Browse Articles

ZnF-UBP domains regulate deubiquitinase activity by relieving ubiquitin product inhibition

Skeletal Reorganization of Cycloalkylamines Into Angular Azatetracyclic Scaffolds

ABSTRACT The efficient, single‐step construction of angular azatetracyclic frameworks bearing vicinal quaternary stereocenters remains a formidable challenge in synthetic chemistry. Herein, we disclose the first borane‐catalyzed cascade reorganization of N ‐cycloalkylidenyl (CAD)‐substituted aryl cycloalkylamines that enables rapid access to these architectures. Initiated by B(C 6 F 5 ) 3 ‐mediated α ‐hydride abstraction, the reaction proceeds through an aza‐6π electrocyclization and two successive ring expansions, followed by hydride rebound, to deliver densely functionalized angular/fused azatetracycles with high diastereoselectivity. This designed cascade forges multiple C–C bonds and stereocenters in a single operation and exhibits broad substrate scope and excellent efficiency. Detailed mechanistic investigations, combining experimental results and DFT calculations, support the proposed sequence of hydride abstraction, cyclization, double ring expansion, and hydride rebound.

MTDRA-Net: graph-temporal neural network for dynamic evaluation of college students’ responsibility

Consequences of agricultural deforestation and subsequent afforestation on soil biodiversity and ecosystem multifunctionality

Sulfur‐to‐Metal Single‐Atom Editing of a Thiourea Self‐Assembled Monolayer into an Adatom‐Bound N‐Heterocyclic Carbene Monolayer on Coinage Metal Surfaces

ABSTRACT N‐Heterocyclic carbene (NHC) self‐assembled monolayers (SAMs) are emerging as robust and versatile surface ligands, yet their direct on‐surface construction with atomic precision remains elusive. Here, we report a reagent‐free, thermally driven on‐surface strategy for single‐atom editing, providing an alternative to convert a heteroatom‐anchored SAM into a functional NHC layer. N‐Heterocyclic thiourea (NHT) with carefully chosen substituents undergoes a S‐to‐metal adatom exchange, yielding adatom‐bound NHC on coinage metal surfaces. Using low‐temperature scanning tunneling microscopy (LT‐STM), synchrotron‐radiation X‐ray photoelectron spectroscopy (SR‐XPS), time of flight secondary ion mass spectrometry (ToF‐SIMS) and density functional theory (DFT), we identify two distinct classes of SAMs: (i) NHT‐SAM, in which sulfur coordinates to the metal surface and (ii) NHC‐SAM, characterized by M─C σ ‐bonds between the carbene center and a surface adatom. NHT undergoes a clean SAM‐to‐SAM conversion, achieving covalent single‐atom editing within an intact monolayer. DFT calculations show this transformation is energetically favorable and highly tunable by substrates and N‐substituents, establishing a general framework for atom‐precise molecular editing at surfaces.

An end-to-end deep learning pipeline for urban noise monitoring with spatiotemporal analysis

Coexistence of high temperature superconductivity and antiferromagnetic order in a cuprate with multiple hole Fermi pockets

Solar‐Driven CO ₂ ‐Mediated Upcycling of Waste Plastics Into Value‐Added Syngas and Carbon Nanotubes

ABSTRACT Plastics and CO 2 are two major waste carbon resources, and their management and recycling are attracting increasing attention. CO 2 ‐mediated plastic upcycling represents a promising strategy for the simultaneous transformation of both wastes, yet it still suffers from high energy demand, low efficiency, and limited applicability to diverse plastics. Here, we report a solar‐driven photothermal strategy that enables the efficient and energy‐saving CO 2 ‐mediated reforming of various plastics, including polyolefins, polyesters, copolymers, and their mixtures, into high‐value syngas and carbon nanotubes (CNTs). The process achieves a syngas yield of 165.6 mmol g cat −1 h −1 , an order of magnitude higher than that of conventional thermocatalysis. Within this system, CO 2 acts not only as an oxidant that consumes the hydrogen species released during plastic dehydrogenation, thereby enhancing efficiency and suppressing methanation but also as a carbon feedstock that directly contributes to both gaseous and solid products. This study provides a powerful solution for the valorization of complex plastic wastes and greenhouse gases and offers new insights into solar‐driven chemical transformations toward a circular carbon economy, while further optimization of the H 2 /CO ratio may expand its compatibility with specific downstream applications.

Associations between postoperative serum omics-derived proteins and aggressive clinicopathological features of papillary thyroid cancer

Bootstrapping multimodal large language model with medical knowledge for automatic esophagogastroduodenoscopy diagnosis and reporting

Flavin Catalysts in Organic Synthesis

ABSTRACT Flavin cofactors are nature's all‐rounders with several essential roles in the active site of flavin‐dependent enzymes. These flavoenzymes display an astonishingly broad activity spectrum, which also translates to the organic laboratory. In synthetic chemistry, flavin catalysis is now an integral part of several organocatalytic and photochemical methods with applications ranging from total synthesis to biocompatible photoproximity labeling. Flavins take a unique position in the field: they are easily accessible through synthesis or biochemical methods, while additionally exhibiting orthogonal reactivity compared to other (organo‐)catalysts. Several flavin‐mediated organic reactions were developed in a biomimetic fashion guided by extensive literature on enzymatic mechanisms. Additionally, flavin modification to tailored catalysts enabled desired non‐natural transformations. This minireview gives an overview of and highlights the different key chemical transformations achieved with flavin catalysis in synthetic organic chemistry with a focus on photochemical oxidation and reduction, sensitization, oxygenation, and the activation of substrates by reversible covalent bond formation. The individual requirements for achieving specific flavin reactivity are illustrated based on example reactions. Finally, remaining challenges in the field of flavin catalysis are identified.

Hurricane exposure, structural vulnerability, and insurance gaps drive property damage after superstorm sandy

Repetitive neuronal activation regulates cellular maturation state via nuclear reprogramming

Abstract Neural stimulation, such as electroconvulsive therapy (ECT) and repetitive transcranial magnetic stimulation (rTMS), is highly effective clinical intervention for a broad spectrum of psychiatric disorders, including depression and schizophrenia. However, their mechanism of action at the cellular level remains poorly understood. Here, we model ECT with repeated optogenetic neuronal stimulation in the mouse dentate gyrus, and observe ECT-relevant behavioral changes, including decreased depression-like behavior and increased locomotor activity. At the cellular level, we identify dematuration to a long-term stable state, persisting for more than one month, defined by changes in nuclear structure, gene expression patterns resembling the G 2 /M phase of the cell cycle, and altered neural coding of navigational information. Moreover, knockout of the G 2 /M master regulator Cyclin B attenuates some of behavioral and cellular effects. These findings demonstrate that chronically-repeated brain stimulation triggers plasticity of the cellular state, revealing a form of stimulus-regulated nuclear reprogramming with potential clinical utility.

Endogenous Redox‐Sensitive UV Absorbers Enable Efficient and Stable Full Air‐Processed Perovskite Solar Cells

ABSTRACT Perovskite solar cells (PSCs) face significant obstacles to commercialization due to the rapid degradation of perovskite materials under non‐equilibrium conditions, especially under ultraviolet (UV) radiation from sunlight. To address this critical challenge, an endogenous redox‐sensitive UV absorber, 2,2″‐Thiobis‐(4‐tert‐octylphenoxy)‐butylamine nickel (TTOB), was introduced into the perovskite precursor solution. The integrated TTOB enhances the efficiency and stability of PSCs through multiple synergistic functions, including superior UV shielding capability and sustained chemical passivation effects for ongoing defect repair. Ultimately, the resultant device fabricated entirely in air achieved a best‐in‐class power conversion efficiency (PCE) of 25.24%, accompanied by greatly improved stability under various environmental conditions, with retaining approximately 86% of initial efficiency after 1,000 h of continuous UV exposure, about 87% after 40 days of outdoor real‐time storage, and over 80% after 1430 h of continuous illumination. This innovative UV protection strategy with endogenous redox‐sensitive offers transformative potential for the large‐scale application of perovskite photovoltaic technology during actual outdoor operation.

Composite metabolic indices for the assessment of early biochemical and metabolic alterations in Iraqi children and adolescents with type 1 diabetes: an exploratory case–control study

Versatile Glycan Probes for Multiplatform Investigation of Glycan Interactions with Proteins, Viruses, and Cells

Abstract Glycan-mediated interactions are vital to development, microbial colonisation, immune signalling, and cancer progression. Glycan microarrays have revolutionised glycobiology by enabling high-throughput analysis of these complex interactions, supported by techniques that reveal kinetics and dynamics in solution or at the cellular level. We introduce multifunctional glycan probes based on a tri-functional Fmoc-Amino-Azido (FAA) linker, enabling multi-platform investigation of glycan-mediated interactions. These FAA probes support glycan presentation on both covalent and non-covalent array platforms, allowing direct comparison of glycan recognition by diverse proteins. Notably, certain viral adhesins and immune lectins show a preference for the non-covalent platform. The azido group allows further functionalisation via ‘click chemistry’, enabling biotinylation for immobilisation on bio-layer interferometry biosensors for influenza virus binding, or fluorescent tagging for flow cytometry analysis of glycan-lectin interactions on cells. These versatile probes offer a unified platform for in-depth interrogation of glycan interactions using complementary approaches, with strong potential to advance glycan-based diagnostics and therapeutics.

Interface Local‐Alkalinity Engineering for Enhanced Dehydrogenation Catalysis in Neutral Media

ABSTRACT Hydrous hydrazine has emerged as a promising liquid‐phase hydrogen storage material, but its practical application has long been constrained by sluggish reaction kinetics under neutral conditions. Drawing inspiration from interfacial engineering, we designed a NiPt‐Ni(OH) 2 interface that regulates the local microenvironment, enabling highly efficient hydrogen production from hydrous hydrazine under neutral conditions at room temperature. At the interfaces, strong electronic coupling is established and the adsorption of hydrazine is also altered. The resulting NiPt‐Ni(OH) 2 catalyst achieves a remarkable apparent turnover frequency of 310.7 h −1 at 298 K, representing the highest performance reported to date for hydrous hydrazine dehydrogenation without external base added during catalysis. Combined spectroscopic analysis and density functional theory calculations reveal that the interfacial Ni(OH) 2 not only donates electrons to the NiPt alloy, modulating its electronic structure but also provides Brønsted basic sites that promote a favorable linear adsorption configuration of hydrazine. This dual electronic and chemical modulation lowers the energy barrier for dehydrogenation and accelerates hydrogen evolution kinetics. Our findings establish a generalizable interface engineering paradigm for catalytic enhancement under mild conditions without relying on external alkaline additives.

Docosahexaenoic acid attenuates cisplatin nephrotoxicity by restoring mitophagy

Core elements play distinct roles in promoter birth and transcriptional regulation

CeO <i> _x </i> ‐Induced Spatial and Electronic Modulation for General Direct Oxo Coupling in Transition Metal Hydroxides

ABSTRACT Electrochemical water splitting has emerged as a sustainable paradigm for hydrogen generation, where sluggish kinetics of the oxygen evolution reaction (OER) catalyzed by transition metal‐based materials remain the critical bottleneck. Herein, we present a strategy that anchors CeO x nanoparticles (∼2 nm) onto two‐dimensional Ni(OH) 2 nanosheets, enabling dual modulation of spatial configuration and electronic states to accelerate O–O coupling. Spatially, interfacial lattice distortion between CeO x and Ni(OH) 2 optimizes Ni–Ni dual‐metal sites with reduced interatomic spacing. Electronically, dynamic modulation through reversible Ce 3+ /Ce 4+ redox cycling positions Ce as an electronic regulation hub, stabilizing Ni species at the catalytically favorable +3 oxidation state through Ce─O─Ni interactions. This synergistic effect shifts the pathway from adsorbate evolution mechanism (AEM) to oxide pathway mechanism (OPM). The prepared CeO x @Ni(OH) 2 achieves an overpotential of 152 mV at 10 mA cm −2 and operates continuously over 2000 h with limited performance decay. When integrated into an alkaline anion exchange membrane water electrolyzer (AEMWE), it requires 1.91 V to attain 1 A cm −2 and maintains stable operation for 450 h. This OPM activation strategy shows potential applicability across CeO x ‐loaded transition metal hydroxides, including Ni(OH) 2 , Co(OH) 2 , NiCo, and NiFe layered double hydroxides, offering a promising approach for alkaline OER enhancement.