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Engineering N-site isomerism in donor-acceptor covalent organic frameworks for efficient Fenton-like water purification
Abstract Covalent organic frameworks (COFs) have emerged as promising candidates for singlet oxygen ( 1 O 2 ) generation via peroxymonosulfate (PMS) activation, yet their structure-property-activity relationships remain poorly understood. Herein, three constitutionally isomeric donor-acceptor COFs (TF-22Bpy, TA-22Bpy and TA-33Bpy) were constructed via N-site isomeric engineering, which involved precisely modulation of the imine and pyridine nitrogen positions within the skeleton. This systematically structural engineering was undertaken to unravel the fundamental effects of regioisomerism on both the electronic structure and subsequent Fenton-like catalytic activity. Among the isomers, TA-33Bpy showed the best catalytic activity for PMS activation, exhibiting an observed rate constant ( k obs ) of 0.165 min −1 . This value is substantially higher than those of TF-22Bpy (0.013 min −1 ) and TA-22Bpy (0.052 min −1 ) by factors of 12.7 and 3.2, respectively. Mechanistic investigations indicate that direct PMS-COF interaction induces charge polarization within the donor-acceptor framework, generating localized electron-deficient and electron-enriched domains that promote the coupled redox steps required for selective ¹O₂ generation. This work identifies PMS-triggered charge polarization as a key determinant of PMS activation and offers a design principle for high-performance COF catalysts for water purification.
Nuclear localization of the glutaminyl-tRNA synthetase QARS reveals its role in DNA damage response in ovarian cancer
Standardized chronic disease management reduces comorbidity risk in China
Selective and autonomous generation of singlet oxygen for synergistic heavy metal-organic removal without energy input
Bubble-triggered built-in liquid metal-based galvanic cell for gas pipeline microleak detection
Modulation of habenula axon terminals supports action-outcome associations in larval zebrafish
Giant negative photomagnetism in an alterlattice
Abstract Photomagnetism enables optical control of spin order for engineering non-equilibrium phases, yet studies remain largely confined to ferromagnetic systems. Here, we introduce the alterlattice, an emergent structural motif realized in the cation- and anion-deficient perovskite oxide La 0.4 Ca 0.4 TiO 3–δ . The alterlattice is a three-dimensional alternately patterned superstructural network arising from structural competition, in which average lattice is described by Ibmm symmetry while local superstructure relaxes toward Cmmm symmetry. Within this motif, photo-induced antiferromagnetic correlations develop below 19 K. Under 473 nm illumination, the susceptibility of the alterlattice host decreases by 51.7% at 2 K and 1 T and rapidly recovers in the dark. The observed giant negative photomagnetism is associated with anisotropic strain fields that guide defect-mediated photocarrier transport, thereby driving the system from a spin-dilute paramagnetic state toward a short-range antiferromagnetic state with quasi-one-dimensional characteristics. The alterlattice opens a route to three-dimensional defect-topology engineering for non-equilibrium phases and antiferromagnetic spintronics.
Design of a live-attenuated bacterial vaccine using effector network engineering
Abstract Enteropathogenic Escherichia coli (EPEC) and Citrobacter rodentium (CR) are extracellular enteric attaching and effacing (A/E) pathogens of humans and mice, respectively. Their virulence relies on intimate bacterial attachment and a network of type III secretion system effectors. Here, through systematic reduction and redesign of the effector network in CR, we develop an attenuated strain, CRV (CR Vaccine), encoding a subset of ten effectors. CRV colonises C57BL/6 mice ~100-fold lower than wild type CR (CR WT ) without causing overt pathogenesis. Moreover, C3H/HeN mice, which succumb to CR WT infection, survive CRV challenge. Vaccination with CRV confers protection against subsequent CR WT infection in both mouse strains. Serological analysis reveals a repertoire of dominant CR antigens, including the O-antigen, the virulence factors intimin, EspA and Tir and the outer membrane proteins Lpp, OmpA, MetQ and CARC (an AIDA-like autotransporter). We show that CR WT and CRV immunisation elicits comparable B cell and antibody responses, which is contingent on intimate bacterial attachment. A corresponding EPEC strain ( E. coli Vaccine, ECV) effectively colonises epithelial cells in a gut-on-chip model. These findings establish effector network minimisation as a generalisable strategy for rational bacterial attenuation and live-attenuated vaccine design.
Decoupling ferroelectric polarization and charge transport for thermally robust polymer dielectric energy storage
Heat stress promotes pre-tRNA capping to modulate cap-dependent translation in Saccharomyces cerevisiae
Iron Oxide Photoanode for Glycerol-Assisted Hydrogen Production at 8.87 mA cm–2
Systematic profiling of growth interactions in human gut microbiome species
Abstract Microbial interactions shape the composition and stability of the human gut microbiome. Yet, few studies have systematically investigated species-species growth interactions and the mechanisms behind these. Here we show that among 36 representative gut bacterial strains, when two species interact, the interactions are mostly inhibitory. To provide biological insight into specific interactions, we further investigate the basis of a positive interaction, showing that Clostridium perfringens promotes the growth of Mediterraneibacter gnavus through extracellular vesicles. Additionally, we identify Veillonella parvula as a species capable of modulating environmental pH, thereby enabling the growth of Parabacteroides merdae , a strain highly sensitive to acidic conditions. This pH-increasing effect is enhanced by guanine supplementation and persists in multi-species communities containing different pH-lowering strains from diverse bacterial phyla. Although V. parvula is commonly present in human gut microbiomes, it is generally found at low levels. Given the spatial organization of bacteria in the gut, the local pH modulation by V. parvula might support the growth of acid-sensitive strains. Overall, the comprehensive dataset and mechanistic insights presented here provide a starting point to predict microbiome composition by integrating growth interactions.
In situ electron microscopy of LaNiO3 transformation during reduction and methane dry reforming
Abstract By in situ electron microscopy we show the intermediate phase formation during decomposition of LaNiO 3 , a model methane dry reforming (DRM) catalyst, under different gas atmospheres. By combining dark- and bright-field imaging with secondary-electron contrast and operando electronic structure characterization, we localize the coupled formation of Ni(O) particles and La 2 NiO 4 as key intermediates under DRM operation preceding full decomposition into metallic Ni and La 2 O 3 . Reduced and bar-level reactant partial pressures enable detailed observation of early decomposition stages. Ni particles formed in vacuum or DRM mixtures undergo transient surface oxidation by lattice oxygen, while highly dynamic Ni particles result from hydrogen reduction. At high temperatures, concurrent Ni formation, LaNiO 3 -to-La 2 NiO 4 transitions, Ostwald ripening, and particle fragmentation/agglomeration govern the dynamics. DRM exposure of reduction-formed Ni leads to rapid oxidation to sintering-resistant NiO with size-dependent dissolution/agglomeration characteristics. As CO 2 cannot directly oxidize Ni here, oxygen migration from the perovskite bulk drives this transient, DRM-detrimental NiO formation.
Low curvature combined with high amorphization improves SERS sensitivity of semiconducting Rh–Se mesoporous nanospheres toward non-adsorbing resistant pollutants
Near-infrared circularly polarized electroluminescence from axially chiral diplatinum(II) phosphors
DNTTIP2 coordinates RNA exosome activities to ensure fidelity of human ribosome assembly
Abstract The RNA exosome-associated helicase Mtr4/MTR4 (yeast/human) is recruited by adaptor proteins bearing Arch-Interacting Motifs (AIMs) to selectively degrade RNA substrates. Although the exosome targets diverse RNAs, only a few adaptors have been identified. Here, we extend the inventory of human adaptors to include a pre-tRNA splicing-ligase complex component, a spliceosome-associated factor, and DNTTIP2, a constituent of the small ribosomal subunit (40S) precursor, the 90S pre-ribosome. Structure-guided studies reveal how the DNTTIP2 AIM -docked processive exosome core and its associated distributive exonuclease EXOSC10, which contact distant sites on the 90S pre-ribosome, cooperate to degrade part of the 5′-external transcribed spacer (5’-ETS), a key RNA scaffold that coordinates early 40S assembly. By contrast, productive pre-ribosomal RNA trimming within the 90S pre-ribosome necessitates EXOSC10, which safeguards against uncontrolled processive degradation by the DNTTIP2 AIM -docked exosome core. We propose that multivalent contacts provide a mechanistic framework by which the RNA exosome coordinates its distinct enzymatic activities, ensuring selective processing and surveillance during ribonucleoprotein particle maturation.
Non-canonical pore architecture underlies constitutive gating of human retinal TRPM1
Facile mechanical refinement of sulfide solid electrolytes for stable all-solid-state Li metal batteries
Trap-induced white circularly polarized persistent luminescence from a host-guest molecular system
Abstract Circularly polarized luminescence (CPL), which encodes non-replicable optical information in the characteristics of chirality, wavelength, and time, holds significant promise for advanced information technologies. However, effective strategies for systematically regulating multiple optical properties remain elusive. Herein, we report a general approach that imparts hour-level dual-band persistent luminescence to CPL materials through the introduction of trap states into an organic host-guest molecular system. The electrons released from traps repopulate both the singlet and triplet states of the chiral guest molecules, producing dual-band white circularly polarized persistent luminescence for 4 h at room temperature. Systematic characterization reveals that two different chiral configurations leave the trap depth basically unaltered, while conferring pronounced CPL activity on these composites with a maximum luminescence dissymmetry factor g lum of 1.6 × 10 −3 /−2.3 × 10 −3 . Leveraging these characteristics, we present a proof-of-concept demonstration of warm-white circularly polarized persistent luminescence materials for Morse-code encryption and multimodal information storage.