Browse Articles

Design and Development of DNA Damage Chemical Inducers of Proximity for Targeted Cancer Therapy

Nickel-Induced Lattice Defects Limit Proton Uptake in Barium Zirconate Electrolytes

Accessing terapascal pressures on two-stage light-gas guns for high-energy-density research

We present pressure amplifiers that have been developed to enable the study of material behavior at terapascal (TPa) pressures using two-stage light-gas gun (2SLGG) facilities. When impacted by a hyper-velocity projectile, Mach reflections within the pressure amplifier eventually merge to form a Mach stem, generating a planar output shock that greatly exceeds the initial drive. Validation experiments demonstrated that peak pressures of 0.6 and 1.073 TPa were achieved in quartz samples for two different amplifier designs. These pressures represent an approximately fivefold increase over the sample pressures typically attainable at 2SLGG facilities. The temporal and spatial uniformity of the pressure drive is suitable for high-precision equation-of-state measurements of materials relative to a shock standard. This work greatly extends the capabilities of 2SLGG facilities and opens new avenues of study in high-energy-density physics using these drivers.

Transient Imaging of the Oxygen Reduction Reaction at Single Nanocatalysts

Predicting vacancy formation energies in refractory non-dilute random alloys using improved graph-based machine learning models trained on density functional theory data

This study employs four machine learning (ML) models—random forest (RF), XGBoost, graph convolutional networks (GCN), and graph attention networks (GAT)—to predict vacancy formation energies (VFEs) in refractory non-dilute random alloys including pure metals, binary, ternary, quaternary, and quinary systems based on Mo, Nb, Ta, V, and W. Training data are generated from density functional theory calculations. Among all elements, W has the highest VFE on average (2.866 → 3.517 eV from pure metal to ternary), while Ta is the only element whose VFE rises monotonically (2.841 → 3.262 eV from pure metal to quinary). In tree-based tabular models (RF, XGBoost), each chemical composition is encoded as a five-dimensional vector of elemental fractions on the Mo–Nb–Ta–V–W basis, augmented with a categorical indicator of the specific element in a certain alloy for which the vacancy is created, and features are standardized to balance input scales during training. In graph models (GCN, GAT), each composition is represented as a small graph whose nodes carry per-element descriptors (fraction, atomic number, and Magpie features), while edges summarize simple pairwise chemistry (such as fraction interactions and differences in atomic number, electronegativity, covalent radius, and Mendeleev number). All four models achieve high accuracy in predicting VFEs across alloy orders, with graph-based approaches capturing chemistry-aware trends beyond fixed tabular descriptors. Among the four, GCN attains the highest accuracy with R2=0.972, root mean squared error =0.051 eV, and mean absolute error =0.042 eV, outperforming GAT and the tabular baselines. These results underscore the promise of graph-based ML for rapid, reliable prediction of VFEs in the refractory alloy design.

Exciton-mediated optical transitions in PVA composites containing xerogel, amorphous, and crystalline silica from rice husks

Polyvinyl alcohol (PVA) is a polymer known for its fluorescence; however, its relatively low exciton formation restricts its potential in optoelectronic devices. This study aims to enhance the optical properties of PVA by incorporating silica fillers (xerogel, amorphous, or crystalline) derived from rice husks, thereby creating silica-dispersed PVA composites. The composites were fabricated by solution casting at a PVA-to-filler mass ratio of 9:1. Structural, absorbance, and fluorescence analyses were performed on the samples. Embedding the different silica polymorphs enhanced photon absorption; moreover, it also improved excitation for the π–π* transitions by approximately 7.86, 1.72, and 1.01 times for PVA filled by xerogel, amorphous, and crystalline silica, respectively, compared to unfilled PVA. The composites also displayed a broadened excitation shoulder, enabling a broader excitation wavelength range. This enhancement is caused by the increase in the stiffness and bond strength of the PVA molecules induced by compressive stress resulting from its physical interactions with the filler, as well as B2 defect and hydroxyl dioxasilyrane clusters, which participate in promoting exciton formation. As a result, π–π* excitation is boosted, especially in the ultraviolet region, and an increased excitation shoulder intensity is observed between 360 and 425 nm. This higher excitation correlates with a greater emission intensity in the same hierarchical order as the excitation trend. The emission peak position remains relatively constant, with a slight Stokes shift toward the violet region owing to exciton internal conversion. PVA/silica composites also exhibited more complex emission patterns and a lower average lifetime than unfilled PVA.

Disulfide-Directed Multicyclic Peptides for Chimeric Antigen Receptors Targeting Solid Tumors

Epitaxial configuration of unidirectionally aligned MoS2 monolayer on sapphire

Highly oriented MoS2 monolayer (ML) on the sapphire(0001) substrate was grown by metal-organic chemical vapor deposition. The epitaxial configuration of ML-MoS2/sapphire has been studied using low-energy electron diffraction (LEED) combined with first-principles calculations. LEED analysis based on the dynamical diffraction theory revealed that the MoS2 ML is grown with the epitaxial relationship of MoS2 [112¯0] // Al2O3 [112¯0] and MoS2 [11¯00] // Al2O3 [11¯00] and that the formation of antiparallel (inversion) domains is effectively suppressed. The observed epitaxial relationship is insensitive to the direction of surface steps on the sapphire substrate.

Fused-Ring Electron Acceptors as a Versatile Additive Platform for Efficient Perovskite Photovoltaics

Enhancing conductivity and near-infrared optical transparency of transparent conductive electrodes through Ag nanowire incorporation and DMSO post-treatment

Exploring the enhancement of PEDOT:PSS transparent conductive films through the incorporation of silver nanowires (AgNWs) and a highly effective yet simplified post-treatment strategy using a single-step dimethyl sulfoxide (DMSO) spin-coating process. The improvement in conductivity was attributed to the optimal AgNW blending ratio and the beneficial effects of post-treatment on film composition, as revealed by x-ray photoelectron spectroscopy (XPS). UV–Vis transmittance measurements demonstrated improved optical transparency in the near-infrared (NIR) range, attributed to the enhanced film morphology achieved through DMSO treatment. We conducted a thorough investigation across a wide composition range (0%–80% AgNWs). The optimal configuration, comprising 50% AgNWs with DMSO post-treatment, achieved the highest conductivity of 3227 S cm−1. The transmittance uniformity is defined as the flatness of the transmittance spectrum across the NIR band. A film with superior uniformity exhibits a smaller decrease in transmittance over the wavelength range of interest. We are the first to systematically optimize for and achieve exceptional NIR transmittance uniformity, with a minimal decrease of only 8.9% across this broad band, remaining above 83% at 1800 nm. These findings demonstrate a viable approach for developing high-performance transparent conductive electrodes with enhanced electrical and optical properties, suitable for NIR-based optoelectronic devices.

Reductive Arylation of PVC by Dual-Metal Catalyzed Cross-Electrophile Coupling

Time-resolved study of thermal effects in p-InAsSb/n-InAs0.78Sb0.22 negative luminescence devices

Analysis of optical signal variation during and after a single 500 μs pumping pulse in p-InAsSb/n-InAs0.78Sb0.22 diodes at forward and reverse biases measured in a broad band (2–14 μm), a long wave (8–14 μm), and a mid-wave (2–8 μm) infrared regions revealed a dominant role of the metal/p-InAsSb junction in the diode temperature change. Heat pumping ability vs current and vs temperature in p-InAsSb/n-InAs0.78Sb0.22 samples at a reverse bias have been qualitatively explained within the ranks of existing ideas on thermoelectric effects in diodes with a thin base and metal contacts.

Geminal Cl-Bridged Dual-Fe-Atom Catalyst for Efficient and Stable Oxygen Reduction Reaction

Analytical model for balling defects in laser melting using rivulet theory and solidification

In laser welding and additive manufacturing communities, the balling (humping) defect is primarily attributed to the Plateau–Rayleigh fluid instability (PRI) with a few authors suggesting fluid jetting and volume conservation as alternative mechanisms. As analytical descriptions of these mechanisms are unavailable, combining them into a single formalism is unfeasible. We present a new model of PRI with higher accuracy, accounting for competition with solidification, to compare the expected behavior with known experimental trends when fluid jetting is neglected. We adapt a rivulet instability model from fluid physics to account for the stabilizing effects of the substrate, which the traditional cylindrical-jet geometry does not account for and estimate the instability growth rate. Our model yields a continuous transition from non-balling to balling hitherto lacking in current literature and predicts instability growth at higher wavelengths with strong sensitivity to the solidification front curvature. While the fluid surface is most unstable for shallow melt pools, the absolute magnitude of balling relevant to printing defects scales with melt pool depth and has a maximum for a given melt pool geometry. Synchrotron-based x-ray radiography of thin samples indicates that PRI growth rates and solidification can be comparable in magnitude and thus compete, as we find in this work. We predict that deviations between model predictions and our experimental results demonstrate the importance of fluid flows and heat transport in the balling process. Our experiments further demonstrate at least one mechanism by which the melt pool length and the balling wavelength are not equivalent, as commonly claimed.

Quantitative Membrane Paramagnetic Relaxation Enhancement (mPRE) Measurements on Lipid-Anchored Proteins: Insight into Orientational Dynamics

Variational quantum eigensolver models of molecular quantum dot cellular automata

Molecular quantum-dot cellular automata (QCA) may provide low-power, high-speed computational hardware for processing classical information. Simulation and modeling play an important role in the design of QCA circuits because fully coherent models of QCA scale exponentially with the number of devices, and such models are severely limited in size. For larger circuits, approximations become necessary. In the era of fault-tolerant quantum computation, however, it may become possible to model large QCA circuits without such limitations. This work explores the use of the noisy-intermediate scale quantum (NISQ) variational quantum eigensolver (VQE) method for estimating the ground state of QCA circuits. This is relevant because the computational result of a QCA calculation is encoded in the circuit’s ground state. In this study, VQE is used to model logic circuits, including binary wires, inverters, and majority gates. VQE models are performed by ideal simulators, noisy simulators, and actual quantum hardware. This study demonstrates that VQE may indeed be used to model molecular QCA circuits. It is observed that using modern NISQ hardware, results are still quite sensitive to noise, so measures should be taken to minimize noise. These include simplifying the ansatz circuit whenever possible and using low-noise hardware.

Discovery of Supra-Bivalent GSK3β Inhibitory Peptides Containing an ATP-Mimetic Amino Acid

Pressure-induced anomalous suppressed thermal conductivity in MgX (X = Se, Te): Soft phonon modes and enhanced four-phonon scattering

Understanding the mechanism by which pressure modulates lattice thermal conductivity has been a focus in the study of thermal transport. In this work, based on the first-principles calculations combined with the phonon Boltzmann transport equation, this study reveals an anomalous pressure dependence of the thermal conductivity in MgX (X = Se, Te) with the F-43m phase. After applying pressure, the thermal conductivity of MgSe and MgTe decreases by 63% and 74%, respectively, at room temperature. This anomalous relationship is mainly due to the softening of the transverse acoustic (TA) mode. The softening of the TA mode leads to an increase in the Grüneisen parameter, resulting in larger anharmonicity, which in combination with the enlarged scattering channels leads to an increase in the scattering rate, thus suppressing the thermal transport efficiency. The calculations show that the elastic property analysis is applicable to measure the magnitude of anharmonicity in both materials. In addition, it is found that higher-order phonon scattering is a non-negligible factor in studying the effect of pressure on thermal transport properties. After considering the four-phonon scattering process, the thermal conductivity of MgSe and MgTe decreases by more than 25% under pressure compared to values calculated when only the three-phonon scattering process is considered. These findings reveal the mechanisms behind the anomalous pressure dependence of thermal conductivity and highlight the importance of high-order phonon scattering in the context of pressure-modulated thermal transport.

Mapping the Undirected Borylation of C(sp ³ )–H Bonds in Strained Rings

Solid–liquid phase transitions of deuterium under microspherical confinement

We investigated the solid–liquid phase transition of deuterium (D2) in microspheres using relaxation calorimetry. By developing a point-by-point analysis method for the temperature–time curves, we identified a sudden change in heat during the solid–liquid phase transition and determined the phase-transition temperature with the help of the heat-transfer equations. The heating power and cooling rate were found to affect the solid–liquid phase-transition temperature, while the spatially nonuniform distribution of D2 within microspheres is deduced to result in multiple liquid–solid transition processes, causing an obvious temperature fluctuation with time. Our work presents a physical foundation for understanding the phase-transition characteristics of molecular solids at the micrometer scale and introduces novel strategies for in situ measurement of the phase-transition temperature of fusion fuels at low temperatures.