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The Hubbard U for a metal-oxo unit depends on how electrons are screened in its host material. This screening is governed by (i) local screening determined by coordination, oxidation state, and metal-ligand hybridization and (ii) the longer-range dielectric response of the surrounding lattice. Consequently, the common practice of directly transferring U from extended metal oxides to metal-organic frameworks (MOFs) with the same metal-oxo unit risks systematic errors. Here, we take UiO-66(Ce) as a prototypical MOF and determine the node-specific linear-response Hubbard parameter U (ULR) for four commonly employed GGA functionals used to describe the Ce 4f orbitals of the Ce6O8 node. We then benchmark GGA + ULR against experiment and HSE06 for both pristine and the node-reduced UiO-66(Ce). GGA + ULR reproduces the structural and electronic properties, whereas using the U value transferred from CeO2 leads to a deviated description of the redox activity. However, transferring node-specific ULR between MOFs that share the same node and comparable screening environments is physically justified and practically useful for GGA + U calculations of large-cell MOFs. This conditional transferability is validated by applying the ULR derived from UiO-66(Ce) to NU-1000(Ce), successfully reproducing hybrid-functional results across seven proton topologies. The larger ULR obtained for the Ce6O8 node compared to that for CeO2 reflects more ionic Ce-O bonding and distinct redox chemistry of the MOF node. Such deviations are not limited to the present case but are anticipated for metal-oxo units in MOFs more broadly, enabling node chemistries that are different from those of the extended phase.

Flexible transition metal nitrides (TMNs) are considered key candidate materials for constructing next-generation high-performance flexible sensing devices. However, their strong metal-nitrogen bonds require high-temperature synthesis, which tends to cause spontaneous aggregation into three-dimensional bulk materials, making it difficult to obtain ultrathin two-dimensional materials suitable for flexible devices. This study proposes an innovative rapid and nondestructive microwave crystallization method. By ingeniously leveraging the abundant free electrons in quasi-metallic TMN nanostructures, electromagnetic irradiation induces efficient microwave heating, achieving exceptional crystallization within 20 s. This method effectively circumvents the sintering of ultrathin nanostructures inherent to conventional high-temperature annealing and increases the specific surface area of the product by more than 10-fold. Based on this method, dense and robust flexible TMN films with ultrahigh specific surface area and excellent chemical stability have been successfully obtained, enabling highly sensitive surface-enhanced Raman spectroscopy (SERS) detection of polycyclic aromatic hydrocarbons and nanoplastics.

Antibiotic cocontamination poses a severe but poorly understood threat to crop photosynthesis. This study employed an integrated multiscale framework to uncover the phytotoxicity of tetracycline (TC) and ciprofloxacin (CIP) on rice seedlings and evaluate the mitigation potential of nanobiochar (nBC). Coexposure to TC and CIP amplified antibiotic residues in both root and shoot, exacerbating growth inhibition and photosynthetic pigment depletion, with the net photosynthetic rate plummeting to 1.44 μmol CO2 m-2 s-1. Mechanically, chlorophyll fluorescence and transmission electron microscopy revealed complementary photoinhibition pathways: TC impaired the donor side of photosystem II, whereas CIP blocked the acceptor side, jointly disrupting the electron flow and causing extensive thylakoid disintegration. Critically, nBC amendment effectively reduced tissue antibiotic burden, restored photosynthetic function (light-saturated rate recovered to 3.94 μmol CO2 m-2 s-1), and attenuated metabolomic disturbance, decreasing differential metabolites from 981 to 858. These coordinated recoveries demonstrate that nBC mitigates toxicity primarily by reducing antibiotic bioavailability. This work establishes a novel diagnostic framework linking physiological impairment to subcellular damage and metabolic reprogramming, providing a mechanistic basis for using nBC to safeguard crop productivity against antibiotic mixtures in agroecosystems.

High fructose intake has been linked to metabolic and cognitive disturbances, yet its effects on hippocampal synaptic architecture remain unclear. We examined whether four weeks of fructose feeding alter metabolic parameters or CA1 synaptic ultrastructure in adult rats maintained on isocaloric AIN-93G diets containing fructose, glucose, or starch as the primary carbohydrate source. Serum biochemical and hormonal profiles showed only modest, diet-specific differences without major metabolic disruption. Quantitative electron microscopy revealed similar dendritic spine density, postsynaptic density length, perforated synapse frequency, and multisynaptic bouton density across groups, whereas fructose-fed rats displayed a small but significant reduction in spine area and an alteration in circularity. These localized geometric changes occurred without broader synaptic remodeling. Overall, our findings indicate that short-term fructose exposure under metabolically controlled, solid-diet conditions produces minimal metabolic and ultrastructural effects, in contrast to the pronounced disturbances reported in metabolically stressful paradigms, suggesting that structural consequences of fructose depend strongly on dietary context and metabolic load.

Icariside II is an active compound extracted from Herba EpimedII, a traditional Chinese medicine known for its remarkable effects in treating erectile dysfunction and arthritis. However, the specific mechanism underlying its anticancer activity in bladder cancer remains unclear. This study aims to explore the effects and mechanisms of Icariside II in bladder cancer. We validated the role of Icariside II in bladder cancer through various in vitro experiments. Additionally, transcriptome sequencing was performed to explore the potential mechanism of Icariside II in suppressing bladder cancer. The results of the transcriptome sequencing were further confirmed by Western Blot, immunofluorescence, and Transmission Electron Microscope. In vivo validation was conducted using tumor xenograft models. Our findings demonstrated that Icariside II effectively inhibited the proliferation and migration of bladder cancer. Transcriptome sequencing revealed significant alterations in autophagy and Endoplasmic Reticulum stress related genes in bladder cancer cells after treatment with Icariside II. This result was supported by the observations made through Transmission Electron Microscope and Western Blot. Further investigations indicated that Icariside II induced autophagy through the IRE1α and PERK pathway and inhibited autophagic flow by reducing the number of lysosomes and suppressing their activity. In tumor xenograft models, Icariside II significantly inhibited bladder cancer proliferation. Our data suggest that Icariside II holds promise as a natural medicine for the significant inhibition of bladder cancer, achieved through the induction of endoplasmic reticulum stress-induced autophagy and inhibition of lysosomal activity.

Food allergy is a potentially serious immune system reaction that significantly impacts the quality of life for individuals. Studies have shown that dysregulation of circular RNAs (circRNAs) mediates the activation of immune cells and inflammatory mechanisms in allergic diseases. This study aimed to elucidate its functions and the pathways involved in food allergic reactions. A Th2-polarized food allergy model was established in BALB/c mice using ovalbumin (OVA) adsorbed to aluminum hydroxide. Allergic responses were evaluated using a combination of clinical scoring, histology (H&E), and transmission electron microscopy (TEM). Serum IgE and cytokines (IL-4, IL-5, IL-13) were measured by ELISA. Molecular expressions were analyzed by western blot and qRT-PCR. RNA immunoprecipitation (RIP) and PAR-CLIP assays validated RNA-protein interactions. circS100A11, EIF4A3, and PKD1 was upregulated in sensitized mice. EIF4A3 was found to bind to and stabilized PKD1 mRNA, and its overexpression exacerbated allergic reactions in a PKD1-dependent manner. circS100A11 was found to directly interact with EIF4A3, promoting the recruitment of EIF4A3 to the PKD1 transcript. circS100A11 knockdown alleviated allergy, which was reversed by EIF4A3 overexpression. The detrimental effects of the circS100A11/EIF4A3 axis were abolished by concurrent PKD1 knockdown. Our findings define a novel regulatory pathway in which circS100A11 aggravates food allergy by recruiting EIF4A3 to enhance PKD1 expression, presenting a potential therapeutic target for intervention.

Understanding the behavior of electrocatalysts under operating conditions is essential to improving their performance. Electrochemical (scanning) transmission electron microscopy [EC-(S)TEM] enables real-time, high-resolution imaging of materials undergoing electrochemical processes; however, it provides limited information about the products of these processes in the solution phase, and the high-energy electron beam can perturb their distribution and reactivity through radiolysis. Previously, we demonstrated that Ni2+ not only enhances the electrocatalytic performance of Pt for the hydrogen evolution reaction (HER) but also, through Ni(OH)2 precipitation, that it serves as a quantitative in situ marker of HER activity at the single-nanoparticle level. Extending this quantitative footprinting methodology to EC-(S)TEM to report catalytic yield, we observe a different mechanism: while optical measurements indicate the expected Ni(OH)2 precipitation on the EC-(S)TEM chip, in situ EC-(S)TEM experiments reveal beam-induced reduction of Ni2+ to metallic Ni via radiolysis. Finite element modeling supports a mechanism involving H• intermediates and allows discrimination of the respective contributions of the HER and the electron beam. These results highlight the critical role of the beam in apparent electrocatalytic reactivity and provide a framework to quantify catalytic yields in EC-(S)TEM and to interpret operando data more cautiously.

Two-dimensional hexagonal boron nitride (hBN) is attractive for several emerging applications. Ion bombardment can be used to modify the hBN properties. However, the understanding of radiation damage buildup in hBN remains limited. Here, we investigate the effects of the dose rate and ion mass on radiation damage buildup by studying 40 nm-thick hBN films bombarded at room temperature with 500 keV 4He, 15N, 40Ar, and 129Xe ions and comparing with results for ion bombardment of polycrystalline hBN ceramics. Raman spectroscopy is used to quantify damage buildup, and transmission electron microscopy is used for microstructural analysis. Experiments are complemented by molecular dynamics simulations of the formation and evolution of point defects. Lighter ions are found to be more efficient at disordering hBN than heavier ions. This observation points to a critical role of intracascade defect processes. In contrast, a negligible dose rate effect observed suggests limited intercascade defect dynamic annealing processes for these irradiation conditions. These findings provide a fundamental basis for hBN defect engineering.

Pediatric hepatocellular carcinoma (HCC), a rare and life-threatening malignancy that typically arises de novo, is strongly associated with underlying metabolic or genetic disorders. Its molecular pathogenesis remains poorly understood due to the limited number of well-documented cases. Herein, we present the case of an 11-year, 5-month-old boy who presented with incidentally detected cirrhosis, growth retardation, and severe pruritus. Whole-exome sequencing revealed a novel homozygous variant in the mitochondrial transcription factor A (TFAM) gene (c.197C>A; p.Pro66His) and compound heterozygous variants in the tight junction protein 2 (TJP2) gene (c.142G>C; p.Val48Leu and c.877C>T; p.Arg293Trp), all classified as variants of uncertain significance (VUS). Immunohistochemistry confirmed reduced expression of TFAM and TJP2, while electron microscopy demonstrated abnormal mitochondrial ultrastructure and compromised biliary epithelial integrity, supporting a diagnosis of combined TFAM and TJP2 deficiency. The disease rapidly progressed from moderately to well-differentiated HCC within 15 months. Following laparoscopic tumor resection, the patient successfully underwent orthotopic liver transplantation at 13 years of age, with normal graft function maintained at the 8-month follow-up. This case provides insights for the diagnosis and management of pediatric liver disease involving multiple VUS, suggests a potential novel pathogenic mechanism of HCC, and highlights the possible synergistic effects of multigene variants. Whether combined TFAM and TJP2 deficiencies directly and synergistically accelerate liver disease progression and hepatocarcinogenesis warrants further validation through additional clinical cases and functional studies.

Although lithium-sulfur (Li-S) batteries are promising next-generation energy storage devices, polysulfide shuttling and electrode volume deformation remain challenges for their practical applications. Herein, a groundbreaking modification strategy is proposed that leverages an integrated cathode design to synchronously restrict polysulfide shuttling and enhance electrochemical kinetics. Specifically, the poly(ionic liquid) termed VIBM with high ionic conductivity is in situ intermittently encapsulated on S surface, which effectively facilitates Li+ transport and ensures free electron transfer stemming from sufficient contact between exposed S area and conductive agents. As a result, polysulfides are physically and chemically confined within cathode region, while electrochemical reaction kinetics are enhanced. Moreover, the highly flexible VIBM coating can accommodate electrode volume fluctuations. The resulting Li-S cells demonstrate exceptional cycling durability and rate capability with reduced self-discharge behavior. This innovative cathode encapsulation strategy opens a new path for addressing "shuttle effect", thus promoting the development of Li-S batteries.

Circularly and elliptically polarized high-order harmonics are powerful tools for probing ultrafast dynamics in chiral and magnetic materials. However, previous methods for generating elliptically polarized harmonics impose stringent requirements on the driving laser or the target medium. Here, we present a new method for generating harmonics with tunable ellipticity by driving both atoms and randomly aligned molecules with a two-dimensional two-color field. This field consists of an elliptically polarized fundamental component and a linearly polarized second-harmonic component, which together control the two-dimensional electron motion and hence the intra-cycle interference of harmonic radiation, resulting in elliptically polarized harmonics. Molecular structure effects can further modulate the harmonic polarization, enabling the generation of harmonics with consistently positive or negative helicity across a broad spectral range as well as the synthesis of attosecond pulses with high ellipticity. Our method provides a broadly applicable and flexible approach to generating elliptically polarized high-order harmonics and attosecond pulses.

Prokaryotic Argonaute proteins (pAgos) are nucleic acid-guided endonucleases with diverse functions. Mucilaginibacter paludis Argonaute (MbpAgo) is unusual in using guide DNA (gDNA) to cleave target RNA (tgRNA), but the structural basis for this activity has been unclear. Here we present cryo-electron microscopy structures of MbpAgo in apo, binary, and ternary states at up to 2.55 Å resolution. The apo structure reveals a conserved bilobal scaffold with unique insertions in the PIWI and MID domains that stabilize the catalytic conformation. Upon gDNA binding, MbpAgo forms a dimer stabilized by multiple protein-protein interfaces and an auxiliary nucleic acid-like density bridging the PAZ-MID lobes. The auxiliary nucleic acid interactions coordinate gDNA binding and dimer stabilization to support MbpAgo activity, with dimerization becoming particularly important for efficient cleavage with double-stranded DNA (dsDNA) guides. Binding of tgRNA induces a DNA-RNA hybrid duplex and conformational changes that destabilize the dimer, reverting MbpAgo to an active monomer capable of cleaving structured viral RNAs such as the SARS-CoV-2 5'UTR and HIV-1 CES. These findings suggest a dynamic monomer-dimer transition as both the regulatory mechanism of MbpAgo and an evolutionary adaptation for processing dsDNA-derived guides, providing a structural framework for programmable RNA targeting.

Conventional allele specific PCR (AS-PCR) genotyping using gel electrophoresis and ethidium bromide (EtBr) is costly, particularly in developing countries. It also poses health risks to working personnel as it requires specialized equipment and toxic dyes like ethidium bromide. Hence, the present study developed a simple and cost-effective colorimetric genotyping method using gold nanoparticles solution (AuNPs) and unmodified primers. Specifically, 15μl of AuNPs solution was found sufficient for detecting an amplicon in 5μl of PCR product. In this approach, the amplified PCR products appear red while the non-amplified PCR products appear blue with a PCR mastermix without a dye. Transmission Electron Microscopy (TEM) revealed the sequestration of AuNPs in amplified PCR products and the aggregation of AuNPs in non-amplified PCR products, resulting in red and blue colors, respectively. The method was tested on genotyping of six SNPs from six genes (Akr1c3, Plg, Myf5, Sec14l2, Tpm1, and Lama2) in buffaloes, and the results were perfectly matched with those obtained using agarose gel electrophoresis analysis. Therefore, the AS-PCR combined with AuNPs provides an easy visual detection method for the amplified and non-amplified PCR products of single-nucleotide polymorphisms (SNPs). In addition, the presented method has the potential to replace agarose gel electrophoresis, the use of EtBr, and UV-transilluminator.

Catalyst design is essential for advancing sustainable chemistry, particularly through heterogeneous systems that offer recyclability and environmental benefits. Herein, we report the synthesis and application of a novel covalent triazine framework (CTF) incorporating 1,10-phenanthroline units, which serve as coordination sites for Cu(I) ions. The resulting heterogeneous catalyst, Cu@Phen-CTF, was prepared through postsynthetic metalation and fully characterized by Fourier-transform infrared, Raman, solid-state nuclear magnetic resonance, scanning electron microscopy/energy-dispersive X-ray, transmission electron microscopy, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller surface area analysis, confirming successful Cu(I) incorporation and structural integrity. This catalyst was applied to the tandem cyclization of 2-iodoanilines with isothiocyanates to access pharmacologically relevant 2-aminobenzothiazole derivatives. The Cu@Phen-CTF system showed excellent catalytic activity under mild conditions (50 °C, toluene, 72 h), affording high yields and a broad substrate scope. Furthermore, the material demonstrated good thermal stability, negligible leaching, and high recyclability, maintaining performance across multiple catalytic cycles.

Localized chemotherapy offers a promising strategy to improve therapeutic efficacy while minimizing the systemic toxicity of conventional cancer treatment, particularly following tumor resection. Electrospun nanofibers are well suited for this purpose due to their high porosity, extracellular matrix-mimicking architecture, and capacity for localized drug release. In this study, electrospun nanofibers based on PCL and PLGA were developed for localized cancer therapy. Three distinct nanofibrous architectures were fabricated: PCL nanofibers, PCL-PLGA blended nanofibers, and PCL-PLGA multilayered (tetra-layered) nanofibers, and their encapsulation efficiency was determined by high-performance liquid chromatography (HPLC). Scanning electron microscopy confirmed uniform, bead-free nanofibrous morphologies, while Fourier transform infrared spectroscopy and thermal analyses verified effective polymer blending, molecular interaction, drug incorporation, and enhanced thermal stability. The incorporation of PLGA altered the degradation rate and surface wettability of the nanofibers, enabling modulation of drug release behavior. Biological evaluations demonstrated acceptable hemocompatibility, favorable interactions with RAW 264.7 macrophages, and high cytocompatibility across all formulations. Importantly, nanofiber architecture significantly influenced release profiles (curcumin dye as a model), with multilayered or blend nanofibers exhibiting reduced burst release and prolonged drug delivery compared to single-polymer systems. In addition, proliferation clonogenicity and western blotting assays confirm their corresponding high cytotoxic responses (docetaxel as a model). Overall, this work demonstrates that architectural and compositional engineering of PCL-PLGA electrospun nanofibers provides a robust and adaptable platform for localized, sustained cancer therapy.

Methionine restriction has emerged as a promising strategy for extending lifespan and enhancing cancer therapy. LAT4, an amino acid transporter encoded by SLC43A2, is frequently overexpressed in multiple cancers and critically contributes to systemic methionine accumulation. However, the structural basis of LAT4 function remains poorly understood, and no effective inhibitors have been developed to date. In this study, we present high-resolution cryo-electron microscopy structures of LAT4 and the related SLC43A3-encoded purine transporter ENBT1. The phenylalanine-bound structure of LAT4 enables the characterization of the substrate binding pocket. Comparison of the outward-facing ENBT1 and inward-facing LAT4 structures identifies key residues involved in the methionine transport process. Structural analysis of digitonin binding to the central cavity of LAT4 enabled identification of tubeimoside-1 (TBM-1) as a potent inhibitor of LAT4-mediated methionine uptake. We demonstrate that tubeimoside-1 reduces methionine uptake in B16F10 cancer cells. Furthermore, TBM-1 suppresses tumor progression in the MMTV-PyVT mouse model of breast cancer through systemic methionine restriction. Our study provides insights into the LAT4 transport mechanism and identifies tubeimoside-1 as a potent inhibitor of methionine uptake and establishes a foundation for developing LAT4-targeting therapeutics to restrict methionine uptake.

Industrial production of malic acid remains dependent on fossil resources or, when performed microbiologically, on sugar-based feedstocks. Both routes come with caveats, generating emissions and competing with food supply. The use of CO₂-derived one-carbon substrates offers a promising alternative to circumvent these constraints. In this study, the malic acid production process from methanol in metabolically engineered Ogataea polymorpha NYCY495 LEU-ΔSTE12 Pyc Mdh MAE1 strain was optimised and scaled up. A two-phase cultivation strategy, using glycerol for biomass formation and methanol for product synthesis, was established in shake flasks and subsequently transferred to a 1 L bioreactor. Process optimisation through automated feeding strategies was evaluated. DO-based feeding was the most effective approach, using a combination of methanol and glycerol, achieving a final molar yield of 0.1 molMA molMeOH ⁻¹ and a maximum productivity of 0.5 g L⁻¹ h⁻¹. This successful fermentation strategy was validated using green methanol, showcasing the feasibility of "closing the loop" as envisioned in the bioeconomy. Finally, a comparative study of the effect of glycerol, methanol, and their mixture on O. polymorpha NYCY495 LEU-ΔSTE12 Pyc Mdh MAE1 methanol metabolism, peroxisome biogenesis, and cellular redox balance is presented, supporting the positive cumulative effect of both on gene transcription.

Hydrogen diffusion plays a key role in hydrogen-metal interactions and is closely linked to embrittlement in steels. In iron-based alloys, the influence of local atomic environments on hydrogen diffusion is well recognized, whereas the role of alloy composition remains unclear. Fe-Cr binary alloys, therefore, provide a simple and well-defined model system to isolate the effect of Cr on hydrogen diffusion in iron lattices. In this work, hydrogen diffusion in Fe-Cr alloys is investigated using first-principles calculations based on density functional theory. Ab initio molecular dynamics simulations are further employed to evaluate the influence of Cr concentration on hydrogen diffusion coefficients. The results show that hydrogen diffusion in Fe-Cr alloys is strongly suppressed compared with bcc Fe. This suppression is primarily attributed to higher migration energy barriers resulting from strong Fe-Cr interactions and more compact local atomic packing. Charge transfer analysis demonstrates that hydrogen behaves as an electron acceptor, and the amount of charge transferred is inversely related to the migration barrier. In the disordered solid-solution models, the hydrogen diffusion coefficient decreases with increasing Cr content in the low-Cr range, whereas in the ordered alloy models it exhibits a non-monotonic dependence on composition, with a minimum near 25 at. % Cr. These results reveal the electronic and structural origins of composition-dependent hydrogen diffusion in Fe-Cr alloys at the atomic scale.

Acquiring information on the evolution of chemical states and real-space morphological changes under identical reaction conditions is crucial for elucidating the mechanisms of heterogeneous catalytic reactions. In this study, we design and implement a microreactor with high electron transparency, enabling correlated in situ x-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) measurements for the same type of sample under identical reaction environments, while integrating online mass spectrometry for seamless coupling of spectroscopic and imaging data. This advancement allows direct correlation between the in situ chemical-state information obtained by XPS and the real-space structural evolution captured by TEM. Using the oxidation-reduction process of Ni nanoparticles in O2/H2 atmospheres as a model reaction, we systematically investigate the dynamic relationship between surface chemical states and morphological reconstruction from near-ambient to ambient pressures, demonstrating the stability and applicability of the microreactor under complex gas environments. This work provides a new experimental approach for mechanistic studies of gas-solid interfacial reactions under realistic operating conditions and establishes a methodological foundation for the rational design and optimization of high-performance catalysts.