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Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang liu Xiang Li Shen Du Ming Gao Yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

The complex effects of miR-146a in the pathogenesis of Alzheimer's disease

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Neural Regeneration Research 2025年第5期20卷 1309-1323页

作者： Yunfan Long Jiajia liu Yu Wang Haidong Guo Guohong Cui Department of Neurology Shanghai No.9 People’s HospitalShanghai Jiaotong University School of MedicineShanghaiChina Academy of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina School of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina Department of Neurology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghaiChina

Alzheimer's disease is a neurodegenerative disorder characterized by cognitive dysfunction and behavioral *** plaques formed through the extracellular deposition of amyloid-βproteins,as well as neurofibrillary tangles formed by the intracellular deposition of hyperphosphorylated tau proteins,comprise two typical pathological features of Alzheimer's *** symptomatic treatment,there are no effective therapies for delaying Alzheimer's disease ***(miR)are small,non-coding RNAs that negatively regulate gene expression at the transcriptional and translational levels and play important roles in multiple physiological and pathological ***,miR-146a,a NF-κB-regulated gene,has been extensively implicated in the development of Alzheimer's disease through several *** has demonstrated substantial dysregulation of miR-146a both during the initial phases and throughout the progression of this *** R-146a is believed to reduce amyloid-βdeposition and tau protein hyperphosphorylation through the TLR/IRAK1/TRAF6 pathway;however,there is also evidence supporting that it can promote these processes through many other pathways,thus exacerbating the pathological manifestations of Alzheimer's *** has been widely reported that miR-146a mediates synaptic dysfunction,mitochondrial dysfunction,and neuronal death by targeting m RNAs encoding synapticrelated proteins,mitochondrial-related proteins,and membrane proteins,as well as other *** the impact on glial cells,miR-146a also exhibits differential *** one hand,it causes widespread and sustained inflammation through certain pathways,while on the other hand,it can reverse the polarization of astrocytes and microglia,alleviate neuroinflammation,and promote oligodendrocyte progenitor cell differentiation,thus maintaining the normal function of the myelin sheath and exerting a protective effect on *** this review,we provide a

关键词： Alzheimer's disease amyloid-β glial cells microRNAs miR-146a neuroinflammatory

The Hardness of Amorphous Si-DLC Films by Molecular Dynamics Simulations

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Journal of Wuhan University of Technology(Materials Science) 2013年第3期28卷 444-448页

作者：兰惠清 liu can School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Institute of Higher Energy Physics Chinese Academy of Sciences

Silicon-doped diamond-like carbon （Si-DLC） films possess the potential to improve wear performance of DLC films in humid atmospheres and at higher temperatures. But many experimental results of Si-DLC films show that their structure and mechanical properties have changed greatly with the increasing silicon content. Therefore, molecular dynamics （MD） simulations were used to generate hydrogen-free Si-DLC films and study their nano-indentation process under the interaction of a diamond indenter. The results show that sp3/sp2（C）（only carbon atoms） always decreases with the increasing silicon content. But sp3/sp2（C＋Si） ratio increases firstly and reaches a maximum at the silicon content of 0.2, and then decreases with the further increase of the silicon content. Bulk modulus and hardness of the Si-DLC films both decrease with the increasing of the silicon content, which has the same trend with Papakonstantinou and Ikeyama＇s results. It is concluded that the hardness of the Si-DLC films is dependent on sp3/sp2（C）, not sp3/sp2（C＋Si）.

关键词： diamond-like carbon film molecular dynamics silicon hardness

Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin liu Run Hou Chenghao Wu Ruishan Xie Shujun Chen College of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China Chongqing Research Institute of Beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

初中生认知控制对替代性攻击行为的影响:激惹和触发的情境边界条件

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心理学报 2025年第1期57卷 36-57页

作者：林爽程塨渌刘文白学军天津师范大学心理学部天津300387 辽宁师范大学心理学院大连116029 广西师范大学教育学部桂林541004

本研究通过3个实验探索了初中生认知控制对替代性攻击行为的影响以及认知控制影响替代性攻击行为的激惹和触发情境边界条件。实验1考察了一般性认知控制对替代性攻击行为的影响,结果发现一般性认知控制不能有效降低替代性攻击行为的攻... 详细信息

本研究通过3个实验探索了初中生认知控制对替代性攻击行为的影响以及认知控制影响替代性攻击行为的激惹和触发情境边界条件。实验1考察了一般性认知控制对替代性攻击行为的影响,结果发现一般性认知控制不能有效降低替代性攻击行为的攻击比例。实验2探讨了特异性认知控制对替代性攻击行为的有效抑制作用,结果发现无论在高激惹情境还是低激惹情境,主动控制和反应性控制启动条件下的替代性攻击行为均显著低于基线水平。实验3则探究了特异性认知控制抑制替代性攻击行为的激惹和触发情境边界条件,结果发现特异性认知控制、激惹情境、触发情境三者的交互作用显著,激惹和触发情境能够有效调节特异性认知控制对替代性攻击行为的影响。而且,在高激惹高触发和高激惹低触发情境下,主动性控制减基线的攻击比例显著高于反应性控制减基线,但在低激惹高触发和低激惹低触发情境下主动性控制减基线的攻击比例与反应性控制减基线不存在显著差异。此外,高激惹高触发情境下主动性控制减基线的攻击比例是所有条件下最高的。以上结果说明,特异性认知控制能够有效抑制初中生的替代性攻击行为,其中主动性控制的情境边界出现在高激惹高触发情境。

关键词：认知控制替代性攻击行为激惹情境触发情境情境边界条件

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敌草快对鸡输卵管膨大部组织结构、细胞凋亡及繁殖性能相关基因表达的影响

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农业生物技术学报 2025年第1期33卷 146-156页

作者：戴逸园丁香胡威刘犇肖佩怡杨雪郑文亚樊庆灿宜春学院生命科学与资源环境学院江西省高等学校硒农业工程技术研究中心江西绿科农牧科技有限公司

联吡啶类除草剂敌草快(Diquat)作为现代农业生产中常用的农药，极易引起禽类发生氧化应激，为探究敌草快诱导的氧化应激对鸡输卵管膨大部的影响，本研究选取45只健康且体重相近的180日龄康乐黄母鸡(Gallus gallus)，随机分成3组，每组1... 详细信息

联吡啶类除草剂敌草快(Diquat)作为现代农业生产中常用的农药，极易引起禽类发生氧化应激，为探究敌草快诱导的氧化应激对鸡输卵管膨大部的影响，本研究选取45只健康且体重相近的180日龄康乐黄母鸡(Gallus gallus)，随机分成3组，每组15只。各组鸡均饲喂基础饲粮且自由饮水，经1周适应性饲养后，实验组分别一次性腹腔注射10和20 mg/kg BW(body weight,体重)的敌草快，对照组腹腔注射等剂量的生理盐水，21 d后采集输卵管膨大部组织，利用抗氧化功能检测试剂盒检测抗氧化指标，利用苏木素-伊红(hematoxylin-eosin, HE)染色技术观察病理损伤，利用免疫组织化学(immunohistochemistry, IHC)技术检测相关蛋白的分布，利用qPCR和Western blot技术检测细胞凋亡和繁殖性能相关基因及蛋白的表达。结果显示，敌草快组的输卵管膨大部中过氧化氢酶(catalase, CAT)、总超氧化物歧化酶(total superoxide dismutase, T-SOD)活性显著降低(P<0.05)，丙二醛(malondialdehyde, MDA)浓度显著升高(P<0.05)。HE染色结果显示，敌草快组的输卵管膨大部管径减小，固有层细胞分布稀疏，黏膜上皮游离面纤毛受损，敌草快20 mg/kg组的黏膜上皮细胞出现空泡化。IHC结果显示，敌草快组的输卵管膨大部黏膜上皮和固有层中增殖细胞核抗原(proliferating cell nuclear antigen, PCNA)的染色强度降低，无翅型鼠乳腺癌病毒整合位点4(Wingless-related murine mammary tumor virus integration site 4, Wnt4)在黏膜上皮游离面的染色强度也降低。qPCR结果显示，敌草快20 mg/kg组的输卵管膨大部中抗凋亡相关基因B-细胞淋巴瘤-2(B-cell lymphoma-2, Bcl-2)表达水平显著下调(P<0.05)，敌草快组促凋亡相关基因Bcl-2相关X蛋白(Bcl-2 associated X protein, Bax)和半胱氨酸蛋白酶3(Caspase3)的基因表达水平及Bax/Bcl-2均显著上调(P<0.05)；繁殖性能相关基因透明带精子结合蛋白2(zona pellucida sperm-binding protein 2, ZP2)和Wnt4的基因表达水平显著下调(P<0.05)。Western blot结果显示，Bcl-2、Bax、Caspase3、ZP2和Wnt4的蛋白表达水平与基因表达的变化趋势基本一致。上述研究结果表明，敌草快能够诱导鸡输卵管膨大部发生氧化应激和细胞凋亡，进而损伤膨大部组织结构及抑制繁殖性能相关基因的表达。本研究为缓解联吡啶类农药对禽类输卵管的损伤及保护繁殖性能提供理论参考。

关键词：敌草快氧化应激母鸡输卵管膨大部细胞凋亡繁殖性能相关基因

Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex

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Neural Regeneration Research 2025年第10期20卷 2923-2937页

作者： Yan Li Peng Hao Hongmei Duan Fei Hao wen Zhao Yudan Gao Zhaoyang Yang Kwok-Fai So Xiaoguang Li Department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina China Rehabilitation Science Institute China Rehabilitation Research CenterBeijing Key Laboratory of Neural Injury and RehabilitationBeijingChina Center of Neural Injury and Repair Beijing Institute for Brain DisordersBeijingChina Beijing Key Laboratory for Biomaterials and Neural Regeneration School of Engineering MedicineBeihang UniversityBeijingChina Guangdong-HongKong-Macao Institute of CNS Regeneration Ministry of Education CNS Regeneration Collaborative Joint LaboratoryJinan UniversityGuangzhouGuangdong ProvinceChina Bioland Laboratory(Guangzhou Regenerative Medicine and Health Guangdong Laboratory) GuangzhouGuangdong ProvinceChina Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences The University of Hong KongHong Kong Special Administration RegionChina Center for Brain Science and Brain-Inspired Intelligence Guangdong-HongKong-Macao Greater Bay AreaGuangzhouGuangdong ProvinceChina Co-innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina

The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after ***,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains *** this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic *** findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated ***,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain *** findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.

关键词： adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation

Quantitative analysis of CO_(2) embodiment in international trade:An overview of emerging literatures

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Frontiers of Environmental Science & Engineering 2009年第1期3卷 12-19页

作者： Xianbing liu can WANG Kansai Research Centre Institute for Global Environmental Strategies(IGES)Kobe 651-0073Japan Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China

The increasing volume of CO_(2) embodiment in international trade adds a layer of complexity to environmental policies and has raised arguments on the traditional production based responsibility for CO_(2) *** order to help understand the quantity of CO_(2) embodiment in trade and its policy implications,this paper gives observations to recently emerging literatures that quantitatively discuss CO_(2) embodiment in *** analytical approaches share the principle of using input and output modeling but vary dramatically in study boundary and estimation *** calculations can be roughly categorized into three types:direct quantification of CO_(2) embodiments in multiregional trade,direct quantification of CO_(2) embodiment in bilateral trade,and indirect analysis by comparing the scenarios with or without *** practical estimations strongly rely on trade partner selection and data *** obvious imbalance of net CO_(2) embodiment in the commodity trade between major developed countries and developing economies as a whole was confirmed by these *** taxes and other possible limitations on CO_(2) emissions have been *** consistency across the calculations could be enhanced by systematic analyses in more detail to convince the international community to take binding commitments for the reduction of global CO_(2) emissions.

关键词： CO_(2)embodiment international trade quantitative estimation analytical approach

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction