BINA

In this work, we elucidate the crucial role of borate anions ([B(OH)4]-) for the electrocatalytic urea oxidation reaction (UOR) using a nanoporous metallic nickel (NP-Ni) catalyst grown on Si substrates. The UOR activity of the NP-Ni catalyst has been studied at various boric acid (H3BO3) concentrations, demonstrating superior activity at a specific electrolytic composition of 0.5 M KOH, 0.33 M urea, and 50 mM of H3BO3. Based on a wide range of electrochemical techniques, such as, cyclic voltammetry (CV), linear sweep voltammetry (LSV), Pb-anodic deposition, and chronoamperometry (CA), we develop a potential mechanism for the [B(OH)4]--mediated UOR. The high double layer capacitance, surface density of Ni redox sites, and urea oxidation currents, clearly demonstrate the significant impact of [B(OH)4]- during electrolysis. Furthermore, we find that UOR catalyzed by the NP-Ni is controlled by diffusion both in presence and absence of [B(OH)4]-. Finally, a set of physical characterizations, including XPS, SEM, and TEM were performed to correlate the composition and structure of the NP-Ni to the [B(OH)4]--mediated increased UOR activity. The boosted UOR we obtain can open new avenues for treatment of wastewater and assist with environmental remediation.

Rechargeable Zn-air batteries with near-neutral electrolytes hold promise as cheap, safe and sustainable devices, but they suffer from slow charge kinetics and remain poorly studied. Here we reveal a charge storage mechanism of near-neutral Zn-air batteries that is mediated by H2O2 formation upon cell discharge and its oxidation upon charge. The manifestation of this mechanism strongly depends on the electrolyte composition and positive electrode material, being pronounced when ZnSO4 solutions and carbon nanotubes are employed. Oxidation of dissolved H2O2 is facile, enabling oxygen evolution reaction (OER) at low potentials (~1.5 V vs. Zn2+/Zn) which, in contrast to conventional four-electron OER, does not induce corrosion of carbon electrodes. Facilitation of the H2O2-mediated pathway might therefore be helpful for developing high-performance near-neutral Zn-air batteries.

We investigate a system of Brownian particles weakly bound by attractive parity-symmetric potentials that grow at large distances as , with . The probability density function at long times reaches the Boltzmann-Gibbs equilibrium state, with all moments finite. However, the system's relaxation is not exponential, as is usual for a confining system with a well-defined equilibrium, but instead follows a stretched exponential with exponent . This problem is studied from three perspectives. First, we propose a straightforward and general scaling rate-function solution for . This rate-function, which is an important tool from large deviation theory, also displays anomalous time scaling and a dynamical phase transition. Second, through the eigenfunctions of the Fokker-Planck operator, we obtain, using the WKB method, more complete solutions that reproduce the rate function approach. Finally, we show how the alternative path-integral formalism allows us to recover the same results, with the above rate-function being the solution of the classical Hamilton-Jacobi equation describing the most probable path. Properties such as parity, the role of initial conditions, and the dynamical phase transition are thoroughly studied in all three approaches.

Enzymes play crucial roles in all biological systems by catalyzing a myriad of chemical reactions. These reactions range from simple one-step processes to intricate multistep cascades. Predicting mechanistically appropriate binding modes along a reaction pathway for substrate, product, and all reaction intermediates and transition states is a daunting task. To address this challenge, special docking programs like EnzyDock have been developed. Yet, running such docking simulations is complicated due to the nature of multistep enzyme processes. This work presents CHARMM-GUI EnzyDocker, a web-based cyberinfrastructure designed to streamline the preparation and running of EnzyDock docking simulations. The development of EnzyDocker has been achieved through integration of existing CHARMM-GUI modules, such as PDB Reader and Manipulator, Ligand Designer, and QM/MM Interfacer. In addition …

High-performance water-based inkjet inks are critical for advancing inkjet printing technology. The performance of water-based inkjet inks depends largely on the dispersion stability of organic pigments. This imposes higher demands on the performance of polymeric dispersants. However, the relatively weak interaction between polymeric dispersants and organic pigments limits their performance in water-based inkjet inks. Consequently, it is crucial to seek dispersants that exhibit stronger interactions with pigments, alongside high performance, and universality. In this work, five types of polymeric nanoparticles (PNPs) with anion-π groups were synthesized via a simple emulsion polymerization method. Compared to traditional polymeric dispersants, anion-π type PNPs exhibited significant advantages including low viscosity, solvent resistance, and high temperature resistance. Stronger interactions, including salt-bridge hydrogen bondings (H-bonds) and π–π interactions, between these PNPs and different types of organic pigments were demonstrated by FTIR, UV-Vis, and XPS spectral tests. In particular, PNPs-5, bearing -PhSO3− groups, exhibited the strongest interaction with the organic pigments. The water-based inkjet inks, formulated with PNPs-5 serving as a dispersant, exhibited remarkable dispersion stability and outstanding weatherability. This work rationally constructs a strategy for preparing universally applicable polymeric dispersants to enhance the dispersion of pigments in water-based inkjet inks, thereby presenting a broader perspective for applications in the field of inkjet printing.

Identifying orbital textures and their effects on the electronic properties of quantum materials is a critical element in developing orbitronic devices. However, orbital effects are often entangled with the spin degree of freedom, making it difficult to uniquely identify them in charge transport phenomena. Here, we present a combination of scanning superconducting quantum interference device (SQUID) current imaging, global transport measurements, and theoretical analysis, that reveals a direct contribution of orbital textures to the linear charge transport of 2D systems. Specifically, we show that in the LaAlO/SrTiO interface, which lacks both rotation and inversion symmetries, an anisotropic orbital Rashba coupling leads to conductivity anisotropy in zero magnetic field. We experimentally demonstrate this result by locally measuring the conductivity anisotropy, and correlating its appearance to the non-linear Hall effect, showing that the two phenomena have a common origin. Our results lay the foundations for an all--electrical probing of orbital currents in two-dimensional systems.

Arterial oxygen saturation (SpO2), a key indicator of respiratory health, reflects the proportion of oxygenated hemoglobin in the blood and is essential for monitoring conditions such as hypoxia. Traditional pulse oximetry methods use multiple wavelengths to calculate SpO2, which cause errors due to differences in optical pathlengths, affected by different scattering coefficients. This study presents an optical biosensor for non-invasive measurement of SpO2, utilizing the iso-pathlength (IPL) point concept. Our biosensor overcomes the inherent limitations of the classic method by using a single light source and detecting reemitted light at the IPL point, where light intensity is invariant to scattering. This enables accurate SpO2 measurements without the need for external calibration. The biosensor operates with a red LED at 655nm and five photodetectors, one positioned at the IPL point, which allows the extraction of …

Photoluminescence of non-aromatic supramolecular chemical assemblies has attracted considerable attention in recent years due to its potential for use in molecular sensing and imaging technologies. The underlying structural origins, the mechanisms of light emission in these systems, and the generality of this phenomenon remain elusive. Here, we demonstrate that crystals of L-Cysteine (Cys) formed in heavy water () exhibit distinct packing and hydrogen-bond networks, resulting in significantly enhanced photoluminescence compared to those prepared in . Using advanced excited-state simulations, we elucidate the nature of electronic transitions that activate vibrational modes of Cys in , particularly those involving thiol (S-H) and amine (C-N) groups, which lead to non-radiative decay. For the crystal formed in , these modes appear to be more constrained, and we also observe intersystem crossing from the singlet to the triplet state, indicating a potentially more complex light emission mechanism. Our findings provide new insights into this intriguing phenomenon and introduce innovative design principles for generating emergent fluorophores.

Machine learning (ML) has shown great potential in the adaptive immune receptor repertoire (AIRR) field. However, there is a lack of large-scale ground-truth experimental AIRR data suitable for AIRR-ML-based disease diagnostics and therapeutics discovery. Simulated ground-truth AIRR data are required to complement the development and benchmarking of robust and interpretable AIRR-ML methods where experimental data is currently inaccessible or insufficient. The challenge for simulated data to be useful is incorporating key features observed in experimental repertoires. These features, such as antigen or disease-associated immune information, cause AIRR-ML problems to be challenging. Here, we introduce LIgO, a software suite, which simulates AIRR data for the development and benchmarking of AIRR-ML methods. LIgO incorporates different types of immune information both on the receptor and …

This paper presents an extension of time multiplexing super-resolution imaging concept to allow imaging through scattering medium. The presented concept includes laser illuminating an object through a diffuser. The technique performs time multiplexing super-resolved imaging through this diffuser while using the unknown speckle pattern the diffuser projects on the imaged object to enhance the resolution at which the object is imaged. Thus, unlike in conventional case where imaging through a diffuser or other scattering medium destroys the imaging resolution, here the speckle pattern the diffuser generates assists in performing super-resolved imaging. Experimental results demonstrate the efficacy of the approach, showing significant improvement in image quality and resolution.

The mechanism and consequently the magnitude of vibrational relaxation of molecules on surfaces differ significantly between insulators and metals, making the vibrational energy transfer at the NO/metal versus the NO/insulator interface a canonical example in the field. We report the influence of the surface temperature, the initial vibrational state, and the incident translational energy on the vibrational relaxation probability of vibrationally excited NO(vI = 3 and vI = 11) undergoing a direct scattering from thin films of vanadium dioxide (VO2) across the Mott transition at 68 °C. At that temperature, thin-film VO2 transforms from the insulating to the metallic phase, exhibiting ∼4 orders of magnitude drop in resistivity. As VO2 undergoes the Mott transition, at T > 68 °C, we observe a surprisingly small, yet measurable enhancement in the relaxation probability of NO(vI = 3 and vI = 11) due to the metallic phase of VO2. The …

Bacteriophages are bacterial viruses that infect and replicate within the bacterial cell using the host cellular machinery. After replication and assembly of multiple viruses, the host cell lyses and releases the newly formed viruses into the environment. There are many telltale signs of infection, one of which is changes in the bacterial membrane potential (MP). Monitoring MP dynamics during the course of a bacteriophage infection event can therefore shed light on the mechanism of phage entry and replication into bacterial cells. In the present work, we study MP dynamics during individual infection events. Our approach combines:(1) a unique VoltageFluor (VF) optical transducer, whose fluorescence lifetime varies as a function of MP via photoinduced electron transfer (PeT) and (2) a quantitative phasor-fluorescence lifetime imaging microscopy (FLIM) analysis for high-throughput readout. This approach enables MP …

Surfactant-stabilized oil-in-water and water-in-oil emulsions, encompassing a wide range of chemical compositions, exhibit remarkable temperature-controlled sphere-to-icosahedron droplet shape transformations. These transformations are controlled by the elasticity and closed-surface topology of a self-assembled interfacial crystalline monolayer. Since many practical emulsions are synergistically costabilized by both surfactants and colloidal particles, we explore the influence of surface-adsorbed hydrophobic and hydrophilic colloidal particles on these shape transformations. We find that these shape transformations persist even at high interfacial colloidal densities, despite the colloids disrupting the molecular interfacial crystal’s topology. We employ computer simulations to elucidate the role of colloidal particles in droplet shape control of these widely employed emulsions. Surprisingly, we observe that the …

Over the past few decades, the prevalence of chronic inflammatory and metabolic diseases has risen sharply, coinciding with significant environmental and lifestyle changes. While genetics play a role, the rapid increase suggests that non-genetic factors are key contributors. Among these, the gut microbiota—a vast community of microorganisms residing in the intestines—has emerged as a central regulator of health. A growing body of evidence links microbial imbalances, or dysbiosis, to various diseases, with reduced microbial richness and diversity observed in industrialised populations compared with those in non-industrialised settings. Many beneficial microbial species, once prevalent in the human gut, are now disappearing, likely due to changes in diet, hygiene and antibiotic use. One of the most influential factors shaping the gut microbiota is diet. The Westernised diet, characterised by high consumption of …

The scattering-type Scanning Near-Field Optical Microscope (s-SNOM) is acknowledged as an excellent tool to investigate the optical properties of different materials and biological samples at the nanoscale. In this study we show that s-SNOM data are susceptible to being affected by specific artefacts related to the light diffraction phenomena and to stray contributions from shallow buried, contrast-active, structures. We focus on discussing the diffraction contributions from sample edges, next to those corresponding to one- or two-dimensional periodic structures, and undesired contributions from shallow buried periodic features. Each scenario was examined individually through both experimental methods and simulations. Our experimental findings reveal that such artefacts affect not only s-SNOM images demodulated at the direct-current (DC) component and the fundamental frequency, but also images demodulated at higher harmonic frequencies. We show that image artefacts caused by diffraction resemble the undesirable effects caused by illumination with a laser beam of unstable intensity, and that buried features can yield s-SNOM signals that cannot be distinguished from those originating from the sample surface, in absence of prior knowledge of the sample structure. Performed simulations confirm these experimental findings. This work enhances the understanding of s-SNOM data and paves the way for new data acquisition and postprocessing methods that can enable next-generation s-SNOM imaging and spectroscopy with significantly enhanced signal-to-noise ratio and resolution.

Sodium-ion batteries (SIBs) are considered as the most promising complementary energy storage system for large-scale application due to the high abundance of sodium. However, the irreversible phase transition and slow diffusion kinetics in O3-type layered transition metals oxides cathodes impede the development of advanced SIBs. Here we address this issue by introducing high-entropy doping regulation strategies, a series of NaNi0.4Mn0.3-xFe0.1Ti0.1SnxLi0.05Sb0.05O2 cathodes exhibit an excellent rate performance (>60 mAh g−1 at 6 A g−1) and prolonged cycle performance (capacity retention >80 % after 300 cycles, at 120 mA g−1). The correlations between the chemical compositions and the electrochemical properties in the designed high-entropy transition metal oxides cathodes were elucidated using a combination of analytical tools including all kinds of electrochemical techniques including …

Researchers have been investigating the physical and morphological properties of biodegradable polymer and copolymer films, blending them with other chemicals to solve challenges in medical, industrial, and eco-environmental fields. The present study introduces a novel, straightforward method for preparing biodegradable hydrogels based on polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) for medical applications. The resulting PVA/PVP-based hydrogel uniquely combines the water absorbency, biocompatibility, and biodegradability of the polymer composite. For hygiene products and medical uses, such as wound healing, hydrogen peroxide (HP) was encapsulated in the PVA/PVP hydrogels for controlled release application. Incorporating PVP into PVA significantly enhances the hydrogel water absorbency and improves the mechanical properties. However, to mitigate the disadvantage of high water absorbency which could result in undesired early dissolution, efforts were made to increase the water resistance and the mechanical characteristics of these hydrogels using freeze–thaw (F/T) cycles and chemical crosslinking PVA chains with trisodium trimetaphosphate (STMP). The resulting hydrogels serve as environmentally friendly bio-based polymer blends, broadening their applications in medical and industrial products. The structural and morphological properties of the hydrogel were characterized using Fourier transform infrared spectroscopy (FTIR), environmental scanning electron microscope analysis (E-SEM), and water-swelling tests. The HP controlled release rate was evaluated through kinetic release experiments using …

Magnetic polymeric conduits are developing as revolutionary materials in regenerative medicine, providing exceptional benefits in directing tissue healing, improving targeted medication administration, and facilitating remote control via external magnetic fields. The present article offers a thorough examination of current progress in the design, construction, and functionalization of these hybrid systems. The integration of magnetic nanoparticles into polymeric matrices confers distinctive features, including regulated alignment, improved cellular motility, and targeted medicinal delivery, while preserving structural integrity. Moreover, the incorporation of multifunctional attributes, such as electrical conductivity for cerebral stimulation and optical characteristics for real-time imaging, expands their range of applications. Essential studies indicate that the dimensions, morphology, surface chemistry, and composition of magnetic nanoparticles significantly affect their biocompatibility, degrading characteristics, and overall efficacy. Notwithstanding considerable advancements, issues concerning long-term biocompatibility, biodegradability, and scalability persist, in addition to the must for uniform regulatory frameworks to facilitate clinical translation. Progress in additive manufacturing and nanotechnology is overcoming these obstacles, facilitating the creation of dynamic and adaptive conduit structures designed for particular biomedical requirements. Magnetic polymeric conduits, by integrating usefulness and safety, are set to transform regenerative therapies, presenting a new avenue for customized medicine and advanced healthcare solutions.

Suspended (“free-standing”) graphene samples were irradiated with noble gas ions at varying energies, while maintaining a constant ion velocity. The resulting defect formation was analyzed using Raman spectroscopy. This process is attributed to the combined effects of nuclear and electronic mechanisms. While the efficiency coefficient (yield) is determined based on calculations for the nuclear mechanism, experimental results reveal that the defect concentration remains consistent for ions of different masses but identical velocities. This observation is interpreted as evidence of the electronic mechanism's contribution to defect formation, where the energy transferred to the graphene lattice primarily depends on the ion's velocity through the lattice rather than its mass.The results of the study show that increasing ion velocity leads to larger defect structures, providing a controllable approach for tuning defect size in …

Amidst the pervasive threat of bacterial afflictions, the imperative for advanced antibiofilm surfaces with robust antimicrobial efficacy looms large. This study unveils a sophisticated ultrasonic synthesis method for cellulose nanocrystals (CNCs, 10–20 nm in diameter and 300–900 nm in length) and their subsequent application as coatings on flexible substrates, namely cotton (CC-1) and membrane (CM-1). The cellulose nanocrystals showed excellent water repellency with a water contact angle as high as 148° on the membrane. Noteworthy attributes of CNC-coated substrates include augmented reactive oxygen species (ROS) generation, heightened surface hydrophobicity, and comprehensive suppression of both drug-sensitive (MDR E. coli and MRSA) and susceptible (E. coli and S. aureus) planktonic and biofilm bacterial proliferation. In contrast, the uncoated substrates display 100% bacterial growth for the above bacteria. Empirical data corroborate the pronounced biofilm mass reduction capabilities of CNC-coated substrates across all tested bacterial strains. Elucidation of underlying mechanisms implicates ROS generation and electrostatic repulsion between CNCs and bacterial membranes in the disruption of mature biofilms. Hydroxyl radicals, superoxide, and hydrogen peroxide possess formidable reactivity, capable of disrupting essential biomolecules such as DNA, proteins, and lipids. The engineered CNC-coated substrates platform evinces considerable promise in the realm of infectious disease management, offering a cogent blueprint for the development of novel antimicrobial matrices adept at combating bacterial infections with …