Xiao Xu

Abstract Differences in immunity between males and females in living organisms are generally thought to be due to sex hormones and sex

As a vital cradle of Chinese civilization, the Yangtze River Basin possesses a wealth of ancient architectural heritage that serves as a material record of civilizational evolution. This study takes 688 nationally protected ancient architectural sites within the 11 provincial-level administrative regions along the main stream of the Yangtze River as its research objects. Utilizing GIS platforms and methods including the Nearest Neighbor Index, Kernel Density Estimation, Standard Deviational Ellipse, and Imbalance Index, we systematically analyze their spatio-temporal distribution characteristics. The results indicate the following: (1) Spatially, the ancient architecture exhibits a pattern of “multi-center agglomeration and axial diffusion,” with an overall clustered distribution, forming a dual-core structure with the Jiangsu–Anhui region in the lower reaches as the primary core and the Sichuan Basin in the upper reaches as the secondary core. (2) A quantitative temporal profile of the extant heritage was established, revealing a pronounced pyramid-shaped structure dominated by Ming–Qing (74.56%) and Song-Yuan (18.60%) remnants. Beyond merely reflecting material durability, this profile is shown to be a legacy of historical construction peaks driven by technological standardization and macro-economic shifts, which fundamentally preconditioned the spatial patterns analyzed. (3) The spatio-temporal evolutionary trajectory follows a path from “marginal aggregation” during the Sui, Tang, and Five Dynasties, to the establishment of a “dual-core structure” in the Song–Yuan periods, and finally to “axial diffusion” in the Ming–Qing periods. This study constructs a geographic analysis framework for cultural heritage at the basin scale, and its findings can inform the planning of heritage corridors and provide a reference for regional conservation strategies.

AUTHOR(S): Hua Fan, Liu Xiao Xu, Xiaodong Zhuang ABSTRACT

At present, few studies focus on variable-pitch fans for small-to-medium turbofan engines, with most relying on hydraulic actuation that fails to meet strict environmental and efficiency demands. This paper analyzes an electrically actuated lead-screw servo-motor-driven variable-pitch fan rotor: at 1×10⁷ N/m support stiffness, the first critical speed exceeds the operational range and pitch angle's influence is negligible, peak unbalance response is 1.22×10⁻⁶ m linearly decreasing with pitch angle, and vibration analysis avoids resonance. Results confirm the electric pitch-change concept's feasibility.

Toll-like receptor 7 (TLR7) and Stimulator of Interferon Genes (STING) ligands possess a series of immunomodulatory effects such as anti-infection, anti-tumor, and autoimmune-disease-alleviating effects.

Magnesium hydride (MgH2) is a promising solid-state hydrogen storage material owing to its high hydrogen capacity and low cost, yet its practical application is limited by sluggish kinetics, high operating temperatures, and poor cycling stability. Among various catalytic approaches, Fe-based catalysts have emerged as attractive candidates due to their abundance, compositional tunability, and effective promotion of hydrogen sorption reactions in MgH2 systems. This review critically summarizes recent progress in Fe-based catalysts for MgH2 hydrogen storage, encompassing elemental Fe, iron oxides, Fe-based alloys, and advanced composite catalysts with nanostructured and multicomponent architectures. Mechanistic insights into catalytic enhancement are discussed, with particular emphasis on interfacial electron transfer, catalytic phase evolution, hydrogen diffusion pathways, and synergistic effects between Fe-containing species and MgH2, supported by experimental and theoretical studies. In addition to catalytic activity, key stability challenges—including catalyst agglomeration, phase segregation, interfacial degradation, and performance decay during cycling—are analyzed in relation to structural evolution and kinetic–thermodynamic trade-offs. Finally, a roadmap for the scalable design of Fe-based catalysts is proposed, highlighting rational catalyst selection, interface engineering, and compatibility with large-scale synthesis. This review aims to bridge fundamental mechanisms with practical design considerations for developing durable and high-performance MgH2-based hydrogen storage materials.

Background The hepatocellular carcinoma (HCC) immune microenvironment is heavily influenced by immunosuppressive neutrophils, yet the mechanisms driving their senescence-associated reprogramming remain elusive.Objectives To elucidate the role of Selenoprotein P (Sepp1)-mediated selenium metabolism in driving the accumulation and immunosuppressive function of senescent-like neutrophils in HCC, and its impact on tumour immune evasion.Design We performed integrative single-cell RNA sequencing analyses in HCC mouse models, coupled with functional, metabolic and epigenetic assays to characterise neutrophil subpopulations and dissect the regulatory pathways linking Sepp1 and selenium metabolism to neutrophil senescence-associated reprogramming and tumour progression.Results We identified a distinct subpopulation of senescent-like tumour-infiltrating neutrophils marked by hepatic depletion of Sepp1, elevated Cdkn1a, S100a8/9 and Vegfa. Loss of tumour-derived Sepp1 impaired selenium uptake via Lrp8-mediated transport, suppressing intracellular selenium metabolism and hydrogen selenide production. This led to S-adenosylmethionine accumulation and increased histone H3 protein of trimethylation of lysine 4 histone modification, driving a prosenescence chromatin landscape. Selenium supplementation reversed these effects, restoring Sepp1 expression, reducing neutrophil senescence-associated reprogramming and reinvigorating anti-tumour immunity. Moreover, selenium synergised with anti-programmed cell death 1 therapy to suppress tumour growth.Conclusions Sepp1 is a key regulator of neutrophil senescence-associated reprogramming and immune suppression in HCC through selenium-dependent epigenetic remodelling. Targeting senescent-like neutrophils via selenium supplementation holds therapeutic promise to enhance immunotherapy efficacy in liver cancer.Data are available in a public, open access repository. Data are available upon reasonable request. The raw CUT&RUN sequencing data generated in this study have been deposited in the Genome Sequence Archive (GSA) under accession number CRA032287. The single-cell RNA sequencing data generated in this study have been deposited in the Gene Expression Omnibus (GEO) database under accession number GSE317333. Processed data, analysis scripts and additional sequencing datasets generated and/or analysed during the current study are available from the corresponding author upon reasonable request.

The etiological landscape of hepatocellular carcinoma is shifting markedly, with metabolism-associated fatty liver disease (MAFLD) increasingly being regarded as a major pathogenic factor. The pathophysiological relationship between MAFLD and hepatocellular carcinoma (HCC) involves metabolic disorders, such as impa

Xiao Xu Hongjun Qu Junxing Zhao Shuaijie Peng First published: 17 July 2026 Handling Editor : Dameng Liu

First published: 03 July 2026 Yule Ma, Huigang Li and Huan Chen contributed equally to this work. Handling Editor: Geoffrey Dusheiko