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Being the first intrinsic antiferromagnetic (AFM) topological insulator (TI), MnBiTe is argued to be a topological axion state in its even-layer form due to the antiparallel magnetization between the top and bottom layers. Here we combine both transport and scanning microwave impedance microscopy (sMIM) to investigate such axion state in atomically thin MnBiTe with even-layer thickness at zero magnetic field. While transport measurements show a zero Hall plateau signaturing the axion state, sMIM uncovers an unexpected edge state raising questions regarding the nature of the "axion state". Based on our model calculation, we propose that the edge state of even-layer MnBiTe at zero field is derived from gapped helical edge states of the quantum spin Hall effect with time-reversal-symmetry breaking, when a crossover from a three-dimensional TI MnBiTe to a two-dimensional TI occurs. Our finding thus signifies the richness of topological phases in MnBTe that has yet to be fully explored.
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http://dx.doi.org/10.1038/s41467-022-35482-0 | DOI Listing |
ACS Chem Neurosci
September 2025
Chemical and Biomolecular Engineering Dept, University of California, Los Angeles, Los Angeles, California 90095, United States.
Simulations in three dimensions and time provide guidance on implantable, electroenzymatic glutamate sensor design; relative placement in planar sensor arrays; feasibility of sensing synaptic release events; and interpretation of sensor data. Electroenzymatic sensors based on the immobilization of oxidases on microelectrodes have proven valuable for the monitoring of neurotransmitter signaling in deep brain structures; however, the complex extracellular milieu featuring slow diffusive mass transport makes rational sensor design and data interpretation challenging. Simulations show that miniaturization of the disk-shaped device size below a radius of ∼25 μm improves sensitivity, spatial resolution, and the accuracy of glutamate concentration measurements based on calibration factors determined .
View Article and Find Full Text PDFInorg Chem
September 2025
College of Chemistry and Materials Science, The key Laboratory of Functional Molecular Solids, Ministry of Education, The Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education Institutes, Anhui Provincial Engineering Laboratory for New-Energy Vehicle Battery Energy-Storage Materia
Conventional acid-catalyzed acetalization faces significant challenges in catalyst recovery and poses environmental concerns. Herein, we develop a CeO-supported Pd single-atom catalyst (Pd/CeO) that eliminates the reliance on liquid acids by creating a localized H-rich microenvironment through heterolytic H activation. X-ray absorption near-edge structure and extended X-ray absorption fine structure analyses confirm the atomic dispersion of Pd via Pd-O-Ce coordination, while density functional theory (DFT) calculations reveal strong metal-support interactions (SMSI) that facilitate electron transfer from CeO oxygen to Pd, downshifting the Pd d-band center and optimizing H activation.
View Article and Find Full Text PDFFront Plant Sci
August 2025
College of Engineering, Qinghai Institute of Technology, Xining, China.
The plateau pika () is a keystone species on the Qinghai-Tibet Plateau, and its population density-typically inferred from burrow counts-requires rapid, low-cost monitoring. We propose YOLO-Pika, a lightweight detector built on YOLOv8n that integrates (1) a Fusion_Block into the backbone, leveraging high-dimensional mapping and fine-grained gating to enhance feature representation with negligible computational overhead, and (2) an MS_Fusion_FPN composed of multiple MSEI modules for multi-scale frequency-domain fusion and edge enhancement. On a plateau pika burrow dataset, YOLO-Pika increases mAP50 by 3.
View Article and Find Full Text PDFStruct Heart
September 2025
The Carl and Edyth Lindner Research Center at the Christ Hospital, Cincinnati, Ohio, USA.
Severe, untreated tricuspid regurgitation is associated with worse clinical outcomes. While isolated tricuspid valve (TV) surgery has been linked to poor long-term outcomes, transcatheter TV therapies, including edge-to-edge repair and transcatheter tricuspid valve replacement (TTVR), have emerged as effective alternatives and have been shown to improve outcomes, leading to their regulatory approval in the United States. Conduction system abnormalities are commonly seen among patients undergoing TTVR due to the close proximity of the atrioventricular node and the His bundle to the TV annulus.
View Article and Find Full Text PDFChem Sci
September 2025
State Key Laboratory of Crystal Materials, Tianjin Key Laboratory of Functional Crystal Materials, Institute of Functional Crystals, Tianjin University of Technology Tianjin 300384 China
Nonlinear optical (NLO) crystals capable of expanding the spectral region of solid-state are of great importance for many high-tech applications, yet their rational structure design remains a great challenge because of the conflicting property requirements among second harmonic generation (SHG) response, ultraviolet (UV) cut-off edge, and birefringence. Herein, based on the chemical disubstitution of the classic NLO crystal SrBeBO (SBBO), , substituting [BO] triangles with larger π-conjugated [BO] groups and substituting high-toxic [BeO] tetrahedra with environment-friendly [AlO] tetrahedra, a new high-performance aluminoborate NLO crystal, BaAlBO, has been successfully designed and synthesized. The theoretical calculations and optical property measurements indicate that BaAlBO exhibits not only the largest SHG response among the reported aluminoborates (2.
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