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Chromatin dynamics of the Klf4 locus in mouse pluripotent cells
Abstract Understanding the factors involved in chromatin dynamics is crucial for the study of biochemical processes in which distant genomic regions need to come in close proximity. Previous single locus tracking studies suggest that chromatin dynamics are linked to active transcription, but studies which compare the chromatin dynamics between different locations within a defined chromatin domain are still very limited. Here we used the ANCHOR3 DNA labeling system to track multiple cis -regulatory elements and non-regulatory control regions at different positions in the mouse Klf4 locus. We observe homogeneous chromatin motion of cis -regulatory elements and non-regulatory control regions in Klf4 transcribing mESCs and their non-transcribing EpiLCs daughter cells. These observations challenge the notion that active transcription has a major effect on the locus dynamics of mammalian genes.
Capturing O <sub>2</sub> <sup>•‒</sup> Intermediate to Promote Oxygen‐Reduction‐Reaction Pathway for Li‐O <sub>2</sub> Batteries with High‐Areal‐Capacity
ABSTRACT Oxygen reduction reaction (ORR) with two‐electron transfer pathway is the key reaction for aprotic lithium‐oxygen (Li‐O 2 ) batteries with high theoretical energy density. Herein, we present that capturing ORR superoxide (O 2 •‒ ) intermediate can promote ORR rate and stability by using pyrrolidinium bis(trifluoromethanesulfonyl)imide (Py‐TFSI). Py + cation can bind O 2 •‒ absorbed on the surface of solid catalyst and transfer it into electrolyte, in which the coordination chemistry not only inhibits the generation and disproportionation of LiO 2 on the electrode surface to enhance ORR rate, but also stabilize O 2 •‒ to inhibit its related side reactions for better ORR stability. Over fivefold enhancement of ORR activity is observed. Moreover, Py‐TFSI promotes the uniform lithium deposition through enriching inorganics in solid‐electrolyte‐interphase and electrostatic shielding effect on Li metal surface, resulting in 2.5 times increase of cycling stability of Li electrode. As a result, the Li‐O 2 batteries demonstrate a cycle lifespan of 47 days with a high areal capacity of 5 mAh cm ‒2 . This study presents the deep understanding of intermediate manipulation mechanism for ORR and provides the effective way to improve the performance of metal‐O 2 batteries.
Tetraaza[7]–[15]helicenes Synthesized by Two‐Step Strategy: Length‐Controlled Chiral π‐Systems Exhibiting Amplified Circularly Polarized Luminescence
Abstract Helicenes are chiral π‐conjugated molecules whose properties strongly depend on their lengths. Systematic studies of these compounds have been limited by synthetic challenges. Here we report a concise two‐step strategy (defined as the helicene‐forming sequence from aminohelicene precursors) to access a homologous series of tetraaza[7]–[15]helicenes. Optical spectra converge beyond [11]H, defining a conjugation ceiling, while chiroptical responses amplify sharply, yielding | g lum | up to 0.028. Fluorescence quantum yields show a nonmonotonic dependence, with [7]H and [15]H maintaining both high Φ F (0.39 and 0.36) and large | g lum |, resulting in outstanding, albeit semi‐quantitative, CPL performance, with figures of merit reaching 0.010 and CPL brightness values of approximately 490. TD‐DFT calculations attribute this amplification to the delayed alignment of electric and magnetic transition dipoles, while 1 H NMR shifts of inner protons provide an independent probe of structural reorganization within the helical cavity. Additionally, experiment and theory have consistently identified [11]H as the critical helicene length at which the framework undergoes a qualitative transition. Notably, the [15]helicene constitutes the longest helicene ever resolved into its enantiomers, underscoring the synthetic power of this modular approach. Importantly, our synthetic route is effective for constructing higher‐order helicenes, offering a generalizable platform for length‐controlled, heteroatom‐containing helicenes. These findings establish long tetraazahelicenes as a rare platform where through‐bond conjugation and through‐space orbital coupling act cooperatively to govern photophysical and chiroptical properties.
Investigating the impacts of urban agglomeration spatial structures on carbon emissions based on spatial networks of cities
Active Shell Engineering for Efficient Cascade Triplet Energy Transfer in Lanthanide Heterostructures
ABSTRACT Lanthanide‐doped nanoparticles (LnNPs) exhibit unique optical properties but suffer from severe surface quenching and weak absorption that fundamentally limit their performance. Here, we demonstrate a breakthrough cascade triplet energy transfer (TET) mechanism in precisely engineered NaYbF 4 @Ca 0.8 F 2 :Nd 0.2 @9‐anthracenecarboxylic acid (ACA) heterostructures. This core/active shell/organic molecule configuration combines both molecular sensitization with surface passivation, transforming conventional inert barriers into functional energy conduits. We explore in detail the synthetic conditions required to grow not just optimally active shells but also how best to assemble the organic ligands on the surface of core‐shell LnNPs. Systematic shell thickness optimization (0.8–4.6 nm) reveals an optimal shell thickness of ∼2.0 nm. When coupled with an appropriate ligand exchange strategy, we achieve a remarkable 1200‐fold emission enhancement compared to bare cores. Comprehensive spectroscopic investigations confirm near‐unity TET efficiency and reveal the cascade TET mechanism utilizing Nd 3+ ions as energy intermediates to maximize the Yb 3+ emission. Thus, our mechanism and heterostructure design present one of the most promising synthetic strategies to overcome the existing limitations of traditional LnNPs, establishing new paradigms for high‐performance heterostructures with broad applications in bioimaging, photon conversion, and optoelectronic devices.
Spatiotemporal changes and degradation early-warning of key ecosystem services in China from 2015 to 2020
Abstract Change assessment and degradation early-warning of Key Ecosystem Services (KES) provide a vital scientific foundation for addressing ecological degradation challenges and optimizing ecological governance policies. Counties are the fundamental unit for spatial governance and ecological policy implementation in China. However, the spatiotemporal dynamics and degradation risks of KES at this scale have not been systematically assessed in the context of ecological civilization construction. Focusing on the critical stage of China’s ecological civilization construction from 2015 to 2020, this study took all counties nationwide as the basic units to systematically analyze the spatiotemporal dynamics of three KES: water conservation (WC), soil conservation (SC), and windbreak and sand fixation (WSF). Furthermore, a fact-based ecological degradation early-warning model was developed to enable the precise identification of degraded areas and their respective warning levels. The results showed that: (1) From 2015 to 2020, the three KES nationwide exhibited a trend of overall stability coupled with a slight increase. Spatially, high-value zones for WC were primarily concentrated in the Qinghai-Tibet Plateau (QTP), southern mountainous regions, and key forest zones of Northeast China. High-value zones for SC were predominantly distributed across the Loess Plateau, QTP, Yunnan-Guizhou Plateau, and southeastern hilly and mountainous regions. WSF, in contrast, were highly concentrated in the arid and semi-arid regions of Northern China and the QTP. (2) The ecological degradation early-warning results indicate that 48.96% of counties nationwide were in a “no alert” state, while the remaining counties exhibited varying degrees of functional degradation. Among these, counties under light, moderate, and severe alerts accounted for 36.97%, 12.26%, and 1.83%, respectively. Severe-alert areas were mainly distributed in the extremely arid regions of Northwest China and the karst mountains of Southwest China, largely driven by the substantial degradation of SC functions. Based on these alert types and priority regions, this study proposes tiered ecological governance policy recommendations. Our proposed early-warning framework facilitates the intuitive and efficient identification of county-level KES degradation risks. Thus, the findings offer a scientific foundation for formulating targeted strategies for ecological conservation and restoration in territorial spatial planning.
A Self‐Assembled Single‐Ion Membrane via In Situ Neutralization Enables Triple Stability in Ultrahigh‐Nickel Cathodes
ABSTRACT Ultrahigh‐nickel layered oxides (Ni ≥ 90%) offer exceptional specific capacity but suffer from severe air sensitivity, poor thermal stability, and rapid capacity decay. To date, it is still a significant challenge to address all three bottlenecks simultaneously with a single and integrated strategy, which have severely hindered the large‐scale commercial deployment of ultrahigh‐nickel layered oxide cathodes. Herein, a novel self‐assembling single‐ion conductor membrane, featuring exceptional hydrophobicity, outstanding thermal stability (>445°C), and strong Donnan exclusion against PF 6 − anions, is rationally engineered to holistically enhance the air stability, heat resistance, and electrochemical performance of ultrahigh‐nickel layered oxide cathodes. The N‐cyano‐sulfonamide group on membrane undergoes an in‐situ neutralization reaction with residual LiOH/Li 2 CO 3 on the LiNi 0.9 Co 0.05 Mn 0.05 O 2 (NCM9055), which drives it migration toward the cathode surface and form a self‐assembled protective coating with pronounced hydrophobicity and strong Donnan exclusion. As a result, 3.5 Ah NCM9055/Gr pouch battery demonstrates a commendable capacity retention of 94.97% after 500 cycles. meanwhile the onset temperature of thermal runaway was significantly elevated from 124.2°C to 158.2°C. This work establishes a unified interfacial engineering paradigm that simultaneously addresses the long‐standing triad of bottlenecks plaguing ultrahigh‐nickel layered oxide cathodes, offering a scalable and industrially viable pathway toward safe, long‐life, high‐energy‐density lithium‐ion batteries (LIBs).
Elimusertib enhances cytotoxic effects of conventional chemotherapy and sensitizes to radiation in preclinical Ewing sarcoma models
Abstract Ewing Sarcoma (EwS) is a highly aggressive malignancy predominantly affecting young individuals, with poor prognosis in metastatic or relapsed cases. This study investigates the therapeutic potential of ataxia telangiectasia and Rad3-related protein (ATR) inhibition using the selective small-molecule inhibitor elimusertib, both as a monotherapy and in combination with cytotoxic drugs or radiotherapy. Elimusertib significantly inhibited cell proliferation and induced apoptosis in EwS cell lines. In a chorioallantoic membrane (CAM) model, elimusertib suppressed tumor initiation and reduced tumor volume. Notably, elimusertib exhibited synergistic effects with standard chemotherapeutics and radiation, enhancing antitumor efficacy. These preclinical findings suggest that ATR inhibition by elimusertib may enhance current EwS therapies and enable dose reduction of cytotoxic drugs. Further clinical evaluation is warranted to validate these findings and explore elimusertib’s translational potential in EwS treatment.
A Low‐Permeability TEMPO‐Phosphate as an Anionic Posolyte for Aqueous Redox‐Flow Batteries
ABSTRACT TEMPO is an attractive aqueous redox‐flow battery material but requires the installation of dedicated ionic groups to improve solubility and prevent crossover through ion‐exchange membranes. Although many cationic solubilizing groups have been reported, the library of anionic groups is limited. Here, we report a simple but novel dianionic phosphate solubilizing group for TEMPO. Owing to its −2 charge, the phosphate group leads to much lower TEMPO permeability through a cation exchange membrane than the more common −1 sulfate group. The new TEMPO‐bearing phosphate is paired with a viologen‐based negolyte to assemble a redox‐flow battery, where it achieves a power density of 110 mW cm −2 and a volumetric capacity of 10.6 Ah l −1 . The phosphate group can be extended to other redox‐active motifs and, therefore, represents a straightforward and effective strategy for the design of water‐soluble materials with low crossover.
Ramulus Mori (Sangzhi) alkaloids attenuate diet-induced obesity by modulating adipose tissue metabolic programs
Microstructure-guided design of biopolymer-supported tri-phasic TiO2 for sustainable lead and cadmium detoxification
Abstract The feasibility of synthesizing tri-phasic TiO 2 Nano-particles via the sol-gel method and their immobilization within chitosan biopolymer matrix was investigated. Structural characterization using XRD, HR-TEM, FTIR, and UV-vis DRS confirmed the successful formation of a stable hetero-structure consisting of anatase, rutile, and brookite phases (A 34.6 R 56.8 B 8.6 ) with strong interfacial interactions within the biopolymer matrix. Reduced direct and indirect band gaps to 2.97 and 2.58 eV, respectively, demonstrated improved optical characteristics under sunlight. The immobilized tri-phasic TiO 2 Nano-particles within chitosan biopolymer matrix exhibited significantly enhanced sorption performance toward Pb 2+ and Cd 2+ ions, reaching maximum removal efficiencies of 99.86% for Pb 2+ and 97.85% for Cd 2+ at pH 7, with equilibrium contact times of 90 and 120 min, respectively. According to the Langmuir isotherm model, the maximum removal capacities were 73.67 mg/g for Pb 2+ and 68.72 mg/g for Cd 2+ . These results highlight the potential of the biopolymer-supported tri-phasic TiO 2 Nano-composite as a sustainable and effective material for detoxifying heavy metals in water treatment applications.
Efficient Electrochemical Urea Synthesis From CO <sub>2</sub> and N <sub>2</sub> in Moderate Pressure
ABSTRACT Although electrochemical nitrogen fixation emerges as a sustainable pathway to revolutionize the nitrogen cycle using renewable electricity, the overwhelming dominance of the hydrogen evolution reaction over N 2 activation in aqueous systems imposes fundamental limitations on simultaneously achieving high production rates and Faradaic efficiency. Inspired by Le Chatelier's principle, in this work, an appropriate pressure field was innovatively coupled with electrochemical reduction into the N 2 ‐CO 2 co‐fed urea synthesis system, achieving concurrently suppression of gaseous byproducts of CO/H 2 and enhancement of C–N coupling. Atomically dispersed amorphous Bi x Ni 1‐ x O y clusters were engineered as tandem catalyst, the pressure‐driven in situ electronic modulation of the liquid‐immersed catalyst—originating from increased surface coverage—is for the first time confirmed: Bi sites exhibit a progressive increase in oxidation state, while Ni centers undergo gradual reduction. The rational atomic‐scale integration of multimetallic active centers and system engineering principles for interfacial microenvironment modulation via moderate pressurization achieved breakthrough performance with a high urea production rate of 8.71 mmol h −1 g −1 cat , coupled with remarkable 50% nitrogen fixation efficiency, pointing to one of the best catalysts in aqueous systems among those reported so far. By integrating pressure engineering with atomic‐scale catalyst design, this work provides a guiding paradigm for gas‐involved electrochemical reactions.
RETRACTED ARTICLE: Spin polarized first principles study of electro-magnetic and optical properties of K2NaXI6 (X :Cr Fe) double halide perovskites
Creating Concentration‐Insensitive TADF Luminogens With Spiro‐Fused Xanthone Acceptors for Highly Efficient OLEDs
ABSTRACT Robust thermally activated delayed fluorescence (TADF) materials have shown promising applications as emitters and sensitizers for next‐generation organic light‐emitting diodes (OLEDs). However, most TADF materials have to be dispersed in host matrices at precisely low concentrations to prevent serious emission quenching and exciton annihilation, which is unfavorable in the OLED industry. Herein, four tailored TADF luminogens built with spiro‐fused xanthone acceptors and acridine‐based spiro donors are developed. Thanks to the rigid and bulky donor and acceptors, these new TADF luminogens hold fast reverse intersystem crossing process and emit strong cyan to green light with high quantum yields of up to 91% and 99% in neat and doped films, respectively. They have balanced bipolar charge transport ability and prefer horizontal dipole orientation. The non‐doped OLEDs using them as emitters show an excellent external quantum efficiency (EQE) of 30.6%, with ultra‐small roll‐offs. They enjoy concentration insensitivity in doped OLEDs, and the EQEs stay stable (29.1%‒36.8%) in various concentrations (10‒90 wt%) with very small roll‐offs. Finally, they can serve as efficient sensitizers for multi‐resonance emitters in narrow‐spectrum OLEDs, providing impressive EQEs of 41.0% with suppressed roll‐offs. This work reveals an applicable molecular design strategy of TADF materials for high‐performance OLEDs.
Genetic diversity of indigenous carambola (Averrhoa carambola L.) accessions based on fruit morphometric and biochemical traits
An Amorphous Nanocomposite for Dual‐Mode Metabolic Fingerprinting and Diagnosis of Adolescent Depressive Disorder
ABSTRACT Adolescent depressive disorder (ADD) is a chronic and debilitating mental disorder, yet its diagnosis still relies on subjective assessment. An efficient and cost‐effective diagnostic tool for ADD is urgently needed to improve clinical management. Herein, amorphous MIL‐88B@nitrogen/sulfur co‐doped carbon‐dots ( a MIL‐88B@NSCDs) are designed as a dual‐ion mode matrix for comprehensive metabolic profiling of ADD. The a MIL‐88B@NSCDs with integrated physicochemical properties facilitate the efficient dual‐ionization of metabolites, enabling the selective ionization of metabolites from bio‐samples. It exhibits a 5–12‐fold signal enhancement over NSCDs (a well‐established dual‐ion mode matrix) and shows high reproducibility with coefficients of variation ≤ 10%. Next, we directly extracted the dual‐ion mode serum metabolic fingerprints (dual‐SMFs) with 432 features (defined as signal‐to‐noise ratio (S/N) > 3, 190/242 in positive/negative ion mode) within seconds. Based on the dual‐SMFs, we constructed a high‐performance diagnostic model for ADD, with an area under the curve (AUC) of 0.926 (0.760/0.734 in positive/negative ion mode). This work not only contributes to the development of the dual‐ion mode matrices but also provides an efficient and comprehensive strategy for the precision clinical management of ADD.
Berberine-entrapped albumin nanoparticles ameliorate chemically induced liver injury by restoring oxidative balance and autophagic-apoptotic crosstalk
Abstract This study investigated the therapeutic potential of berberine-entrapped bovine serum albumin nanoparticles (BRB-BSA NPs) in alleviating chemically induced liver injury in rats. Molecular docking was first performed to examine BRB interactions with phosphoinositide 3-kinase (PI3K), a key regulator of cellular survival and autophagy pathways. Hepatotoxicity was induced using diethylnitrosamine (DEN) and carbon tetrachloride (CCl₄), resulting in significantly elevated serum uric acid levels (1.35 ± 0.1 mg/dL), oxidative imbalance, disrupted autophagic signaling, and histological liver damage. Post-injury treatment with BRB-BSA NPs significantly reduced serum uric acid (0.20 ± 0.07 mg/dL, p < 0.05 vs. DEN/CCl 4 ), surpassing the prophylactic regimen and restoring levels comparable to healthy controls. Oxidative status improved, with increased superoxide dismutase (SOD) activity and reduced nitric oxide (NO) and xanthine oxidase (XO) levels. Autophagic signaling was normalized through downregulation of PI3K, mTOR, and p62, alongside upregulation of LC3, indicating restoration of autophagic flux. Apoptotic balance shifted toward pro-apoptotic signaling, with elevated Bax and reduced Bcl-2 expression, supporting the therapeutic potential that BRB-BSA NPs may exert. Histological assessment confirmed near-complete hepatic architecture recovery in the treatment group, while the prophylactic group exhibited partial protection. Collectively, these findings highlight the potent therapeutic role of BRB-BSA NPs in reversing DEN/CCl 4− induced hepatic damage by restoring metabolic, oxidative, autophagic, and apoptotic homeostasis, underscoring their promise as a nanoformulated hepatoprotective intervention.
Hierarchical Solvation Chemistry via Ether–Ester–Cosolvent Synergy Enables High‐Performance Lithium‐Metal Batteries at a Low Temperature
ABSTRACT Lithium metal batteries (LMBs) offer high energy densities but are frequently plagued by rapid degradation under extreme conditions, such as low temperatures or high C‐rates. This performance decay stems primarily from sluggish Li + transport kinetics and high desolvation energy penalties imposed by conventional electrolytes. Herein, we engineer a hierarchically solvating electrolyte system comprising a weakly coordinating ether (tetrahydropyran, THP), a strongly coordinating ester (methyl propionate, MP), and lithium difluoro(oxalato)borate (LiDFOB). This molecular configuration fosters an anion‐enriched primary solvation sheath, effectively minimizing the activation energy required for Li + desolvation. Furthermore, the incorporation of trifluorotoluene (TFT) as a non‐solvating diluent modulates the local solvation structure toward aggregate dominance, thereby promoting the formation of a compact and homogeneous solid electrolyte interphase (SEI). Through precise compositional tuning, we achieve a robust SEI architecture characterized by the uniform distribution of ductile organic matrices and high‐modulus inorganic species. This mosaic structure provides an optimal mechanical balance of rigidity and elasticity, preserving interfacial integrity during prolonged cycling at cryogenic temperatures. Consequently, Li||Li symmetric cells exhibit ultrastable cycling for over 6000 h at −25°C. In Li||LiCoO 2 full cells, the electrolyte supports 400 stable cycles, retaining 85.5% and 66.2% of the nominal room‐temperature capacity at −25°C and −45°C, respectively. These findings offer critical design principles for tailoring solvation chemistry to enable high‐performance LMBs in extreme environments.