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Synthesis of Cyclohexyl Acrylate Derivative and Its Evaluation as a Plasticizer for PVC
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作者 Zhihong Wang Wei Wei +5 位作者 Song Wang Bingli Zhou Yingle Chen Liu Yang Qiaoguang Li Lei Zeng 《Journal of Polymer Materials》 2025年第2期449-462,共14页
In this study,3,4-Epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate(ECC)and refined Camellia oleifera seed oil(RCOSO)obtained from saponification and acidified hydrolysis has been used as raw materials to perform ... In this study,3,4-Epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate(ECC)and refined Camellia oleifera seed oil(RCOSO)obtained from saponification and acidified hydrolysis has been used as raw materials to perform ring-opening reactions for the preparation of cyclohexyl acrylate derivative(CAR).The structure of the synthesized product was characterized using infrared spectroscopy,Raman spectroscopy,and nuclear magnetic resonance spectroscopy.CAR was employed as a plasticizer to produce modified polyvinyl chloride(PVC)films,dioctyl phthalate plasticizer(DOP)used in reference samples to investigate the influence of different plasticizer molecular structures on the properties of PVC films.Observation suggested that(1)CAR plasticizer was successfully synthesized;(2)CAR can interact with PVC,exhibiting good compatibility;(3)PVC films contain CAR showed improved thermal stability,hydrophilicity,and tensile strength.Therefore,CAR has the potential to replace DOP as a plasticizer for PVC. 展开更多
关键词 Polyvinyl chloride Camellia oleifera seed oil biobased plasticizer
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透析用留置针在血液透析患者自体动静脉内瘘启用初期的应用研究
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作者 骆芬霞 周建芳 +3 位作者 胡婷 姚洁 徐春英 支剑青 《中国血液净化》 2026年第1期78-82,共5页
目的观察透析用留置针在血液透析患者自体动静脉内瘘(arteriovenous fistula,AVF)启用初期的安全性及应用效果。方法纳入2021年3月─2024年3月的新AVF启用患者,按随机数字表法分为试验组和对照组。试验组采用透析用留置针穿刺,对照组采... 目的观察透析用留置针在血液透析患者自体动静脉内瘘(arteriovenous fistula,AVF)启用初期的安全性及应用效果。方法纳入2021年3月─2024年3月的新AVF启用患者,按随机数字表法分为试验组和对照组。试验组采用透析用留置针穿刺,对照组采用金属针穿刺。2组分别穿刺2个月(动、静脉各穿刺26次)。比较2组主要、次要结局指标及安全性指标的差异。结果试验组完成38例,对照组完成40例。试验组透析中动脉压(t=6.646,P<0.001)、静脉压(t=6.708,P<0.001)及血肿发生率(χ=10.789,P=0.001)低于对照组,10 min止血率(χ^(2)=4.347,P=0.037)及舒适度(t=9.199,P<0.001)高于对照组。2组均无针滑出、针刺伤、动脉瘤、感染及过敏事件。结论AVF启用初期采用透析用留置针穿刺安全可行,在保证穿刺成功率、充足血流量及透析充分性的前提下,可减少血肿的发生,提高患者舒适度,缩短拔针后止血时间。 展开更多
关键词 血液透析 自体动静脉内瘘 透析用留置针
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圆形截面并联式屈曲约束支撑设计方法及力学性能
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作者 李亮 牛飞宇 +3 位作者 黄俊 唐浩龙 刘岩 南晓辉 《工程力学》 北大核心 2026年第1期97-108,共12页
该文提出一种圆形截面并联式屈曲约束支撑(CP-BRB),该支撑由内部、外部抗力系统并联组成,且外部抗力系统两端对称设有屈服位移极小且数量众多的微型剪切阻尼器。根据CP-BRB的工作原理,建立了其简化力学模型,并基于最优破坏模式提出了CP-... 该文提出一种圆形截面并联式屈曲约束支撑(CP-BRB),该支撑由内部、外部抗力系统并联组成,且外部抗力系统两端对称设有屈服位移极小且数量众多的微型剪切阻尼器。根据CP-BRB的工作原理,建立了其简化力学模型,并基于最优破坏模式提出了CP-BRB的简化设计方法,推导了轴向刚度、屈服承载力和屈服位移的计算公式。根据文献中多种传统BRB试件,设计了3组CP-BRB算例,采用ABAQUS对其力学性能和破坏模式进行研究。结果表明:数量众多的微型剪切阻尼器的屈服位移均远小于内部圆钢棒的屈服位移,CPBRB的力学性能具有显著的多阶段屈服特性;CP-BRB的滞回曲线饱满,延性较好,耗能能力强,在轴力作用下,并联的内部和外部抗力系统可形成两道抗力防线;与传统BRB相比,CP-BRB的屈服位移相当于传统BRB的8%~29%,在地震作用下能更早的进入塑性状态,更好的对主体结构进行保护,有良好的工程应用前景;理论结果和有限元结果吻合良好,提出的计算公式结果准确,可用于工程实际。 展开更多
关键词 屈曲约束支撑 抗力系统 微型剪切阻尼器 力学模型 滞回曲线 塑性状态
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纸材在综合材料绘画中的设计应用研究
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作者 郭红娟 王佳鹏 丁言伟 《鞋类工艺与设计》 2026年第1期96-98,共3页
近年来,随着“纸艺”在全球范围快速发展,众多艺术家将纸张作为创作核心,展示出纸材独特的可塑性和表现力。本文以纸材为研究对象,分析纸材与其他媒介的结合方式及其对画面质感、空间层次和情感表达的创新影响,结合现代实践创作案例,探... 近年来,随着“纸艺”在全球范围快速发展,众多艺术家将纸张作为创作核心,展示出纸材独特的可塑性和表现力。本文以纸材为研究对象,分析纸材与其他媒介的结合方式及其对画面质感、空间层次和情感表达的创新影响,结合现代实践创作案例,探讨其在综合材料绘画中的设计应用方式及建议,为综合材料绘画创作提供参考思路。 展开更多
关键词 纸材 综合材料绘画 可塑性 设计 视觉语言
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A Novel Plasticizer for the Preparation of Thermoplastic Starch 被引量:1
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作者 Jin Hui YANG Jiu Gao YU Xiao Fei MA 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第1期133-136,共4页
in this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch (TPS). FT-IR expressed that ethylenebisformamide formed stronger and stable hydrogen... in this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch (TPS). FT-IR expressed that ethylenebisformamide formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch. X-ray diffraction (XRD) showed that the typical A-style crystallinity in the native starch has been destructed. By scanning electron microscope (SEM) native cornstarch granules were proved to transfer to a homogeneous system. After being stored for one week at RH=33%, the mechanical properties of EPTPS was also studied. The elongation reached to 264% utmost. As a novel plasticizer, ethylenebisformamide would be practical to extend TPS application scopes. 展开更多
关键词 Thermoplastic starch ethylenebisformamide novel plasticizer.
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Metabolic reprogramming of astrocytes:Emerging roles of lactate 被引量:1
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作者 Zeyu Liu Yijian Guo +2 位作者 Ying Zhang Yulei Gao Bin Ning 《Neural Regeneration Research》 2026年第2期421-432,共12页
Lactate serves as a key energy metabolite in the central nervous system,facilitating essential brain functions,including energy supply,signaling,and epigenetic modulation.Moreover,it links epigenetic modifications wit... Lactate serves as a key energy metabolite in the central nervous system,facilitating essential brain functions,including energy supply,signaling,and epigenetic modulation.Moreover,it links epigenetic modifications with metabolic reprogramming.Nonetheless,the specific mechanisms and roles of this connection in astrocytes remain unclear.Therefore,this review aims to explore the role and specific mechanisms of lactate in the metabolic reprogramming of astrocytes in the central nervous system.The close relationship between epigenetic modifications and metabolic reprogramming was discussed.Therapeutic strategies for targeting metabolic reprogramming in astrocytes in the central nervous system were also outlined to guide future research in central nervous system diseases.In the nervous system,lactate plays an essential role.However,its mechanism of action as a bridge between metabolic reprogramming and epigenetic modifications in the nervous system requires future investigation.The involvement of lactate in epigenetic modifications is currently a hot research topic,especially in lactylation modification,a key determinant in this process.Lactate also indirectly regulates various epigenetic modifications,such as N6-methyladenosine,acetylation,ubiquitination,and phosphorylation modifications,which are closely linked to several neurological disorders.In addition,exploring the clinical applications and potential therapeutic strategies of lactic acid provides new insights for future neurological disease treatments. 展开更多
关键词 ASTROCYTE epigenetic modifications inflammation LACTATE lactylation METABOLIC PLASTICITY regeneration treatment
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Hippocampal damage through foreign body placement in organotypic cultures leads to plastic responses in newly born granule cells
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作者 Tassilo Jungenitz Lukas Frey +2 位作者 Sophia Kirscht Stephan W.Schwarzacher Angélica Zepeda 《Neural Regeneration Research》 2026年第3期1142-1150,共9页
The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves gl... The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves global alterations,making understanding plastic responses triggered by local damage difficult.One key feature of the dentate gyrus is that it contains a well-defined neurogenic niche,the subgranular zone,and beyond neurogenesis,newly born granule cells may maintain a“young”phenotype throughout life,adding to the plastic nature of the structure.Here,we present a novel experimental model of local brain damage in organotypic entorhino-hippocampal cultures that results in the activation of adjacent newly born granule cells.A small piece of filter paper was placed on the surface of the granule cell layer of the dentate gyrus,which evoked a foreign body reaction of astrocytes,along with the activation of local young neurons expressing doublecortin.Forty-eight hours after foreign body placement,the number of doublecortin-immunoreactive cells increased in the subgranular zone in the direct vicinity of the foreign body,whereas overall increased doublecortin immunoreactivity was observed in the granule cell layer and molecular layer of the dentate gyrus.Foreign body placement in the pyramidal layer of the CA1 region evoked a comparable local astroglial reaction but did not lead to an increase in doublecortin-immunoreactive in either the CA1 region or the adjacent dentate gyrus.Seven days after foreign body placement in the dentate gyrus,the increase in doublecortin-immunoreactivity was no longer observed,indicating the transient activation of young cells.However,7 days after foreign body placement,the number of doublecortin-immunoreactive granule cells coimmunoreactive for calbindin was lower than that under the control conditions.As calbindin is a marker for mature granule cells,this result suggests that activated young cells remain at a more immature stage following foreign body placement.Live imaging of retrovirally green fluorescent protein-labeled newly born granule cells revealed the orientation and growth of their dendrites toward the foreign body placement.This novel experimental model of foreign body placement in organotypic entorhino-hippocampal cultures could serve as a valuable tool for studying both glial reactivity and neuronal plasticity,specifically of newly born neurons under controlled in vitro conditions. 展开更多
关键词 ASTROCYTE brain plasticity dendritic plasticity dentate gyrus focal brain injury hippocampus NEUROPLASTICITY NEUROREPAIR newborn granule cells regeneration REORGANIZATION
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Neuronal plasticity and its role in Alzheimer's disease and Parkinson's disease
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作者 Israt Jahan Mohammad Harun-Ur-Rashid +4 位作者 MdAminul Islam Farhana Sharmin Soad K.Al Jaouni Abdullah M.Kaki Samy Selim 《Neural Regeneration Research》 2026年第1期107-125,共19页
Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinso... Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease,this plasticity is disrupted,leading to cognitive and motor deficits.This review explores the mechanisms of neuronal plasticity and its effect on Alzheimer's disease and Parkinson's disease.Alzheimer's disease features amyloid-beta plaques and tau tangles that impair synaptic function,while Parkinson's disease involves the loss of dopaminergic neurons affecting motor control.Enhancing neuronal plasticity offers therapeutic potential for these diseases.A systematic literature review was conducted using databases such as PubMed,Scopus,and Google Scholar,focusing on studies of neuronal plasticity in Alzheimer's disease and Parkinson's disease.Data synthesis identified key themes such as synaptic mechanisms,neurogenesis,and therapeutic strategies,linking molecular insights to clinical applications.Results highlight that targeting synaptic plasticity mechanisms,such as long-term potentiation and long-term depression,shows promise.Neurotrophic factors,advanced imaging techniques,and molecular tools(e.g.,clustered regularly interspaced short palindromic repeats and optogenetics)are crucial in understanding and enhancing plasticity.Current therapies,including dopamine replacement,deep brain stimulation,and lifestyle interventions,demonstrate the potential to alleviate symptoms and improve outcomes.In conclusion,enhancing neuronal plasticity through targeted therapies holds significant promise for treating neurodegenerative diseases.Future research should integrate multidisciplinary approaches to fully harness the therapeutic potential of neuronal plasticity in Alzheimer's disease and Parkinson's disease. 展开更多
关键词 Alzheimer's disease long-term depression long-term potentiation NEUROINFLAMMATION neuronal plasticity Parkinson's disease synaptic plasticity
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Brain structural plasticity in large-brained mammals:Not only narrowing roads
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作者 Marco Ghibaudi Alessandro Zanone Luca Bonfanti 《Neural Regeneration Research》 2026年第5期1669-1680,共12页
The capacity of the central nervous system for structural plasticity and regeneration is commonly believed to show a decreasing progression from“small and simple”brains to the larger,more complex brains of mammals.H... The capacity of the central nervous system for structural plasticity and regeneration is commonly believed to show a decreasing progression from“small and simple”brains to the larger,more complex brains of mammals.However,recent findings revealed that some forms of neural plasticity can show a reverse trend.Although plasticity is a well-preserved,transversal feature across the animal world,a variety of cell populations and mechanisms seem to have evolved to enable structural modifications to take place in widely different brains,likely as adaptations to selective pressures.Increasing evidence now indicates that a trade-off has occurred between regenerative(mostly stem cell–driven)plasticity and developmental(mostly juvenile)remodeling,with the latter primarily aimed not at brain repair but rather at“sculpting”the neural circuits based on experience.In particular,an evolutionary trade-off has occurred between neurogenic processes intended to support the possibility of recruiting new neurons throughout life and the different ways of obtaining new neurons,and between the different brain locations in which plasticity occurs.This review first briefly surveys the different types of plasticity and the complexity of their possible outcomes and then focuses on recent findings showing that the mammalian brain has a stem cell–independent integration of new neurons into pre-existing(mature)neural circuits.This process is still largely unknown but involves neuronal cells that have been blocked in arrested maturation since their embryonic origin(also termed“immature”or“dormant”neurons).These cells can then restart maturation throughout the animal's lifespan to become functional neurons in brain regions,such as the cerebral cortex and amygdala,that are relevant to high-order cognition and emotions.Unlike stem cell–driven postnatal/adult neurogenesis,which significantly decreases from small-brained,short-living species to large-brained ones,immature neurons are particularly abundant in large-brained,long-living mammals,including humans.The immature neural cell populations hosted in these complex brains are an interesting example of an“enlarged road”in the phylogenetic trend of plastic potential decreases commonly observed in the animal world.The topic of dormant neurons that covary with brain size and gyrencephaly represents a prospective turning point in the field of neuroplasticity,with important translational outcomes.These cells can represent a reservoir of undifferentiated neurons,potentially granting plasticity within the high-order circuits subserving the most sophisticated cognitive skills that are important in the growing brains of young,healthy individuals and are frequently affected by debilitating neurodevelopmental and degenerative disorders. 展开更多
关键词 adult neurogenesis AMYGDALA brain plasticity cerebral cortex comparative approach evolution immature neurons
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Plasticity meets regeneration during innate spinal cord repair
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作者 Amruta Tendolkar Mayssa H.Mokalled 《Neural Regeneration Research》 2026年第3期1136-1137,共2页
Regenerative capacity of the central nervous system(CNS)is unevenly distributed among vertebrates.While most mammalian species including humans elicit limited repair following CNS injury or disease,highly regenerative... Regenerative capacity of the central nervous system(CNS)is unevenly distributed among vertebrates.While most mammalian species including humans elicit limited repair following CNS injury or disease,highly regenerative vertebrates including urodele amphibians and teleost fish spontaneously reverse CNS damage.Teletost zebrafish(danio rerio)are tropical freshwater fish that proved to be an excellent vertebrate model of successful CNS regeneration.Differential neuronal,glial,and immune injury responses underlie disparate injury outcomes between highly regenerative zebrafish and poorly regenerative mammals.This article describes complications associated with neuronal repair following spinal cord injury(SCI)in poorly regenerative mammals and highlights intersecting modes of plasticity and regeneration in highly regenerative zebrafish(Figures 1 and 2).Comparative approaches evaluating immunoglial SCI responses were recently reviewed elsewhere(Reyes and Mokalled,2024). 展开更多
关键词 urodele amphibians central nervous system central nervous system cns REGENERATION vertebrate model PLASTICITY vertebrates teleost fish
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Synapses and dendritic spines are eliminated in the primary visual cortex of mice subjected to chronic intraocular pressure elevation
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作者 Xinyi Zhang Deling Li +6 位作者 Weiting Zeng Yiru Huang Zongyi Zhan Yuning Zhang Qinyuan Hu Lianyan Huang Minbin Yu 《Neural Regeneration Research》 2026年第3期1236-1248,共13页
Synaptic plasticity is essential for maintaining neuronal function in the central nervous system and serves as a critical indicator of the effects of neurodegenerative disease.Glaucoma directly impairs retinal ganglio... Synaptic plasticity is essential for maintaining neuronal function in the central nervous system and serves as a critical indicator of the effects of neurodegenerative disease.Glaucoma directly impairs retinal ganglion cells and their axons,leading to axonal transport dysfuntion,subsequently causing secondary damage to anterior or posterior ends of the visual system.Accordingly,recent evidence indicates that glaucoma is a degenerative disease of the central nervous system that causes damage throughout the visual pathway.However,the effects of glaucoma on synaptic plasticity in the primary visual cortex remain unclear.In this study,we established a mouse model of unilateral chronic ocular hypertension by injecting magnetic microbeads into the anterior chamber of one eye.We found that,after 4 weeks of chronic ocular hypertension,the neuronal somas were smaller in the superior colliculus and lateral geniculate body regions of the brain contralateral to the affected eye.This was accompanied by glial cell activation and increased expression of inflammatory factors.After 8 weeks of ocular hypertension,we observed a reduction in the number of excitatory and inhibitory synapses,dendritic spines,and activation of glial cells in the primary visual cortex contralateral to the affected eye.These findings suggest that glaucoma not only directly damages the retina but also induces alterations in synapses and dendritic spines in the primary visual cortex,providing new insights into the pathogenesis of glaucoma. 展开更多
关键词 chronic ocular hypertension dendritic spines GLAUCOMA glial cells NEUROINFLAMMATION NEURON retinal ganglion cells synaptic plasticity visual cortex visual pathway
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Revisiting collagen:A breaching point in tumor immunotherapy
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作者 Yi-Da Wang Hai-Yue You +3 位作者 Feng Zhang Xin Ning Jie Mei Yan Zhang 《Life Research》 2026年第1期1-4,共4页
Immunotherapy has brought unprecedented breakthroughs to advanced malignant tumors,yet the immune microenvironment shaped by the tumor stroma has often been underestimated in the traditional focus on the“immune check... Immunotherapy has brought unprecedented breakthroughs to advanced malignant tumors,yet the immune microenvironment shaped by the tumor stroma has often been underestimated in the traditional focus on the“immune checkpoint-T cell”axis.Collagen not only constitutes a mechanical barrier that distinguishes between the periphery and core of solid tumors but also systematically remodels the orientation of metabolism,vasculature,and immune cell phenotypic plasticity through its spatial density,fiber arrangement,and crosslinking patterns(F igure 1)[1,2].Abundant evidence suggests that over-accumulated types I and III collagen drive CD8+T cell exhaustion,NK cell functional inhibition,and tumor-associated macrophage polarization through ligand-receptor networks involving LAIR-1,DDR2,andβ1/β3 integrins[3-6].Mechanistically,collagen engagement of LAIR-1 delivers inhibitory signals in effector lymphocytes,promoting dysfunctional or exhausted states[7-9].In parallel,collagen-β1/β3 integrin signaling activates mechanotransduction pathways(e.g.,FAK/SRC),reducing T-cell motility and immune-tumor contact,while DDR2 activation supports matrix-remodeling programs that limit lymphocyte trafficking. 展开更多
关键词 immune microenvironment advanced malignant tumorsyet tumor immunotherapy immune cell phenotypic plasticity COLLAGEN tumor stroma collagen I solid tumors
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Differential plasticity of excitatory and inhibitory reticulospinal fibers after spinal cord injury:Implication for recovery
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作者 Rozaria Jeleva Carmen Denecke Muhr +1 位作者 Alina P.Liebisch Florence M.Bareyre 《Neural Regeneration Research》 2026年第5期2011-2020,共10页
The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory ... The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory fibers.While the reticulospinal tract has been shown to be particularly prone to axonal growth and plasticity following injuries of the spinal cord,the differential capacities of excitatory and inhibitory fibers for plasticity remain unclear.As adaptive axonal plasticity involves a sophisticated interplay between excitatory and inhibitory input,we investigated in this study the plastic potential of glutamatergic(vGlut2)and GABAergic(vGat)fibers originating from the gigantocellular nucleus and the lateral paragigantocellular nucleus,two nuclei important for locomotor function.Using a combination of viral tracing,chemogenetic silencing,and AI-based kinematic analysis,we investigated plasticity and its impact on functional recovery within the first 3 weeks following injury,a period prone to neuronal remodeling.We demonstrate that,in this time frame,while vGlut2-positive fibers within the gigantocellular and lateral paragigantocellular nuclei rewire significantly following cervical spinal cord injury,vGat-positive fibers are rather unresponsive to injury.We also show that the acute silencing of excitatory axonal fibers which rewire in response to lesions of the spinal cord triggers a worsening of the functional recovery.Using kinematic analysis,we also pinpoint the locomotion features associated with the gigantocellular nucleus or lateral paragigantocellular nucleus during functional recovery.Overall,our study increases the understanding of the role of the gigantocellular and lateral paragigantocellular nuclei during functional recovery following spinal cord injury. 展开更多
关键词 GABAergic(vGat)fibers gait features glutamatergic(vGlut2)fibers PLASTICITY recovery of function reticulospinal tract spinal cord injury
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两相流条件下微纳塑料颗粒迁移及滞留机理研究
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作者 刘启明 杨志兵 吴婷 《地学前缘》 北大核心 2026年第1期222-235,共14页
微纳塑料(micro/nano-plastics,M/NPs)在多孔介质中的迁移与滞留机制是土壤与地下水污染领域的重要问题,然而受当前可视化技术的限制,两相流条件下M/NPs迁移与滞留过程的细观机理尚不明确。本研究基于三维可视化实验平台,直接观测并量... 微纳塑料(micro/nano-plastics,M/NPs)在多孔介质中的迁移与滞留机制是土壤与地下水污染领域的重要问题,然而受当前可视化技术的限制,两相流条件下M/NPs迁移与滞留过程的细观机理尚不明确。本研究基于三维可视化实验平台,直接观测并量化了渗吸条件下M/NPs在孔隙空间中的分布特征,重点分析了驱替结束后其在多孔介质骨架颗粒接触区、固相表面及液液界面的滞留规律,探究了M/NPs粒径与驱替流量对其空间分布的控制机制。结果表明:M/NPs粒径通过改变M/NPs-固相表面与M/NPs-流体界面间的相互作用能来主导其滞留位点的选择;而M/NPs间的相互作用能大小是决定其能否聚集成团簇并滞留在孔隙空间的关键因素;驱替流量则通过改变固相湿润相界面面积影响其滞留总量。此外,M/NPs滞留在多孔介质中不同点位的主导机制不同,其在多孔介质骨架颗粒接触区的滞留主要受筛分作用控制,而在固相表面与液液界面处的滞留则主要依赖于界面吸附作用。在高剪切条件下滞留在固相表面的M/NPs可能会脱落,而骨架颗粒接触区作为低速区,其聚集团簇数量随流速增大而增加。本研究揭示并量化了M/NPs粒径与流速对其迁移滞留的作用机制,可为预测土壤和地下水等多相流体环境中污染物的迁移与归宿提供重要的理论依据。 展开更多
关键词 微纳塑料 多孔介质 两相流 滞留机理 分布特性
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废塑料回收与催化剂循环利用的耦合路径展望
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作者 潘琼 张晓华 +1 位作者 邢定峰 吕清龙 《石油炼制与化工》 北大核心 2026年第1期159-163,共5页
在“双碳”目标和经济增长背景下,石油化工行业对资源高效利用与绿色循环需求日益迫切。催化剂作为核心单元,其高效使用与循环再生可降低成本、助力碳减排。但传统催化剂再生能耗高、碳排放量大,需寻求低碳高效路径。我国塑料垃圾超过60... 在“双碳”目标和经济增长背景下,石油化工行业对资源高效利用与绿色循环需求日益迫切。催化剂作为核心单元,其高效使用与循环再生可降低成本、助力碳减排。但传统催化剂再生能耗高、碳排放量大,需寻求低碳高效路径。我国塑料垃圾超过60 Mt/a,回收率约为30%,焚烧填埋导致资源浪费和污染。废塑料热解技术能将难回收的塑料转化为液体燃料、可燃气体和炭,促进资源再利用。随着催化剂性能和工艺优化,热解效率提升,热解成为废塑料化学回收重要技术,但由于存在能耗高、受杂质影响及废气残渣难处理等问题,其产业化受到限制。将废塑料热解产物与催化剂循环利用进行耦合,探讨热解气、炭、油在催化剂再生、载体制备及催化裂化中的应用与协同机制,提出集成化低碳方案,可为石化行业绿色转型提供理论与实践支持。 展开更多
关键词 废塑料回收 热解 催化剂再生 循环利用
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隧洞开挖塑性区演化特性参数化表征与代理模型预测
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作者 夏超杰 李鸿鹄 +3 位作者 孙爱军 陈在铁 查新元 徐磊 《水力发电》 2026年第1期52-58,共7页
针对采用传统数值仿真方法获取隧洞开挖过程中围岩塑性区演化特性效率较低的问题,提出了一种隧洞开挖塑性区演化特性曲线快速预测方法。该方法聚焦隧洞横剖面内围岩塑性区面积(深度)随开挖面推进的演化过程这一关键特性,提出采用三参数... 针对采用传统数值仿真方法获取隧洞开挖过程中围岩塑性区演化特性效率较低的问题,提出了一种隧洞开挖塑性区演化特性曲线快速预测方法。该方法聚焦隧洞横剖面内围岩塑性区面积(深度)随开挖面推进的演化过程这一关键特性,提出采用三参数指数型函数对隧洞开挖塑性区演化特性曲线进行参数化表征,并通过构建分别以塑性区演化特性曲线的主要影响因素和表征参数为输入和输出的Kriging代理模型,实现塑性区演化特性曲线的快速预测。以某输水隧洞工程为例,开展了3个典型洞段开挖塑性区演化特性曲线预测,通过与传统数值仿真方法结果的对比,验证了所提方法的可行性与预测精度。 展开更多
关键词 水工隧洞 塑性区演化 快速预测 参数化表征 代理模型
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Effect of Compounding of Sodium Tripolyphosphate and Super Plasticizers on the Hydration of α-calcium Sulfate Hemihydrate 被引量:5
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作者 潘伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期737-744,共8页
The inhibition and its mechanism of sodium tripolyphosphate (STP) composited with super plasticizers (SPs) on hydration of α-calcium sulfate hemihydrate were studied by setting time, strength, hydration heat, X-r... The inhibition and its mechanism of sodium tripolyphosphate (STP) composited with super plasticizers (SPs) on hydration of α-calcium sulfate hemihydrate were studied by setting time, strength, hydration heat, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electronic probe micro analysis (EPMA), scanning electron microscopy (SEM) and differential scanning calorimeter (DSC) measurements. The experimental results show that compared with STP addition, compositing STP with polycarboxylate (PC) plasticizer, the final setting time is prolonged from 0.5h to 2hs. While formulating STP with naphthalene-based plasticizer (NAP) or sulfonate melamine formaldehyde plasticizer (SMF), the final setting time is reduced to quarter of an hour. Similar changes can also be found in the rate of exothermic hydration and hydration degree. Formulating STP with suitable addition of PC can enhance the strength, while compositing STP and NAP or SMF weakens the strength. Besides, adding STP or STP and SMF, obvious movement (more than 1ev) of binding energy of Ca2p1/2 and Ca2p3/2 is detected. Compared with STP addition, content of the characteristic element (P) of STP is cut down form 1.1% to 0.49% by compositing STP with SMF. Furthermore, as hydration age increases, hydration inhibition in the presence of admixtures weakens and even disappears within 56 h. 展开更多
关键词 α-calcium sulfate hemihydrate HYDRATION sodium tripolyphosphate plasticizer ADSORPTION
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Surface sulfur vacancies enhanced electron transfer over Co-ZnS quantum dots for efficient degradation of plasticizer micropollutants by peroxymonosulfate activation 被引量:5
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作者 Yuting Gu Tingting Gao +5 位作者 Fagen Zhang Chao Lu Wenrui Cao Ziwei Fu Chun Hu Lai Lyu 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第8期3829-3834,共6页
Peroxymonosulfate(PMS)activation in heterogeneous processes is a promising water treatment technology.Nevertheless,the high energy consumption and low efficiency during the reaction are ineluctable,due to electron cyc... Peroxymonosulfate(PMS)activation in heterogeneous processes is a promising water treatment technology.Nevertheless,the high energy consumption and low efficiency during the reaction are ineluctable,due to electron cycling rate limitation.Herein,a new strategy is proposed based on a quantum dots(QDs)/PMS system.Co-ZnS QDs are synthesized by a water phase coprecipitation method.The inequivalent lattice-doping of Co for Zn leads to the generation of surface sulfur vacancies(SVs),which modulates the surface of the catalyst to form an electronic nonequilibrium surface.Astonishingly,the plasticizer micropollutants can be completely degraded within only tens of seconds in the Co-Zn S QDs/PMS system due to this type of surface modulation.The interfacial reaction mechanism is revealed that pollutants tend to be adsorbed on the cobalt metal sites as the electron donors,where the internal electrons of pollutants are captured by the metal species and transferred to the surface SVs.Meanwhile,PMS adsorbed on the SVs is reduced to radicals by capturing electrons,achieving effective electron recovery.Dissolved oxygen(DO)molecules are also easily attracted to catalyst defects and are reduced to O_(2)^(·-),further promoting the degradation of pollutants. 展开更多
关键词 Peroxymonosulfate activation Sulfur vacancy Quantum dots ZNS plasticizer
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Understanding the alkyl effect of geminal dinitropropyl ester energetic plasticizers on hydroxyl terminated polybutadiene(HTPB):Simultaneous tuning on low temperature behavior and processability 被引量:4
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作者 Baodong Zhao Yinglei Wang +3 位作者 Fulei Gao Yajing Liu Weixiao Liu Feng Ding 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期364-371,共8页
Geminal dinitropropyl ester plasticizers(DNPEPs) possess excellent energetic performances which provide good potentials as insensitive plasticizer. In this study, we design and synthesize DNPEPs with different alkane ... Geminal dinitropropyl ester plasticizers(DNPEPs) possess excellent energetic performances which provide good potentials as insensitive plasticizer. In this study, we design and synthesize DNPEPs with different alkane chain parts, and systematically investigate their structure-property relationships.Results show that DNPEPs have impact sensitivities all higher than 25.2 J, thermal decomposition temperatures all higher than 254 ℃, and glass transition temperatures(T_(g)) lower than-90 ℃.Furthermore, the effects of DNPEPs as plasticizer are studied on hydroxyl terminated polybutadiene(HTPB) in detail, including the viscosity, glass transition temperatures and others. It is noteworthy that 2,2-dinitropropyl nonanoate(DNPNc) among these DNPEPs exhibits the most expected simultaneous tuning effects on both viscosity and T_(g) of HTPB systems, providing favorable potentials to replace the conventional plastizers as dioctyl sebacate(DOS) in the HTPB based propellants and explosives. 展开更多
关键词 Molecular simulation Experimental validation Preparation Energetic plasticizer Glass transition temperature Viscosity
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有氧和抗阻运动改善肥胖相关认知障碍的作用机制
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作者 刘煜 雷森林 +2 位作者 周锦涛 刘辉 李先辉 《中国组织工程研究》 北大核心 2026年第5期1171-1183,共13页
背景:肥胖不仅与糖尿病、心血管疾病等代谢性疾病有关,还与认知功能下降、痴呆等神经退行性疾病的风险增加密切相关。研究发现,有氧运动和抗阻运动有助于改善肥胖相关认知障碍,然而治疗效果和相关作用机制尚不明确。目的:探究有氧运动... 背景:肥胖不仅与糖尿病、心血管疾病等代谢性疾病有关,还与认知功能下降、痴呆等神经退行性疾病的风险增加密切相关。研究发现,有氧运动和抗阻运动有助于改善肥胖相关认知障碍,然而治疗效果和相关作用机制尚不明确。目的:探究有氧运动、抗阻运动对肥胖相关认知障碍小鼠神经中枢的保护作用及机制。方法:48只8周龄C57BL/6J野生型雄性小鼠随机分为4组:对照组正常饲养20周;高脂组用高脂饲料(60%脂肪供能)饲养20周;有氧运动组高脂饲养12周后,有氧运动干预8周;抗阻运动组高脂饲养12周后,抗阻运动干预8周。运动干预结束后分别称量体质量,进行胰岛素耐量测试、葡萄糖耐量测试、新物体识别实验和Y迷宫实验;苏木精-伊红染色观察各组小鼠海马和皮质组织细胞形态;实时荧光定量PCR检测肿瘤坏死因子α和白细胞介素6 mRNA表达;Western blot检测Bax、Bcl-2、核因子κB、Cleaved Caspase-1、Caspase-3、突触蛋白1、脑源性神经营养因子蛋白表达。结果与结论:①与对照组相比,高脂组小鼠体质量增加(P<0.05),并伴随胰岛素抵抗以及认知功能障碍发生,海马组织中核因子κB、Bax、Caspase-3、Cleaved Caspase-1蛋白表达显著增加(P<0.05),脑源性神经营养因子、突触蛋白1、Bcl-2蛋白表达显著降低(P<0.05),Bcl-2/Bax比值显著降低(P<0.05),炎症因子肿瘤坏死因子α和白细胞介素6 mRNA表达显著增加(P<0.05)。②与高脂组相比,有氧运动组小鼠上述指标均得到显著改善(P<0.05),而抗阻运动组小鼠体质量减轻、炎症因子肿瘤坏死因子α、白细胞介素6 mRNA表达显著降低(P<0.05)、Caspase-3蛋白表达显著降低(P<0.05)以及脑源性神经营养因子蛋白表达显著增加(P<0.05),其他指标无显著变化(P>0.05)。综合以上结果发现,长期运动可通过降低肥胖小鼠胰岛素抵抗、下调核因子κB通路表达、减轻炎症反应、抑制神经元凋亡和改善突触可塑性产生神经保护作用,有效缓解肥胖相关认知功能障碍,其中有氧运动的治疗效果优于抗阻运动。 展开更多
关键词 肥胖相关认知障碍 核因子ΚB 有氧运动 抗阻运动 神经炎症 突触可塑性 凋亡 工程化组织构建
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