol, and the U–T coupling energy exhibits a clear interfacial peak of 36–66 kcal/mol. Further analysis shows that the apparent diffusion coefficient decreases nearly exponentially with the maximum hydrogen-bond number, and the water MSD decreases markedly as hydrogen bonding increases, with the MSD of Charge1 being 1303 times that of Charge4. These results indicate that enhanced interfacial electrostatic force, densification of the hydrogen-bond network, and restricted interfacial water mobility jointly increase structural constraints at the gas–liquid interface and suggest a possible increase in gas-transfer resistance across the interface. This study clarifies, at the molecular scale, a physical picture in which surface tension, electrostatic force, hydrogen-bond densification, energy stabilization, and restricted mobility jointly maintain nanobubble stability. Full article

Haze Pollution in China arises from the rapid enlargement of ultrafine particles into light-absorbing fine particulate matter through adsorption processes under atmospheric stagnation conditions. This study focuses on the sources of ultrafine particles (UFPs), the most critical component of haze pollutants during severe pollution periods in China. Utilizing methods including the spatial Durbin model and statistical data for the 28 cities (the “2 + 26” cities) within the Beijing–Tianjin–Hebei air pollution transmission channel—suffering the most severe haze pollution—it investigates the impact of pollution-intensive industries on haze pollution. This study reveals several key findings regarding China’s haze pollution. First, the principal source of ultrafine particles within China’s haze stems from the desulfurization, denitrification, and dust removal processes of pollution-intensive industries (the direct effect of these industries on haze is 0.028 * according to the SDM regression results). Crucially, the specific operational factors driving the abrupt increase in atmospheric UFPs during severe haze periods in China are identified as extensive management practices in desulfurization, the progressive tightening and annual escalation of denitrification emission standards, and the reliance on electrostatic precipitation which is ineffective against ultrafine particles. Second, haze pollution predominantly occurs in regions characterized by concentrations of pollution-intensive industries coupled with weak atmospheric environmental self-purification capacity (this carrying capacity for pollution-intensive industries exerts a significant negative impact on haze, demonstrated by a direct effect of −0.020 **; further analysis reveals that this is caused by regional differences in atmospheric self-purification capacity). Third, regional air transport acts as a contributing source, introducing UFPs from neighboring areas into local haze pollution, reflected by an indirect effect of pollution-intensive industries of 0.151 ** stemming from such spatial spillovers. Based on these conclusions, the study proposes a set of policy recommendations: relocate pollution-intensive industries using a gradient approach based on atmospheric self-purification capacity differences; systematically upgrade wet flue gas desulfurization technologies for industrial emissions; effectively promote technological innovation in denitrification processes; implement scientific controls on ammonia emissions; strengthen R&D in core technologies for UFP removal; innovate dust removal technologies to enhance overall system efficiency; reinforce regional coordinated governance; implement targeted training programs and select qualified management personnel; systematically enhance the environmental management capabilities of staff; and effectively mitigate the spillover effects of haze pollution. Full article

Sulfachloropyridazine (SCP) is a sulfonamide antibiotic widely detected in aquatic environments. Its terminal pyridazine ring contains vicinal pyridinic nitrogen atoms (=N–N=) with strong metal-complexing ability, which may cause distinct interactions with metal-oxide filter media. Here, we systematically investigated the removal of sulfonamide antibiotics by natural manganese sand (NMS), a representative filtration medium in water treatment. NMS exhibited pronounced selectivity toward SCP, while showing negligible removal of sulfadiazine (SD) and sulfamethoxazole (SMX). Under optimal conditions (NMS = 5 g·L⁻¹, pH 3), 99.38% of SCP (5 mg·L⁻¹) was removed within 6 h; the TOC reduction only reached 42.65%, suggesting the partial transformation of SCP. Mechanistic evidence suggests that the vicinal pyridinic N–N motif of SCP provides dual electron-donating sites, enabling inner-sphere Mn–N complexation on NMS. This coordination-driven adsorption is strongly pH-dependent and is inhibited under neutral to alkaline conditions (pH > 5) due to electrostatic repulsion. After selective binding, surface Mn(III)/Mn(IV) species can act as electron acceptors, driving the surface oxidation of SCP. Although NMS induced mild oxidative transformation of SCP, some degradation products still exhibited potential ecotoxicity and therefore require further attention in practical water treatment applications. These findings link terminal functional-group structure to selective abiotic removal on Mn-oxide media and inform targeted control of sulfonamide micropollutants in filtration-based water treatment. Full article

This article introduces the current status of the 0.18-micron CMOS MEMS foundry service platform provided by the Taiwan Semiconductor Research Institute (TSRI), extensively covering the CMOS MEMS components that it has supported in development and fabrication. It also attempts to expand the foundry service scope to the broader categories of capacitive sensors and electrostatic actuators. On the one hand, for fabless MEMS component designers, TSRI currently directly allows the design of two types of components: flow sensors with uniformly perforated membranes and actuators with comb-shaped interdigital electrodes. This service also includes tape-out and wire bonding packaging procedures, following procedures similar to those used by general IC designers. On the other hand, this article specifically presents a clear and feasible approach for MEMS designers equipped with simple wet-etching facilities and a clear and feasible approach to develop further CMOS MEMS components such as capacitive pressure sensors, accelerometers, micro mirrors, and scratch drive actuators with minimal post-processing and chip packaging steps. This work provides a practical CMOS-MEMS design and post-processing guideline for extending the current TSRI foundry platform toward capacitive sensing and electrostatic actuation applications with minimal additional fabrication complexity. Full article

Addressing the urgent demand for high-precision pressure measurement in real-time barometric monitoring, aerospace, and industrial control, this paper presents a high-accuracy MEMS resonant pressure sensor based on electrostatic excitation and piezoresistive detection. The sensor incorporates a symmetric double-ended fixed-finger comb-drive resonator structure, driven into stable vibration at its natural frequency by an alternating electrostatic force. Piezoresistors integrated at the root of the resonant beams transduce the mechanical vibration into a frequency output, enabling precise external pressure measurement. Experimental results show that the developed sensor achieves an accuracy of 0.009% FS over a pressure range of 0–350 kPa across an operating temperature span from −30 °C to 50 °C, with a room-temperature repeatability error below 0.008% FS, demonstrating excellent measurement stability. Building on this performance, a real-time atmospheric pressure monitoring experiment was conducted, yielding a mean absolute percentage error of less than 0.05%, highlighting the sensor’s potential for engineering practicality. This work provides an effective technique for a high-precision, high-stability resonant pressure sensor, with clear potential for deployment in real-time barometric monitoring, aerospace, and industrial control applications. Full article

Nanotextured thin film metallic glasses (TFMGs) have emerged as promising antimicrobial coatings for biomedical applications; however, systematic comparisons across compositionally distinct Ti- and Zr-based systems, as well as their early-stage bactericidal mechanisms, remain limited. Here, we show, for the first time, a comparative, compositionally resolved correlation linking alloy chemistry, nanotexture, and bactericidal mechanisms across polymorphic TFMGs. Three co-sputtered biocompatible coatings (Ti₄₇Fe₄₁Cu₁₂, Zr₇₁Fe₃Al₂₆, and Zr₅₈W₃₁Cu₁₁) were deposited on medical-grade titanium and stainless steel (SS316L) via magnetron co-sputtering, producing uniform amorphous films (190–298 nm) with nanoscale roughness of 1.6 ± 0.05 to 8.1 ± 0.05 nm. Surface wettability spanned hydrophilic (71.1 ± 5.6°) to hydrophobic (106.5 ± 3.5°), modulating bacterial interactions. Antimicrobial performance against Pseudomonas aeruginosa was evaluated using live/dead fluorescence imaging, quantitative image analysis, and electron microscopy after 2–4 h incubation. All coatings reduced bacterial adhesion and viability relative to bare substrates, with Zr₅₈W₃₁Cu₁₁ achieving >60% reduction in surface-associated bacterial coverage. Time-resolved analysis revealed a rapid transition to predominantly non-viable populations on coated surfaces, in contrast to sustained viability on controls. Mechanistically, bactericidal activity arises from the synergistic coupling of nanotopography-induced membrane stress, wettability-governed adhesion energetics, and in situ formation of CuO, Fe₂O₃, WO₃, and ZrO₂ oxides that promote electrostatic interactions and proposed reactive oxygen species generation, driving oxidative membrane damage. These results establish a scalable design framework for TFMGs, while highlighting the need for long-term biofilm and electrochemical validation. Full article

The increasing emission of harmful gases into the atmosphere represents a major environmental challenge, driving the need for efficient air purification materials. Poly(methyl methacrylate) (PMMA) has emerged as a promising candidate due to its favorable physicochemical properties and adsorption potential. In this study, the interactions between PMMA and selected sulfur-containing pollutants (CH₃SH, COS, CS₂, H₂S, and SO₂) were systematically investigated using a multiscale computational approach. Initial structural exploration was performed using extended tight-binding (xTB) methods, followed by refinement at the density functional theory (DFT) level, while molecular dynamics (MD) simulations were employed to capture the dynamic behavior of the systems. The results suggest that all investigated gases exhibit attractive interactions with PMMA, with interaction strength strongly dependent on molecular polarity and electronic structure. Among the studied systems, SO₂ shows the strongest binding, while CS₂ exhibits the weakest interaction. Energy decomposition based on symmetry-adapted perturbation theory (SAPT) and electronic structure analyses suggest that electrostatic and donor–acceptor interactions play a dominant role for strongly interacting systems, whereas weaker interactions are primarily governed by dispersion forces. Full article

In this study, a polyvinyl alcohol/carboxymethyl chitosan (PVA/CCTS) hydrogel was synthesized via free radical polymerization and employed for the adsorption of Rhodamine B (RhB) from aqueous solution. The hydrogel was systematically characterized by FTIR, SEM, XPS, and BET analyses, confirming its interconnected porous network and functional group composition. Under optimized conditions (adsorbent dosage = 0.1 g, pH = 6, RhB concentration = 65 mg·L⁻¹, and T = 298.15 ± 2 K), the maximum adsorption capacity reached 15.88 mg·g⁻¹. Kinetic analysis showed that the pseudo-second-order model best described the adsorption behavior under optimal conditions, indicating that the uptake of RhB is governed by multiple interaction mechanisms rather than simple physisorption alone. The equilibrium data were best fitted by the Freundlich isotherm (R² = 0.976), indicating surface heterogeneity of the hydrogel. Thermodynamic evaluation revealed an endothermic (ΔH = 28.38 ± 4.40 kJ·mol⁻¹), with adsorption efficiency improving at elevated temperatures. The hydrogel retained appreciable adsorption capacity after three adsorption–desorption cycles (5.78 mg·g⁻¹ at the third cycle). Density functional theory (DFT) calculations identified -COOH and -NH₂ groups as the primary active sites, and molecular electrostatic potential analysis confirmed that electrostatic interactions between the negatively charged hydrogel surface and cationic RhB drive the initial adsorption. Molecular dynamics (MD) simulations over 100 ns further demonstrated that van der Waals forces constitute the dominant driving force, supplemented by electrostatic interactions and hydrogen bonding, with the hydrogel’s cross-linked network stabilizing adsorbed RhB molecules. The integrated experimental computational approach provides a comprehensive mechanistic understanding of RhB adsorption on PVA/CCTS hydrogel, offering guidance for the rational design of polysaccharide-based adsorbents for dye-contaminated wastewater treatment. Full article