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关键词： 4O2 catalyst   sub>4Zr31   DRM   Ni   Oxygen vacancy   Photothermal catalysis  

摘要： Dry reforming of methane (DRM) is a pivotal technology in the carbon cycle field. It can co-convert CH₄ and CO₂ into syngas, achieving the resource utilization of greenhouse gases and providing an innovative solution for mitigating the climate crisis. Based on prior research on Ce_1-xZr_xO₂ catalysts, the present study constructs a model featuring Ni clusters supported on the Ce_1/4Zr_3/4O₂(111) surface with the introduction of oxygen vacancies. By integrating density functional theory (DFT) calculations, we explore the enhancement effect of oxygen vacancies and their synergy with photothermal conditions on the DRM reaction mechanism. The results show that oxygen vacancies optimize the charge distribution and serve as key active sites for improving catalytic performance. In the reaction pathway, CH species react through an oxygen-assisted dehydrogenation route, effectively suppressing carbon deposition. By applying an external electric field to simulate the photo-generated carrier effect, it is found that the field can drive the directional migration of electrons from the support to the active metal Ni, generating a synergistic enhancement effect with the electron supply from oxygen vacancies. This synergy significantly optimizes the adsorption configurations and transition state energies of reaction intermediates. The current study reveals, at the atomic scale, the mechanism by which the synergy between oxygen vacancies and photothermal conditions enhances DRM efficiency, providing a basis for designing catalysts.

关键词： Kurdyka-Łojasiewicz property   Linear convergence   Proximal alternating maximization   Robust   Simultaneous tensor/matrix diagonalization  

摘要： This study investigates the ℓ₁-norm simultaneous approximate matrix diagonalization problem, aiming to mitigate the sensitivity of the ℓ₂-norm model to outliers. A proximal alternating maximization algorithm ℓ₁-PAM is developed using polar decomposition. We establish linear convergence based on the Euclidean Kurdyka-Łojasiewicz property and exponent. The algorithm and global convergence results are successfully extended to d-order tensors. Comparative experiments and color face reconstruction demonstrate the superior efficiency and robustness of ℓ₁-PAM against outliers and noises.

关键词： Ba(Mg1/3Ta2/3)O3   CMAS corrosion behavior   Corrosion mechanism   Microstructural evolution   Thermal barrier coatings  

摘要： Calcium–magnesium-alumino-silicate (CMAS, CaO-MgO-Al₂O₃-SiO₂) corrosion poses a critical threat to the durability of thermal barrier coatings (TBCs) in high-temperature turbine environments. In this study, the CMAS corrosion behavior of plasma-sprayed Ba(Mg_1/3Ta_2/3)O₃ (BMT)-YSZ double-ceramic-layer coatings was investigated under varying temperatures and exposure durations. Cross-sectional microstructural characterization and phase analysis, combined with first-principles calculations, elucidate the evolution of reaction products and cation transport during corrosion. Molten CMAS initially infiltrates the porous coating through microcracks and reacts preferentially with highly diffusive Ba, forming Ba-rich reaction products. With increasing temperature and exposure time, CMAS infiltration is enhanced due to improved wettability, while Ta gradually participates in the interfacial reactions. Distinct corrosion features are observed at different stages, the corrosion mechanism correspondingly evolves from grain boundary attack to intragranular corrosion. Throughout the corrosion process, CMAS is progressively consumed via chemical reactions within the BMT layer, which effectively delays its further penetration and preserves the chemical integrity of the underlying YSZ layer under the tested conditions.

关键词： 1,5-Diamino-2-hydroxypentane   3-Hydroxylysine   l-lysine 3-hydroxylase   l   SpLDC   Pathway enhancement  

摘要： 1,5-Diamino-2-hydroxypentane (2-OH-PDA) is a novel aliphatic β-amino alcohol with potential for a wide range of applications, and its efficient and green synthesis has attracted increasing attention. In this study, we developed a biosynthetic pathway for 2-OH-PDA from glucose. Firstly, the Fe²⁺/α-ketoglutarate (α-KG)-dependent l-Lysine-3-hydroxylase (K3H) was heterologously expressed in E coli NT1003 capable of highly producing l-lysine to construct a biosynthetic pathway strain of 3-hydroxylysine (3-OH-lysine). By intensifying the pathway, introducing a glutamate oxidation system, and optimizing the fermentation conditions, 40.2 g/L 3-OH-lysine were achieved in the fed-batch fermentation. Then, lysine decarboxylase (SpLDC) was used to catalyze the decarboxylation of 3-OH-lysine to 2-OH-PDA, yielding 29.2 g/L with a molar conversion efficiency of 99.7%. This study provides an economical, efficient and green route for the biosynthesis of 2-OH-PDA.

关键词： 髓核细胞   腰椎间盘突出症   氧化应激   铁死亡   水凝胶   铁抑素1   生物材料  

摘要： 背景:针对铁死亡的分子机制,干预铁代谢或抑制脂质过氧化有望成为治疗腰椎间盘突出症的新策略,为疾病防治提供新的研究方向。目的:以聚乳酸-羟基乙酸共聚物-聚乙二醇-聚乳酸-羟基乙酸共聚物水凝胶作为载体,通过体外细胞实验和动物体内实验观察铁死亡抑制剂铁抑素1对腰椎间盘突出症的作用机制。方法:(1)将第3代小鼠髓核细胞分3组处理:对照组不进行任何处理,模型组添加10 ng/mL白细胞介素1β,铁抑素1组加入10 ng/mL白细胞介素1β+25μmol/L铁抑素1处理,检测细胞内丙二醛水平、谷胱甘肽水平、铁离子含量以及细胞外基质相关基因Ⅱ型胶原蛋白、聚集蛋白聚糖、基质金属蛋白酶3 mRNA表达。(2)制备负载铁抑素1的聚乳酸-羟基乙酸共聚物-聚乙二醇-聚乳酸-羟基乙酸共聚物水凝胶(载药水凝胶),表征水凝胶的微观形貌与体外药物释放情况。将80只C57BL/6小鼠随机分为正常组、模型组、游离药物组和载药水凝胶组,每组20只。除正常组外,其余3组建立L5/6腰椎间盘突出症模型,模型组、游离药物组和载药水凝胶组椎旁组织分别注射PBS、铁抑素1溶液、载药水凝胶,动态监测各组小鼠机械痛和热痛阈值。给药第7天提取髓核组织,检测炎症因子(肿瘤坏死因子α和白细胞介素1β)、丙二醛、谷胱甘肽水平以及铁死亡通路相关基因谷胱甘肽过氧化物酶4、溶质载体家族7成员11 mRNA表达。结果与结论:(1)与对照组相比,模型组细胞内丙二醛水平、细胞内铁离子聚集、基质金属蛋白酶3的mRNA表达均升高(P<0.05),谷胱甘肽水平及Ⅱ型胶原和聚集蛋白聚糖的mRNA表达减少(P<0.05);与模型组比较,铁抑素1组细胞内丙二醛水平、细胞内铁离子聚集、基质金属蛋白酶3的mRNA表达均降低(P<0.05),谷胱甘肽水平及Ⅱ型胶原和聚集蛋白聚糖的mRNA表达升高(P<0.05)。(2)扫描电镜下载药水凝胶呈现疏松多孔结构,内部含有大小不一的空泡,该水凝胶具有良好的药物缓释性能。与模型组相比,游离药物组和载药水凝胶组小鼠的疼痛均有缓解,炎症因子、丙二醛水平降低(P<0.05),谷胱甘肽水平与谷胱甘肽过氧化物酶4、溶质载体家族7成员11 mRNA表达均升高(P<0.05),并且载药水凝胶的作用强于游离药物。(3)结果表明,铁抑素1通过调节氧化应激和铁死亡相关基因表达发挥髓核细胞保护作用,治疗小鼠腰椎间盘突出症。

关键词： Chlorine dioxide (ClO2)   Human astrovirus (HAstV)   Immunofluorescence (IF) assay   Oyster   Peracetic acid (PAA)   Ultraviolet-C (UV-C)   Viral inactivation  

摘要： This study evaluated the antiviral efficacy of chlorine dioxide (ClO₂) and peracetic acid (PAA) as chemical disinfectants, and UV-C irradiation as a physical treatment, against HAstV-1, applied individually or sequentially on three relevant matrices: oysters, stainless steel (SS; food-contact surface), and low-density polyethylene (LDPE; packaging surface). Infectious viral titers were quantified using a modified immunofluorescence (IF) assay, which was optimized for oyster matrices in this study by adjusting virus adsorption time, antibody conditions, and buffer composition to enhance reproducibility and signal clarity. Treatment with ClO₂ (200 ppm, 5 min) and PAA (200 ppm, 1 min) resulted in greater reductions (>2 log₁₀ FFU/mL) on oyster tissues compared to UV-C irradiation (1800 mJ/cm²; 1.8 log₁₀ FFU/mL). HAstV-1 levels dropped below the detection limit when treated with ≥700 ppm ClO₂ and ≥1500 ppm PAA on SS and ≥300 ppm ClO₂ and ≥900 ppm PAA on LDPE, respectively. UV-C treatment at 3600 mJ/cm² achieved reductions of 1.37 and 1.63 log₁₀ FFU/mL on SS and LDPE, respectively. Sequential treatments combining ClO₂ (50 ppm) or PAA (150 ppm) with subsequent UV-C irradiation (600 mJ/cm²) significantly enhanced HAstV-1 inactivation on oyster surfaces, yielding additional reductions of 0.96 and 0.57 log₁₀ FFU/mL, respectively. Texture and color analyses indicated slight decreases in hardness and chewiness (p < 0.05); however, no significant differences were observed in elasticity or color parameters (p > 0.05). The modified IF assay demonstrated improved reproducibility and signal clarity and was successfully applied for detecting infectious HAstV-1 in oyster matrices.

关键词： XRE-Type transcriptional regulator   Prodigiosin synthesis   Regulatory mechanism   Serratia marcescens  

摘要： The gram-negative bacterium Serratia marcescens produces various secondary metabolites, including prodigiosin, althiomycin, and serratamolide. Among these, prodigiosin exhibits multiple biological activities such as antibacterial, anticancer, and immunosuppressive properties. Nevertheless, our understanding of the regulatory mechanisms governing prodigiosin biosynthesis in S. marcescens remains incomplete. Here, an HTH_XRE family transcription factor, BVG90_RS12600 (designated ProR), was identified as a positive regulator of prodigiosin production. Disruption of proR drastically reduced prodigiosin yield, with the ΔproR mutant producing only 2.68% of that produced by the wild-type strain JNB5-1. Integrated analysis employing comparative transcriptomics, RT-qPCR, electrophoretic mobility shift assays (EMSA), and transcriptional fusion reporters elucidated the molecular mechanism whereby ProR regulates prodigiosin biosynthesis in S. marcescens. Mechanistically, ProR binds to the promoter region of psrA, which encodes a key transcriptional activator of prodigiosin synthesis, thereby upregulating PsrA expression. This, in turn, enhances transcription of the prodigiosin biosynthetic (pig) operon, establishing ProR as a positive regulator in the prodigiosin biosynthesis pathway. Our findings provide a framework for systematically elucidating the complex regulatory network governing prodigiosin biosynthesis in S. marcescens and for rational engineering of optimized microbial chassis for its overproduction.

关键词： Anticancer potential   Fingerprint visualization   Fluorescence applications   Oxadiazole fluorophores   Security applications   Thermogravimetric analysis  

摘要： Two novel donor–acceptor oxadiazole-based fluorophores, FLO-1 and FLO-2, were designed, synthesized, and systematically investigated as multifunctional materials for forensic and security applications and in silico anticancer evaluation. The photophysical properties were examined using UV–visible absorption and fluorescence spectroscopy in solvents of varying polarity, revealing pronounced intramolecular charge-transfer (ICT) behavior, large Stokes shifts, and solvent-dependent emission tunability. FLO-2 exhibited red-shifted absorption and emission, enhanced solvatochromism, and superior fluorescence performance compared to FLO-1, which was attributed to its stronger donor unit and extended π-conjugation. Theoretical investigations, including density functional theory (DFT), frontier molecular orbital analysis, molecular electrostatic potential (MEP), reduced density gradient (RDG), and electron localization function (ELF) analyses, confirmed the donor–π-acceptor architecture and highlighted the efficient charge separation and electronic delocalization, particularly in FLO-2. Practical applicability was demonstrated through successful latent fingerprint visualization on porous and non-porous surfaces using FLO-1 as well as the development of an FLO-2-based fluorescent security ink that remained invisible under daylight and exhibited strong, stable fluorescence under UV illumination. Thermogravimetric analysis confirmed adequate thermal stability for forensic and security applications. Molecular docking studies against the human topoisomerase IIβ-DNA complex and DNA strands demonstrated favorable binding affinities comparable to those of reference anticancer drugs, indicating potential dual activity as topoisomerase IIβ inhibitors and DNA intercalators.

关键词： 1-Propanol   Culture-dependent validation   Environmental factors   Metabolic pathways   Metagenomics   Microbial community  

摘要： 1-Propanol is a crucial flavor compound in Jiang-flavor Baijiu, yet the key microbial pathways and environmental factors controlling its synthesis have not been systematically investigated. Using an integrated approach of metagenomics and culture-dependent techniques, this study identified the key microbes, pathways, and factors controlling 1-propanol synthesis. The highest 1-propanol level was detected in first-round base Baijiu, with rapid accumulation during early pit fermentation. Metagenomics revealed the propanoate pathway as the dominant route, primarily contributed by Limosilactobacillus, while Pichia and Saccharomyces were key providers of pyruvate decarboxylase in the citramalate and threonine pathways. Pure-culture validation confirmed that L. panis MR32 predominantly utilizes 1,2-propanediol as the precursor, while yeasts such as P. kudriavzevii 2J2 and S. cerevisiae LB7A prefer the 2-ketobutyrate pathway. Environmental tests revealed optimal 1-propanol production by L. panis MR32 at pH 5.5 and increasing yields with temperature (25–45 °C). In contrast, most yeasts produced the most 1-propanol at 30 °C, beyond which yields declined, with only P. kudriavzevii 2J2 and I. orientalis IO tolerating high lactic acid. Our findings clarify the microbial division of labor and environmental drivers of 1-propanol formation, enabling targeted fermentation control.