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Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 193-208页

作者： k.MUHAMMAD M.SARFRAZ Department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(MHD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in MATHEMATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

关键词： convective boundary condition Darcy-Forchheimer medium hybrid nanofluid Joule heating magnetohydrodynamic (MHD) numerical solution squeezing flow regression analysis O361 O175.2

A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi Yun-Hao Xu Ming-Hui Chen Peng Zhao Wen-Bo Deng ji Xiong kai Guo Ya-Qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou Wei-jin jiang ji Yu Mao-Jun Yao Yun-Tong Li Hunan Provincial key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

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认知空间映射及其神经机制

心理科学进展 2025年第1期33卷 62-76页

作者：吴际李会杰南宁师范大学教育科学学院南宁530001 中国科学院行为科学重点实验室(中国科学院心理研究所) 北京100101 中国科学院大学心理学系北京100049

认知地图不仅可以映射物理空间,还可以支持认知空间映射,形成包括感知空间、情景记忆空间、概念空间和社会空间等在内的跨不同信息领域的地图式表征。认知空间映射的神经机制包括海马体对潜在结构的抽象和概括、支持分布式位置地图的生... 详细信息

认知地图不仅可以映射物理空间,还可以支持认知空间映射,形成包括感知空间、情景记忆空间、概念空间和社会空间等在内的跨不同信息领域的地图式表征。认知空间映射的神经机制包括海马体对潜在结构的抽象和概括、支持分布式位置地图的生成、将信息与背景结构捆绑,以及海马体与其它脑区的协同。未来研究应关注预测性的认知空间地图、海马体对不同精度和层级信息的表征、认知空间映射微观和介观层面的研究空缺以及物理空间和认知空间映射的共同机制和特异性机制等问题。

关键词：认知地图网格细胞位置细胞海马体

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集成深度强化学习在股票指数投资组合优化中的应用分析

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计算机科学与探索 2025年第1期19卷 237-244页

作者：冀中张文嘉天津大学电气自动化与信息工程学院天津300072 天津大学佐治亚理工深圳学院天津300072

基于集成深度强化学习的投资组合选择是当前量化金融领域的关键技术之一。然而,目前采用上一窗口阶段最优指标决定下一阶段代理的集成滚动窗口方法存在一定的滞后性。为了有效应对这一不足,提出了双层嵌套集成深度强化学习方法。该方法... 详细信息

基于集成深度强化学习的投资组合选择是当前量化金融领域的关键技术之一。然而,目前采用上一窗口阶段最优指标决定下一阶段代理的集成滚动窗口方法存在一定的滞后性。为了有效应对这一不足,提出了双层嵌套集成深度强化学习方法。该方法对三种代理(优势演员-评论员、深度确定性策略梯度和近端策略优化)进行两层嵌套模式,第一层集成通过最优化夏普比率进行阶段模型选择,第二层通过加权投票的方法集成三种深度强化学习算法,从单次训练中收集多个模型快照,在训练期间利用这些模型进行集成预测。分别对上证50投资指数和道琼斯指数及其包含的股票进行了投资组合研究,将持有指数被动策略和均值方差投资组合策略作为基线策略。实验采用了投资组合价值、年化回报率、年化波动率、最大回撤和夏普比率等指标作为对比指标。结果表明,所提出的集成方法在实用性和有效性上表现出较好的性能。

关键词：股票投资组合交易策略深度强化学习双层嵌套集成深度强化学习方法集成学习

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NECAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno Michael k.E.Schafer Sudena Wang Michael J.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NECAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NECAB2 interacts with predominantly striatal G-protein-coupled receptors, while NECAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NECAB proteins exhibit distinct subcellular localizations: NECAB1 is found in the nucleus and cytosol, NECAB2 resides in endosomes and the plasma membrane, and NECAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NECAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NECAB proteins by controlling the availability of protein–protein interaction domains situated between the EF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium EF hand mitochondria nervous system signal transduction

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Role of nutrition in diabetes mellitus and infections

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World Journal of Clinical Cases 2025年第3期13卷 1-8页

作者： Xue-Lu Yu Li-Yun Zhou Xiao Huang Xin-Yue Li Ming-ke Wang ji-Shun Yang Naval Medical Center of PLA Naval Medical UniversityShanghai 200052China

In this editorial,we have commented on the article that has been published in the recent issue of World Journal of Clinical *** authors have described a case of unilateral thyroid cyst and have opined that the acute onset of infection may be linked to diabetes mellitus(DM).We have focused on the role of nutrition in the association between DM and *** with DM are at a high risk of infection,which could also be attributed to nutrition-related *** interventions for patients with diabetes are mainly based on a low-calorie diet,which can be achieved by adhering to a low-carbohydrate ***,dietary fiber supplementation is recommended to maintain the diversity of the gut ***,high-quality protein can prevent the increased risk of infection due to *** of vitamins C,vitamins A,vitamins D,and folic acid improves blood sugar control and facilitates immune *** deficiencies augment the risk of infection,but the relationship with diabetes is mostly U-shaped and a good intake should be maintained.

关键词： Diabetes mellitus Infection Macronutrients Vitamins Minerals

青藏高原湖泊沉积物细菌群落的盐度梯度分布格局及驱动因素

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湖泊科学 2025年第1期37卷 238-252,I0025,I0026页

作者：陈幸婷杜晨亮王建军沈吉南京大学地理与海洋科学学院南京210023 中国科学院南京地理与湖泊研究所湖泊与流域水安全重点实验室南京211135

盐度是影响湖泊细菌群落最重要的环境因子之一,揭示盐度对细菌群落变化的影响对于深入理解水生生态系统细菌群落具有重要意义。本研究以青藏高原西南部的22个湖泊为对象,探讨33个沉积物样本的细菌丰富度、均匀度和群落组成,分析其随盐... 详细信息

盐度是影响湖泊细菌群落最重要的环境因子之一,揭示盐度对细菌群落变化的影响对于深入理解水生生态系统细菌群落具有重要意义。本研究以青藏高原西南部的22个湖泊为对象,探讨33个沉积物样本的细菌丰富度、均匀度和群落组成,分析其随盐度梯度的变化规律,阐明其潜在的环境驱动因素。结果表明,变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)和放线菌门(Actinobacteria)是青藏高原湖泊沉积物中的优势细菌门类,相对丰度分别为46.54%、12.41%和7.23%,总和达到整个细菌门类的66.18%。对于细菌α多样性,物种丰富度和均匀度均随盐度增加呈显著下降趋势;对于细菌β多样性,基于非度量多维排列分析,根据盐度可以将细菌群落分布分为3个显著的独立簇,分别对应淡水、咸水和高盐环境。Mantel检验结果表明,相较于地理距离,湖泊沉积物细菌群落Bray-Curtis不相似性随盐度的变化更为显著。方差分解分析和随机森林分析结果表明,细菌物种丰富度、均匀度和群落组成变化的最佳预测因子为盐度和磷酸盐等化学因素,整体贡献率分别为72.98%、59.82%和60.83%,其中盐度是丰富度、均匀度和群落组成变化的主要驱动因素,其相对贡献率分别为45.47%、79.18%和79.50%。基于结构方程模型进一步分析表明,湖泊沉积物细菌丰富度、均匀度和群落组成变化均受到盐度直接或间接的影响。本研究结果充分探讨了盐度对细菌群落变化的影响,揭示了青藏高原湖泊沉积物细菌组成及其环境驱动因素,可为理解湖泊生态系统细菌群落对环境变化的响应提供科学支撑。

关键词：湖泊细菌群落物种丰富度物种均匀度群落组成环境驱动因素青藏高原

Dextran-modified iron oxide nanoparticles

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China Particuology 2007年第1期5卷 162-168页

作者： jií Hradil Alexander Pisarev Michal Babi Daniel Hork Institute of Macromolecular Chemistry Academy of Sciences of the Czech Republic Heyrovsky Sq. 2 162 06 Prague Czech Republic

Dextran-modified iron oxide nanoparticles were prepared by precipitation of Fe（Ⅱ） and Fe（Ⅲ） salts with ammonium hydroxide by two methods. Iron oxide was precipitated either in the presence of dextran solution, or the dextran solution was added after precipitation. In the second method, the iron oxide particle size and size distribution could be controlled depending on the concentration of dextran in the solution. The nanoparticles were characterized by size-exclusion chromatography, transmission electron microscopy and dynamic light scattering. Optimal conditions for preparation of stable iron oxide colloid particles were determined, The dextran/iron oxide ratio 0-0,16 used in precipitation of iron salts can be recommended for synthesis of nanoparticles suitable for biomedical applications, as the colloid does not contain excess dextran and does not coagulate.

关键词： Iron oxide Nanoparticles Dextran Size-exclusion chromatography Particle size

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