Browse Articles

Synergistic Modulation of Intermediate Adsorption and Active Hydrogen Supply Enable Pulsed Nitrate‐to‐Hydroxylamine Electroreduction with Nearly 100% Faradaic Efficiency

Abstract Electrochemical hydroxylamine (NH 2 OH) synthesis from NO x under ambient conditions presents a sustainable alternative to energy‐intensive industrial methods, but its selectivity remains limited by unbalanced active hydrogen (H*) supply and intermediate adsorption. Herein, we develop boron‐doped amorphous Bi metallene arrays for efficient nitrate‐to‐NH 2 OH electroreduction. In situ spectroscopy and theoretical calculations reveal that the amorphous structure and B‐induced p‐sp orbital hybridization modulate the electronic structure, optimizing intermediate adsorption while enhancing H* generation. These synergistic effects collectively reduce the energy barrier of the potential‐determining step, significantly improving catalytic activity and selectivity. The catalyst achieves an NH₂OH Faradaic efficiency (FE) of 85.3% at −0.4 V versus reversible hydrogen electrode (RHE). By employing a pulsed potential strategy, the FE further increases to nearly 100%, surpassing most reported counterparts. This work not only proposes a novel catalyst design leveraging amorphous engineering and orbital hybridization but also demonstrates the efficacy of pulsed electrolysis in steering reaction pathways for electrosynthesis.

Gastrointestinal tract disease classification from wireless capsule endoscopy images based on deep learning information fusion and Newton Raphson controlled marine predator algorithm

Impact of oxygen plasma pulse time on atomic-layer-deposited ZrO2 antiferroelectric energy storage capacitors

Fluorite-structured antiferroelectric (AFE) dielectric capacitors have emerged as promising candidates in energy storage applications. The AFE behaviors of dielectrics generally stem from an electric field-induced phase transition. Thus, the initial phase composition in the AFE film plays an important role in determining the performance of energy storage. This work systematically investigates the impact of oxygen plasma pulse time (OPPT) on the AFE properties of atomic-layer-deposited ZrO2 films. As the OPPT increases from 3 to 5 s, the as-deposited ZrO2 film changes from an amorphous to polycrystalline state. The ratio of cubic/tetragonal phase (C/T) in the polycrystalline ZrO2 film gradually rises with increasing the OPPT from 5 to 15 s, accompanied by a gradual decrease in defect oxygen. To improve the performance of the as-deposited ZrO2 capacitors, post-annealing is performed at 450 °C for 30 min in the forming gas. It is found that the post-annealing increases the concentration of the T phase in the ZrO2 films, which reduces gradually with prolonging the OPPT. For the amorphous as-deposited ZrO2 film under an OPPT of 3 s, the post-annealing generates the largest maximum polarization (Pmax) and energy storage density, corresponding to 19.7 μC/cm2 and 34.7 J/cm3, respectively. The results indicate that the AFE properties of the ZrO2 film are determined by the T phase content, which can be modulated by the oxygen plasma dosing duration and post-annealing. Our findings provide a different perspective for improving the energy storage performance of AFE capacitors.

Probing stress and magnetism at high pressures with two-dimensional quantum sensors

Thrombus enhancement as a predictor of embolic in acute basilar artery occlusion

Suppressing endurance degradation in lead-free perovskite Cs3Bi2Br9 memristors: Grain engineering via annealing temperature and grain boundary passivation with PEG additive

Lead-free Cs3Bi2Br9 perovskite memristors have emerged as promising candidates for nonvolatile memory and neuromorphic computing due to their environmental friendliness and stability. However, their practical applications are hindered by severe endurance degradation during repetitive resistive switching (RS) cycles, attributed to incomplete RESET of conductive filaments (CFs) at grain boundaries (GBs). Herein, we systematically investigate this degradation mechanism and propose two innovative strategies to enhance device endurance: (1) grain engineering via thermal annealing to reduce GB density and (2) GB passivation using polyethylene glycol (PEG) additives. By optimizing annealing temperatures (100–250 °C), Cs3Bi2Br9 films exhibit progressively larger grain sizes (158.6–295.2 nm), which delays high resistance state degradation by minimizing CF nucleation sites. However, residual GBs still permit partial Ag accumulation. To address this, PEG incorporation chemically passivates GBs, effectively blocking ion migration and trapping. The optimized PEG-passivated Ag/Cs3Bi2Br9:PEG/ITO memristor achieves remarkable improvements: endurance is extended from 100 to 1000 cycles, and the switching window expands from 6 to 176 times. Furthermore, the optimized device demonstrates continuous conductance modulation for multilevel storage and synaptic function emulation, enabling a 784–100–10 fully connected neural network to achieve 92.2% recognition accuracy on the MNIST dataset after 100 training epochs. This study elucidates the GB-mediated degradation mechanism and demonstrates that combining grain size optimization with GB passivation provides a universal framework for high-performance RS devices in neuromorphic computing and nonvolatile memory.

Longitudinal liquid biopsy identifies an early predictive biomarker of immune checkpoint blockade response in head and neck squamous cell carcinoma

Abstract Immune checkpoint blockade (ICB) has improved outcomes for patients with head and neck squamous cell carcinoma (HNSCC), but predictive biomarkers remain limited. Here, we use a time-resolved, multi-omic approach in a murine HNSCC model to characterize peripheral immune responses to ICB. Single-cell transcriptomics and T/B cell receptor analyses  reveal early on-treatment expansion of effector memory T and B cell repertoires in responders, preceding tumor regression. These dynamic immune features inform a composite transcriptional signature that accurately predicts ICB response in independent human HNSCC cohorts. LiBIO outperforms existing biomarkers and generalizes to melanoma, non-small cell lung cancer, and breast cancer without retraining. These findings suggest that early treatment-induced changes in circulating immune repertoires reflect the host’s capacity to mount an effective antitumor response. This work provides a framework for leveraging transient peripheral immune dynamics to develop non-invasive, high-fidelity biomarkers for response to immunotherapy across cancer types.

Bioinformatic analyses and validated experiments reveal an aging hallmark gene set and protective miR of coronary artery disease

Two-terminal Li+-based memristors with synchronous conductance modulation of Li-source/Li-reservoir layer for high-accurate image recognition

Memristors, characterized by in-memory computing and low-power consumption, are considered an ideal paradigm for building artificial neural networks and overcoming the von Neumann bottleneck. The two-terminal Li+-based memristor features simple structure and controllable weight update. However, existing works normally focus on the exclusive resistive switching layer, which is commonly the Li-source layer, and ignore the effect of another variable layer. In this study, a synchronous conductance modulation approach is developed by coupling the synchronously modulated layers of TT-Nb2O5 and LiCoO2 in the device. The linearity of the device was measured at 0.29, leading to a high recognition accuracy, with an average image recognition rate of 95.8% and a low standard deviation of 1.7%. This work offers an alternative option for developing two-terminal memristors.

Hydrocarbothermal flow synthesis of carbon-supported small and dense high-entropy alloy nanoparticles as electrocatalysts

An efficient voltammetric platform integrating ZnS nanowires, reduced graphene oxide sheets, and ferrocene monocarboxylic acid for the sensitive detection of homocysteine

Dipole engineering in self-assembled monolayers for efficient organic–silicon hybrid solar cells

Organic–silicon hybrid solar cells, as dopant-free heterojunction devices, hold significant potential for achieving high performance-to-cost ratios in photovoltaics. Critical to their advancement is the engineering of carrier-selective contacts that minimize interfacial losses. Here, we demonstrate a carbazole-based self-assembled monolayer (SAM), [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz), as an efficient electron-selective layer in [poly(3,4 ethylenedi oxythiophene):polystyrene sulfonate (PEDOT:PSS)]/Si solar cells. The Me-4PACz SAM introduces a directional dipole moment at the c-Si/Al interface, generating a built-in electric field that enhances electron extraction. This interface modification leads to a linear Ohmic contact, reducing the contact resistivity between n-Si and the metal electrode interface to 4.12 mΩ cm2. Consequently, the optimized device achieves a power conversion efficiency (PCE) of 16.75% with a high open-circuit voltage (VOC) of 651 mV and fill factor of 78.03%, representing a ∼14% relative PCE improvement over the control device (PCE = 14.75%). Our work provides a molecular-scale strategy for tailoring carrier dynamics in silicon-based heterojunctions, offering a pathway toward low-cost, high-efficiency photovoltaic technologies.

Capillary constrictions prime cancer cell tumorigenicity through PIEZO1

Abstract Metastasis is responsible for most cancer-related deaths. However, only a fraction of circulating cancer cells succeed in forming secondary tumours, indicating that adaptive mechanisms during circulation play a part in dissemination. Here, we report that constriction during microcapillary transit triggers reprogramming of melanoma cells to a tumorigenic cancer stem cell-like state. Using a microfluidic device mimicking physiological flow rates and gradual capillary narrowing, we show that compression through narrow channels causes cell and nuclear deformation, rapid chromatin remodelling and increased calcium signalling via mechanosensor PIEZO1. Within minutes, cells upregulate transcripts associated with metabolic reprogramming and metastatic processes. Over time, this results in the stable adoption of a cancer stem cell-like state. Squeezed cells express elevated melanoma stem cell markers, exhibit increased trans-endothelium invasion and display enhanced tumorigenicity in vitro and in vivo. Pharmacological inhibition of PIEZO1 blocks this transition, while activation with Yoda1 induces the stem cell-like state irrespective of constriction. Deletion of PIEZO1 completely abolishes the constriction-induced phenotype. Together, these findings demonstrate that compressive forces during circulation reprogram circulating cancer cells into tumorigenic, stem cell-like states, primed for extravasation and metastatic colonization.

Emission characteristics of Eu$$^{2+}$$ and Eu$$^{3+}$$ under x-ray and alpha irradiation in Eu-doped CaF$$_2$$ crystals

Reference black-body radiation source for emissivity measurements on the frequency range 3–30 THz

The emergence of radiation sources in different frequency ranges fuels the demand for techniques for spectrally resolved calibrations of their intensity. Thermal radiation of a perfectly absorbing object (black-body radiation) is used as an etalon in the near-infrared–visible ranges. However, to date, no suitable material exists as a reference for thermal radiation in the frequency range 3–30 THz. In this work, we demonstrate a thermal source that can serve a broad THz frequency range. We employ a moth-eye-structured silicon coated with conductive graphitic film exhibiting absorbance above 99.5%. By using the thermal emission of a silicon-based Salisbury screen heated at a temperature of 60 °C we demonstrate that the moth-eye structure can be used for calibrating THz devices. We also show that the developed approach may allow one to engineer the spectrum of the frequency comb source using a two-layer heterostructure.

In situ and remote observations of the ultraviolet footprint of the moon Callisto by the Juno spacecraft

Abstract Jupiter exhibits peculiar multiwavelength auroral emissions resulting from the electromagnetic interactions of Io, Europa, and Ganymede with the magnetospheric plasma flow. Characterizing the faint auroral footprint of the fourth Galilean moon, Callisto, has always been challenging because of its expected weakness and its proximity to Jupiter’s bright main aurora. Here, we report on unusual magnetospheric conditions that led to an equatorward shift of Jupiter’s main auroral oval unveiling the auroral footprints of the four Galilean moons in a single observation. Remote observations by the Juno spacecraft reveal a double-spot structure, characteristic of the footprints of the other three moons, with a maximum ultraviolet brightness of 137 $$\pm$$ ± 15 kR. Concurrent observations within Callisto’s flux tube reveal field-aligned electrons with a characteristic energy of 10 keV, depositing an energy flux of 55 mW.m-2 in Jupiter’s atmosphere. The electron properties are consistent with the triggering of radio emissions with intensities lower than 5 × 10-18 W.m-2.Hz-1.

Enhanced composed fashion image retrieval with a multi-hop reasoning framework

Synergistically stabilized O3-type layered oxide cathodes via phase regulation of multi-cation doping enable high-performance sodium-ion batteries

O3-type layered oxides, as high-capacity cathode materials for sodium-ion batteries (SIBs), face practical limitations due to poor structural stability, high Na+ diffusion barriers, and inadequate rate performance. This work proposes a Ca/Cu/Ti co-doping strategy and systematically regulates the crystal phase among 24 types of layered oxides, from P2-, mixed P2/O3- to O3-type phase, by precisely controlling the Na content and adjusting the transition metal layer microenvironment. The optimum O3-type Na0.80Ca0.06Ni0.48Mn0.40Cu0.06Ti0.06O2 delivers a high initial capacity of 151.37 mAh g−1 at 1 C (120 mA g−1) with 102.56 mAh g−1 retained after 200 cycles, while maintaining 80.67% capacity retention after 100 cycles at 0.1 C. Mechanistic studies and theoretical calculations demonstrate that an optimal Ca/Cu/Ti doping improves the Na+ diffusion kinetics, where Na vacancies activate Cu/Ni redox activity to sustain capacity under Na+-deficient conditions, and effectively suppresses Mn activity, thereby simultaneously enhancing the cycling stability of cathodes. This work provides a wide range of component-phase regulation, achieving highly stable Na-deficient O3-type layered oxides through a multi-cation trace doping strategy for SIBs.

AEBP1 drives fibroblast-mediated T cell dysfunction in tumors

Enhancing direct torque control of doubly fed induction motor in electric vehicle using artificial neural networks