Browse Articles

High‐Performance Artificial Lithium Channel Enabled by a Brominated Organic Imine Cage

ABSTRACT Despite extensive advancements in the design of artificial transporters for K + , Cl − and water, the development of Li + ‐selective systems has remained comparatively neglected, largely due to its smaller ionic radius and higher hydration energy that pose significant design challenges. To date, only three classes of artificial Li + transporters have been reported. In this work, we introduce a novel fourth class of artificial Li + channels, constructed from unique self‐assembling organic imine cages that form membrane‐spanning porous architectures. By incorporating bromine substituents, the resulting channel exhibits not only the highest Li + transport activity (EC 50 of 0.017 mol‰, relative to lipids) but also unprecedented selectivity, with Li + /Na + and Li + /K + selectivity factors of 44 and 52 respectively, marking a new benchmark in transmembrane Li + transport performance.

Dynamic teaching path generation for quadruped robot programming by integrating R-GCN and SBERT

Mechanism Reevaluation and Reaction Development in Rhodium‐Catalyzed Cycloaddition of <i>gem</i> ‐Difluorinated Cyclopropanes

ABSTRACT Transition‐metal‐catalyzed cycloadditions of strained carbocycles have emerged as a powerful strategy for constructing complex molecular architectures through C–C bond reorganization. We previously reported a Rh‐catalyzed (3 + 2) cycloaddition of gem ‐difluorinated cyclopropanes ( gem ‐DFCPs) with internal olefins, which was initially interpreted to proceed via a conventional cycloaddition mechanism. Mechanistic interrogation, through control experiments and DFT calculations, now reveals that this transformation proceeds through a previously unrecognized pathway involving dual C–C/C–F bond activation. The unusual cyclization mechanism involves fluoroallylic substitution, carbocation‐mediated intramolecular cyclization, and fluoride transfer. This revised mechanistic framework not only redefines the understanding of such cycloadditions but also directly inspires the development of new reactions.

Simultaneous removal of fluoride and arsenic from water in a fixed-bed column using Fe-Al-MOF/CF composite: optimization by response surface methodology

Control of Conformation and Spin for Programmable Singlet‐Triplet Exciton Balance in Through‐Space Charge‐Transfer Emitters

ABSTRACT Achieving continuous and predictable control over singlet‐triplet exciton partitioning in solution remains challenging for organic molecules, partly because electronic structure, conformational dynamics, and nonradiative decay are intertwined. Here we introduce a dual‐key, coordination‐activated through‐space charge‐transfer (TSCT) platform that enables programmable modulation of spin‐dependent excited‐state pathways in solution. Flexible donor‐σ‐acceptor ligands Cz‐nC‐TPP comprising a carbazole donor (Cz) and a terpyridine acceptor (TPP) linked by alkyl spacers ( n = 2, 4, 6, 8) predominantly emit from local excited states and show negligible oxygen sensitivity before metal binding. Upon coordination with ZnX 2 (X = Cl, Br, I), a TSCT channel is activated without covalent re‐engineering, producing microsecond delayed fluorescence consistent with TSCT‐based thermally activated delayed fluorescence. Spacer length acts as a geometric key that regulates access to folded TSCT geometries and Δ E ST , whereas halide identity serves as a spin key that tunes spin‐orbit coupling and triplet involvement. Together, these inputs enable predictable modulation of delayed, triplet‐associated emission across the series. Notably, the Cz‐6C‐TPP‐ZnBr 2 complex shows the best balance between delayed‐emission prominence and overall brightness. This programmability enables a modular library of dissolved‐oxygen probes with turn‐off and ratiometric responses, visible color evolution, low detection limits, and rapid, reversible responses.

Development and validation of the student readiness and anxiety scale for AI-assisted biology teaching (SRAS-AIBT)

Room‐Temperature Gas‐Phase CO ₂ ‐to‐C ₃ Coupling by a 4 <i>f</i> ‐Aromatic Cluster

ABSTRACT Room‐temperature conversion of CO 2 into value‐added multi‐carbon products (C 3 or C 3+ species) remains a major challenge due to poor selectivity and limited C−C coupling pathways. Using mass spectrometry, photoelectron imaging spectroscopy, and density functional calculations, we identify the 4 f ‐metalla‐aromatic anion PrB 2 C 2 − , which—despite lacking a C─C bond—exhibits σ and π double aromaticity involving a 4 f atom. We show that PrB 2 C 2 − reacts with CO 2 at room temperature to generate C 3 B 2 O 2 − with a C─C─C backbone. The C 3 ‐chain formation occurs in three stages involving two distinct C−C coupling steps enabled by flexible Pr− X bonding ( X = B, C, O) and Pr‐centered electron shuttling. The unique structure of PrB 2 C 2 − directs CO 2 activation toward C─C─C coupling rather than CO release. These findings deepen the understanding of f ‐block‐mediated small‐molecule activation and provide a new and tailored route for producing products with C─C bonds via CO 2 conversion.

Outdoor high-precision 3D dense mapping system based on stereo visual SLAM

Electrochemical Biomimetic Iron‐Catalyzed Benzylic C─H Bonds Hydroxylation

ABSTRACT Electrochemical synthesis has attracted considerable attention as a green synthetic technology in recent years, particularly in the domain of selective oxidation and reduction, which represents a significant yet ongoing challenge in the field. This protocol presents a biomimetic iron‐catalyzed electrochemical benzylic C─H bond hydroxylation through a water activation strategy, where in situ‐generated high‐valent iron‐oxo species mediate, enabling efficient and highly selective benzylic hydroxylation. The method exhibits excellent selectivity and broad functional group compatibility, applicable to primary, secondary, and tertiary benzylic C─H bonds, and suitable for late‐stage modification of bioactive molecules. Mechanistic studies highlight the efficacy of a dual‐control approach combining indirect electrolysis with a detached reaction layer to prevent direct substrate oxidation. This method offers a practical and green route to the synthesis of diverse benzyl alcohols.

Cervical microbial dysbiosis in single HPV16-positive HSIL

Robust Linkage‐Encoded Covalent Organic Framework Membranes Sustain Selective Ion Transport for Energy Harvesting From Concentrated Acids

ABSTRACT Achieving simultaneously high ion permselectivity and chemical robustness in concentrated electrolytes remains a central challenge for membrane‐based technologies, because strong electrostatic screening suppresses charge‐based exclusion while corrosive acids and bases accelerate material degradation. Here we report a molecular strategy to construct robust linkage‐encoded covalent organic framework (COF) membranes in which short‐range ion‐framework interactions are embedded directly within fully conjugated enaminone linkages lining vertically aligned nanochannels. By holding framework topology and pore architecture constant while varying only the linkage chemistry, we show that the linkage microenvironment governs ion selectivity, transport efficiency, and chemical stability. Periodic enaminone motifs create persistent coordination environments and hydrogen‐bond networks that remain effective at high ionic strength, enabling ultrafast proton transport exceeding Nafion 212 by more than fivefold. The membrane preserves crystallinity and pore alignment and maintains performance after exposure to 12 M H 2 SO 4 at 110°C and under concentrated alkaline conditions. To demonstrate performance under extreme conditions, it delivers a peak osmotic power density of 2422.9 W m −2 under a 12 M || 0.01 M H 2 SO 4 gradient while maintaining stable continuous operation. This linkage‐encoding paradigm provides a general route to ion‐selective, chemically resilient membranes for reliable ion transport and electrochemical technologies operating in chemically extreme electrolytes.

Development of a model for design radiation shielding composite aprons using machine learning

Multi‐Color Flexible Electrochromic Device for Smart Anti‐Counterfeiting

ABSTRACT Information security is critically important. We propose a multilevel electrochromic display design for dynamic information encryption, enabled by Prussian blue, zinc, and potassium nickel hexacyanoferrate. The as‐fabricated electrochromic devices offer a two‐dimensional CIE color space modulation with four distinct states from transparent to blue, green, and yellow. The devices facilitate precise, localized, and dynamic modulation of electrochromism via an elaborately designed and independently addressable pattern configuration, enabling advanced encryption and identity authentication with enhanced adaptability. This approach achieves superior security through multi‐stage authentication, real‐time color modulation, and adjustable smart encryption levels tailored to different specific requirements. Our work envisions a new generation of flexible electrochromic devices that elevate both display performance and information security.

A multi-domain graph-integrated neural framework for robust acoustic anomaly detection under adverse environmental conditions

Abstract Acoustic event understanding and anomaly detection play a critical role in security monitoring, defence applications, and urban safety, yet current approaches struggle to generalise across noisy environments, rare event categories, and varying distances. To address these limitations, we propose a multi-domain, graph-integrated neural framework that unifies spectral, temporal, and phase representations for robust acoustic modeling. Our architecture combines a triple-stream decomposition - wavelet, gammatone, and complex spectrogram encoders - with a hierarchical cross-modal transformer for multi-scale fusion. Graph-theoretic feature integration, informed by physical propagation constraints, enables robust representation learning, while a memory-augmented contrastive module enhances recognition of rare events. The framework is trained with multi-task objectives encompassing classification, uncertainty-aware distance estimation, and environment-conditioned adaptation. Evaluations across seven benchmark datasets, including UrbanSound8K, ESC-50, FSD50K, DCASE, and MAD, demonstrate strong multi-task performance across classification, distance estimation, and uncertainty quantification. The framework achieves robust generalization under $$0-10$$ dB noise degradation with relative performance degradation below 12%, mean absolute error of $$0.73-1.12$$ m for controlled-condition distance estimation on datasets with ground-truth spatial annotatins (MAD, DCASE, MIMII), and $$1.24-1.68$$ m on ground-truth annotations from extended range intervals with aggregate MAE of 6.39m across all datasets inclusive of those with physics-simulation-derived labels and superior calibration ( $$ECE &lt; 0.04$$ on primary benchmarks). Furthermore, the model achieves superior calibration and rare-event detection compared to leading transformer-based baselines. These results demonstrate that multi-domain, physics-aware acoustic modeling yields substantial robustness and multi-task advantages over single-task classification baselines, particularly under adverse environmental conditions and for rare event categories, with implications for real-time deployment in defense monitoring, disaster response, and smart city surveillance.

Sutureless capsular bag–intraocular lens complex scleral fixation using iris retractors in eyes with crystalline lens subluxation: long-term outcome

Spatial Detection of Microsphere Polystyrene Plastics and Molecular Remodeling within a Full‐Body Mouse with MALDI Trapped Ion Mobility Mass Spectrometry Imaging

ABSTRACT Polystyrene (PS), a widely used synthetic polymer, breaks into micro‐ and nanoscale particles that can enter the body and accumulate in tissues. Conventional methods provide bulk chemical information, but lack spatial and metabolic context. Here, we use matrix‐assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) with trapped ion mobility spectrometry (TIMS) to localize PS across whole‐body murine sections and individual organs, allowing differentiation of PS chain lengths and associated metabolic shifts. Oral PS exposure produced clear organ‐specific lipid remodeling. In the stomach, increases in phosphatidylcholine (PC(30:2)), phosphatidic acid (PA(36:1)), and sphingomyelin (SM(34:1; O 2 )) suggest epithelial stress and barrier disruption. In the liver, PC(32:1) decreased, and higher PC(30:2) and PA(36:2) indicate impaired lipid export alongside compensatory adjustments to maintain membrane stability, with potential effects on systemic lipid balance. In the heart, reductions in SM(32:1; O 2 ), ether‐linked phosphatidic acid (PA(O‐34:1)), and hexosylceramide (HexCer(30:1; O 2 )) reflect disrupted sphingolipid and ether‐linked lipid species metabolism and altered lipid transport. Together, these findings reveal dynamic, tissue‐specific lipid responses to PS exposure. This study shows that MALDI TIMS MSI provides high‐resolution, label‐free mapping of PS and its metabolic footprint and can be extended to other low‐abundance synthetic compounds.

Quantitative and qualitative evaluation of residual deposits in implanted intravenous ports informs maintenance strategies

Two‐Dimensional Polymers as Modular Metal‐Free Solid‐State Catalysts for Efficient Sono‐Piezo‐Photocatalytic Hydrogen Peroxide Production

ABSTRACT Piezo‐photocatalysis synergistically integrates the features of piezocatalysis and photocatalysis, offering promising applications in environmental remediation, energy conversion, and biomedical therapy. Herein, we introduce modularly designed solid molecular catalysts (SMCs) comprised of metal‐free, polyaromatic, two‐dimensional polymers which offer an unprecedented level of control over piezopolarization—and consequently, piezo‐photocatalysis—through the rational design of structural motifs (diphenylpyridine or terpyridine) and backbone functionalities (methyl group, aliphatic amine antenna, or aromatic pyrrole ring). We demonstrate that piezopolarization, induced by ultrasound across a wide frequency range (35 kHz to 2.6 MHz), enables highly efficient sono‐piezo‐photocatalytic hydrogen peroxide production. The SMC AP5 featuring the terpyridine motif and pyrrole functionalization is the most active metal‐free piezo‐photocatalyst for hydrogen peroxide production under ambient conditions. Furthermore, the instantaneous on/off‐switchability of the sono‐piezo‐photocatalysts is shown, underscoring their potential for applications requiring spatiotemporal control over catalytic activity.

Myco-synthesized copper oxide nanoparticles as a sustainable bionanofungicide for managing Fusarium falciforme and enhancing potato productivity

Abstract Developing sustainable alternatives to chemical fungicides is imperative for sustainable agriculture. This study establishes a green nanotechnology approach by harnessing the biocatalytic potential of indigenous rhizosphere fungi to synthesize copper oxide nanoparticles (CuONPs). A consortium of soil-borne fungi, including Mucor circinelloides , was isolated from agricultural soils in Tanta, Egypt, and employed in the myco-synthesis of CuONPs. Comprehensive characterization confirmed the formation of crystalline, spherical nanoparticles (average size: 10.7 nm). The nanoparticles exhibited notable, dose-dependent antifungal activity in vitro, suppressing mycelial growth of the potato pathogen Fusarium falciforme by 33.95%, significantly outperforming bulk copper sulfate. Based on preliminary dose–response trials, 200 mg L − 1 was selected as the optimal concentration balancing antifungal efficacy and absence of phytotoxicity. In a greenhouse trial, foliar application of myco-synthesized CuONPs (200 mg L − 1 ) to F. falciforme -infected potato plants mitigated disease-induced growth inhibition, restored photosynthetic pigment levels, and rebalanced antioxidant enzyme systems, primarily enhancing catalase activity. Significantly, CuONPs supported protein homeostasis under stress and, most importantly, boosted tuber yield by up to 40% in healthy plants and appeared to restore productivity in infected ones. In contrast, the commercial fungicide showed phytotoxic effects on tuber initiation. This work establishes myco-synthesized CuONPs as a novel, dual-action agent for plant protection and growth promotion, offering a sustainable and effective strategy for integrated disease management.

Intermolecular Electrophilic Germylation Using GeCl ₄ and Al ₂ Cl ₆

ABSTRACT Electrophilic aromatic substitution is a textbook transformation for the lighter Group 14 elements. In contrast to acylation, alkylation, and silylation, electrophilic germylation is extremely underdeveloped. Herein we report the first effective intermolecular Germa–Friedel–Crafts reaction. Specifically, combining the key industrial precursor GeCl 4 , with Al 2 Cl 6 and an inexpensive hindered pyridine base enables electrophilic C‐H germylation of a range of arenes. The process can be applied for selective synthesis of either the mono‐ or the di‐aryl germanes, ArGeCl 3 and Ar 2 GeCl 2 , respectively. ArGeCl 3 are versatile intermediates that can be transformed in situ into the synthetically desirable ArGe(alkyl) 3 derivatives. Mechanistic and computational analysis support an S E Ar‐type process where Al 2 Cl 6 is the key halophilic activator that generates a germanium electrophile able to effect C–H germylation in combination with the base. Overall, this work demonstrates that a high‐yielding intermolecular Germa–Friedel–Crafts reaction is possible provided an appropriate Brønsted base is used.