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Diphenoquinone‐Based Covalent Organic Frameworks for Efficient H <sub>2</sub> O <sub>2</sub> Production via Photothermal Synergistic Catalysis
ABSTRACT Covalent organic frameworks (COFs) have recently attracted tremendous attention as advanced photocatalytic platforms for H 2 O 2 production from oxygen and water. However, their intrinsic catalytic activity and solar‐to‐chemical energy conversion efficiency are unsatisfactory for practical applications. In this work, a photothermal synergistic catalysis strategy for improving H 2 O 2 production of photocatalysts was proposed. As a proof of concept, two novel diphenoquinone‐based frameworks (COF‐JLU240 and COF‐JLU241) with donor‐acceptor character were constructed for the first time. These frameworks feature broad light harvesting, inherent photoelectric properties, and superior photothermal conversion efficiency. Under the illumination of a 660 nm laser with 100 mW cm −2 , the temperature of COF‐JLU241 drastically increased from 26.5°C to 184.6°C within 1 min. Importantly, COF‐JLU241 exhibits an impressive H 2 O 2 production rate of 4894.9 µmol h − 1 g − 1 in pure water under simulated sunlight, which is 3.86‐fold higher than that obtained at the conventional temperature (23°C). Experimental and theoretical studies revealed that increasing the reaction temperature via photothermal effect can effectively promote the separation and transport of photogenerated charges and reduce the energy barrier for surface reactions. This finding contributes a fascinating photothermal synergy strategy for increasing the conversion of solar into chemical energy and broadens the scope of COF‐based photocatalysts.
Metal organic framework functionalized reflective tapered fibre-optic surface plasmon resonance based refractometer for vapor sensing
Abstract Metal-organic frameworks (MOFs), such as ZIF-8, have been extensively studied for their gas adsorption and chemical sensing capabilities owing to their high surface area, porosity, and tunable host-guest interactions. The adsorption of a guest molecule modifies the effective refractive index of ZIF-8 through pore-filling effects, rendering it appropriate for optical sensing. In the present study, we investigate the design of a reflective tip-based tapered fiber optic surface plasmon resonance (FO-SPR) platform functionalized with a ZIF-8 absorbing layer for the detection of chemical vapors. Experimentally measured, analyte-dependent refractive index changes of ZIF-8 are integrated into a Transfer Matrix Method (TMM) based reflective tapered FO-SPR model to systematically evaluate the influence of taper ratio on resonance wavelength, sensitivity, spectral broadening, and figure of merit for different vapor analytes. The analyte-dependent response towards tetrahydrofuran (THF), ethanol, and dimethylformamide (DMF) is analysed in terms of the refractometric modulation characteristics of ZIF-8 using the SPR transduction mechanism. To the best of our knowledge, this study constitutes the first theoretical investigation of MOF pore-filling dynamics within a reflective-tapered FO-SPR configuration. The sensor performance enhances significantly as the taper diameter decreases from 600 to 200 μm with sensitivity increasing from 9.38 to 10.76 nm/Volume Factor for THF and from 4.83 to 5.69 nm/Volume Factor for DMF. The operating range of the sensor is governed by the effective refractive index tunability of the ZIF-8 layer, which varies from 1.355 to 1.421, ensuring conditions necessary for SPR excitation relative to the fiber core. These results establish a fundamental framework for optical refractometric vapour sensing and provide practical design guidelines for MOF-functionalized tapered FO-SPR platforms.
Retraction Note: Heterozygous deletion of chromosome 17p renders prostate cancer vulnerable to inhibition of RNA polymerase II
Evaluation of fluorimetric assay conditions for measuring leucine aminopeptidase activity in soils
Leucine aminopeptidase (LAP) plays a crucial role in the hydrolysis of proteinaceous nitrogen in soils. However, existing studies use varying conditions in the fluorimetric assay of soil LAP, which hinders cross-study comparison of the measured activities. Using one purified enzyme and three soils of contrasting properties, we examined how LAP activity responded to variations in assay conditions including buffer pH, substrate (L-leucine-7-amido-4-methylcoumarin) concentration, temperature, incubation time, soil amount, and metal ion concentrations. We found that: (1) the optimal pH for LAP activity ranged from 7 to 9; (2) a substrate concentration of 250 μM was necessary to achieve zero-order reaction kinetics; (3) LAP activity increased as the temperature rose from 10 to 40 °C, with a Q 10 value between 1.63 and 2.45; (4) the rate of the enzymatic reaction remained stable for at least 3 hours; (5) measured activity decreased as the amount of soil used for homogenate preparation increased from 0.5 to 2.0 g; and (6) the activity of LAP was not substantially stimulated by the addition of metal ions, suggesting that a metal cofactor is not needed for the fluorimetric assay of LAP. We also compared the behaviors of LAP with those of the colorimetrically measured arylamidase that catalyze the release of an N-terminal amino acid from peptides, amides, or arylamides, and found that they may represent the same group of soil enzymes. Our findings may help standardize the assay protocol for soil LAP, which is essential for conducting meta-analysis of enzyme activities measured across different studies.
Probing Into Asymmetric Dearomatizing Photocycloadditions of 2‐Naphthalene Derivatives With Alkenes: [2 + 2] and [4 + 2] Pathways
ABSTRACT Catalytic dearomative photocycloaddition stands as one of the most powerful strategies for constructing highly complex, three‐dimensional polycyclic scaffolds from readily accessible planar aromatic precursors. However, achieving asymmetric variants of these transformations with simple alkenes remains a formidable challenge, as it demands precise control over regio‐, diastereo‐, and enantioselectivity. Herein, we report asymmetric dearomatizing [2 + 2] and [4 + 2] photocycloadditions of 2‐naphthalene derivatives by chiral terbium(III)/ N,N' ‐dioxide complexes, wherein a pronounced ligand‐acceleration effect is operative. The selectivity between the two pathways is governed by reaction temperature, alkene stoichiometry, and reaction time, thereby enabling the divergent synthesis of chiral cyclobutane‐fused adducts (46 examples, up to 99% yield, > 19:1 dr, 99% ee) and bridged adducts (41 examples, up to 99% yield, up to 12:1 dr, 99% ee) with high efficiency. Notably, both cycloaddition manifolds accommodate terminal and internal olefins. Mechanistic investigations elucidate the origin of the ligand‐acceleration effect and establish a kinetic basis for ortho ‐selectivity in the [2 + 2] pathway and a thermodynamic basis for para ‐selectivity in the [4 + 2] pathway. Density functional theory calculations further rationalize the competitive interplay between [2 + 2] and [4 + 2] cycloadditions and provide insight into the stereochemical outcome.
Chronic kidney disease is associated with greater post-stroke cognitive decline in a nationwide longitudinal cohort
DeepTriage-CN: integrating clinical text with vital signs for emergency department admission prediction in an aging population
Abstract Emergency department (ED) triage of older adults is challenging because standard early warning scores are often insensitive to atypical presentations. We developed DeepTriage-CN, a late-fusion framework combining frozen BERT-Chinese embeddings of nurse-recorded chief complaints with structured triage vital signs via an XGBoost classifier. The model was trained on 8000 adult ED visits and validated temporally on 2000 independent encounters. DeepTriage-CN achieved an AUROC of 0.865, statistically indistinguishable from the tabular deep-learning comparator TabNet (0.867; DeLong p = 0.42). The multimodal model significantly outperformed traditional clinical scores (NEWS2, 0.772; ESI, 0.760) and vitals-only baselines (XGBoost, 0.858; all DeLong p < 0.001). In older patients (age ≥ 65 years), the model maintained an AUROC of 0.852 versus 0.710 for ESI and 0.741 for NEWS2, though performance remained comparable to TabNet (0.835; p = 0.21). Under simulated 30% informative missingness with Gaussian noise, DeepTriage-CN retained 95.4% of its baseline AUROC compared with 83.3% for TabNet and 82.8% for vitals-only XGBoost. However, at the Youden-optimal classification threshold (0.28), positive predictive value was 0.50, meaning one in every two generated alerts is a false positive. These findings identify a specific operational envelope in which the multimodal approach confers situational advantage—primarily when structured physiological data are degraded—while confirming that text embeddings provide no statistically significant incremental discriminative gain over optimized tabular deep-learning architectures in the general population. Prospective multicenter validation with clinically actionable endpoints is required before this framework can inform ED triage practice.
Molecular‐Level π‐Stacking Engineering in Dative B←N Frameworks for Superior Photocatalytic H <sub>2</sub> O <sub>2</sub> Production
ABSTRACT The photocatalytic synthesis of hydrogen peroxide (H 2 O 2 ) from O 2 and H 2 O represents a sustainable alternative to the energy‐intensive anthraquinone process. However, achieving efficient photocatalysis requires precise control over structure–activity relationships, which remains a significant challenge. Herein, we report a molecular engineering strategy that leverages precise tuning of intermolecular π‐stacking in three single‐crystalline dative B←N frameworks (BNF‐75, ‐76, and ‐77). By systematically modulating the planarity of the B‐acceptors, we achieved a progressive decrease in the root‐mean‐square deviation (RMSD) of the B‐acceptors from 0.463 Å in BNF‐75 to 0.201 Å in BNF‐77. The BNF‐77 exhibits broadened visible‐light absorption, enhanced charge separation and transport, and an outstanding H 2 O 2 production rate of 5684.6 µmol·g −1 ·h −1 under visible light without sacrificial agents or metal cocatalysts (λ > 420 nm). Simple mechanical grinding for particle‐size reduction further elevates the rate to a remarkable 9451.0 µmol·g −1 ·h −1 , positioning BNF‐77 among the top‐performing crystalline photocatalysts based on dative B←N bonds. Integrated mechanistic studies reveal a synergistic mechanism: the dative B←N bond extends light harvesting and promotes charge separation, while the engineered tight π‐stacking constructs efficient charge‐transport highways and facilitates the two‐electron oxygen reduction reaction (ORR) pathway, with superoxide radicals (•O 2 − ) as the key intermediate.
A two-stage cascaded purification framework for backdoored object detectors via backdoor feature suppression
Dual‐Interface Nanopore Array Sensor Revealing the Synergistic Oscillations of Lactate Efflux in Cancer Cells
ABSTRACT Lactate is a key substrate and signaling molecule in tumor metabolism. Its efflux from cancer cells acidifies the tumor microenvironment and reflects the energy metabolic states. Clarifying the lactate efflux is crucial for understanding how cancer cells rapidly adjust energy metabolism and cooperatively adapt to stress. However, the endogenous reactive oxygen species (ROS) of cancer cells severely interfere with oxidase‐based lactate sensor signals and hinder quantitative analysis of lactate efflux. To address this challenge, we developed a dual‐interface nanopore array sensor (DINAS) that integrates an anti‐ROS interface and a lactate sensing interface. When cultured on the sensor, the cancer cells release ROS and lactate that diffuse along the nanopores: the outer anti‐ROS interface electrochemically removes ROS, while the inner sensing interface monitors lactate efflux. Using this dual‐interface sensor design, we disclosed that the drug‐induced lactate efflux exhibits a time‐dependent “rise‐then‐fall” behavior, reflecting the energy metabolic reprogramming. Moreover, we unexpectedly observed a synergistic oscillation in lactate efflux at the cell population level. This oscillation might indicate a connexins‐related coordination of lactate homeostasis between a population of cancer cells, and its discovery may provide new strategies for future precision anticancer therapies targeting the regulating ability of lactate metabolism.
Involvement of the IL-27/p38 MAPK/PGC-1α pathway in sleeve gastrectomy-induced metabolic improvement
Abstract Sleeve gastrectomy (SG) effectively improves metabolic disorders in individuals with obesity and type 2 diabetes (T2DM), but its molecular mechanism remains unclear. Interleukin 27 (IL-27) improves obesity, insulin resistance and white adipose tissue browning; however, its role in SG-mediated metabolic improvement is unconfirmed. This study aimed to explore the role of IL-27 in metabolic disorders improved by SG in obese T2DM rats. Obese T2DM rats were established and randomly divided into an SG group and a sham operation (control) group. Body weight, food intake, fasting blood glucose levels and insulin resistance indicators were dynamically monitored. Enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qRT‒PCR) and immunohistochemistry were used to measure the levels of IL-27 and adiponectin in rat plasma, as well as the expression levels of related molecules in epididymal white adipose tissue (eWAT) and inguinal white adipose tissue (iWAT); 3T3-L1 adipocyte experiments were performed to clarify the regulatory relationship between IL-27 and adiponectin. Compared with the control group, SG significantly reduced body weight, food intake, fasting blood glucose, and insulin resistance in obese T2DM rats (all P < 0.05); it also significantly increased the IL-27 levels in plasma, eWAT, and iWAT, and upregulated the expression of the IL-27 receptor (IL-27Rα) in eWAT, and the expression of p38 mitogen-activated protein kinase (p38 MAPK), peroxisome proliferator-activated receptor α (PPAR-α), peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), and uncoupling protein 1 (UCP-1) in eWAT, as well as UCP-1 in iWAT (all P < 0.05). In vivo experiments revealed a significant positive correlation between IL-27 and adiponectin levels ( P < 0.05); in vitro experiments confirmed that IL-27 directly promoted adiponectin expression, whereas adiponectin did not significantly affect IL-27 expression ( P > 0.05). SG is associated with elevated IL-27 levels and activation of the eWAT p38 MAPK-PGC-1α pathway in obese T2DM rats, accompanied by improved metabolic parameters, suggesting that IL-27 may play a role in SG-induced metabolic improvement.
Hydrogen‐Bond‐Networked Robust Binder Enabling Long‐Cycling Sulfide‐Based All‐Solid‐State Lithium Batteries
ABSTRACT Wet processing is promising for scalable manufacture of sulfide‐based all‐solid‐state lithium batteries (ASSBs), but it demands binders compatible with low‐polarity solvents and sulfides while enabling thin sulfide solid electrolyte (SSE) films (≤ 30 µm) and high‐loading composite cathodes (≥ 30 mg cm −2 ). To address these, we present a dynamic hydrogen bonding‐empowered robust polymer (denoted as PNO) binder via soft‐hard segment synergism design. In the PNO binder, the polybutadiene‐based soft segments retain easy processability of SSE films and composite cathodes, while carbamate motif‐containing hard segments improve the mechanical strength of them mainly via forming dynamic hydrogen bonding interactions not only among adjacent PNO chains but also between PNO chains and the surface of sulfide or cathode particles. The breaking and reforming of hydrogen bonds enable effective stress dissipation, thereby maintaining the structural stability of both SSE films and composite cathodes during processing and battery cycling. Benefiting from these, ASSBs assembled with PNO binder‐based LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathodes and Li 6 PS 5 Cl films exhibit outstanding cycling stability, which compares favorably with recently reported sulfide‐based ASSBs. This work highlights a soft‐hard segment synergism binder design strategy that overcomes the bottleneck in wet processing of practical ASSBs, conducive to accelerating the scale‐up production of advanced sulfide‐based ASSBs.
A video statistics-aware sequential recommendation model with multi-behavior feedback for short-video recommendation
Hydrogen‐Bond Anchored Channel‐Microenvironment Engineering in Polymer Membranes for Efficient Lithium Extraction
ABSTRACT The creation of synthetic membranes that mimic the high selectivity and flux of biological ion channels remains a major challenge in separation science. Precise control over chemical microenvironment within sub‐nanometer pores is critical but notoriously difficult to achieve in scalable materials like amorphous polymers. Here we report a strategy for engineering the microenvironments of confined channels in a polymer of intrinsic microporosity (PIM) by using hydrogen bonding to uniformly anchor oligoether chains onto the pore walls. The enhanced confinement effect resulting from this anchoring increases steric limitation for larger ions (e.g., Mg 2+ ) and strengthens their ion‐channel interactions. Concurrently, the uniformly distributed oligoether chains establish a synergistic transport pathway for small ions (e.g., Li + ). The resulting membrane exhibits exceptionally high selectivity for monovalent ions over divalent ions (Li + /Mg 2+ selectivity of >270) while maintaining a high Li + flux (>0.6 mol m −2 h −1 )—an order of magnitude improvement compared to state‐of‐the‐art polymeric membranes. When deployed for direct lithium extraction from salt‐lake brine, the membrane achieves a lithium recovery rate of 268 g m −2 day −1 and low energy consumption (7.26 Wh g Li −1 ).
Towards robot-assisted magnetic particle imaging for mobile point-of-care (neuro)vascular applications
Abstract Rapid diagnosis, timely treatment, and continuous monitoring are essential for improving outcomes in neurovascular diseases (time=brain). Such point-of-care applications, however, require imaging to be conducted in dynamic and often confined spaces. While magnetic particle imaging (MPI) shows preclinical promise for fast (neuro)vascular imaging, it relies on complex and restricted imaging gantries. Here, we present a unique gantry-free robot-assisted MPI strategy (Robotic MPI) that is ‘portable’. Using permanent magnets, Hall sensors and correction coils, we developed a single-sided detector with a detection threshold of ~ 5 µg iron-containing contrast agent at the detector surface. Robot-assisted positioning and pose tracking, combined with a dedicated maximum likelihood expectation-maximization-based reconstruction algorithm, translates detector signals into tomographic images with a spatial resolvability of 7 mm (visually evaluated at an imaging depth of ~ 5 mm). Surface imaging (SI) provided anatomical reference, delivering hybrid MPI/SI scans. Robotic-MPI’s ability to visualize 3D (neuro)vasculature in a phantom model, highlights the system’s potential for next-generation, portable vascular imaging solutions.
Controllable Electrocatalytic Synthesis of Aldehydes From Alcohols on Co‐Based Catalysts: A Redox Cycling‐Mediated Indirect Oxidation Mechanism
ABSTRACT The electrocatalytic oxidation of biomass‐derived alcohols offers a green and sustainable route for the preparation of aldehydes, which, however, still faces great challenges such as uncontrollable deep oxidation, preferentially to organic acids, complex and harsh reaction conditions, and the necessitation of high‐cost noble‐metal‐based catalysts. Herein, a Co 3+ /Co 4+ ‐mediated indirect oxidation mechanism has been demonstrated for the controllable and selective oxidation of alcohols to aldehydes under neutral conditions. As a proof‐of‐concept, we successfully developed a CeO 2 /Co 3 O 4 /CC catalyst for oxidizing ethylene glycol to glycolaldehyde dimer, which achieves a favorably high Faradaic efficiency of 94.4% and 99.9% selectivity, even standing out from previously reported noble‐metal‐based catalysts. Detailed mechanistic studies reveal that the reaction is driven by the redox cycling of the Co 3+ /Co 4+ redox couple, and the heterojunction interface between CeO 2 and Co 3 O 4 effectively elevates the Co 3+ content in the catalyst, thereby effectively facilitating active Co 4+ species generation as the rate‐determining step and remarkably enhancing the electrocatalytic alcohol oxidation performance. Overall, the proposed reaction mechanism provides novel insights into the selective oxidation of alcohols to aldehydes under mild conditions and paves the way for the development of a series of non‐noble metal electrocatalysts.
Sub-GHz breathing dynamics of magnetic hopfions
Cold spells and mortality among people with disabilities: effect modification by cold spell duration, disability type, and severity in Korea
Abstract We aimed to evaluate the mortality risk associated with duration of exposure to cold spells in people with disabilities (PWDs) by disability type and severity. Mortality data for PWDs and non-disabled individuals (NDs) were sourced from the Korean National Health Insurance Service and Ministry of Data and Statistics, respectively, between October and April from 2002 to 2021. Cold spells were defined as a decrease of ≥ 15℃ compared to the previous day with a daily minimum temperature ≤ 3℃ or a daily minimum temperature ≤ − 15℃ by the Korea Meteorological Administration. Mortality risks were estimated using a case time series with a distributed lag non-linear model. Individuals with severe disabilities had a significantly higher risk of accidental mortality during ≥ 2 days of cold spells than on non-extreme cold days (relative risk [95% confidence interval]: 1.726 [1.034, 2.880]). Those with speech, intellectual, mental, and respiratory disabilities had an increased all-cause mortality risk during prolonged events. Specific risks emerged on the first day: visual disabilities (accidental and cardiovascular cause); mental disabilities (cardiovascular cause); hearing disabilities (respiratory cause). Prolonged events are associated with increased mortality risks among severe PWDs, with variations by disability type and severity. Tailored interventions and policies are essential to protect these vulnerable populations during extreme cold.
Synergistic Dynamic Hydrogen‐Bond Engineering in COF Cathode and Hydrogel Electrolyte for Durable NH <sub>4</sub> <sup>+</sup> Storage
ABSTRACT Aqueous ammonium‐ion batteries (AAIBs) have garnered considerable attention for sustainable energy storage, leveraging the rapid diffusion kinetics of NH 4 + ions enabled by Grotthuss‐type proton transport through reversible hydrogen‐bonding interactions. Nevertheless, their practical deployment is often constrained by irreversible side reactions and structural degradation from conventional liquid electrolytes and inorganic cathodes. Herein, we report a dual‐zone design strategy of integrating a tailored hydrogel electrolyte with a redox‐active covalent organic framework (COF) cathode to promote durable NH 4 + storage in AAIBs. In the electrolyte, a pH‐modulated polyacrylamide‐based hydrogel electrolyte with a uniform 3D network suppresses anion‐induced salting‐out effects and facilitates dynamic hydrogen‐bond‐enabled NH 4 + migration. Complementarily, a hexaazatrinaphthalene (HATN)‐based COF (HATN‐COF) cathode with abundant C═O/C═N groups provides multiple reversible hydrogen‐bonding sites for stable NH 4 + storage. As expected, the assembled cell achieves a high initial capacity of 420 mAh g −1 at 0.05 A g −1 and retains a high reversible capacity of 126 mAh g −1 at 2 A g −1 with 70.8% capacity retention after 1300 cycles. This work demonstrates that the dual‐zone design strategy holds great potential for advancing high‐performance AAIBs.